1 package org.codehaus.modello.maven;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import java.io.File;
23 import java.util.Collections;
24 import java.util.List;
25 import java.util.Map;
26 import java.util.Properties;
27 import java.util.stream.Collectors;
28
29 import org.apache.maven.plugins.annotations.LifecyclePhase;
30 import org.apache.maven.plugins.annotations.Mojo;
31 import org.apache.maven.plugins.annotations.Parameter;
32 import org.codehaus.modello.plugin.velocity.VelocityGenerator;
33
34 /**
35 * Creates files from the model using Velocity templates.
36 * <p>
37 * This mojo can be given a list of templates and a list of parameters.
38 * Each template from the {@link #templates} property will be run with the following context:
39 * <ul>
40 * <li>{@code version}: the version of the model to generate</li>
41 * <li>{@code model}: the modello model</li>
42 * <li>{@code Helper}: a {@link org.codehaus.modello.plugin.velocity.Helper} object instance</li>
43 * <li>any additional parameters specified using the {@link #params} property</li>
44 * </ul>
45 * The output file is controlled from within the template using the {@code #MODELLO-VELOCITY#SAVE-OUTPUT-TO}
46 * <a href="https://velocity.apache.org/engine/2.3/vtl-reference.html#directives">VTL directive</a>.
47 * This allows a single template to generate multiple files. For example, the following
48 * directive will redirect further output from the template to a file named
49 * {@code org/apache/maven/api/model/Plugin.java} if the variable {@code package} is set to
50 * {@code org.apache.maven.api.model} and the variable {@code className} is set to {@code Plugin}.
51 * <p>
52 * {@code #MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java}
53 */
54 @Mojo(name = "velocity", defaultPhase = LifecyclePhase.GENERATE_SOURCES, threadSafe = true)
55 public class ModelloVelocityMojo extends AbstractModelloGeneratorMojo {
56 /**
57 * The output directory of the generated files.
58 */
59 @Parameter(defaultValue = "${project.build.directory}/generated-sources/modello")
60 private File outputDirectory;
61
62 /**
63 * The directory where Velocity templates are looked for.
64 */
65 @Parameter(defaultValue = "${project.basedir}")
66 private File velocityBasedir;
67
68 /**
69 * A list of template paths to be run against the loaded Modello model.
70 * Those are {@code .vm} files as described in the
71 * <a href="https://velocity.apache.org/engine/devel/user-guide.html">Velocity Users Guide</a>
72 * relative to {@code velocityBasedir}.
73 */
74 @Parameter
75 private List<String> templates;
76
77 /**
78 * A list of parameters, using the syntax {@code key=value}.
79 * Those parameters will be made accessible to the templates.
80 */
81 @Parameter
82 private List<String> params;
83
84 protected String getGeneratorType() {
85 return "velocity";
86 }
87
88 protected void customizeParameters(Properties parameters) {
89 super.customizeParameters(parameters);
90
91 Map<String, String> params = this.params == null
92 ? Collections.emptyMap()
93 : this.params.stream()
94 .collect(Collectors.toMap(
95 s -> s.substring(0, s.indexOf('=')), s -> s.substring(s.indexOf('=') + 1)));
96
97 parameters.put(VelocityGenerator.VELOCITY_BASEDIR, velocityBasedir.getAbsolutePath());
98
99 parameters.put(VelocityGenerator.VELOCITY_TEMPLATES, templates.stream().collect(Collectors.joining(",")));
100 parameters.put(VelocityGenerator.VELOCITY_PARAMETERS, params);
101 }
102
103 protected boolean producesCompilableResult() {
104 return true;
105 }
106
107 @Override
108 public File getOutputDirectory() {
109 return outputDirectory;
110 }
111 }