You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
yacy_search_server/source/net/yacy/kelondro/io/AbstractReader.java

80 lines
2.9 KiB

// AbstractReader.java
// -------------------------------
// (C) 2009 by Michael Peter Christen; mc@yacy.net
// first published on http://www.anomic.de
// Frankfurt, Germany, 09.09.2009
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// 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 2 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, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package net.yacy.kelondro.io;
import java.io.File;
import java.io.IOException;
public abstract class AbstractReader implements Reader {
// logging support
protected String name = null;
protected File file = null;
public String name() {
return name;
}
public File file() {
return file;
}
// pseudo-native methods:
abstract public void readFully(byte[] b, int off, int len) throws IOException;
abstract public long length() throws IOException;
abstract public long available() throws IOException;
abstract public void seek(long pos) throws IOException;
abstract public void close() throws IOException;
// derived methods:
public final byte[] readFully() throws IOException {
long a = this.available();
if (a <= 0) return null;
if (a > Integer.MAX_VALUE) throw new IOException("available too large for a single array");
final byte[] buffer = new byte[(int) a];
this.readFully(buffer, 0, (int) a);
return buffer;
}
public final short readShort() throws IOException {
byte[] b = new byte[2];
this.readFully(b, 0, 2);
//if ((b[0] | b[1]) < 0) throw new IOException("kelondroAbstractRA.readInt: wrong values; ch1=" + (b[0] & 0xFF) + ", ch2=" + (b[1] & 0xFF));
return (short) (((b[0] & 0xFF) << 8) | (b[1] & 0xFF));
}
public final int readInt() throws IOException {
byte[] b = new byte[4];
this.readFully(b, 0, 4);
//if ((b[0] | b[1] | b[2] | b[3]) < 0) throw new IOException("kelondroAbstractRA.readInt: wrong values; ch1=" + (b[0] & 0xFF) + ", ch2=" + (b[1] & 0xFF) + ", ch3=" + (b[2] & 0xFF) + ", ch4=" + (b[3] & 0xFF));
return (((b[0] & 0xFF) << 24) | ((b[1] & 0xFF) << 16) | ((b[2] & 0xFF) << 8) | (b[3] & 0xFF));
}
public final long readLong() throws IOException {
return ((long) (readInt()) << 32) | (readInt() & 0xFFFFFFFFL);
}
}