/***
* ASM: a very small and fast Java bytecode manipulation framework
* Copyright (c) 2000-2011 INRIA, France Telecom
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
package immibis.bon.org.objectweb.asm;
/**
* A visitor to visit a Java method. The methods of this class must be
* called in the following order: [ <tt>visitAnnotationDefault</tt> ] (
* <tt>visitAnnotation</tt> | <tt>visitParameterAnnotation</tt> |
* <tt>visitAttribute</tt> )* [ <tt>visitCode</tt> ( <tt>visitFrame</tt> |
* <tt>visit</tt><i>X</i>Insn</tt> | <tt>visitLabel</tt> | <tt>visitTryCatchBlock</tt> |
* <tt>visitLocalVariable</tt> | <tt>visitLineNumber</tt> )* <tt>visitMaxs</tt> ]
* <tt>visitEnd</tt>. In addition, the <tt>visit</tt><i>X</i>Insn</tt>
* and <tt>visitLabel</tt> methods must be called in the sequential order of
* the bytecode instructions of the visited code, <tt>visitTryCatchBlock</tt>
* must be called <i>before</i> the labels passed as arguments have been
* visited, and the <tt>visitLocalVariable</tt> and <tt>visitLineNumber</tt>
* methods must be called <i>after</i> the labels passed as arguments have been
* visited.
*
* @author Eric Bruneton
*/
public abstract class MethodVisitor {
/**
* The ASM API version implemented by this visitor. The value of this field
* must be one of {@link Opcodes#ASM4}.
*/
protected final int api;
/**
* The method visitor to which this visitor must delegate method calls. May
* be null.
*/
protected MethodVisitor mv;
/**
* Constructs a new {@link MethodVisitor}.
*
* @param api the ASM API version implemented by this visitor. Must be one
* of {@link Opcodes#ASM4}.
*/
public MethodVisitor(final int api) {
this(api, null);
}
/**
* Constructs a new {@link MethodVisitor}.
*
* @param api the ASM API version implemented by this visitor. Must be one
* of {@link Opcodes#ASM4}.
* @param mv the method visitor to which this visitor must delegate method
* calls. May be null.
*/
public MethodVisitor(final int api, final MethodVisitor mv) {
/*if (api != Opcodes.ASM4) {
throw new IllegalArgumentException();
}*/
this.api = api;
this.mv = mv;
}
// -------------------------------------------------------------------------
// Annotations and non standard attributes
// -------------------------------------------------------------------------
/**
* Visits the default value of this annotation interface method.
*
* @return a visitor to the visit the actual default value of this
* annotation interface method, or <tt>null</tt> 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.
*/
public AnnotationVisitor visitAnnotationDefault() {
if (mv != null) {
return mv.visitAnnotationDefault();
}
return null;
}
/**
* Visits an annotation of this method.
*
* @param desc the class descriptor of the annotation class.
* @param visible <tt>true</tt> if the annotation is visible at runtime.
* @return a visitor to visit the annotation values, or <tt>null</tt> if
* this visitor is not interested in visiting this annotation.
*/
public AnnotationVisitor visitAnnotation(String desc, boolean visible) {
if (mv != null) {
return mv.visitAnnotation(desc, visible);
}
return null;
}
/**
* Visits an annotation of a parameter this method.
*
* @param parameter the parameter index.
* @param desc the class descriptor of the annotation class.
* @param visible <tt>true</tt> if the annotation is visible at runtime.
* @return a visitor to visit the annotation values, or <tt>null</tt> if
* this visitor is not interested in visiting this annotation.
*/
public AnnotationVisitor visitParameterAnnotation(
int parameter,
String desc,
boolean visible)
{
if (mv != null) {
return mv.visitParameterAnnotation(parameter, desc, visible);
}
return null;
}
/**
* Visits a non standard attribute of this method.
*
* @param attr an attribute.
*/
public void visitAttribute(Attribute attr) {
if (mv != null) {
mv.visitAttribute(attr);
}
}
/**
* Starts the visit of the method's code, if any (i.e. non abstract method).
*/
public void visitCode() {
if (mv != null) {
mv.visitCode();
}
}
/**
* Visits the current state of the local variables and operand stack
* elements. This method must(*) be called <i>just before</i> any
* instruction <b>i</b> 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 <i>just
* before</i> <b>i</b> is executed. <br> <br> (*) this is mandatory only
* for classes whose version is greater than or equal to
* {@link Opcodes#V1_6 V1_6}. <br> <br> Packed frames are basically
* "deltas" from the state of the previous frame (very first frame is
* implicitly defined by the method's parameters and access flags): <ul>
* <li>{@link Opcodes#F_SAME} representing frame with exactly the same
* locals as the previous frame and with the empty stack.</li> <li>{@link Opcodes#F_SAME1}
* representing frame with exactly the same locals as the previous frame and
* with single value on the stack (<code>nStack</code> is 1 and
* <code>stack[0]</code> contains value for the type of the stack item).</li>
* <li>{@link Opcodes#F_APPEND} representing frame with current locals are
* the same as the locals in the previous frame, except that additional
* locals are defined (<code>nLocal</code> is 1, 2 or 3 and
* <code>local</code> elements contains values representing added types).</li>
* <li>{@link 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 (<code>nLocals</code> is 1,
* 2 or 3). </li> <li>{@link Opcodes#F_FULL} representing complete frame
* data.</li> </li> </ul>
*
* @param type the type of this stack map frame. Must be
* {@link Opcodes#F_NEW} for expanded frames, or
* {@link Opcodes#F_FULL}, {@link Opcodes#F_APPEND},
* {@link Opcodes#F_CHOP}, {@link Opcodes#F_SAME} or
* {@link Opcodes#F_APPEND}, {@link Opcodes#F_SAME1} for compressed
* frames.
* @param nLocal the number of local variables in the visited frame.
* @param local the local variable types in this frame. This array must not
* be modified. Primitive types are represented by
* {@link Opcodes#TOP}, {@link Opcodes#INTEGER},
* {@link Opcodes#FLOAT}, {@link Opcodes#LONG},
* {@link Opcodes#DOUBLE},{@link Opcodes#NULL} or
* {@link 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).
* @param nStack the number of operand stack elements in the visited frame.
* @param stack the operand stack types in this frame. This array must not
* be modified. Its content has the same format as the "local" array.
* @throws IllegalStateException if a frame is visited just after another
* one, without any instruction between the two (unless this frame
* is a Opcodes#F_SAME frame, in which case it is silently ignored).
*/
public void visitFrame(
int type,
int nLocal,
Object[] local,
int nStack,
Object[] stack)
{
if (mv != null) {
mv.visitFrame(type, nLocal, local, nStack, stack);
}
}
// -------------------------------------------------------------------------
// Normal instructions
// -------------------------------------------------------------------------
/**
* Visits a zero operand instruction.
*
* @param 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.
*/
public void visitInsn(int opcode) {
if (mv != null) {
mv.visitInsn(opcode);
}
}
/**
* Visits an instruction with a single int operand.
*
* @param opcode the opcode of the instruction to be visited. This opcode is
* either BIPUSH, SIPUSH or NEWARRAY.
* @param operand the operand of the instruction to be visited.<br> When
* opcode is BIPUSH, operand value should be between Byte.MIN_VALUE
* and Byte.MAX_VALUE.<br> When opcode is SIPUSH, operand value
* should be between Short.MIN_VALUE and Short.MAX_VALUE.<br> When
* opcode is NEWARRAY, operand value should be one of
* {@link Opcodes#T_BOOLEAN}, {@link Opcodes#T_CHAR},
* {@link Opcodes#T_FLOAT}, {@link Opcodes#T_DOUBLE},
* {@link Opcodes#T_BYTE}, {@link Opcodes#T_SHORT},
* {@link Opcodes#T_INT} or {@link Opcodes#T_LONG}.
*/
public void visitIntInsn(int opcode, int operand) {
if (mv != null) {
mv.visitIntInsn(opcode, operand);
}
}
/**
* Visits a local variable instruction. A local variable instruction is an
* instruction that loads or stores the value of a local variable.
*
* @param 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.
* @param var the operand of the instruction to be visited. This operand is
* the index of a local variable.
*/
public void visitVarInsn(int opcode, int var) {
if (mv != null) {
mv.visitVarInsn(opcode, var);
}
}
/**
* Visits a type instruction. A type instruction is an instruction that
* takes the internal name of a class as parameter.
*
* @param opcode the opcode of the type instruction to be visited. This
* opcode is either NEW, ANEWARRAY, CHECKCAST or INSTANCEOF.
* @param type the operand of the instruction to be visited. This operand
* must be the internal name of an object or array class (see {@link
* Type#getInternalName() getInternalName}).
*/
public void visitTypeInsn(int opcode, String type) {
if (mv != null) {
mv.visitTypeInsn(opcode, type);
}
}
/**
* Visits a field instruction. A field instruction is an instruction that
* loads or stores the value of a field of an object.
*
* @param opcode the opcode of the type instruction to be visited. This
* opcode is either GETSTATIC, PUTSTATIC, GETFIELD or PUTFIELD.
* @param owner the internal name of the field's owner class (see {@link
* Type#getInternalName() getInternalName}).
* @param name the field's name.
* @param desc the field's descriptor (see {@link Type Type}).
*/
public void visitFieldInsn(int opcode, String owner, String name, String desc) {
if (mv != null) {
mv.visitFieldInsn(opcode, owner, name, desc);
}
}
/**
* Visits a method instruction. A method instruction is an instruction that
* invokes a method.
*
* @param opcode the opcode of the type instruction to be visited. This
* opcode is either INVOKEVIRTUAL, INVOKESPECIAL, INVOKESTATIC
* or INVOKEINTERFACE.
* @param owner the internal name of the method's owner class (see {@link
* Type#getInternalName() getInternalName}).
* @param name the method's name.
* @param desc the method's descriptor (see {@link Type Type}).
*/
public void visitMethodInsn(int opcode, String owner, String name, String desc) {
if (mv != null) {
mv.visitMethodInsn(opcode, owner, name, desc);
}
}
/**
* Visits an invokedynamic instruction.
*
* @param name the method's name.
* @param desc the method's descriptor (see {@link Type Type}).
* @param bsm the bootstrap method.
* @param bsmArgs the bootstrap method constant arguments. Each argument
* must be an {@link Integer}, {@link Float}, {@link Long},
* {@link Double}, {@link String}, {@link Type} or {@link Handle}
* value. This method is allowed to modify the content of the array
* so a caller should expect that this array may change.
*/
public void visitInvokeDynamicInsn(String name, String desc, Handle bsm, Object... bsmArgs) {
if (mv != null) {
mv.visitInvokeDynamicInsn(name, desc, bsm, bsmArgs);
}
}
/**
* Visits a jump instruction. A jump instruction is an instruction that may
* jump to another instruction.
*
* @param 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.
* @param 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.
*/
public void visitJumpInsn(int opcode, Label label) {
if (mv != null) {
mv.visitJumpInsn(opcode, label);
}
}
/**
* Visits a label. A label designates the instruction that will be visited
* just after it.
*
* @param label a {@link Label Label} object.
*/
public void visitLabel(Label label) {
if (mv != null) {
mv.visitLabel(label);
}
}
// -------------------------------------------------------------------------
// Special instructions
// -------------------------------------------------------------------------
/**
* 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:
* <pre>
* 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
* }</pre>
*
* @param cst the constant to be loaded on the stack. This parameter must be
* a non null {@link Integer}, a {@link Float}, a {@link Long}, a
* {@link Double}, a {@link String}, a {@link Type} of OBJECT or ARRAY
* sort for <tt>.class</tt> constants, for classes whose version is
* 49.0, a {@link Type} of METHOD sort or a {@link Handle} for
* MethodType and MethodHandle constants, for classes whose version
* is 51.0.
*/
public void visitLdcInsn(Object cst) {
if (mv != null) {
mv.visitLdcInsn(cst);
}
}
/**
* Visits an IINC instruction.
*
* @param var index of the local variable to be incremented.
* @param increment amount to increment the local variable by.
*/
public void visitIincInsn(int var, int increment) {
if (mv != null) {
mv.visitIincInsn(var, increment);
}
}
/**
* Visits a TABLESWITCH instruction.
*
* @param min the minimum key value.
* @param max the maximum key value.
* @param dflt beginning of the default handler block.
* @param labels beginnings of the handler blocks. <tt>labels[i]</tt> is
* the beginning of the handler block for the <tt>min + i</tt> key.
*/
public void visitTableSwitchInsn(int min, int max, Label dflt, Label... labels) {
if (mv != null) {
mv.visitTableSwitchInsn(min, max, dflt, labels);
}
}
/**
* Visits a LOOKUPSWITCH instruction.
*
* @param dflt beginning of the default handler block.
* @param keys the values of the keys.
* @param labels beginnings of the handler blocks. <tt>labels[i]</tt> is
* the beginning of the handler block for the <tt>keys[i]</tt> key.
*/
public void visitLookupSwitchInsn(Label dflt, int[] keys, Label[] labels) {
if (mv != null) {
mv.visitLookupSwitchInsn(dflt, keys, labels);
}
}
/**
* Visits a MULTIANEWARRAY instruction.
*
* @param desc an array type descriptor (see {@link Type Type}).
* @param dims number of dimensions of the array to allocate.
*/
public void visitMultiANewArrayInsn(String desc, int dims) {
if (mv != null) {
mv.visitMultiANewArrayInsn(desc, dims);
}
}
// -------------------------------------------------------------------------
// Exceptions table entries, debug information, max stack and max locals
// -------------------------------------------------------------------------
/**
* Visits a try catch block.
*
* @param start beginning of the exception handler's scope (inclusive).
* @param end end of the exception handler's scope (exclusive).
* @param handler beginning of the exception handler's code.
* @param type internal name of the type of exceptions handled by the
* handler, or <tt>null</tt> to catch any exceptions (for "finally"
* blocks).
* @throws IllegalArgumentException if one of the labels has already been
* visited by this visitor (by the {@link #visitLabel visitLabel}
* method).
*/
public void visitTryCatchBlock(Label start, Label end, Label handler, String type) {
if (mv != null) {
mv.visitTryCatchBlock(start, end, handler, type);
}
}
/**
* Visits a local variable declaration.
*
* @param name the name of a local variable.
* @param desc the type descriptor of this local variable.
* @param signature the type signature of this local variable. May be
* <tt>null</tt> if the local variable type does not use generic
* types.
* @param start the first instruction corresponding to the scope of this
* local variable (inclusive).
* @param end the last instruction corresponding to the scope of this local
* variable (exclusive).
* @param index the local variable's index.
* @throws IllegalArgumentException if one of the labels has not already
* been visited by this visitor (by the
* {@link #visitLabel visitLabel} method).
*/
public void visitLocalVariable(
String name,
String desc,
String signature,
Label start,
Label end,
int index)
{
if (mv != null) {
mv.visitLocalVariable(name, desc, signature, start, end, index);
}
}
/**
* Visits a line number declaration.
*
* @param line a line number. This number refers to the source file from
* which the class was compiled.
* @param start the first instruction corresponding to this line number.
* @throws IllegalArgumentException if <tt>start</tt> has not already been
* visited by this visitor (by the {@link #visitLabel visitLabel}
* method).
*/
public void visitLineNumber(int line, Label start) {
if (mv != null) {
mv.visitLineNumber(line, start);
}
}
/**
* Visits the maximum stack size and the maximum number of local variables
* of the method.
*
* @param maxStack maximum stack size of the method.
* @param maxLocals maximum number of local variables for the method.
*/
public void visitMaxs(int maxStack, int maxLocals) {
if (mv != null) {
mv.visitMaxs(maxStack, maxLocals);
}
}
/**
* 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.
*/
public void visitEnd() {
if (mv != null) {
mv.visitEnd();
}
}
}