[ONOS-4350] Inter Jar dependency implementation and code restructuring.

Change-Id: Iacac75e4187aed93ce1754c170a9c19707e5b8c3
diff --git a/utils/yangutils/plugin/src/main/java/org/onosproject/yangutils/plugin/manager/YangUtilManager.java b/utils/yangutils/plugin/src/main/java/org/onosproject/yangutils/plugin/manager/YangUtilManager.java
new file mode 100644
index 0000000..9339e4b
--- /dev/null
+++ b/utils/yangutils/plugin/src/main/java/org/onosproject/yangutils/plugin/manager/YangUtilManager.java
@@ -0,0 +1,374 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.yangutils.plugin.manager;
+
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Set;
+
+import org.apache.maven.artifact.repository.ArtifactRepository;
+import org.apache.maven.plugin.AbstractMojo;
+import org.apache.maven.plugin.MojoExecutionException;
+import org.apache.maven.plugin.MojoFailureException;
+import org.apache.maven.plugins.annotations.Component;
+import org.apache.maven.plugins.annotations.Mojo;
+import org.apache.maven.plugins.annotations.Parameter;
+import org.apache.maven.project.MavenProject;
+import org.onosproject.yangutils.datamodel.YangNode;
+import org.onosproject.yangutils.linker.YangLinker;
+import org.onosproject.yangutils.linker.exceptions.LinkerException;
+import org.onosproject.yangutils.linker.impl.YangLinkerManager;
+import org.onosproject.yangutils.parser.YangUtilsParser;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+import org.onosproject.yangutils.parser.impl.YangUtilsParserManager;
+import org.onosproject.yangutils.translator.tojava.utils.YangPluginConfig;
+import org.onosproject.yangutils.translator.tojava.utils.YangToJavaNamingConflictUtil;
+import org.onosproject.yangutils.utils.io.impl.YangFileScanner;
+import org.sonatype.plexus.build.incremental.BuildContext;
+
+import static org.apache.maven.plugins.annotations.LifecyclePhase.GENERATE_SOURCES;
+import static org.apache.maven.plugins.annotations.ResolutionScope.COMPILE;
+import static org.onosproject.yangutils.translator.tojava.JavaCodeGeneratorUtil.generateJavaCode;
+import static org.onosproject.yangutils.translator.tojava.JavaCodeGeneratorUtil.translatorErrorHandler;
+import static org.onosproject.yangutils.translator.tojava.utils.JavaIdentifierSyntax.getPackageDirPathFromJavaJPackage;
+import static org.onosproject.yangutils.utils.UtilConstants.DEFAULT_BASE_PKG;
+import static org.onosproject.yangutils.utils.UtilConstants.NEW_LINE;
+import static org.onosproject.yangutils.utils.UtilConstants.SLASH;
+import static org.onosproject.yangutils.utils.io.impl.YangIoUtils.addToCompilationRoot;
+import static org.onosproject.yangutils.utils.io.impl.YangIoUtils.copyYangFilesToTarget;
+import static org.onosproject.yangutils.utils.io.impl.YangIoUtils.deleteDirectory;
+import static org.onosproject.yangutils.utils.io.impl.YangIoUtils.getDirectory;
+import static org.onosproject.yangutils.utils.io.impl.YangIoUtils.resolveInterJarDependencies;
+import static org.onosproject.yangutils.utils.io.impl.YangIoUtils.serializeDataModel;
+
+/**
+ * Represents ONOS YANG utility maven plugin.
+ * Goal of plugin is yang2java.
+ * Execution phase is generate-sources.
+ * requiresDependencyResolution at compile time.
+ */
+@Mojo(name = "yang2java", defaultPhase = GENERATE_SOURCES, requiresDependencyResolution = COMPILE,
+    requiresProject = true)
+public class YangUtilManager
+        extends AbstractMojo {
+
+    private YangNode rootNode;
+    // YANG file information set.
+    private Set<YangFileInfo> yangFileInfoSet = new HashSet<>();
+    private YangUtilsParser yangUtilsParser = new YangUtilsParserManager();
+    private YangLinker yangLinker = new YangLinkerManager();
+    private YangFileInfo curYangFileInfo = new YangFileInfo();
+
+    private static final String DEFAULT_PKG = SLASH + getPackageDirPathFromJavaJPackage(DEFAULT_BASE_PKG);
+
+    /**
+     * Source directory for YANG files.
+     */
+    @Parameter(property = "yangFilesDir", defaultValue = "src/main/yang")
+    private String yangFilesDir;
+
+    /**
+     * Source directory for generated files.
+     */
+    @Parameter(property = "genFilesDir", defaultValue = "src/main/java")
+    private String genFilesDir;
+
+    /**
+     * Base directory for project.
+     */
+    @Parameter(property = "basedir", defaultValue = "${basedir}")
+    private String baseDir;
+
+    /**
+     * Output directory.
+     */
+    @Parameter(property = "project.build.outputDirectory", required = true, defaultValue = "target/classes")
+    private String outputDirectory;
+
+    /**
+     * Current maven project.
+     */
+    @Parameter(property = "project", required = true, readonly = true, defaultValue = "${project}")
+    private MavenProject project;
+
+    /**
+     * Replacement required for period special character in the identifier.
+     */
+    @Parameter(property = "replacementForPeriod")
+    private String replacementForPeriod;
+
+    /**
+     * Replacement required for underscore special character in the identifier.
+     */
+    @Parameter(property = "replacementForUnderscore")
+    private String replacementForUnderscore;
+
+    /**
+     * Replacement required for hyphen special character in the identifier.
+     */
+    @Parameter(property = "replacementForHyphen")
+    private String replacementForHyphen;
+
+    /**
+     * Prefix which is required for adding with the identifier.
+     */
+    @Parameter(property = "prefixForIdentifier")
+    private String prefixForIdentifier;
+
+    /**
+     * Build context.
+     */
+    @Component
+    private BuildContext context;
+
+    @Parameter(readonly = true, defaultValue = "${localRepository}")
+    private ArtifactRepository localRepository;
+
+    @Parameter(readonly = true, defaultValue = "${project.remoteArtifactRepositories}")
+    private List<ArtifactRepository> remoteRepository;
+
+    @Override
+    public void execute()
+            throws MojoExecutionException, MojoFailureException {
+
+        try {
+
+            /*
+             * For deleting the generated code in previous build.
+             */
+            deleteDirectory(getDirectory(baseDir, genFilesDir) + DEFAULT_PKG);
+            deleteDirectory(getDirectory(baseDir, outputDirectory));
+
+            String searchDir = getDirectory(baseDir, yangFilesDir);
+            String codeGenDir = getDirectory(baseDir, genFilesDir) + SLASH;
+
+            // Creates conflict resolver and set values to it.
+            YangToJavaNamingConflictUtil conflictResolver = new YangToJavaNamingConflictUtil();
+            conflictResolver.setReplacementForPeriod(replacementForPeriod);
+            conflictResolver.setReplacementForHyphen(replacementForHyphen);
+            conflictResolver.setReplacementForUnderscore(replacementForUnderscore);
+            conflictResolver.setPrefixForIdentifier(prefixForIdentifier);
+            YangPluginConfig yangPlugin = new YangPluginConfig();
+            yangPlugin.setCodeGenDir(codeGenDir);
+            yangPlugin.setConflictResolver(conflictResolver);
+
+            /*
+             * Obtain the YANG files at a path mentioned in plugin and creates
+             * YANG file information set.
+             */
+            createYangFileInfoSet(YangFileScanner.getYangFiles(searchDir));
+
+            // Check if there are any file to translate, if not return.
+            if (getYangFileInfoSet() == null || getYangFileInfoSet().isEmpty()) {
+                // No files to translate
+                return;
+            }
+            // Resolve inter jar dependency.
+            resolveInterJardependency();
+
+            // Carry out the parsing for all the YANG files.
+            parseYangFileInfoSet();
+
+            // Resolve dependencies using linker.
+            resolveDependenciesUsingLinker();
+
+            // Perform translation to JAVA.
+            translateToJava(getYangFileInfoSet(), yangPlugin);
+
+            // Serialize data model.
+            serializeDataModel(getDirectory(baseDir, outputDirectory), getYangFileInfoSet(), project, true);
+
+            addToCompilationRoot(getDirectory(baseDir, genFilesDir), project, context);
+
+            copyYangFilesToTarget(getYangFileInfoSet(), getDirectory(baseDir, outputDirectory), project);
+        } catch (IOException | ParserException e) {
+            getLog().info(e);
+            String fileName = "";
+            if (getCurYangFileInfo() != null) {
+                fileName = getCurYangFileInfo().getYangFileName();
+            }
+            try {
+                translatorErrorHandler(getRootNode());
+                deleteDirectory(getDirectory(baseDir, genFilesDir) + DEFAULT_PKG);
+            } catch (IOException ex) {
+                throw new MojoExecutionException(
+                        "Error handler failed to delete files for data model node.");
+            }
+            throw new MojoExecutionException(
+                    "Exception occured due to " + e.getLocalizedMessage() + " in " + fileName
+                            + " YANG file.");
+        }
+    }
+
+    /**
+     * Resolved inter-jar dependencies.
+     *
+     * @throws IOException when fails to do IO operations
+     */
+    public void resolveInterJardependency() throws IOException {
+        try {
+            List<YangNode> interJarResolvedNodes = resolveInterJarDependencies(project, localRepository,
+                    remoteRepository, getDirectory(baseDir, outputDirectory));
+            for (YangNode node : interJarResolvedNodes) {
+                YangFileInfo dependentFileInfo = new YangFileInfo();
+                dependentFileInfo.setRootNode(node);
+                dependentFileInfo.setForTranslator(false);
+                dependentFileInfo.setYangFileName(node.getName());
+                getYangFileInfoSet().add(dependentFileInfo);
+            }
+        } catch (IOException e) {
+            throw new IOException("failed to resolve in interjar scenario.");
+        }
+    }
+
+    /**
+     * Links all the provided with the YANG file info set.
+     *
+     * @throws MojoExecutionException a violation in mojo excecution
+     */
+    public void resolveDependenciesUsingLinker()
+            throws MojoExecutionException {
+        for (YangFileInfo yangFileInfo : getYangFileInfoSet()) {
+            setCurYangFileInfo(yangFileInfo);
+            try {
+                yangLinker.resolveDependencies(getYangFileInfoSet());
+            } catch (LinkerException e) {
+                throw new MojoExecutionException(e.getMessage());
+            }
+        }
+    }
+
+    /**
+     * Parses all the provided YANG files and generates YANG data model tree.
+     *
+     * @throws IOException a violation in IO
+     */
+    public void parseYangFileInfoSet()
+            throws IOException {
+        for (YangFileInfo yangFileInfo : getYangFileInfoSet()) {
+            setCurYangFileInfo(yangFileInfo);
+            if (yangFileInfo.isForTranslator()) {
+                try {
+                    YangNode yangNode = yangUtilsParser.getDataModel(yangFileInfo.getYangFileName());
+                    yangFileInfo.setRootNode(yangNode);
+                    setRootNode(yangNode);
+                } catch (ParserException e) {
+                    String logInfo = "Error in file: " + e.getFileName();
+                    if (e.getLineNumber() != 0) {
+                        logInfo = logInfo + " at line: " + e.getLineNumber() + " at position: "
+                                + e.getCharPositionInLine();
+
+                    }
+                    if (e.getMessage() != null) {
+                        logInfo = logInfo + NEW_LINE + e.getMessage();
+                    }
+                    getLog().info(logInfo);
+                    throw e;
+                }
+            }
+        }
+    }
+
+    /**
+     * Returns current root YANG node of data-model tree.
+     *
+     * @return current root YANG node of data-model tree
+     */
+    private YangNode getRootNode() {
+        return rootNode;
+    }
+
+    /**
+     * Sets current root YANG node of data-model tree.
+     *
+     * @param rootNode current root YANG node of data-model tree
+     */
+    private void setRootNode(YangNode rootNode) {
+        this.rootNode = rootNode;
+    }
+
+    /**
+     * Translates to java code corresponding to the YANG schema.
+     *
+     * @param yangFileInfoSet YANG file information
+     * @param yangPlugin      YANG plugin config
+     * @throws IOException when fails to generate java code file the current
+     *                     node
+     */
+    public void translateToJava(Set<YangFileInfo> yangFileInfoSet, YangPluginConfig yangPlugin)
+            throws IOException {
+        Iterator<YangFileInfo> yangFileIterator = yangFileInfoSet.iterator();
+        while (yangFileIterator.hasNext()) {
+            YangFileInfo yangFileInfo = yangFileIterator.next();
+            setCurYangFileInfo(yangFileInfo);
+            if (yangFileInfo.isForTranslator()) {
+                generateJavaCode(yangFileInfo.getRootNode(), yangPlugin);
+            }
+        }
+    }
+
+    /**
+     * Creates a YANG file info set.
+     *
+     * @param yangFileList YANG files list
+     */
+    public void createYangFileInfoSet(List<String> yangFileList) {
+        for (String yangFile : yangFileList) {
+            YangFileInfo yangFileInfo = new YangFileInfo();
+            yangFileInfo.setYangFileName(yangFile);
+            getYangFileInfoSet().add(yangFileInfo);
+        }
+    }
+
+    /**
+     * Returns the YANG file info set.
+     *
+     * @return the YANG file info set
+     */
+    public Set<YangFileInfo> getYangFileInfoSet() {
+        return yangFileInfoSet;
+    }
+
+    /**
+     * Sets the YANG file info set.
+     *
+     * @param yangFileInfoSet the YANG file info set
+     */
+    public void setYangFileInfoSet(Set<YangFileInfo> yangFileInfoSet) {
+        this.yangFileInfoSet = yangFileInfoSet;
+    }
+
+    /**
+     * Returns current YANG file's info.
+     *
+     * @return the yangFileInfo
+     */
+    public YangFileInfo getCurYangFileInfo() {
+        return curYangFileInfo;
+    }
+
+    /**
+     * Sets current YANG file's info.
+     *
+     * @param yangFileInfo the yangFileInfo to set
+     */
+    public void setCurYangFileInfo(YangFileInfo yangFileInfo) {
+        curYangFileInfo = yangFileInfo;
+    }
+}