robert burrell donkin wrote:
On Wed, 2005-09-14 at 23:23 +0200, Holger Haag wrote:
Hi all,
I am trying to serialize and deserialize a HashMap using betwixt
(version 0.6). Serialization (Converting the bean to XML) works fine but
deserialization does not. The map is always empty. To isolate the
problems I have created a unit test which should succeed but ... fails.
betwixt is a bean-based mapper. to map constructs such as maps, it
extends the concept of a simple property with getter and setting to a
complex property which has a map getter and a putter taking the key and
value.
ItemMap doesn't match this pattern (item contains it's own key and so
the matching property is an adder not a putter) and so the read fails.
i suppose that the right way to handle this situation would for the
mapper to write the values (only) without keys and then use the adder
for reading. it's not easy to persuade betwixt to do this. in terms of a
quick fix, the best approach might be to expose an iterator for the
values and map than to the adder.
if this isn't satisfactory, then post again and i'll see whether i can
describe a mapping that would do that.
- robert
Hello Robert,
thank you very much for the information and your time. I actually have
the same problems with maps and lists, so maybe the map example was not
the best choice.
The problem remains pretty much the same:
I am trying to serialize and deserialize a List (generic ArrayList<>)
using betwixt (version 0.6). Serialization (Converting the bean to XML)
works fine but deserialization does not. The map is always empty. To
isolate the problems I have created a unit test which should succeed but
... fails.
The files for ItemListTest are as follows:
Item.betwixt
============
<?xml version='1.0' encoding='UTF-8' ?>
<info primitiveTypes="element">
<element name='item'>
<element name="itemId" property="itemId"/>
<element name="name" property="name"/>
</element>
</info>
ItemList.betwixt
================
<?xml version='1.0' encoding='UTF-8' ?>
<info primitiveTypes="element">
<element name='itemList'>
<element name="item" property="items"/>
</element>
</info>
Item.java
=========
public class Item {
private String itemId;
public String getItemId() {
return itemId;
}
public void setItemId(String key) {
this.itemId = key;
}
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Override
public String toString() {
return getItemId() + "=" + getName();
}
}
ItemList.java
=============
import java.util.ArrayList;
public class ItemList extends ArrayList<Item>{
public void addItem(final Item item) {
add(item);
}
public ItemList getItems() {
return this;
}
}
ItemListTest.java
=================
import java.io.File;
import java.io.FileWriter;
import org.apache.commons.betwixt.io.BeanReader;
import org.apache.commons.betwixt.io.BeanWriter;
import junit.framework.TestCase;
public class ItemListTest extends TestCase {
public void test() {
try {
final File file = new File("/temp/itemList.xml");
System.out.println("file: " + file);
final Item item0 = new Item();
item0.setItemId("item0");
item0.setName("name0");
final Item item1 = new Item();
item1.setItemId("item1");
item1.setName("name1");
final ItemList itemList = new ItemList();
itemList.addItem(item0);
itemList.addItem(item1);
System.out.println("Written: " + itemList);
final FileWriter fWriter = new FileWriter(file);
final BeanWriter bWriter = new BeanWriter(fWriter);
bWriter.enablePrettyPrint();
bWriter.write("itemList", itemList);
bWriter.flush();
fWriter.flush();
bWriter.close();
fWriter.close();
BeanReader reader = new BeanReader();
reader.registerBeanClass("itemList", ItemList.class);
final Object parsed1 = reader.parse(file);
System.out.println("parsed1: " + parsed1);
System.out.println("parsed1.class: " + parsed1.getClass());
final ItemList parsed2 = (ItemList)parsed1;
System.out.println("parsed2: " + parsed2);
assertEquals(itemList.size(), parsed2.size());
} catch(final Exception ex) {
ex.printStackTrace();
fail(ex.getMessage());
}
}
}
Rgds
Holger
