IORoutines.java Source code

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Here is the source code for IORoutines.java

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/*
GNU LESSER GENERAL PUBLIC LICENSE
Copyright (C) 2006 The Lobo Project
    
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
    
This library 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
Lesser General Public License for more details.
    
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
    
Contact info: lobochief@users.sourceforge.net
*/
/*
 * Created on Mar 19, 2005
 */

import java.io.*;

/**
 * @author J. H. S.
 */
public class IORoutines {
    public static final byte[] LINE_BREAK_BYTES = { (byte) 13, (byte) 10 };

    public static String loadAsText(InputStream in, String encoding) throws IOException {
        return loadAsText(in, encoding, 4096);
    }

    public static String loadAsText(InputStream in, String encoding, int bufferSize) throws IOException {
        InputStreamReader reader = new InputStreamReader(in, encoding);
        char[] buffer = new char[bufferSize];
        int offset = 0;
        for (;;) {
            int remain = buffer.length - offset;
            if (remain <= 0) {
                char[] newBuffer = new char[buffer.length * 2];
                System.arraycopy(buffer, 0, newBuffer, 0, offset);
                buffer = newBuffer;
                remain = buffer.length - offset;
            }
            int numRead = reader.read(buffer, offset, remain);
            if (numRead == -1) {
                break;
            }
            offset += numRead;
        }
        return new String(buffer, 0, offset);
    }

    public static byte[] load(File file) throws IOException {
        long fileLength = file.length();
        if (fileLength > Integer.MAX_VALUE) {
            throw new IOException("File '" + file.getName() + "' too big");
        }
        InputStream in = new FileInputStream(file);
        try {
            return loadExact(in, (int) fileLength);
        } finally {
            in.close();
        }
    }

    public static byte[] load(InputStream in) throws IOException {
        return load(in, 4096);
    }

    public static byte[] load(InputStream in, int initialBufferSize) throws IOException {
        if (initialBufferSize == 0) {
            initialBufferSize = 1;
        }
        byte[] buffer = new byte[initialBufferSize];
        int offset = 0;
        for (;;) {
            int remain = buffer.length - offset;
            if (remain <= 0) {
                int newSize = buffer.length * 2;
                byte[] newBuffer = new byte[newSize];
                System.arraycopy(buffer, 0, newBuffer, 0, offset);
                buffer = newBuffer;
                remain = buffer.length - offset;
            }
            int numRead = in.read(buffer, offset, remain);
            if (numRead == -1) {
                break;
            }
            offset += numRead;
        }
        if (offset < buffer.length) {
            byte[] newBuffer = new byte[offset];
            System.arraycopy(buffer, 0, newBuffer, 0, offset);
            buffer = newBuffer;
        }
        return buffer;
    }

    public static byte[] loadExact(InputStream in, int length) throws IOException {
        byte[] buffer = new byte[length];
        int offset = 0;
        for (;;) {
            int remain = length - offset;
            if (remain <= 0) {
                break;
            }
            int numRead = in.read(buffer, offset, remain);
            if (numRead == -1) {
                throw new IOException("Reached EOF, read " + offset + " expecting " + length);
            }
            offset += numRead;
        }
        return buffer;
    }

    public static boolean equalContent(File file, byte[] content) throws IOException {
        long length = file.length();
        if (length > Integer.MAX_VALUE) {
            throw new IOException("File '" + file + "' too big");
        }
        InputStream in = new FileInputStream(file);
        try {
            byte[] fileContent = loadExact(in, (int) length);
            return java.util.Arrays.equals(content, fileContent);
        } finally {
            in.close();
        }
    }

    public static void save(File file, byte[] content) throws IOException {
        FileOutputStream out = new FileOutputStream(file);
        try {
            out.write(content);
        } finally {
            out.close();
        }
    }

    /**
     * Reads line without buffering.
     */
    public static String readLine(InputStream in) throws IOException {
        int b;
        StringBuffer sb = null;
        OUTER: while ((b = in.read()) != -1) {
            if (sb == null) {
                sb = new StringBuffer();
            }
            switch (b) {
            case (byte) '\n':
                break OUTER;
            case (byte) '\r':
                break;
            default:
                sb.append((char) b);
                break;
            }
        }
        return sb == null ? null : sb.toString();
    }

    public static void touch(File file) {
        file.setLastModified(System.currentTimeMillis());
    }

    public static void saveStrings(File file, java.util.Collection list) throws IOException {
        BufferedOutputStream bout = new BufferedOutputStream(new FileOutputStream(file));
        try {
            PrintWriter writer = new PrintWriter(bout);
            java.util.Iterator i = list.iterator();
            while (i.hasNext()) {
                String text = (String) i.next();
                writer.println(text);
            }
            writer.flush();
        } finally {
            bout.close();
        }
    }

    public static java.util.List loadStrings(File file) throws IOException {
        java.util.List list = new java.util.LinkedList();
        InputStream in = new FileInputStream(file);
        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(in));
            String line;
            while ((line = reader.readLine()) != null) {
                list.add(line);
            }
            return list;
        } finally {
            in.close();
        }
    }

}