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2202 lines (2102 loc) · 82.9 KB
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/***
* 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 clojure.asm;
import java.io.IOException;
import java.io.InputStream;
/**
* A Java class parser to make a {@link ClassVisitor} 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
*/
public class ClassReader {
/**
* True to enable signatures support.
*/
static final boolean SIGNATURES = true;
/**
* True to enable annotations support.
*/
static final boolean ANNOTATIONS = true;
/**
* True to enable stack map frames support.
*/
static final boolean FRAMES = true;
/**
* True to enable bytecode writing support.
*/
static final boolean WRITER = true;
/**
* True to enable JSR_W and GOTO_W support.
*/
static final boolean RESIZE = true;
/**
* Flag to skip method code. If this class is set <code>CODE</code>
* attribute won't be visited. This can be used, for example, to retrieve
* annotations for methods and method parameters.
*/
public static final int SKIP_CODE = 1;
/**
* Flag to skip the debug information in the class. If this flag is set the
* debug information of the class is not visited, i.e. the
* {@link MethodVisitor#visitLocalVariable visitLocalVariable} and
* {@link MethodVisitor#visitLineNumber visitLineNumber} methods will not be
* called.
*/
public static final int SKIP_DEBUG = 2;
/**
* Flag to skip the stack map frames in the class. If this flag is set the
* stack map frames of the class is not visited, i.e. the
* {@link MethodVisitor#visitFrame visitFrame} method will not be called.
* This flag is useful when the {@link ClassWriter#COMPUTE_FRAMES} option is
* used: it avoids visiting frames that will be ignored and recomputed from
* scratch in the class writer.
*/
public static final int SKIP_FRAMES = 4;
/**
* Flag to expand the stack map frames. By default stack map frames are
* visited in their original format (i.e. "expanded" for classes whose
* version is less than V1_6, and "compressed" for the other classes). If
* this flag is set, stack map frames are always visited in expanded format
* (this option adds a decompression/recompression step in ClassReader and
* ClassWriter which degrades performances quite a lot).
*/
public static final int EXPAND_FRAMES = 8;
/**
* The class to be parsed. <i>The content of this array must not be
* modified. This field is intended for {@link Attribute} sub classes, and
* is normally not needed by class generators or adapters.</i>
*/
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;
// ------------------------------------------------------------------------
// Constructors
// ------------------------------------------------------------------------
/**
* Constructs a new {@link ClassReader} object.
*
* @param b
* the bytecode of the class to be read.
*/
public ClassReader(final byte[] b) {
this(b, 0, b.length);
}
/**
* 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.
* @param len
* the length of the class data.
*/
public ClassReader(final byte[] b, final int off, final int len) {
this.b = b;
// checks the class version
if (readShort(off + 6) > Opcodes.V1_7) {
throw new IllegalArgumentException();
}
// 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 ClassWriter.FIELD:
case ClassWriter.METH:
case ClassWriter.IMETH:
case ClassWriter.INT:
case ClassWriter.FLOAT:
case ClassWriter.NAME_TYPE:
case ClassWriter.INDY:
size = 5;
break;
case ClassWriter.LONG:
case ClassWriter.DOUBLE:
size = 9;
++i;
break;
case ClassWriter.UTF8:
size = 3 + readUnsignedShort(index + 1);
if (size > max) {
max = size;
}
break;
case ClassWriter.HANDLE:
size = 4;
break;
// case ClassWriter.CLASS:
// case ClassWriter.STR:
// case ClassWriter.MTYPE
default:
size = 3;
break;
}
index += size;
}
maxStringLength = max;
// the class header information starts just after the constant pool
header = index;
}
/**
* Returns the class's access flags (see {@link Opcodes}). This value may
* not reflect Deprecated and Synthetic flags when bytecode is before 1.5
* and those flags are represented by attributes.
*
* @return the class access flags
*
* @see ClassVisitor#visit(int, int, String, String, String, String[])
*/
public int getAccess() {
return readUnsignedShort(header);
}
/**
* Returns the internal name of the class (see
* {@link Type#getInternalName() getInternalName}).
*
* @return the internal class name
*
* @see ClassVisitor#visit(int, int, String, String, String, String[])
*/
public String getClassName() {
return readClass(header + 2, new char[maxStringLength]);
}
/**
* Returns the internal of name of the super class (see
* {@link Type#getInternalName() getInternalName}). For interfaces, the
* super class is {@link Object}.
*
* @return the internal name of super class, or <tt>null</tt> for
* {@link Object} class.
*
* @see ClassVisitor#visit(int, int, String, String, String, String[])
*/
public String getSuperName() {
return readClass(header + 4, new char[maxStringLength]);
}
/**
* Returns the internal names of the class's interfaces (see
* {@link Type#getInternalName() getInternalName}).
*
* @return the array of internal names for all implemented interfaces or
* <tt>null</tt>.
*
* @see ClassVisitor#visit(int, int, String, String, String, String[])
*/
public String[] getInterfaces() {
int index = header + 6;
int n = readUnsignedShort(index);
String[] interfaces = new String[n];
if (n > 0) {
char[] buf = new char[maxStringLength];
for (int i = 0; i < n; ++i) {
index += 2;
interfaces[i] = readClass(index, buf);
}
}
return interfaces;
}
/**
* Copies the constant pool data into the given {@link ClassWriter}. Should
* be called before the {@link #accept(ClassVisitor,int)} method.
*
* @param classWriter
* the {@link ClassWriter} to copy constant pool into.
*/
void copyPool(final ClassWriter classWriter) {
char[] buf = new char[maxStringLength];
int ll = items.length;
Item[] items2 = new Item[ll];
for (int i = 1; i < ll; i++) {
int index = items[i];
int tag = b[index - 1];
Item item = new Item(i);
int nameType;
switch (tag) {
case ClassWriter.FIELD:
case ClassWriter.METH:
case ClassWriter.IMETH:
nameType = items[readUnsignedShort(index + 2)];
item.set(tag, readClass(index, buf), readUTF8(nameType, buf),
readUTF8(nameType + 2, buf));
break;
case ClassWriter.INT:
item.set(readInt(index));
break;
case ClassWriter.FLOAT:
item.set(Float.intBitsToFloat(readInt(index)));
break;
case ClassWriter.NAME_TYPE:
item.set(tag, readUTF8(index, buf), readUTF8(index + 2, buf),
null);
break;
case ClassWriter.LONG:
item.set(readLong(index));
++i;
break;
case ClassWriter.DOUBLE:
item.set(Double.longBitsToDouble(readLong(index)));
++i;
break;
case ClassWriter.UTF8: {
String s = strings[i];
if (s == null) {
index = items[i];
s = strings[i] = readUTF(index + 2,
readUnsignedShort(index), buf);
}
item.set(tag, s, null, null);
break;
}
case ClassWriter.HANDLE: {
int fieldOrMethodRef = items[readUnsignedShort(index + 1)];
nameType = items[readUnsignedShort(fieldOrMethodRef + 2)];
item.set(ClassWriter.HANDLE_BASE + readByte(index),
readClass(fieldOrMethodRef, buf),
readUTF8(nameType, buf), readUTF8(nameType + 2, buf));
break;
}
case ClassWriter.INDY:
if (classWriter.bootstrapMethods == null) {
copyBootstrapMethods(classWriter, items2, buf);
}
nameType = items[readUnsignedShort(index + 2)];
item.set(readUTF8(nameType, buf), readUTF8(nameType + 2, buf),
readUnsignedShort(index));
break;
// case ClassWriter.STR:
// case ClassWriter.CLASS:
// case ClassWriter.MTYPE
default:
item.set(tag, readUTF8(index, buf), null, null);
break;
}
int index2 = item.hashCode % items2.length;
item.next = items2[index2];
items2[index2] = item;
}
int off = items[1] - 1;
classWriter.pool.putByteArray(b, off, header - off);
classWriter.items = items2;
classWriter.threshold = (int) (0.75d * ll);
classWriter.index = ll;
}
/**
* Copies the bootstrap method data into the given {@link ClassWriter}.
* Should be called before the {@link #accept(ClassVisitor,int)} method.
*
* @param classWriter
* the {@link ClassWriter} to copy bootstrap methods into.
*/
private void copyBootstrapMethods(final ClassWriter classWriter,
final Item[] items, final char[] c) {
// finds the "BootstrapMethods" attribute
int u = getAttributes();
boolean found = false;
for (int i = readUnsignedShort(u); i > 0; --i) {
String attrName = readUTF8(u + 2, c);
if ("BootstrapMethods".equals(attrName)) {
found = true;
break;
}
u += 6 + readInt(u + 4);
}
if (!found) {
return;
}
// copies the bootstrap methods in the class writer
int boostrapMethodCount = readUnsignedShort(u + 8);
for (int j = 0, v = u + 10; j < boostrapMethodCount; j++) {
int position = v - u - 10;
int hashCode = readConst(readUnsignedShort(v), c).hashCode();
for (int k = readUnsignedShort(v + 2); k > 0; --k) {
hashCode ^= readConst(readUnsignedShort(v + 4), c).hashCode();
v += 2;
}
v += 4;
Item item = new Item(j);
item.set(position, hashCode & 0x7FFFFFFF);
int index = item.hashCode % items.length;
item.next = items[index];
items[index] = item;
}
int attrSize = readInt(u + 4);
ByteVector bootstrapMethods = new ByteVector(attrSize + 62);
bootstrapMethods.putByteArray(b, u + 10, attrSize - 2);
classWriter.bootstrapMethodsCount = boostrapMethodCount;
classWriter.bootstrapMethods = bootstrapMethods;
}
/**
* 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.
*/
public ClassReader(final InputStream is) throws IOException {
this(readClass(is, false));
}
/**
* Constructs a new {@link ClassReader} object.
*
* @param name
* the binary qualified name of the class to be read.
* @throws IOException
* if an exception occurs during reading.
*/
public ClassReader(final String name) throws IOException {
this(readClass(
ClassLoader.getSystemResourceAsStream(name.replace('.', '/')
+ ".class"), true));
}
/**
* Reads the bytecode of a class.
*
* @param is
* an input stream from which to read the class.
* @param close
* true to close the input stream after reading.
* @return the bytecode read from the given input stream.
* @throws IOException
* if a problem occurs during reading.
*/
private static byte[] readClass(final InputStream is, boolean close)
throws IOException {
if (is == null) {
throw new IOException("Class not found");
}
try {
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;
}
}
} finally {
if (close) {
is.close();
}
}
}
// ------------------------------------------------------------------------
// 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.
* @param flags
* option flags that can be used to modify the default behavior
* of this class. See {@link #SKIP_DEBUG}, {@link #EXPAND_FRAMES}
* , {@link #SKIP_FRAMES}, {@link #SKIP_CODE}.
*/
public void accept(final ClassVisitor classVisitor, final int flags) {
accept(classVisitor, new Attribute[0], flags);
}
/**
* 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.
* @param attrs
* prototypes of the attributes that must be parsed during the
* visit of the class. Any attribute whose type is not equal to
* the type of one the prototypes will not be parsed: its byte
* array value will be passed unchanged to the ClassWriter.
* <i>This may corrupt it if this value contains references to
* the constant pool, or has syntactic or semantic links with a
* class element that has been transformed by a class adapter
* between the reader and the writer</i>.
* @param flags
* option flags that can be used to modify the default behavior
* of this class. See {@link #SKIP_DEBUG}, {@link #EXPAND_FRAMES}
* , {@link #SKIP_FRAMES}, {@link #SKIP_CODE}.
*/
public void accept(final ClassVisitor classVisitor,
final Attribute[] attrs, final int flags) {
int u = header; // current offset in the class file
char[] c = new char[maxStringLength]; // buffer used to read strings
Context context = new Context();
context.attrs = attrs;
context.flags = flags;
context.buffer = c;
// reads the class declaration
int access = readUnsignedShort(u);
String name = readClass(u + 2, c);
String superClass = readClass(u + 4, c);
String[] interfaces = new String[readUnsignedShort(u + 6)];
u += 8;
for (int i = 0; i < interfaces.length; ++i) {
interfaces[i] = readClass(u, c);
u += 2;
}
// reads the class attributes
String signature = null;
String sourceFile = null;
String sourceDebug = null;
String enclosingOwner = null;
String enclosingName = null;
String enclosingDesc = null;
int anns = 0;
int ianns = 0;
int innerClasses = 0;
Attribute attributes = null;
u = getAttributes();
for (int i = readUnsignedShort(u); i > 0; --i) {
String attrName = readUTF8(u + 2, c);
// tests are sorted in decreasing frequency order
// (based on frequencies observed on typical classes)
if ("SourceFile".equals(attrName)) {
sourceFile = readUTF8(u + 8, c);
} else if ("InnerClasses".equals(attrName)) {
innerClasses = u + 8;
} else if ("EnclosingMethod".equals(attrName)) {
enclosingOwner = readClass(u + 8, c);
int item = readUnsignedShort(u + 10);
if (item != 0) {
enclosingName = readUTF8(items[item], c);
enclosingDesc = readUTF8(items[item] + 2, c);
}
} else if (SIGNATURES && "Signature".equals(attrName)) {
signature = readUTF8(u + 8, c);
} else if (ANNOTATIONS
&& "RuntimeVisibleAnnotations".equals(attrName)) {
anns = u + 8;
} else if ("Deprecated".equals(attrName)) {
access |= Opcodes.ACC_DEPRECATED;
} else if ("Synthetic".equals(attrName)) {
access |= Opcodes.ACC_SYNTHETIC
| ClassWriter.ACC_SYNTHETIC_ATTRIBUTE;
} else if ("SourceDebugExtension".equals(attrName)) {
int len = readInt(u + 4);
sourceDebug = readUTF(u + 8, len, new char[len]);
} else if (ANNOTATIONS
&& "RuntimeInvisibleAnnotations".equals(attrName)) {
ianns = u + 8;
} else if ("BootstrapMethods".equals(attrName)) {
int[] bootstrapMethods = new int[readUnsignedShort(u + 8)];
for (int j = 0, v = u + 10; j < bootstrapMethods.length; j++) {
bootstrapMethods[j] = v;
v += 2 + readUnsignedShort(v + 2) << 1;
}
context.bootstrapMethods = bootstrapMethods;
} else {
Attribute attr = readAttribute(attrs, attrName, u + 8,
readInt(u + 4), c, -1, null);
if (attr != null) {
attr.next = attributes;
attributes = attr;
}
}
u += 6 + readInt(u + 4);
}
// visits the class declaration
classVisitor.visit(readInt(items[1] - 7), access, name, signature,
superClass, interfaces);
// visits the source and debug info
if ((flags & SKIP_DEBUG) == 0
&& (sourceFile != null || sourceDebug != null)) {
classVisitor.visitSource(sourceFile, sourceDebug);
}
// visits the outer class
if (enclosingOwner != null) {
classVisitor.visitOuterClass(enclosingOwner, enclosingName,
enclosingDesc);
}
// visits the class annotations
if (ANNOTATIONS && anns != 0) {
for (int i = readUnsignedShort(anns), v = anns + 2; i > 0; --i) {
v = readAnnotationValues(v + 2, c, true,
classVisitor.visitAnnotation(readUTF8(v, c), true));
}
}
if (ANNOTATIONS && ianns != 0) {
for (int i = readUnsignedShort(ianns), v = ianns + 2; i > 0; --i) {
v = readAnnotationValues(v + 2, c, true,
classVisitor.visitAnnotation(readUTF8(v, c), false));
}
}
// visits the attributes
while (attributes != null) {
Attribute attr = attributes.next;
attributes.next = null;
classVisitor.visitAttribute(attributes);
attributes = attr;
}
// visits the inner classes
if (innerClasses != 0) {
int v = innerClasses + 2;
for (int i = readUnsignedShort(innerClasses); i > 0; --i) {
classVisitor.visitInnerClass(readClass(v, c),
readClass(v + 2, c), readUTF8(v + 4, c),
readUnsignedShort(v + 6));
v += 8;
}
}
// visits the fields and methods
u = header + 10 + 2 * interfaces.length;
for (int i = readUnsignedShort(u - 2); i > 0; --i) {
u = readField(classVisitor, context, u);
}
u += 2;
for (int i = readUnsignedShort(u - 2); i > 0; --i) {
u = readMethod(classVisitor, context, u);
}
// visits the end of the class
classVisitor.visitEnd();
}
/**
* Reads a field and makes the given visitor visit it.
*
* @param classVisitor
* the visitor that must visit the field.
* @param context
* information about the class being parsed.
* @param u
* the start offset of the field in the class file.
* @return the offset of the first byte following the field in the class.
*/
private int readField(final ClassVisitor classVisitor,
final Context context, int u) {
// reads the field declaration
char[] c = context.buffer;
int access = readUnsignedShort(u);
String name = readUTF8(u + 2, c);
String desc = readUTF8(u + 4, c);
u += 6;
// reads the field attributes
String signature = null;
int anns = 0;
int ianns = 0;
Object value = null;
Attribute attributes = null;
for (int i = readUnsignedShort(u); i > 0; --i) {
String attrName = readUTF8(u + 2, c);
// tests are sorted in decreasing frequency order
// (based on frequencies observed on typical classes)
if ("ConstantValue".equals(attrName)) {
int item = readUnsignedShort(u + 8);
value = item == 0 ? null : readConst(item, c);
} else if (SIGNATURES && "Signature".equals(attrName)) {
signature = readUTF8(u + 8, c);
} else if ("Deprecated".equals(attrName)) {
access |= Opcodes.ACC_DEPRECATED;
} else if ("Synthetic".equals(attrName)) {
access |= Opcodes.ACC_SYNTHETIC
| ClassWriter.ACC_SYNTHETIC_ATTRIBUTE;
} else if (ANNOTATIONS
&& "RuntimeVisibleAnnotations".equals(attrName)) {
anns = u + 8;
} else if (ANNOTATIONS
&& "RuntimeInvisibleAnnotations".equals(attrName)) {
ianns = u + 8;
} else {
Attribute attr = readAttribute(context.attrs, attrName, u + 8,
readInt(u + 4), c, -1, null);
if (attr != null) {
attr.next = attributes;
attributes = attr;
}
}
u += 6 + readInt(u + 4);
}
u += 2;
// visits the field declaration
FieldVisitor fv = classVisitor.visitField(access, name, desc,
signature, value);
if (fv == null) {
return u;
}
// visits the field annotations
if (ANNOTATIONS && anns != 0) {
for (int i = readUnsignedShort(anns), v = anns + 2; i > 0; --i) {
v = readAnnotationValues(v + 2, c, true,
fv.visitAnnotation(readUTF8(v, c), true));
}
}
if (ANNOTATIONS && ianns != 0) {
for (int i = readUnsignedShort(ianns), v = ianns + 2; i > 0; --i) {
v = readAnnotationValues(v + 2, c, true,
fv.visitAnnotation(readUTF8(v, c), false));
}
}
// visits the field attributes
while (attributes != null) {
Attribute attr = attributes.next;
attributes.next = null;
fv.visitAttribute(attributes);
attributes = attr;
}
// visits the end of the field
fv.visitEnd();
return u;
}
/**
* Reads a method and makes the given visitor visit it.
*
* @param classVisitor
* the visitor that must visit the method.
* @param context
* information about the class being parsed.
* @param u
* the start offset of the method in the class file.
* @return the offset of the first byte following the method in the class.
*/
private int readMethod(final ClassVisitor classVisitor,
final Context context, int u) {
// reads the method declaration
char[] c = context.buffer;
int access = readUnsignedShort(u);
String name = readUTF8(u + 2, c);
String desc = readUTF8(u + 4, c);
u += 6;
// reads the method attributes
int code = 0;
int exception = 0;
String[] exceptions = null;
String signature = null;
int anns = 0;
int ianns = 0;
int dann = 0;
int mpanns = 0;
int impanns = 0;
int firstAttribute = u;
Attribute attributes = null;
for (int i = readUnsignedShort(u); i > 0; --i) {
String attrName = readUTF8(u + 2, c);
// tests are sorted in decreasing frequency order
// (based on frequencies observed on typical classes)
if ("Code".equals(attrName)) {
if ((context.flags & SKIP_CODE) == 0) {
code = u + 8;
}
} else if ("Exceptions".equals(attrName)) {
exceptions = new String[readUnsignedShort(u + 8)];
exception = u + 10;
for (int j = 0; j < exceptions.length; ++j) {
exceptions[j] = readClass(exception, c);
exception += 2;
}
} else if (SIGNATURES && "Signature".equals(attrName)) {
signature = readUTF8(u + 8, c);
} else if ("Deprecated".equals(attrName)) {
access |= Opcodes.ACC_DEPRECATED;
} else if (ANNOTATIONS
&& "RuntimeVisibleAnnotations".equals(attrName)) {
anns = u + 8;
} else if (ANNOTATIONS && "AnnotationDefault".equals(attrName)) {
dann = u + 8;
} else if ("Synthetic".equals(attrName)) {
access |= Opcodes.ACC_SYNTHETIC
| ClassWriter.ACC_SYNTHETIC_ATTRIBUTE;
} else if (ANNOTATIONS
&& "RuntimeInvisibleAnnotations".equals(attrName)) {
ianns = u + 8;
} else if (ANNOTATIONS
&& "RuntimeVisibleParameterAnnotations".equals(attrName)) {
mpanns = u + 8;
} else if (ANNOTATIONS
&& "RuntimeInvisibleParameterAnnotations".equals(attrName)) {
impanns = u + 8;
} else {
Attribute attr = readAttribute(context.attrs, attrName, u + 8,
readInt(u + 4), c, -1, null);
if (attr != null) {
attr.next = attributes;
attributes = attr;
}
}
u += 6 + readInt(u + 4);
}
u += 2;
// visits the method declaration
MethodVisitor mv = classVisitor.visitMethod(access, name, desc,
signature, exceptions);
if (mv == null) {
return u;
}
/*
* if the returned MethodVisitor is in fact a MethodWriter, it means
* there is no method adapter between the reader and the writer. If, in
* addition, the writer's constant pool was copied from this reader
* (mw.cw.cr == this), and the signature and exceptions of the method
* have not been changed, then it is possible to skip all visit events
* and just copy the original code of the method to the writer (the
* access, name and descriptor can have been changed, this is not
* important since they are not copied as is from the reader).
*/
if (WRITER && mv instanceof MethodWriter) {
MethodWriter mw = (MethodWriter) mv;
if (mw.cw.cr == this && signature == mw.signature) {
boolean sameExceptions = false;
if (exceptions == null) {
sameExceptions = mw.exceptionCount == 0;
} else if (exceptions.length == mw.exceptionCount) {
sameExceptions = true;
for (int j = exceptions.length - 1; j >= 0; --j) {
exception -= 2;
if (mw.exceptions[j] != readUnsignedShort(exception)) {
sameExceptions = false;
break;
}
}
}
if (sameExceptions) {
/*
* we do not copy directly the code into MethodWriter to
* save a byte array copy operation. The real copy will be
* done in ClassWriter.toByteArray().
*/
mw.classReaderOffset = firstAttribute;
mw.classReaderLength = u - firstAttribute;
return u;
}
}
}
// visits the method annotations
if (ANNOTATIONS && dann != 0) {
AnnotationVisitor dv = mv.visitAnnotationDefault();
readAnnotationValue(dann, c, null, dv);
if (dv != null) {
dv.visitEnd();
}
}
if (ANNOTATIONS && anns != 0) {
for (int i = readUnsignedShort(anns), v = anns + 2; i > 0; --i) {
v = readAnnotationValues(v + 2, c, true,
mv.visitAnnotation(readUTF8(v, c), true));
}
}
if (ANNOTATIONS && ianns != 0) {
for (int i = readUnsignedShort(ianns), v = ianns + 2; i > 0; --i) {
v = readAnnotationValues(v + 2, c, true,
mv.visitAnnotation(readUTF8(v, c), false));
}
}
if (ANNOTATIONS && mpanns != 0) {
readParameterAnnotations(mpanns, desc, c, true, mv);
}
if (ANNOTATIONS && impanns != 0) {
readParameterAnnotations(impanns, desc, c, false, mv);
}
// visits the method attributes
while (attributes != null) {
Attribute attr = attributes.next;
attributes.next = null;
mv.visitAttribute(attributes);
attributes = attr;
}
// visits the method code
if (code != 0) {
context.access = access;
context.name = name;
context.desc = desc;
mv.visitCode();
readCode(mv, context, code);
}
// visits the end of the method
mv.visitEnd();
return u;
}
/**
* Reads the bytecode of a method and makes the given visitor visit it.
*
* @param mv
* the visitor that must visit the method's code.
* @param context
* information about the class being parsed.
* @param u
* the start offset of the code attribute in the class file.
*/
private void readCode(final MethodVisitor mv, final Context context, int u) {
// reads the header
byte[] b = this.b;
char[] c = context.buffer;
int maxStack = readUnsignedShort(u);
int maxLocals = readUnsignedShort(u + 2);
int codeLength = readInt(u + 4);
u += 8;
// reads the bytecode to find the labels
int codeStart = u;
int codeEnd = u + codeLength;
Label[] labels = new Label[codeLength + 2];
readLabel(codeLength + 1, labels);
while (u < codeEnd) {
int offset = u - codeStart;
int opcode = b[u] & 0xFF;
switch (ClassWriter.TYPE[opcode]) {
case ClassWriter.NOARG_INSN:
case ClassWriter.IMPLVAR_INSN:
u += 1;
break;
case ClassWriter.LABEL_INSN:
readLabel(offset + readShort(u + 1), labels);
u += 3;
break;
case ClassWriter.LABELW_INSN:
readLabel(offset + readInt(u + 1), labels);
u += 5;
break;
case ClassWriter.WIDE_INSN:
opcode = b[u + 1] & 0xFF;
if (opcode == Opcodes.IINC) {
u += 6;
} else {
u += 4;
}
break;
case ClassWriter.TABL_INSN:
// skips 0 to 3 padding bytes
u = u + 4 - (offset & 3);
// reads instruction
readLabel(offset + readInt(u), labels);
for (int i = readInt(u + 8) - readInt(u + 4) + 1; i > 0; --i) {