com.sun.tools.classfile.ClassFile Maven / Gradle / Ivy
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/*
* Copyright (c) 2007, 2013, 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.File;
import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import static com.sun.tools.classfile.AccessFlags.*;
/**
* See JVMS, section 4.2.
*
* 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 ClassFile {
public static ClassFile read(File file)
throws IOException, ConstantPoolException {
return read(file.toPath(), new Attribute.Factory());
}
public static ClassFile read(Path input)
throws IOException, ConstantPoolException {
return read(input, new Attribute.Factory());
}
public static ClassFile read(Path input, Attribute.Factory attributeFactory)
throws IOException, ConstantPoolException {
try (InputStream in = Files.newInputStream(input)) {
return new ClassFile(in, attributeFactory);
}
}
public static ClassFile read(File file, Attribute.Factory attributeFactory)
throws IOException, ConstantPoolException {
return read(file.toPath(), attributeFactory);
}
public static ClassFile read(InputStream in)
throws IOException, ConstantPoolException {
return new ClassFile(in, new Attribute.Factory());
}
public static ClassFile read(InputStream in, Attribute.Factory attributeFactory)
throws IOException, ConstantPoolException {
return new ClassFile(in, attributeFactory);
}
ClassFile(InputStream in, Attribute.Factory attributeFactory) throws IOException, ConstantPoolException {
ClassReader cr = new ClassReader(this, in, attributeFactory);
magic = cr.readInt();
minor_version = cr.readUnsignedShort();
major_version = cr.readUnsignedShort();
constant_pool = new ConstantPool(cr);
access_flags = new AccessFlags(cr);
this_class = cr.readUnsignedShort();
super_class = cr.readUnsignedShort();
int interfaces_count = cr.readUnsignedShort();
interfaces = new int[interfaces_count];
for (int i = 0; i < interfaces_count; i++)
interfaces[i] = cr.readUnsignedShort();
int fields_count = cr.readUnsignedShort();
fields = new Field[fields_count];
for (int i = 0; i < fields_count; i++)
fields[i] = new Field(cr);
int methods_count = cr.readUnsignedShort();
methods = new Method[methods_count];
for (int i = 0; i < methods_count; i++)
methods[i] = new Method(cr);
attributes = new Attributes(cr);
}
public ClassFile(int magic, int minor_version, int major_version,
ConstantPool constant_pool, AccessFlags access_flags,
int this_class, int super_class, int[] interfaces,
Field[] fields, Method[] methods, Attributes attributes) {
this.magic = magic;
this.minor_version = minor_version;
this.major_version = major_version;
this.constant_pool = constant_pool;
this.access_flags = access_flags;
this.this_class = this_class;
this.super_class = super_class;
this.interfaces = interfaces;
this.fields = fields;
this.methods = methods;
this.attributes = attributes;
}
public String getName() throws ConstantPoolException {
return constant_pool.getClassInfo(this_class).getName();
}
public String getSuperclassName() throws ConstantPoolException {
return constant_pool.getClassInfo(super_class).getName();
}
public String getInterfaceName(int i) throws ConstantPoolException {
return constant_pool.getClassInfo(interfaces[i]).getName();
}
public Attribute getAttribute(String name) {
return attributes.get(name);
}
public boolean isClass() {
return !isInterface();
}
public boolean isInterface() {
return access_flags.is(ACC_INTERFACE);
}
public int byteLength() {
return 4 + // magic
2 + // minor
2 + // major
constant_pool.byteLength() +
2 + // access flags
2 + // this_class
2 + // super_class
byteLength(interfaces) +
byteLength(fields) +
byteLength(methods) +
attributes.byteLength();
}
private int byteLength(int[] indices) {
return 2 + 2 * indices.length;
}
private int byteLength(Field[] fields) {
int length = 2;
for (Field f: fields)
length += f.byteLength();
return length;
}
private int byteLength(Method[] methods) {
int length = 2;
for (Method m: methods)
length += m.byteLength();
return length;
}
public final int magic;
public final int minor_version;
public final int major_version;
public final ConstantPool constant_pool;
public final AccessFlags access_flags;
public final int this_class;
public final int super_class;
public final int[] interfaces;
public final Field[] fields;
public final Method[] methods;
public final Attributes attributes;
}