Object-Type Attribute Value Evaluation

.gitattributes

@@ -0,0 +1,30 @@
+# Handle line endings automatically for files detected as text
+# and leave all files detected as binary untouched.
+* text=auto
+
+#
+# The above will handle all files NOT found below
+#
+# These files are text and should be normalized (Convert crlf => lf)
+*.css           text
+*.df            text
+*.java          text
+*.js            text
+*.json          text
+*.jsp           text
+*.properties    text
+*.sql           text
+*.svg           text
+*.tld           text
+*.txt           text
+*.xml           text
+
+# These files are binary and should be left untouched
+# (binary is a macro for -text -diff)
+*.dll           binary
+*.gif           binary
+*.ico           binary
+*.jar           binary
+*.png           binary
+*.so            binary
+

.gitignore

@@ -0,0 +1,25 @@
+/target/
+/tiles-api/target/
+/tiles-core/target/
+/tiles-template/target/
+/tiles-servlet/target/
+/tiles-jsp/target/
+/tiles-freemarker/target/
+/tiles-velocity/target/
+/tiles-el/target/
+/tiles-ognl/target/
+/tiles-mvel/target/
+/tiles-compat/target/
+/tiles-extras/target/
+/tiles-test-pom/tiles-test-db/target/
+/tiles-test-pom/tiles-test-alt/target/
+/tiles-test-pom/target/
+/tiles-test-pom/tiles-test-common/target/
+/tiles-test-pom/tiles-test/target/
+/assembly/target/
+*~
+*.bak
+*.swp
+*.log
+.DS_Store
+pom.xml.versionsBackup

tiles-compat/src/main/java/org/apache/tiles/beans/SimpleMenuItem.java

@@ -21,14 +21,21 @@
 package org.apache.tiles.beans;
 
 import java.io.Serializable;
+import org.apache.tiles.awareness.ExpressionAware;
+import org.apache.tiles.evaluator.AttributeEvaluator;
+import org.apache.tiles.request.Request;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * A MenuItem implementation.
  * Used to read menu items in definitions.
  *
  * @version $Rev$ $Date$
  */
-public class SimpleMenuItem implements MenuItem, Serializable {
+public class SimpleMenuItem implements MenuItem, Serializable, ExpressionAware {
+
+    private static final Logger log = LoggerFactory.getLogger(SimpleMenuItem.class);
 
     /**
      * The value of the item, i.e. what is really visible to the user.
@@ -57,6 +64,14 @@ public SimpleMenuItem() {
         super();
     }
 
+    public SimpleMenuItem(String value, String link, String icon, String tooltip) {
+        super();
+        this.value = value;
+        this.link = link;
+        this.icon = icon;
+        this.tooltip = tooltip;
+    }
+
     /**
      * Sets the value of the item, i.e. what is really visible to the user.
      *
@@ -132,26 +147,67 @@ public String getTooltip() {
     /** {@inheritDoc} */
     @Override
     public String toString() {
-        StringBuffer buff = new StringBuffer("SimpleMenuItem[");
+        StringBuilder buff = new StringBuilder("SimpleMenuItem[");
 
         if (getValue() != null) {
-            buff.append("value=").append(getValue()).append(", ");
+            buff.append("value=").append(getValue());
         }
 
         if (getLink() != null) {
-            buff.append("link=").append(getLink()).append(", ");
+            if (buff.length() > 0) {
+                buff.append(", ");
+            }
+            buff.append("link=").append(getLink());
         }
 
         if (getTooltip() != null) {
-            buff.append("tooltip=").append(getTooltip()).append(", ");
+            if (buff.length() > 0) {
+                buff.append(", ");
+            }
+            buff.append("tooltip=").append(getTooltip());
         }
 
         if (getIcon() != null) {
-            buff.append("icon=").append(getIcon()).append(", ");
+            if (buff.length() > 0) {
+                buff.append(", ");
+            }
+            buff.append("icon=").append(getIcon());
         }
 
         buff.append("]");
         return buff.toString();
     }
 
+    /**
+     * Evaluates all values for expressions replacing their contents with the
+     * result of the evaluation.
+     *
+     * In the event of a {@link ClassCastException} the original value is used.
+     *
+     * @param   eval
+     *          Evaluator instance used to evaluate expressions.
+     * @param   request
+     *          Request object to evaluate expressions with.
+     */
+    @Override
+    public Object evaluateExpressions(AttributeEvaluator eval, Request request) {
+        return new SimpleMenuItem(safeEval(eval, request, value),
+                                  safeEval(eval, request, link),
+                                  safeEval(eval, request, icon),
+                                  safeEval(eval, request, tooltip));
+    }
+
+    private String safeEval(AttributeEvaluator eval, Request request, String val) {
+        if (val == null || val.length() == 0) {
+            return val;
+        }
+        try {
+            Object res = eval.evaluate(val, request);
+            return res == null ? null : res.toString();
+        } catch (Exception ex) {
+            log.warn("Could not evaluate expressions for SimpleMenuItem: {}", ex.getMessage(), ex);
+        }
+        return val;
+    }
+
 }

tiles-compat/src/test/java/org/apache/tiles/beans/SimpleMenuItemTest.java

@@ -91,7 +91,7 @@ public void testToString() {
         item.setTooltip("tooltip");
         item.setValue("value");
         assertEquals(
-                "SimpleMenuItem[value=value, link=link, tooltip=tooltip, icon=icon, ]",
+                "SimpleMenuItem[value=value, link=link, tooltip=tooltip, icon=icon]",
                 item.toString());
     }
 

tiles-core/src/main/java/org/apache/tiles/awareness/ExpressionAware.java

@@ -0,0 +1,50 @@
+/*
+ * ExpressionAware.java    Jun 12 2015, 07:42
+ *
+ * Copyright 2015 The Apache Software Foundation.
+ *
+ * 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.apache.tiles.awareness;
+
+import org.apache.tiles.evaluator.AttributeEvaluator;
+import org.apache.tiles.request.Request;
+
+
+/**
+ * Provides the ability for extended attributes a mechanism for evaluating
+ * expressions.
+ *
+ * Objects will have {@link #evaluateExpressions(AttributeEvaluator, Request) evaluateExpressions}
+ * called which leaves the evaluation up to the object in question.
+ *
+ * @author  Brett Ryan
+ * @since   3.0.6
+ */
+public interface ExpressionAware {
+
+    /**
+     * Evaluate supported expressions on object.
+     *
+     * Implementors may return any type for view rendering.
+     *
+     * @param   eval
+     *          Evaluator instance used to evaluate expressions.
+     * @param   request
+     *          Request object to evaluate expressions with.
+     * @return  Model instance with attributes evaluated.
+     */
+    Object evaluateExpressions(AttributeEvaluator eval, Request request);
+
+}

tiles-core/src/main/java/org/apache/tiles/evaluator/AbstractAttributeEvaluator.java

@@ -20,9 +20,14 @@
  */
 package org.apache.tiles.evaluator;
 
+import java.util.ArrayList;
+import java.util.List;
 import org.apache.tiles.Attribute;
 import org.apache.tiles.Expression;
+import org.apache.tiles.awareness.ExpressionAware;
 import org.apache.tiles.request.Request;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Abstract class to link a correct evaluation of an attribute, by evaluating
@@ -33,7 +38,10 @@
  */
 public abstract class AbstractAttributeEvaluator implements AttributeEvaluator {
 
+    private static final Logger log = LoggerFactory.getLogger(AbstractAttributeEvaluator.class);
+
     /** {@inheritDoc} */
+    @Override
     public Object evaluate(Attribute attribute, Request request) {
         if (attribute == null) {
             throw new IllegalArgumentException("The attribute cannot be null");
@@ -44,9 +52,27 @@ public Object evaluate(Attribute attribute, Request request) {
         if (retValue == null) {
             Expression expression = attribute.getExpressionObject();
             if (expression != null) {
+                log.debug("Evaluating expression: [attribute={},expression={}]", attribute, expression);
                 retValue = evaluate(attribute.getExpressionObject()
                         .getExpression(), request);
             }
+        } else if (retValue instanceof List) {
+            log.debug("Evaluating iterable for expressions: [attribute={},retValue={}]", attribute, retValue);
+            List list = (List)retValue;
+            List newList = new ArrayList(list.size());
+            for (Object n : list) {
+                if (n instanceof Attribute) {
+                    Attribute m = (Attribute) n;
+                    if (m.getValue() instanceof ExpressionAware) {
+                        log.debug("Evaluating expression-aware value: [object={}]", n);
+                        m = new Attribute(m);
+                        m.setValue(((ExpressionAware)m.getValue()).evaluateExpressions(this, request));
+                    }
+                    n = m;
+                }
+                newList.add(n);
+            }
+            retValue = newList;
         }
 
         return retValue;

tiles-el/src/test/java/org/apache/tiles/el/ELAttributeEvaluatorTest.java

@@ -20,8 +20,10 @@
  */
 package org.apache.tiles.el;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 
 import javax.el.ArrayELResolver;
@@ -37,10 +39,15 @@
 import org.apache.el.ExpressionFactoryImpl;
 import org.apache.tiles.Attribute;
 import org.apache.tiles.Expression;
+import org.apache.tiles.awareness.ExpressionAware;
+import org.apache.tiles.evaluator.AttributeEvaluator;
 import org.apache.tiles.request.ApplicationContext;
 import org.apache.tiles.request.Request;
 import org.easymock.EasyMock;
 
+import static org.hamcrest.CoreMatchers.instanceOf;
+import static org.junit.Assert.assertThat;
+
 /**
  * Tests {@link ELAttributeEvaluator}.
  *
@@ -171,6 +178,66 @@ public void testEvaluateString() {
                 .evaluate(expression, request));
     }
 
+    public void testEvaluateExpressionAware() {
+        List<Attribute> list = new ArrayList<Attribute>();
+        list.add(new Attribute(new Explosion("${requestScope.object1}")));
+        list.add(new Attribute(new Explosion("${sessionScope.object2}")));
+        list.add(new Attribute(new Explosion("${applicationScope.object3}")));
+        list.add(new Attribute(new Explosion("${object1}")));
+        list.add(new Attribute(new Explosion("${object2}")));
+        list.add(new Attribute(new Explosion("${object3}")));
+        list.add(new Attribute(new Explosion("${paulaBean.paula}")));
+        list.add(new Attribute(new Explosion("String literal")));
+        Attribute attribute = new Attribute(list);
+
+        Object res = evaluator.evaluate(attribute, request);
+
+        assertThat("Evaluated instance is not a List.", res, instanceOf(List.class));
+
+        List<Attribute> nlist = (List<Attribute>)res;
+        int i = 0;
+        assertEquals("The value is not correct", "value", ((Explosion)nlist.get(i++).getValue()).getValue());
+        assertEquals("The value is not correct", new Integer(1), ((Explosion)nlist.get(i++).getValue()).getValue());
+        assertEquals("The value is not correct", new Float(2.0), ((Explosion)nlist.get(i++).getValue()).getValue());
+        assertEquals("The value is not correct", "value", ((Explosion)nlist.get(i++).getValue()).getValue());
+        assertEquals("The value is not correct", new Integer(1), ((Explosion)nlist.get(i++).getValue()).getValue());
+        assertEquals("The value is not correct", new Float(2.0), ((Explosion)nlist.get(i++).getValue()).getValue());
+        assertEquals("The value is not correct", "Brillant", ((Explosion)nlist.get(i++).getValue()).getValue());
+        assertEquals("The value is not correct", "String literal", ((Explosion)nlist.get(i++).getValue()).getValue());
+    }
+
+    private static final class Explosion implements ExpressionAware {
+
+        private final Object value;
+
+        public Explosion(Object value) {
+            this.value = value;
+        }
+
+        public Object getValue() {
+            return value;
+        }
+
+        @Override
+        public Object evaluateExpressions(AttributeEvaluator eval, Request request) {
+            return new Explosion(safeEval(eval, request, value));
+        }
+
+        private Object safeEval(AttributeEvaluator eval, Request request, Object val) {
+            if (val == null) {
+                return val;
+            }
+            if (val instanceof String) {
+                String n = (String) val;
+                if (n.length() == 0) {
+                    return n;
+                }
+                return eval.evaluate(n, request);
+            }
+            return val;
+        }
+    }
+
     /**
      * This is The Brillant Paula Bean (sic) just like it was posted to:
      * http://thedailywtf.com/Articles/The_Brillant_Paula_Bean.aspx