PomGenerator.java

/**
 *
 */
package org.minnal.generator.core;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.OutputStreamWriter;
import java.util.HashSet;
import java.util.Set;

import org.apache.maven.model.Build;
import org.apache.maven.model.Dependency;
import org.apache.maven.model.Model;
import org.apache.maven.model.Plugin;
import org.apache.maven.model.PluginExecution;
import org.apache.maven.model.Repository;
import org.apache.maven.model.io.xpp3.MavenXpp3Reader;
import org.apache.maven.model.io.xpp3.MavenXpp3Writer;
import org.codehaus.plexus.util.xml.Xpp3Dom;
import org.minnal.generator.exception.MinnalGeneratorException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.base.Charsets;

/**
 * @author ganeshs
 */
public class PomGenerator extends AbstractGenerator {

    private String projectName;

    private Model model;

    private Set<Dependency> dependenciesToAdd = new HashSet<Dependency>();

    private Set<Dependency> dependenciesToRemove = new HashSet<Dependency>();

    private static final String MODEL_VERSION = "4.0.0";

    private static final String DEFAULT_VERSION = "0.0.1-SNAPSHOT";

    private static final String POM_FILE = "pom.xml";

    private static final String ACTIVE_JPA_RELEASES_REPO = "https://raw.github.com/ActiveJpa/activejpa/mvn-repo/releases";

    private static final String AUTOPOJO_RELEASES_REPO = "https://raw.github.com/minnal/mvn-repo/master/releases";

    private static final String MINNAL_RELEASES_REPO = "https://raw.github.com/minnal/mvn-repo/master/releases";

    private static final Logger logger = LoggerFactory.getLogger(PomGenerator.class);

    public PomGenerator(File baseDir, String projectName) {
        super(baseDir);
        this.projectName = projectName;
    }

    @Override
    public void init() {
        super.init();
        File pom = new File(baseDir, POM_FILE);
        if (pom.exists()) {
            logger.trace("pom already exist. Reading it");

            MavenXpp3Reader reader = new MavenXpp3Reader();
            FileInputStream stream = null;
            try {
                stream = new FileInputStream(pom);
                model = reader.read(stream);
            } catch (Exception e) {
                throw new MinnalGeneratorException("Failed while reading the pom - " + pom.getName(), e);
            } finally {
                closeStream(stream);
            }
        } else {
            model = createMavenModel();
        }
        for (Dependency dependency : dependenciesToAdd) {
            if (!model.getDependencies().contains(dependency)) {
                model.addDependency(dependency);
            }
        }
        for (Dependency dependency : dependenciesToRemove) {
            model.removeDependency(dependency);
        }
    }

    private Model createMavenModel() {
        model = new Model();
        model.setArtifactId(projectName);
        model.setName(projectName);
        model.setModelVersion(MODEL_VERSION);
        model.setVersion(DEFAULT_VERSION);
        model.setGroupId("com." + projectName.toLowerCase());

        Repository repository = new Repository();
        repository.setId("activejpa-repo");
        repository.setUrl(ACTIVE_JPA_RELEASES_REPO);
        model.addRepository(repository);

        repository = new Repository();
        repository.setId("autopojo-repo");
        repository.setUrl(AUTOPOJO_RELEASES_REPO);
        model.addRepository(repository);

        repository = new Repository();
        repository.setId("minnal-repo");
        repository.setUrl(MINNAL_RELEASES_REPO);
        model.addRepository(repository);

        Build build = new Build();
        Plugin plugin = new Plugin();
        plugin.setGroupId("org.codehaus.mojo");
        plugin.setArtifactId("exec-maven-plugin");
        plugin.setVersion("1.3.2");

        Xpp3Dom configuration = new Xpp3Dom("configuration");
        Xpp3Dom executable = new Xpp3Dom("executable");
        executable.setValue("java");
        configuration.addChild(executable);
        Xpp3Dom arguments = new Xpp3Dom("arguments");
        Xpp3Dom classpath = new Xpp3Dom("argument");
        Xpp3Dom classpathScope = new Xpp3Dom("classpathScope");
        classpath.setValue("-classpath");
        arguments.addChild(classpath);
        arguments.addChild(new Xpp3Dom("classpath"));
        Xpp3Dom mainClass = new Xpp3Dom("argument");
        mainClass.setValue("${mainClass}");
        arguments.addChild(mainClass);
        classpathScope.setValue("compile");
        configuration.addChild(arguments);
        configuration.addChild(classpathScope);
        plugin.setConfiguration(configuration);
        PluginExecution execution = new PluginExecution();
        execution.addGoal("java");
        plugin.addExecution(execution);

        build.addPlugin(plugin);
        model.setBuild(build);

        return model;
    }

    public void addDependency(String groupId, String artifactId, String version) {
        addDependency(groupId, artifactId, version, "compile");
    }

    public void addDependency(String groupId, String artifactId, String version, String scope) {
        Dependency dependency = new Dependency();
        dependency.setArtifactId(artifactId);
        dependency.setGroupId(groupId);
        dependency.setVersion(version);
        dependency.setScope(scope);
        dependenciesToAdd.add(dependency);
    }

    @Override
    public void generate() {
        logger.info("Creating the pom file {}", POM_FILE);
        File pom = new File(baseDir, POM_FILE);
        OutputStreamWriter fileWriter = null;
        try {
            fileWriter = new OutputStreamWriter(new FileOutputStream(pom), Charsets.UTF_8);
            logger.debug("Writing the generated pom file {}", POM_FILE);
            MavenXpp3Writer writer = new MavenXpp3Writer();
            writer.write(fileWriter, model);
        } catch (Exception e) {
            throw new MinnalGeneratorException("Failed while writing the pom - " + pom.getName(), e);
        } finally {
            closeStream(fileWriter);
        }
    }

}