/*
* Copyright (c) 2002-2012, the original author or authors.
*
* This software is distributable under the BSD license. See the terms of the
* BSD license in the documentation provided with this software.
*
* http://www.opensource.org/licenses/bsd-license.php
*/
package jdk.internal.jline.console.completer;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;
import static jdk.internal.jline.internal.Preconditions.checkNotNull;
/**
* Completer which contains multiple completers and aggregates them together.
*
* @author Jason Dillon
* @since 2.3
*/
public class AggregateCompleter
implements Completer
{
private final List completers = new ArrayList();
public AggregateCompleter() {
// empty
}
/**
* Construct an AggregateCompleter with the given collection of completers.
* The completers will be used in the iteration order of the collection.
*
* @param completers the collection of completers
*/
public AggregateCompleter(final Collection completers) {
checkNotNull(completers);
this.completers.addAll(completers);
}
/**
* Construct an AggregateCompleter with the given completers.
* The completers will be used in the order given.
*
* @param completers the completers
*/
public AggregateCompleter(final Completer... completers) {
this(Arrays.asList(completers));
}
/**
* Retrieve the collection of completers currently being aggregated.
*
* @return the aggregated completers
*/
public Collection getCompleters() {
return completers;
}
/**
* Perform a completion operation across all aggregated completers.
*
* @see Completer#complete(String, int, java.util.List)
* @return the highest completion return value from all completers
*/
public int complete(final String buffer, final int cursor, final List candidates) {
// buffer could be null
checkNotNull(candidates);
List completions = new ArrayList(completers.size());
// Run each completer, saving its completion results
int max = -1;
for (Completer completer : completers) {
Completion completion = new Completion(candidates);
completion.complete(completer, buffer, cursor);
// Compute the max cursor position
max = Math.max(max, completion.cursor);
completions.add(completion);
}
// Append candidates from completions which have the same cursor position as max
for (Completion completion : completions) {
if (completion.cursor == max) {
candidates.addAll(completion.candidates);
}
}
return max;
}
/**
* @return a string representing the aggregated completers
*/
@Override
public String toString() {
return getClass().getSimpleName() + "{" +
"completers=" + completers +
'}';
}
private class Completion
{
public final List candidates;
public int cursor;
public Completion(final List candidates) {
checkNotNull(candidates);
this.candidates = new LinkedList(candidates);
}
public void complete(final Completer completer, final String buffer, final int cursor) {
checkNotNull(completer);
this.cursor = completer.complete(buffer, cursor, candidates);
}
}
}