Class AdviceAdapter

All Implemented Interfaces:
Opcodes

public abstract class AdviceAdapter extends GeneratorAdapter implements Opcodes
A MethodVisitor to insert before, after and around advices in methods and constructors.

The behavior for constructors is like this:

  1. as long as the INVOKESPECIAL for the object initialization has not been reached, every bytecode instruction is dispatched in the ctor code visitor
  2. when this one is reached, it is only added in the ctor code visitor and a JP invoke is added
  3. after that, only the other code visitor receives the instructions
  • Field Details

    • THIS

      private static final Object THIS
    • OTHER

      private static final Object OTHER
    • methodAccess

      protected int methodAccess
    • methodDesc

      protected String methodDesc
    • constructor

      private boolean constructor
    • superInitialized

      private boolean superInitialized
    • stackFrame

      private List<Object> stackFrame
    • branches

      private Map<Label,List<Object>> branches
  • Constructor Details

    • AdviceAdapter

      protected AdviceAdapter(int api, MethodVisitor mv, int access, String name, String desc)
      Creates a new AdviceAdapter.
      Parameters:
      api - the ASM API version implemented by this visitor. Must be one of Opcodes.ASM4.
      mv - the method visitor to which this adapter delegates calls.
      access - the method's access flags (see Opcodes).
      name - the method's name.
      desc - the method's descriptor (see Type).
  • Method Details

    • 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
    • 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.
    • 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 LocalVariablesSorter
      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.
    • visitFieldInsn

      public void visitFieldInsn(int opcode, String owner, String name, 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).
    • visitIntInsn

      public void visitIntInsn(int opcode, int operand)
      Description copied from class: MethodVisitor
      Visits an instruction with a single int operand.
      Overrides:
      visitIntInsn in class MethodVisitor
      Parameters:
      opcode - the opcode of the instruction to be visited. This opcode is either BIPUSH, SIPUSH or NEWARRAY.
      operand - the operand of the instruction to be visited.
      When opcode is BIPUSH, operand value should be between Byte.MIN_VALUE and Byte.MAX_VALUE.
      When opcode is SIPUSH, operand value should be between Short.MIN_VALUE and Short.MAX_VALUE.
      When opcode is NEWARRAY, operand value should be one of Opcodes.T_BOOLEAN, Opcodes.T_CHAR, Opcodes.T_FLOAT, Opcodes.T_DOUBLE, Opcodes.T_BYTE, Opcodes.T_SHORT, Opcodes.T_INT or Opcodes.T_LONG.
    • visitLdcInsn

      public void visitLdcInsn(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.
    • visitMultiANewArrayInsn

      public void visitMultiANewArrayInsn(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.
    • visitTypeInsn

      public void visitTypeInsn(int opcode, 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).
    • visitMethodInsn

      public void visitMethodInsn(int opcode, String owner, String name, String desc)
      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).
    • visitInvokeDynamicInsn

      public void visitInvokeDynamicInsn(String name, String desc, Handle bsm, 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.
    • 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.
    • 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.
    • visitTryCatchBlock

      public void visitTryCatchBlock(Label start, Label end, Label handler, 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).
    • addBranches

      private void addBranches(Label dflt, Label[] labels)
    • addBranch

      private void addBranch(Label label)
    • popValue

      private Object popValue()
    • peekValue

      private Object peekValue()
    • pushValue

      private void pushValue(Object o)
    • onMethodEnter

      protected void onMethodEnter()
      Called at the beginning of the method or after super class class call in the constructor.

      Custom code can use or change all the local variables, but should not change state of the stack.
    • onMethodExit

      protected void onMethodExit(int opcode)
      Called before explicit exit from the method using either return or throw. Top element on the stack contains the return value or exception instance. For example:
         public void onMethodExit(int opcode) {
           if(opcode==RETURN) {
               visitInsn(ACONST_NULL);
           } else if(opcode==ARETURN || opcode==ATHROW) {
               dup();
           } else {
               if(opcode==LRETURN || opcode==DRETURN) {
                   dup2();
               } else {
                   dup();
               }
               box(Type.getReturnType(this.methodDesc));
           }
           visitIntInsn(SIPUSH, opcode);
           visitMethodInsn(INVOKESTATIC, owner, "onExit", "(Ljava/lang/Object;I)V");
         }
      
         // an actual call back method
         public static void onExit(Object param, int opcode) {
           ...
       


      Custom code can use or change all the local variables, but should not change state of the stack.
      Parameters:
      opcode - one of the RETURN, IRETURN, FRETURN, ARETURN, LRETURN, DRETURN or ATHROW