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/***
 *
 * Portions Copyright (c) 2007 Paul Hammant
 * Portions copyright (c) 2000-2007 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.weakref.jmx.internal.paranamer;

import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.AccessibleObject;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.HashMap;
import java.util.Map;


/**
 * An ASM-based implementation of Paranamer. It relies on debug information compiled
 * with the "-g" javac option to retrieve parameter names.
 * 

* Portions of this source file are a fork of ASM. * * @author Guilherme Silveira * @author Paul Hammant */ public class BytecodeReadingParanamer implements Paranamer { private static final Map primitives = new HashMap() { { put("int","I"); put("boolean","Z"); put("char","C"); put("short","B"); put("float","F"); put("long","J"); put("double","D"); } }; public String[] lookupParameterNames(AccessibleObject methodOrConstructor) { return lookupParameterNames(methodOrConstructor, true); } public String[] lookupParameterNames(AccessibleObject methodOrCtor, boolean throwExceptionIfMissing) { Class[] types = null; Class declaringClass = null; String name = null; if (methodOrCtor instanceof Method) { Method method = (Method) methodOrCtor; types = method.getParameterTypes(); name = method.getName(); declaringClass = method.getDeclaringClass(); } else { Constructor constructor = (Constructor) methodOrCtor; types = constructor.getParameterTypes(); declaringClass = constructor.getDeclaringClass(); name = ""; } if (types.length == 0) { return EMPTY_NAMES; } InputStream content = getClassAsStream(declaringClass); if (content == null) { if (throwExceptionIfMissing) { throw new ParameterNamesNotFoundException("Unable to get class bytes"); } else { return Paranamer.EMPTY_NAMES; } } try { ClassReader reader = new ClassReader(content); TypeCollector visitor = new TypeCollector(name, types, throwExceptionIfMissing); reader.accept(visitor); return visitor.getParameterNamesForMethod(); } catch (IOException e) { if (throwExceptionIfMissing) { throw new ParameterNamesNotFoundException("IoException while reading class bytes", e); } else { return Paranamer.EMPTY_NAMES; } } } private InputStream getClassAsStream(Class clazz) { ClassLoader classLoader = clazz.getClassLoader(); if (classLoader == null) { classLoader = ClassLoader.getSystemClassLoader(); } return getClassAsStream(classLoader, clazz.getName()); } private InputStream getClassAsStream(ClassLoader classLoader, String className) { String name = className.replace('.', '/') + ".class"; // better pre-cache all methods otherwise this content will be loaded // multiple times InputStream asStream = classLoader.getResourceAsStream(name); if (asStream == null) { asStream = BytecodeReadingParanamer.class.getResourceAsStream(name); } return asStream; } /** * The type collector waits for an specific method in order to start a method * collector. * * @author Guilherme Silveira */ private static class TypeCollector { private static final String COMMA = ","; private final String methodName; private final Class[] parameterTypes; private final boolean throwExceptionIfMissing; private MethodCollector collector; private boolean methodFound = false; private boolean classFound = false; private TypeCollector(String methodName, Class[] parameterTypes, boolean throwExceptionIfMissing) { this.methodName = methodName; this.parameterTypes = parameterTypes; this.throwExceptionIfMissing = throwExceptionIfMissing; this.collector = null; } public MethodCollector visitMethod(int access, String name, String desc) { // already found the method, skip any processing classFound = true; if (collector != null) { return null; } // not the same name if (!name.equals(methodName)) { return null; } methodFound = true; Type[] argumentTypes = Type.getArgumentTypes(desc); int longOrDoubleQuantity = 0; for (int i1 = 0; i1 < argumentTypes.length; i1++) { Type t = argumentTypes[i1]; if (t.getClassName().equals("long") || t.getClassName().equals("double")) { longOrDoubleQuantity++; } } int paramCount = argumentTypes.length; // not the same quantity of parameters if (paramCount != this.parameterTypes.length) { return null; } for (int i = 0; i < argumentTypes.length; i++) { if (!correctTypeName(argumentTypes, i).equals( this.parameterTypes[i].getName())) { return null; } } this.collector = new MethodCollector((Modifier.isStatic(access) ? 0 : 1), argumentTypes.length + longOrDoubleQuantity); return collector; } private String correctTypeName(Type[] argumentTypes, int i) { String s = argumentTypes[i].getClassName(); // array notation needs cleanup. if (s.endsWith("[]")) { String prefix = s.substring(0, s.length() - 2); if (primitives.containsKey(prefix)) { s = "[" + primitives.get(prefix); } else { s = "[L" + prefix + ";"; } } return s; } private String[] getParameterNamesForMethod() { if (collector == null) { return Paranamer.EMPTY_NAMES; } if (!collector.isDebugInfoPresent()) { if (throwExceptionIfMissing) { throw new ParameterNamesNotFoundException("Parameter names not found for " + methodName); } else { return Paranamer.EMPTY_NAMES; } } return collector.getResult().split(COMMA); } } /** * Objects of this class collects information from a specific method. * * @author Guilherme Silveira */ private static class MethodCollector { private final int paramCount; private final int ignoreCount; private int currentParameter; private final StringBuffer result; private boolean debugInfoPresent; private MethodCollector(int ignoreCount, int paramCount) { this.ignoreCount = ignoreCount; this.paramCount = paramCount; this.result = new StringBuffer(); this.currentParameter = 0; // if there are 0 parameters, there is no need for debug info this.debugInfoPresent = paramCount == 0 ? true : false; } public void visitLocalVariable(String name, int index) { if (index >= ignoreCount && index < ignoreCount + paramCount) { if (!name.equals("arg" + currentParameter)) { debugInfoPresent = true; } result.append(','); result.append(name); currentParameter++; } } private String getResult() { return result.length() != 0 ? result.substring(1) : ""; } private boolean isDebugInfoPresent() { return debugInfoPresent; } } /*** * Portions Copyright (c) 2007 Paul Hammant * Portions copyright (c) 2000-2007 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. */ /** * A Java class parser to make a Class Visitor visit an existing class. * This class parses a byte array conforming to the Java class file format and * calls the appropriate visit methods of a given class visitor for each field, * method and bytecode instruction encountered. * * @author Eric Bruneton * @author Eugene Kuleshov */ private static class ClassReader { /** * The class to be parsed. The content of this array must not be * modified. This field is intended for Attribute sub classes, and * is normally not needed by class generators or adapters. */ public final byte[] b; /** * The start index of each constant pool item in {@link #b b}, plus one. * The one byte offset skips the constant pool item tag that indicates its * type. */ private final int[] items; /** * The String objects corresponding to the CONSTANT_Utf8 items. This cache * avoids multiple parsing of a given CONSTANT_Utf8 constant pool item, * which GREATLY improves performances (by a factor 2 to 3). This caching * strategy could be extended to all constant pool items, but its benefit * would not be so great for these items (because they are much less * expensive to parse than CONSTANT_Utf8 items). */ private final String[] strings; /** * Maximum length of the strings contained in the constant pool of the * class. */ private final int maxStringLength; /** * Start index of the class header information (access, name...) in * {@link #b b}. */ public final int header; /** * The type of CONSTANT_Fieldref constant pool items. */ final static int FIELD = 9; /** * The type of CONSTANT_Methodref constant pool items. */ final static int METH = 10; /** * The type of CONSTANT_InterfaceMethodref constant pool items. */ final static int IMETH = 11; /** * The type of CONSTANT_Integer constant pool items. */ final static int INT = 3; /** * The type of CONSTANT_Float constant pool items. */ final static int FLOAT = 4; /** * The type of CONSTANT_Long constant pool items. */ final static int LONG = 5; /** * The type of CONSTANT_Double constant pool items. */ final static int DOUBLE = 6; /** * The type of CONSTANT_NameAndType constant pool items. */ final static int NAME_TYPE = 12; /** * The type of CONSTANT_Utf8 constant pool items. */ final static int UTF8 = 1; // ------------------------------------------------------------------------ // Constructors // ------------------------------------------------------------------------ /** * Constructs a new {@link ClassReader} object. * * @param b the bytecode of the class to be read. */ private ClassReader(final byte[] b) { this(b, 0); } /** * Constructs a new {@link ClassReader} object. * * @param b the bytecode of the class to be read. * @param off the start offset of the class data. */ private ClassReader(final byte[] b, final int off) { this.b = b; // parses the constant pool items = new int[readUnsignedShort(off + 8)]; int n = items.length; strings = new String[n]; int max = 0; int index = off + 10; for (int i = 1; i < n; ++i) { items[i] = index + 1; int size; switch (b[index]) { case FIELD: case METH: case IMETH: case INT: case FLOAT: case NAME_TYPE: size = 5; break; case LONG: case DOUBLE: size = 9; ++i; break; case UTF8: size = 3 + readUnsignedShort(index + 1); if (size > max) { max = size; } break; // case HamConstants.CLASS: // case HamConstants.STR: default: size = 3; break; } index += size; } maxStringLength = max; // the class header information starts just after the constant pool header = index; } /** * Constructs a new {@link ClassReader} object. * * @param is an input stream from which to read the class. * @throws IOException if a problem occurs during reading. */ private ClassReader(final InputStream is) throws IOException { this(readClass(is)); } /** * Reads the bytecode of a class. * * @param is an input stream from which to read the class. * @return the bytecode read from the given input stream. * @throws IOException if a problem occurs during reading. */ private static byte[] readClass(final InputStream is) throws IOException { if (is == null) { throw new IOException("Class not found"); } byte[] b = new byte[is.available()]; int len = 0; while (true) { int n = is.read(b, len, b.length - len); if (n == -1) { if (len < b.length) { byte[] c = new byte[len]; System.arraycopy(b, 0, c, 0, len); b = c; } return b; } len += n; if (len == b.length) { int last = is.read(); if (last < 0) { return b; } byte[] c = new byte[b.length + 1000]; System.arraycopy(b, 0, c, 0, len); c[len++] = (byte) last; b = c; } } } // ------------------------------------------------------------------------ // Public methods // ------------------------------------------------------------------------ /** * Makes the given visitor visit the Java class of this {@link ClassReader}. * This class is the one specified in the constructor (see * {@link #ClassReader(byte[]) ClassReader}). * * @param classVisitor the visitor that must visit this class. */ private void accept(final TypeCollector classVisitor) { char[] c = new char[maxStringLength]; // buffer used to read strings int i, j, k; // loop variables int u, v, w; // indexes in b String attrName; int anns = 0; int ianns = 0; // visits the header u = header; v = items[readUnsignedShort(u + 4)]; int len = readUnsignedShort(u + 6); w = 0; u += 8; for (i = 0; i < len; ++i) { u += 2; } v = u; i = readUnsignedShort(v); v += 2; for (; i > 0; --i) { j = readUnsignedShort(v + 6); v += 8; for (; j > 0; --j) { v += 6 + readInt(v + 2); } } i = readUnsignedShort(v); v += 2; for (; i > 0; --i) { j = readUnsignedShort(v + 6); v += 8; for (; j > 0; --j) { v += 6 + readInt(v + 2); } } i = readUnsignedShort(v); v += 2; for (; i > 0; --i) { v += 6 + readInt(v + 2); } //annotations not needed. // visits the fields i = readUnsignedShort(u); u += 2; for (; i > 0; --i) { j = readUnsignedShort(u + 6); u += 8; for (; j > 0; --j) { u += 6 + readInt(u + 2); } } // visits the methods i = readUnsignedShort(u); u += 2; for (; i > 0; --i) { // inlined in original ASM source, now a method call u = readMethod(classVisitor, c, u); } } private int readMethod(TypeCollector classVisitor, char[] c, int u) { int v; int w; int j; String attrName; int k; int access = readUnsignedShort(u); String name = readUTF8(u + 2, c); String desc = readUTF8(u + 4, c); v = 0; w = 0; // looks for Code and Exceptions attributes j = readUnsignedShort(u + 6); u += 8; for (; j > 0; --j) { attrName = readUTF8(u, c); int attrSize = readInt(u + 2); u += 6; // tests are sorted in decreasing frequency order // (based on frequencies observed on typical classes) if (attrName.equals("Code")) { v = u; } u += attrSize; } // reads declared exceptions if (w == 0) { } else { w += 2; for (j = 0; j < readUnsignedShort(w); ++j) { w += 2; } } // visits the method's code, if any MethodCollector mv = classVisitor.visitMethod(access, name, desc); if (mv != null && v != 0) { int codeLength = readInt(v + 4); v += 8; int codeStart = v; int codeEnd = v + codeLength; v = codeEnd; j = readUnsignedShort(v); v += 2; for (; j > 0; --j) { v += 8; } // parses the local variable, line number tables, and code // attributes int varTable = 0; int varTypeTable = 0; j = readUnsignedShort(v); v += 2; for (; j > 0; --j) { attrName = readUTF8(v, c); if (attrName.equals("LocalVariableTable")) { varTable = v + 6; } else if (attrName.equals("LocalVariableTypeTable")) { varTypeTable = v + 6; } v += 6 + readInt(v + 2); } v = codeStart; // visits the local variable tables if (varTable != 0) { if (varTypeTable != 0) { k = readUnsignedShort(varTypeTable) * 3; w = varTypeTable + 2; int[] typeTable = new int[k]; while (k > 0) { typeTable[--k] = w + 6; // signature typeTable[--k] = readUnsignedShort(w + 8); // index typeTable[--k] = readUnsignedShort(w); // start w += 10; } } k = readUnsignedShort(varTable); w = varTable + 2; for (; k > 0; --k) { int index = readUnsignedShort(w + 8); mv.visitLocalVariable(readUTF8(w + 4, c), index); w += 10; } } } return u; } /** * Reads an unsigned short value in {@link #b b}. This method is * intended for Attribute sub classes, and is normally not needed by * class generators or adapters. * * @param index the start index of the value to be read in {@link #b b}. * @return the read value. */ private int readUnsignedShort(final int index) { byte[] b = this.b; return ((b[index] & 0xFF) << 8) | (b[index + 1] & 0xFF); } /** * Reads a signed int value in {@link #b b}. This method is intended for * Attribute sub classes, and is normally not needed by class * generators or adapters. * * @param index the start index of the value to be read in {@link #b b}. * @return the read value. */ private int readInt(final int index) { byte[] b = this.b; return ((b[index] & 0xFF) << 24) | ((b[index + 1] & 0xFF) << 16) | ((b[index + 2] & 0xFF) << 8) | (b[index + 3] & 0xFF); } /** * Reads an UTF8 string constant pool item in {@link #b b}. This method * is intended for Attribute sub classes, and is normally not needed * by class generators or adapters. * * @param index the start index of an unsigned short value in {@link #b b}, * whose value is the index of an UTF8 constant pool item. * @param buf buffer to be used to read the item. This buffer must be * sufficiently large. It is not automatically resized. * @return the String corresponding to the specified UTF8 item. */ private String readUTF8(int index, final char[] buf) { int item = readUnsignedShort(index); String s = strings[item]; if (s != null) { return s; } index = items[item]; return strings[item] = readUTF(index + 2, readUnsignedShort(index), buf); } /** * Reads UTF8 string in {@link #b b}. * * @param index start offset of the UTF8 string to be read. * @param utfLen length of the UTF8 string to be read. * @param buf buffer to be used to read the string. This buffer must be * sufficiently large. It is not automatically resized. * @return the String corresponding to the specified UTF8 string. */ private String readUTF(int index, final int utfLen, final char[] buf) { int endIndex = index + utfLen; byte[] b = this.b; int strLen = 0; int c; int st = 0; char cc = 0; while (index < endIndex) { c = b[index++]; switch (st) { case 0: c = c & 0xFF; if (c < 0x80) { // 0xxxxxxx buf[strLen++] = (char) c; } else if (c < 0xE0 && c > 0xBF) { // 110x xxxx 10xx xxxx cc = (char) (c & 0x1F); st = 1; } else { // 1110 xxxx 10xx xxxx 10xx xxxx cc = (char) (c & 0x0F); st = 2; } break; case 1: // byte 2 of 2-byte char or byte 3 of 3-byte char buf[strLen++] = (char) ((cc << 6) | (c & 0x3F)); st = 0; break; case 2: // byte 2 of 3-byte char cc = (char) ((cc << 6) | (c & 0x3F)); st = 1; break; } } return new String(buf, 0, strLen); } } /*** * Portions Copyright (c) 2007 Paul Hammant * Portions copyright (c) 2000-2007 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. */ /** * A Java type. This class can be used to make it easier to manipulate type and * method descriptors. * * @author Eric Bruneton * @author Chris Nokleberg */ private static class Type { /** * The sort of the void type. */ private final static int VOID = 0; /** * The sort of the boolean type. */ private final static int BOOLEAN = 1; /** * The sort of the char type. */ private final static int CHAR = 2; /** * The sort of the byte type. */ private final static int BYTE = 3; /** * The sort of the short type. */ private final static int SHORT = 4; /** * The sort of the int type. */ private final static int INT = 5; /** * The sort of the float type. */ private final static int FLOAT = 6; /** * The sort of the long type. */ private final static int LONG = 7; /** * The sort of the double type. */ private final static int DOUBLE = 8; /** * The sort of array reference types. */ private final static int ARRAY = 9; /** * The sort of object reference type. */ private final static int OBJECT = 10; /** * The void type. */ private final static Type VOID_TYPE = new Type(VOID); /** * The boolean type. */ private final static Type BOOLEAN_TYPE = new Type(BOOLEAN); /** * The char type. */ private final static Type CHAR_TYPE = new Type(CHAR); /** * The byte type. */ private final static Type BYTE_TYPE = new Type(BYTE); /** * The short type. */ private final static Type SHORT_TYPE = new Type(SHORT); /** * The int type. */ private final static Type INT_TYPE = new Type(INT); /** * The float type. */ private final static Type FLOAT_TYPE = new Type(FLOAT); /** * The long type. */ private final static Type LONG_TYPE = new Type(LONG); /** * The double type. */ private final static Type DOUBLE_TYPE = new Type(DOUBLE); // ------------------------------------------------------------------------ // Fields // ------------------------------------------------------------------------ /** * The sort of this Java type. */ private final int sort; /** * A buffer containing the internal name of this Java type. This field is * only used for reference types. */ private char[] buf; /** * The offset of the internal name of this Java type in {@link #buf buf}. * This field is only used for reference types. */ private int off; /** * The length of the internal name of this Java type. This field is only * used for reference types. */ private final int len; // ------------------------------------------------------------------------ // Constructors // ------------------------------------------------------------------------ /** * Constructs a primitive type. * * @param sort the sort of the primitive type to be constructed. */ private Type(final int sort) { this.sort = sort; this.len = 1; } /** * Constructs a reference type. * * @param sort the sort of the reference type to be constructed. * @param buf a buffer containing the descriptor of the previous type. * @param off the offset of this descriptor in the previous buffer. * @param len the length of this descriptor. */ private Type(final int sort, final char[] buf, final int off, final int len) { this.sort = sort; this.buf = buf; this.off = off; this.len = len; } /** * Returns the Java types corresponding to the argument types of the given * method descriptor. * * @param methodDescriptor a method descriptor. * @return the Java types corresponding to the argument types of the given * method descriptor. */ private static Type[] getArgumentTypes(final String methodDescriptor) { char[] buf = methodDescriptor.toCharArray(); int off = 1; int size = 0; while (true) { char car = buf[off++]; if (car == ')') { break; } else if (car == 'L') { while (buf[off++] != ';') { } ++size; } else if (car != '[') { ++size; } } Type[] args = new Type[size]; off = 1; size = 0; while (buf[off] != ')') { args[size] = getType(buf, off); off += args[size].len + (args[size].sort == OBJECT ? 2 : 0); size += 1; } return args; } /** * Returns the Java type corresponding to the given type descriptor. * * @param buf a buffer containing a type descriptor. * @param off the offset of this descriptor in the previous buffer. * @return the Java type corresponding to the given type descriptor. */ private static Type getType(final char[] buf, final int off) { int len; switch (buf[off]) { case 'V': return VOID_TYPE; case 'Z': return BOOLEAN_TYPE; case 'C': return CHAR_TYPE; case 'B': return BYTE_TYPE; case 'S': return SHORT_TYPE; case 'I': return INT_TYPE; case 'F': return FLOAT_TYPE; case 'J': return LONG_TYPE; case 'D': return DOUBLE_TYPE; case '[': len = 1; while (buf[off + len] == '[') { ++len; } if (buf[off + len] == 'L') { ++len; while (buf[off + len] != ';') { ++len; } } return new Type(ARRAY, buf, off, len + 1); // case 'L': default: len = 1; while (buf[off + len] != ';') { ++len; } return new Type(OBJECT, buf, off + 1, len - 1); } } // ------------------------------------------------------------------------ // Accessors // ------------------------------------------------------------------------ /** * Returns the number of dimensions of this array type. This method should * only be used for an array type. * * @return the number of dimensions of this array type. */ private int getDimensions() { int i = 1; while (buf[off + i] == '[') { ++i; } return i; } /** * Returns the type of the elements of this array type. This method should * only be used for an array type. * * @return Returns the type of the elements of this array type. */ private Type getElementType() { return getType(buf, off + getDimensions()); } /** * Returns the name of the class corresponding to this type. * * @return the fully qualified name of the class corresponding to this type. */ private String getClassName() { switch (sort) { case VOID: return "void"; case BOOLEAN: return "boolean"; case CHAR: return "char"; case BYTE: return "byte"; case SHORT: return "short"; case INT: return "int"; case FLOAT: return "float"; case LONG: return "long"; case DOUBLE: return "double"; case ARRAY: StringBuffer b = new StringBuffer(getElementType().getClassName()); for (int i = getDimensions(); i > 0; --i) { b.append("[]"); } return b.toString(); // case OBJECT: default: return new String(buf, off, len).replace('/', '.'); } } } }





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