org.objectweb.asm.util

Class PrintCodeVisitor

public abstract class PrintCodeVisitor extends Object implements CodeVisitor

An abstract code visitor that prints the code it visits. Each visitXXX method clears the {@link #buf buf} buffer, calls the corresponding printXXX method, and then adds the buffer's content to the {@link #text text} list. In order to provide a concrete print code visitor, one must implement the printXXX methods in a sub class of this class. Each method should print the instructions it visits in {@link #buf buf}.

Author: Eric Bruneton, Eugene Kuleshov

Field Summary
protected StringBufferbuf
A buffer used to convert instructions to strings.
static String[]OPCODES
The names of the Java Virtual Machine opcodes.
protected Listtext
The text to be printed.
Constructor Summary
protected PrintCodeVisitor()
Constructs a new {@link PrintCodeVisitor PrintCodeVisitor} object.
Method Summary
ListgetText()
Returns the code printed by this code visitor.
abstract voidprintAttribute(Attribute attr)
Prints a non standard code attribute.
abstract voidprintFieldInsn(int opcode, String owner, String name, String desc)
Prints a field instruction.
abstract voidprintIincInsn(int var, int increment)
Prints an IINC instruction.
abstract voidprintInsn(int opcode)
Prints a zero operand instruction.
abstract voidprintIntInsn(int opcode, int operand)
Prints an instruction with a single int operand.
abstract voidprintJumpInsn(int opcode, Label label)
Prints a jump instruction.
abstract voidprintLabel(Label label)
Prints a label.
abstract voidprintLdcInsn(Object cst)
Prints a LDC instruction.
abstract voidprintLineNumber(int line, Label start)
Prints a line number declaration.
abstract voidprintLocalVariable(String name, String desc, Label start, Label end, int index)
Prints a local variable declaration.
abstract voidprintLookupSwitchInsn(Label dflt, int[] keys, Label[] labels)
Prints a LOOKUPSWITCH instruction.
abstract voidprintMaxs(int maxStack, int maxLocals)
Prints the maximum stack size and the maximum number of local variables of the method.
abstract voidprintMethodInsn(int opcode, String owner, String name, String desc)
Prints a method instruction.
abstract voidprintMultiANewArrayInsn(String desc, int dims)
Prints a MULTIANEWARRAY instruction.
abstract voidprintTableSwitchInsn(int min, int max, Label dflt, Label[] labels)
Prints a TABLESWITCH instruction.
abstract voidprintTryCatchBlock(Label start, Label end, Label handler, String type)
Prints a try catch block.
abstract voidprintTypeInsn(int opcode, String desc)
Prints a type instruction.
abstract voidprintVarInsn(int opcode, int var)
Prints a local variable instruction.
voidvisitAttribute(Attribute attr)
voidvisitFieldInsn(int opcode, String owner, String name, String desc)
voidvisitIincInsn(int var, int increment)
voidvisitInsn(int opcode)
voidvisitIntInsn(int opcode, int operand)
voidvisitJumpInsn(int opcode, Label label)
voidvisitLabel(Label label)
voidvisitLdcInsn(Object cst)
voidvisitLineNumber(int line, Label start)
voidvisitLocalVariable(String name, String desc, Label start, Label end, int index)
voidvisitLookupSwitchInsn(Label dflt, int[] keys, Label[] labels)
voidvisitMaxs(int maxStack, int maxLocals)
voidvisitMethodInsn(int opcode, String owner, String name, String desc)
voidvisitMultiANewArrayInsn(String desc, int dims)
voidvisitTableSwitchInsn(int min, int max, Label dflt, Label[] labels)
voidvisitTryCatchBlock(Label start, Label end, Label handler, String type)
voidvisitTypeInsn(int opcode, String desc)
voidvisitVarInsn(int opcode, int var)

Field Detail

buf

protected final StringBuffer buf
A buffer used to convert instructions to strings.

OPCODES

public static final String[] OPCODES
The names of the Java Virtual Machine opcodes.

text

protected final List text
The text to be printed. See {@link PrintClassVisitor#text text}.

Constructor Detail

PrintCodeVisitor

protected PrintCodeVisitor()
Constructs a new {@link PrintCodeVisitor PrintCodeVisitor} object.

Method Detail

getText

public List getText()
Returns the code printed by this code visitor.

Returns: the code printed by this code visitor. See {@link PrintClassVisitor#text text}.

printAttribute

public abstract void printAttribute(Attribute attr)
Prints a non standard code attribute.

Parameters: attr a non standard code attribute.

printFieldInsn

public abstract void printFieldInsn(int opcode, String owner, String name, String desc)
Prints a field instruction. A field instruction is an instruction that loads or stores the value of a field of an object.

Parameters: opcode the opcode of the type instruction to be printed. This opcode is either GETSTATIC, PUTSTATIC, GETFIELD or PUTFIELD. owner the internal name of the field's owner class (see {@link org.objectweb.asm.Type#getInternalName() getInternalName}). name the field's name. desc the field's descriptor (see {@link org.objectweb.asm.Type Type}).

printIincInsn

public abstract void printIincInsn(int var, int increment)
Prints an IINC instruction.

Parameters: var index of the local variable to be incremented. increment amount to increment the local variable by.

printInsn

public abstract void printInsn(int opcode)
Prints a zero operand instruction.

Parameters: opcode the opcode of the instruction to be printed. 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.

printIntInsn

public abstract void printIntInsn(int opcode, int operand)
Prints an instruction with a single int operand.

Parameters: opcode the opcode of the instruction to be printed. This opcode is either BIPUSH, SIPUSH or NEWARRAY. operand the operand of the instruction to be printed.

printJumpInsn

public abstract void printJumpInsn(int opcode, Label label)
Prints a jump instruction. A jump instruction is an instruction that may jump to another instruction.

Parameters: opcode the opcode of the type instruction to be printed. 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 printed. This operand is a label that designates the instruction to which the jump instruction may jump.

printLabel

public abstract void printLabel(Label label)
Prints a label. A label designates the instruction that will be visited just after it.

Parameters: label a {@link Label Label} object.

printLdcInsn

public abstract void printLdcInsn(Object cst)
Prints a LDC instruction.

Parameters: cst the constant to be loaded on the stack. This parameter must be a non null {@link java.lang.Integer Integer}, a {@link java.lang.Float Float}, a {@link java.lang.Long Long}, a {@link java.lang.Double Double} or a {@link String String}.

printLineNumber

public abstract void printLineNumber(int line, Label start)
Prints a line number declaration.

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.

printLocalVariable

public abstract void printLocalVariable(String name, String desc, Label start, Label end, int index)
Prints a local variable declaration.

Parameters: name the name of a local variable. desc the type descriptor of this local variable. 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.

printLookupSwitchInsn

public abstract void printLookupSwitchInsn(Label dflt, int[] keys, Label[] labels)
Prints a LOOKUPSWITCH instruction.

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.

printMaxs

public abstract void printMaxs(int maxStack, int maxLocals)
Prints the maximum stack size and the maximum number of local variables of the method.

Parameters: maxStack maximum stack size of the method. maxLocals maximum number of local variables for the method.

printMethodInsn

public abstract void printMethodInsn(int opcode, String owner, String name, String desc)
Prints a method instruction. A method instruction is an instruction that invokes a method.

Parameters: opcode the opcode of the type instruction to be printed. This opcode is either INVOKEVIRTUAL, INVOKESPECIAL, INVOKESTATIC or INVOKEINTERFACE. owner the internal name of the method's owner class (see {@link org.objectweb.asm.Type#getInternalName() getInternalName}). name the method's name. desc the method's descriptor (see {@link org.objectweb.asm.Type Type}).

printMultiANewArrayInsn

public abstract void printMultiANewArrayInsn(String desc, int dims)
Prints a MULTIANEWARRAY instruction.

Parameters: desc an array type descriptor (see {@link org.objectweb.asm.Type Type}). dims number of dimensions of the array to allocate.

printTableSwitchInsn

public abstract void printTableSwitchInsn(int min, int max, Label dflt, Label[] labels)
Prints a TABLESWITCH instruction.

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.

printTryCatchBlock

public abstract void printTryCatchBlock(Label start, Label end, Label handler, String type)
Prints a try catch block.

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).

printTypeInsn

public abstract void printTypeInsn(int opcode, String desc)
Prints a type instruction. A type instruction is an instruction that takes a type descriptor as parameter.

Parameters: opcode the opcode of the type instruction to be printed. This opcode is either NEW, ANEWARRAY, CHECKCAST or INSTANCEOF. desc the operand of the instruction to be printed. This operand is must be a fully qualified class name in internal form, or a the type descriptor of an array type (see {@link org.objectweb.asm.Type Type}).

printVarInsn

public abstract void printVarInsn(int opcode, int var)
Prints a local variable instruction. A local variable instruction is an instruction that loads or stores the value of a local variable.

Parameters: opcode the opcode of the local variable instruction to be printed. This opcode is either ILOAD, LLOAD, FLOAD, DLOAD, ALOAD, ISTORE, LSTORE, FSTORE, DSTORE, ASTORE or RET. var the operand of the instruction to be printed. This operand is the index of a local variable.

visitAttribute

public void visitAttribute(Attribute attr)

visitFieldInsn

public void visitFieldInsn(int opcode, String owner, String name, String desc)

visitIincInsn

public void visitIincInsn(int var, int increment)

visitInsn

public void visitInsn(int opcode)

visitIntInsn

public void visitIntInsn(int opcode, int operand)

visitJumpInsn

public void visitJumpInsn(int opcode, Label label)

visitLabel

public void visitLabel(Label label)

visitLdcInsn

public void visitLdcInsn(Object cst)

visitLineNumber

public void visitLineNumber(int line, Label start)

visitLocalVariable

public void visitLocalVariable(String name, String desc, Label start, Label end, int index)

visitLookupSwitchInsn

public void visitLookupSwitchInsn(Label dflt, int[] keys, Label[] labels)

visitMaxs

public void visitMaxs(int maxStack, int maxLocals)

visitMethodInsn

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

visitMultiANewArrayInsn

public void visitMultiANewArrayInsn(String desc, int dims)

visitTableSwitchInsn

public void visitTableSwitchInsn(int min, int max, Label dflt, Label[] labels)

visitTryCatchBlock

public void visitTryCatchBlock(Label start, Label end, Label handler, String type)

visitTypeInsn

public void visitTypeInsn(int opcode, String desc)

visitVarInsn

public void visitVarInsn(int opcode, int var)