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'databene commons' is an open source Java library by Volker Bergmann.
It provides extensions to the Java core library by utility classes, abstract concepts
and concrete implementations.
/*
* Copyright (C) 2004-2014 Volker Bergmann ([email protected]).
* All rights reserved.
*
* 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.databene.commons.converter;
import org.databene.commons.ArrayUtil;
import org.databene.commons.BeanUtil;
import java.lang.reflect.Array;
import java.lang.reflect.Method;
import java.util.Collection;
/**
* Converts arrays and collections to arrays and other object to an array of size 1.
* Note: The target type is not declared Object[], since we also want to create byte[].
*
* Created: 26.08.2007 16:01:38
* @author Volker Bergmann
*/
@SuppressWarnings({ "unchecked", "rawtypes" })
public class ToArrayConverter extends ThreadSafeConverter {
private Class componentType;
private boolean nullToEmpty;
// constructors ----------------------------------------------------------------------------------------------------
public ToArrayConverter() {
this(Object.class);
}
public ToArrayConverter(Class componentType) {
this(componentType, true);
}
public ToArrayConverter(Class componentType, boolean nullToEmpty) {
super(Object.class, ArrayUtil.arrayType(componentType));
this.componentType = componentType;
this.nullToEmpty = nullToEmpty;
}
// properties ------------------------------------------------------------------------------------------------------
public void setNullToEmpty(boolean nullToEmpty) {
this.nullToEmpty = nullToEmpty;
}
// Converter interface implementation ------------------------------------------------------------------------------
@Override
public Object convert(Object sourceValue) {
return convert(sourceValue, componentType, nullToEmpty);
}
// static utility methods ------------------------------------------------------------------------------------------
public static Object convert(Object sourceValue, Class componentType) {
return convert(sourceValue, componentType, true);
}
@SuppressWarnings("cast")
public static Object convert(Object sourceValue, Class componentType, boolean nullToEmpty) {
if (sourceValue == null)
return (nullToEmpty ? ArrayUtil.buildArrayOfType(componentType) : null);
if (sourceValue instanceof Collection) {
Collection col = (Collection) sourceValue;
Object[] array = (Object[]) Array.newInstance(componentType, col.size());
int count = 0;
for (Object item : col)
array[count++] = item;
return array;
} else if (componentType == byte.class) {
Method method = BeanUtil.getMethod(sourceValue.getClass(), "getBytes");
if (method != null)
return (byte[]) BeanUtil.invoke(sourceValue, method, null);
else
throw new UnsupportedOperationException("Conversion not supported: " + sourceValue.getClass() + " -> " + componentType + "[]");
} else if (sourceValue.getClass().isArray()) {
return ArrayUtil.buildArrayOfType(componentType, (Object[]) sourceValue);
} else {
return ArrayUtil.buildArrayOfType(componentType, sourceValue);
}
}
@Override
public String toString() {
return getClass().getSimpleName() + "(" + componentType + ")";
}
}