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1   /*
2    * (c) Copyright 2006-2020 by rapiddweller GmbH & Volker Bergmann. All rights reserved.
3    *
4    * Redistribution and use in source and binary forms, with or without
5    * modification, is permitted under the terms of the
6    * GNU General Public License.
7    *
8    * For redistributing this software or a derivative work under a license other
9    * than the GPL-compatible Free Software License as defined by the Free
10   * Software Foundation or approved by OSI, you must first obtain a commercial
11   * license to this software product from rapiddweller GmbH & Volker Bergmann.
12   *
13   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
14   * WITHOUT A WARRANTY OF ANY KIND. ALL EXPRESS OR IMPLIED CONDITIONS,
15   * REPRESENTATIONS AND WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF
16   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE
17   * HEREBY EXCLUDED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
18   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
19   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
20   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
21   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
22   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
23   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24   * POSSIBILITY OF SUCH DAMAGE.
25   */
26  
27  package com.rapiddweller.benerator.engine.expression;
28  
29  import com.rapiddweller.common.Context;
30  import com.rapiddweller.format.script.Script;
31  import com.rapiddweller.format.script.ScriptUtil;
32  import com.rapiddweller.script.Expression;
33  import com.rapiddweller.script.expression.ConstantExpression;
34  import com.rapiddweller.script.expression.DynamicExpression;
35  
36  /**
37   * Expression that evaluates a script.<br/><br/>
38   * Created: 27.10.2009 13:48:11
39   *
40   * @param <E> the type parameter
41   * @author Volker Bergmann
42   * @since 0.6.0
43   */
44  public class ScriptExpression<E> extends DynamicExpression<E> {
45  
46    private final Script script;
47    private final Expression<E> defaultValueExpression;
48  
49    /**
50     * Instantiates a new Script expression.
51     *
52     * @param script the script
53     */
54    public ScriptExpression(String script) {
55      this(ScriptUtil.parseScriptText(script), (E) null);
56    }
57  
58    /**
59     * Instantiates a new Script expression.
60     *
61     * @param script the script
62     */
63    public ScriptExpression(Script script) {
64      this(script, (E) null);
65    }
66  
67    /**
68     * Instantiates a new Script expression.
69     *
70     * @param script       the script
71     * @param defaultValue the default value
72     */
73    public ScriptExpression(Script script, E defaultValue) {
74      this(script, (defaultValue != null ? new ConstantExpression<>(defaultValue) : null));
75    }
76  
77    private ScriptExpression(Script script, Expression<E> defaultValueExpression) {
78      this.script = script;
79      this.defaultValueExpression = defaultValueExpression;
80    }
81  
82    /**
83     * Create with default expression expression.
84     *
85     * @param <T>                    the type parameter
86     * @param script                 the script
87     * @param defaultValueExpression the default value expression
88     * @return the expression
89     */
90    public static <T> Expression<T> createWithDefaultExpression(
91        Script script, Expression<T> defaultValueExpression) {
92      return new ScriptExpression<>(script, defaultValueExpression);
93    }
94  
95    @Override
96    @SuppressWarnings("unchecked")
97    public E evaluate(Context context) {
98      if (script == null) {
99        return (defaultValueExpression != null ? defaultValueExpression.evaluate(context) : null);
100     } else {
101       return (E) script.evaluate(context);
102     }
103   }
104 
105   @Override
106   public String toString() {
107     return script.toString();
108   }
109 
110 }