src/share/classes/com/sun/tools/sjavac/comp/SmartWriter.java

Sat, 07 Nov 2020 10:30:02 +0800

author
aoqi
date
Sat, 07 Nov 2020 10:30:02 +0800
changeset 3938
93012e2a5d1d
parent 2525
2eb010b6cb22
permissions
-rw-r--r--

Added tag mips-jdk8u275-b01 for changeset eb6ee6a5f2fe

     1 /*
     2  * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.  Oracle designates this
     8  * particular file as subject to the "Classpath" exception as provided
     9  * by Oracle in the LICENSE file that accompanied this code.
    10  *
    11  * This code is distributed in the hope that it will be useful, but WITHOUT
    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    14  * version 2 for more details (a copy is included in the LICENSE file that
    15  * accompanied this code).
    16  *
    17  * You should have received a copy of the GNU General Public License version
    18  * 2 along with this work; if not, write to the Free Software Foundation,
    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    20  *
    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    22  * or visit www.oracle.com if you need additional information or have any
    23  * questions.
    24  */
    25 package com.sun.tools.sjavac.comp;
    27 import java.io.*;
    28 import javax.tools.JavaFileObject;
    30 /**
    31  * The SmartWriter will cache the written data and when the writer is closed,
    32  * then it will compare the cached data with the old_content string.
    33  * If different, then it will write all the new content to the file.
    34  * If not, the file is not touched.
    35  *
    36  *  <p><b>This is NOT part of any supported API.
    37  * If you write code that depends on this, you do so at your own
    38  * risk.  This code and its internal interfaces are subject to change
    39  * or deletion without notice.</b></p>
    40  */
    41 public class SmartWriter extends Writer {
    43     String name;
    44     JavaFileObject file;
    45     String oldContent;
    46     StringWriter newContent = new StringWriter();
    47     PrintWriter stdout;
    48     boolean closed;
    49     public SmartWriter(JavaFileObject f, String s, String n, PrintWriter pw) {
    50         name = n;
    51         file = f;
    52         oldContent = s;
    53         newContent = new StringWriter();
    54         stdout = pw;
    55         closed = false;
    56     }
    58     public void write(char[] chars, int i, int i1)
    59     {
    60         newContent.write(chars, i, i1);
    61     }
    63     public void close() throws IOException {
    64         if (closed) return;
    65         closed = true;
    66         String s = newContent.toString();
    67         if (!oldContent.equals(s)) {
    68             int p = file.getName().lastIndexOf(File.separatorChar);
    69             try (Writer writer = file.openWriter()) {
    70                 writer.write(s);
    71             }
    72             stdout.println("Writing "+file.getName().substring(p+1));
    73         }
    74     }
    76     public void flush() throws IOException {
    77     }
    78 }

mercurial