duke@1: /*
ohair@554:  * Copyright (c) 1999, 2008, Oracle and/or its affiliates. All rights reserved.
duke@1:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@1:  *
duke@1:  * This code is free software; you can redistribute it and/or modify it
duke@1:  * under the terms of the GNU General Public License version 2 only, as
ohair@554:  * published by the Free Software Foundation.  Oracle designates this
duke@1:  * particular file as subject to the "Classpath" exception as provided
ohair@554:  * by Oracle in the LICENSE file that accompanied this code.
duke@1:  *
duke@1:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@1:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@1:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@1:  * version 2 for more details (a copy is included in the LICENSE file that
duke@1:  * accompanied this code).
duke@1:  *
duke@1:  * You should have received a copy of the GNU General Public License version
duke@1:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@1:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@1:  *
ohair@554:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
ohair@554:  * or visit www.oracle.com if you need additional information or have any
ohair@554:  * questions.
duke@1:  */
duke@1: 
duke@1: package com.sun.tools.javac.util;
duke@1: 
jjg@113: /** An abstraction for internal compiler strings. They are stored in
jjg@113:  *  Utf8 format. Names are stored in a Name.Table, and are unique within
jjg@113:  *  that table.
duke@1:  *
jjg@581:  *  <p><b>This is NOT part of any supported API.
jjg@581:  *  If you write code that depends on this, you do so at your own risk.
duke@1:  *  This code and its internal interfaces are subject to change or
duke@1:  *  deletion without notice.</b>
duke@1:  */
jjg@113: public abstract class Name implements javax.lang.model.element.Name {
duke@1: 
jjg@113:     public final Table table;
duke@1: 
jjg@113:     protected Name(Table table) {
jjg@113:         this.table = table;
duke@1:     }
duke@1: 
jjg@113:     /**
jjg@113:      * @inheritDoc
duke@1:      */
jjg@113:     public boolean contentEquals(CharSequence cs) {
jjg@113:         return toString().equals(cs.toString());
duke@1:     }
duke@1: 
jjg@113:     /**
jjg@113:      * @inheritDoc
duke@1:      */
duke@1:     public int length() {
duke@1:         return toString().length();
duke@1:     }
duke@1: 
jjg@113:     /**
jjg@113:      * @inheritDoc
duke@1:      */
jjg@113:     public char charAt(int index) {
jjg@113:         return toString().charAt(index);
duke@1:     }
duke@1: 
jjg@113:     /**
jjg@113:      * @inheritDoc
duke@1:      */
jjg@113:     public CharSequence subSequence(int start, int end) {
jjg@113:         return toString().subSequence(start, end);
jjg@113:     }
jjg@113: 
jjg@113:     /** Return the concatenation of this name and name `n'.
jjg@113:      */
jjg@113:     public Name append(Name n) {
jjg@113:         int len = getByteLength();
jjg@113:         byte[] bs = new byte[len + n.getByteLength()];
jjg@113:         getBytes(bs, 0);
jjg@113:         n.getBytes(bs, len);
jjg@113:         return table.fromUtf(bs, 0, bs.length);
jjg@113:     }
jjg@113: 
jjg@113:     /** Return the concatenation of this name, the given ASCII
jjg@113:      *  character, and name `n'.
jjg@113:      */
jjg@113:     public Name append(char c, Name n) {
jjg@113:         int len = getByteLength();
jjg@113:         byte[] bs = new byte[len + 1 + n.getByteLength()];
jjg@113:         getBytes(bs, 0);
jjg@113:         bs[len] = (byte) c;
jjg@113:         n.getBytes(bs, len+1);
jjg@113:         return table.fromUtf(bs, 0, bs.length);
jjg@113:     }
jjg@113: 
jjg@113:     /** An arbitrary but consistent complete order among all Names.
jjg@113:      */
jjg@113:     public int compareTo(Name other) {
jjg@113:         return other.getIndex() - this.getIndex();
jjg@113:     }
jjg@113: 
jjg@113:     /** Return true if this is the empty name.
jjg@113:      */
jjg@113:     public boolean isEmpty() {
jjg@113:         return getByteLength() == 0;
duke@1:     }
duke@1: 
duke@1:     /** Returns last occurrence of byte b in this name, -1 if not found.
duke@1:      */
duke@1:     public int lastIndexOf(byte b) {
jjg@113:         byte[] bytes = getByteArray();
jjg@113:         int offset = getByteOffset();
jjg@113:         int i = getByteLength() - 1;
jjg@113:         while (i >= 0 && bytes[offset + i] != b) i--;
duke@1:         return i;
duke@1:     }
duke@1: 
duke@1:     /** Does this name start with prefix?
duke@1:      */
duke@1:     public boolean startsWith(Name prefix) {
jjg@113:         byte[] thisBytes = this.getByteArray();
jjg@113:         int thisOffset   = this.getByteOffset();
jjg@113:         int thisLength   = this.getByteLength();
jjg@113:         byte[] prefixBytes = prefix.getByteArray();
jjg@113:         int prefixOffset   = prefix.getByteOffset();
jjg@113:         int prefixLength   = prefix.getByteLength();
jjg@113: 
duke@1:         int i = 0;
jjg@113:         while (i < prefixLength &&
jjg@113:                i < thisLength &&
jjg@113:                thisBytes[thisOffset + i] == prefixBytes[prefixOffset + i])
duke@1:             i++;
jjg@113:         return i == prefixLength;
duke@1:     }
duke@1: 
duke@1:     /** Returns the sub-name starting at position start, up to and
duke@1:      *  excluding position end.
duke@1:      */
duke@1:     public Name subName(int start, int end) {
duke@1:         if (end < start) end = start;
jjg@113:         return table.fromUtf(getByteArray(), getByteOffset() + start, end - start);
duke@1:     }
duke@1: 
jjg@113:     /** Return the string representation of this name.
duke@1:      */
jjg@113:     public String toString() {
jjg@113:         return Convert.utf2string(getByteArray(), getByteOffset(), getByteLength());
duke@1:     }
duke@1: 
jjg@113:     /** Return the Utf8 representation of this name.
duke@1:      */
jjg@113:     public byte[] toUtf() {
jjg@113:         byte[] bs = new byte[getByteLength()];
duke@1:         getBytes(bs, 0);
jjg@113:         return bs;
duke@1:     }
duke@1: 
jjg@113:     /* Get a "reasonably small" value that uniquely identifies this name
jjg@113:      * within its name table.
duke@1:      */
jjg@113:     public abstract int getIndex();
jjg@113: 
jjg@113:     /** Get the length (in bytes) of this name.
jjg@113:      */
jjg@113:     public abstract int getByteLength();
jjg@113: 
jjg@113:     /** Returns i'th byte of this name.
jjg@113:      */
jjg@113:     public abstract byte getByteAt(int i);
jjg@113: 
jjg@113:     /** Copy all bytes of this name to buffer cs, starting at start.
jjg@113:      */
jjg@113:     public void getBytes(byte cs[], int start) {
jjg@113:         System.arraycopy(getByteArray(), getByteOffset(), cs, start, getByteLength());
duke@1:     }
duke@1: 
jjg@113:     /** Get the underlying byte array for this name. The contents of the
jjg@113:      * array must not be modified.
duke@1:      */
jjg@113:     public abstract byte[] getByteArray();
duke@1: 
jjg@113:     /** Get the start offset of this name within its byte array.
duke@1:      */
jjg@113:     public abstract int getByteOffset();
duke@1: 
jjg@113:     /** An abstraction for the hash table used to create unique Name instances.
jjg@113:      */
jjg@113:     public static abstract class Table {
jjg@113:         /** Standard name table.
jjg@113:          */
jjg@113:         public final Names names;
duke@1: 
jjg@113:         Table(Names names) {
jjg@113:             this.names = names;
duke@1:         }
duke@1: 
jjg@113:         /** Get the name from the characters in cs[start..start+len-1].
jjg@113:          */
jjg@113:         public abstract Name fromChars(char[] cs, int start, int len);
jjg@113: 
jjg@113:         /** Get the name for the characters in string s.
jjg@113:          */
jjg@113:         public Name fromString(String s) {
jjg@113:             char[] cs = s.toCharArray();
jjg@113:             return fromChars(cs, 0, cs.length);
duke@1:         }
duke@1: 
jjg@113:         /** Get the name for the bytes in array cs.
jjg@113:          *  Assume that bytes are in utf8 format.
jjg@113:          */
jjg@113:         public Name fromUtf(byte[] cs) {
jjg@113:             return fromUtf(cs, 0, cs.length);
duke@1:         }
duke@1: 
jjg@113:         /** get the name for the bytes in cs[start..start+len-1].
jjg@113:          *  Assume that bytes are in utf8 format.
jjg@113:          */
jjg@113:         public abstract Name fromUtf(byte[] cs, int start, int len);
duke@1: 
jjg@113:         /** Release any resources used by this table.
jjg@113:          */
jjg@113:         public abstract void dispose();
jjg@113: 
jjg@113:         /** The hashcode of a name.
jjg@113:          */
jjg@113:         protected static int hashValue(byte bytes[], int offset, int length) {
jjg@113:             int h = 0;
jjg@113:             int off = offset;
jjg@113: 
jjg@113:             for (int i = 0; i < length; i++) {
jjg@113:                 h = (h << 5) - h + bytes[off++];
duke@1:             }
jjg@113:             return h;
duke@1:         }
duke@1: 
jjg@113:         /** Compare two subarrays
duke@1:          */
jjg@113:         protected static boolean equals(byte[] bytes1, int offset1,
jjg@113:                 byte[] bytes2, int offset2, int length) {
jjg@113:             int i = 0;
jjg@113:             while (i < length && bytes1[offset1 + i] == bytes2[offset2 + i]) {
jjg@113:                 i++;
jjg@113:             }
jjg@113:             return i == length;
duke@1:         }
duke@1:     }
duke@1: }