langtools/src/share/classes/com/sun/tools/javap/CodeWriter.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */

 package com.sun.tools.javap;

 import java.util.ArrayList;
 import java.util.List;

 import com.sun.tools.classfile.AccessFlags;
 import com.sun.tools.classfile.Code_attribute;
 import com.sun.tools.classfile.ConstantPool;
 import com.sun.tools.classfile.ConstantPoolException;
 import com.sun.tools.classfile.DescriptorException;
 import com.sun.tools.classfile.Instruction;
 import com.sun.tools.classfile.Instruction.TypeKind;
 import com.sun.tools.classfile.Method;

 /*
  *  Write the contents of a Code attribute.
  *
  *  <p><b>This is NOT part of any supported API.
  *  If you write code that depends on this, you do so at your own risk.
  *  This code and its internal interfaces are subject to change or
  *  deletion without notice.</b>
  */
 public class CodeWriter extends BasicWriter {
     public static CodeWriter instance(Context context) {
         CodeWriter instance = context.get(CodeWriter.class);
         if (instance == null)
             instance = new CodeWriter(context);
         return instance;
     }

     protected CodeWriter(Context context) {
         super(context);
         context.put(CodeWriter.class, this);
         attrWriter = AttributeWriter.instance(context);
         classWriter = ClassWriter.instance(context);
         constantWriter = ConstantWriter.instance(context);
         sourceWriter = SourceWriter.instance(context);
         tryBlockWriter = TryBlockWriter.instance(context);
         stackMapWriter = StackMapWriter.instance(context);
         localVariableTableWriter = LocalVariableTableWriter.instance(context);
         localVariableTypeTableWriter = LocalVariableTypeTableWriter.instance(context);
         typeAnnotationWriter = TypeAnnotationWriter.instance(context);
         options = Options.instance(context);
     }

     void write(Code_attribute attr, ConstantPool constant_pool) {
         println("Code:");
         indent(+1);
         writeVerboseHeader(attr, constant_pool);
         writeInstrs(attr);
         writeExceptionTable(attr);
         attrWriter.write(attr, attr.attributes, constant_pool);
         indent(-1);
     }

     public void writeVerboseHeader(Code_attribute attr, ConstantPool constant_pool) {
         Method method = classWriter.getMethod();
         String argCount;
         try {
             int n = method.descriptor.getParameterCount(constant_pool);
             if (!method.access_flags.is(AccessFlags.ACC_STATIC))
                 ++n;  // for 'this'
             argCount = Integer.toString(n);
         } catch (ConstantPoolException e) {
             argCount = report(e);
         } catch (DescriptorException e) {
             argCount = report(e);
         }

         println("stack=" + attr.max_stack +
                 ", locals=" + attr.max_locals +
                 ", args_size=" + argCount);

     }

     public void writeInstrs(Code_attribute attr) {
         List<InstructionDetailWriter> detailWriters = getDetailWriters(attr);

         for (Instruction instr: attr.getInstructions()) {
             try {
                 for (InstructionDetailWriter w: detailWriters)
                     w.writeDetails(instr);
                 writeInstr(instr);
             } catch (ArrayIndexOutOfBoundsException e) {
                 println(report("error at or after byte " + instr.getPC()));
                 break;
             }
         }

         for (InstructionDetailWriter w: detailWriters)
             w.flush();
     }

     public void writeInstr(Instruction instr) {
         print(String.format("%4d: %-13s ", instr.getPC(), instr.getMnemonic()));
         // compute the number of indentations for the body of multi-line instructions
         // This is 6 (the width of "%4d: "), divided by the width of each indentation level,
         // and rounded up to the next integer.
         int indentWidth = options.indentWidth;
         int indent = (6 + indentWidth - 1) / indentWidth;
         instr.accept(instructionPrinter, indent);
         println();
     }
     // where
     Instruction.KindVisitor<Void,Integer> instructionPrinter =
             new Instruction.KindVisitor<Void,Integer>() {

         public Void visitNoOperands(Instruction instr, Integer indent) {
             return null;
         }

         public Void visitArrayType(Instruction instr, TypeKind kind, Integer indent) {
             print(" " + kind.name);
             return null;
         }

         public Void visitBranch(Instruction instr, int offset, Integer indent) {
             print((instr.getPC() + offset));
             return null;
         }

         public Void visitConstantPoolRef(Instruction instr, int index, Integer indent) {
             print("#" + index);
             tab();
             print("// ");
             printConstant(index);
             return null;
         }

         public Void visitConstantPoolRefAndValue(Instruction instr, int index, int value, Integer indent) {
             print("#" + index + ",  " + value);
             tab();
             print("// ");
             printConstant(index);
             return null;
         }

         public Void visitLocal(Instruction instr, int index, Integer indent) {
             print(index);
             return null;
         }

         public Void visitLocalAndValue(Instruction instr, int index, int value, Integer indent) {
             print(index + ", " + value);
             return null;
         }

         public Void visitLookupSwitch(Instruction instr,
                 int default_, int npairs, int[] matches, int[] offsets, Integer indent) {
             int pc = instr.getPC();
             print("{ // " + npairs);
             indent(indent);
             for (int i = 0; i < npairs; i++) {
                 print(String.format("%n%12d: %d", matches[i], (pc + offsets[i])));
             }
             print("\n     default: " + (pc + default_) + "\n}");
             indent(-indent);
             return null;
         }

         public Void visitTableSwitch(Instruction instr,
                 int default_, int low, int high, int[] offsets, Integer indent) {
             int pc = instr.getPC();
             print("{ // " + low + " to " + high);
             indent(indent);
             for (int i = 0; i < offsets.length; i++) {
                 print(String.format("%n%12d: %d", (low + i), (pc + offsets[i])));
             }
             print("\n     default: " + (pc + default_) + "\n}");
             indent(-indent);
             return null;
         }

         public Void visitValue(Instruction instr, int value, Integer indent) {
             print(value);
             return null;
         }

         public Void visitUnknown(Instruction instr, Integer indent) {
             return null;
         }
     };


     public void writeExceptionTable(Code_attribute attr) {
         if (attr.exception_table_length > 0) {
             println("Exception table:");
             indent(+1);
             println(" from    to  target type");
             for (int i = 0; i < attr.exception_table.length; i++) {
                 Code_attribute.Exception_data handler = attr.exception_table[i];
                 print(String.format(" %5d %5d %5d",
                         handler.start_pc, handler.end_pc, handler.handler_pc));
                 print("   ");
                 int catch_type = handler.catch_type;
                 if (catch_type == 0) {
                     println("any");
                 } else {
                     print("Class ");
                     println(constantWriter.stringValue(catch_type));
                 }
             }
             indent(-1);
         }

     }

     private void printConstant(int index) {
         constantWriter.write(index);
     }

     private List<InstructionDetailWriter> getDetailWriters(Code_attribute attr) {
         List<InstructionDetailWriter> detailWriters = new ArrayList<>();
         if (options.details.contains(InstructionDetailWriter.Kind.SOURCE)) {
             sourceWriter.reset(classWriter.getClassFile(), attr);
             if (sourceWriter.hasSource())
                 detailWriters.add(sourceWriter);
             else
                 println("(Source code not available)");
         }

         if (options.details.contains(InstructionDetailWriter.Kind.LOCAL_VARS)) {
             localVariableTableWriter.reset(attr);
             detailWriters.add(localVariableTableWriter);
         }

         if (options.details.contains(InstructionDetailWriter.Kind.LOCAL_VAR_TYPES)) {
             localVariableTypeTableWriter.reset(attr);
             detailWriters.add(localVariableTypeTableWriter);
         }

         if (options.details.contains(InstructionDetailWriter.Kind.STACKMAPS)) {
             stackMapWriter.reset(attr);
             stackMapWriter.writeInitialDetails();
             detailWriters.add(stackMapWriter);
         }

         if (options.details.contains(InstructionDetailWriter.Kind.TRY_BLOCKS)) {
             tryBlockWriter.reset(attr);
             detailWriters.add(tryBlockWriter);
         }

         if (options.details.contains(InstructionDetailWriter.Kind.TYPE_ANNOS)) {
             typeAnnotationWriter.reset(attr);
             detailWriters.add(typeAnnotationWriter);
         }

         return detailWriters;
     }

     private AttributeWriter attrWriter;
     private ClassWriter classWriter;
     private ConstantWriter constantWriter;
     private LocalVariableTableWriter localVariableTableWriter;
     private LocalVariableTypeTableWriter localVariableTypeTableWriter;
     private TypeAnnotationWriter typeAnnotationWriter;
     private SourceWriter sourceWriter;
     private StackMapWriter stackMapWriter;
     private TryBlockWriter tryBlockWriter;
     private Options options;
 }
	/*
	* Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package com.sun.tools.javap;

	import java.util.ArrayList;
	import java.util.List;

	import com.sun.tools.classfile.AccessFlags;
	import com.sun.tools.classfile.Code_attribute;
	import com.sun.tools.classfile.ConstantPool;
	import com.sun.tools.classfile.ConstantPoolException;
	import com.sun.tools.classfile.DescriptorException;
	import com.sun.tools.classfile.Instruction;
	import com.sun.tools.classfile.Instruction.TypeKind;
	import com.sun.tools.classfile.Method;

	/*
	* Write the contents of a Code attribute.
	*
	* <p><b>This is NOT part of any supported API.
	* If you write code that depends on this, you do so at your own risk.
	* This code and its internal interfaces are subject to change or
	* deletion without notice.</b>
	*/
	public class CodeWriter extends BasicWriter {
	public static CodeWriter instance(Context context) {
	CodeWriter instance = context.get(CodeWriter.class);
	if (instance == null)
	instance = new CodeWriter(context);
	return instance;
	}

	protected CodeWriter(Context context) {
	super(context);
	context.put(CodeWriter.class, this);
	attrWriter = AttributeWriter.instance(context);
	classWriter = ClassWriter.instance(context);
	constantWriter = ConstantWriter.instance(context);
	sourceWriter = SourceWriter.instance(context);
	tryBlockWriter = TryBlockWriter.instance(context);
	stackMapWriter = StackMapWriter.instance(context);
	localVariableTableWriter = LocalVariableTableWriter.instance(context);
	localVariableTypeTableWriter = LocalVariableTypeTableWriter.instance(context);
	typeAnnotationWriter = TypeAnnotationWriter.instance(context);
	options = Options.instance(context);
	}

	void write(Code_attribute attr, ConstantPool constant_pool) {
	println("Code:");
	indent(+1);
	writeVerboseHeader(attr, constant_pool);
	writeInstrs(attr);
	writeExceptionTable(attr);
	attrWriter.write(attr, attr.attributes, constant_pool);
	indent(-1);
	}

	public void writeVerboseHeader(Code_attribute attr, ConstantPool constant_pool) {
	Method method = classWriter.getMethod();
	String argCount;
	try {
	int n = method.descriptor.getParameterCount(constant_pool);
	if (!method.access_flags.is(AccessFlags.ACC_STATIC))
	++n; // for 'this'
	argCount = Integer.toString(n);
	} catch (ConstantPoolException e) {
	argCount = report(e);
	} catch (DescriptorException e) {
	argCount = report(e);
	}

	println("stack=" + attr.max_stack +
	", locals=" + attr.max_locals +
	", args_size=" + argCount);

	}

	public void writeInstrs(Code_attribute attr) {
	List<InstructionDetailWriter> detailWriters = getDetailWriters(attr);

	for (Instruction instr: attr.getInstructions()) {
	try {
	for (InstructionDetailWriter w: detailWriters)
	w.writeDetails(instr);
	writeInstr(instr);
	} catch (ArrayIndexOutOfBoundsException e) {
	println(report("error at or after byte " + instr.getPC()));
	break;
	}
	}

	for (InstructionDetailWriter w: detailWriters)
	w.flush();
	}

	public void writeInstr(Instruction instr) {
	print(String.format("%4d: %-13s ", instr.getPC(), instr.getMnemonic()));
	// compute the number of indentations for the body of multi-line instructions
	// This is 6 (the width of "%4d: "), divided by the width of each indentation level,
	// and rounded up to the next integer.
	int indentWidth = options.indentWidth;
	int indent = (6 + indentWidth - 1) / indentWidth;
	instr.accept(instructionPrinter, indent);
	println();
	}
	// where
	Instruction.KindVisitor<Void,Integer> instructionPrinter =
	new Instruction.KindVisitor<Void,Integer>() {

	public Void visitNoOperands(Instruction instr, Integer indent) {
	return null;
	}

	public Void visitArrayType(Instruction instr, TypeKind kind, Integer indent) {
	print(" " + kind.name);
	return null;
	}

	public Void visitBranch(Instruction instr, int offset, Integer indent) {
	print((instr.getPC() + offset));
	return null;
	}

	public Void visitConstantPoolRef(Instruction instr, int index, Integer indent) {
	print("#" + index);
	tab();
	print("// ");
	printConstant(index);
	return null;
	}

	public Void visitConstantPoolRefAndValue(Instruction instr, int index, int value, Integer indent) {
	print("#" + index + ", " + value);
	tab();
	print("// ");
	printConstant(index);
	return null;
	}

	public Void visitLocal(Instruction instr, int index, Integer indent) {
	print(index);
	return null;
	}

	public Void visitLocalAndValue(Instruction instr, int index, int value, Integer indent) {
	print(index + ", " + value);
	return null;
	}

	public Void visitLookupSwitch(Instruction instr,
	int default_, int npairs, int[] matches, int[] offsets, Integer indent) {
	int pc = instr.getPC();
	print("{ // " + npairs);
	indent(indent);
	for (int i = 0; i < npairs; i++) {
	print(String.format("%n%12d: %d", matches[i], (pc + offsets[i])));
	}
	print("\n default: " + (pc + default_) + "\n}");
	indent(-indent);
	return null;
	}

	public Void visitTableSwitch(Instruction instr,
	int default_, int low, int high, int[] offsets, Integer indent) {
	int pc = instr.getPC();
	print("{ // " + low + " to " + high);
	indent(indent);
	for (int i = 0; i < offsets.length; i++) {
	print(String.format("%n%12d: %d", (low + i), (pc + offsets[i])));
	}
	print("\n default: " + (pc + default_) + "\n}");
	indent(-indent);
	return null;
	}

	public Void visitValue(Instruction instr, int value, Integer indent) {
	print(value);
	return null;
	}

	public Void visitUnknown(Instruction instr, Integer indent) {
	return null;
	}
	};


	public void writeExceptionTable(Code_attribute attr) {
	if (attr.exception_table_length > 0) {
	println("Exception table:");
	indent(+1);
	println(" from to target type");
	for (int i = 0; i < attr.exception_table.length; i++) {
	Code_attribute.Exception_data handler = attr.exception_table[i];
	print(String.format(" %5d %5d %5d",
	handler.start_pc, handler.end_pc, handler.handler_pc));
	print(" ");
	int catch_type = handler.catch_type;
	if (catch_type == 0) {
	println("any");
	} else {
	print("Class ");
	println(constantWriter.stringValue(catch_type));
	}
	}
	indent(-1);
	}

	}

	private void printConstant(int index) {
	constantWriter.write(index);
	}

	private List<InstructionDetailWriter> getDetailWriters(Code_attribute attr) {
	List<InstructionDetailWriter> detailWriters = new ArrayList<>();
	if (options.details.contains(InstructionDetailWriter.Kind.SOURCE)) {
	sourceWriter.reset(classWriter.getClassFile(), attr);
	if (sourceWriter.hasSource())
	detailWriters.add(sourceWriter);
	else
	println("(Source code not available)");
	}

	if (options.details.contains(InstructionDetailWriter.Kind.LOCAL_VARS)) {
	localVariableTableWriter.reset(attr);
	detailWriters.add(localVariableTableWriter);
	}

	if (options.details.contains(InstructionDetailWriter.Kind.LOCAL_VAR_TYPES)) {
	localVariableTypeTableWriter.reset(attr);
	detailWriters.add(localVariableTypeTableWriter);
	}

	if (options.details.contains(InstructionDetailWriter.Kind.STACKMAPS)) {
	stackMapWriter.reset(attr);
	stackMapWriter.writeInitialDetails();
	detailWriters.add(stackMapWriter);
	}

	if (options.details.contains(InstructionDetailWriter.Kind.TRY_BLOCKS)) {
	tryBlockWriter.reset(attr);
	detailWriters.add(tryBlockWriter);
	}

	if (options.details.contains(InstructionDetailWriter.Kind.TYPE_ANNOS)) {
	typeAnnotationWriter.reset(attr);
	detailWriters.add(typeAnnotationWriter);
	}

	return detailWriters;
	}

	private AttributeWriter attrWriter;
	private ClassWriter classWriter;
	private ConstantWriter constantWriter;
	private LocalVariableTableWriter localVariableTableWriter;
	private LocalVariableTypeTableWriter localVariableTypeTableWriter;
	private TypeAnnotationWriter typeAnnotationWriter;
	private SourceWriter sourceWriter;
	private StackMapWriter stackMapWriter;
	private TryBlockWriter tryBlockWriter;
	private Options options;
	}