001    /**
002     * Copyright 2005-2014 The Kuali Foundation
003     *
004     * Licensed under the Educational Community License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     * http://www.opensource.org/licenses/ecl2.php
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    package org.kuali.rice.krms.api.engine;
017    
018    import java.util.Collections;
019    import java.util.HashMap;
020    import java.util.Map;
021    
022    import org.apache.commons.lang.StringUtils;
023    
024    /**
025     * The ExecutionOptions contain a set of options that can be passed to the KRMS
026     * engine to control certain aspects related to it's execution.  It supports
027     * two different types of options:
028     * 
029     * <ol>
030     *   <li>flags - a map of pre-defined boolean {@link ExecutionFlag} instances which can be either true or false</li>
031     *   <li>options - a general-purpose map of Strings which can be used to define optinos that have non-boolen values</li>
032     * </ol>
033     * 
034     * <p>The options map can be used to pass user-defined or provider-specific options.  The ExecutionOptions are made
035     * available as part of the {@link ExecutionEnvironment} during engine execution.
036     * 
037     * <p>Instances of ExecutionOptions are not safe for use by multiple threads.
038     * 
039     * @author Kuali Rice Team (rice.collab@kuali.org)
040     *
041     */
042    public final class ExecutionOptions {
043    
044            private final Map<ExecutionFlag, Boolean> flags;
045            private final Map<String, String> options;
046            
047            /**
048             * Construct an empty set of execution options.
049             */
050            public ExecutionOptions() {
051                    flags = new HashMap<ExecutionFlag, Boolean>();
052                    options = new HashMap<String, String>();
053            }
054            
055            /**
056             * Constructs a new set of execution options, initialized with all options
057             * and flags copied from the given set of execution options.
058             * 
059             * @param executionOptions the execution options from which to copy into the newly created instance.
060             * If the given execution options are null, then this constructor is equivalent to {@link ExecutionOptions#ExecutionOptions()}
061             */
062            public ExecutionOptions(ExecutionOptions executionOptions) {
063                    this();
064                    if (executionOptions != null) {
065                            this.flags.putAll(executionOptions.getFlags());
066                            this.options.putAll(executionOptions.getOptions());
067                    }
068            }
069            
070            /**
071             * Sets the value for the given flag to the given boolean value.
072             * 
073             * @param flag the flag to set
074             * @param value the flag value to set
075             * @return a reference to this object
076             * 
077             * @throws IllegalArgumentException if the given flag is null
078             */
079            public ExecutionOptions setFlag(ExecutionFlag flag, boolean value) {
080                    if (flag == null) {
081                            throw new IllegalArgumentException("flag was null");
082                    }
083                    flags.put(flag, value);
084                    return this;
085            }
086            
087            /**
088             * Sets the value for the given option name to the given value.
089             * 
090             * @param optionName the name of the option to set
091             * @param value the value of the option to set
092             * @return a reference to this object
093             * 
094             * @throws IllegalArgumentException if the given optionName is blank
095             */
096            public ExecutionOptions setOption(String optionName, String value) {
097                    if (StringUtils.isBlank(optionName)) {
098                            throw new IllegalArgumentException("optionName was blank");
099                    }
100                    options.put(optionName, value);
101                    return this;
102            }
103            
104            /**
105             * Removes the specified flag (if it has been set) from the set of execution options.
106             * If the flag is not currently set, this method will do nothing.
107             * 
108             * @param flag the flag to remove
109             * @return a reference to this object
110             * 
111             * @throws IllegalArgumentException if the given flag is null
112             */
113            public ExecutionOptions removeFlag(ExecutionFlag flag) {
114                    if (flag == null) {
115                            throw new IllegalArgumentException("flag was null");
116                    }
117                    flags.remove(flag);
118                    return this;
119            }
120            
121            /**
122             * Removes the option with the specified name (if it has been set) from the set
123             * of execution options.  If the option is not currently set, this method will
124             * do nothing.
125             * 
126             * @param optionName the name of the option to remove
127             * @return a reference to this object
128             * 
129             * @throws IllegalArgumentException if the given optionName is blank
130             */
131            public ExecutionOptions removeOption(String optionName) {
132                    if (StringUtils.isBlank(optionName)) {
133                            throw new IllegalArgumentException("optionName was blank");
134                    }
135                    options.remove(optionName);
136                    return this;
137            }
138            
139            /**
140             * Returns the value the given flag.  If the specified flag has not been set
141             * on this object, then {@link ExecutionFlag#getDefaultValue()} will be returned.
142             * 
143             * @param flag the flag to check
144             * @return the value of the flag, or the flag's default value if the flag value
145             * is not currently set on this object
146             * 
147             * @throws IllegalArgumentException if the given flag is null
148             */
149            public boolean getFlag(ExecutionFlag flag) {
150                    if (flag == null) {
151                            throw new IllegalArgumentException("flag is null");
152                    }
153                    if (isFlagSet(flag)) {
154                            return flags.get(flag).booleanValue();
155                    }
156                    return flag.getDefaultValue();
157            }
158            
159            /**
160             * Returns the value for the option with the given name, or null
161             * if the option is not set.
162             * 
163             * @param optionName the name of the option for which to retrieve the value
164             * @return the value of the option, or null if the option is not set
165             * 
166             * @throws IllegalArgumentException if the given optionName is blank
167             */
168            public String getOption(String optionName) {
169                    if (StringUtils.isBlank(optionName)) {
170                            throw new IllegalArgumentException("optionName is blank");
171                    }
172                    return options.get(optionName);
173            }
174            
175            /**
176             * Checks whether or not the given flag is set.
177             * 
178             * @param flag the flag to check
179             * @return true if the flag is set, false if not
180             * 
181             * @throws IllegalArgumentException if the given flag is null
182             */
183            public boolean isFlagSet(ExecutionFlag flag) {
184                    if (flag == null) {
185                            throw new IllegalArgumentException("flag is null");
186                    }
187                    return flags.containsKey(flag);
188            }
189            
190            /**
191             * Checks whether or not the option with the given name has been set.
192             * 
193             * @param optionName the name of the option to check
194             * @return true if the option is set, false if not
195             * 
196             * @throws IllegalArgumentException if the given optionName is blank
197             */
198            public boolean isOptionSet(String optionName) {
199                    if (StringUtils.isBlank(optionName)) {
200                            throw new IllegalArgumentException("optionName is blank");
201                    }
202                    return options.containsKey(optionName);
203            }
204    
205            /**
206             * Returns an immutable map of the flags that have been set on this object.
207             * 
208             * @return the flags that have been set, this map be empty but will never be null
209             */
210            public Map<ExecutionFlag, Boolean> getFlags() {
211                    return Collections.unmodifiableMap(new HashMap<ExecutionFlag, Boolean>(flags));
212            }
213    
214            /**
215             * Returns an immutable map of the options that have been set on this object.
216             * 
217             * @return the options that have been set, this map be empty but will never be null
218             */     
219            public Map<String, String> getOptions() {
220                    return Collections.unmodifiableMap(new HashMap<String, String>(options));
221            }
222            
223    }