YANG Translator optimization

Change-Id: Ie6a6b9d371a4fc5fd973cf56d6f3c7b44a3146ba
diff --git a/src/main/java/org/onosproject/yangutils/translator/tojava/JavaCodeGeneratorUtil.java b/src/main/java/org/onosproject/yangutils/translator/tojava/JavaCodeGeneratorUtil.java
new file mode 100644
index 0000000..40fed6e
--- /dev/null
+++ b/src/main/java/org/onosproject/yangutils/translator/tojava/JavaCodeGeneratorUtil.java
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2016 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.translator.tojava;
+
+import java.io.IOException;
+
+import org.onosproject.yangutils.datamodel.YangNode;
+
+/**
+ * Implementation of Java code generator based on application schema.
+ */
+public final class JavaCodeGeneratorUtil {
+
+    /**
+     * Default constructor.
+     */
+    private JavaCodeGeneratorUtil() {
+    }
+
+    /**
+     * Generate Java code files corresponding to the YANG schema.
+     *
+     * @param rootNode root node of the data model tree
+     * @param codeGenDir code generation directory
+     * @throws IOException when fails to generate java code file the current
+     *             node
+     */
+    public static void generateJavaCode(YangNode rootNode, String codeGenDir) throws IOException {
+        YangNode curNode = rootNode;
+        TraversalType curTraversal = TraversalType.ROOT;
+
+        while (!(curNode == null)) {
+            if (curTraversal != TraversalType.PARENT) {
+                generateCodeEntry(curNode, codeGenDir);
+            }
+            if (curTraversal != TraversalType.PARENT && curNode.getChild() != null) {
+                curTraversal = TraversalType.CHILD;
+                curNode = curNode.getChild();
+            } else if (curNode.getNextSibling() != null) {
+                generateCodeExit(curNode);
+                curTraversal = TraversalType.SIBILING;
+                curNode = curNode.getNextSibling();
+            } else {
+                generateCodeExit(curNode);
+                curTraversal = TraversalType.PARENT;
+                curNode = curNode.getParent();
+            }
+        }
+    }
+
+    /**
+     * Generates the current nodes code snippet.
+     *
+     * @param curNode current data model node for which the code needs to be
+     *            generated
+     * @param codeGenDir the base directory where the code needs to be generated
+     * @throws IOException IO operation exception
+     */
+    private static void generateCodeEntry(YangNode curNode,
+            String codeGenDir) throws IOException {
+
+        if (curNode instanceof JavaCodeGenerator) {
+            ((JavaCodeGenerator) curNode).generateCodeEntry(codeGenDir);
+        } else {
+            throw new RuntimeException(
+                    "Gnenerated data model node cannot be translated to target language code");
+        }
+    }
+
+    /**
+     * Generates the current nodes code target code from the snippet.
+     *
+     * @param curNode current data model node for which the code needs to be
+     *            generated
+     * @throws IOException IO operation exception
+     */
+    private static void generateCodeExit(YangNode curNode) throws IOException {
+
+        if (curNode instanceof JavaCodeGenerator) {
+            ((JavaCodeGenerator) curNode).generateCodeExit();
+        } else {
+            throw new RuntimeException(
+                    "Gnenerated data model node cannot be translated to target language code");
+        }
+    }
+}