fixed error and added @NotNull/@Nullable annotations

angularj-universal-application/src/main/java/ch/swaechter/angularjuniversal/data/DataLoader.java

@@ -1,5 +1,8 @@
 package ch.swaechter.angularjuniversal.data;
 
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
 import java.io.InputStream;
 
 /**
@@ -14,6 +17,7 @@ public class DataLoader {
      *
      * @return Input stream of the index template
      */
+    @Nullable
     public InputStream getIndexAsInputStream() {
         return this.getClass().getResourceAsStream("/public/index.html");
     }
@@ -23,6 +27,7 @@ public InputStream getIndexAsInputStream() {
      *
      * @return Input stream of the server bundle
      */
+    @Nullable
     public InputStream getServerBundleAsInputStream() {
         return this.getClass().getResourceAsStream("/server.js");
     }

angularj-universal-application/src/main/java/ch/swaechter/angularjuniversal/keywords/Keyword.java

@@ -1,5 +1,7 @@
 package ch.swaechter.angularjuniversal.keywords;
 
+import org.jetbrains.annotations.NotNull;
+
 /**
  * This class is responsible for representing a keyword with a name.
  *
@@ -10,17 +12,21 @@ public class Keyword {
     /**
      * ID of the keyword.
      */
+    @NotNull
     private Integer id;
 
     /**
      * Name of the keyword.
      */
+    @NotNull
     private String name;
 
     /**
      * Default constructor.
      */
     public Keyword() {
+        this.id = (int) Math.round(Math.random() * Integer.MAX_VALUE);
+        this.name = "";
     }
 
     /**
@@ -29,7 +35,7 @@ public Keyword() {
      * @param id   ID of the keyword
      * @param name Name of the keyword
      */
-    public Keyword(Integer id, String name) {
+    public Keyword(@NotNull Integer id, @NotNull String name) {
         this.id = id;
         this.name = name;
     }
@@ -39,6 +45,7 @@ public Keyword(Integer id, String name) {
      *
      * @return ID of the keyword
      */
+    @NotNull
     public Integer getId() {
         return id;
     }
@@ -48,8 +55,7 @@ public Integer getId() {
      *
      * @param id New ID of the keyword
      */
-
-    public void setId(Integer id) {
+    public void setId(@NotNull Integer id) {
         this.id = id;
     }
 
@@ -58,6 +64,7 @@ public void setId(Integer id) {
      *
      * @return Name of the keyword
      */
+    @NotNull
     public String getName() {
         return name;
     }
@@ -67,7 +74,7 @@ public String getName() {
      *
      * @param name New name of the keyword
      */
-    public void setName(String name) {
+    public void setName(@NotNull String name) {
         this.name = name;
     }
 }

angularj-universal-application/src/main/java/ch/swaechter/angularjuniversal/keywords/KeywordService.java

@@ -1,5 +1,7 @@
 package ch.swaechter.angularjuniversal.keywords;
 
+import org.jetbrains.annotations.NotNull;
+
 import java.util.Arrays;
 import java.util.List;
 import java.util.Optional;
@@ -11,6 +13,7 @@
  */
 public class KeywordService {
 
+    @NotNull
     private final List<Keyword> keywords;
 
     public KeywordService() {
@@ -25,6 +28,7 @@ public KeywordService() {
      *
      * @return All keywords as list
      */
+    @NotNull
     public List<Keyword> getKeywords() {
         return keywords;
     }
@@ -35,6 +39,7 @@ public List<Keyword> getKeywords() {
      * @param id ID of the keyword
      * @return Optional keyword
      */
+    @NotNull
     public Optional<Keyword> getKeyword(int id) {
         if (id >= 0 && id < keywords.size()) {
             return Optional.of(keywords.get(id));

angularj-universal-example-spring-boot-simple/src/main/java/ch/swaechter/angularjuniversal/example/springboot/simple/WebApplication.java

@@ -7,6 +7,7 @@
 import ch.swaechter.angularjuniversal.renderer.engine.RenderEngineFactory;
 import ch.swaechter.angularjuniversal.renderer.utils.RenderUtils;
 import ch.swaechter.angularjuniversal.tcprenderer.TcpRenderEngineFactory;
+import org.jetbrains.annotations.NotNull;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
@@ -32,33 +33,38 @@ public static void main(String[] args) {
     @RestController
     public class ContentController {
 
+        @NotNull
         private final RenderService renderService;
 
         @Autowired
-        public ContentController(RenderService renderService) {
+        public ContentController(@NotNull RenderService renderService) {
             this.renderService = renderService;
         }
 
         @ResponseBody
         @GetMapping({"/", "/home"})
+        @NotNull
         public String showHome() throws Exception {
             return renderService.renderPage("/home").get();
         }
 
         @ResponseBody
         @GetMapping("/keywords")
+        @NotNull
         public String showLogin() throws Exception {
             return renderService.renderPage("/keywords").get();
         }
 
         @ResponseBody
         @GetMapping("/keywords/{id}")
+        @NotNull
         public String showLogout(@PathVariable("id") int id) throws Exception {
             return renderService.renderPage("/keywords/" + id).get();
         }
 
         @ResponseBody
         @GetMapping("/about")
+        @NotNull
         public String showPage() throws Exception {
             return renderService.renderPage("/about").get();
         }
@@ -68,13 +74,15 @@ public String showPage() throws Exception {
     @RequestMapping("/api")
     public class KeywordController {
 
+        @NotNull
         private final KeywordService keywordService;
 
         public KeywordController() {
             this.keywordService = new KeywordService();
         }
 
         @GetMapping("/keyword")
+        @NotNull
         public ResponseEntity<List<Keyword>> getKeywords() {
             return new ResponseEntity<>(keywordService.getKeywords(), HttpStatus.OK);
         }
@@ -83,8 +91,10 @@ public ResponseEntity<List<Keyword>> getKeywords() {
     @Service
     public class RenderService {
 
+        @NotNull
         private final Renderer renderer;
 
+        @NotNull
         public RenderService() throws IOException {
             // Load the template and create a temporary server bundle file from the resource (This file will of course never change until manually edited)
             InputStream templateInputStream = getClass().getResourceAsStream("/public/index.html");
@@ -105,7 +115,8 @@ public RenderService() throws IOException {
             this.renderer.startRenderer();
         }
 
-        Future<String> renderPage(String uri) {
+        @NotNull
+        Future<String> renderPage(@NotNull String uri) {
             // Render a request and return a resolvable future
             return renderer.addRenderRequest(uri);
         }

angularj-universal-example-spring-boot/src/main/java/ch/swaechter/angularjuniversal/example/springboot/configuration/ApplicationConfiguration.java

@@ -1,5 +1,6 @@
 package ch.swaechter.angularjuniversal.example.springboot.configuration;
 
+import org.jetbrains.annotations.NotNull;
 import org.springframework.stereotype.Component;
 import org.springframework.web.servlet.config.annotation.CorsRegistry;
 import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
@@ -8,7 +9,7 @@
 public class ApplicationConfiguration implements WebMvcConfigurer {
 
     @Override
-    public void addCorsMappings(CorsRegistry corsRegistry) {
+    public void addCorsMappings(@NotNull CorsRegistry corsRegistry) {
         corsRegistry.addMapping("/**").allowedOrigins("http://localhost:4200");
     }
 }

angularj-universal-example-spring-boot/src/main/java/ch/swaechter/angularjuniversal/example/springboot/keywords/KeywordController.java

@@ -2,6 +2,7 @@
 
 import ch.swaechter.angularjuniversal.keywords.Keyword;
 import ch.swaechter.angularjuniversal.keywords.KeywordService;
+import org.jetbrains.annotations.NotNull;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.GetMapping;
@@ -19,6 +20,7 @@
 @RequestMapping("/api")
 public class KeywordController {
 
+    @NotNull
     private final KeywordService keywordService;
 
     /**
@@ -34,6 +36,7 @@ public KeywordController() {
      * @return All keywords
      */
     @GetMapping("/keyword")
+    @NotNull
     public ResponseEntity<List<Keyword>> getKeywords() {
         return new ResponseEntity<>(keywordService.getKeywords(), HttpStatus.OK);
     }

angularj-universal-renderer-tcp/src/main/java/ch/swaechter/angularjuniversal/tcprenderer/TcpRenderEngine.java

@@ -2,8 +2,11 @@
 
 import ch.swaechter.angularjuniversal.renderer.configuration.RenderConfiguration;
 import ch.swaechter.angularjuniversal.renderer.engine.RenderEngine;
+import ch.swaechter.angularjuniversal.renderer.exception.RenderException;
 import ch.swaechter.angularjuniversal.renderer.request.RenderRequest;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.io.BufferedReader;
 import java.io.InputStreamReader;
@@ -23,18 +26,19 @@ public class TcpRenderEngine implements RenderEngine {
     /**
      * Name of the environment variable passed to Node.js to indicate the port.
      */
+    @NotNull
     private static final String NODE_PORT_ENVIRONMENT_VARIABLE_NAME = "NODEPORT";
 
     /**
      * Object mapper used to serialize/deserialize TCP request and responses.
      */
-    private final ObjectMapper objectMapper;
+    @NotNull
+    private final ObjectMapper objectMapper = new ObjectMapper();
 
     /**
      * Create a new TCP based render engine that will access a NodeJS server for rendering
      */
     public TcpRenderEngine() {
-        this.objectMapper = new ObjectMapper();
     }
 
     /**
@@ -45,36 +49,62 @@ public TcpRenderEngine() {
      * @param renderConfiguration Render configuration with the all required information
      */
     @Override
-    public void startWorking(BlockingQueue<Optional<RenderRequest>> renderRequests, RenderConfiguration renderConfiguration) {
+    public void startWorking(@NotNull BlockingQueue<Optional<RenderRequest>> renderRequests, @NotNull RenderConfiguration renderConfiguration) {
         try {
             // Start the Node.js render service
+            @NotNull
             ProcessBuilder processBuilder = new ProcessBuilder(renderConfiguration.getNodePath(), renderConfiguration.getServerBundleFile().getAbsolutePath());
+            @NotNull
             Map<String, String> processEnvironment = processBuilder.environment();
             processEnvironment.put(NODE_PORT_ENVIRONMENT_VARIABLE_NAME, String.valueOf(renderConfiguration.getNodePort()));
+
+            @NotNull
             Process process = processBuilder.start();
 
             while (true) {
                 Optional<RenderRequest> renderRequestItem = renderRequests.take();
+
                 if (renderRequestItem.isPresent()) {
-                    try {
-                        // Get the render request item
-                        RenderRequest renderRequest = renderRequestItem.get();
+                    // Get the render request item
+                    @NotNull
+                    RenderRequest renderRequest = renderRequestItem.get();
 
+                    try {
                         // Create the socket and initialize the writer reader
+                        @NotNull
                         Socket socket = new Socket("localhost", renderConfiguration.getNodePort());
+                        @NotNull
                         PrintWriter writer = new PrintWriter(socket.getOutputStream(), true);
+                        @NotNull
                         BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
 
                         // Write the request
-                        TcpRequest tcpRequest = new TcpRequest(renderRequest.getUuid(), renderRequest.getUri(), renderConfiguration.getTemplateContent());
+                        @NotNull
+                        TcpRequest tcpRequest = new TcpRequest(renderRequest.getId(), renderRequest.getUri(), renderConfiguration.getTemplateContent());
                         writer.println(objectMapper.writeValueAsString(tcpRequest));
                         writer.flush();
 
                         // Read the response
+                        @NotNull
                         TcpResponse tcpResponse = objectMapper.readValue(reader, TcpResponse.class);
-                        renderRequest.getFuture().complete(tcpResponse.getHtml());
-                    } catch (Exception exception) {
+
+                        // Get the error message if an error occurred on the render server
+                        @Nullable
+                        String errorMessage = tcpResponse.getError();
+
+                        // check if an error occurred
+                        if (errorMessage == null) {
+                            renderRequest.getFuture().complete(tcpResponse.getHtml());
+                        } else {
+                            throw new RenderException(errorMessage);
+                        }
+                    } catch (Throwable exception) {
                         exception.printStackTrace();
+                        if (exception instanceof RenderException) {
+                            renderRequest.getFuture().completeExceptionally(exception);
+                        } else {
+                            renderRequest.getFuture().completeExceptionally(new RenderException(exception));
+                        }
                     }
                 } else {
                     process.destroy();

angularj-universal-renderer-tcp/src/main/java/ch/swaechter/angularjuniversal/tcprenderer/TcpRenderEngineFactory.java

@@ -2,6 +2,7 @@
 
 import ch.swaechter.angularjuniversal.renderer.engine.RenderEngine;
 import ch.swaechter.angularjuniversal.renderer.engine.RenderEngineFactory;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Provide a TCP render engine factory which is able to create new TCP render engines.
@@ -16,6 +17,7 @@ public class TcpRenderEngineFactory implements RenderEngineFactory {
      * @return New TCP render engine
      */
     @Override
+    @NotNull
     public RenderEngine createRenderEngine() {
         return new TcpRenderEngine();
     }