// *************************************************************************************************************************** | |
// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file * | |
// * distributed with this work for additional information regarding copyright ownership. The ASF licenses this file * | |
// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance * | |
// * with the License. You may obtain a copy of the License at * | |
// * * | |
// * http://www.apache.org/licenses/LICENSE-2.0 * | |
// * * | |
// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an * | |
// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the * | |
// * specific language governing permissions and limitations under the License. * | |
// *************************************************************************************************************************** | |
package org.apache.juneau.internal; | |
import java.io.*; | |
/** | |
* Similar to {@link StringReader} except reads from a generic {@link CharSequenceReader}. | |
*/ | |
public final class CharSequenceReader extends BufferedReader { | |
private final CharSequence cs; | |
private String s; | |
private StringBuffer sb; | |
private StringBuilder sb2; | |
private int length; | |
private int next = 0; | |
/** | |
* Constructor. | |
* | |
* @param cs The char sequence to read from. Can be <jk>null</jk>. | |
*/ | |
public CharSequenceReader(CharSequence cs) { | |
super(new StringReader(""), 1); // Does not actually use a reader. | |
if (cs == null) | |
cs = ""; | |
this.cs = cs; | |
if (cs instanceof String) | |
s = (String)cs; | |
else if (cs instanceof StringBuffer) | |
sb = (StringBuffer)cs; | |
else if (cs instanceof StringBuilder) | |
sb2 = (StringBuilder)cs; | |
this.length = cs.length(); | |
} | |
@Override /* Reader */ | |
public int read() { | |
if (next >= length) | |
return -1; | |
return cs.charAt(next++); | |
} | |
@Override /* Reader */ | |
public boolean markSupported() { | |
return false; | |
} | |
@Override /* Reader */ | |
public int read(final char[] cbuf, final int off, final int len) { | |
if (next >= length) | |
return -1; | |
int n = Math.min(length - next, len); | |
if (s != null) | |
s.getChars(next, next + n, cbuf, off); | |
else if (sb != null) | |
sb.getChars(next, next + n, cbuf, off); | |
else if (sb2 != null) | |
sb2.getChars(next, next + n, cbuf, off); | |
else { | |
for (int i = 0; i < n; i++) | |
cbuf[off+i] = cs.charAt(next+i); | |
} | |
next += n; | |
return n; | |
} | |
@Override /* Reader */ | |
public long skip(long ns) { | |
if (next >= length) | |
return 0; | |
long n = Math.min(length - next, ns); | |
n = Math.max(-next, n); | |
next += n; | |
return n; | |
} | |
@Override /* Reader */ | |
public void close() { | |
// no-op | |
} | |
@Override /* Object */ | |
public String toString() { | |
return cs.toString(); | |
} | |
} |