tools/build/buck-plugin/src/main/java/org/onosproject/onosjar/SwaggerGenerator.java - onos - Gitiles

 /*
  * 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.onosjar;

 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.google.common.io.ByteStreams;
 import com.google.common.io.Files;
 import com.thoughtworks.qdox.JavaProjectBuilder;
 import com.thoughtworks.qdox.model.DocletTag;
 import com.thoughtworks.qdox.model.JavaAnnotation;
 import com.thoughtworks.qdox.model.JavaClass;
 import com.thoughtworks.qdox.model.JavaMethod;
 import com.thoughtworks.qdox.model.JavaParameter;
 import com.thoughtworks.qdox.model.JavaType;

 import java.io.File;
 import java.io.FileWriter;
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;

 import static com.google.common.base.Strings.isNullOrEmpty;

 /**
  * Generates Swagger JSON artifacts from the Java source files.
  */
 public class SwaggerGenerator {

     private final ObjectMapper mapper = new ObjectMapper();

     private static final String JSON_FILE = "swagger.json";
     private static final String GEN_SRC = "generated-sources";
     private static final String REG_SRC = "/registrator.javat";

     private static final String PATH = "javax.ws.rs.Path";
     private static final String PATH_PARAM = "javax.ws.rs.PathParam";
     private static final String QUERY_PARAM = "javax.ws.rs.QueryParam";
     private static final String POST = "javax.ws.rs.POST";
     private static final String GET = "javax.ws.rs.GET";
     private static final String PUT = "javax.ws.rs.PUT";
     private static final String DELETE = "javax.ws.rs.DELETE";
     private static final String PRODUCES = "javax.ws.rs.Produces";
     private static final String CONSUMES = "javax.ws.rs.Consumes";
     private static final String JSON = "MediaType.APPLICATION_JSON";
     private static final String OCTET_STREAM = "MediaType.APPLICATION_OCTET_STREAM";

     private final List<File> srcs;
     private final List<File> resources;
     private final File srcDirectory;
     private final File resourceDirectory;
     private final File genSrcOutputDirectory;
     private final File genResourcesOutputDirectory;
     private final String webContext;
     private final String apiTitle;
     private final String apiVersion;
     private final String apiPackage;
     private final String apiDescription;

     public SwaggerGenerator(List<File> srcs, List<File> resources,
                             File srcDirectory, File resourceDirectory,
                             File genSrcOutputDirectory, File genResourcesOutputDirectory,
                             String webContext, String apiTitle, String apiVersion,
                             String apiPackage, String apiDescription) {
         this.srcs = srcs;
         this.resources = resources;
         this.srcDirectory = srcDirectory;
         this.resourceDirectory = resourceDirectory;
         this.genSrcOutputDirectory = genSrcOutputDirectory;
         this.genResourcesOutputDirectory = genResourcesOutputDirectory;
         this.webContext = webContext;

         this.apiTitle = apiTitle;
         this.apiVersion = apiVersion;
         this.apiPackage = apiPackage;
         this.apiDescription = apiDescription;
     }

     public void execute() {
         try {
             JavaProjectBuilder builder = new JavaProjectBuilder();
             if (srcDirectory != null) {
                 builder.addSourceTree(new File(srcDirectory, "src/main/java"));
             }
             if (srcs != null) {
                 srcs.forEach(src -> {
                     try {
                         builder.addSource(src);
                     } catch (IOException e) {
                         throw new RuntimeException(e);
                     }
                 });
             }

             ObjectNode root = initializeRoot(webContext, apiTitle, apiVersion, apiDescription);
             ArrayNode tags = mapper.createArrayNode();
             ObjectNode paths = mapper.createObjectNode();
             ObjectNode definitions = mapper.createObjectNode();

             root.set("tags", tags);
             root.set("paths", paths);
             root.set("definitions", definitions);

             // TODO: Process resources to allow lookup of files by name

             builder.getClasses().forEach(jc -> processClass(jc, paths, tags, definitions, srcDirectory));

             if (paths.size() > 0) {
                 genCatalog(genResourcesOutputDirectory, root);
                 if (!isNullOrEmpty(apiPackage)) {
                     genRegistrator(genSrcOutputDirectory, webContext, apiTitle, apiVersion,
                                    apiPackage, apiDescription);
                 }
             }
         } catch (Exception e) {
             e.printStackTrace();
             throw new RuntimeException("Unable to generate ONOS REST API documentation", e);
         }
     }

     // initializes top level root with Swagger required specifications
     private ObjectNode initializeRoot(String webContext, String apiTitle,
                                       String apiVersion, String apiDescription) {
         ObjectNode root = mapper.createObjectNode();
         root.put("swagger", "2.0");
         ObjectNode info = mapper.createObjectNode();
         root.set("info", info);

         root.put("basePath", webContext);
         info.put("version", apiVersion);
         info.put("title", apiTitle);
         info.put("description", apiDescription);

         ArrayNode produces = mapper.createArrayNode();
         produces.add("application/json");
         root.set("produces", produces);

         ArrayNode consumes = mapper.createArrayNode();
         consumes.add("application/json");
         root.set("consumes", consumes);

         return root;
     }

     // Checks whether javaClass has a path tag associated with it and if it does
     // processes its methods and creates a tag for the class on the root
     void processClass(JavaClass javaClass, ObjectNode paths, ArrayNode tags,
                       ObjectNode definitions, File srcDirectory) {
         // If the class does not have a Path tag then ignore it
         JavaAnnotation annotation = getPathAnnotation(javaClass);
         if (annotation == null) {
             return;
         }

         String path = getPath(annotation);
         if (path == null) {
             return;
         }

         String resourcePath = "/" + path;
         String tagPath = path.isEmpty() ? "/" : path;

         // Create tag node for this class.
         ObjectNode tagObject = mapper.createObjectNode();
         tagObject.put("name", tagPath);
         if (javaClass.getComment() != null) {
             tagObject.put("description", shortText(javaClass.getComment()));
         }
         tags.add(tagObject);

         // Create an array node add to all methods from this class.
         ArrayNode tagArray = mapper.createArrayNode();
         tagArray.add(tagPath);

         processAllMethods(javaClass, resourcePath, paths, tagArray, definitions, srcDirectory);
     }

     private JavaAnnotation getPathAnnotation(JavaClass javaClass) {
         Optional<JavaAnnotation> optional = javaClass.getAnnotations()
                 .stream().filter(a -> a.getType().getName().equals(PATH)).findAny();
         return optional.orElse(null);
     }

     // Checks whether a class's methods are REST methods and then places all the
     // methods under a specific path into the paths node
     private void processAllMethods(JavaClass javaClass, String resourcePath,
                                    ObjectNode paths, ArrayNode tagArray, ObjectNode definitions,
                                    File srcDirectory) {
         // map of the path to its methods represented by an ObjectNode
         Map<String, ObjectNode> pathMap = new HashMap<>();

         javaClass.getMethods().forEach(javaMethod -> {
             javaMethod.getAnnotations().forEach(annotation -> {
                 String name = annotation.getType().getName();
                 if (name.equals(POST) || name.equals(GET) || name.equals(DELETE) || name.equals(PUT)) {
                     // substring(12) removes "javax.ws.rs."
                     String method = annotation.getType().toString().substring(12).toLowerCase();
                     processRestMethod(javaMethod, method, pathMap, resourcePath, tagArray, definitions, srcDirectory);
                 }
             });
         });

         // for each path add its methods to the path node
         for (Map.Entry<String, ObjectNode> entry : pathMap.entrySet()) {
             paths.set(entry.getKey(), entry.getValue());
         }


     }

     private void processRestMethod(JavaMethod javaMethod, String method,
                                    Map<String, ObjectNode> pathMap,
                                    String resourcePath, ArrayNode tagArray,
                                    ObjectNode definitions, File srcDirectory) {
         String fullPath = resourcePath, consumes = "", produces = "",
                 comment = javaMethod.getComment();
         DocletTag tag = javaMethod.getTagByName("onos.rsModel");
         for (JavaAnnotation annotation : javaMethod.getAnnotations()) {
             String name = annotation.getType().getName();
             if (name.equals(PATH)) {
                 fullPath = resourcePath + "/" + getPath(annotation);
                 fullPath = fullPath.replaceFirst("^//", "/");
             }
             if (name.equals(CONSUMES)) {
                 consumes = getIOType(annotation);
             }
             if (name.equals(PRODUCES)) {
                 produces = getIOType(annotation);
             }
         }
         ObjectNode methodNode = mapper.createObjectNode();
         methodNode.set("tags", tagArray);

         addSummaryDescriptions(methodNode, comment);
         addJsonSchemaDefinition(srcDirectory, definitions, tag);

         processParameters(javaMethod, methodNode, method, tag);

         processConsumesProduces(methodNode, "consumes", consumes);
         processConsumesProduces(methodNode, "produces", produces);
         if (tag == null || ((method.toLowerCase().equals("post") || method.toLowerCase().equals("put"))
                 && !(tag.getParameters().size() > 1))) {
             addResponses(methodNode, tag, false);
         } else {
             addResponses(methodNode, tag, true);
         }

         ObjectNode operations = pathMap.get(fullPath);
         if (operations == null) {
             operations = mapper.createObjectNode();
             operations.set(method, methodNode);
             pathMap.put(fullPath, operations);
         } else {
             operations.set(method, methodNode);
         }
     }

     private void addJsonSchemaDefinition(File srcDirectory, ObjectNode definitions, DocletTag tag) {
         final File definitionsDirectory;
         if (resourceDirectory != null) {
             definitionsDirectory = new File(resourceDirectory, "definitions");
         } else if (srcDirectory != null) {
             definitionsDirectory = new File(srcDirectory + "/src/main/resources/definitions");
         } else {
             definitionsDirectory = null;
         }
         if (tag != null) {
             tag.getParameters().forEach(param -> {
                 try {
                     File config;
                     if (definitionsDirectory != null) {
                         config = new File(definitionsDirectory.getAbsolutePath() + "/" + param + ".json");
                     } else {
                         config = resources.stream().filter(f -> f.getName().equals(param + ".json")).findFirst().orElse(null);
                     }
                     definitions.set(param, mapper.readTree(config));
                 } catch (IOException e) {
                     throw new RuntimeException(String.format("Could not process %s in %s@%s: %s",
                                                              tag.getName(), tag.getContext(), tag.getLineNumber(),
                                                              e.getMessage()), e);
                 }
             });
         }
     }

     private void processConsumesProduces(ObjectNode methodNode, String type, String io) {
         if (!io.equals("")) {
             ArrayNode array = mapper.createArrayNode();
             methodNode.set(type, array);
             array.add(io);
         }
     }

     private void addSummaryDescriptions(ObjectNode methodNode, String comment) {
         String summary = "", description;
         if (comment != null) {
             if (comment.contains(".")) {
                 int periodIndex = comment.indexOf(".");
                 summary = comment.substring(0, periodIndex);
                 description = comment.length() > periodIndex + 1 ?
                         comment.substring(periodIndex + 1).trim() : "";
             } else {
                 description = comment;
             }
             methodNode.put("summary", summary);
             methodNode.put("description", description);
         }
     }

     // Temporary solution to add responses to a method
     private void addResponses(ObjectNode methodNode, DocletTag tag, boolean responseJson) {
         ObjectNode responses = mapper.createObjectNode();
         methodNode.set("responses", responses);

         ObjectNode success = mapper.createObjectNode();
         success.put("description", "successful operation");
         responses.set("200", success);
         if (tag != null && responseJson) {
             ObjectNode schema = mapper.createObjectNode();
             tag.getParameters().stream().forEach(
                     param -> schema.put("$ref", "#/definitions/" + param));
             success.set("schema", schema);
         }

         ObjectNode defaultObj = mapper.createObjectNode();
         defaultObj.put("description", "Unexpected error");
         responses.set("default", defaultObj);
     }

     // Checks if the annotations has a value of JSON and returns the string
     // that Swagger requires
     private String getIOType(JavaAnnotation annotation) {
         if (annotation.getNamedParameter("value").toString().equals(JSON)) {
             return "application/json";
         } else if (annotation.getNamedParameter("value").toString().equals(OCTET_STREAM)) {
             return "application/octet_stream";
         }
         return "";
     }

     // If the annotation has a Path tag, returns the value with leading and
     // trailing double quotes and slash removed.
     private String getPath(JavaAnnotation annotation) {
         String path = annotation.getNamedParameter("value").toString();
         return path == null ? null : path.replaceAll("(^[\\\"/]*|[/\\\"]*$)", "");
     }

     // Processes parameters of javaMethod and enters the proper key-values into the methodNode
     private void processParameters(JavaMethod javaMethod, ObjectNode methodNode, String method, DocletTag tag) {
         ArrayNode parameters = mapper.createArrayNode();
         methodNode.set("parameters", parameters);
         boolean required = true;

         for (JavaParameter javaParameter : javaMethod.getParameters()) {
             ObjectNode individualParameterNode = mapper.createObjectNode();
             Optional<JavaAnnotation> optional = javaParameter.getAnnotations().stream().filter(
                     annotation -> annotation.getType().getName().equals(PATH_PARAM) ||
                             annotation.getType().getName().equals(QUERY_PARAM)).findAny();
             JavaAnnotation pathType = optional.orElse(null);

             String annotationName = javaParameter.getName();


             if (pathType != null) { //the parameter is a path or query parameter
                 individualParameterNode.put("name",
                                             pathType.getNamedParameter("value")
                                                     .toString().replace("\"", ""));
                 if (pathType.getType().getName().equals(PATH_PARAM)) {
                     individualParameterNode.put("in", "path");
                 } else if (pathType.getType().getName().equals(QUERY_PARAM)) {
                     individualParameterNode.put("in", "query");
                 }
                 individualParameterNode.put("type", getType(javaParameter.getType()));
             } else { // the parameter is a body parameter
                 individualParameterNode.put("name", annotationName);
                 individualParameterNode.put("in", "body");

                 // Adds the reference to the Json model for the input
                 // that goes in the post or put operation
                 if (tag != null && (method.toLowerCase().equals("post") ||
                         method.toLowerCase().equals("put"))) {
                     ObjectNode schema = mapper.createObjectNode();
                     tag.getParameters().stream().forEach(param -> {
                         schema.put("$ref", "#/definitions/" + param);
                     });
                     individualParameterNode.set("schema", schema);
                 }
             }
             for (DocletTag p : javaMethod.getTagsByName("param")) {
                 if (p.getValue().contains(annotationName)) {
                     String description = "";
                     if (p.getValue().split(" ", 2).length >= 2) {
                         description = p.getValue().split(" ", 2)[1].trim();
                         if (description.contains("optional")) {
                             required = false;
                         }
                     } else {
                         throw new RuntimeException(String.format("No description for parameter \"%s\" in " +
                                                                          "method \"%s\" in %s (line %d)",
                                                                  p.getValue(), javaMethod.getName(),
                                                                  javaMethod.getDeclaringClass().getName(),
                                                                  javaMethod.getLineNumber()));
                     }
                     individualParameterNode.put("description", description);
                 }
             }
             individualParameterNode.put("required", required);
             parameters.add(individualParameterNode);
         }
     }

     // Returns the Swagger specified strings for the type of a parameter
     private String getType(JavaType javaType) {
         String type = javaType.getFullyQualifiedName();
         String value;
         if (type.equals(String.class.getName())) {
             value = "string";
         } else if (type.equals("int")) {
             value = "integer";
         } else if (type.equals(boolean.class.getName())) {
             value = "boolean";
         } else if (type.equals(long.class.getName())) {
             value = "number";
         } else {
             value = "";
         }
         return value;
     }

     // Writes the swagger.json file using the supplied JSON root.
     private void genCatalog(File dstDirectory, ObjectNode root) {
         File swaggerCfg = new File(dstDirectory, JSON_FILE);
         if (dstDirectory.exists() || dstDirectory.mkdirs()) {
             try (FileWriter fw = new FileWriter(swaggerCfg);
                  PrintWriter pw = new PrintWriter(fw)) {
                 pw.println(root.toString());
             } catch (IOException e) {
                 throw new RuntimeException("Unable to write " + JSON_FILE, e);
             }
         } else {
             throw new RuntimeException("Unable to create " + dstDirectory);
         }
     }

     // Generates the registrator Java component.
     private void genRegistrator(File dstDirectory, String webContext,
                                 String apiTitle, String apiVersion,
                                 String apiPackage, String apiDescription) {
         File dir = new File(dstDirectory, resourceDirectory != null ? GEN_SRC : ".");
         File reg = new File(dir, apiRegistratorPath(apiPackage));
         File pkg = reg.getParentFile();
         if (pkg.exists() || pkg.mkdirs()) {
             try {
                 String src = new String(ByteStreams.toByteArray(getClass().getResourceAsStream(REG_SRC)));
                 src = src.replace("${api.package}", apiPackage)
                         .replace("${web.context}", webContext)
                         .replace("${api.title}", apiTitle)
                         .replace("${api.description}", apiDescription);
                 Files.write(src.getBytes(), reg);
             } catch (IOException e) {
                 throw new RuntimeException("Unable to write " + reg, e);
             }
         } else {
             throw new RuntimeException("Unable to create " + reg);
         }
     }

     private String shortText(String comment) {
         int i = comment.indexOf('.');
         return i > 0 ? comment.substring(0, i) : comment;
     }

     public static String apiRegistratorPath(String apiPackage) {
         return apiPackage.replaceAll("\\.", "/") + "/ApiDocRegistrator.java";
     }
 }
	/*
	* 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.onosjar;

	import com.fasterxml.jackson.databind.ObjectMapper;
	import com.fasterxml.jackson.databind.node.ArrayNode;
	import com.fasterxml.jackson.databind.node.ObjectNode;
	import com.google.common.io.ByteStreams;
	import com.google.common.io.Files;
	import com.thoughtworks.qdox.JavaProjectBuilder;
	import com.thoughtworks.qdox.model.DocletTag;
	import com.thoughtworks.qdox.model.JavaAnnotation;
	import com.thoughtworks.qdox.model.JavaClass;
	import com.thoughtworks.qdox.model.JavaMethod;
	import com.thoughtworks.qdox.model.JavaParameter;
	import com.thoughtworks.qdox.model.JavaType;

	import java.io.File;
	import java.io.FileWriter;
	import java.io.IOException;
	import java.io.PrintWriter;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Map;
	import java.util.Optional;

	import static com.google.common.base.Strings.isNullOrEmpty;

	/**
	* Generates Swagger JSON artifacts from the Java source files.
	*/
	public class SwaggerGenerator {

	private final ObjectMapper mapper = new ObjectMapper();

	private static final String JSON_FILE = "swagger.json";
	private static final String GEN_SRC = "generated-sources";
	private static final String REG_SRC = "/registrator.javat";

	private static final String PATH = "javax.ws.rs.Path";
	private static final String PATH_PARAM = "javax.ws.rs.PathParam";
	private static final String QUERY_PARAM = "javax.ws.rs.QueryParam";
	private static final String POST = "javax.ws.rs.POST";
	private static final String GET = "javax.ws.rs.GET";
	private static final String PUT = "javax.ws.rs.PUT";
	private static final String DELETE = "javax.ws.rs.DELETE";
	private static final String PRODUCES = "javax.ws.rs.Produces";
	private static final String CONSUMES = "javax.ws.rs.Consumes";
	private static final String JSON = "MediaType.APPLICATION_JSON";
	private static final String OCTET_STREAM = "MediaType.APPLICATION_OCTET_STREAM";

	private final List<File> srcs;
	private final List<File> resources;
	private final File srcDirectory;
	private final File resourceDirectory;
	private final File genSrcOutputDirectory;
	private final File genResourcesOutputDirectory;
	private final String webContext;
	private final String apiTitle;
	private final String apiVersion;
	private final String apiPackage;
	private final String apiDescription;

	public SwaggerGenerator(List<File> srcs, List<File> resources,
	File srcDirectory, File resourceDirectory,
	File genSrcOutputDirectory, File genResourcesOutputDirectory,
	String webContext, String apiTitle, String apiVersion,
	String apiPackage, String apiDescription) {
	this.srcs = srcs;
	this.resources = resources;
	this.srcDirectory = srcDirectory;
	this.resourceDirectory = resourceDirectory;
	this.genSrcOutputDirectory = genSrcOutputDirectory;
	this.genResourcesOutputDirectory = genResourcesOutputDirectory;
	this.webContext = webContext;

	this.apiTitle = apiTitle;
	this.apiVersion = apiVersion;
	this.apiPackage = apiPackage;
	this.apiDescription = apiDescription;
	}

	public void execute() {
	try {
	JavaProjectBuilder builder = new JavaProjectBuilder();
	if (srcDirectory != null) {
	builder.addSourceTree(new File(srcDirectory, "src/main/java"));
	}
	if (srcs != null) {
	srcs.forEach(src -> {
	try {
	builder.addSource(src);
	} catch (IOException e) {
	throw new RuntimeException(e);
	}
	});
	}

	ObjectNode root = initializeRoot(webContext, apiTitle, apiVersion, apiDescription);
	ArrayNode tags = mapper.createArrayNode();
	ObjectNode paths = mapper.createObjectNode();
	ObjectNode definitions = mapper.createObjectNode();

	root.set("tags", tags);
	root.set("paths", paths);
	root.set("definitions", definitions);

	// TODO: Process resources to allow lookup of files by name

	builder.getClasses().forEach(jc -> processClass(jc, paths, tags, definitions, srcDirectory));

	if (paths.size() > 0) {
	genCatalog(genResourcesOutputDirectory, root);
	if (!isNullOrEmpty(apiPackage)) {
	genRegistrator(genSrcOutputDirectory, webContext, apiTitle, apiVersion,
	apiPackage, apiDescription);
	}
	}
	} catch (Exception e) {
	e.printStackTrace();
	throw new RuntimeException("Unable to generate ONOS REST API documentation", e);
	}
	}

	// initializes top level root with Swagger required specifications
	private ObjectNode initializeRoot(String webContext, String apiTitle,
	String apiVersion, String apiDescription) {
	ObjectNode root = mapper.createObjectNode();
	root.put("swagger", "2.0");
	ObjectNode info = mapper.createObjectNode();
	root.set("info", info);

	root.put("basePath", webContext);
	info.put("version", apiVersion);
	info.put("title", apiTitle);
	info.put("description", apiDescription);

	ArrayNode produces = mapper.createArrayNode();
	produces.add("application/json");
	root.set("produces", produces);

	ArrayNode consumes = mapper.createArrayNode();
	consumes.add("application/json");
	root.set("consumes", consumes);

	return root;
	}

	// Checks whether javaClass has a path tag associated with it and if it does
	// processes its methods and creates a tag for the class on the root
	void processClass(JavaClass javaClass, ObjectNode paths, ArrayNode tags,
	ObjectNode definitions, File srcDirectory) {
	// If the class does not have a Path tag then ignore it
	JavaAnnotation annotation = getPathAnnotation(javaClass);
	if (annotation == null) {
	return;
	}

	String path = getPath(annotation);
	if (path == null) {
	return;
	}

	String resourcePath = "/" + path;
	String tagPath = path.isEmpty() ? "/" : path;

	// Create tag node for this class.
	ObjectNode tagObject = mapper.createObjectNode();
	tagObject.put("name", tagPath);
	if (javaClass.getComment() != null) {
	tagObject.put("description", shortText(javaClass.getComment()));
	}
	tags.add(tagObject);

	// Create an array node add to all methods from this class.
	ArrayNode tagArray = mapper.createArrayNode();
	tagArray.add(tagPath);

	processAllMethods(javaClass, resourcePath, paths, tagArray, definitions, srcDirectory);
	}

	private JavaAnnotation getPathAnnotation(JavaClass javaClass) {
	Optional<JavaAnnotation> optional = javaClass.getAnnotations()
	.stream().filter(a -> a.getType().getName().equals(PATH)).findAny();
	return optional.orElse(null);
	}

	// Checks whether a class's methods are REST methods and then places all the
	// methods under a specific path into the paths node
	private void processAllMethods(JavaClass javaClass, String resourcePath,
	ObjectNode paths, ArrayNode tagArray, ObjectNode definitions,
	File srcDirectory) {
	// map of the path to its methods represented by an ObjectNode
	Map<String, ObjectNode> pathMap = new HashMap<>();

	javaClass.getMethods().forEach(javaMethod -> {
	javaMethod.getAnnotations().forEach(annotation -> {
	String name = annotation.getType().getName();
	if (name.equals(POST) \|\| name.equals(GET) \|\| name.equals(DELETE) \|\| name.equals(PUT)) {
	// substring(12) removes "javax.ws.rs."
	String method = annotation.getType().toString().substring(12).toLowerCase();
	processRestMethod(javaMethod, method, pathMap, resourcePath, tagArray, definitions, srcDirectory);
	}
	});
	});

	// for each path add its methods to the path node
	for (Map.Entry<String, ObjectNode> entry : pathMap.entrySet()) {
	paths.set(entry.getKey(), entry.getValue());
	}


	}

	private void processRestMethod(JavaMethod javaMethod, String method,
	Map<String, ObjectNode> pathMap,
	String resourcePath, ArrayNode tagArray,
	ObjectNode definitions, File srcDirectory) {
	String fullPath = resourcePath, consumes = "", produces = "",
	comment = javaMethod.getComment();
	DocletTag tag = javaMethod.getTagByName("onos.rsModel");
	for (JavaAnnotation annotation : javaMethod.getAnnotations()) {
	String name = annotation.getType().getName();
	if (name.equals(PATH)) {
	fullPath = resourcePath + "/" + getPath(annotation);
	fullPath = fullPath.replaceFirst("^//", "/");
	}
	if (name.equals(CONSUMES)) {
	consumes = getIOType(annotation);
	}
	if (name.equals(PRODUCES)) {
	produces = getIOType(annotation);
	}
	}
	ObjectNode methodNode = mapper.createObjectNode();
	methodNode.set("tags", tagArray);

	addSummaryDescriptions(methodNode, comment);
	addJsonSchemaDefinition(srcDirectory, definitions, tag);

	processParameters(javaMethod, methodNode, method, tag);

	processConsumesProduces(methodNode, "consumes", consumes);
	processConsumesProduces(methodNode, "produces", produces);
	if (tag == null \|\| ((method.toLowerCase().equals("post") \|\| method.toLowerCase().equals("put"))
	&& !(tag.getParameters().size() > 1))) {
	addResponses(methodNode, tag, false);
	} else {
	addResponses(methodNode, tag, true);
	}

	ObjectNode operations = pathMap.get(fullPath);
	if (operations == null) {
	operations = mapper.createObjectNode();
	operations.set(method, methodNode);
	pathMap.put(fullPath, operations);
	} else {
	operations.set(method, methodNode);
	}
	}

	private void addJsonSchemaDefinition(File srcDirectory, ObjectNode definitions, DocletTag tag) {
	final File definitionsDirectory;
	if (resourceDirectory != null) {
	definitionsDirectory = new File(resourceDirectory, "definitions");
	} else if (srcDirectory != null) {
	definitionsDirectory = new File(srcDirectory + "/src/main/resources/definitions");
	} else {
	definitionsDirectory = null;
	}
	if (tag != null) {
	tag.getParameters().forEach(param -> {
	try {
	File config;
	if (definitionsDirectory != null) {
	config = new File(definitionsDirectory.getAbsolutePath() + "/" + param + ".json");
	} else {
	config = resources.stream().filter(f -> f.getName().equals(param + ".json")).findFirst().orElse(null);
	}
	definitions.set(param, mapper.readTree(config));
	} catch (IOException e) {
	throw new RuntimeException(String.format("Could not process %s in %s@%s: %s",
	tag.getName(), tag.getContext(), tag.getLineNumber(),
	e.getMessage()), e);
	}
	});
	}
	}

	private void processConsumesProduces(ObjectNode methodNode, String type, String io) {
	if (!io.equals("")) {
	ArrayNode array = mapper.createArrayNode();
	methodNode.set(type, array);
	array.add(io);
	}
	}

	private void addSummaryDescriptions(ObjectNode methodNode, String comment) {
	String summary = "", description;
	if (comment != null) {
	if (comment.contains(".")) {
	int periodIndex = comment.indexOf(".");
	summary = comment.substring(0, periodIndex);
	description = comment.length() > periodIndex + 1 ?
	comment.substring(periodIndex + 1).trim() : "";
	} else {
	description = comment;
	}
	methodNode.put("summary", summary);
	methodNode.put("description", description);
	}
	}

	// Temporary solution to add responses to a method
	private void addResponses(ObjectNode methodNode, DocletTag tag, boolean responseJson) {
	ObjectNode responses = mapper.createObjectNode();
	methodNode.set("responses", responses);

	ObjectNode success = mapper.createObjectNode();
	success.put("description", "successful operation");
	responses.set("200", success);
	if (tag != null && responseJson) {
	ObjectNode schema = mapper.createObjectNode();
	tag.getParameters().stream().forEach(
	param -> schema.put("$ref", "#/definitions/" + param));
	success.set("schema", schema);
	}

	ObjectNode defaultObj = mapper.createObjectNode();
	defaultObj.put("description", "Unexpected error");
	responses.set("default", defaultObj);
	}

	// Checks if the annotations has a value of JSON and returns the string
	// that Swagger requires
	private String getIOType(JavaAnnotation annotation) {
	if (annotation.getNamedParameter("value").toString().equals(JSON)) {
	return "application/json";
	} else if (annotation.getNamedParameter("value").toString().equals(OCTET_STREAM)) {
	return "application/octet_stream";
	}
	return "";
	}

	// If the annotation has a Path tag, returns the value with leading and
	// trailing double quotes and slash removed.
	private String getPath(JavaAnnotation annotation) {
	String path = annotation.getNamedParameter("value").toString();
	return path == null ? null : path.replaceAll("(^[\\\"/]\|[/\\\"]$)", "");
	}

	// Processes parameters of javaMethod and enters the proper key-values into the methodNode
	private void processParameters(JavaMethod javaMethod, ObjectNode methodNode, String method, DocletTag tag) {
	ArrayNode parameters = mapper.createArrayNode();
	methodNode.set("parameters", parameters);
	boolean required = true;

	for (JavaParameter javaParameter : javaMethod.getParameters()) {
	ObjectNode individualParameterNode = mapper.createObjectNode();
	Optional<JavaAnnotation> optional = javaParameter.getAnnotations().stream().filter(
	annotation -> annotation.getType().getName().equals(PATH_PARAM) \|\|
	annotation.getType().getName().equals(QUERY_PARAM)).findAny();
	JavaAnnotation pathType = optional.orElse(null);

	String annotationName = javaParameter.getName();


	if (pathType != null) { //the parameter is a path or query parameter
	individualParameterNode.put("name",
	pathType.getNamedParameter("value")
	.toString().replace("\"", ""));
	if (pathType.getType().getName().equals(PATH_PARAM)) {
	individualParameterNode.put("in", "path");
	} else if (pathType.getType().getName().equals(QUERY_PARAM)) {
	individualParameterNode.put("in", "query");
	}
	individualParameterNode.put("type", getType(javaParameter.getType()));
	} else { // the parameter is a body parameter
	individualParameterNode.put("name", annotationName);
	individualParameterNode.put("in", "body");

	// Adds the reference to the Json model for the input
	// that goes in the post or put operation
	if (tag != null && (method.toLowerCase().equals("post") \|\|
	method.toLowerCase().equals("put"))) {
	ObjectNode schema = mapper.createObjectNode();
	tag.getParameters().stream().forEach(param -> {
	schema.put("$ref", "#/definitions/" + param);
	});
	individualParameterNode.set("schema", schema);
	}
	}
	for (DocletTag p : javaMethod.getTagsByName("param")) {
	if (p.getValue().contains(annotationName)) {
	String description = "";
	if (p.getValue().split(" ", 2).length >= 2) {
	description = p.getValue().split(" ", 2)[1].trim();
	if (description.contains("optional")) {
	required = false;
	}
	} else {
	throw new RuntimeException(String.format("No description for parameter \"%s\" in " +
	"method \"%s\" in %s (line %d)",
	p.getValue(), javaMethod.getName(),
	javaMethod.getDeclaringClass().getName(),
	javaMethod.getLineNumber()));
	}
	individualParameterNode.put("description", description);
	}
	}
	individualParameterNode.put("required", required);
	parameters.add(individualParameterNode);
	}
	}

	// Returns the Swagger specified strings for the type of a parameter
	private String getType(JavaType javaType) {
	String type = javaType.getFullyQualifiedName();
	String value;
	if (type.equals(String.class.getName())) {
	value = "string";
	} else if (type.equals("int")) {
	value = "integer";
	} else if (type.equals(boolean.class.getName())) {
	value = "boolean";
	} else if (type.equals(long.class.getName())) {
	value = "number";
	} else {
	value = "";
	}
	return value;
	}

	// Writes the swagger.json file using the supplied JSON root.
	private void genCatalog(File dstDirectory, ObjectNode root) {
	File swaggerCfg = new File(dstDirectory, JSON_FILE);
	if (dstDirectory.exists() \|\| dstDirectory.mkdirs()) {
	try (FileWriter fw = new FileWriter(swaggerCfg);
	PrintWriter pw = new PrintWriter(fw)) {
	pw.println(root.toString());
	} catch (IOException e) {
	throw new RuntimeException("Unable to write " + JSON_FILE, e);
	}
	} else {
	throw new RuntimeException("Unable to create " + dstDirectory);
	}
	}

	// Generates the registrator Java component.
	private void genRegistrator(File dstDirectory, String webContext,
	String apiTitle, String apiVersion,
	String apiPackage, String apiDescription) {
	File dir = new File(dstDirectory, resourceDirectory != null ? GEN_SRC : ".");
	File reg = new File(dir, apiRegistratorPath(apiPackage));
	File pkg = reg.getParentFile();
	if (pkg.exists() \|\| pkg.mkdirs()) {
	try {
	String src = new String(ByteStreams.toByteArray(getClass().getResourceAsStream(REG_SRC)));
	src = src.replace("${api.package}", apiPackage)
	.replace("${web.context}", webContext)
	.replace("${api.title}", apiTitle)
	.replace("${api.description}", apiDescription);
	Files.write(src.getBytes(), reg);
	} catch (IOException e) {
	throw new RuntimeException("Unable to write " + reg, e);
	}
	} else {
	throw new RuntimeException("Unable to create " + reg);
	}
	}

	private String shortText(String comment) {
	int i = comment.indexOf('.');
	return i > 0 ? comment.substring(0, i) : comment;
	}

	public static String apiRegistratorPath(String apiPackage) {
	return apiPackage.replaceAll("\\.", "/") + "/ApiDocRegistrator.java";
	}
	}