From ad3da7e33441801d7d247dc90f3f8ac43167aed6 Mon Sep 17 00:00:00 2001
From: Jeremy Grelle <jgrelle@vmware.com>
Date: Fri, 25 Jan 2008 23:42:09 +0000
Subject: [PATCH] SWF-370 - Add support for automatically adapting a returned
 list for display in a DataTable to a JSF DataModel.

---
 .../model/SerializableListDataModel.java      | 12 ++++-
 .../model/converter/DataModelConverter.java   | 29 ++++++++++++
 .../converter/DataModelConverterTests.java    | 47 +++++++++++++++++++
 3 files changed, 87 insertions(+), 1 deletion(-)
 create mode 100644 spring-faces/src/main/java/org/springframework/faces/model/converter/DataModelConverter.java
 create mode 100644 spring-faces/src/test/java/org/springframework/faces/model/converter/DataModelConverterTests.java

diff --git a/spring-faces/src/main/java/org/springframework/faces/model/SerializableListDataModel.java b/spring-faces/src/main/java/org/springframework/faces/model/SerializableListDataModel.java
index 1a05d03b..7be47aba 100644
--- a/spring-faces/src/main/java/org/springframework/faces/model/SerializableListDataModel.java
+++ b/spring-faces/src/main/java/org/springframework/faces/model/SerializableListDataModel.java
@@ -1,6 +1,7 @@
 package org.springframework.faces.model;
 
 import java.io.Serializable;
+import java.util.ArrayList;
 import java.util.List;
 
 import javax.faces.model.DataModel;
@@ -18,11 +19,18 @@ public class SerializableListDataModel extends DataModel implements Serializable
 
 	private List data;
 
+	public SerializableListDataModel() {
+		this(new ArrayList());
+	}
+
 	/**
 	 * Adapt the list to a data model;
 	 * @param list the list
 	 */
 	public SerializableListDataModel(List list) {
+		if (list == null) {
+			list = new ArrayList();
+		}
 		setWrappedData(list);
 	}
 
@@ -65,7 +73,9 @@ public class SerializableListDataModel extends DataModel implements Serializable
 	}
 
 	public void setWrappedData(Object data) {
-		Assert.notNull(data, "A non-null List is required for " + getClass());
+		if (data == null) {
+			data = new ArrayList();
+		}
 		Assert.isInstanceOf(List.class, data, "The data object for " + getClass() + " must be a List");
 		this.data = (List) data;
 		int newRowIndex = 0;
diff --git a/spring-faces/src/main/java/org/springframework/faces/model/converter/DataModelConverter.java b/spring-faces/src/main/java/org/springframework/faces/model/converter/DataModelConverter.java
new file mode 100644
index 00000000..7da09da9
--- /dev/null
+++ b/spring-faces/src/main/java/org/springframework/faces/model/converter/DataModelConverter.java
@@ -0,0 +1,29 @@
+package org.springframework.faces.model.converter;
+
+import java.lang.reflect.Constructor;
+import java.util.List;
+
+import javax.faces.model.DataModel;
+
+import org.springframework.binding.convert.ConversionContext;
+import org.springframework.binding.convert.support.AbstractConverter;
+import org.springframework.util.ClassUtils;
+
+public class DataModelConverter extends AbstractConverter {
+
+	protected Object doConvert(Object source, Class targetClass, ConversionContext context) throws Exception {
+		Constructor emptyConstructor = ClassUtils.getConstructorIfAvailable(targetClass, new Class[] {});
+		DataModel model = (DataModel) emptyConstructor.newInstance(new Object[] {});
+		model.setWrappedData(source);
+		return model;
+	}
+
+	public Class[] getSourceClasses() {
+		return new Class[] { Object[].class, List.class, Object.class };
+	}
+
+	public Class[] getTargetClasses() {
+		return new Class[] { DataModel.class };
+	}
+
+}
diff --git a/spring-faces/src/test/java/org/springframework/faces/model/converter/DataModelConverterTests.java b/spring-faces/src/test/java/org/springframework/faces/model/converter/DataModelConverterTests.java
new file mode 100644
index 00000000..5d9cb20b
--- /dev/null
+++ b/spring-faces/src/test/java/org/springframework/faces/model/converter/DataModelConverterTests.java
@@ -0,0 +1,47 @@
+package org.springframework.faces.model.converter;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.faces.model.DataModel;
+import javax.faces.model.ListDataModel;
+
+import org.springframework.binding.convert.Converter;
+import org.springframework.faces.model.SerializableListDataModel;
+
+import junit.framework.TestCase;
+
+public class DataModelConverterTests extends TestCase {
+
+	Converter converter = new DataModelConverter();
+
+	public void testConvertListToListDataModel() {
+		List sourceList = new ArrayList();
+
+		DataModel resultModel = (DataModel) converter.convert(sourceList, ListDataModel.class, null);
+
+		assertNotNull(resultModel);
+		assertSame(sourceList, resultModel.getWrappedData());
+	}
+
+	public void testConvertListToSerializableListDataModel() {
+		List sourceList = new ArrayList();
+
+		DataModel resultModel = (DataModel) converter.convert(sourceList, SerializableListDataModel.class, null);
+
+		assertNotNull(resultModel);
+		assertSame(sourceList, resultModel.getWrappedData());
+		assertTrue(resultModel instanceof Serializable);
+	}
+
+	public void testConvertListToSerializableListDataModelNullSource() {
+		List sourceList = null;
+
+		DataModel resultModel = (DataModel) converter.convert(sourceList, SerializableListDataModel.class, null);
+
+		assertNotNull(resultModel);
+		assertTrue(resultModel instanceof Serializable);
+		assertEquals(0, resultModel.getRowCount());
+	}
+}