/** Parses a {@code bootstrap} attribute. */
private Attribute bootstrap(DirectClassFile cf, int offset, int length, ParseObserver observer) {
if (length < 2) {
throwBadLength(2);
}
ByteArray bytes = cf.getBytes();
ConstantPool pool = cf.getConstantPool();
int count = bytes.getUnsignedShort(offset);
BootstrapMethodList list =
parseBootstrapMethods(
bytes.slice(offset + 2, offset + length), cf.getConstantPool(), observer, count);
if (observer != null) {
// observer.parsed(bytes, offset, 2, "source: " + cst);
}
AttBootstrapMethods attBootstrapMethods = new AttBootstrapMethods(list);
// -6 for header (cf. 4.7.21)
offset += attBootstrapMethods.byteLength() - 6;
return attBootstrapMethods;
}
/** Parses an {@code InnerClasses} attribute. */
private Attribute innerClasses(
DirectClassFile cf, int offset, int length, ParseObserver observer) {
if (length < 2) {
return throwSeverelyTruncated();
}
ByteArray bytes = cf.getBytes();
ConstantPool pool = cf.getConstantPool();
int count = bytes.getUnsignedShort(offset); // number_of_classes
if (observer != null) {
observer.parsed(bytes, offset, 2, "number_of_classes: " + Hex.u2(count));
}
offset += 2;
length -= 2;
if (length != (count * 8)) {
throwBadLength((count * 8) + 2);
}
InnerClassList list = new InnerClassList(count);
for (int i = 0; i < count; i++) {
int innerClassIdx = bytes.getUnsignedShort(offset);
int outerClassIdx = bytes.getUnsignedShort(offset + 2);
int nameIdx = bytes.getUnsignedShort(offset + 4);
int accessFlags = bytes.getUnsignedShort(offset + 6);
CstType innerClass = (CstType) pool.get(innerClassIdx);
CstType outerClass = (CstType) pool.get0Ok(outerClassIdx);
CstString name = (CstString) pool.get0Ok(nameIdx);
list.set(i, innerClass, outerClass, name, accessFlags);
if (observer != null) {
observer.parsed(
bytes, offset, 2, "inner_class: " + DirectClassFile.stringOrNone(innerClass));
observer.parsed(
bytes, offset + 2, 2, " outer_class: " + DirectClassFile.stringOrNone(outerClass));
observer.parsed(bytes, offset + 4, 2, " name: " + DirectClassFile.stringOrNone(name));
observer.parsed(
bytes, offset + 6, 2, " access_flags: " + AccessFlags.innerClassString(accessFlags));
}
offset += 8;
}
list.setImmutable();
return new AttInnerClasses(list);
}
/** Parses a {@code SourceFile} attribute. */
private Attribute sourceFile(DirectClassFile cf, int offset, int length, ParseObserver observer) {
if (length != 2) {
throwBadLength(2);
}
ByteArray bytes = cf.getBytes();
ConstantPool pool = cf.getConstantPool();
int idx = bytes.getUnsignedShort(offset);
CstString cst = (CstString) pool.get(idx);
Attribute result = new AttSourceFile(cst);
if (observer != null) {
observer.parsed(bytes, offset, 2, "source: " + cst);
}
return result;
}
/** Parses a {@code LocalVariableTypeTable} attribute. */
private Attribute localVariableTypeTable(
DirectClassFile cf, int offset, int length, ParseObserver observer) {
if (length < 2) {
return throwSeverelyTruncated();
}
ByteArray bytes = cf.getBytes();
int count = bytes.getUnsignedShort(offset);
if (observer != null) {
observer.parsed(bytes, offset, 2, "local_variable_type_table_length: " + Hex.u2(count));
}
LocalVariableList list =
parseLocalVariables(
bytes.slice(offset + 2, offset + length), cf.getConstantPool(), observer, count, true);
return new AttLocalVariableTypeTable(list);
}
/** Parses a {@code ConstantValue} attribute. */
private Attribute constantValue(
DirectClassFile cf, int offset, int length, ParseObserver observer) {
if (length != 2) {
return throwBadLength(2);
}
ByteArray bytes = cf.getBytes();
ConstantPool pool = cf.getConstantPool();
int idx = bytes.getUnsignedShort(offset);
TypedConstant cst = (TypedConstant) pool.get(idx);
Attribute result = new AttConstantValue(cst);
if (observer != null) {
observer.parsed(bytes, offset, 2, "value: " + cst);
}
return result;
}
/** Parses an {@code EnclosingMethod} attribute. */
private Attribute enclosingMethod(
DirectClassFile cf, int offset, int length, ParseObserver observer) {
if (length != 4) {
throwBadLength(4);
}
ByteArray bytes = cf.getBytes();
ConstantPool pool = cf.getConstantPool();
int idx = bytes.getUnsignedShort(offset);
CstType type = (CstType) pool.get(idx);
idx = bytes.getUnsignedShort(offset + 2);
CstNat method = (CstNat) pool.get0Ok(idx);
Attribute result = new AttEnclosingMethod(type, method);
if (observer != null) {
observer.parsed(bytes, offset, 2, "class: " + type);
observer.parsed(bytes, offset + 2, 2, "method: " + DirectClassFile.stringOrNone(method));
}
return result;
}
/** Parses a {@code Code} attribute. */
private Attribute code(DirectClassFile cf, int offset, int length, ParseObserver observer) {
if (length < 12) {
return throwSeverelyTruncated();
}
ByteArray bytes = cf.getBytes();
ConstantPool pool = cf.getConstantPool();
int maxStack = bytes.getUnsignedShort(offset); // u2 max_stack
int maxLocals = bytes.getUnsignedShort(offset + 2); // u2 max_locals
int codeLength = bytes.getInt(offset + 4); // u4 code_length
int origOffset = offset;
if (observer != null) {
observer.parsed(bytes, offset, 2, "max_stack: " + Hex.u2(maxStack));
observer.parsed(bytes, offset + 2, 2, "max_locals: " + Hex.u2(maxLocals));
observer.parsed(bytes, offset + 4, 4, "code_length: " + Hex.u4(codeLength));
}
offset += 8;
length -= 8;
if (length < (codeLength + 4)) {
return throwTruncated();
}
int codeOffset = offset;
offset += codeLength;
length -= codeLength;
BytecodeArray code = new BytecodeArray(bytes.slice(codeOffset, codeOffset + codeLength), pool);
if (observer != null) {
code.forEach(new CodeObserver(code.getBytes(), observer));
}
// u2 exception_table_length
int exceptionTableLength = bytes.getUnsignedShort(offset);
ByteCatchList catches =
(exceptionTableLength == 0) ? ByteCatchList.EMPTY : new ByteCatchList(exceptionTableLength);
if (observer != null) {
observer.parsed(bytes, offset, 2, "exception_table_length: " + Hex.u2(exceptionTableLength));
}
offset += 2;
length -= 2;
if (length < (exceptionTableLength * 8 + 2)) {
return throwTruncated();
}
for (int i = 0; i < exceptionTableLength; i++) {
if (observer != null) {
observer.changeIndent(1);
}
int startPc = bytes.getUnsignedShort(offset);
int endPc = bytes.getUnsignedShort(offset + 2);
int handlerPc = bytes.getUnsignedShort(offset + 4);
int catchTypeIdx = bytes.getUnsignedShort(offset + 6);
CstType catchType = (CstType) pool.get0Ok(catchTypeIdx);
catches.set(i, startPc, endPc, handlerPc, catchType);
if (observer != null) {
observer.parsed(
bytes,
offset,
8,
Hex.u2(startPc)
+ ".."
+ Hex.u2(endPc)
+ " -> "
+ Hex.u2(handlerPc)
+ " "
+ ((catchType == null) ? "<any>" : catchType.toHuman()));
}
offset += 8;
length -= 8;
if (observer != null) {
observer.changeIndent(-1);
}
}
catches.setImmutable();
AttributeListParser parser = new AttributeListParser(cf, CTX_CODE, offset, this);
parser.setObserver(observer);
StdAttributeList attributes = parser.getList();
attributes.setImmutable();
int attributeByteCount = parser.getEndOffset() - offset;
if (attributeByteCount != length) {
return throwBadLength(attributeByteCount + (offset - origOffset));
}
return new AttCode(maxStack, maxLocals, code, catches, attributes);
}