| /* |
| * 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.commons.jexl3; |
| |
| import java.util.Collections; |
| import java.util.Map; |
| import org.apache.commons.jexl3.annotations.NoJexl; |
| |
| /** |
| * A JEXL evaluation environment wrapping variables, namespace and options. |
| */ |
| public class JexlEvalContext implements |
| JexlContext, |
| JexlContext.NamespaceResolver, |
| JexlContext.OptionsHandle { |
| /** The marker for the empty vars. */ |
| private static final Map<String,Object> EMPTY_MAP = Collections.<String,Object>emptyMap(); |
| /** The variables.*/ |
| private final JexlContext vars; |
| /** The namespace. */ |
| private final JexlContext.NamespaceResolver ns; |
| /** The options. */ |
| private final JexlOptions options = new JexlOptions(); |
| |
| /** |
| * Default constructor. |
| */ |
| @NoJexl |
| public JexlEvalContext() { |
| this(EMPTY_MAP); |
| } |
| |
| /** |
| * Creates an evaluation environment wrapping an existing user provided vars. |
| * <p>The supplied vars should be null only in derived classes that override the get/set/has methods. |
| * For a default vars context with a code supplied vars, use the default no-parameter contructor.</p> |
| * @param map the variables map |
| */ |
| @NoJexl |
| public JexlEvalContext(final Map<String, Object> map) { |
| this.vars = map == EMPTY_MAP ? new MapContext() : new MapContext(map); |
| this.ns = null; |
| } |
| |
| /** |
| * Creates an evaluation environment from a context. |
| * @param context the context (may be null, implies readonly) |
| */ |
| @NoJexl |
| public JexlEvalContext(final JexlContext context) { |
| this(context, context instanceof JexlContext.NamespaceResolver? (JexlContext.NamespaceResolver) context : null); |
| } |
| |
| /** |
| * Creates an evaluation environment from a context and a namespace. |
| * @param context the context (may be null, implies readonly) |
| * @param namespace the namespace (may be null, implies empty namespace) |
| */ |
| @NoJexl |
| public JexlEvalContext(final JexlContext context, final JexlContext.NamespaceResolver namespace) { |
| this.vars = context != null? context : JexlEngine.EMPTY_CONTEXT; |
| this.ns = namespace != null? namespace : JexlEngine.EMPTY_NS; |
| } |
| |
| @Override |
| @NoJexl |
| public boolean has(final String name) { |
| return vars.has(name); |
| } |
| |
| @Override |
| @NoJexl |
| public Object get(final String name) { |
| return vars.get(name); |
| } |
| |
| @Override |
| @NoJexl |
| public void set(final String name, final Object value) { |
| vars.set(name, value); |
| } |
| |
| @Override |
| @NoJexl |
| public Object resolveNamespace(final String name) { |
| return ns != null? ns.resolveNamespace(name) : null; |
| } |
| |
| @Override |
| @NoJexl |
| public JexlOptions getEngineOptions() { |
| return options; |
| } |
| |
| } |