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/*
 * Copyright (c) 2007, 2016, 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.net.URI;
import java.text.DateFormat;
import java.util.Collection;
import java.util.Date;
import java.util.List;

import com.sun.tools.classfile.AccessFlags;
import com.sun.tools.classfile.Attribute;
import com.sun.tools.classfile.Attributes;
import com.sun.tools.classfile.ClassFile;
import com.sun.tools.classfile.Code_attribute;
import com.sun.tools.classfile.ConstantPool;
import com.sun.tools.classfile.ConstantPoolException;
import com.sun.tools.classfile.ConstantValue_attribute;
import com.sun.tools.classfile.Descriptor;
import com.sun.tools.classfile.Descriptor.InvalidDescriptor;
import com.sun.tools.classfile.Exceptions_attribute;
import com.sun.tools.classfile.Field;
import com.sun.tools.classfile.Method;
import com.sun.tools.classfile.Module_attribute;
import com.sun.tools.classfile.Signature;
import com.sun.tools.classfile.Signature_attribute;
import com.sun.tools.classfile.SourceFile_attribute;
import com.sun.tools.classfile.Type;
import com.sun.tools.classfile.Type.ArrayType;
import com.sun.tools.classfile.Type.ClassSigType;
import com.sun.tools.classfile.Type.ClassType;
import com.sun.tools.classfile.Type.MethodType;
import com.sun.tools.classfile.Type.SimpleType;
import com.sun.tools.classfile.Type.TypeParamType;
import com.sun.tools.classfile.Type.WildcardType;

import static com.sun.tools.classfile.AccessFlags.*;
import static com.sun.tools.classfile.ConstantPool.CONSTANT_Module;
import static com.sun.tools.classfile.ConstantPool.CONSTANT_Package;

/*
 *  The main javap class to write the contents of a class file as text.
 *
 *  

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. */ public class ClassWriter extends BasicWriter { static ClassWriter instance(Context context) { ClassWriter instance = context.get(ClassWriter.class); if (instance == null) instance = new ClassWriter(context); return instance; } protected ClassWriter(Context context) { super(context); context.put(ClassWriter.class, this); options = Options.instance(context); attrWriter = AttributeWriter.instance(context); codeWriter = CodeWriter.instance(context); constantWriter = ConstantWriter.instance(context); } void setDigest(String name, byte[] digest) { this.digestName = name; this.digest = digest; } void setFile(URI uri) { this.uri = uri; } void setFileSize(int size) { this.size = size; } void setLastModified(long lastModified) { this.lastModified = lastModified; } protected ClassFile getClassFile() { return classFile; } protected void setClassFile(ClassFile cf) { classFile = cf; constant_pool = classFile.constant_pool; } protected Method getMethod() { return method; } protected void setMethod(Method m) { method = m; } public void write(ClassFile cf) { setClassFile(cf); if (options.sysInfo || options.verbose) { if (uri != null) { if (uri.getScheme().equals("file")) println("Classfile " + uri.getPath()); else println("Classfile " + uri); } indent(+1); if (lastModified != -1) { Date lm = new Date(lastModified); DateFormat df = DateFormat.getDateInstance(); if (size > 0) { println("Last modified " + df.format(lm) + "; size " + size + " bytes"); } else { println("Last modified " + df.format(lm)); } } else if (size > 0) { println("Size " + size + " bytes"); } if (digestName != null && digest != null) { StringBuilder sb = new StringBuilder(); for (byte b: digest) sb.append(String.format("%02x", b)); println(digestName + " checksum " + sb); } } Attribute sfa = cf.getAttribute(Attribute.SourceFile); if (sfa instanceof SourceFile_attribute) { println("Compiled from \"" + getSourceFile((SourceFile_attribute) sfa) + "\""); } if (options.sysInfo || options.verbose) { indent(-1); } AccessFlags flags = cf.access_flags; writeModifiers(flags.getClassModifiers()); if (classFile.access_flags.is(AccessFlags.ACC_MODULE)) { Attribute attr = classFile.attributes.get(Attribute.Module); if (attr instanceof Module_attribute) { Module_attribute modAttr = (Module_attribute) attr; String name; try { // FIXME: compatibility code if (constant_pool.get(modAttr.module_name).getTag() == CONSTANT_Module) { name = getJavaName(constant_pool.getModuleInfo(modAttr.module_name).getName()); } else { name = getJavaName(constant_pool.getUTF8Value(modAttr.module_name)); } } catch (ConstantPoolException e) { name = report(e); } if ((modAttr.module_flags & Module_attribute.ACC_OPEN) != 0) { print("open "); } print("module "); print(name); if (modAttr.module_version_index != 0) { print("@"); print(getUTF8Value(modAttr.module_version_index)); } } else { // fallback for malformed class files print("class "); print(getJavaName(classFile)); } } else { if (classFile.isClass()) print("class "); else if (classFile.isInterface()) print("interface "); print(getJavaName(classFile)); } Signature_attribute sigAttr = getSignature(cf.attributes); if (sigAttr == null) { // use info from class file header if (classFile.isClass() && classFile.super_class != 0 ) { String sn = getJavaSuperclassName(cf); if (!sn.equals("java.lang.Object")) { print(" extends "); print(sn); } } for (int i = 0; i < classFile.interfaces.length; i++) { print(i == 0 ? (classFile.isClass() ? " implements " : " extends ") : ","); print(getJavaInterfaceName(classFile, i)); } } else { try { Type t = sigAttr.getParsedSignature().getType(constant_pool); JavaTypePrinter p = new JavaTypePrinter(classFile.isInterface()); // The signature parser cannot disambiguate between a // FieldType and a ClassSignatureType that only contains a superclass type. if (t instanceof Type.ClassSigType) { print(p.print(t)); } else if (options.verbose || !t.isObject()) { print(" extends "); print(p.print(t)); } } catch (ConstantPoolException e) { print(report(e)); } } if (options.verbose) { println(); indent(+1); println("minor version: " + cf.minor_version); println("major version: " + cf.major_version); writeList(String.format("flags: (0x%04x) ", flags.flags), flags.getClassFlags(), "\n"); print("this_class: #" + cf.this_class); if (cf.this_class != 0) { tab(); print("// " + constantWriter.stringValue(cf.this_class)); } println(); print("super_class: #" + cf.super_class); if (cf.super_class != 0) { tab(); print("// " + constantWriter.stringValue(cf.super_class)); } println(); print("interfaces: " + cf.interfaces.length); print(", fields: " + cf.fields.length); print(", methods: " + cf.methods.length); println(", attributes: " + cf.attributes.attrs.length); indent(-1); constantWriter.writeConstantPool(); } else { print(" "); } println("{"); indent(+1); if (flags.is(AccessFlags.ACC_MODULE) && !options.verbose) { writeDirectives(); } writeFields(); writeMethods(); indent(-1); println("}"); if (options.verbose) { attrWriter.write(cf, cf.attributes, constant_pool); } } // where class JavaTypePrinter implements Type.Visitor { boolean isInterface; JavaTypePrinter(boolean isInterface) { this.isInterface = isInterface; } String print(Type t) { return t.accept(this, new StringBuilder()).toString(); } String printTypeArgs(List typeParamTypes) { StringBuilder builder = new StringBuilder(); appendIfNotEmpty(builder, "<", typeParamTypes, "> "); return builder.toString(); } @Override public StringBuilder visitSimpleType(SimpleType type, StringBuilder sb) { sb.append(getJavaName(type.name)); return sb; } @Override public StringBuilder visitArrayType(ArrayType type, StringBuilder sb) { append(sb, type.elemType); sb.append("[]"); return sb; } @Override public StringBuilder visitMethodType(MethodType type, StringBuilder sb) { appendIfNotEmpty(sb, "<", type.typeParamTypes, "> "); append(sb, type.returnType); append(sb, " (", type.paramTypes, ")"); appendIfNotEmpty(sb, " throws ", type.throwsTypes, ""); return sb; } @Override public StringBuilder visitClassSigType(ClassSigType type, StringBuilder sb) { appendIfNotEmpty(sb, "<", type.typeParamTypes, ">"); if (isInterface) { appendIfNotEmpty(sb, " extends ", type.superinterfaceTypes, ""); } else { if (type.superclassType != null && (options.verbose || !type.superclassType.isObject())) { sb.append(" extends "); append(sb, type.superclassType); } appendIfNotEmpty(sb, " implements ", type.superinterfaceTypes, ""); } return sb; } @Override public StringBuilder visitClassType(ClassType type, StringBuilder sb) { if (type.outerType != null) { append(sb, type.outerType); sb.append("."); } sb.append(getJavaName(type.name)); appendIfNotEmpty(sb, "<", type.typeArgs, ">"); return sb; } @Override public StringBuilder visitTypeParamType(TypeParamType type, StringBuilder sb) { sb.append(type.name); String sep = " extends "; if (type.classBound != null && (options.verbose || !type.classBound.isObject())) { sb.append(sep); append(sb, type.classBound); sep = " & "; } if (type.interfaceBounds != null) { for (Type bound: type.interfaceBounds) { sb.append(sep); append(sb, bound); sep = " & "; } } return sb; } @Override public StringBuilder visitWildcardType(WildcardType type, StringBuilder sb) { switch (type.kind) { case UNBOUNDED: sb.append("?"); break; case EXTENDS: sb.append("? extends "); append(sb, type.boundType); break; case SUPER: sb.append("? super "); append(sb, type.boundType); break; default: throw new AssertionError(); } return sb; } private void append(StringBuilder sb, Type t) { t.accept(this, sb); } private void append(StringBuilder sb, String prefix, List list, String suffix) { sb.append(prefix); String sep = ""; for (Type t: list) { sb.append(sep); append(sb, t); sep = ", "; } sb.append(suffix); } private void appendIfNotEmpty(StringBuilder sb, String prefix, List list, String suffix) { if (!isEmpty(list)) append(sb, prefix, list, suffix); } private boolean isEmpty(List list) { return (list == null || list.isEmpty()); } } protected void writeFields() { for (Field f: classFile.fields) { writeField(f); } } protected void writeField(Field f) { if (!options.checkAccess(f.access_flags)) return; AccessFlags flags = f.access_flags; writeModifiers(flags.getFieldModifiers()); Signature_attribute sigAttr = getSignature(f.attributes); if (sigAttr == null) print(getJavaFieldType(f.descriptor)); else { try { Type t = sigAttr.getParsedSignature().getType(constant_pool); print(getJavaName(t.toString())); } catch (ConstantPoolException e) { // report error? // fall back on non-generic descriptor print(getJavaFieldType(f.descriptor)); } } print(" "); print(getFieldName(f)); if (options.showConstants) { Attribute a = f.attributes.get(Attribute.ConstantValue); if (a instanceof ConstantValue_attribute) { print(" = "); ConstantValue_attribute cv = (ConstantValue_attribute) a; print(getConstantValue(f.descriptor, cv.constantvalue_index)); } } print(";"); println(); indent(+1); boolean showBlank = false; if (options.showDescriptors) println("descriptor: " + getValue(f.descriptor)); if (options.verbose) writeList(String.format("flags: (0x%04x) ", flags.flags), flags.getFieldFlags(), "\n"); if (options.showAllAttrs) { for (Attribute attr: f.attributes) attrWriter.write(f, attr, constant_pool); showBlank = true; } indent(-1); if (showBlank || options.showDisassembled || options.showLineAndLocalVariableTables) println(); } protected void writeMethods() { for (Method m: classFile.methods) writeMethod(m); setPendingNewline(false); } protected void writeMethod(Method m) { if (!options.checkAccess(m.access_flags)) return; method = m; AccessFlags flags = m.access_flags; Descriptor d; Type.MethodType methodType; List methodExceptions; Signature_attribute sigAttr = getSignature(m.attributes); if (sigAttr == null) { d = m.descriptor; methodType = null; methodExceptions = null; } else { Signature methodSig = sigAttr.getParsedSignature(); d = methodSig; try { methodType = (Type.MethodType) methodSig.getType(constant_pool); methodExceptions = methodType.throwsTypes; if (methodExceptions != null && methodExceptions.isEmpty()) methodExceptions = null; } catch (ConstantPoolException e) { // report error? // fall back on standard descriptor methodType = null; methodExceptions = null; } } writeModifiers(flags.getMethodModifiers()); if (methodType != null) { print(new JavaTypePrinter(false).printTypeArgs(methodType.typeParamTypes)); } switch (getName(m)) { case "": print(getJavaName(classFile)); print(getJavaParameterTypes(d, flags)); break; case "": print("{}"); break; default: print(getJavaReturnType(d)); print(" "); print(getName(m)); print(getJavaParameterTypes(d, flags)); break; } Attribute e_attr = m.attributes.get(Attribute.Exceptions); if (e_attr != null) { // if there are generic exceptions, there must be erased exceptions if (e_attr instanceof Exceptions_attribute) { Exceptions_attribute exceptions = (Exceptions_attribute) e_attr; print(" throws "); if (methodExceptions != null) { // use generic list if available writeList("", methodExceptions, ""); } else { for (int i = 0; i < exceptions.number_of_exceptions; i++) { if (i > 0) print(", "); print(getJavaException(exceptions, i)); } } } else { report("Unexpected or invalid value for Exceptions attribute"); } } println(";"); indent(+1); if (options.showDescriptors) { println("descriptor: " + getValue(m.descriptor)); } if (options.verbose) { writeList(String.format("flags: (0x%04x) ", flags.flags), flags.getMethodFlags(), "\n"); } Code_attribute code = null; Attribute c_attr = m.attributes.get(Attribute.Code); if (c_attr != null) { if (c_attr instanceof Code_attribute) code = (Code_attribute) c_attr; else report("Unexpected or invalid value for Code attribute"); } if (options.showAllAttrs) { Attribute[] attrs = m.attributes.attrs; for (Attribute attr: attrs) attrWriter.write(m, attr, constant_pool); } else if (code != null) { if (options.showDisassembled) { println("Code:"); codeWriter.writeInstrs(code); codeWriter.writeExceptionTable(code); } if (options.showLineAndLocalVariableTables) { attrWriter.write(code, code.attributes.get(Attribute.LineNumberTable), constant_pool); attrWriter.write(code, code.attributes.get(Attribute.LocalVariableTable), constant_pool); } } indent(-1); // set pendingNewline to write a newline before the next method (if any) // if a separator is desired setPendingNewline( options.showDisassembled || options.showAllAttrs || options.showDescriptors || options.showLineAndLocalVariableTables || options.verbose); } void writeModifiers(Collection items) { for (Object item: items) { print(item); print(" "); } } void writeDirectives() { Attribute attr = classFile.attributes.get(Attribute.Module); if (!(attr instanceof Module_attribute)) return; Module_attribute m = (Module_attribute) attr; for (Module_attribute.RequiresEntry entry: m.requires) { print("requires"); if ((entry.requires_flags & Module_attribute.ACC_STATIC_PHASE) != 0) print(" static"); if ((entry.requires_flags & Module_attribute.ACC_TRANSITIVE) != 0) print(" transitive"); print(" "); String mname; try { mname = getModuleName(entry.requires_index); } catch (ConstantPoolException e) { mname = report(e); } print(mname); println(";"); } for (Module_attribute.ExportsEntry entry: m.exports) { print("exports"); print(" "); String pname; try { pname = getPackageName(entry.exports_index).replace('/', '.'); } catch (ConstantPoolException e) { pname = report(e); } print(pname); boolean first = true; for (int i: entry.exports_to_index) { String mname; try { mname = getModuleName(i); } catch (ConstantPoolException e) { mname = report(e); } if (first) { println(" to"); indent(+1); first = false; } else { println(","); } print(mname); } println(";"); if (!first) indent(-1); } for (Module_attribute.OpensEntry entry: m.opens) { print("opens"); print(" "); String pname; try { pname = getPackageName(entry.opens_index).replace('/', '.'); } catch (ConstantPoolException e) { pname = report(e); } print(pname); boolean first = true; for (int i: entry.opens_to_index) { String mname; try { mname = getModuleName(i); } catch (ConstantPoolException e) { mname = report(e); } if (first) { println(" to"); indent(+1); first = false; } else { println(","); } print(mname); } println(";"); if (!first) indent(-1); } for (int entry: m.uses_index) { print("uses "); print(getClassName(entry).replace('/', '.')); println(";"); } for (Module_attribute.ProvidesEntry entry: m.provides) { print("provides "); print(getClassName(entry.provides_index).replace('/', '.')); boolean first = true; for (int i: entry.with_index) { if (first) { println(" with"); indent(+1); first = false; } else { println(","); } print(getClassName(i).replace('/', '.')); } println(";"); if (!first) indent(-1); } } String getModuleName(int index) throws ConstantPoolException { if (constant_pool.get(index).getTag() == CONSTANT_Module) { return constant_pool.getModuleInfo(index).getName(); } else { return constant_pool.getUTF8Value(index); } } String getPackageName(int index) throws ConstantPoolException { if (constant_pool.get(index).getTag() == CONSTANT_Package) { return constant_pool.getPackageInfo(index).getName(); } else { return constant_pool.getUTF8Value(index); } } String getUTF8Value(int index) { try { return classFile.constant_pool.getUTF8Value(index); } catch (ConstantPoolException e) { return report(e); } } String getClassName(int index) { try { return classFile.constant_pool.getClassInfo(index).getName(); } catch (ConstantPoolException e) { return report(e); } } void writeList(String prefix, Collection items, String suffix) { print(prefix); String sep = ""; for (Object item: items) { print(sep); print(item); sep = ", "; } print(suffix); } void writeListIfNotEmpty(String prefix, List items, String suffix) { if (items != null && items.size() > 0) writeList(prefix, items, suffix); } Signature_attribute getSignature(Attributes attributes) { return (Signature_attribute) attributes.get(Attribute.Signature); } String adjustVarargs(AccessFlags flags, String params) { if (flags.is(ACC_VARARGS)) { int i = params.lastIndexOf("[]"); if (i > 0) return params.substring(0, i) + "..." + params.substring(i+2); } return params; } String getJavaName(ClassFile cf) { try { return getJavaName(cf.getName()); } catch (ConstantPoolException e) { return report(e); } } String getJavaSuperclassName(ClassFile cf) { try { return getJavaName(cf.getSuperclassName()); } catch (ConstantPoolException e) { return report(e); } } String getJavaInterfaceName(ClassFile cf, int index) { try { return getJavaName(cf.getInterfaceName(index)); } catch (ConstantPoolException e) { return report(e); } } String getJavaFieldType(Descriptor d) { try { return getJavaName(d.getFieldType(constant_pool)); } catch (ConstantPoolException e) { return report(e); } catch (InvalidDescriptor e) { return report(e); } } String getJavaReturnType(Descriptor d) { try { return getJavaName(d.getReturnType(constant_pool)); } catch (ConstantPoolException e) { return report(e); } catch (InvalidDescriptor e) { return report(e); } } String getJavaParameterTypes(Descriptor d, AccessFlags flags) { try { return getJavaName(adjustVarargs(flags, d.getParameterTypes(constant_pool))); } catch (ConstantPoolException e) { return report(e); } catch (InvalidDescriptor e) { return report(e); } } String getJavaException(Exceptions_attribute attr, int index) { try { return getJavaName(attr.getException(index, constant_pool)); } catch (ConstantPoolException e) { return report(e); } } String getValue(Descriptor d) { try { return d.getValue(constant_pool); } catch (ConstantPoolException e) { return report(e); } } String getFieldName(Field f) { try { return f.getName(constant_pool); } catch (ConstantPoolException e) { return report(e); } } String getName(Method m) { try { return m.getName(constant_pool); } catch (ConstantPoolException e) { return report(e); } } static String getJavaName(String name) { return name.replace('/', '.'); } String getSourceFile(SourceFile_attribute attr) { try { return attr.getSourceFile(constant_pool); } catch (ConstantPoolException e) { return report(e); } } /** * Get the value of an entry in the constant pool as a Java constant. * Characters and booleans are represented by CONSTANT_Intgere entries. * Character and string values are processed to escape characters outside * the basic printable ASCII set. * @param d the descriptor, giving the expected type of the constant * @param index the index of the value in the constant pool * @return a printable string containing the value of the constant. */ String getConstantValue(Descriptor d, int index) { try { ConstantPool.CPInfo cpInfo = constant_pool.get(index); switch (cpInfo.getTag()) { case ConstantPool.CONSTANT_Integer: { ConstantPool.CONSTANT_Integer_info info = (ConstantPool.CONSTANT_Integer_info) cpInfo; String t = d.getValue(constant_pool); switch (t) { case "C": // character return getConstantCharValue((char) info.value); case "Z": // boolean return String.valueOf(info.value == 1); default: // other: assume integer return String.valueOf(info.value); } } case ConstantPool.CONSTANT_String: { ConstantPool.CONSTANT_String_info info = (ConstantPool.CONSTANT_String_info) cpInfo; return getConstantStringValue(info.getString()); } default: return constantWriter.stringValue(cpInfo); } } catch (ConstantPoolException e) { return "#" + index; } } private String getConstantCharValue(char c) { StringBuilder sb = new StringBuilder(); sb.append('\''); sb.append(esc(c, '\'')); sb.append('\''); return sb.toString(); } private String getConstantStringValue(String s) { StringBuilder sb = new StringBuilder(); sb.append("\""); for (int i = 0; i < s.length(); i++) { sb.append(esc(s.charAt(i), '"')); } sb.append("\""); return sb.toString(); } private String esc(char c, char quote) { if (32 <= c && c <= 126 && c != quote && c != '\\') return String.valueOf(c); else switch (c) { case '\b': return "\\b"; case '\n': return "\\n"; case '\t': return "\\t"; case '\f': return "\\f"; case '\r': return "\\r"; case '\\': return "\\\\"; case '\'': return "\\'"; case '\"': return "\\\""; default: return String.format("\\u%04x", (int) c); } } private final Options options; private final AttributeWriter attrWriter; private final CodeWriter codeWriter; private final ConstantWriter constantWriter; private ClassFile classFile; private URI uri; private long lastModified; private String digestName; private byte[] digest; private int size; private ConstantPool constant_pool; private Method method; }





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