001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.release.plugin.velocity;
018
019import java.io.Writer;
020
021import org.apache.commons.lang3.StringUtils;
022import org.apache.velocity.Template;
023import org.apache.velocity.VelocityContext;
024import org.apache.velocity.app.VelocityEngine;
025import org.apache.velocity.runtime.RuntimeConstants;
026import org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader;
027
028/**
029 * This class' purpose is to generate the <code>README.html</code> that moves along with the
030 * release for the sake of downloading the release from the distribution area.
031 *
032 * @since 1.3
033 */
034public class ReadmeHtmlVelocityDelegate {
035    /**
036     * A builder class for instantiation of the {@link ReadmeHtmlVelocityDelegate}.
037     */
038    public static class ReadmeHtmlVelocityDelegateBuilder {
039        /** The maven artifactId to use in the <code>README.vm</code> template. */
040        private String artifactId;
041        /** The maven version to use in the <code>README.vm</code> template. */
042        private String version;
043        /** The site url to use in the <code>README.vm</code> template. */
044        private String siteUrl;
045
046        /**
047         * Private constructor for using the builder through the {@link ReadmeHtmlVelocityDelegate#builder()}
048         * method.
049         */
050        private ReadmeHtmlVelocityDelegateBuilder() {
051        }
052
053        /**
054         * Builds up the {@link ReadmeHtmlVelocityDelegate} from the previously set parameters.
055         * @return a new {@link ReadmeHtmlVelocityDelegate}.
056         */
057        public ReadmeHtmlVelocityDelegate build() {
058            return new ReadmeHtmlVelocityDelegate(this.artifactId, this.version, this.siteUrl);
059        }
060
061        /**
062         * Adds the artifactId to the {@link ReadmeHtmlVelocityDelegate}.
063         * @param artifactId the {@link String} representing the maven artifactId.
064         * @return the builder to continue building.
065         */
066        public ReadmeHtmlVelocityDelegateBuilder withArtifactId(final String artifactId) {
067            this.artifactId = artifactId;
068            return this;
069        }
070
071        /**
072         * Adds the siteUrl to the {@link ReadmeHtmlVelocityDelegate}.
073         * @param siteUrl the site url to be used in the <code>README.html</code>
074         * @return the builder to continue building.
075         */
076        public ReadmeHtmlVelocityDelegateBuilder withSiteUrl(final String siteUrl) {
077            this.siteUrl = siteUrl;
078            return this;
079        }
080
081        /**
082         * Adds the version to the {@link ReadmeHtmlVelocityDelegate}.
083         * @param version the maven version.
084         * @return the builder to continue building.
085         */
086        public ReadmeHtmlVelocityDelegateBuilder withVersion(final String version) {
087            this.version = version;
088            return this;
089        }
090    }
091    /** The location of the velocity template for this class. */
092    private static final String TEMPLATE = "resources/org/apache/commons/release/plugin"
093                                         + "/velocity/README.vm";
094    /**
095     * Gets the {@link ReadmeHtmlVelocityDelegateBuilder} for constructing the {@link ReadmeHtmlVelocityDelegate}.
096     *
097     * @return the {@link ReadmeHtmlVelocityDelegateBuilder}.
098     */
099    public static ReadmeHtmlVelocityDelegateBuilder builder() {
100        return new ReadmeHtmlVelocityDelegateBuilder();
101    }
102    /** This is supposed to represent the maven artifactId. */
103    private final String artifactId;
104
105    /** This is supposed to represent the maven version of the release. */
106    private final String version;
107
108    /** The url of the site that gets set into the <code>README.html</code>. */
109    private final String siteUrl;
110
111    /**
112     * The private constructor to be used by the {@link ReadmeHtmlVelocityDelegateBuilder}.
113     *
114     * @param artifactId sets the {@link ReadmeHtmlVelocityDelegate#artifactId}.
115     * @param version sets the {@link ReadmeHtmlVelocityDelegate#version}.
116     * @param siteUrl sets the {@link ReadmeHtmlVelocityDelegate#siteUrl}.
117     */
118    private ReadmeHtmlVelocityDelegate(final String artifactId, final String version, final String siteUrl) {
119        this.artifactId = artifactId;
120        this.version = version;
121        this.siteUrl = siteUrl;
122    }
123
124    /**
125     * Renders the <code>README.vm</code> velocity template with the variables constructed with the
126     * {@link ReadmeHtmlVelocityDelegateBuilder}.
127     *
128     * @param writer is the {@link Writer} to which we wish to render the <code>README.vm</code> template.
129     * @return a reference to the {@link Writer} passed in.
130     */
131    public Writer render(final Writer writer) {
132        final VelocityEngine ve = new VelocityEngine();
133        ve.setProperty(RuntimeConstants.RESOURCE_LOADER, "classpath");
134        ve.setProperty("classpath.resource.loader.class", ClasspathResourceLoader.class.getName());
135        ve.init();
136        final Template template = ve.getTemplate(TEMPLATE);
137        final String[] splitArtifactId = artifactId.split("-");
138        final String wordCommons = "commons";
139        String artifactShortName = "";
140        if (splitArtifactId.length > 1) {
141            artifactShortName = splitArtifactId[1];
142        } else if (splitArtifactId.length == 1) {
143            artifactShortName = splitArtifactId[0];
144        }
145        // ".+\\d$" matches a non-empty string that terminates in a digit {0-9}.
146        if (artifactShortName.matches(".+\\d$")) {
147            artifactShortName = artifactShortName.substring(0, artifactShortName.length() - 1);
148        }
149        final String artifactIdWithFirstLetterscapitalized =
150                StringUtils.capitalize(wordCommons)
151                        + "-"
152                        + artifactShortName.toUpperCase();
153        final VelocityContext context = new VelocityContext();
154        context.internalPut("artifactIdWithFirstLetterscapitalized", artifactIdWithFirstLetterscapitalized);
155        context.internalPut("artifactShortName", artifactShortName.toUpperCase());
156        context.internalPut("artifactId", artifactId);
157        context.internalPut("version", version);
158        context.internalPut("siteUrl", siteUrl);
159        template.merge(context, writer);
160        return writer;
161    }
162}