Package org.eclipse.sisu.space.asm

Class MethodWriter

  • final class MethodWriter
extends MethodVisitor
    A MethodVisitor that generates methods in bytecode form. Each visit method of this class appends the bytecode corresponding to the visited instruction to a byte vector, in the order these methods are called.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      (package private) static int ACC_CONSTRUCTOR
      Pseudo access flag used to denote constructors.
      private int access
      Access flags of this method.
      private ByteVector annd
      The annotation default attribute of this method.
      private AnnotationWriter anns
      The runtime visible annotations of this method.
      (package private) static int APPEND_FRAME
      Frame where current locals are the same as the locals in the previous frame, except that k additional locals are defined.
      private Attribute attrs
      The non standard attributes of the method.
      private Attribute cattrs
      The non standard attributes of the method's code.
      (package private) static int CHOP_FRAME
      Frame where current locals are the same as the locals in the previous frame, except that the k last locals are absent.
      (package private) int classReaderLength
      If not zero, indicates that the code of this method must be copied from the ClassReader associated to this writer in cw.cr.
      (package private) int classReaderOffset
      If not zero, indicates that the code of this method must be copied from the ClassReader associated to this writer in cw.cr.
      private ByteVector code
      The bytecode of this method.
      private int compute
      Indicates what must be automatically computed.
      private AnnotationWriter ctanns
      The runtime visible type annotations of the code.
      private Label currentBlock
      The current basic block.
      private int currentLocals
      Number of local variables in the current stack map frame.
      (package private) ClassWriter cw
      The class writer to which this method must be added.
      private int desc
      The index of the constant pool item that contains the descriptor of this method.
      private java.lang.String descriptor
      The descriptor of this method.
      (package private) int exceptionCount
      Number of exceptions that can be thrown by this method.
      (package private) int[] exceptions
      The exceptions that can be thrown by this method.
      private Handler firstHandler
      The first element in the exception handler list.
      private int[] frame
      The current stack map frame.
      private int frameCount
      Number of stack map frames in the StackMapTable attribute.
      private static int FRAMES
      Indicates that the stack map frames must be recomputed from scratch.
      (package private) static int FULL_FRAME
      Full frame
      private int handlerCount
      Number of elements in the exception handler list.
      private AnnotationWriter ianns
      The runtime invisible annotations of this method.
      private AnnotationWriter ictanns
      The runtime invisible type annotations of the code.
      private AnnotationWriter[] ipanns
      The runtime invisible parameter annotations of this method.
      private AnnotationWriter itanns
      The runtime invisible type annotations of this method.
      private Label labels
      A list of labels.
      private int lastCodeOffset
      The start offset of the last visited instruction.
      private Handler lastHandler
      The last element in the exception handler list.
      private ByteVector lineNumber
      The LineNumberTable attribute.
      private int lineNumberCount
      Number of entries in the LineNumberTable attribute.
      private ByteVector localVar
      The LocalVariableTable attribute.
      private int localVarCount
      Number of entries in the LocalVariableTable attribute.
      private ByteVector localVarType
      The LocalVariableTypeTable attribute.
      private int localVarTypeCount
      Number of entries in the LocalVariableTypeTable attribute.
      private int maxLocals
      Maximum number of local variables for this method.
      private static int MAXS
      Indicates that the maximum stack size and number of local variables must be automatically computed.
      private int maxStack
      Maximum stack size of this method.
      private int maxStackSize
      The (relative) maximum stack size after the last visited instruction.
      private ByteVector methodParameters
      The MethodParameters attribute.
      private int methodParametersCount
      Number of entries in the MethodParameters attribute.
      private int name
      The index of the constant pool item that contains the name of this method.
      private static int NOTHING
      Indicates that nothing must be automatically computed.
      private AnnotationWriter[] panns
      The runtime visible parameter annotations of this method.
      private Label previousBlock
      The previous basic block.
      private int[] previousFrame
      The last frame that was written in the StackMapTable attribute.
      private int previousFrameOffset
      The offset of the last frame that was written in the StackMapTable attribute.
      (package private) static int RESERVED
      Reserved for future use
      private boolean resize
      Indicates if some jump instructions are too small and need to be resized.
      (package private) static int SAME_FRAME
      Frame has exactly the same locals as the previous stack map frame and number of stack items is zero.
      (package private) static int SAME_FRAME_EXTENDED
      Frame has exactly the same locals as the previous stack map frame and number of stack items is zero.
      (package private) static int SAME_LOCALS_1_STACK_ITEM_FRAME
      Frame has exactly the same locals as the previous stack map frame and number of stack items is 1
      (package private) static int SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED
      Frame has exactly the same locals as the previous stack map frame and number of stack items is 1.
      (package private) java.lang.String signature
      The signature of this method.
      private ByteVector stackMap
      The StackMapTable attribute.
      private int stackSize
      The (relative) stack size after the last visited instruction.
      private int subroutines
      The number of subroutines in this method.
      private int synthetics
      The number of synthetic parameters of this method.
      private AnnotationWriter tanns
      The runtime visible type annotations of this method.

    • Constructor Summary

      Constructors 
      Constructor Description
      MethodWriter​(ClassWriter cw, int access, java.lang.String name, java.lang.String desc, java.lang.String signature, java.lang.String[] exceptions, boolean computeMaxs, boolean computeFrames)
      Constructs a new MethodWriter.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      private void addSuccessor​(int info, Label successor)
      Adds a successor to the currentBlock block.
      private void endFrame()
      Checks if the visit of the current frame frame is finished, and if yes, write it in the StackMapTable attribute.
      (package private) static int getNewOffset​(int[] indexes, int[] sizes, int begin, int end)
      Computes the future value of a bytecode offset.
      (package private) static void getNewOffset​(int[] indexes, int[] sizes, Label label)
      Updates the offset of the given label.
      (package private) int getSize()
      Returns the size of the bytecode of this method.
      private void noSuccessor()
      Ends the current basic block.
      (package private) void put​(ByteVector out)
      Puts the bytecode of this method in the given byte vector.
      (package private) static int readInt​(byte[] b, int index)
      Reads a signed int value in the given byte array.
      (package private) static short readShort​(byte[] b, int index)
      Reads a signed short value in the given byte array.
      (package private) static int readUnsignedShort​(byte[] b, int index)
      Reads an unsigned short value in the given byte array.
      private void resizeInstructions()
      Resizes and replaces the temporary instructions inserted by Label.resolve(org.eclipse.sisu.space.asm.MethodWriter, int, byte[]) for wide forward jumps, while keeping jump offsets and instruction addresses consistent.
      private int startFrame​(int offset, int nLocal, int nStack)
      Starts the visit of a stack map frame.
      AnnotationVisitor visitAnnotation​(java.lang.String desc, boolean visible)
      Visits an annotation of this method.
      AnnotationVisitor visitAnnotationDefault()
      Visits the default value of this annotation interface method.
      void visitAttribute​(Attribute attr)
      Visits a non standard attribute of this method.
      void visitCode()
      Starts the visit of the method's code, if any (i.e.
      void visitEnd()
      Visits the end of the method.
      void visitFieldInsn​(int opcode, java.lang.String owner, java.lang.String name, java.lang.String desc)
      Visits a field instruction.
      void visitFrame​(int type, int nLocal, java.lang.Object[] local, int nStack, java.lang.Object[] stack)
      Visits the current state of the local variables and operand stack elements.
      private void visitFrame​(Frame f)
      Visits a frame that has been computed from scratch.
      void visitIincInsn​(int var, int increment)
      Visits an IINC instruction.
      private void visitImplicitFirstFrame()
      Visit the implicit first frame of this method.
      void visitInsn​(int opcode)
      Visits a zero operand instruction.
      AnnotationVisitor visitInsnAnnotation​(int typeRef, TypePath typePath, java.lang.String desc, boolean visible)
      Visits an annotation on an instruction.
      void visitIntInsn​(int opcode, int operand)
      Visits an instruction with a single int operand.
      void visitInvokeDynamicInsn​(java.lang.String name, java.lang.String desc, Handle bsm, java.lang.Object... bsmArgs)
      Visits an invokedynamic instruction.
      void visitJumpInsn​(int opcode, Label label)
      Visits a jump instruction.
      void visitLabel​(Label label)
      Visits a label.
      void visitLdcInsn​(java.lang.Object cst)
      Visits a LDC instruction.
      void visitLineNumber​(int line, Label start)
      Visits a line number declaration.
      void visitLocalVariable​(java.lang.String name, java.lang.String desc, java.lang.String signature, Label start, Label end, int index)
      Visits a local variable declaration.
      AnnotationVisitor visitLocalVariableAnnotation​(int typeRef, TypePath typePath, Label[] start, Label[] end, int[] index, java.lang.String desc, boolean visible)
      Visits an annotation on a local variable type.
      void visitLookupSwitchInsn​(Label dflt, int[] keys, Label[] labels)
      Visits a LOOKUPSWITCH instruction.
      void visitMaxs​(int maxStack, int maxLocals)
      Visits the maximum stack size and the maximum number of local variables of the method.
      void visitMethodInsn​(int opcode, java.lang.String owner, java.lang.String name, java.lang.String desc, boolean itf)
      Visits a method instruction.
      void visitMultiANewArrayInsn​(java.lang.String desc, int dims)
      Visits a MULTIANEWARRAY instruction.
      void visitParameter​(java.lang.String name, int access)
      Visits a parameter of this method.
      AnnotationVisitor visitParameterAnnotation​(int parameter, java.lang.String desc, boolean visible)
      Visits an annotation of a parameter this method.
      private void visitSwitchInsn​(Label dflt, Label[] labels)  
      void visitTableSwitchInsn​(int min, int max, Label dflt, Label... labels)
      Visits a TABLESWITCH instruction.
      AnnotationVisitor visitTryCatchAnnotation​(int typeRef, TypePath typePath, java.lang.String desc, boolean visible)
      Visits an annotation on an exception handler type.
      void visitTryCatchBlock​(Label start, Label end, Label handler, java.lang.String type)
      Visits a try catch block.
      AnnotationVisitor visitTypeAnnotation​(int typeRef, TypePath typePath, java.lang.String desc, boolean visible)
      Visits an annotation on a type in the method signature.
      void visitTypeInsn​(int opcode, java.lang.String type)
      Visits a type instruction.
      void visitVarInsn​(int opcode, int var)
      Visits a local variable instruction.
      private void writeFrame()
      Compress and writes the current frame frame in the StackMapTable attribute.
      private void writeFrameType​(java.lang.Object type)  
      private void writeFrameTypes​(int start, int end)
      Writes some types of the current frame frame into the StackMapTableAttribute.
      (package private) static void writeShort​(byte[] b, int index, int s)
      Writes a short value in the given byte array.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • ACC_CONSTRUCTOR

        static final int ACC_CONSTRUCTOR
        Pseudo access flag used to denote constructors.
        See Also:
        Constant Field Values

      • SAME_FRAME

        static final int SAME_FRAME
        Frame has exactly the same locals as the previous stack map frame and number of stack items is zero.
        See Also:
        Constant Field Values

      • SAME_LOCALS_1_STACK_ITEM_FRAME

        static final int SAME_LOCALS_1_STACK_ITEM_FRAME
        Frame has exactly the same locals as the previous stack map frame and number of stack items is 1
        See Also:
        Constant Field Values

      • SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED

        static final int SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED
        Frame has exactly the same locals as the previous stack map frame and number of stack items is 1. Offset is bigger then 63;
        See Also:
        Constant Field Values

      • CHOP_FRAME

        static final int CHOP_FRAME
        Frame where current locals are the same as the locals in the previous frame, except that the k last locals are absent. The value of k is given by the formula 251-frame_type.
        See Also:
        Constant Field Values

      • SAME_FRAME_EXTENDED

        static final int SAME_FRAME_EXTENDED
        Frame has exactly the same locals as the previous stack map frame and number of stack items is zero. Offset is bigger then 63;
        See Also:
        Constant Field Values

      • APPEND_FRAME

        static final int APPEND_FRAME
        Frame where current locals are the same as the locals in the previous frame, except that k additional locals are defined. The value of k is given by the formula frame_type-251.
        See Also:
        Constant Field Values

      • FRAMES

        private static final int FRAMES
        Indicates that the stack map frames must be recomputed from scratch. In this case the maximum stack size and number of local variables is also recomputed from scratch.
        See Also:
        compute, Constant Field Values

      • MAXS

        private static final int MAXS
        Indicates that the maximum stack size and number of local variables must be automatically computed.
        See Also:
        compute, Constant Field Values

      • cw

        final ClassWriter cw
        The class writer to which this method must be added.

      • access

        private int access
        Access flags of this method.

      • name

        private final int name
        The index of the constant pool item that contains the name of this method.

      • desc

        private final int desc
        The index of the constant pool item that contains the descriptor of this method.

      • descriptor

        private final java.lang.String descriptor
        The descriptor of this method.

      • signature

        java.lang.String signature
        The signature of this method.

      • classReaderOffset

        int classReaderOffset
        If not zero, indicates that the code of this method must be copied from the ClassReader associated to this writer in cw.cr. More precisely, this field gives the index of the first byte to copied from cw.cr.b.

      • classReaderLength

        int classReaderLength
        If not zero, indicates that the code of this method must be copied from the ClassReader associated to this writer in cw.cr. More precisely, this field gives the number of bytes to copied from cw.cr.b.

      • exceptionCount

        int exceptionCount
        Number of exceptions that can be thrown by this method.

      • exceptions

        int[] exceptions
        The exceptions that can be thrown by this method. More precisely, this array contains the indexes of the constant pool items that contain the internal names of these exception classes.

      • annd

        private ByteVector annd
        The annotation default attribute of this method. May be null.

      • anns

        private AnnotationWriter anns
        The runtime visible annotations of this method. May be null.

      • ianns

        private AnnotationWriter ianns
        The runtime invisible annotations of this method. May be null.

      • tanns

        private AnnotationWriter tanns
        The runtime visible type annotations of this method. May be null .

      • itanns

        private AnnotationWriter itanns
        The runtime invisible type annotations of this method. May be null.

      • panns

        private AnnotationWriter[] panns
        The runtime visible parameter annotations of this method. May be null.

      • ipanns

        private AnnotationWriter[] ipanns
        The runtime invisible parameter annotations of this method. May be null.

      • synthetics

        private int synthetics
        The number of synthetic parameters of this method.

      • attrs

        private Attribute attrs
        The non standard attributes of the method.

      • code

        private ByteVector code
        The bytecode of this method.

      • maxStack

        private int maxStack
        Maximum stack size of this method.

      • maxLocals

        private int maxLocals
        Maximum number of local variables for this method.

      • currentLocals

        private int currentLocals
        Number of local variables in the current stack map frame.

      • frameCount

        private int frameCount
        Number of stack map frames in the StackMapTable attribute.

      • stackMap

        private ByteVector stackMap
        The StackMapTable attribute.

      • previousFrameOffset

        private int previousFrameOffset
        The offset of the last frame that was written in the StackMapTable attribute.

      • previousFrame

        private int[] previousFrame
        The last frame that was written in the StackMapTable attribute.
        See Also:
        frame

      • frame

        private int[] frame
        The current stack map frame. The first element contains the offset of the instruction to which the frame corresponds, the second element is the number of locals and the third one is the number of stack elements. The local variables start at index 3 and are followed by the operand stack values. In summary frame[0] = offset, frame[1] = nLocal, frame[2] = nStack, frame[3] = nLocal. All types are encoded as integers, with the same format as the one used in Label, but limited to BASE types.

      • handlerCount

        private int handlerCount
        Number of elements in the exception handler list.

      • firstHandler

        private Handler firstHandler
        The first element in the exception handler list.

      • lastHandler

        private Handler lastHandler
        The last element in the exception handler list.

      • methodParametersCount

        private int methodParametersCount
        Number of entries in the MethodParameters attribute.

      • methodParameters

        private ByteVector methodParameters
        The MethodParameters attribute.

      • localVarCount

        private int localVarCount
        Number of entries in the LocalVariableTable attribute.

      • localVar

        private ByteVector localVar
        The LocalVariableTable attribute.

      • localVarTypeCount

        private int localVarTypeCount
        Number of entries in the LocalVariableTypeTable attribute.

      • localVarType

        private ByteVector localVarType
        The LocalVariableTypeTable attribute.

      • lineNumberCount

        private int lineNumberCount
        Number of entries in the LineNumberTable attribute.

      • lineNumber

        private ByteVector lineNumber
        The LineNumberTable attribute.

      • lastCodeOffset

        private int lastCodeOffset
        The start offset of the last visited instruction.

      • ctanns

        private AnnotationWriter ctanns
        The runtime visible type annotations of the code. May be null.

      • ictanns

        private AnnotationWriter ictanns
        The runtime invisible type annotations of the code. May be null.

      • cattrs

        private Attribute cattrs
        The non standard attributes of the method's code.

      • resize

        private boolean resize
        Indicates if some jump instructions are too small and need to be resized.

      • subroutines

        private int subroutines
        The number of subroutines in this method.

      • compute

        private final int compute
        Indicates what must be automatically computed.
        See Also:
        FRAMES, MAXS, NOTHING

      • previousBlock

        private Label previousBlock
        The previous basic block.

      • currentBlock

        private Label currentBlock
        The current basic block.

      • stackSize

        private int stackSize
        The (relative) stack size after the last visited instruction. This size is relative to the beginning of the current basic block, i.e., the true stack size after the last visited instruction is equal to the beginStackSize of the current basic block plus stackSize.

      • maxStackSize

        private int maxStackSize
        The (relative) maximum stack size after the last visited instruction. This size is relative to the beginning of the current basic block, i.e., the true maximum stack size after the last visited instruction is equal to the beginStackSize of the current basic block plus stackSize.

    • Constructor Detail

      • MethodWriter

        MethodWriter​(ClassWriter cw,
             int access,
             java.lang.String name,
             java.lang.String desc,
             java.lang.String signature,
             java.lang.String[] exceptions,
             boolean computeMaxs,
             boolean computeFrames)
        Constructs a new MethodWriter.
        Parameters:
        cw - the class writer in which the method must be added.
        access - the method's access flags (see Opcodes).
        name - the method's name.
        desc - the method's descriptor (see Type).
        signature - the method's signature. May be null.
        exceptions - the internal names of the method's exceptions. May be null.
        computeMaxs - true if the maximum stack size and number of local variables must be automatically computed.
        computeFrames - true if the stack map tables must be recomputed from scratch.

    • Method Detail

      • visitParameter

        public void visitParameter​(java.lang.String name,
                           int access)
        Description copied from class: MethodVisitor
        Visits a parameter of this method.
        Overrides:
        visitParameter in class MethodVisitor
        Parameters:
        name - parameter name or null if none is provided.
        access - the parameter's access flags, only ACC_FINAL, ACC_SYNTHETIC or/and ACC_MANDATED are allowed (see Opcodes).

      • visitAnnotationDefault

        public AnnotationVisitor visitAnnotationDefault()
        Description copied from class: MethodVisitor
        Visits the default value of this annotation interface method.
        Overrides:
        visitAnnotationDefault in class MethodVisitor
        Returns:
        a visitor to the visit the actual default value of this annotation interface method, or null if this visitor is not interested in visiting this default value. The 'name' parameters passed to the methods of this annotation visitor are ignored. Moreover, exacly one visit method must be called on this annotation visitor, followed by visitEnd.

      • visitAnnotation

        public AnnotationVisitor visitAnnotation​(java.lang.String desc,
                                         boolean visible)
        Description copied from class: MethodVisitor
        Visits an annotation of this method.
        Overrides:
        visitAnnotation in class MethodVisitor
        Parameters:
        desc - the class descriptor of the annotation class.
        visible - true if the annotation is visible at runtime.
        Returns:
        a visitor to visit the annotation values, or null if this visitor is not interested in visiting this annotation.

      • visitTypeAnnotation

        public AnnotationVisitor visitTypeAnnotation​(int typeRef,
                                             TypePath typePath,
                                             java.lang.String desc,
                                             boolean visible)
        Description copied from class: MethodVisitor
        Visits an annotation on a type in the method signature.
        Overrides:
        visitTypeAnnotation in class MethodVisitor
        Parameters:
        typeRef - a reference to the annotated type. The sort of this type reference must be METHOD_TYPE_PARAMETER, METHOD_TYPE_PARAMETER_BOUND, METHOD_RETURN, METHOD_RECEIVER, METHOD_FORMAL_PARAMETER or THROWS. See TypeReference.
        typePath - the path to the annotated type argument, wildcard bound, array element type, or static inner type within 'typeRef'. May be null if the annotation targets 'typeRef' as a whole.
        desc - the class descriptor of the annotation class.
        visible - true if the annotation is visible at runtime.
        Returns:
        a visitor to visit the annotation values, or null if this visitor is not interested in visiting this annotation.

      • visitParameterAnnotation

        public AnnotationVisitor visitParameterAnnotation​(int parameter,
                                                  java.lang.String desc,
                                                  boolean visible)
        Description copied from class: MethodVisitor
        Visits an annotation of a parameter this method.
        Overrides:
        visitParameterAnnotation in class MethodVisitor
        Parameters:
        parameter - the parameter index.
        desc - the class descriptor of the annotation class.
        visible - true if the annotation is visible at runtime.
        Returns:
        a visitor to visit the annotation values, or null if this visitor is not interested in visiting this annotation.

      • visitCode

        public void visitCode()
        Description copied from class: MethodVisitor
        Starts the visit of the method's code, if any (i.e. non abstract method).
        Overrides:
        visitCode in class MethodVisitor

      • visitFrame

        public void visitFrame​(int type,
                       int nLocal,
                       java.lang.Object[] local,
                       int nStack,
                       java.lang.Object[] stack)
        Description copied from class: MethodVisitor
        Visits the current state of the local variables and operand stack elements. This method must(*) be called just before any instruction i that follows an unconditional branch instruction such as GOTO or THROW, that is the target of a jump instruction, or that starts an exception handler block. The visited types must describe the values of the local variables and of the operand stack elements just before i is executed.

        (*) this is mandatory only for classes whose version is greater than or equal to V1_6.

        The frames of a method must be given either in expanded form, or in compressed form (all frames must use the same format, i.e. you must not mix expanded and compressed frames within a single method):
        • In expanded form, all frames must have the F_NEW type.
        • In compressed form, frames are basically "deltas" from the state of the previous frame:
          • Opcodes.F_SAME representing frame with exactly the same locals as the previous frame and with the empty stack.
          • Opcodes.F_SAME1 representing frame with exactly the same locals as the previous frame and with single value on the stack ( nStack is 1 and stack[0] contains value for the type of the stack item).
          • Opcodes.F_APPEND representing frame with current locals are the same as the locals in the previous frame, except that additional locals are defined (nLocal is 1, 2 or 3 and local elements contains values representing added types).
          • Opcodes.F_CHOP representing frame with current locals are the same as the locals in the previous frame, except that the last 1-3 locals are absent and with the empty stack (nLocals is 1, 2 or 3).
          • Opcodes.F_FULL representing complete frame data.

        In both cases the first frame, corresponding to the method's parameters and access flags, is implicit and must not be visited. Also, it is illegal to visit two or more frames for the same code location (i.e., at least one instruction must be visited between two calls to visitFrame).
        Overrides:
        visitFrame in class MethodVisitor
        Parameters:
        type - the type of this stack map frame. Must be Opcodes.F_NEW for expanded frames, or Opcodes.F_FULL, Opcodes.F_APPEND, Opcodes.F_CHOP, Opcodes.F_SAME or Opcodes.F_APPEND, Opcodes.F_SAME1 for compressed frames.
        nLocal - the number of local variables in the visited frame.
        local - the local variable types in this frame. This array must not be modified. Primitive types are represented by Opcodes.TOP, Opcodes.INTEGER, Opcodes.FLOAT, Opcodes.LONG, Opcodes.DOUBLE,Opcodes.NULL or Opcodes.UNINITIALIZED_THIS (long and double are represented by a single element). Reference types are represented by String objects (representing internal names), and uninitialized types by Label objects (this label designates the NEW instruction that created this uninitialized value).
        nStack - the number of operand stack elements in the visited frame.
        stack - the operand stack types in this frame. This array must not be modified. Its content has the same format as the "local" array.

      • visitInsn

        public void visitInsn​(int opcode)
        Description copied from class: MethodVisitor
        Visits a zero operand instruction.
        Overrides:
        visitInsn in class MethodVisitor
        Parameters:
        opcode - the opcode of the instruction to be visited. This opcode is either NOP, ACONST_NULL, ICONST_M1, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4, ICONST_5, LCONST_0, LCONST_1, FCONST_0, FCONST_1, FCONST_2, DCONST_0, DCONST_1, IALOAD, LALOAD, FALOAD, DALOAD, AALOAD, BALOAD, CALOAD, SALOAD, IASTORE, LASTORE, FASTORE, DASTORE, AASTORE, BASTORE, CASTORE, SASTORE, POP, POP2, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, SWAP, IADD, LADD, FADD, DADD, ISUB, LSUB, FSUB, DSUB, IMUL, LMUL, FMUL, DMUL, IDIV, LDIV, FDIV, DDIV, IREM, LREM, FREM, DREM, INEG, LNEG, FNEG, DNEG, ISHL, LSHL, ISHR, LSHR, IUSHR, LUSHR, IAND, LAND, IOR, LOR, IXOR, LXOR, I2L, I2F, I2D, L2I, L2F, L2D, F2I, F2L, F2D, D2I, D2L, D2F, I2B, I2C, I2S, LCMP, FCMPL, FCMPG, DCMPL, DCMPG, IRETURN, LRETURN, FRETURN, DRETURN, ARETURN, RETURN, ARRAYLENGTH, ATHROW, MONITORENTER, or MONITOREXIT.

      • visitVarInsn

        public void visitVarInsn​(int opcode,
                         int var)
        Description copied from class: MethodVisitor
        Visits a local variable instruction. A local variable instruction is an instruction that loads or stores the value of a local variable.
        Overrides:
        visitVarInsn in class MethodVisitor
        Parameters:
        opcode - the opcode of the local variable instruction to be visited. This opcode is either ILOAD, LLOAD, FLOAD, DLOAD, ALOAD, ISTORE, LSTORE, FSTORE, DSTORE, ASTORE or RET.
        var - the operand of the instruction to be visited. This operand is the index of a local variable.

      • visitTypeInsn

        public void visitTypeInsn​(int opcode,
                          java.lang.String type)
        Description copied from class: MethodVisitor
        Visits a type instruction. A type instruction is an instruction that takes the internal name of a class as parameter.
        Overrides:
        visitTypeInsn in class MethodVisitor
        Parameters:
        opcode - the opcode of the type instruction to be visited. This opcode is either NEW, ANEWARRAY, CHECKCAST or INSTANCEOF.
        type - the operand of the instruction to be visited. This operand must be the internal name of an object or array class (see getInternalName).

      • visitFieldInsn

        public void visitFieldInsn​(int opcode,
                           java.lang.String owner,
                           java.lang.String name,
                           java.lang.String desc)
        Description copied from class: MethodVisitor
        Visits a field instruction. A field instruction is an instruction that loads or stores the value of a field of an object.
        Overrides:
        visitFieldInsn in class MethodVisitor
        Parameters:
        opcode - the opcode of the type instruction to be visited. This opcode is either GETSTATIC, PUTSTATIC, GETFIELD or PUTFIELD.
        owner - the internal name of the field's owner class (see getInternalName).
        name - the field's name.
        desc - the field's descriptor (see Type).

      • visitMethodInsn

        public void visitMethodInsn​(int opcode,
                            java.lang.String owner,
                            java.lang.String name,
                            java.lang.String desc,
                            boolean itf)
        Description copied from class: MethodVisitor
        Visits a method instruction. A method instruction is an instruction that invokes a method.
        Overrides:
        visitMethodInsn in class MethodVisitor
        Parameters:
        opcode - the opcode of the type instruction to be visited. This opcode is either INVOKEVIRTUAL, INVOKESPECIAL, INVOKESTATIC or INVOKEINTERFACE.
        owner - the internal name of the method's owner class (see getInternalName).
        name - the method's name.
        desc - the method's descriptor (see Type).
        itf - if the method's owner class is an interface.

      • visitInvokeDynamicInsn

        public void visitInvokeDynamicInsn​(java.lang.String name,
                                   java.lang.String desc,
                                   Handle bsm,
                                   java.lang.Object... bsmArgs)
        Description copied from class: MethodVisitor
        Visits an invokedynamic instruction.
        Overrides:
        visitInvokeDynamicInsn in class MethodVisitor
        Parameters:
        name - the method's name.
        desc - the method's descriptor (see Type).
        bsm - the bootstrap method.
        bsmArgs - the bootstrap method constant arguments. Each argument must be an Integer, Float, Long, Double, String, Type or Handle value. This method is allowed to modify the content of the array so a caller should expect that this array may change.

      • visitJumpInsn

        public void visitJumpInsn​(int opcode,
                          Label label)
        Description copied from class: MethodVisitor
        Visits a jump instruction. A jump instruction is an instruction that may jump to another instruction.
        Overrides:
        visitJumpInsn in class MethodVisitor
        Parameters:
        opcode - the opcode of the type instruction to be visited. This opcode is either IFEQ, IFNE, IFLT, IFGE, IFGT, IFLE, IF_ICMPEQ, IF_ICMPNE, IF_ICMPLT, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ACMPEQ, IF_ACMPNE, GOTO, JSR, IFNULL or IFNONNULL.
        label - the operand of the instruction to be visited. This operand is a label that designates the instruction to which the jump instruction may jump.

      • visitLabel

        public void visitLabel​(Label label)
        Description copied from class: MethodVisitor
        Visits a label. A label designates the instruction that will be visited just after it.
        Overrides:
        visitLabel in class MethodVisitor
        Parameters:
        label - a Label object.

      • visitLdcInsn

        public void visitLdcInsn​(java.lang.Object cst)
        Description copied from class: MethodVisitor
        Visits a LDC instruction. Note that new constant types may be added in future versions of the Java Virtual Machine. To easily detect new constant types, implementations of this method should check for unexpected constant types, like this: 
         if (cst instanceof Integer) {
     // ...
 } else if (cst instanceof Float) {
     // ...
 } else if (cst instanceof Long) {
     // ...
 } else if (cst instanceof Double) {
     // ...
 } else if (cst instanceof String) {
     // ...
 } else if (cst instanceof Type) {
     int sort = ((Type) cst).getSort();
     if (sort == Type.OBJECT) {
         // ...
     } else if (sort == Type.ARRAY) {
         // ...
     } else if (sort == Type.METHOD) {
         // ...
     } else {
         // throw an exception
     }
 } else if (cst instanceof Handle) {
     // ...
 } else {
     // throw an exception
 }
        Overrides:
        visitLdcInsn in class MethodVisitor
        Parameters:
        cst - the constant to be loaded on the stack. This parameter must be a non null Integer, a Float, a Long, a Double, a String, a Type of OBJECT or ARRAY sort for .class constants, for classes whose version is 49.0, a Type of METHOD sort or a Handle for MethodType and MethodHandle constants, for classes whose version is 51.0.

      • visitIincInsn

        public void visitIincInsn​(int var,
                          int increment)
        Description copied from class: MethodVisitor
        Visits an IINC instruction.
        Overrides:
        visitIincInsn in class MethodVisitor
        Parameters:
        var - index of the local variable to be incremented.
        increment - amount to increment the local variable by.

      • visitTableSwitchInsn

        public void visitTableSwitchInsn​(int min,
                                 int max,
                                 Label dflt,
                                 Label... labels)
        Description copied from class: MethodVisitor
        Visits a TABLESWITCH instruction.
        Overrides:
        visitTableSwitchInsn in class MethodVisitor
        Parameters:
        min - the minimum key value.
        max - the maximum key value.
        dflt - beginning of the default handler block.
        labels - beginnings of the handler blocks. labels[i] is the beginning of the handler block for the min + i key.

      • visitLookupSwitchInsn

        public void visitLookupSwitchInsn​(Label dflt,
                                  int[] keys,
                                  Label[] labels)
        Description copied from class: MethodVisitor
        Visits a LOOKUPSWITCH instruction.
        Overrides:
        visitLookupSwitchInsn in class MethodVisitor
        Parameters:
        dflt - beginning of the default handler block.
        keys - the values of the keys.
        labels - beginnings of the handler blocks. labels[i] is the beginning of the handler block for the keys[i] key.

      • visitSwitchInsn

        private void visitSwitchInsn​(Label dflt,
                             Label[] labels)

      • visitMultiANewArrayInsn

        public void visitMultiANewArrayInsn​(java.lang.String desc,
                                    int dims)
        Description copied from class: MethodVisitor
        Visits a MULTIANEWARRAY instruction.
        Overrides:
        visitMultiANewArrayInsn in class MethodVisitor
        Parameters:
        desc - an array type descriptor (see Type).
        dims - number of dimensions of the array to allocate.

      • visitTryCatchBlock

        public void visitTryCatchBlock​(Label start,
                               Label end,
                               Label handler,
                               java.lang.String type)
        Description copied from class: MethodVisitor
        Visits a try catch block.
        Overrides:
        visitTryCatchBlock in class MethodVisitor
        Parameters:
        start - beginning of the exception handler's scope (inclusive).
        end - end of the exception handler's scope (exclusive).
        handler - beginning of the exception handler's code.
        type - internal name of the type of exceptions handled by the handler, or null to catch any exceptions (for "finally" blocks).

      • visitLocalVariable

        public void visitLocalVariable​(java.lang.String name,
                               java.lang.String desc,
                               java.lang.String signature,
                               Label start,
                               Label end,
                               int index)
        Description copied from class: MethodVisitor
        Visits a local variable declaration.
        Overrides:
        visitLocalVariable in class MethodVisitor
        Parameters:
        name - the name of a local variable.
        desc - the type descriptor of this local variable.
        signature - the type signature of this local variable. May be null if the local variable type does not use generic types.
        start - the first instruction corresponding to the scope of this local variable (inclusive).
        end - the last instruction corresponding to the scope of this local variable (exclusive).
        index - the local variable's index.

      • visitLocalVariableAnnotation

        public AnnotationVisitor visitLocalVariableAnnotation​(int typeRef,
                                                      TypePath typePath,
                                                      Label[] start,
                                                      Label[] end,
                                                      int[] index,
                                                      java.lang.String desc,
                                                      boolean visible)
        Description copied from class: MethodVisitor
        Visits an annotation on a local variable type.
        Overrides:
        visitLocalVariableAnnotation in class MethodVisitor
        Parameters:
        typeRef - a reference to the annotated type. The sort of this type reference must be LOCAL_VARIABLE or RESOURCE_VARIABLE. See TypeReference.
        typePath - the path to the annotated type argument, wildcard bound, array element type, or static inner type within 'typeRef'. May be null if the annotation targets 'typeRef' as a whole.
        start - the fist instructions corresponding to the continuous ranges that make the scope of this local variable (inclusive).
        end - the last instructions corresponding to the continuous ranges that make the scope of this local variable (exclusive). This array must have the same size as the 'start' array.
        index - the local variable's index in each range. This array must have the same size as the 'start' array.
        desc - the class descriptor of the annotation class.
        visible - true if the annotation is visible at runtime.
        Returns:
        a visitor to visit the annotation values, or null if this visitor is not interested in visiting this annotation.

      • visitLineNumber

        public void visitLineNumber​(int line,
                            Label start)
        Description copied from class: MethodVisitor
        Visits a line number declaration.
        Overrides:
        visitLineNumber in class MethodVisitor
        Parameters:
        line - a line number. This number refers to the source file from which the class was compiled.
        start - the first instruction corresponding to this line number.

      • visitMaxs

        public void visitMaxs​(int maxStack,
                      int maxLocals)
        Description copied from class: MethodVisitor
        Visits the maximum stack size and the maximum number of local variables of the method.
        Overrides:
        visitMaxs in class MethodVisitor
        Parameters:
        maxStack - maximum stack size of the method.
        maxLocals - maximum number of local variables for the method.

      • visitEnd

        public void visitEnd()
        Description copied from class: MethodVisitor
        Visits the end of the method. This method, which is the last one to be called, is used to inform the visitor that all the annotations and attributes of the method have been visited.
        Overrides:
        visitEnd in class MethodVisitor

      • addSuccessor

        private void addSuccessor​(int info,
                          Label successor)
        Adds a successor to the currentBlock block.
        Parameters:
        info - information about the control flow edge to be added.
        successor - the successor block to be added to the current block.

      • noSuccessor

        private void noSuccessor()
        Ends the current basic block. This method must be used in the case where the current basic block does not have any successor.

      • visitFrame

        private void visitFrame​(Frame f)
        Visits a frame that has been computed from scratch.
        Parameters:
        f - the frame that must be visited.

      • visitImplicitFirstFrame

        private void visitImplicitFirstFrame()
        Visit the implicit first frame of this method.

      • startFrame

        private int startFrame​(int offset,
                       int nLocal,
                       int nStack)
        Starts the visit of a stack map frame.
        Parameters:
        offset - the offset of the instruction to which the frame corresponds.
        nLocal - the number of local variables in the frame.
        nStack - the number of stack elements in the frame.
        Returns:
        the index of the next element to be written in this frame.

      • endFrame

        private void endFrame()
        Checks if the visit of the current frame frame is finished, and if yes, write it in the StackMapTable attribute.

      • writeFrame

        private void writeFrame()
        Compress and writes the current frame frame in the StackMapTable attribute.

      • writeFrameTypes

        private void writeFrameTypes​(int start,
                             int end)
        Writes some types of the current frame frame into the StackMapTableAttribute. This method converts types from the format used in Label to the format used in StackMapTable attributes. In particular, it converts type table indexes to constant pool indexes.
        Parameters:
        start - index of the first type in frame to write.
        end - index of last type in frame to write (exclusive).

      • writeFrameType

        private void writeFrameType​(java.lang.Object type)

      • getSize

        final int getSize()
        Returns the size of the bytecode of this method.
        Returns:
        the size of the bytecode of this method.

      • put

        final void put​(ByteVector out)
        Puts the bytecode of this method in the given byte vector.
        Parameters:
        out - the byte vector into which the bytecode of this method must be copied.

      • resizeInstructions

        private void resizeInstructions()
        Resizes and replaces the temporary instructions inserted by Label.resolve(org.eclipse.sisu.space.asm.MethodWriter, int, byte[]) for wide forward jumps, while keeping jump offsets and instruction addresses consistent. This may require to resize other existing instructions, or even to introduce new instructions: for example, increasing the size of an instruction by 2 at the middle of a method can increases the offset of an IFEQ instruction from 32766 to 32768, in which case IFEQ 32766 must be replaced with IFNEQ 8 GOTO_W 32765. This, in turn, may require to increase the size of another jump instruction, and so on... All these operations are handled automatically by this method.

        This method must be called after all the method that is being built has been visited. In particular, the Label objects used to construct the method are no longer valid after this method has been called.

      • readUnsignedShort

        static int readUnsignedShort​(byte[] b,
                             int index)
        Reads an unsigned short value in the given byte array.
        Parameters:
        b - a byte array.
        index - the start index of the value to be read.
        Returns:
        the read value.

      • readShort

        static short readShort​(byte[] b,
                       int index)
        Reads a signed short value in the given byte array.
        Parameters:
        b - a byte array.
        index - the start index of the value to be read.
        Returns:
        the read value.

      • readInt

        static int readInt​(byte[] b,
                   int index)
        Reads a signed int value in the given byte array.
        Parameters:
        b - a byte array.
        index - the start index of the value to be read.
        Returns:
        the read value.

      • writeShort

        static void writeShort​(byte[] b,
                       int index,
                       int s)
        Writes a short value in the given byte array.
        Parameters:
        b - a byte array.
        index - where the first byte of the short value must be written.
        s - the value to be written in the given byte array.

      • getNewOffset

        static int getNewOffset​(int[] indexes,
                        int[] sizes,
                        int begin,
                        int end)
        Computes the future value of a bytecode offset.

        Note: it is possible to have several entries for the same instruction in the indexes and sizes: two entries (index=a,size=b) and (index=a,size=b') are equivalent to a single entry (index=a,size=b+b').

        Parameters:
        indexes - current positions of the instructions to be resized. Each instruction must be designated by the index of its last byte, plus one (or, in other words, by the index of the first byte of the next instruction).
        sizes - the number of bytes to be added to the above instructions. More precisely, for each i < len, sizes[i] bytes will be added at the end of the instruction designated by indexes[i] or, if sizes[i] is negative, the last | sizes[i]| bytes of the instruction will be removed (the instruction size must not become negative or null).
        begin - index of the first byte of the source instruction.
        end - index of the first byte of the target instruction.
        Returns:
        the future value of the given bytecode offset.

      • getNewOffset

        static void getNewOffset​(int[] indexes,
                         int[] sizes,
                         Label label)
        Updates the offset of the given label.
        Parameters:
        indexes - current positions of the instructions to be resized. Each instruction must be designated by the index of its last byte, plus one (or, in other words, by the index of the first byte of the next instruction).
        sizes - the number of bytes to be added to the above instructions. More precisely, for each i < len, sizes[i] bytes will be added at the end of the instruction designated by indexes[i] or, if sizes[i] is negative, the last | sizes[i]| bytes of the instruction will be removed (the instruction size must not become negative or null).
        label - the label whose offset must be updated.