Java tutorial
// 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 org.springframework.asm; /** * A visitor to visit a Java method. The methods of this class must be called in the following * order: ( {@code visitParameter} )* [ {@code visitAnnotationDefault} ] ( {@code visitAnnotation} | * {@code visitAnnotableParameterCount} | {@code visitParameterAnnotation} {@code * visitTypeAnnotation} | {@code visitAttribute} )* [ {@code visitCode} ( {@code visitFrame} | * {@code visit<i>X</i>Insn} | {@code visitLabel} | {@code visitInsnAnnotation} | {@code * visitTryCatchBlock} | {@code visitTryCatchAnnotation} | {@code visitLocalVariable} | {@code * visitLocalVariableAnnotation} | {@code visitLineNumber} )* {@code visitMaxs} ] {@code visitEnd}. * In addition, the {@code visit<i>X</i>Insn} and {@code visitLabel} methods must be called in the * sequential order of the bytecode instructions of the visited code, {@code visitInsnAnnotation} * must be called <i>after</i> the annotated instruction, {@code visitTryCatchBlock} must be called * <i>before</i> the labels passed as arguments have been visited, {@code * visitTryCatchBlockAnnotation} must be called <i>after</i> the corresponding try catch block has * been visited, and the {@code visitLocalVariable}, {@code visitLocalVariableAnnotation} and {@code * visitLineNumber} methods must be called <i>after</i> the labels passed as arguments have been * visited. * * @author Eric Bruneton */ public abstract class MethodVisitor { private static final String REQUIRES_ASM5 = "This feature requires ASM5"; /** * The ASM API version implemented by this visitor. The value of this field must be one of {@link * Opcodes#ASM4}, {@link Opcodes#ASM5}, {@link Opcodes#ASM6} or {@link Opcodes#ASM7}. */ protected final int api; /** * The method visitor to which this visitor must delegate method calls. May be {@literal 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}, {@link Opcodes#ASM5}, {@link Opcodes#ASM6} or {@link Opcodes#ASM7}. */ 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}, {@link Opcodes#ASM5}, {@link Opcodes#ASM6} or {@link Opcodes#ASM7}. * @param methodVisitor the method visitor to which this visitor must delegate method calls. May * be null. */ public MethodVisitor(final int api, final MethodVisitor methodVisitor) { if (api != Opcodes.ASM7 && api != Opcodes.ASM6 && api != Opcodes.ASM5 && api != Opcodes.ASM4) { throw new IllegalArgumentException("Unsupported api " + api); } this.api = api; this.mv = methodVisitor; } // ----------------------------------------------------------------------------------------------- // Parameters, annotations and non standard attributes // ----------------------------------------------------------------------------------------------- /** * Visits a parameter of this method. * * @param name parameter name or {@literal null} if none is provided. * @param access the parameter's access flags, only {@code ACC_FINAL}, {@code ACC_SYNTHETIC} * or/and {@code ACC_MANDATED} are allowed (see {@link Opcodes}). */ public void visitParameter(final String name, final int access) { if (api < Opcodes.ASM5) { throw new UnsupportedOperationException(REQUIRES_ASM5); } if (mv != null) { mv.visitParameter(name, access); } } /** * 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 * {@literal 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. */ public AnnotationVisitor visitAnnotationDefault() { if (mv != null) { return mv.visitAnnotationDefault(); } return null; } /** * Visits an annotation of this method. * * @param descriptor the class descriptor of the annotation class. * @param visible {@literal true} if the annotation is visible at runtime. * @return a visitor to visit the annotation values, or {@literal null} if this visitor is not * interested in visiting this annotation. */ public AnnotationVisitor visitAnnotation(final String descriptor, final boolean visible) { if (mv != null) { return mv.visitAnnotation(descriptor, visible); } return null; } /** * Visits an annotation on a type in the method signature. * * @param typeRef a reference to the annotated type. The sort of this type reference must be * {@link TypeReference#METHOD_TYPE_PARAMETER}, {@link * TypeReference#METHOD_TYPE_PARAMETER_BOUND}, {@link TypeReference#METHOD_RETURN}, {@link * TypeReference#METHOD_RECEIVER}, {@link TypeReference#METHOD_FORMAL_PARAMETER} or {@link * TypeReference#THROWS}. See {@link TypeReference}. * @param typePath the path to the annotated type argument, wildcard bound, array element type, or * static inner type within 'typeRef'. May be {@literal null} if the annotation targets * 'typeRef' as a whole. * @param descriptor the class descriptor of the annotation class. * @param visible {@literal true} if the annotation is visible at runtime. * @return a visitor to visit the annotation values, or {@literal null} if this visitor is not * interested in visiting this annotation. */ public AnnotationVisitor visitTypeAnnotation(final int typeRef, final TypePath typePath, final String descriptor, final boolean visible) { if (api < Opcodes.ASM5) { throw new UnsupportedOperationException(REQUIRES_ASM5); } if (mv != null) { return mv.visitTypeAnnotation(typeRef, typePath, descriptor, visible); } return null; } /** * Visits the number of method parameters that can have annotations. By default (i.e. when this * method is not called), all the method parameters defined by the method descriptor can have * annotations. * * @param parameterCount the number of method parameters than can have annotations. This number * must be less or equal than the number of parameter types in the method descriptor. It can * be strictly less when a method has synthetic parameters and when these parameters are * ignored when computing parameter indices for the purpose of parameter annotations (see * https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.18). * @param visible {@literal true} to define the number of method parameters that can have * annotations visible at runtime, {@literal false} to define the number of method parameters * that can have annotations invisible at runtime. */ public void visitAnnotableParameterCount(final int parameterCount, final boolean visible) { if (mv != null) { mv.visitAnnotableParameterCount(parameterCount, visible); } } /** * Visits an annotation of a parameter this method. * * @param parameter the parameter index. This index must be strictly smaller than the number of * parameters in the method descriptor, and strictly smaller than the parameter count * specified in {@link #visitAnnotableParameterCount}. Important note: <i>a parameter index i * is not required to correspond to the i'th parameter descriptor in the method * descriptor</i>, in particular in case of synthetic parameters (see * https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.18). * @param descriptor the class descriptor of the annotation class. * @param visible {@literal true} if the annotation is visible at runtime. * @return a visitor to visit the annotation values, or {@literal null} if this visitor is not * interested in visiting this annotation. */ public AnnotationVisitor visitParameterAnnotation(final int parameter, final String descriptor, final boolean visible) { if (mv != null) { return mv.visitParameterAnnotation(parameter, descriptor, visible); } return null; } /** * Visits a non standard attribute of this method. * * @param attribute an attribute. */ public void visitAttribute(final Attribute attribute) { if (mv != null) { mv.visitAttribute(attribute); } } /** 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}. <br> * <br> * 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): * * <ul> * <li>In expanded form, all frames must have the F_NEW type. * <li>In compressed form, frames are basically "deltas" from the state of the previous frame: * <ul> * <li>{@link Opcodes#F_SAME} representing frame with exactly the same locals as the * previous frame and with the empty stack. * <li>{@link Opcodes#F_SAME1} representing frame with exactly the same locals as the * previous frame and with single value on the stack ( <code>numStack</code> is 1 and * <code>stack[0]</code> contains value for the type of the stack item). * <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> * numLocal</code> is 1, 2 or 3 and <code>local</code> elements contains values * representing added types). * <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>numLocal</code> is 1, 2 or 3). * <li>{@link Opcodes#F_FULL} representing complete frame data. * </ul> * </ul> * * <br> * 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). * * @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 numLocal 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 numStack 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(final int type, final int numLocal, final Object[] local, final int numStack, final Object[] stack) { if (mv != null) { mv.visitFrame(type, numLocal, local, numStack, 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(final 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(final int opcode, final 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(final int opcode, final 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()}). */ public void visitTypeInsn(final int opcode, final 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()}). * @param name the field's name. * @param descriptor the field's descriptor (see {@link Type}). */ public void visitFieldInsn(final int opcode, final String owner, final String name, final String descriptor) { if (mv != null) { mv.visitFieldInsn(opcode, owner, name, descriptor); } } /** * 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()}). * @param name the method's name. * @param descriptor the method's descriptor (see {@link Type}). * @deprecated use {@link #visitMethodInsn(int, String, String, String, boolean)} instead. */ @Deprecated public void visitMethodInsn(final int opcode, final String owner, final String name, final String descriptor) { int opcodeAndSource = opcode | (api < Opcodes.ASM5 ? Opcodes.SOURCE_DEPRECATED : 0); visitMethodInsn(opcodeAndSource, owner, name, descriptor, opcode == Opcodes.INVOKEINTERFACE); } /** * 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()}). * @param name the method's name. * @param descriptor the method's descriptor (see {@link Type}). * @param isInterface if the method's owner class is an interface. */ public void visitMethodInsn(final int opcode, final String owner, final String name, final String descriptor, final boolean isInterface) { if (api < Opcodes.ASM5 && (opcode & Opcodes.SOURCE_DEPRECATED) == 0) { if (isInterface != (opcode == Opcodes.INVOKEINTERFACE)) { throw new UnsupportedOperationException("INVOKESPECIAL/STATIC on interfaces requires ASM5"); } visitMethodInsn(opcode, owner, name, descriptor); return; } if (mv != null) { mv.visitMethodInsn(opcode & ~Opcodes.SOURCE_MASK, owner, name, descriptor, isInterface); } } /** * Visits an invokedynamic instruction. * * @param name the method's name. * @param descriptor the method's descriptor (see {@link Type}). * @param bootstrapMethodHandle the bootstrap method. * @param bootstrapMethodArguments the bootstrap method constant arguments. Each argument must be * an {@link Integer}, {@link Float}, {@link Long}, {@link Double}, {@link String}, {@link * Type}, {@link Handle} or {@link ConstantDynamic} 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(final String name, final String descriptor, final Handle bootstrapMethodHandle, final Object... bootstrapMethodArguments) { if (api < Opcodes.ASM5) { throw new UnsupportedOperationException(REQUIRES_ASM5); } if (mv != null) { mv.visitInvokeDynamicInsn(name, descriptor, bootstrapMethodHandle, bootstrapMethodArguments); } } /** * 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(final int opcode, final 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} object. */ public void visitLabel(final 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 if (cst instanceof ConstantDynamic) { * // ... * } else { * // throw an exception * } * </pre> * * @param value 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 {@code .class} constants, for classes whose version is * 49, a {@link Type} of METHOD sort for MethodType, a {@link Handle} for MethodHandle * constants, for classes whose version is 51 or a {@link ConstantDynamic} for a constant * dynamic for classes whose version is 55. */ public void visitLdcInsn(final Object value) { if (api < Opcodes.ASM5 && (value instanceof Handle || (value instanceof Type && ((Type) value).getSort() == Type.METHOD))) { throw new UnsupportedOperationException(REQUIRES_ASM5); } if (api != Opcodes.ASM7 && value instanceof ConstantDynamic) { throw new UnsupportedOperationException("This feature requires ASM7"); } if (mv != null) { mv.visitLdcInsn(value); } } /** * 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(final int var, final 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. {@code labels[i]} is the beginning of the * handler block for the {@code min + i} key. */ public void visitTableSwitchInsn(final int min, final int max, final Label dflt, final 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. {@code labels[i]} is the beginning of the * handler block for the {@code keys[i]} key. */ public void visitLookupSwitchInsn(final Label dflt, final int[] keys, final Label[] labels) { if (mv != null) { mv.visitLookupSwitchInsn(dflt, keys, labels); } } /** * Visits a MULTIANEWARRAY instruction. * * @param descriptor an array type descriptor (see {@link Type}). * @param numDimensions the number of dimensions of the array to allocate. */ public void visitMultiANewArrayInsn(final String descriptor, final int numDimensions) { if (mv != null) { mv.visitMultiANewArrayInsn(descriptor, numDimensions); } } /** * Visits an annotation on an instruction. This method must be called just <i>after</i> the * annotated instruction. It can be called several times for the same instruction. * * @param typeRef a reference to the annotated type. The sort of this type reference must be * {@link TypeReference#INSTANCEOF}, {@link TypeReference#NEW}, {@link * TypeReference#CONSTRUCTOR_REFERENCE}, {@link TypeReference#METHOD_REFERENCE}, {@link * TypeReference#CAST}, {@link TypeReference#CONSTRUCTOR_INVOCATION_TYPE_ARGUMENT}, {@link * TypeReference#METHOD_INVOCATION_TYPE_ARGUMENT}, {@link * TypeReference#CONSTRUCTOR_REFERENCE_TYPE_ARGUMENT}, or {@link * TypeReference#METHOD_REFERENCE_TYPE_ARGUMENT}. See {@link TypeReference}. * @param typePath the path to the annotated type argument, wildcard bound, array element type, or * static inner type within 'typeRef'. May be {@literal null} if the annotation targets * 'typeRef' as a whole. * @param descriptor the class descriptor of the annotation class. * @param visible {@literal true} if the annotation is visible at runtime. * @return a visitor to visit the annotation values, or {@literal null} if this visitor is not * interested in visiting this annotation. */ public AnnotationVisitor visitInsnAnnotation(final int typeRef, final TypePath typePath, final String descriptor, final boolean visible) { if (api < Opcodes.ASM5) { throw new UnsupportedOperationException(REQUIRES_ASM5); } if (mv != null) { return mv.visitInsnAnnotation(typeRef, typePath, descriptor, visible); } return null; } // ----------------------------------------------------------------------------------------------- // Exceptions table entries, debug information, max stack and max locals // ----------------------------------------------------------------------------------------------- /** * Visits a try catch block. * * @param start the beginning of the exception handler's scope (inclusive). * @param end the end of the exception handler's scope (exclusive). * @param handler the beginning of the exception handler's code. * @param type the internal name of the type of exceptions handled by the handler, or {@literal * null} 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} method). */ public void visitTryCatchBlock(final Label start, final Label end, final Label handler, final String type) { if (mv != null) { mv.visitTryCatchBlock(start, end, handler, type); } } /** * Visits an annotation on an exception handler type. This method must be called <i>after</i> the * {@link #visitTryCatchBlock} for the annotated exception handler. It can be called several times * for the same exception handler. * * @param typeRef a reference to the annotated type. The sort of this type reference must be * {@link TypeReference#EXCEPTION_PARAMETER}. See {@link TypeReference}. * @param typePath the path to the annotated type argument, wildcard bound, array element type, or * static inner type within 'typeRef'. May be {@literal null} if the annotation targets * 'typeRef' as a whole. * @param descriptor the class descriptor of the annotation class. * @param visible {@literal true} if the annotation is visible at runtime. * @return a visitor to visit the annotation values, or {@literal null} if this visitor is not * interested in visiting this annotation. */ public AnnotationVisitor visitTryCatchAnnotation(final int typeRef, final TypePath typePath, final String descriptor, final boolean visible) { if (api < Opcodes.ASM5) { throw new UnsupportedOperationException(REQUIRES_ASM5); } if (mv != null) { return mv.visitTryCatchAnnotation(typeRef, typePath, descriptor, visible); } return null; } /** * Visits a local variable declaration. * * @param name the name of a local variable. * @param descriptor the type descriptor of this local variable. * @param signature the type signature of this local variable. May be {@literal null} 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} method). */ public void visitLocalVariable(final String name, final String descriptor, final String signature, final Label start, final Label end, final int index) { if (mv != null) { mv.visitLocalVariable(name, descriptor, signature, start, end, index); } } /** * Visits an annotation on a local variable type. * * @param typeRef a reference to the annotated type. The sort of this type reference must be * {@link TypeReference#LOCAL_VARIABLE} or {@link TypeReference#RESOURCE_VARIABLE}. See {@link * TypeReference}. * @param typePath the path to the annotated type argument, wildcard bound, array element type, or * static inner type within 'typeRef'. May be {@literal null} if the annotation targets * 'typeRef' as a whole. * @param start the fist instructions corresponding to the continuous ranges that make the scope * of this local variable (inclusive). * @param 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. * @param index the local variable's index in each range. This array must have the same size as * the 'start' array. * @param descriptor the class descriptor of the annotation class. * @param visible {@literal true} if the annotation is visible at runtime. * @return a visitor to visit the annotation values, or {@literal null} if this visitor is not * interested in visiting this annotation. */ public AnnotationVisitor visitLocalVariableAnnotation(final int typeRef, final TypePath typePath, final Label[] start, final Label[] end, final int[] index, final String descriptor, final boolean visible) { if (api < Opcodes.ASM5) { throw new UnsupportedOperationException(REQUIRES_ASM5); } if (mv != null) { return mv.visitLocalVariableAnnotation(typeRef, typePath, start, end, index, descriptor, visible); } return null; } /** * 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 {@code start} has not already been visited by this visitor * (by the {@link #visitLabel} method). */ public void visitLineNumber(final int line, final 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(final int maxStack, final 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(); } } }