src/jdk.jartool/share/classes/sun/tools/jar/FingerPrint.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2016, 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 sun.tools.jar;

 import jdk.internal.org.objectweb.asm.*;

 import java.io.IOException;
 import java.io.InputStream;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;

 /**
  * A FingerPrint is an abstract representation of a JarFile entry that contains
  * information to determine if the entry represents a class or a
  * resource, and whether two entries are identical.  If the FingerPrint represents
  * a class, it also contains information to (1) describe the public API;
  * (2) compare the public API of this class with another class;  (3) determine
  * whether or not it's a nested class and, if so, the name of the associated
  * outer class; and (4) for an canonically ordered set of classes determine
  * if the class versions are compatible.  A set of classes is canonically
  * ordered if the classes in the set have the same name, and the base class
  * precedes the versioned classes and if each versioned class with version
  * {@code n} precedes classes with versions {@code > n} for all versions
  * {@code n}.
  */
 final class FingerPrint {
     private static final MessageDigest MD;

     private final String basename;
     private final String entryName;
     private final int mrversion;

     private final byte[] sha1;
     private final ClassAttributes attrs;
     private final boolean isClassEntry;

     static {
         try {
             MD = MessageDigest.getInstance("SHA-1");
         } catch (NoSuchAlgorithmException x) {
             // log big problem?
             throw new RuntimeException(x);
         }
     }

     public FingerPrint(String basename, String entryName, int mrversion, byte[] bytes)
             throws IOException {
         this.basename = basename;
         this.entryName = entryName;
         this.mrversion = mrversion;
         if (isCafeBabe(bytes)) {
             isClassEntry = true;
             sha1 = sha1(bytes, 8);  // skip magic number and major/minor version
             attrs = getClassAttributes(bytes);
         } else {
             isClassEntry = false;
             sha1 = null;
             attrs = null;
         }
     }

     public boolean isClass() {
         return isClassEntry;
     }

     public boolean isNestedClass() {
         return attrs.nestedClass;
     }

     public boolean isPublicClass() {
         return attrs.publicClass;
     }

     public boolean isIdentical(FingerPrint that) {
         if (that == null) return false;
         if (this == that) return true;
         return isEqual(this.sha1, that.sha1);
     }

     public boolean isCompatibleVersion(FingerPrint that) {
         return attrs.version >= that.attrs.version;
     }

     public boolean isSameAPI(FingerPrint that) {
         if (that == null) return false;
         return attrs.equals(that.attrs);
     }

     public String basename() {
         return basename;
     }

     public String entryName() {
         return entryName;
     }

     public String className() {
         return attrs.name;
     }

     public int mrversion() {
         return mrversion;
     }

     public String outerClassName() {
         return attrs.outerClassName;
     }

     private byte[] sha1(byte[] entry) {
         MD.update(entry);
         return MD.digest();
     }

     private byte[] sha1(byte[] entry, int offset) {
         MD.update(entry, offset, entry.length - offset);
         return MD.digest();
     }

     private boolean isEqual(byte[] sha1_1, byte[] sha1_2) {
         return MessageDigest.isEqual(sha1_1, sha1_2);
     }

     private static final byte[] cafeBabe = {(byte)0xca, (byte)0xfe, (byte)0xba, (byte)0xbe};

     private boolean isCafeBabe(byte[] bytes) {
         if (bytes.length < 4) return false;
         for (int i = 0; i < 4; i++) {
             if (bytes[i] != cafeBabe[i]) {
                 return false;
             }
         }
         return true;
     }

     private ClassAttributes getClassAttributes(byte[] bytes) {
         ClassReader rdr = new ClassReader(bytes);
         ClassAttributes attrs = new ClassAttributes();
         rdr.accept(attrs, 0);
         return attrs;
     }

     private static final class Field {
         private final int access;
         private final String name;
         private final String desc;

         Field(int access, String name, String desc) {
             this.access = access;
             this.name = name;
             this.desc = desc;
         }

         @Override
         public boolean equals(Object that) {
             if (that == null) return false;
             if (this == that) return true;
             if (!(that instanceof Field)) return false;
             Field field = (Field)that;
             return (access == field.access) && name.equals(field.name)
                     && desc.equals(field.desc);
         }

         @Override
         public int hashCode() {
             int result = 17;
             result = 37 * result + access;
             result = 37 * result + name.hashCode();
             result = 37 * result + desc.hashCode();
             return result;
         }
     }

     private static final class Method {
         private final int access;
         private final String name;
         private final String desc;
         private final Set<String> exceptions;

         Method(int access, String name, String desc, Set<String> exceptions) {
             this.access = access;
             this.name = name;
             this.desc = desc;
             this.exceptions = exceptions;
         }

         @Override
         public boolean equals(Object that) {
             if (that == null) return false;
             if (this == that) return true;
             if (!(that instanceof Method)) return false;
             Method method = (Method)that;
             return (access == method.access) && name.equals(method.name)
                     && desc.equals(method.desc)
                     && exceptions.equals(method.exceptions);
         }

         @Override
         public int hashCode() {
             int result = 17;
             result = 37 * result + access;
             result = 37 * result + name.hashCode();
             result = 37 * result + desc.hashCode();
             result = 37 * result + exceptions.hashCode();
             return result;
         }
     }

     private static final class ClassAttributes extends ClassVisitor {
         private String name;
         private String outerClassName;
         private String superName;
         private int version;
         private int access;
         private boolean publicClass;
         private boolean nestedClass;
         private final Set<Field> fields = new HashSet<>();
         private final Set<Method> methods = new HashSet<>();

         public ClassAttributes() {
             super(Opcodes.ASM6);
         }

         private boolean isPublic(int access) {
             return ((access & Opcodes.ACC_PUBLIC) == Opcodes.ACC_PUBLIC)
                     || ((access & Opcodes.ACC_PROTECTED) == Opcodes.ACC_PROTECTED);
         }

         @Override
         public void visit(int version, int access, String name, String signature,
                           String superName, String[] interfaces) {
             this.version = version;
             this.access = access;
             this.name = name;
             this.nestedClass = name.contains("$");
             this.superName = superName;
             this.publicClass = isPublic(access);
         }

         @Override
         public void visitOuterClass(String owner, String name, String desc) {
             if (!this.nestedClass) return;
             this.outerClassName = owner;
         }

         @Override
         public void visitInnerClass(String name, String outerName, String innerName,
                                     int access) {
             if (!this.nestedClass) return;
             if (outerName == null) return;
             if (!this.name.equals(name)) return;
             if (this.outerClassName == null) this.outerClassName = outerName;
         }

         @Override
         public FieldVisitor visitField(int access, String name, String desc,
                                        String signature, Object value) {
             if (isPublic(access)) {
                 fields.add(new Field(access, name, desc));
             }
             return null;
         }

         @Override
         public MethodVisitor visitMethod(int access, String name, String desc,
                                          String signature, String[] exceptions) {
             if (isPublic(access)) {
                 Set<String> exceptionSet = new HashSet<>();
                 if (exceptions != null) {
                     for (String e : exceptions) {
                         exceptionSet.add(e);
                     }
                 }
                 // treat type descriptor as a proxy for signature because signature
                 // is usually null, need to strip off the return type though
                 int n;
                 if (desc != null && (n = desc.lastIndexOf(')')) != -1) {
                     desc = desc.substring(0, n + 1);
                     methods.add(new Method(access, name, desc, exceptionSet));
                 }
             }
             return null;
         }

         @Override
         public void visitEnd() {
             this.nestedClass = this.outerClassName != null;
         }

         @Override
         public boolean equals(Object that) {
             if (that == null) return false;
             if (this == that) return true;
             if (!(that instanceof ClassAttributes)) return false;
             ClassAttributes clsAttrs = (ClassAttributes)that;
             boolean superNameOkay = superName != null
                     ? superName.equals(clsAttrs.superName) : true;
             return access == clsAttrs.access
                     && superNameOkay
                     && fields.equals(clsAttrs.fields)
                     && methods.equals(clsAttrs.methods);
         }

         @Override
         public int hashCode() {
             int result = 17;
             result = 37 * result + access;
             result = 37 * result + superName != null ? superName.hashCode() : 0;
             result = 37 * result + fields.hashCode();
             result = 37 * result + methods.hashCode();
             return result;
         }
     }
 }
	/*
	* Copyright (c) 2016, 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 sun.tools.jar;

	import jdk.internal.org.objectweb.asm.*;

	import java.io.IOException;
	import java.io.InputStream;
	import java.security.MessageDigest;
	import java.security.NoSuchAlgorithmException;
	import java.util.HashMap;
	import java.util.HashSet;
	import java.util.Map;
	import java.util.Set;

	/**
	* A FingerPrint is an abstract representation of a JarFile entry that contains
	* information to determine if the entry represents a class or a
	* resource, and whether two entries are identical. If the FingerPrint represents
	* a class, it also contains information to (1) describe the public API;
	* (2) compare the public API of this class with another class; (3) determine
	* whether or not it's a nested class and, if so, the name of the associated
	* outer class; and (4) for an canonically ordered set of classes determine
	* if the class versions are compatible. A set of classes is canonically
	* ordered if the classes in the set have the same name, and the base class
	* precedes the versioned classes and if each versioned class with version
	* {@code n} precedes classes with versions {@code > n} for all versions
	* {@code n}.
	*/
	final class FingerPrint {
	private static final MessageDigest MD;

	private final String basename;
	private final String entryName;
	private final int mrversion;

	private final byte[] sha1;
	private final ClassAttributes attrs;
	private final boolean isClassEntry;

	static {
	try {
	MD = MessageDigest.getInstance("SHA-1");
	} catch (NoSuchAlgorithmException x) {
	// log big problem?
	throw new RuntimeException(x);
	}
	}

	public FingerPrint(String basename, String entryName, int mrversion, byte[] bytes)
	throws IOException {
	this.basename = basename;
	this.entryName = entryName;
	this.mrversion = mrversion;
	if (isCafeBabe(bytes)) {
	isClassEntry = true;
	sha1 = sha1(bytes, 8); // skip magic number and major/minor version
	attrs = getClassAttributes(bytes);
	} else {
	isClassEntry = false;
	sha1 = null;
	attrs = null;
	}
	}

	public boolean isClass() {
	return isClassEntry;
	}

	public boolean isNestedClass() {
	return attrs.nestedClass;
	}

	public boolean isPublicClass() {
	return attrs.publicClass;
	}

	public boolean isIdentical(FingerPrint that) {
	if (that == null) return false;
	if (this == that) return true;
	return isEqual(this.sha1, that.sha1);
	}

	public boolean isCompatibleVersion(FingerPrint that) {
	return attrs.version >= that.attrs.version;
	}

	public boolean isSameAPI(FingerPrint that) {
	if (that == null) return false;
	return attrs.equals(that.attrs);
	}

	public String basename() {
	return basename;
	}

	public String entryName() {
	return entryName;
	}

	public String className() {
	return attrs.name;
	}

	public int mrversion() {
	return mrversion;
	}

	public String outerClassName() {
	return attrs.outerClassName;
	}

	private byte[] sha1(byte[] entry) {
	MD.update(entry);
	return MD.digest();
	}

	private byte[] sha1(byte[] entry, int offset) {
	MD.update(entry, offset, entry.length - offset);
	return MD.digest();
	}

	private boolean isEqual(byte[] sha1_1, byte[] sha1_2) {
	return MessageDigest.isEqual(sha1_1, sha1_2);
	}

	private static final byte[] cafeBabe = {(byte)0xca, (byte)0xfe, (byte)0xba, (byte)0xbe};

	private boolean isCafeBabe(byte[] bytes) {
	if (bytes.length < 4) return false;
	for (int i = 0; i < 4; i++) {
	if (bytes[i] != cafeBabe[i]) {
	return false;
	}
	}
	return true;
	}

	private ClassAttributes getClassAttributes(byte[] bytes) {
	ClassReader rdr = new ClassReader(bytes);
	ClassAttributes attrs = new ClassAttributes();
	rdr.accept(attrs, 0);
	return attrs;
	}

	private static final class Field {
	private final int access;
	private final String name;
	private final String desc;

	Field(int access, String name, String desc) {
	this.access = access;
	this.name = name;
	this.desc = desc;
	}

	@Override
	public boolean equals(Object that) {
	if (that == null) return false;
	if (this == that) return true;
	if (!(that instanceof Field)) return false;
	Field field = (Field)that;
	return (access == field.access) && name.equals(field.name)
	&& desc.equals(field.desc);
	}

	@Override
	public int hashCode() {
	int result = 17;
	result = 37 * result + access;
	result = 37 * result + name.hashCode();
	result = 37 * result + desc.hashCode();
	return result;
	}
	}

	private static final class Method {
	private final int access;
	private final String name;
	private final String desc;
	private final Set<String> exceptions;

	Method(int access, String name, String desc, Set<String> exceptions) {
	this.access = access;
	this.name = name;
	this.desc = desc;
	this.exceptions = exceptions;
	}

	@Override
	public boolean equals(Object that) {
	if (that == null) return false;
	if (this == that) return true;
	if (!(that instanceof Method)) return false;
	Method method = (Method)that;
	return (access == method.access) && name.equals(method.name)
	&& desc.equals(method.desc)
	&& exceptions.equals(method.exceptions);
	}

	@Override
	public int hashCode() {
	int result = 17;
	result = 37 * result + access;
	result = 37 * result + name.hashCode();
	result = 37 * result + desc.hashCode();
	result = 37 * result + exceptions.hashCode();
	return result;
	}
	}

	private static final class ClassAttributes extends ClassVisitor {
	private String name;
	private String outerClassName;
	private String superName;
	private int version;
	private int access;
	private boolean publicClass;
	private boolean nestedClass;
	private final Set<Field> fields = new HashSet<>();
	private final Set<Method> methods = new HashSet<>();

	public ClassAttributes() {
	super(Opcodes.ASM6);
	}

	private boolean isPublic(int access) {
	return ((access & Opcodes.ACC_PUBLIC) == Opcodes.ACC_PUBLIC)
	\|\| ((access & Opcodes.ACC_PROTECTED) == Opcodes.ACC_PROTECTED);
	}

	@Override
	public void visit(int version, int access, String name, String signature,
	String superName, String[] interfaces) {
	this.version = version;
	this.access = access;
	this.name = name;
	this.nestedClass = name.contains("$");
	this.superName = superName;
	this.publicClass = isPublic(access);
	}

	@Override
	public void visitOuterClass(String owner, String name, String desc) {
	if (!this.nestedClass) return;
	this.outerClassName = owner;
	}

	@Override
	public void visitInnerClass(String name, String outerName, String innerName,
	int access) {
	if (!this.nestedClass) return;
	if (outerName == null) return;
	if (!this.name.equals(name)) return;
	if (this.outerClassName == null) this.outerClassName = outerName;
	}

	@Override
	public FieldVisitor visitField(int access, String name, String desc,
	String signature, Object value) {
	if (isPublic(access)) {
	fields.add(new Field(access, name, desc));
	}
	return null;
	}

	@Override
	public MethodVisitor visitMethod(int access, String name, String desc,
	String signature, String[] exceptions) {
	if (isPublic(access)) {
	Set<String> exceptionSet = new HashSet<>();
	if (exceptions != null) {
	for (String e : exceptions) {
	exceptionSet.add(e);
	}
	}
	// treat type descriptor as a proxy for signature because signature
	// is usually null, need to strip off the return type though
	int n;
	if (desc != null && (n = desc.lastIndexOf(')')) != -1) {
	desc = desc.substring(0, n + 1);
	methods.add(new Method(access, name, desc, exceptionSet));
	}
	}
	return null;
	}

	@Override
	public void visitEnd() {
	this.nestedClass = this.outerClassName != null;
	}

	@Override
	public boolean equals(Object that) {
	if (that == null) return false;
	if (this == that) return true;
	if (!(that instanceof ClassAttributes)) return false;
	ClassAttributes clsAttrs = (ClassAttributes)that;
	boolean superNameOkay = superName != null
	? superName.equals(clsAttrs.superName) : true;
	return access == clsAttrs.access
	&& superNameOkay
	&& fields.equals(clsAttrs.fields)
	&& methods.equals(clsAttrs.methods);
	}

	@Override
	public int hashCode() {
	int result = 17;
	result = 37 * result + access;
	result = 37 * result + superName != null ? superName.hashCode() : 0;
	result = 37 * result + fields.hashCode();
	result = 37 * result + methods.hashCode();
	return result;
	}
	}
	}