data/xulugridfile/BufferedHelper.java

package appl.parallel.data.xulugridfile;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.EOFException;
import java.io.IOException;
import java.io.RandomAccessFile;

/**
 * The methods of this class can be used to efficiently read or write values
 * into a Bytestream (it is e.g. used by the {@link XuluGridFile}).
 *
 * @author Dominik Appl
 *
 */
public class BufferedHelper {

        /**
         * Reads a long value out of the given bytestream Used for buffered reading.
         * Used the code of {@link RandomAccessFile#readInt()}
         *
         * @exception IOException
         *                if an I/O error occurs.
         */
        public static final int readIntFromStream(ByteArrayInputStream input)
                        throws IOException {
                int ch1 = input.read();
                int ch2 = input.read();
                int ch3 = input.read();
                int ch4 = input.read();
                if ((ch1 | ch2 | ch3 | ch4) < 0)
                        throw new EOFException();
                return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + (ch4 << 0));
        }

        /**
         * Writes a int value in the the given bytestream Used for buffered writing.
         * Used the code of {@link RandomAccessFile#writeInt(int)}
         *
         * @exception IOException
         *                if an I/O error occurs.
         *
         */
        public static final void writeInt(int v, ByteArrayOutputStream output)
                        throws IOException {
                output.write((v >>> 24) & 0xFF);
                output.write((v >>> 16) & 0xFF);
                output.write((v >>> 8) & 0xFF);
                output.write((v >>> 0) & 0xFF);
                // written += 4;
        }

        /**
         * Writes a <code>long</code> to the stream as eight bytes, high byte
         * first. The write starts at the current position of the file pointer. Used
         * for buffered writing. Used the code of
         * {@link RandomAccessFile#writeLong(long)}
         *
         * @param output the stream to be written to
         * @param v
         *            a <code>long</code> to be written.
         * @exception IOException
         *                if an I/O error occurs.
         */
        public static final void writeLong(long v, ByteArrayOutputStream output)
                        throws IOException {
                output.write((int) (v >>> 56) & 0xFF);
                output.write((int) (v >>> 48) & 0xFF);
                output.write((int) (v >>> 40) & 0xFF);
                output.write((int) (v >>> 32) & 0xFF);
                output.write((int) (v >>> 24) & 0xFF);
                output.write((int) (v >>> 16) & 0xFF);
                output.write((int) (v >>> 8) & 0xFF);
                output.write((int) (v >>> 0) & 0xFF);
                // written += 8;
        }

        /**
         * Reads a long value out of the given {@link ByteArrayInputStream}. Used for buffered
         * reading. Used the code of {@link RandomAccessFile#readLong()} *
         *
         * @exception IOException
         *                if an I/O error occurs.
         */
        public static final long readLongFromStream(ByteArrayInputStream input)
                        throws IOException {
                return ((long) (readIntFromStream(input) << 32) + (readIntFromStream(input) & 0xFFFFFFFFL));
        }

}
1	mojays	2	package appl.parallel.data.xulugridfile;
2
3			import java.io.ByteArrayInputStream;
4			import java.io.ByteArrayOutputStream;
5			import java.io.EOFException;
6			import java.io.IOException;
7			import java.io.RandomAccessFile;
8
9			/**
10			* The methods of this class can be used to efficiently read or write values
11			* into a Bytestream (it is e.g. used by the {@link XuluGridFile}).
12			*
13			* @author Dominik Appl
14			*
15			*/
16			public class BufferedHelper {
17
18			/**
19			* Reads a long value out of the given bytestream Used for buffered reading.
20			* Used the code of {@link RandomAccessFile#readInt()}
21			*
22			* @exception IOException
23			* if an I/O error occurs.
24			*/
25			public static final int readIntFromStream(ByteArrayInputStream input)
26			throws IOException {
27			int ch1 = input.read();
28			int ch2 = input.read();
29			int ch3 = input.read();
30			int ch4 = input.read();
31			if ((ch1 \| ch2 \| ch3 \| ch4) < 0)
32			throw new EOFException();
33			return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + (ch4 << 0));
34			}
35
36			/**
37			* Writes a int value in the the given bytestream Used for buffered writing.
38			* Used the code of {@link RandomAccessFile#writeInt(int)}
39			*
40			* @exception IOException
41			* if an I/O error occurs.
42			*
43			*/
44			public static final void writeInt(int v, ByteArrayOutputStream output)
45			throws IOException {
46			output.write((v >>> 24) & 0xFF);
47			output.write((v >>> 16) & 0xFF);
48			output.write((v >>> 8) & 0xFF);
49			output.write((v >>> 0) & 0xFF);
50			// written += 4;
51			}
52
53			/**
54			* Writes a <code>long</code> to the stream as eight bytes, high byte
55			* first. The write starts at the current position of the file pointer. Used
56			* for buffered writing. Used the code of
57			* {@link RandomAccessFile#writeLong(long)}
58			*
59			* @param output the stream to be written to
60			* @param v
61			* a <code>long</code> to be written.
62			* @exception IOException
63			* if an I/O error occurs.
64			*/
65			public static final void writeLong(long v, ByteArrayOutputStream output)
66			throws IOException {
67			output.write((int) (v >>> 56) & 0xFF);
68			output.write((int) (v >>> 48) & 0xFF);
69			output.write((int) (v >>> 40) & 0xFF);
70			output.write((int) (v >>> 32) & 0xFF);
71			output.write((int) (v >>> 24) & 0xFF);
72			output.write((int) (v >>> 16) & 0xFF);
73			output.write((int) (v >>> 8) & 0xFF);
74			output.write((int) (v >>> 0) & 0xFF);
75			// written += 8;
76			}
77
78			/**
79			* Reads a long value out of the given {@link ByteArrayInputStream}. Used for buffered
80			* reading. Used the code of {@link RandomAccessFile#readLong()} *
81			*
82			* @exception IOException
83			* if an I/O error occurs.
84			*/
85			public static final long readLongFromStream(ByteArrayInputStream input)
86			throws IOException {
87			return ((long) (readIntFromStream(input) << 32) + (readIntFromStream(input) & 0xFFFFFFFFL));
88			}
89
90			}