org.wildfly.common.string.CompositeCharSequence Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* JBoss, Home of Professional Open Source.
* Copyright 2019 Red Hat, Inc., and individual contributors
* as indicated by the @author tags.
*
* Licensed 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.wildfly.common.string;
import java.io.Serializable;
import java.nio.CharBuffer;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
/**
* A {@link CharSequence} composed of other character sequences.
* All methods delegate to one or more of the underlying character sequences, using relative indexes.
* @author Paul Ferraro
*/
public class CompositeCharSequence implements CharSequence, Serializable {
private static final long serialVersionUID = 4975968165050531721L;
private final List sequences;
private transient int hashCode = 0;
/**
* Constructs a new composite character sequence.
* @param sequences an array of character sequences.
*/
public CompositeCharSequence(CharSequence... sequences) {
this(Arrays.asList(sequences));
}
/**
* Constructs a new composite character sequence.
* @param sequences a list of character sequences.
*/
public CompositeCharSequence(List sequences) {
this.sequences = sequences;
}
@Override
public int length() {
int length = 0;
for (CharSequence sequence : this.sequences) {
length += sequence.length();
}
return length;
}
@Override
public char charAt(int index) {
int relativeIndex = index;
for (CharSequence sequence : this.sequences) {
if (relativeIndex < sequence.length()) {
return sequence.charAt(relativeIndex);
}
relativeIndex -= sequence.length();
}
throw new IndexOutOfBoundsException();
}
@Override
public CharSequence subSequence(int start, int end) {
if ((start < 0) || (start > end) || (end > this.length())) {
throw new IndexOutOfBoundsException();
}
if (start == end) return "";
List result = null;
int relativeStart = start;
int relativeEnd = end;
for (CharSequence sequence : this.sequences) {
if ((relativeStart < sequence.length()) && (relativeEnd > 0)) {
CharSequence subSequence = sequence.subSequence(Math.max(relativeStart, 0), Math.min(relativeEnd, sequence.length()));
if (result == null) {
// If subsequence falls within a single sequence
if ((relativeStart >= 0) && (relativeEnd <= sequence.length())) {
return subSequence;
}
result = new LinkedList<>();
}
result.add(subSequence);
}
relativeStart -= sequence.length();
relativeEnd -= sequence.length();
}
return new CompositeCharSequence(result);
}
@Override
public int hashCode() {
int result = this.hashCode;
if (result == 0) {
for (int i = 0; i < this.length(); ++i) {
result = 31 * result + this.charAt(i);
}
this.hashCode = result;
}
return result;
}
@Override
public boolean equals(Object object) {
if (!(object instanceof CharSequence)) return false;
CharSequence sequence = (CharSequence) object;
int length = sequence.length();
if (this.length() != length) return false;
for (int i = 0; i < length; ++i) {
if (this.charAt(i) != sequence.charAt(i)) return false;
}
return true;
}
@Override
public String toString() {
CharBuffer buffer = CharBuffer.allocate(this.length());
for (CharSequence sequence : this.sequences) {
buffer.put(CharBuffer.wrap(sequence));
}
return String.valueOf(buffer.array());
}
}