From 60018ae8c8c41b7aa7841db2f1e5f54c5c199728 Mon Sep 17 00:00:00 2001
From: "adrian.f.cole" <adrian.f.cole@3d8758e0-26b5-11de-8745-db77d3ebf521>
Date: Fri, 29 May 2009 10:10:17 +0000
Subject: [PATCH] Issue 36: changed to use classpath to load templates

git-svn-id: http://jclouds.googlecode.com/svn/trunk@870 3d8758e0-26b5-11de-8745-db77d3ebf521
---
 .../jclouds/codegen/util/CodeGenerator.java   | 267 +++++++++---------
 1 file changed, 126 insertions(+), 141 deletions(-)

diff --git a/codegen/src/main/java/org/jclouds/codegen/util/CodeGenerator.java b/codegen/src/main/java/org/jclouds/codegen/util/CodeGenerator.java
index 83ff899e05..91bb689e52 100644
--- a/codegen/src/main/java/org/jclouds/codegen/util/CodeGenerator.java
+++ b/codegen/src/main/java/org/jclouds/codegen/util/CodeGenerator.java
@@ -45,156 +45,141 @@ import freemarker.template.Template;
 import freemarker.template.TemplateException;
 
 /**
- * Converts object models representing AWS API beans into Java
- * classes. 
+ * Converts object models representing AWS API beans into Java classes.
  * <p>
  * This implementation is designed to perform the following steps:
  * <ul>
- * <li>Parse the JSON object representation produced by the <tt>parse_ec2.pl</tt> 
- *     perl script</li>
+ * <li>Parse the JSON object representation produced by the <tt>parse_ec2.pl</tt> perl script</li>
  * <li>Convert the JSON into Java object models (@see org.jclouds.aws.codegen.models)</li>
  * <li>Iterate through the Command objects generated above and with each one:
- *   <ul>
- *   <li>Load the <a href="http://freemarker.org/">FreeMarker</a>template file for the given 
- *       object</li>
- *   <li>Create a package directory to receive the Java file, if necessary</li>
- *   <li>Process the object through the template, producing a Java implementation of the object</li>
- *   <ul>
- * </li>
+ * <ul>
+ * <li>Load the <a href="http://freemarker.org/">FreeMarker</a>template file for the given object</li>
+ * <li>Create a package directory to receive the Java file, if necessary</li>
+ * <li>Process the object through the template, producing a Java implementation of the object</li>
+ * <ul></li>
  * 
  * @author James Murty
  */
 public class CodeGenerator {
-	public final static String COMMAND_TEMPLATE_FILENAME = "Command.ftl";
-	public final static String BEAN_TEMPLATE_FILENAME = "Bean.ftl";
-	
-	private final File templateDirectory;
-	private final File targetDirectory;
-	private final String rootPackageName;
-	private final Configuration config; 
-	
-	public CodeGenerator(String rootPackageName, File templateDirectory, File targetDirectory) 
-		throws IOException 
-	{
-		this.rootPackageName = rootPackageName;
-		this.templateDirectory = templateDirectory;
-		this.targetDirectory = targetDirectory;
-		
-		config = new Configuration();
-		config.setDirectoryForTemplateLoading(this.templateDirectory);
-	}
-	
-	/**
-	 * Parse a JSON object model file (as generated by
-	 * <tt>aws/src/main/bin/parse_ec2.pl</tt>) and convert
-	 * it into a Java object graph. 
-	 * 
-	 * @param objectModelFile
-	 * @return
-	 * @throws JsonParseException
-	 * @throws FileNotFoundException
-	 */
-	public Model parseModelFromJSON(File objectModelFile) 
-		throws JsonParseException, FileNotFoundException 
-	{
-		Gson gson = new Gson();
-		return gson.fromJson(new FileReader(objectModelFile), Model.class);				
-	}
-	
-	/**
-	 * Parse a JSON object model file and iterate over the resulting
-	 * objects generating Java code files.
-	 * 
-	 * @param objectModelFile
-	 * @throws JsonParseException
-	 * @throws IOException
-	 * @throws TemplateException
-	 */
-	public void generateCode(File objectModelFile) 
-		throws JsonParseException, IOException, TemplateException 
-	{
-		Model model = parseModelFromJSON(objectModelFile);
-		
-		for (Package pkg: model.getPackages()) {
-			for (Command command: pkg.getCommands()) {
-				generateClassFile(command, COMMAND_TEMPLATE_FILENAME);
-				
-				if (command.getHandler() != null) {
-					generateClassFile(command.getHandler(), BEAN_TEMPLATE_FILENAME);
-				}
-				if (command.getOptions() != null) {
-					generateClassFile(command.getOptions(), BEAN_TEMPLATE_FILENAME);					
-				}
-				if (command.getResponse() != null) {
-					generateClassFile(command.getResponse(), BEAN_TEMPLATE_FILENAME);					
-				}
-			}
-		}
-	}
-	
-	/**
-	 * Generate a Java code file for the given object model bean, using the
-	 * given template name as the basis for the Java class. 
-	 * 
-	 * @param bean
-	 * @param templateFileName
-	 * @throws IOException
-	 * @throws TemplateException
-	 */
-	public void generateClassFile(BaseBean bean, String templateFileName) 
-		throws IOException, TemplateException
-	{
-		String shortClassName = bean.getClassName().substring(
-			bean.getClassName().lastIndexOf('.') + 1);
-		
-		Map<String, Object> objectMap = new HashMap<String, Object>();
-		objectMap.put("bean", bean);
-		objectMap.put("rootPackageName", this.rootPackageName);
-		objectMap.put("shortClassName", shortClassName);
+   public final static String COMMAND_TEMPLATE_FILENAME = "Command.ftl";
+   public final static String BEAN_TEMPLATE_FILENAME = "Bean.ftl";
 
-		File packageDir = new File(
-			this.targetDirectory, bean.getPackageName().replace('.', '/'));
-		
-		if (packageDir.exists() || packageDir.mkdirs()) {
-			File javaFile = new File(packageDir, shortClassName + ".java");
-			FileWriter fw = new FileWriter(javaFile);
-			System.out.println("Generated " + javaFile);
-			applyTemplate(templateFileName, objectMap, fw);
-		} else {
-			throw new IllegalStateException(
-				"Unable to create target package directory: " + packageDir);
-		}
-	}	
-	
-	/**
-	 * Apply the given template to the given object, and output the results into the given writer.
-	 * 
-	 * @param templateFileName
-	 * @param objectMap
-	 * @param writer
-	 * @throws IOException
-	 * @throws TemplateException
-	 */
-	public void applyTemplate(String templateFileName, Map<String, Object> objectMap, Writer writer) 
-		throws IOException, TemplateException 
-	{
-		Template template = this.config.getTemplate(templateFileName, "UTF-8");
-		template.process(objectMap, writer);		
-	}
+   private final File targetDirectory;
+   private final String rootPackageName;
+   private final Configuration config;
+
+   public CodeGenerator(String rootPackageName, File targetDirectory) throws IOException {
+      this.rootPackageName = rootPackageName;
+      this.targetDirectory = targetDirectory;
+
+      config = new Configuration();
+      config.setClassForTemplateLoading(this.getClass(), "/templates");
+   }
+
+   /**
+    * Parse a JSON object model file (as generated by <tt>aws/src/main/bin/parse_ec2.pl</tt>) and
+    * convert it into a Java object graph.
+    * 
+    * @param objectModelFile
+    * @return
+    * @throws JsonParseException
+    * @throws FileNotFoundException
+    */
+   public Model parseModelFromJSON(File objectModelFile) throws JsonParseException,
+            FileNotFoundException {
+      Gson gson = new Gson();
+      return gson.fromJson(new FileReader(objectModelFile), Model.class);
+   }
+
+   /**
+    * Parse a JSON object model file and iterate over the resulting objects generating Java code
+    * files.
+    * 
+    * @param objectModelFile
+    * @throws JsonParseException
+    * @throws IOException
+    * @throws TemplateException
+    */
+   public void generateCode(File objectModelFile) throws JsonParseException, IOException,
+            TemplateException {
+      Model model = parseModelFromJSON(objectModelFile);
+
+      for (Package pkg : model.getPackages()) {
+         for (Command command : pkg.getCommands()) {
+            generateClassFile(command, COMMAND_TEMPLATE_FILENAME);
+
+            if (command.getHandler() != null) {
+               generateClassFile(command.getHandler(), BEAN_TEMPLATE_FILENAME);
+            }
+            if (command.getOptions() != null) {
+               generateClassFile(command.getOptions(), BEAN_TEMPLATE_FILENAME);
+            }
+            if (command.getResponse() != null) {
+               generateClassFile(command.getResponse(), BEAN_TEMPLATE_FILENAME);
+            }
+         }
+      }
+   }
+
+   /**
+    * Generate a Java code file for the given object model bean, using the given template name as
+    * the basis for the Java class.
+    * 
+    * @param bean
+    * @param templateFileName
+    * @throws IOException
+    * @throws TemplateException
+    */
+   public void generateClassFile(BaseBean bean, String templateFileName) throws IOException,
+            TemplateException {
+      String shortClassName = bean.getClassName().substring(
+               bean.getClassName().lastIndexOf('.') + 1);
+
+      Map<String, Object> objectMap = new HashMap<String, Object>();
+      objectMap.put("bean", bean);
+      objectMap.put("rootPackageName", this.rootPackageName);
+      objectMap.put("shortClassName", shortClassName);
+
+      File packageDir = new File(this.targetDirectory, bean.getPackageName().replace('.', '/'));
+
+      if (packageDir.exists() || packageDir.mkdirs()) {
+         File javaFile = new File(packageDir, shortClassName + ".java");
+         FileWriter fw = new FileWriter(javaFile);
+         System.out.println("Generated " + javaFile);
+         applyTemplate(templateFileName, objectMap, fw);
+      } else {
+         throw new IllegalStateException("Unable to create target package directory: " + packageDir);
+      }
+   }
+
+   /**
+    * Apply the given template to the given object, and output the results into the given writer.
+    * 
+    * @param templateFileName
+    * @param objectMap
+    * @param writer
+    * @throws IOException
+    * @throws TemplateException
+    */
+   public void applyTemplate(String templateFileName, Map<String, Object> objectMap, Writer writer)
+            throws IOException, TemplateException {
+      Template template = this.config.getTemplate(templateFileName, "UTF-8");
+      template.process(objectMap, writer);
+   }
+
+   public static void main(String[] args) throws Exception {
+      if (args.length != 3) {
+         System.out.println("Usage: CodeGenerator objectModelFile rootPackage targetDir");
+         System.out.println("  E.g: CodeGenerator ec2.json org.jclouds.aws.ec2 aws/ec2/api/src");
+         System.exit(1);
+      }
+      File objectModelFile = new File(args[0]);
+
+      String rootPackage = args[1];
+
+      File targetDir = new File(args[2]);
+
+      new CodeGenerator(rootPackage, targetDir).generateCode(objectModelFile);
+   }
 
-	
-	public static void main(String[] args) throws Exception {
-		if (args.length != 4) {
-			System.out.println(
-				"Usage: CodeGenerator objectModelFile rootPackage templatesDir targetDir");
-			System.out.println(
-				"  E.g: CodeGenerator ec2.json org.jclouds.aws.ec2 aws/codegen/templates aws/ec2/api/src");
-			System.exit(1);
-		}
-		
-		CodeGenerator codeGenerator = new CodeGenerator(
-			args[1], new File(args[2]), new File(args[3]));
-		codeGenerator.generateCode(new File(args[0]));
-	}
-	
 }