/**************************************************************************
* Copyright (c) 2001 by Punch Telematix. All rights reserved. *
* *
* Redistribution and use in source and binary forms, with or without *
* modification, are permitted provided that the following conditions *
* are met: *
* 1. Redistributions of source code must retain the above copyright *
* notice, this list of conditions and the following disclaimer. *
* 2. Redistributions in binary form must reproduce the above copyright *
* notice, this list of conditions and the following disclaimer in the *
* documentation and/or other materials provided with the distribution. *
* 3. Neither the name of Punch Telematix nor the names of *
* other contributors may be used to endorse or promote products *
* derived from this software without specific prior written permission.*
* *
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED *
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF *
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. *
* IN NO EVENT SHALL PUNCH TELEMATIX OR OTHER CONTRIBUTORS BE LIABLE *
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR *
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF *
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR *
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, *
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE *
* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN *
* IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *
**************************************************************************/
package java.io;
public abstract class Reader {
protected Object lock;
protected Reader(){
this.lock = this;
}
protected Reader(Object lock){
if (lock == null) {
throw new NullPointerException();
}
this.lock = lock;
}
public abstract void close() throws IOException;
/**
** real implementations should be synchronized ...
*/
public abstract int read(char chars[], int off, int len) throws IOException;
public void mark(int readLimit) throws IOException {
throw new IOException("mark is not supported by "+this.getClass().getName());
}
public boolean markSupported(){
return false;
}
public int read() throws IOException {
char[] chars = new char[1];
int rd = read(chars, 0, 1);
if(rd < 1){
return -1;
}else{
return chars[0];
}
}
public int read(char[] chars) throws IOException {
return read(chars, 0, chars.length);
}
public boolean ready() throws IOException{
return false;
}
public void reset() throws IOException {
throw new IOException("reset is not supported by "+this.getClass().getName());
}
public long skip(long skip) throws IOException {
if (skip < 0){
throw new IllegalArgumentException("cannot skip "+skip+" (value must be 0 or greater)");
}
synchronized(lock){
char[] chars = new char[128];
long remain=skip;
do{
int rd = read(chars,0 , (128 > remain ? (int) remain : 128));
if (rd == -1){
break;
}
remain -= rd;
}while (remain > 0);
return skip - remain;
}
}
}