Java File Read via ByteBuffer readFile(File file)

Description

read File

License

Open Source License

Declaration

public static String readFile(File file) throws IOException 

Method Source Code

//package com.java2s;
/*/*ww w . j av  a  2  s  .  c  o m*/
 * Dynamic Compressor - Java Library
 * Copyright (c) 2011-2012, IntelligentCode ZhangLixin.
 * All rights reserved.
 * intelligentcodemail@gmail.com
 *
 * GUN GPL 3.0 License
 *
 * http://www.gnu.org/licenses/gpl.html
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.io.*;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.channels.FileChannel;
import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;

public class Main {

    public static String readFile(File file) throws IOException {
        if (!file.exists() || file.isDirectory() || !file.canRead()) {
            return null;
        }
        FileInputStream fileInputStream = new FileInputStream(file);
        return readFile(fileInputStream);
    }

    public static String readFile(FileInputStream fileInputStream) throws IOException {
        ByteBuffer buffer = ByteBuffer.allocate(1024);
        StringBuffer contentBuffer = new StringBuffer();
        Charset charset = null;
        CharsetDecoder decoder = null;
        CharBuffer charBuffer = null;
        try {
            FileChannel channel = fileInputStream.getChannel();
            while (true) {
                buffer.clear();
                int pos = channel.read(buffer);
                if (pos == -1) {
                    break;
                }
                buffer.flip();
                charset = Charset.forName("UTF-8");
                decoder = charset.newDecoder();
                charBuffer = decoder.decode(buffer);
                contentBuffer.append(charBuffer.toString());
            }
        } finally {
            if (fileInputStream != null) {
                try {
                    fileInputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return contentBuffer.toString();
    }
}

Related

1. readDouble(FileChannel fileChannel, ByteOrder byteOrder)
2. readDouble(final byte[] bytes, final int length, final int offset)
3. readEntireFile(java.io.File file)
4. readerToString(Reader reader)
5. readFC(String fname, int length)
6. readFile(File file)
7. readFile(File file)
8. readFile(File file)
9. readFile(File file)