From d27387dd974de254d516008c4c7a60df51dad1e9 Mon Sep 17 00:00:00 2001 From: Stephane Bailliez Date: Sun, 27 Jan 2002 14:07:18 +0000 Subject: [PATCH] Extract the classes from Enumerations. git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@270949 13f79535-47bb-0310-9956-ffa450edef68 --- .../optional/junit/CompoundEnumeration.java | 132 ++++++++++++++++++ 1 file changed, 132 insertions(+) create mode 100644 proposal/sandbox/junit/src/main/org/apache/tools/ant/taskdefs/optional/junit/CompoundEnumeration.java diff --git a/proposal/sandbox/junit/src/main/org/apache/tools/ant/taskdefs/optional/junit/CompoundEnumeration.java b/proposal/sandbox/junit/src/main/org/apache/tools/ant/taskdefs/optional/junit/CompoundEnumeration.java new file mode 100644 index 000000000..cbe23e457 --- /dev/null +++ b/proposal/sandbox/junit/src/main/org/apache/tools/ant/taskdefs/optional/junit/CompoundEnumeration.java @@ -0,0 +1,132 @@ +/* + * The Apache Software License, Version 1.1 + * + * Copyright (c) 2002 The Apache Software Foundation. All rights + * reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * + * 3. The end-user documentation included with the redistribution, if + * any, must include the following acknowlegement: + * "This product includes software developed by the + * Apache Software Foundation (http://www.apache.org/)." + * Alternately, this acknowlegement may appear in the software itself, + * if and wherever such third-party acknowlegements normally appear. + * + * 4. The names "The Jakarta Project", "Ant", and "Apache Software + * Foundation" must not be used to endorse or promote products derived + * from this software without prior written permission. For written + * permission, please contact apache@apache.org. + * + * 5. Products derived from this software may not be called "Apache" + * nor may "Apache" appear in their names without prior written + * permission of the Apache Group. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR + * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * ==================================================================== + * + * This software consists of voluntary contributions made by many + * individuals on behalf of the Apache Software Foundation. For more + * information on the Apache Software Foundation, please see + * . + */ +package org.apache.tools.ant.taskdefs.optional.junit; + +import java.util.Enumeration; +import java.util.NoSuchElementException; + +/** + * Convenient enumeration over an array of enumeration. For example: + * 
+ * Enumeration e1 = v1.elements();
+ * while (e1.hasMoreElements()){
+ *    // do something
+ * }
+ * Enumeration e2 = v2.elements();
+ * while (e2.hasMoreElements()){
+ *    // do the same thing
+ * }
+ *
+ * can be written as: + * 
+ * Enumeration[] enums = { v1.elements(), v2.elements() };
+ * Enumeration e = Enumerations.fromCompound(enums);
+ * while (e.hasMoreElements()){
+ *    // do something
+ * }
+ *
+ * Note that the enumeration will skip null elements in the array. The following is + * thus possible: + * 
+ * Enumeration[] enums = { v1.elements(), null, v2.elements() }; // a null enumeration in the array
+ * Enumeration e = Enumerations.fromCompound(enums);
+ * while (e.hasMoreElements()){
+ *    // do something
+ * }
+ *
+ * @author Stephane Bailliez + */ + class CompoundEnumeration implements Enumeration { + + /** enumeration array */ + private Enumeration[] enumArray; + + /** index in the enums array */ + private int index = 0; + + public CompoundEnumeration(Enumeration[] enumarray) { + this.enumArray = enumarray; + } + + /** + * Tests if this enumeration contains more elements. + * + * @return true if and only if this enumeration object + * contains at least one more element to provide; + * false otherwise. + */ + public boolean hasMoreElements() { + while (index < enumArray.length) { + if (enumArray[index] != null && enumArray[index].hasMoreElements()) { + return true; + } + index++; + } + return false; + } + + /** + * Returns the next element of this enumeration if this enumeration + * object has at least one more element to provide. + * + * @return the next element of this enumeration. + * @throws NoSuchElementException if no more elements exist. + */ + public Object nextElement() throws NoSuchElementException { + if ( hasMoreElements() ) { + return enumArray[index].nextElement(); + } + throw new NoSuchElementException(); + } +}