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JMockit is a Java toolkit for automated developer testing.
It contains APIs for the creation of the objects to be tested, for mocking dependencies, and for faking external
APIs; JUnit (4 & 5) and TestNG test runners are supported.
It also contains an advanced code coverage tool.
/*
* 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 mockit.external.asm;
import java.io.*;
import javax.annotation.*;
import static mockit.external.asm.ConstantPoolItemType.*;
/**
* 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.
*/
public final class ClassReader extends AnnotatedReader
{
/**
* Flag to skip method code. If this class is set 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} and {@link MethodVisitor#visitLineNumber} methods will
* not be called.
*/
public static final int SKIP_DEBUG = 2;
private static final String[] NO_INTERFACES = {};
// Helper fields.
ClassVisitor cv;
private Context context;
int access;
private String name;
@Nullable private String superClass;
@Nonnull private String[] interfaces = NO_INTERFACES;
@Nullable private String signature;
@Nullable private String sourceFile;
@Nullable private String sourceDebug;
@Nullable private EnclosingMethod enclosingMethod;
/**
* Constructs a new {@link ClassReader} object.
*
* @param bytecode the bytecode of the class to be read.
*/
public ClassReader(@Nonnull byte[] bytecode) { super(bytecode); }
/**
* 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(@Nonnull InputStream is) throws IOException {
this(readClass(is));
}
@Nonnull
private static byte[] readClass(@Nonnull InputStream is) throws IOException {
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 {
is.close();
}
}
/**
* Returns the classfile version of the class being read.
*/
public int getVersion() {
return readShort(6);
}
/**
* 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 JavaType#getInternalName()}).
*
* @return the internal class name
* @see ClassVisitor#visit(int, int, String, String, String, String[])
*/
public String getClassName() {
return readClass(header + 2);
}
/**
* Returns the internal of name of the super class (see {@link JavaType#getInternalName()}).
* For interfaces, the super class is {@link Object}.
*
* @return the internal name of super class, or null for {@link Object} class.
* @see ClassVisitor#visit(int, int, String, String, String, String[])
*/
@Nullable
public String getSuperName() {
return readClass(header + 4);
}
/**
* Returns the internal names of the class's interfaces (see {@link JavaType#getInternalName()}).
*
* @return the array of internal names for all implemented interfaces or null.
* @see ClassVisitor#visit(int, int, String, String, String, String[])
*/
@Nonnull
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}.
*/
void copyPool(@Nonnull ClassWriter cw) {
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 FIELD:
case METH:
case IMETH:
nameType = items[readUnsignedShort(index + 2)];
item.set(tag, readClass(index, buf), readUTF8(nameType, buf), readUTF8(nameType + 2, buf));
break;
case INT:
item.set(readInt(index));
break;
case FLOAT:
item.set(Float.intBitsToFloat(readInt(index)));
break;
case NAME_TYPE:
item.set(tag, readUTF8(index, buf), readUTF8(index + 2, buf), null);
break;
case LONG:
item.set(readLong(index));
i++;
break;
case DOUBLE:
item.set(Double.longBitsToDouble(readLong(index)));
i++;
break;
case UTF8:
copyUTF8Item(buf, i, tag, item);
break;
case HANDLE:
copyHandleItem(buf, index, item);
break;
case INDY:
copyInvokeDynamicItem(cw, buf, items2, index, item);
break;
// case STR|CLASS|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;
cw.cp.copy(b, off, header, items2);
}
private void copyUTF8Item(@Nonnull char[] buf, @Nonnegative int i, int tag, @Nonnull Item item) {
String s = strings[i];
if (s == null) {
int index = items[i];
s = strings[i] = readUTF(index + 2, readUnsignedShort(index), buf);
}
item.set(tag, s, null, null);
}
private void copyHandleItem(@Nonnull char[] buf, @Nonnegative int index, @Nonnull Item item) {
int fieldOrMethodRef = items[readUnsignedShort(index + 1)];
int nameType = items[readUnsignedShort(fieldOrMethodRef + 2)];
int type = HANDLE_BASE + readByte(index);
String classDesc = readClass(fieldOrMethodRef, buf);
String name = readUTF8(nameType, buf);
String desc = readUTF8(nameType + 2, buf);
item.set(type, classDesc, name, desc);
}
private void copyInvokeDynamicItem(
@Nonnull ClassWriter cw, @Nonnull char[] buf, @Nonnull Item[] items2, @Nonnegative int index, @Nonnull Item item
) {
cw.bootstrapMethods.copyBootstrapMethods(this, items2, buf);
int nameType = items[readUnsignedShort(index + 2)];
String name = readUTF8(nameType, buf);
String desc = readUTF8(nameType + 2, buf);
int bsmIndex = readUnsignedShort(index);
//noinspection ConstantConditions
item.set(name, desc, bsmIndex);
}
/**
* Makes the given visitor visit the Java class of this {@link ClassReader}, all attributes included.
*/
public void accept(ClassVisitor cv) {
accept(cv, 0);
}
/**
* Makes the given visitor visit the Java class of this {@link ClassReader}.
*
* @param cv 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_CODE}, {@link #SKIP_DEBUG}.
*/
public void accept(@Nonnull ClassVisitor cv, int flags) {
this.cv = cv;
char[] c = new char[maxStringLength]; // buffer used to read strings
context = new Context(flags, c);
readClassDeclaration();
readInterfaces();
// Reads the class attributes.
signature = null;
sourceFile = null;
sourceDebug = null;
enclosingMethod = null;
int annotations = 0;
int innerClasses = 0;
int u = getAttributesStartIndex();
for (int i = readUnsignedShort(u); i > 0; i--) {
String attrName = readUTF8(u + 2, c);
if ("SourceFile".equals(attrName)) {
sourceFile = readUTF8(u + 8, c);
}
else if ("InnerClasses".equals(attrName)) {
innerClasses = u + 8;
}
else if ("EnclosingMethod".equals(attrName)) {
enclosingMethod = new EnclosingMethod(this, c, u);
}
else if ("Signature".equals(attrName)) {
signature = readUTF8(u + 8, c);
}
else if ("RuntimeVisibleAnnotations".equals(attrName)) {
annotations = u + 8;
}
else if ("Deprecated".equals(attrName)) {
access = Access.asDeprecated(access);
}
else if ("Synthetic".equals(attrName)) {
access = Access.asSynthetic(access);
}
else if ("SourceDebugExtension".equals(attrName)) {
int len = readInt(u + 4);
sourceDebug = readUTF(u + 8, len, new char[len]);
}
else if ("BootstrapMethods".equals(attrName)) {
readBootstrapMethods(u);
}
u += 6 + readInt(u + 4);
}
readClass();
readSourceAndDebugInfo();
readOuterClass();
readAnnotations(annotations);
readInnerClasses(innerClasses);
readFieldsAndMethods();
cv.visitEnd();
}
private void readClassDeclaration() {
int u = header;
char[] c = context.buffer;
access = readUnsignedShort(u);
name = readClass(u + 2, c);
superClass = readClass(u + 4, c);
}
private void readInterfaces() {
int u = header;
int interfaceCount = readUnsignedShort(u + 6);
if (interfaceCount == 0) {
return;
}
interfaces = new String[interfaceCount];
u += 8;
char[] c = context.buffer;
for (int i = 0; i < interfaceCount; i++) {
interfaces[i] = readClass(u, c);
u += 2;
}
}
private void readClass() {
int version = readInt(items[1] - 7);
cv.visit(version, access, name, signature, superClass, interfaces);
}
private void readSourceAndDebugInfo() {
if (context.readDebugInfo() && (sourceFile != null || sourceDebug != null)) {
cv.visitSource(sourceFile, sourceDebug);
}
}
private void readOuterClass() {
if (enclosingMethod != null) {
cv.visitOuterClass(enclosingMethod.owner, enclosingMethod.name, enclosingMethod.desc);
}
}
private void readAnnotations(@Nonnegative int annotations) {
if (annotations != 0) {
char[] c = context.buffer;
for (int i = readUnsignedShort(annotations), v = annotations + 2; i > 0; i--) {
String desc = readUTF8(v, c);
@SuppressWarnings("ConstantConditions") AnnotationVisitor av = cv.visitAnnotation(desc);
v = annotationReader.readAnnotationValues(v + 2, c, true, av);
}
}
}
private void readInnerClasses(@Nonnegative int innerClasses) {
if (innerClasses != 0) {
int v = innerClasses + 2;
char[] c = context.buffer;
for (int i = readUnsignedShort(innerClasses); i > 0; i--) {
String name = readClass(v, c);
String outerName = readClass(v + 2, c);
String innerName = readUTF8(v + 4, c);
int access = readUnsignedShort(v + 6);
//noinspection ConstantConditions
cv.visitInnerClass(name, outerName, innerName, access);
v += 8;
}
}
}
private void readFieldsAndMethods() {
ClassVisitor cv = this.cv;
FieldReader fieldReader = new FieldReader(this);
int u = header + 8 + 2 * interfaces.length;
int fieldCount = readUnsignedShort(u);
u += 2;
for (int i = fieldCount; i > 0; i--) {
u = fieldReader.readField(cv, context, u);
}
MethodReader methodReader = new MethodReader(this, cv);
int methodCount = readUnsignedShort(u);
u += 2;
for (int i = methodCount; i > 0; i--) {
u = methodReader.readMethod(context, u);
}
}
private void readBootstrapMethods(@Nonnegative int u) {
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;
}
/**
* Returns the start index of the attribute_info structure of this class.
*/
@Nonnegative
int getAttributesStartIndex() {
// Skips the header.
int u = header + 8 + readUnsignedShort(header + 6) * 2;
// Skips fields and methods.
for (int i = readUnsignedShort(u); i > 0; i--) {
for (int j = readUnsignedShort(u + 8); j > 0; j--) {
u += 6 + readInt(u + 12);
}
u += 8;
}
u += 2;
for (int i = readUnsignedShort(u); i > 0; i--) {
for (int j = readUnsignedShort(u + 8); j > 0; j--) {
u += 6 + readInt(u + 12);
}
u += 8;
}
// The attribute_info structure starts just after the methods.
return u + 2;
}
}