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Diffstat (limited to 'framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/util/regexp/RegexpMatcherFactory.java')
-rw-r--r-- | framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/util/regexp/RegexpMatcherFactory.java | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/util/regexp/RegexpMatcherFactory.java b/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/util/regexp/RegexpMatcherFactory.java new file mode 100644 index 00000000..a0a8a155 --- /dev/null +++ b/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/util/regexp/RegexpMatcherFactory.java @@ -0,0 +1,114 @@ +/* + * 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.tools.ant.util.regexp; + +import org.apache.tools.ant.BuildException; +import org.apache.tools.ant.MagicNames; +import org.apache.tools.ant.Project; +import org.apache.tools.ant.util.ClasspathUtils; + +/** + * Simple Factory Class that produces an implementation of RegexpMatcher based on the system + * property <code>ant.regexp.regexpimpl</code> and the classes available. + * + * <p> + * In a more general framework this class would be abstract and have a static newInstance method. + * </p> + * + */ +public class RegexpMatcherFactory { + + /** Constructor for RegexpMatcherFactory. */ + public RegexpMatcherFactory() { + } + + /*** + * Create a new regular expression instance. + * @return the matcher + * @throws BuildException on error + */ + public RegexpMatcher newRegexpMatcher() throws BuildException { + return newRegexpMatcher(null); + } + + /*** + * Create a new regular expression instance. + * + * @param p Project whose ant.regexp.regexpimpl property will be used. + * @return the matcher + * @throws BuildException on error + */ + public RegexpMatcher newRegexpMatcher(Project p) throws BuildException { + String systemDefault = null; + if (p == null) { + systemDefault = System.getProperty(MagicNames.REGEXP_IMPL); + } else { + systemDefault = p.getProperty(MagicNames.REGEXP_IMPL); + } + + if (systemDefault != null) { + return createInstance(systemDefault); + // TODO should we silently catch possible exceptions and try to + // load a different implementation? + } + + return new Jdk14RegexpMatcher(); + } + + /** + * Create an instance of a matcher from a classname. + * + * @param className a <code>String</code> value + * @return a <code>RegexpMatcher</code> value + * @exception BuildException if an error occurs + */ + protected RegexpMatcher createInstance(String className) throws BuildException { + return (RegexpMatcher) ClasspathUtils.newInstance(className, RegexpMatcherFactory.class + .getClassLoader(), RegexpMatcher.class); + } + + /** + * Test if a particular class is available to be used. + * + * @param className a <code>String</code> value + * @exception BuildException if an error occurs + */ + protected void testAvailability(String className) throws BuildException { + try { + Class.forName(className); + } catch (Throwable t) { + throw new BuildException(t); + } + } + + /** + * Checks if a RegExp-Matcher is available. + * @param project The project to check for (may be <code>null</code>) + * @return <code>true</code> if available otherwise <code>false</code> + */ + public static boolean regexpMatcherPresent(Project project) { + try { + // The factory throws a BuildException if no usable matcher + // cannot be instantiated. We dont need the matcher itself here. + new RegexpMatcherFactory().newRegexpMatcher(project); + return true; + } catch (Throwable ex) { + return false; + } + } +} |