📄 classwriter.java
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public MethodVisitor visitMethod(
final int access,
final String name,
final String desc,
final String signature,
final String[] exceptions)
{
return new MethodWriter(this,
access,
name,
desc,
signature,
exceptions,
computeMaxs,
computeFrames);
}
public void visitEnd() {
}
// ------------------------------------------------------------------------
// Other public methods
// ------------------------------------------------------------------------
/**
* Returns the bytecode of the class that was build with this class writer.
*
* @return the bytecode of the class that was build with this class writer.
*/
public byte[] toByteArray() {
// computes the real size of the bytecode of this class
int size = 24 + 2 * interfaceCount;
int nbFields = 0;
FieldWriter fb = firstField;
while (fb != null) {
++nbFields;
size += fb.getSize();
fb = fb.next;
}
int nbMethods = 0;
MethodWriter mb = firstMethod;
while (mb != null) {
++nbMethods;
size += mb.getSize();
mb = mb.next;
}
int attributeCount = 0;
if (signature != 0) {
++attributeCount;
size += 8;
newUTF8("Signature");
}
if (sourceFile != 0) {
++attributeCount;
size += 8;
newUTF8("SourceFile");
}
if (sourceDebug != null) {
++attributeCount;
size += sourceDebug.length + 4;
newUTF8("SourceDebugExtension");
}
if (enclosingMethodOwner != 0) {
++attributeCount;
size += 10;
newUTF8("EnclosingMethod");
}
if ((access & Opcodes.ACC_DEPRECATED) != 0) {
++attributeCount;
size += 6;
newUTF8("Deprecated");
}
if ((access & Opcodes.ACC_SYNTHETIC) != 0
&& (version & 0xffff) < Opcodes.V1_5)
{
++attributeCount;
size += 6;
newUTF8("Synthetic");
}
if (innerClasses != null) {
++attributeCount;
size += 8 + innerClasses.length;
newUTF8("InnerClasses");
}
if (anns != null) {
++attributeCount;
size += 8 + anns.getSize();
newUTF8("RuntimeVisibleAnnotations");
}
if (ianns != null) {
++attributeCount;
size += 8 + ianns.getSize();
newUTF8("RuntimeInvisibleAnnotations");
}
if (attrs != null) {
attributeCount += attrs.getCount();
size += attrs.getSize(this, null, 0, -1, -1);
}
size += pool.length;
// allocates a byte vector of this size, in order to avoid unnecessary
// arraycopy operations in the ByteVector.enlarge() method
ByteVector out = new ByteVector(size);
out.putInt(0xCAFEBABE).putInt(version);
out.putShort(index).putByteArray(pool.data, 0, pool.length);
out.putShort(access).putShort(name).putShort(superName);
out.putShort(interfaceCount);
for (int i = 0; i < interfaceCount; ++i) {
out.putShort(interfaces[i]);
}
out.putShort(nbFields);
fb = firstField;
while (fb != null) {
fb.put(out);
fb = fb.next;
}
out.putShort(nbMethods);
mb = firstMethod;
while (mb != null) {
mb.put(out);
mb = mb.next;
}
out.putShort(attributeCount);
if (signature != 0) {
out.putShort(newUTF8("Signature")).putInt(2).putShort(signature);
}
if (sourceFile != 0) {
out.putShort(newUTF8("SourceFile")).putInt(2).putShort(sourceFile);
}
if (sourceDebug != null) {
int len = sourceDebug.length - 2;
out.putShort(newUTF8("SourceDebugExtension")).putInt(len);
out.putByteArray(sourceDebug.data, 2, len);
}
if (enclosingMethodOwner != 0) {
out.putShort(newUTF8("EnclosingMethod")).putInt(4);
out.putShort(enclosingMethodOwner).putShort(enclosingMethod);
}
if ((access & Opcodes.ACC_DEPRECATED) != 0) {
out.putShort(newUTF8("Deprecated")).putInt(0);
}
if ((access & Opcodes.ACC_SYNTHETIC) != 0
&& (version & 0xffff) < Opcodes.V1_5)
{
out.putShort(newUTF8("Synthetic")).putInt(0);
}
if (innerClasses != null) {
out.putShort(newUTF8("InnerClasses"));
out.putInt(innerClasses.length + 2).putShort(innerClassesCount);
out.putByteArray(innerClasses.data, 0, innerClasses.length);
}
if (anns != null) {
out.putShort(newUTF8("RuntimeVisibleAnnotations"));
anns.put(out);
}
if (ianns != null) {
out.putShort(newUTF8("RuntimeInvisibleAnnotations"));
ianns.put(out);
}
if (attrs != null) {
attrs.put(this, null, 0, -1, -1, out);
}
if (invalidFrames) {
ClassWriter cw = new ClassWriter(COMPUTE_FRAMES);
new ClassReader(out.data).accept(cw, ClassReader.SKIP_FRAMES);
return cw.toByteArray();
}
return out.data;
}
// ------------------------------------------------------------------------
// Utility methods: constant pool management
// ------------------------------------------------------------------------
/**
* Adds a number or string constant to the constant pool of the class being
* build. Does nothing if the constant pool already contains a similar item.
*
* @param cst the value of the constant to be added to the constant pool.
* This parameter must be an {@link Integer}, a {@link Float}, a
* {@link Long}, a {@link Double}, a {@link String} or a
* {@link Type}.
* @return a new or already existing constant item with the given value.
*/
Item newConstItem(final Object cst) {
if (cst instanceof Integer) {
int val = ((Integer) cst).intValue();
return newInteger(val);
} else if (cst instanceof Byte) {
int val = ((Byte) cst).intValue();
return newInteger(val);
} else if (cst instanceof Character) {
int val = ((Character) cst).charValue();
return newInteger(val);
} else if (cst instanceof Short) {
int val = ((Short) cst).intValue();
return newInteger(val);
} else if (cst instanceof Boolean) {
int val = ((Boolean) cst).booleanValue() ? 1 : 0;
return newInteger(val);
} else if (cst instanceof Float) {
float val = ((Float) cst).floatValue();
return newFloat(val);
} else if (cst instanceof Long) {
long val = ((Long) cst).longValue();
return newLong(val);
} else if (cst instanceof Double) {
double val = ((Double) cst).doubleValue();
return newDouble(val);
} else if (cst instanceof String) {
return newString((String) cst);
} else if (cst instanceof Type) {
Type t = (Type) cst;
return newClassItem(t.getSort() == Type.OBJECT
? t.getInternalName()
: t.getDescriptor());
} else {
throw new IllegalArgumentException("value " + cst);
}
}
/**
* Adds a number or string constant to the constant pool of the class being
* build. Does nothing if the constant pool already contains a similar item.
* <i>This method is intended for {@link Attribute} sub classes, and is
* normally not needed by class generators or adapters.</i>
*
* @param cst the value of the constant to be added to the constant pool.
* This parameter must be an {@link Integer}, a {@link Float}, a
* {@link Long}, a {@link Double} or a {@link String}.
* @return the index of a new or already existing constant item with the
* given value.
*/
public int newConst(final Object cst) {
return newConstItem(cst).index;
}
/**
* Adds an UTF8 string to the constant pool of the class being build. Does
* nothing if the constant pool already contains a similar item. <i>This
* method is intended for {@link Attribute} sub classes, and is normally not
* needed by class generators or adapters.</i>
*
* @param value the String value.
* @return the index of a new or already existing UTF8 item.
*/
public int newUTF8(final String value) {
key.set(UTF8, value, null, null);
Item result = get(key);
if (result == null) {
pool.putByte(UTF8).putUTF8(value);
result = new Item(index++, key);
put(result);
}
return result.index;
}
/**
* Adds a class reference to the constant pool of the class being build.
* Does nothing if the constant pool already contains a similar item.
* <i>This method is intended for {@link Attribute} sub classes, and is
* normally not needed by class generators or adapters.</i>
*
* @param value the internal name of the class.
* @return a new or already existing class reference item.
*/
Item newClassItem(final String value) {
key2.set(CLASS, value, null, null);
Item result = get(key2);
if (result == null) {
pool.put12(CLASS, newUTF8(value));
result = new Item(index++, key2);
put(result);
}
return result;
}
/**
* Adds a class reference to the constant pool of the class being build.
* Does nothing if the constant pool already contains a similar item.
* <i>This method is intended for {@link Attribute} sub classes, and is
* normally not needed by class generators or adapters.</i>
*
* @param value the internal name of the class.
* @return the index of a new or already existing class reference item.
*/
public int newClass(final String value) {
return newClassItem(value).index;
}
/**
* Adds a field reference to the constant pool of the class being build.
* Does nothing if the constant pool already contains a similar item.
*
* @param owner the internal name of the field's owner class.
* @param name the field's name.
* @param desc the field's descriptor.
* @return a new or already existing field reference item.
*/
Item newFieldItem(final String owner, final String name, final String desc)
{
key3.set(FIELD, owner, name, desc);
Item result = get(key3);
if (result == null) {
put122(FIELD, newClass(owner), newNameType(name, desc));
result = new Item(index++, key3);
put(result);
}
return result;
}
/**
* Adds a field reference to the constant pool of the class being build.
* Does nothing if the constant pool already contains a similar item.
* <i>This method is intended for {@link Attribute} sub classes, and is
* normally not needed by class generators or adapters.</i>
*
* @param owner the internal name of the field's owner class.
* @param name the field's name.
* @param desc the field's descriptor.
* @return the index of a new or already existing field reference item.
*/
public int newField(final String owner, final String name, final String desc)
{
return newFieldItem(owner, name, desc).index;
}
/**
* Adds a method reference to the constant pool of the class being build.
* Does nothing if the constant pool already contains a similar item.
*
* @param owner the internal name of the method's owner class.
* @param name the method's name.
* @param desc the method's descriptor.
* @param itf <tt>true</tt> if <tt>owner</tt> is an interface.
* @return a new or already existing method reference item.
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