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Diffstat (limited to 'velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/node/MapGetExecutor.java')
-rw-r--r-- | velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/node/MapGetExecutor.java | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/node/MapGetExecutor.java b/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/node/MapGetExecutor.java new file mode 100644 index 00000000..2c9aaea5 --- /dev/null +++ b/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/node/MapGetExecutor.java @@ -0,0 +1,105 @@ +package org.apache.velocity.runtime.parser.node; + +/* + * 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. + */ + +import org.slf4j.Logger; + +import java.lang.reflect.Method; +import java.util.Map; + +/** + * GetExecutor that is smart about Maps. If it detects one, it does not + * use Reflection but a cast to access the getter. + * + * @author <a href="mailto:henning@apache.org">Henning P. Schmiedehausen</a> + * @version $Id$ + * @since 1.5 + */ +public class MapGetExecutor + extends AbstractExecutor +{ + private final String property; + private final boolean isAlive; + + public MapGetExecutor(final Logger log, final Object object, final String property) + { + this.log = log; + this.property = property; + isAlive = discover(object); + } + + @Override + public Method getMethod() + { + if (isAlive()) + { + return MapGetMethod.instance(); + } + return null; + } + + @Override + public boolean isAlive() + { + return isAlive; + } + + protected boolean discover (final Object object) + { + if (object instanceof Map) + { + if (property != null) + { + return true; + } + } + return false; + } + + @Override + public Object execute(final Object o) + { + return ((Map) o).get(property); + } + + private static final class MapGetMethod + { + private static final Method instance; + + static + { + try + { + instance = Map.class.getMethod("get", Object.class); + } + catch (final NoSuchMethodException mapGetMethodMissingError) + { + throw new Error(mapGetMethodMissingError); + } + } + + private MapGetMethod() { } + + static Method instance() + { + return instance; + } + } +} |