CodeHTML.java
- /*
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- package org.apache.bcel.util;
- import java.io.IOException;
- import java.io.PrintWriter;
- import java.nio.charset.Charset;
- import java.util.BitSet;
- import org.apache.bcel.Const;
- import org.apache.bcel.classfile.Attribute;
- import org.apache.bcel.classfile.Code;
- import org.apache.bcel.classfile.CodeException;
- import org.apache.bcel.classfile.ConstantFieldref;
- import org.apache.bcel.classfile.ConstantInterfaceMethodref;
- import org.apache.bcel.classfile.ConstantInvokeDynamic;
- import org.apache.bcel.classfile.ConstantMethodref;
- import org.apache.bcel.classfile.ConstantNameAndType;
- import org.apache.bcel.classfile.ConstantPool;
- import org.apache.bcel.classfile.LocalVariableTable;
- import org.apache.bcel.classfile.Method;
- import org.apache.bcel.classfile.Utility;
- /**
- * Convert code into HTML file.
- */
- final class CodeHTML {
- private static boolean wide;
- private final String className; // name of current class
- // private Method[] methods; // Methods to print
- private final PrintWriter printWriter; // file to write to
- private BitSet gotoSet;
- private final ConstantPool constantPool;
- private final ConstantHTML constantHtml;
- CodeHTML(final String dir, final String className, final Method[] methods, final ConstantPool constantPool, final ConstantHTML constantHtml,
- final Charset charset) throws IOException {
- this.className = className;
- // this.methods = methods;
- this.constantPool = constantPool;
- this.constantHtml = constantHtml;
- try (PrintWriter newPrintWriter = new PrintWriter(dir + className + "_code.html", charset.name())) {
- printWriter = newPrintWriter;
- printWriter.print("<HTML><head><meta charset=\"");
- printWriter.print(charset.name());
- printWriter.println("\"></head>");
- printWriter.println("<BODY BGCOLOR=\"#C0C0C0\">");
- for (int i = 0; i < methods.length; i++) {
- writeMethod(methods[i], i);
- }
- printWriter.println("</BODY></HTML>");
- }
- }
- /**
- * Disassemble a stream of byte codes and return the string representation.
- *
- * @param stream data input stream
- * @return String representation of byte code
- */
- private String codeToHTML(final ByteSequence bytes, final int methodNumber) throws IOException {
- final short opcode = (short) bytes.readUnsignedByte();
- String name;
- String signature;
- int defaultOffset = 0;
- int low;
- int high;
- int index;
- int classIndex;
- int vindex;
- int constant;
- int[] jumpTable;
- int noPadBytes = 0;
- int offset;
- final StringBuilder buf = new StringBuilder(256); // CHECKSTYLE IGNORE MagicNumber
- buf.append("<TT>").append(Const.getOpcodeName(opcode)).append("</TT></TD><TD>");
- /*
- * Special case: Skip (0-3) padding bytes, i.e., the following bytes are 4-byte-aligned
- */
- if (opcode == Const.TABLESWITCH || opcode == Const.LOOKUPSWITCH) {
- final int remainder = bytes.getIndex() % 4;
- noPadBytes = remainder == 0 ? 0 : 4 - remainder;
- for (int i = 0; i < noPadBytes; i++) {
- bytes.readByte();
- }
- // Both cases have a field default_offset in common
- defaultOffset = bytes.readInt();
- }
- switch (opcode) {
- case Const.TABLESWITCH:
- low = bytes.readInt();
- high = bytes.readInt();
- offset = bytes.getIndex() - 12 - noPadBytes - 1;
- defaultOffset += offset;
- buf.append("<TABLE BORDER=1><TR>");
- // Print switch indices in first row (and default)
- jumpTable = new int[high - low + 1];
- for (int i = 0; i < jumpTable.length; i++) {
- jumpTable[i] = offset + bytes.readInt();
- buf.append("<TH>").append(low + i).append("</TH>");
- }
- buf.append("<TH>default</TH></TR>\n<TR>");
- // Print target and default indices in second row
- for (final int element : jumpTable) {
- buf.append("<TD><A HREF=\"#code").append(methodNumber).append("@").append(element).append("\">").append(element).append("</A></TD>");
- }
- buf.append("<TD><A HREF=\"#code").append(methodNumber).append("@").append(defaultOffset).append("\">").append(defaultOffset)
- .append("</A></TD></TR>\n</TABLE>\n");
- break;
- /*
- * Lookup switch has variable length arguments.
- */
- case Const.LOOKUPSWITCH:
- final int npairs = bytes.readInt();
- offset = bytes.getIndex() - 8 - noPadBytes - 1;
- jumpTable = new int[npairs];
- defaultOffset += offset;
- buf.append("<TABLE BORDER=1><TR>");
- // Print switch indices in first row (and default)
- for (int i = 0; i < npairs; i++) {
- final int match = bytes.readInt();
- jumpTable[i] = offset + bytes.readInt();
- buf.append("<TH>").append(match).append("</TH>");
- }
- buf.append("<TH>default</TH></TR>\n<TR>");
- // Print target and default indices in second row
- for (int i = 0; i < npairs; i++) {
- buf.append("<TD><A HREF=\"#code").append(methodNumber).append("@").append(jumpTable[i]).append("\">").append(jumpTable[i])
- .append("</A></TD>");
- }
- buf.append("<TD><A HREF=\"#code").append(methodNumber).append("@").append(defaultOffset).append("\">").append(defaultOffset)
- .append("</A></TD></TR>\n</TABLE>\n");
- break;
- /*
- * Two address bytes + offset from start of byte stream form the jump target.
- */
- case Const.GOTO:
- case Const.IFEQ:
- case Const.IFGE:
- case Const.IFGT:
- case Const.IFLE:
- case Const.IFLT:
- case Const.IFNE:
- case Const.IFNONNULL:
- case Const.IFNULL:
- case Const.IF_ACMPEQ:
- case Const.IF_ACMPNE:
- case Const.IF_ICMPEQ:
- case Const.IF_ICMPGE:
- case Const.IF_ICMPGT:
- case Const.IF_ICMPLE:
- case Const.IF_ICMPLT:
- case Const.IF_ICMPNE:
- case Const.JSR:
- index = bytes.getIndex() + bytes.readShort() - 1;
- buf.append("<A HREF=\"#code").append(methodNumber).append("@").append(index).append("\">").append(index).append("</A>");
- break;
- /*
- * Same for 32-bit wide jumps
- */
- case Const.GOTO_W:
- case Const.JSR_W:
- final int windex = bytes.getIndex() + bytes.readInt() - 1;
- buf.append("<A HREF=\"#code").append(methodNumber).append("@").append(windex).append("\">").append(windex).append("</A>");
- break;
- /*
- * Index byte references local variable (register)
- */
- case Const.ALOAD:
- case Const.ASTORE:
- case Const.DLOAD:
- case Const.DSTORE:
- case Const.FLOAD:
- case Const.FSTORE:
- case Const.ILOAD:
- case Const.ISTORE:
- case Const.LLOAD:
- case Const.LSTORE:
- case Const.RET:
- if (wide) {
- vindex = bytes.readShort();
- wide = false; // Clear flag
- } else {
- vindex = bytes.readUnsignedByte();
- }
- buf.append("%").append(vindex);
- break;
- /*
- * Remember wide byte which is used to form a 16-bit address in the following instruction. Relies on that the method is
- * called again with the following opcode.
- */
- case Const.WIDE:
- wide = true;
- buf.append("(wide)");
- break;
- /*
- * Array of basic type.
- */
- case Const.NEWARRAY:
- buf.append("<FONT COLOR=\"#00FF00\">").append(Const.getTypeName(bytes.readByte())).append("</FONT>");
- break;
- /*
- * Access object/class fields.
- */
- case Const.GETFIELD:
- case Const.GETSTATIC:
- case Const.PUTFIELD:
- case Const.PUTSTATIC:
- index = bytes.readShort();
- final ConstantFieldref c1 = constantPool.getConstant(index, Const.CONSTANT_Fieldref, ConstantFieldref.class);
- classIndex = c1.getClassIndex();
- name = constantPool.getConstantString(classIndex, Const.CONSTANT_Class);
- name = Utility.compactClassName(name, false);
- index = c1.getNameAndTypeIndex();
- final String fieldName = constantPool.constantToString(index, Const.CONSTANT_NameAndType);
- if (name.equals(className)) { // Local field
- buf.append("<A HREF=\"").append(className).append("_methods.html#field").append(fieldName).append("\" TARGET=Methods>").append(fieldName)
- .append("</A>\n");
- } else {
- buf.append(constantHtml.referenceConstant(classIndex)).append(".").append(fieldName);
- }
- break;
- /*
- * Operands are references to classes in constant pool
- */
- case Const.CHECKCAST:
- case Const.INSTANCEOF:
- case Const.NEW:
- index = bytes.readShort();
- buf.append(constantHtml.referenceConstant(index));
- break;
- /*
- * Operands are references to methods in constant pool
- */
- case Const.INVOKESPECIAL:
- case Const.INVOKESTATIC:
- case Const.INVOKEVIRTUAL:
- case Const.INVOKEINTERFACE:
- case Const.INVOKEDYNAMIC:
- final int mIndex = bytes.readShort();
- String str;
- if (opcode == Const.INVOKEINTERFACE) { // Special treatment needed
- bytes.readUnsignedByte(); // Redundant
- bytes.readUnsignedByte(); // Reserved
- // int nargs = bytes.readUnsignedByte(); // Redundant
- // int reserved = bytes.readUnsignedByte(); // Reserved
- final ConstantInterfaceMethodref c = constantPool.getConstant(mIndex, Const.CONSTANT_InterfaceMethodref, ConstantInterfaceMethodref.class);
- classIndex = c.getClassIndex();
- index = c.getNameAndTypeIndex();
- name = Class2HTML.referenceClass(classIndex);
- } else if (opcode == Const.INVOKEDYNAMIC) { // Special treatment needed
- bytes.readUnsignedByte(); // Reserved
- bytes.readUnsignedByte(); // Reserved
- final ConstantInvokeDynamic c = constantPool.getConstant(mIndex, Const.CONSTANT_InvokeDynamic, ConstantInvokeDynamic.class);
- index = c.getNameAndTypeIndex();
- name = "#" + c.getBootstrapMethodAttrIndex();
- } else {
- // UNDONE: Java8 now allows INVOKESPECIAL and INVOKESTATIC to
- // reference EITHER a Methodref OR an InterfaceMethodref.
- // Not sure if that affects this code or not. (markro)
- final ConstantMethodref c = constantPool.getConstant(mIndex, Const.CONSTANT_Methodref, ConstantMethodref.class);
- classIndex = c.getClassIndex();
- index = c.getNameAndTypeIndex();
- name = Class2HTML.referenceClass(classIndex);
- }
- str = Class2HTML.toHTML(constantPool.constantToString(constantPool.getConstant(index, Const.CONSTANT_NameAndType)));
- // Get signature, i.e., types
- final ConstantNameAndType c2 = constantPool.getConstant(index, Const.CONSTANT_NameAndType, ConstantNameAndType.class);
- signature = constantPool.constantToString(c2.getSignatureIndex(), Const.CONSTANT_Utf8);
- final String[] args = Utility.methodSignatureArgumentTypes(signature, false);
- final String type = Utility.methodSignatureReturnType(signature, false);
- buf.append(name).append(".<A HREF=\"").append(className).append("_cp.html#cp").append(mIndex).append("\" TARGET=ConstantPool>").append(str)
- .append("</A>").append("(");
- // List arguments
- for (int i = 0; i < args.length; i++) {
- buf.append(Class2HTML.referenceType(args[i]));
- if (i < args.length - 1) {
- buf.append(", ");
- }
- }
- // Attach return type
- buf.append("):").append(Class2HTML.referenceType(type));
- break;
- /*
- * Operands are references to items in constant pool
- */
- case Const.LDC_W:
- case Const.LDC2_W:
- index = bytes.readShort();
- buf.append("<A HREF=\"").append(className).append("_cp.html#cp").append(index).append("\" TARGET=\"ConstantPool\">")
- .append(Class2HTML.toHTML(constantPool.constantToString(index, constantPool.getConstant(index).getTag()))).append("</a>");
- break;
- case Const.LDC:
- index = bytes.readUnsignedByte();
- buf.append("<A HREF=\"").append(className).append("_cp.html#cp").append(index).append("\" TARGET=\"ConstantPool\">")
- .append(Class2HTML.toHTML(constantPool.constantToString(index, constantPool.getConstant(index).getTag()))).append("</a>");
- break;
- /*
- * Array of references.
- */
- case Const.ANEWARRAY:
- index = bytes.readShort();
- buf.append(constantHtml.referenceConstant(index));
- break;
- /*
- * Multidimensional array of references.
- */
- case Const.MULTIANEWARRAY:
- index = bytes.readShort();
- final int dimensions = bytes.readByte();
- buf.append(constantHtml.referenceConstant(index)).append(":").append(dimensions).append("-dimensional");
- break;
- /*
- * Increment local variable.
- */
- case Const.IINC:
- if (wide) {
- vindex = bytes.readShort();
- constant = bytes.readShort();
- wide = false;
- } else {
- vindex = bytes.readUnsignedByte();
- constant = bytes.readByte();
- }
- buf.append("%").append(vindex).append(" ").append(constant);
- break;
- default:
- if (Const.getNoOfOperands(opcode) > 0) {
- for (int i = 0; i < Const.getOperandTypeCount(opcode); i++) {
- switch (Const.getOperandType(opcode, i)) {
- case Const.T_BYTE:
- buf.append(bytes.readUnsignedByte());
- break;
- case Const.T_SHORT: // Either branch or index
- buf.append(bytes.readShort());
- break;
- case Const.T_INT:
- buf.append(bytes.readInt());
- break;
- default: // Never reached
- throw new IllegalStateException("Unreachable default case reached! " + Const.getOperandType(opcode, i));
- }
- buf.append(" ");
- }
- }
- }
- buf.append("</TD>");
- return buf.toString();
- }
- /**
- * Find all target addresses in code, so that they can be marked with <A NAME = ...>. Target addresses are kept in
- * an BitSet object.
- */
- private void findGotos(final ByteSequence bytes, final Code code) throws IOException {
- int index;
- gotoSet = new BitSet(bytes.available());
- int opcode;
- /*
- * First get Code attribute from method and the exceptions handled (try .. catch) in this method. We only need the line
- * number here.
- */
- if (code != null) {
- final CodeException[] ce = code.getExceptionTable();
- for (final CodeException cex : ce) {
- gotoSet.set(cex.getStartPC());
- gotoSet.set(cex.getEndPC());
- gotoSet.set(cex.getHandlerPC());
- }
- // Look for local variables and their range
- final Attribute[] attributes = code.getAttributes();
- for (final Attribute attribute : attributes) {
- if (attribute.getTag() == Const.ATTR_LOCAL_VARIABLE_TABLE) {
- ((LocalVariableTable) attribute).forEach(var -> {
- final int start = var.getStartPC();
- gotoSet.set(start);
- gotoSet.set(start + var.getLength());
- });
- break;
- }
- }
- }
- // Get target addresses from GOTO, JSR, TABLESWITCH, etc.
- while (bytes.available() > 0) {
- opcode = bytes.readUnsignedByte();
- // System.out.println(getOpcodeName(opcode));
- switch (opcode) {
- case Const.TABLESWITCH:
- case Const.LOOKUPSWITCH:
- // bytes.readByte(); // Skip already read byte
- final int remainder = bytes.getIndex() % 4;
- final int noPadBytes = remainder == 0 ? 0 : 4 - remainder;
- int defaultOffset;
- int offset;
- for (int j = 0; j < noPadBytes; j++) {
- bytes.readByte();
- }
- // Both cases have a field default_offset in common
- defaultOffset = bytes.readInt();
- if (opcode == Const.TABLESWITCH) {
- final int low = bytes.readInt();
- final int high = bytes.readInt();
- offset = bytes.getIndex() - 12 - noPadBytes - 1;
- defaultOffset += offset;
- gotoSet.set(defaultOffset);
- for (int j = 0; j < high - low + 1; j++) {
- index = offset + bytes.readInt();
- gotoSet.set(index);
- }
- } else { // LOOKUPSWITCH
- final int npairs = bytes.readInt();
- offset = bytes.getIndex() - 8 - noPadBytes - 1;
- defaultOffset += offset;
- gotoSet.set(defaultOffset);
- for (int j = 0; j < npairs; j++) {
- // int match = bytes.readInt();
- bytes.readInt();
- index = offset + bytes.readInt();
- gotoSet.set(index);
- }
- }
- break;
- case Const.GOTO:
- case Const.IFEQ:
- case Const.IFGE:
- case Const.IFGT:
- case Const.IFLE:
- case Const.IFLT:
- case Const.IFNE:
- case Const.IFNONNULL:
- case Const.IFNULL:
- case Const.IF_ACMPEQ:
- case Const.IF_ACMPNE:
- case Const.IF_ICMPEQ:
- case Const.IF_ICMPGE:
- case Const.IF_ICMPGT:
- case Const.IF_ICMPLE:
- case Const.IF_ICMPLT:
- case Const.IF_ICMPNE:
- case Const.JSR:
- // bytes.readByte(); // Skip already read byte
- index = bytes.getIndex() + bytes.readShort() - 1;
- gotoSet.set(index);
- break;
- case Const.GOTO_W:
- case Const.JSR_W:
- // bytes.readByte(); // Skip already read byte
- index = bytes.getIndex() + bytes.readInt() - 1;
- gotoSet.set(index);
- break;
- default:
- bytes.unreadByte();
- codeToHTML(bytes, 0); // Ignore output
- }
- }
- }
- /**
- * Write a single method with the byte code associated with it.
- */
- private void writeMethod(final Method method, final int methodNumber) throws IOException {
- // Get raw signature
- final String signature = method.getSignature();
- // Get array of strings containing the argument types
- final String[] args = Utility.methodSignatureArgumentTypes(signature, false);
- // Get return type string
- final String type = Utility.methodSignatureReturnType(signature, false);
- // Get method name
- final String name = method.getName();
- final String htmlName = Class2HTML.toHTML(name);
- // Get method's access flags
- String access = Utility.accessToString(method.getAccessFlags());
- access = Utility.replace(access, " ", " ");
- // Get the method's attributes, the Code Attribute in particular
- final Attribute[] attributes = method.getAttributes();
- printWriter.print("<P><B><FONT COLOR=\"#FF0000\">" + access + "</FONT> " + "<A NAME=method" + methodNumber + ">" + Class2HTML.referenceType(type)
- + "</A> <A HREF=\"" + className + "_methods.html#method" + methodNumber + "\" TARGET=Methods>" + htmlName + "</A>(");
- for (int i = 0; i < args.length; i++) {
- printWriter.print(Class2HTML.referenceType(args[i]));
- if (i < args.length - 1) {
- printWriter.print(", ");
- }
- }
- printWriter.println(")</B></P>");
- Code c = null;
- byte[] code = null;
- if (attributes.length > 0) {
- printWriter.print("<H4>Attributes</H4><UL>\n");
- for (int i = 0; i < attributes.length; i++) {
- byte tag = attributes[i].getTag();
- if (tag != Const.ATTR_UNKNOWN) {
- printWriter.print("<LI><A HREF=\"" + className + "_attributes.html#method" + methodNumber + "@" + i + "\" TARGET=Attributes>"
- + Const.getAttributeName(tag) + "</A></LI>\n");
- } else {
- printWriter.print("<LI>" + attributes[i] + "</LI>");
- }
- if (tag == Const.ATTR_CODE) {
- c = (Code) attributes[i];
- final Attribute[] attributes2 = c.getAttributes();
- code = c.getCode();
- printWriter.print("<UL>");
- for (int j = 0; j < attributes2.length; j++) {
- tag = attributes2[j].getTag();
- printWriter.print("<LI><A HREF=\"" + className + "_attributes.html#" + "method" + methodNumber + "@" + i + "@" + j
- + "\" TARGET=Attributes>" + Const.getAttributeName(tag) + "</A></LI>\n");
- }
- printWriter.print("</UL>");
- }
- }
- printWriter.println("</UL>");
- }
- if (code != null) { // No code, an abstract method, e.g.
- // System.out.println(name + "\n" + Utility.codeToString(code, constantPool, 0, -1));
- // Print the byte code
- try (ByteSequence stream = new ByteSequence(code)) {
- stream.mark(stream.available());
- findGotos(stream, c);
- stream.reset();
- printWriter.println("<TABLE BORDER=0><TR><TH ALIGN=LEFT>Byte<BR>offset</TH>" + "<TH ALIGN=LEFT>Instruction</TH><TH ALIGN=LEFT>Argument</TH>");
- while (stream.available() > 0) {
- final int offset = stream.getIndex();
- final String str = codeToHTML(stream, methodNumber);
- String anchor = "";
- /*
- * Sets an anchor mark if this line is targetted by a goto, jsr, etc. Defining an anchor for every line is very
- * inefficient!
- */
- if (gotoSet.get(offset)) {
- anchor = "<A NAME=code" + methodNumber + "@" + offset + "></A>";
- }
- String anchor2;
- if (stream.getIndex() == code.length) {
- anchor2 = "<A NAME=code" + methodNumber + "@" + code.length + ">" + offset + "</A>";
- } else {
- anchor2 = "" + offset;
- }
- printWriter.println("<TR VALIGN=TOP><TD>" + anchor2 + "</TD><TD>" + anchor + str + "</TR>");
- }
- }
- // Mark last line, may be targetted from Attributes window
- printWriter.println("<TR><TD> </A></TD></TR>");
- printWriter.println("</TABLE>");
- }
- }
- }