Author: oheger
Date: Sat Feb 1 20:30:35 2014
New Revision: 1563463
URL: http://svn.apache.org/r1563463
Log:
Added QueryResult class.
This class represents the results of a query() operation of an
ExpressionEngine. Results can be both nodes and attributes.
Added:
commons/proper/configuration/branches/immutableNodes/src/main/java/org/apache/commons/configuration/tree/QueryResult.java
commons/proper/configuration/branches/immutableNodes/src/test/java/org/apache/commons/configuration/tree/TestQueryResult.java
Added:
commons/proper/configuration/branches/immutableNodes/src/main/java/org/apache/commons/configuration/tree/QueryResult.java
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/immutableNodes/src/main/java/org/apache/commons/configuration/tree/QueryResult.java?rev=1563463&view=auto
==============================================================================
---
commons/proper/configuration/branches/immutableNodes/src/main/java/org/apache/commons/configuration/tree/QueryResult.java
(added)
+++
commons/proper/configuration/branches/immutableNodes/src/main/java/org/apache/commons/configuration/tree/QueryResult.java
Sat Feb 1 20:30:35 2014
@@ -0,0 +1,201 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.commons.configuration.tree;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.builder.EqualsBuilder;
+import org.apache.commons.lang3.builder.HashCodeBuilder;
+import org.apache.commons.lang3.builder.ToStringBuilder;
+
+/**
+ * <p>
+ * A data class representing a single query result produced by an
+ * {@link ExpressionEngine}.
+ * </p>
+ * <p>
+ * When passing a key to the {@code query()} method of {@code ExpressionEngine}
+ * the result can be a set of nodes or attributes - depending on the key. This
+ * class can represent both types of results. The aim is to give a user of
+ * {@code ExpressionEngine} all information needed for evaluating the results
+ * returned.
+ * </p>
+ * <p>
+ * Implementation note: Instances are immutable. They are created using the
+ * static factory methods.
+ * </p>
+ *
+ * @version $Id$
+ * @since 2.0
+ * @param <T> the type of the result nodes
+ */
+public final class QueryResult<T>
+{
+ /** The node result. */
+ private final T node;
+
+ /** The name of the result attribute. */
+ private final String attributeName;
+
+ /**
+ * Creates a new instance of {@code QueryResult}.
+ *
+ * @param nd the node
+ * @param attr the attribute name
+ */
+ private QueryResult(T nd, String attr)
+ {
+ node = nd;
+ attributeName = attr;
+ }
+
+ /**
+ * Creates a {@code QueryResult} instance representing the specified result
+ * node.
+ *
+ * @param <T> the type of the result node
+ * @param resultNode the result node
+ * @return the newly created instance
+ */
+ public static <T> QueryResult<T> createNodeResult(T resultNode)
+ {
+ return new QueryResult<T>(resultNode, null);
+ }
+
+ /**
+ * Creates a {@code QueryResult} instance representing an attribute result.
+ * An attribute result consists of the node the attribute belongs to and
the
+ * attribute name. (The value can be obtained based on this information.)
+ *
+ * @param parentNode the node which owns the attribute
+ * @param attrName the attribute name
+ * @param <T> the type of the parent node
+ * @return the newly created instance
+ */
+ public static <T> QueryResult<T> createAttributeResult(T parentNode,
+ String attrName)
+ {
+ return new QueryResult<T>(parentNode, attrName);
+ }
+
+ /**
+ * Returns the node referenced by this object. Depending on the result
type,
+ * this is either the result node or the parent node of the represented
+ * attribute.
+ *
+ * @return the referenced node
+ */
+ public T getNode()
+ {
+ return node;
+ }
+
+ /**
+ * Returns the name of the attribute. This method is defined only for
+ * results of type attribute.
+ *
+ * @return the attribute name
+ */
+ public String getAttributeName()
+ {
+ return attributeName;
+ }
+
+ /**
+ * Returns a flag whether this is a result of type attribute. If result is
+ * <b>true</b>, the attribute name and value can be queried. Otherwise,
only
+ * the result node is available.
+ *
+ * @return <b>true</b> for an attribute result, <b>false</b> otherwise
+ */
+ public boolean isAttributeResult()
+ {
+ return StringUtils.isNotEmpty(getAttributeName());
+ }
+
+ /**
+ * Returns the attribute value if this is an attribute result. If this is
+ * not an attribute result, an exception is thrown.
+ *
+ * @param handler the {@code NodeHandler}
+ * @return the attribute value
+ * @throws IllegalStateException if this is not an attribute result
+ */
+ public Object getAttributeValue(NodeHandler<T> handler)
+ {
+ if (!isAttributeResult())
+ {
+ throw new IllegalStateException("This is not an attribute result! "
+ + "Attribute value cannot be fetched.");
+ }
+ return handler.getAttributeValue(getNode(), getAttributeName());
+ }
+
+ @Override
+ public int hashCode()
+ {
+ return new HashCodeBuilder().append(getNode())
+ .append(getAttributeName()).toHashCode();
+ }
+
+ /**
+ * Compares this object with another one. Two instances of
+ * {@code QueryResult} are considered equal if they are of the same result
+ * type and have the same properties.
+ *
+ * @param obj the object to compare to
+ * @return a flag whether these objects are equal
+ */
+ @Override
+ public boolean equals(Object obj)
+ {
+ if (this == obj)
+ {
+ return true;
+ }
+ if (!(obj instanceof QueryResult))
+ {
+ return false;
+ }
+
+ QueryResult<?> c = (QueryResult<?>) obj;
+ return new EqualsBuilder().append(getNode(), c.getNode())
+ .append(getAttributeName(), c.getAttributeName()).isEquals();
+ }
+
+ /**
+ * Returns a string representation of this object. Depending on the result
+ * type either the result node or the parent node and the attribute name
are
+ * contained in this string.
+ *
+ * @return a string for this object
+ */
+ @Override
+ public String toString()
+ {
+ ToStringBuilder sb = new ToStringBuilder(this);
+ if (isAttributeResult())
+ {
+ sb.append("parentNode", getNode()).append("attribute",
+ getAttributeName());
+ }
+ else
+ {
+ sb.append("resultNode", getNode());
+ }
+ return sb.toString();
+ }
+}
Added:
commons/proper/configuration/branches/immutableNodes/src/test/java/org/apache/commons/configuration/tree/TestQueryResult.java
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/branches/immutableNodes/src/test/java/org/apache/commons/configuration/tree/TestQueryResult.java?rev=1563463&view=auto
==============================================================================
---
commons/proper/configuration/branches/immutableNodes/src/test/java/org/apache/commons/configuration/tree/TestQueryResult.java
(added)
+++
commons/proper/configuration/branches/immutableNodes/src/test/java/org/apache/commons/configuration/tree/TestQueryResult.java
Sat Feb 1 20:30:35 2014
@@ -0,0 +1,177 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.commons.configuration.tree;
+
+import static org.apache.commons.configuration.ConfigurationAssert.checkEquals;
+import static org.hamcrest.CoreMatchers.containsString;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+/**
+ * Test class for {@code QueryResult}.
+ *
+ * @version $Id$
+ */
+public class TestQueryResult
+{
+ /** Constant for an attribute name. */
+ private static final String ATTR = "testAttribute";
+
+ /** Constant for an attribute value. */
+ private static final Object VALUE = "Value of my attribute";
+
+ /** A test result node. */
+ private static ImmutableNode resultNode;
+
+ /** A test parent node for an attribute. */
+ private static ImmutableNode attributeNode;
+
+ @BeforeClass
+ public static void setUpBeforeClass()
+ {
+ resultNode =
+ new ImmutableNode.Builder().name("resultNode").value(42)
+ .create();
+ attributeNode =
+ new ImmutableNode.Builder().name("attributeNode")
+ .addAttribute(ATTR, VALUE).create();
+ }
+
+ /**
+ * Tests isAttributeResult() if the expected result is true.
+ */
+ @Test
+ public void testIsAttributeResultTrue()
+ {
+ QueryResult<ImmutableNode> result =
+ QueryResult.createAttributeResult(attributeNode, ATTR);
+ assertTrue("Not an attribute result", result.isAttributeResult());
+ }
+
+ /**
+ * Tests is attributeResult() if the expected result is false.
+ */
+ @Test
+ public void testIsAttributeResultFalse()
+ {
+ QueryResult<ImmutableNode> result =
+ QueryResult.createNodeResult(resultNode);
+ assertFalse("An attribute result", result.isAttributeResult());
+ }
+
+ /**
+ * Tests whether the attribute's value can be queried.
+ */
+ @Test
+ public void testGetAttributeValue()
+ {
+ QueryResult<ImmutableNode> result =
+ QueryResult.createAttributeResult(attributeNode, ATTR);
+ assertEquals("Wrong value", VALUE,
+ result.getAttributeValue(new InMemoryNodeModel()));
+ }
+
+ /**
+ * Tries to query an attribute value for a non-attribute result.
+ */
+ @Test(expected = IllegalStateException.class)
+ public void testGetAttributeValueNoAttributeResult()
+ {
+ QueryResult<ImmutableNode> result =
+ QueryResult.createNodeResult(resultNode);
+ result.getAttributeValue(new InMemoryNodeModel());
+ }
+
+ /**
+ * Tests equals() if the expected result is true.
+ */
+ @Test
+ public void testEqualsTrue()
+ {
+ QueryResult<ImmutableNode> r1 =
+ QueryResult.createNodeResult(resultNode);
+ checkEquals(r1, r1, true);
+ QueryResult<ImmutableNode> r2 =
+ QueryResult.createNodeResult(resultNode);
+ checkEquals(r1, r2, true);
+ r1 = QueryResult.createAttributeResult(attributeNode, ATTR);
+ r2 = QueryResult.createAttributeResult(attributeNode, ATTR);
+ checkEquals(r1, r2, true);
+ }
+
+ /**
+ * Tests equals() if the expected result is false.
+ */
+ @Test
+ public void testEqualsFalse()
+ {
+ QueryResult<ImmutableNode> nodeRes =
+ QueryResult.createNodeResult(resultNode);
+ QueryResult<ImmutableNode> attrRes =
+ QueryResult.createAttributeResult(attributeNode, ATTR);
+ checkEquals(nodeRes, attrRes, false);
+ QueryResult<ImmutableNode> res =
+ QueryResult.createNodeResult(attributeNode);
+ checkEquals(nodeRes, res, false);
+ res = QueryResult.createAttributeResult(attributeNode, "otherAttr");
+ checkEquals(attrRes, res, false);
+ res = QueryResult.createAttributeResult(resultNode, ATTR);
+ checkEquals(attrRes, res, false);
+ }
+
+ /**
+ * Tests equals() with other objects.
+ */
+ @Test
+ public void testEqualsOtherObjects()
+ {
+ QueryResult<ImmutableNode> result =
+ QueryResult.createNodeResult(resultNode);
+ checkEquals(result, null, false);
+ checkEquals(result, this, false);
+ }
+
+ /**
+ * Tests the string representation of a node result.
+ */
+ @Test
+ public void testToStringNodeResult()
+ {
+ QueryResult<ImmutableNode> result =
+ QueryResult.createNodeResult(resultNode);
+ assertThat(result.toString(),
+ containsString("resultNode=" + resultNode));
+ }
+
+ /**
+ * Tests the string representation of an attribute result.
+ */
+ @Test
+ public void testToStringAttributeResult()
+ {
+ QueryResult<ImmutableNode> result =
+ QueryResult.createAttributeResult(attributeNode, ATTR);
+ String s = result.toString();
+ assertThat(s, containsString("attribute=" + ATTR));
+ assertThat(s, containsString("parentNode=" + attributeNode));
+ }
+}
