http://git-wip-us.apache.org/repos/asf/tajo/blob/7603a3d4/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/Label.java ---------------------------------------------------------------------- diff --git a/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/Label.java b/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/Label.java new file mode 100644 index 0000000..bf061ba --- /dev/null +++ b/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/Label.java @@ -0,0 +1,560 @@ +/*** + * 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.apache.tajo.org.objectweb.asm; + +/** + * A label represents a position in the bytecode of a method. Labels are used + * for jump, goto, and switch instructions, and for try catch blocks. A label + * designates the <i>instruction</i> that is just after. Note however that there + * can be other elements between a label and the instruction it designates (such + * as other labels, stack map frames, line numbers, etc.). + * + * @author Eric Bruneton + */ +public class Label { + + /** + * Indicates if this label is only used for debug attributes. Such a label + * is not the start of a basic block, the target of a jump instruction, or + * an exception handler. It can be safely ignored in control flow graph + * analysis algorithms (for optimization purposes). + */ + static final int DEBUG = 1; + + /** + * Indicates if the position of this label is known. + */ + static final int RESOLVED = 2; + + /** + * Indicates if this label has been updated, after instruction resizing. + */ + static final int RESIZED = 4; + + /** + * Indicates if this basic block has been pushed in the basic block stack. + * See {@link MethodWriter#visitMaxs visitMaxs}. + */ + static final int PUSHED = 8; + + /** + * Indicates if this label is the target of a jump instruction, or the start + * of an exception handler. + */ + static final int TARGET = 16; + + /** + * Indicates if a stack map frame must be stored for this label. + */ + static final int STORE = 32; + + /** + * Indicates if this label corresponds to a reachable basic block. + */ + static final int REACHABLE = 64; + + /** + * Indicates if this basic block ends with a JSR instruction. + */ + static final int JSR = 128; + + /** + * Indicates if this basic block ends with a RET instruction. + */ + static final int RET = 256; + + /** + * Indicates if this basic block is the start of a subroutine. + */ + static final int SUBROUTINE = 512; + + /** + * Indicates if this subroutine basic block has been visited by a + * visitSubroutine(null, ...) call. + */ + static final int VISITED = 1024; + + /** + * Indicates if this subroutine basic block has been visited by a + * visitSubroutine(!null, ...) call. + */ + static final int VISITED2 = 2048; + + /** + * Field used to associate user information to a label. Warning: this field + * is used by the ASM tree package. In order to use it with the ASM tree + * package you must override the + * {@link org.apache.tajo.org.objectweb.asm.tree.MethodNode#getLabelNode} method. + */ + public Object info; + + /** + * Flags that indicate the status of this label. + * + * @see #DEBUG + * @see #RESOLVED + * @see #RESIZED + * @see #PUSHED + * @see #TARGET + * @see #STORE + * @see #REACHABLE + * @see #JSR + * @see #RET + */ + int status; + + /** + * The line number corresponding to this label, if known. + */ + int line; + + /** + * The position of this label in the code, if known. + */ + int position; + + /** + * Number of forward references to this label, times two. + */ + private int referenceCount; + + /** + * Informations about forward references. Each forward reference is + * described by two consecutive integers in this array: the first one is the + * position of the first byte of the bytecode instruction that contains the + * forward reference, while the second is the position of the first byte of + * the forward reference itself. In fact the sign of the first integer + * indicates if this reference uses 2 or 4 bytes, and its absolute value + * gives the position of the bytecode instruction. This array is also used + * as a bitset to store the subroutines to which a basic block belongs. This + * information is needed in {@linked MethodWriter#visitMaxs}, after all + * forward references have been resolved. Hence the same array can be used + * for both purposes without problems. + */ + private int[] srcAndRefPositions; + + // ------------------------------------------------------------------------ + + /* + * Fields for the control flow and data flow graph analysis algorithms (used + * to compute the maximum stack size or the stack map frames). A control + * flow graph contains one node per "basic block", and one edge per "jump" + * from one basic block to another. Each node (i.e., each basic block) is + * represented by the Label object that corresponds to the first instruction + * of this basic block. Each node also stores the list of its successors in + * the graph, as a linked list of Edge objects. + * + * The control flow analysis algorithms used to compute the maximum stack + * size or the stack map frames are similar and use two steps. The first + * step, during the visit of each instruction, builds information about the + * state of the local variables and the operand stack at the end of each + * basic block, called the "output frame", <i>relatively</i> to the frame + * state at the beginning of the basic block, which is called the "input + * frame", and which is <i>unknown</i> during this step. The second step, in + * {@link MethodWriter#visitMaxs}, is a fix point algorithm that computes + * information about the input frame of each basic block, from the input + * state of the first basic block (known from the method signature), and by + * the using the previously computed relative output frames. + * + * The algorithm used to compute the maximum stack size only computes the + * relative output and absolute input stack heights, while the algorithm + * used to compute stack map frames computes relative output frames and + * absolute input frames. + */ + + /** + * Start of the output stack relatively to the input stack. The exact + * semantics of this field depends on the algorithm that is used. + * + * When only the maximum stack size is computed, this field is the number of + * elements in the input stack. + * + * When the stack map frames are completely computed, this field is the + * offset of the first output stack element relatively to the top of the + * input stack. This offset is always negative or null. A null offset means + * that the output stack must be appended to the input stack. A -n offset + * means that the first n output stack elements must replace the top n input + * stack elements, and that the other elements must be appended to the input + * stack. + */ + int inputStackTop; + + /** + * Maximum height reached by the output stack, relatively to the top of the + * input stack. This maximum is always positive or null. + */ + int outputStackMax; + + /** + * Information about the input and output stack map frames of this basic + * block. This field is only used when {@link ClassWriter#COMPUTE_FRAMES} + * option is used. + */ + Frame frame; + + /** + * The successor of this label, in the order they are visited. This linked + * list does not include labels used for debug info only. If + * {@link ClassWriter#COMPUTE_FRAMES} option is used then, in addition, it + * does not contain successive labels that denote the same bytecode position + * (in this case only the first label appears in this list). + */ + Label successor; + + /** + * The successors of this node in the control flow graph. These successors + * are stored in a linked list of {@link Edge Edge} objects, linked to each + * other by their {@link Edge#next} field. + */ + Edge successors; + + /** + * The next basic block in the basic block stack. This stack is used in the + * main loop of the fix point algorithm used in the second step of the + * control flow analysis algorithms. It is also used in + * {@link #visitSubroutine} to avoid using a recursive method. + * + * @see MethodWriter#visitMaxs + */ + Label next; + + // ------------------------------------------------------------------------ + // Constructor + // ------------------------------------------------------------------------ + + /** + * Constructs a new label. + */ + public Label() { + } + + // ------------------------------------------------------------------------ + // Methods to compute offsets and to manage forward references + // ------------------------------------------------------------------------ + + /** + * Returns the offset corresponding to this label. This offset is computed + * from the start of the method's bytecode. <i>This method is intended for + * {@link Attribute} sub classes, and is normally not needed by class + * generators or adapters.</i> + * + * @return the offset corresponding to this label. + * @throws IllegalStateException + * if this label is not resolved yet. + */ + public int getOffset() { + if ((status & RESOLVED) == 0) { + throw new IllegalStateException( + "Label offset position has not been resolved yet"); + } + return position; + } + + /** + * Puts a reference to this label in the bytecode of a method. If the + * position of the label is known, the offset is computed and written + * directly. Otherwise, a null offset is written and a new forward reference + * is declared for this label. + * + * @param owner + * the code writer that calls this method. + * @param out + * the bytecode of the method. + * @param source + * the position of first byte of the bytecode instruction that + * contains this label. + * @param wideOffset + * <tt>true</tt> if the reference must be stored in 4 bytes, or + * <tt>false</tt> if it must be stored with 2 bytes. + * @throws IllegalArgumentException + * if this label has not been created by the given code writer. + */ + void put(final MethodWriter owner, final ByteVector out, final int source, + final boolean wideOffset) { + if ((status & RESOLVED) == 0) { + if (wideOffset) { + addReference(-1 - source, out.length); + out.putInt(-1); + } else { + addReference(source, out.length); + out.putShort(-1); + } + } else { + if (wideOffset) { + out.putInt(position - source); + } else { + out.putShort(position - source); + } + } + } + + /** + * Adds a forward reference to this label. This method must be called only + * for a true forward reference, i.e. only if this label is not resolved + * yet. For backward references, the offset of the reference can be, and + * must be, computed and stored directly. + * + * @param sourcePosition + * the position of the referencing instruction. This position + * will be used to compute the offset of this forward reference. + * @param referencePosition + * the position where the offset for this forward reference must + * be stored. + */ + private void addReference(final int sourcePosition, + final int referencePosition) { + if (srcAndRefPositions == null) { + srcAndRefPositions = new int[6]; + } + if (referenceCount >= srcAndRefPositions.length) { + int[] a = new int[srcAndRefPositions.length + 6]; + System.arraycopy(srcAndRefPositions, 0, a, 0, + srcAndRefPositions.length); + srcAndRefPositions = a; + } + srcAndRefPositions[referenceCount++] = sourcePosition; + srcAndRefPositions[referenceCount++] = referencePosition; + } + + /** + * Resolves all forward references to this label. This method must be called + * when this label is added to the bytecode of the method, i.e. when its + * position becomes known. This method fills in the blanks that where left + * in the bytecode by each forward reference previously added to this label. + * + * @param owner + * the code writer that calls this method. + * @param position + * the position of this label in the bytecode. + * @param data + * the bytecode of the method. + * @return <tt>true</tt> if a blank that was left for this label was to + * small to store the offset. In such a case the corresponding jump + * instruction is replaced with a pseudo instruction (using unused + * opcodes) using an unsigned two bytes offset. These pseudo + * instructions will need to be replaced with true instructions with + * wider offsets (4 bytes instead of 2). This is done in + * {@link MethodWriter#resizeInstructions}. + * @throws IllegalArgumentException + * if this label has already been resolved, or if it has not + * been created by the given code writer. + */ + boolean resolve(final MethodWriter owner, final int position, + final byte[] data) { + boolean needUpdate = false; + this.status |= RESOLVED; + this.position = position; + int i = 0; + while (i < referenceCount) { + int source = srcAndRefPositions[i++]; + int reference = srcAndRefPositions[i++]; + int offset; + if (source >= 0) { + offset = position - source; + if (offset < Short.MIN_VALUE || offset > Short.MAX_VALUE) { + /* + * changes the opcode of the jump instruction, in order to + * be able to find it later (see resizeInstructions in + * MethodWriter). These temporary opcodes are similar to + * jump instruction opcodes, except that the 2 bytes offset + * is unsigned (and can therefore represent values from 0 to + * 65535, which is sufficient since the size of a method is + * limited to 65535 bytes). + */ + int opcode = data[reference - 1] & 0xFF; + if (opcode <= Opcodes.JSR) { + // changes IFEQ ... JSR to opcodes 202 to 217 + data[reference - 1] = (byte) (opcode + 49); + } else { + // changes IFNULL and IFNONNULL to opcodes 218 and 219 + data[reference - 1] = (byte) (opcode + 20); + } + needUpdate = true; + } + data[reference++] = (byte) (offset >>> 8); + data[reference] = (byte) offset; + } else { + offset = position + source + 1; + data[reference++] = (byte) (offset >>> 24); + data[reference++] = (byte) (offset >>> 16); + data[reference++] = (byte) (offset >>> 8); + data[reference] = (byte) offset; + } + } + return needUpdate; + } + + /** + * Returns the first label of the series to which this label belongs. For an + * isolated label or for the first label in a series of successive labels, + * this method returns the label itself. For other labels it returns the + * first label of the series. + * + * @return the first label of the series to which this label belongs. + */ + Label getFirst() { + return !ClassReader.FRAMES || frame == null ? this : frame.owner; + } + + // ------------------------------------------------------------------------ + // Methods related to subroutines + // ------------------------------------------------------------------------ + + /** + * Returns true is this basic block belongs to the given subroutine. + * + * @param id + * a subroutine id. + * @return true is this basic block belongs to the given subroutine. + */ + boolean inSubroutine(final long id) { + if ((status & Label.VISITED) != 0) { + return (srcAndRefPositions[(int) (id >>> 32)] & (int) id) != 0; + } + return false; + } + + /** + * Returns true if this basic block and the given one belong to a common + * subroutine. + * + * @param block + * another basic block. + * @return true if this basic block and the given one belong to a common + * subroutine. + */ + boolean inSameSubroutine(final Label block) { + if ((status & VISITED) == 0 || (block.status & VISITED) == 0) { + return false; + } + for (int i = 0; i < srcAndRefPositions.length; ++i) { + if ((srcAndRefPositions[i] & block.srcAndRefPositions[i]) != 0) { + return true; + } + } + return false; + } + + /** + * Marks this basic block as belonging to the given subroutine. + * + * @param id + * a subroutine id. + * @param nbSubroutines + * the total number of subroutines in the method. + */ + void addToSubroutine(final long id, final int nbSubroutines) { + if ((status & VISITED) == 0) { + status |= VISITED; + srcAndRefPositions = new int[(nbSubroutines - 1) / 32 + 1]; + } + srcAndRefPositions[(int) (id >>> 32)] |= (int) id; + } + + /** + * Finds the basic blocks that belong to a given subroutine, and marks these + * blocks as belonging to this subroutine. This method follows the control + * flow graph to find all the blocks that are reachable from the current + * block WITHOUT following any JSR target. + * + * @param JSR + * a JSR block that jumps to this subroutine. If this JSR is not + * null it is added to the successor of the RET blocks found in + * the subroutine. + * @param id + * the id of this subroutine. + * @param nbSubroutines + * the total number of subroutines in the method. + */ + void visitSubroutine(final Label JSR, final long id, final int nbSubroutines) { + // user managed stack of labels, to avoid using a recursive method + // (recursivity can lead to stack overflow with very large methods) + Label stack = this; + while (stack != null) { + // removes a label l from the stack + Label l = stack; + stack = l.next; + l.next = null; + + if (JSR != null) { + if ((l.status & VISITED2) != 0) { + continue; + } + l.status |= VISITED2; + // adds JSR to the successors of l, if it is a RET block + if ((l.status & RET) != 0) { + if (!l.inSameSubroutine(JSR)) { + Edge e = new Edge(); + e.info = l.inputStackTop; + e.successor = JSR.successors.successor; + e.next = l.successors; + l.successors = e; + } + } + } else { + // if the l block already belongs to subroutine 'id', continue + if (l.inSubroutine(id)) { + continue; + } + // marks the l block as belonging to subroutine 'id' + l.addToSubroutine(id, nbSubroutines); + } + // pushes each successor of l on the stack, except JSR targets + Edge e = l.successors; + while (e != null) { + // if the l block is a JSR block, then 'l.successors.next' leads + // to the JSR target (see {@link #visitJumpInsn}) and must + // therefore not be followed + if ((l.status & Label.JSR) == 0 || e != l.successors.next) { + // pushes e.successor on the stack if it not already added + if (e.successor.next == null) { + e.successor.next = stack; + stack = e.successor; + } + } + e = e.next; + } + } + } + + // ------------------------------------------------------------------------ + // Overriden Object methods + // ------------------------------------------------------------------------ + + /** + * Returns a string representation of this label. + * + * @return a string representation of this label. + */ + @Override + public String toString() { + return "L" + System.identityHashCode(this); + } +}
http://git-wip-us.apache.org/repos/asf/tajo/blob/7603a3d4/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodVisitor.java ---------------------------------------------------------------------- diff --git a/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodVisitor.java b/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodVisitor.java new file mode 100644 index 0000000..1d6758e --- /dev/null +++ b/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodVisitor.java @@ -0,0 +1,662 @@ +/*** + * 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.apache.tajo.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> + * 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> + * <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> + * <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> + * </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 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(); + } + } +}
