Add PredicateDecorator to provide consistent access to predicates

based on code from Brian Lloyd-Newberry


git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/collections/trunk@131756 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/commons/collections/functors/AllPredicate.java

@@ -24,11 +24,11 @@ import org.apache.commons.collections.Predicate;
  * Predicate implementation that returns true if all the predicates return true.
  * 
  * @since Commons Collections 3.0
- * @version $Revision: 1.5 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.6 $ $Date: 2004/05/31 16:43:17 $
  *
  * @author Stephen Colebourne
  */
-public final class AllPredicate implements Predicate, Serializable {
+public final class AllPredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = -3094696765038308799L;

src/java/org/apache/commons/collections/functors/AndPredicate.java

@@ -23,11 +23,11 @@ import org.apache.commons.collections.Predicate;
  * Predicate implementation that returns true if both the predicates return true.
  * 
  * @since Commons Collections 3.0
- * @version $Revision: 1.5 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.6 $ $Date: 2004/05/31 16:43:17 $
  *
  * @author Stephen Colebourne
  */
-public final class AndPredicate implements Predicate, Serializable {
+public final class AndPredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = 4189014213763186912L;
@@ -76,23 +76,13 @@ public final class AndPredicate implements Predicate, Serializable {
     }
 
     /**
-     * Gets the first predicate.
+     * Gets the two predicates being decorated as an array.
      * 
-     * @return the predicate
+     * @return the predicates
      * @since Commons Collections 3.1
      */
-    public Predicate getPredicate1() {
+    public Predicate[] getPredicates() {
-        return iPredicate1;
+        return new Predicate[] {iPredicate1, iPredicate2};
-    }
-
-    /**
-     * Gets the second predicate.
-     * 
-     * @return the predicate
-     * @since Commons Collections 3.1
-     */
-    public Predicate getPredicate2() {
-        return iPredicate2;
     }
 
 }

src/java/org/apache/commons/collections/functors/AnyPredicate.java

@@ -24,11 +24,11 @@ import org.apache.commons.collections.Predicate;
  * Predicate implementation that returns true if any of the predicates return true.
  * 
  * @since Commons Collections 3.0
- * @version $Revision: 1.5 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.6 $ $Date: 2004/05/31 16:43:17 $
  *
  * @author Stephen Colebourne
  */
-public final class AnyPredicate implements Predicate, Serializable {
+public final class AnyPredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = 7429999530934647542L;

src/java/org/apache/commons/collections/functors/NonePredicate.java

@@ -24,11 +24,11 @@ import org.apache.commons.collections.Predicate;
  * Predicate implementation that returns true if none of the predicates return true.
  * 
  * @since Commons Collections 3.0
- * @version $Revision: 1.5 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.6 $ $Date: 2004/05/31 16:43:17 $
  *
  * @author Stephen Colebourne
  */
-public final class NonePredicate implements Predicate, Serializable {
+public final class NonePredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = 2007613066565892961L;

src/java/org/apache/commons/collections/functors/NotPredicate.java

@@ -23,11 +23,11 @@ import org.apache.commons.collections.Predicate;
  * Predicate implementation that returns the opposite of the decorated predicate.
  * 
  * @since Commons Collections 3.0
- * @version $Revision: 1.5 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.6 $ $Date: 2004/05/31 16:43:17 $
  *
  * @author Stephen Colebourne
  */
-public final class NotPredicate implements Predicate, Serializable {
+public final class NotPredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = -2654603322338049674L;
@@ -71,13 +71,13 @@ public final class NotPredicate implements Predicate, Serializable {
     }
 
     /**
-     * Gets the predicate.
+     * Gets the predicate being decorated.
      * 
-     * @return the predicate
+     * @return the predicate as the only element in an array
      * @since Commons Collections 3.1
      */
-    public Predicate getPredicate() {
+    public Predicate[] getPredicates() {
-        return iPredicate;
+        return new Predicate[] {iPredicate};
     }
 
 }

src/java/org/apache/commons/collections/functors/NullIsExceptionPredicate.java

@@ -24,11 +24,11 @@ import org.apache.commons.collections.Predicate;
  * Predicate implementation that throws an exception if the input is null.
  * 
  * @since Commons Collections 3.0
- * @version $Revision: 1.6 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.7 $ $Date: 2004/05/31 16:43:17 $
  *
  * @author Stephen Colebourne
  */
-public final class NullIsExceptionPredicate implements Predicate, Serializable {
+public final class NullIsExceptionPredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = 3243449850504576071L;
@@ -77,13 +77,13 @@ public final class NullIsExceptionPredicate implements Predicate, Serializable {
     }
 
     /**
-     * Gets the predicate.
+     * Gets the predicate being decorated.
      * 
-     * @return the predicate
+     * @return the predicate as the only element in an array
      * @since Commons Collections 3.1
      */
-    public Predicate getPredicate() {
+    public Predicate[] getPredicates() {
-        return iPredicate;
+        return new Predicate[] {iPredicate};
     }
 
 }

src/java/org/apache/commons/collections/functors/NullIsFalsePredicate.java

@@ -23,11 +23,11 @@ import org.apache.commons.collections.Predicate;
  * Predicate implementation that returns false if the input is null.
  * 
  * @since Commons Collections 3.0
- * @version $Revision: 1.5 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.6 $ $Date: 2004/05/31 16:43:17 $
  *
  * @author Stephen Colebourne
  */
-public final class NullIsFalsePredicate implements Predicate, Serializable {
+public final class NullIsFalsePredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = -2997501534564735525L;
@@ -75,13 +75,13 @@ public final class NullIsFalsePredicate implements Predicate, Serializable {
     }
 
     /**
-     * Gets the predicate.
+     * Gets the predicate being decorated.
      * 
-     * @return the predicate
+     * @return the predicate as the only element in an array
      * @since Commons Collections 3.1
      */
-    public Predicate getPredicate() {
+    public Predicate[] getPredicates() {
-        return iPredicate;
+        return new Predicate[] {iPredicate};
     }
 
 }

src/java/org/apache/commons/collections/functors/NullIsTruePredicate.java

@@ -23,11 +23,11 @@ import org.apache.commons.collections.Predicate;
  * Predicate implementation that returns true if the input is null.
  * 
  * @since Commons Collections 3.0
- * @version $Revision: 1.5 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.6 $ $Date: 2004/05/31 16:43:17 $
  *
  * @author Stephen Colebourne
  */
-public final class NullIsTruePredicate implements Predicate, Serializable {
+public final class NullIsTruePredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = -7625133768987126273L;
@@ -75,13 +75,13 @@ public final class NullIsTruePredicate implements Predicate, Serializable {
     }
 
     /**
-     * Gets the predicate.
+     * Gets the predicate being decorated.
      * 
-     * @return the predicate
+     * @return the predicate as the only element in an array
      * @since Commons Collections 3.1
      */
-    public Predicate getPredicate() {
+    public Predicate[] getPredicates() {
-        return iPredicate;
+        return new Predicate[] {iPredicate};
     }
 
 }

src/java/org/apache/commons/collections/functors/OnePredicate.java

@@ -24,11 +24,11 @@ import org.apache.commons.collections.Predicate;
  * Predicate implementation that returns true if only one of the predicates return true.
  * 
  * @since Commons Collections 3.0
- * @version $Revision: 1.5 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.6 $ $Date: 2004/05/31 16:43:17 $
  *
  * @author Stephen Colebourne
  */
-public final class OnePredicate implements Predicate, Serializable {
+public final class OnePredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = -8125389089924745785L;

src/java/org/apache/commons/collections/functors/OrPredicate.java

@@ -23,11 +23,11 @@ import org.apache.commons.collections.Predicate;
  * Predicate implementation that returns true if either of the predicates return true.
  * 
  * @since Commons Collections 3.0
- * @version $Revision: 1.5 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.6 $ $Date: 2004/05/31 16:43:17 $
  *
  * @author Stephen Colebourne
  */
-public final class OrPredicate implements Predicate, Serializable {
+public final class OrPredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = -8791518325735182855L;
@@ -76,22 +76,13 @@ public final class OrPredicate implements Predicate, Serializable {
     }
 
     /**
-     * Gets the first predicate.
+     * Gets the two predicates being decorated as an array.
      * 
-     * @return the predicate
+     * @return the predicates
      * @since Commons Collections 3.1
      */
-    public Predicate getPredicate1() {
+    public Predicate[] getPredicates() {
-        return iPredicate1;
+        return new Predicate[] {iPredicate1, iPredicate2};
-    }
-
-    /**
-     * Gets the second predicate.
-     * @return the predicate
-     * @since Commons Collections 3.1
-     */
-    public Predicate getPredicate2() {
-        return iPredicate2;
     }
 
 }

src/java/org/apache/commons/collections/functors/PredicateDecorator.java

@@ -0,0 +1,42 @@
+/*
+ *  Copyright 2004 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.commons.collections.functors;
+
+import org.apache.commons.collections.Predicate;
+
+/**
+ * Defines a predicate that decorates one or more other predicates.
+ * <p>
+ * This interface enables tools to access the decorated predicates.
+ * 
+ * @since Commons Collections 3.1
+ * @version $Revision: 1.1 $ $Date: 2004/05/31 16:43:17 $
+ * 
+ * @author Stephen Colebourne
+ */
+public interface PredicateDecorator extends Predicate {
+
+    /**
+     * Gets the predicates being decorated as an array.
+     * <p>
+     * The array may be the internal data structure of the predicate and thus
+     * should not be altered.
+     * 
+     * @return the predicates being decorated
+     */
+    Predicate[] getPredicates();
+
+}

src/java/org/apache/commons/collections/functors/TransformedPredicate.java

@@ -25,11 +25,11 @@ import org.apache.commons.collections.Transformer;
  * another <code>Predicate</code>.
  * 
  * @since Commons Collections 3.1
- * @version $Revision: 1.3 $ $Date: 2004/05/16 11:16:01 $
+ * @version $Revision: 1.4 $ $Date: 2004/05/31 16:43:17 $
  * @author Alban Peignier
  * @author Stephen Colebourne
  */
-public final class TransformedPredicate implements Predicate, Serializable {
+public final class TransformedPredicate implements Predicate, PredicateDecorator, Serializable {
 
     /** Serial version UID */
     static final long serialVersionUID = -5596090919668315834L;
@@ -82,12 +82,13 @@ public final class TransformedPredicate implements Predicate, Serializable {
     }
 
     /**
-     * Gets the predicate in use.
+     * Gets the predicate being decorated.
      * 
-     * @return the predicate
+     * @return the predicate as the only element in an array
+     * @since Commons Collections 3.1
      */
-    public Predicate getPredicate() {
+    public Predicate[] getPredicates() {
-        return iPredicate;
+        return new Predicate[] {iPredicate};
     }
 
     /**