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'DatabeneScript' is an open source software library for resolving Java-like script expressions, written by Volker Bergmann.
/*
* (c) Copyright 2010-2011 by Volker Bergmann. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, is permitted under the terms of the
* GNU General Public License (GPL).
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* WITHOUT A WARRANTY OF ANY KIND. ALL EXPRESS OR IMPLIED CONDITIONS,
* REPRESENTATIONS AND WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE
* HEREBY EXCLUDED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 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 org.databene.script.expression;
import org.databene.commons.ArrayUtil;
import org.databene.commons.Context;
import org.databene.script.Expression;
/**
* {@link Expression} implementation which assembles other expression that evaluate to arrays
* and joins their results to a single array.
* Created: 11.09.2010 07:57:38
* @since 0.5.4
* @author Volker Bergmann
*/
public class ArrayJoinExpression extends CompositeExpression {
private Class componentType;
public ArrayJoinExpression(Class componentType, Expression... terms) {
super(terms);
this.componentType = componentType;
}
@SuppressWarnings("unchecked")
public E[] evaluate(Context context) {
E[][] arrays = (E[][]) ExpressionUtil.evaluateAll(terms, context);
int totalLength = totalLength(arrays);
E[] result = ArrayUtil.newInstance(componentType(arrays), totalLength);
int resultIndex = 0;
for (E[] array : arrays)
for (int localIndex = 0; localIndex < array.length; localIndex++)
result[resultIndex] = array[localIndex];
return result;
}
@SuppressWarnings("unchecked")
private Class componentType(E[][] arrays) {
if (this.componentType == null) {
for (E[] array : arrays)
if (array != null) {
this.componentType = (Class) array.getClass().getComponentType();
break;
}
}
return (this.componentType != null ? this.componentType : (Class) Object.class);
}
private int totalLength(E[][] arrays) {
int totalLength = 0;
for (E[] array : arrays)
totalLength += array.length;
return totalLength;
}
}