org.simpleframework.xml.transform.ArrayTransform Maven / Gradle / Ivy
/*
* PrimitiveArrayTransform.java May 2007
*
* Copyright (C) 2007, Niall Gallagher
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General
* Public License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307 USA
*/
package org.simpleframework.xml.transform;
import org.simpleframework.xml.transform.StringArrayTransform;
import java.lang.reflect.Array;
/**
* The PrimitiveArrayTransform
is used to transform
* arrays to and from string representations, which will be inserted
* in the generated XML document as the value place holder. The
* value must be readable and writable in the same format. Fields
* and methods annotated with the XML attribute annotation will use
* this to persist and retrieve the value to and from the XML source.
*
*
* @Attribute
* private int[] text;
*
*
* As well as the XML attribute values using transforms, fields and
* methods annotated with the XML element annotation will use this.
* Aside from the obvious difference, the element annotation has an
* advantage over the attribute annotation in that it can maintain
* any references using the CycleStrategy
object.
*
* @author Niall Gallagher
*/
class ArrayTransform implements Transform {
/**
* This transform is used to split the comma separated values.
*/
private final StringArrayTransform split;
/**
* This is the transform that performs the individual transform.
*/
private final Transform delegate;
/**
* This is the entry type for the primitive array to be created.
*/
private final Class entry;
/**
* Constructor for the PrimitiveArrayTransform
object.
* This is used to create a transform that will create primitive
* arrays and populate the values of the array with values from a
* comma separated list of individula values for the entry type.
*
* @param delegate this is used to perform individual transforms
* @param entry this is the entry component type for the array
*/
public ArrayTransform(Transform delegate, Class entry) {
this.split = new StringArrayTransform();
this.delegate = delegate;
this.entry = entry;
}
/**
* This method is used to convert the string value given to an
* appropriate representation. This is used when an object is
* being deserialized from the XML document and the value for
* the string representation is required.
*
* @param value this is the string representation of the value
*
* @return this returns an appropriate instanced to be used
*/
public Object read(String value) throws Exception {
String[] list = split.read(value);
int length = list.length;
return read(list, length);
}
/**
* This method is used to convert the string value given to an
* appropriate representation. This is used when an object is
* being deserialized from the XML document and the value for
* the string representation is required.
*
* @param list this is the string representation of the value
* @param length this is the number of string values to use
*
* @return this returns an appropriate instanced to be used
*/
private Object read(String[] list, int length) throws Exception {
Object array = Array.newInstance(entry, length);
for(int i = 0; i < length; i++) {
Object item = delegate.read(list[i]);
if(item != null) {
Array.set(array, i, item);
}
}
return array;
}
/**
* This method is used to convert the provided value into an XML
* usable format. This is used in the serialization process when
* there is a need to convert a field value in to a string so
* that that value can be written as a valid XML entity.
*
* @param value this is the value to be converted to a string
*
* @return this is the string representation of the given value
*/
public String write(Object value) throws Exception {
int length = Array.getLength(value);
return write(value, length);
}
/**
* This method is used to convert the provided value into an XML
* usable format. This is used in the serialization process when
* there is a need to convert a field value in to a string so
* that that value can be written as a valid XML entity.
*
* @param value this is the value to be converted to a string
*
* @return this is the string representation of the given value
*/
private String write(Object value, int length) throws Exception {
String[] list = new String[length];
for(int i = 0; i < length; i++) {
Object entry = Array.get(value, i);
if(entry != null) {
list[i] = delegate.write(entry);
}
}
return split.write(list);
}
}