com.sun.tools.classfile.StackMapTable_attribute Maven / Gradle / Ivy
Show all versions of javac Show documentation
/*
* Copyright (c) 2007, 2009, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.sun.tools.classfile;
import java.io.IOException;
/**
* See JVMS, section 4.8.4.
*
* This is NOT part of any supported API.
* If you write code that depends on this, you do so at your own risk.
* This code and its internal interfaces are subject to change or
* deletion without notice.
*/
public class StackMapTable_attribute extends Attribute {
static class InvalidStackMap extends AttributeException {
private static final long serialVersionUID = -5659038410855089780L;
InvalidStackMap(String msg) {
super(msg);
}
}
StackMapTable_attribute(ClassReader cr, int name_index, int length)
throws IOException, InvalidStackMap {
super(name_index, length);
number_of_entries = cr.readUnsignedShort();
entries = new stack_map_frame[number_of_entries];
for (int i = 0; i < number_of_entries; i++)
entries[i] = stack_map_frame.read(cr);
}
public StackMapTable_attribute(ConstantPool constant_pool, stack_map_frame[] entries)
throws ConstantPoolException {
this(constant_pool.getUTF8Index(Attribute.StackMapTable), entries);
}
public StackMapTable_attribute(int name_index, stack_map_frame[] entries) {
super(name_index, length(entries));
this.number_of_entries = entries.length;
this.entries = entries;
}
public R accept(Visitor visitor, D data) {
return visitor.visitStackMapTable(this, data);
}
static int length(stack_map_frame[] entries) {
int n = 2;
for (stack_map_frame entry: entries)
n += entry.length();
return n;
}
public final int number_of_entries;
public final stack_map_frame entries[];
public static abstract class stack_map_frame {
static stack_map_frame read(ClassReader cr)
throws IOException, InvalidStackMap {
int frame_type = cr.readUnsignedByte();
if (frame_type <= 63)
return new same_frame(frame_type);
else if (frame_type <= 127)
return new same_locals_1_stack_item_frame(frame_type, cr);
else if (frame_type <= 246)
throw new Error("unknown frame_type " + frame_type);
else if (frame_type == 247)
return new same_locals_1_stack_item_frame_extended(frame_type, cr);
else if (frame_type <= 250)
return new chop_frame(frame_type, cr);
else if (frame_type == 251)
return new same_frame_extended(frame_type, cr);
else if (frame_type <= 254)
return new append_frame(frame_type, cr);
else
return new full_frame(frame_type, cr);
}
protected stack_map_frame(int frame_type) {
this.frame_type = frame_type;
}
public int length() {
return 1;
}
public abstract int getOffsetDelta();
public abstract R accept(Visitor visitor, D data);
public final int frame_type;
public static interface Visitor {
R visit_same_frame(same_frame frame, P p);
R visit_same_locals_1_stack_item_frame(same_locals_1_stack_item_frame frame, P p);
R visit_same_locals_1_stack_item_frame_extended(same_locals_1_stack_item_frame_extended frame, P p);
R visit_chop_frame(chop_frame frame, P p);
R visit_same_frame_extended(same_frame_extended frame, P p);
R visit_append_frame(append_frame frame, P p);
R visit_full_frame(full_frame frame, P p);
}
}
public static class same_frame extends stack_map_frame {
same_frame(int frame_type) {
super(frame_type);
}
public R accept(Visitor visitor, D data) {
return visitor.visit_same_frame(this, data);
}
public int getOffsetDelta() {
return frame_type;
}
}
public static class same_locals_1_stack_item_frame extends stack_map_frame {
same_locals_1_stack_item_frame(int frame_type, ClassReader cr)
throws IOException, InvalidStackMap {
super(frame_type);
stack = new verification_type_info[1];
stack[0] = verification_type_info.read(cr);
}
@Override
public int length() {
return super.length() + stack[0].length();
}
public R accept(Visitor visitor, D data) {
return visitor.visit_same_locals_1_stack_item_frame(this, data);
}
public int getOffsetDelta() {
return frame_type - 64;
}
public final verification_type_info[] stack;
}
public static class same_locals_1_stack_item_frame_extended extends stack_map_frame {
same_locals_1_stack_item_frame_extended(int frame_type, ClassReader cr)
throws IOException, InvalidStackMap {
super(frame_type);
offset_delta = cr.readUnsignedShort();
stack = new verification_type_info[1];
stack[0] = verification_type_info.read(cr);
}
@Override
public int length() {
return super.length() + 2 + stack[0].length();
}
public R accept(Visitor visitor, D data) {
return visitor.visit_same_locals_1_stack_item_frame_extended(this, data);
}
public int getOffsetDelta() {
return offset_delta;
}
public final int offset_delta;
public final verification_type_info[] stack;
}
public static class chop_frame extends stack_map_frame {
chop_frame(int frame_type, ClassReader cr) throws IOException {
super(frame_type);
offset_delta = cr.readUnsignedShort();
}
@Override
public int length() {
return super.length() + 2;
}
public R accept(Visitor visitor, D data) {
return visitor.visit_chop_frame(this, data);
}
public int getOffsetDelta() {
return offset_delta;
}
public final int offset_delta;
}
public static class same_frame_extended extends stack_map_frame {
same_frame_extended(int frame_type, ClassReader cr) throws IOException {
super(frame_type);
offset_delta = cr.readUnsignedShort();
}
@Override
public int length() {
return super.length() + 2;
}
public R accept(Visitor visitor, D data) {
return visitor.visit_same_frame_extended(this, data);
}
public int getOffsetDelta() {
return offset_delta;
}
public final int offset_delta;
}
public static class append_frame extends stack_map_frame {
append_frame(int frame_type, ClassReader cr)
throws IOException, InvalidStackMap {
super(frame_type);
offset_delta = cr.readUnsignedShort();
locals = new verification_type_info[frame_type - 251];
for (int i = 0; i < locals.length; i++)
locals[i] = verification_type_info.read(cr);
}
@Override
public int length() {
int n = super.length() + 2;
for (verification_type_info local: locals)
n += local.length();
return n;
}
public R accept(Visitor visitor, D data) {
return visitor.visit_append_frame(this, data);
}
public int getOffsetDelta() {
return offset_delta;
}
public final int offset_delta;
public final verification_type_info[] locals;
}
public static class full_frame extends stack_map_frame {
full_frame(int frame_type, ClassReader cr)
throws IOException, InvalidStackMap {
super(frame_type);
offset_delta = cr.readUnsignedShort();
number_of_locals = cr.readUnsignedShort();
locals = new verification_type_info[number_of_locals];
for (int i = 0; i < locals.length; i++)
locals[i] = verification_type_info.read(cr);
number_of_stack_items = cr.readUnsignedShort();
stack = new verification_type_info[number_of_stack_items];
for (int i = 0; i < stack.length; i++)
stack[i] = verification_type_info.read(cr);
}
@Override
public int length() {
int n = super.length() + 2;
for (verification_type_info local: locals)
n += local.length();
n += 2;
for (verification_type_info item: stack)
n += item.length();
return n;
}
public R accept(Visitor visitor, D data) {
return visitor.visit_full_frame(this, data);
}
public int getOffsetDelta() {
return offset_delta;
}
public final int offset_delta;
public final int number_of_locals;
public final verification_type_info[] locals;
public final int number_of_stack_items;
public final verification_type_info[] stack;
}
public static class verification_type_info {
public static final int ITEM_Top = 0;
public static final int ITEM_Integer = 1;
public static final int ITEM_Float = 2;
public static final int ITEM_Long = 4;
public static final int ITEM_Double = 3;
public static final int ITEM_Null = 5;
public static final int ITEM_UninitializedThis = 6;
public static final int ITEM_Object = 7;
public static final int ITEM_Uninitialized = 8;
static verification_type_info read(ClassReader cr)
throws IOException, InvalidStackMap {
int tag = cr.readUnsignedByte();
switch (tag) {
case ITEM_Top:
case ITEM_Integer:
case ITEM_Float:
case ITEM_Long:
case ITEM_Double:
case ITEM_Null:
case ITEM_UninitializedThis:
return new verification_type_info(tag);
case ITEM_Object:
return new Object_variable_info(cr);
case ITEM_Uninitialized:
return new Uninitialized_variable_info(cr);
default:
throw new InvalidStackMap("unrecognized verification_type_info tag");
}
}
protected verification_type_info(int tag) {
this.tag = tag;
}
public int length() {
return 1;
}
public final int tag;
}
public static class Object_variable_info extends verification_type_info {
Object_variable_info(ClassReader cr) throws IOException {
super(ITEM_Object);
cpool_index = cr.readUnsignedShort();
}
@Override
public int length() {
return super.length() + 2;
}
public final int cpool_index;
}
public static class Uninitialized_variable_info extends verification_type_info {
Uninitialized_variable_info(ClassReader cr) throws IOException {
super(ITEM_Uninitialized);
offset = cr.readUnsignedShort();
}
@Override
public int length() {
return super.length() + 2;
}
public final int offset;
}
}