Refactor: Extract MVEL extension & Improve Code Quality

objectmerger-cli/pom.xml

@@ -16,6 +16,7 @@
     <packaging>jar</packaging>
 
     <dependencies>
+        <!-- Compile dependencies -->
         <dependency>
             <groupId>de.x132</groupId>
             <artifactId>objectmerger</artifactId>
@@ -28,11 +29,15 @@
             <groupId>com.google.code.gson</groupId>
             <artifactId>gson</artifactId>
         </dependency>
+
+        <!-- Provided dependencies -->
         <dependency>
             <groupId>org.projectlombok</groupId>
             <artifactId>lombok</artifactId>
             <scope>provided</scope>
         </dependency>
+
+        <!-- Test dependencies -->
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-api</artifactId>

objectmerger-cli/src/main/java/de/x132/cli/FieldDefinitionDeserializer.java

@@ -13,25 +13,25 @@
 
 public class FieldDefinitionDeserializer implements JsonDeserializer<FieldDefinition<?>> {
 
-  @Override
-  public FieldDefinition<?> deserialize(
-      JsonElement json, Type typeOfT, JsonDeserializationContext context)
-      throws JsonParseException {
+    @Override
+    public FieldDefinition<?> deserialize(
+            JsonElement json, Type typeOfT, JsonDeserializationContext context)
+            throws JsonParseException {
 
-    JsonObject jsonObject = json.getAsJsonObject();
-    String strategyName =
-        jsonObject.has("strategy") ? jsonObject.get("strategy").getAsString() : "standard";
+        JsonObject jsonObject = json.getAsJsonObject();
+        String strategyName =
+                jsonObject.has("strategy") ? jsonObject.get("strategy").getAsString() : "standard";
 
-    MergeStrategy<?, ?> strategy = StrategyRegistry.getInstance().getStrategy(strategyName);
+        MergeStrategy<?, ?> strategy = StrategyRegistry.getInstance().getStrategy(strategyName);
 
-    // The configuration class for the strategy
-    Class<? extends FieldDefinition> configClass = strategy.getConfigurationClass();
+        // The configuration class for the strategy
+        Class<? extends FieldDefinition> configClass = strategy.getConfigurationClass();
 
-    // Prevent infinite recursion if the strategy returns the abstract base class
-    if (configClass == FieldDefinition.class) {
-      configClass = StandardFieldDefinition.class;
-    }
+        // Prevent infinite recursion if the strategy returns the abstract base class
+        if (configClass == FieldDefinition.class) {
+            configClass = StandardFieldDefinition.class;
+        }
 
-    return context.deserialize(json, configClass);
-  }
+        return context.deserialize(json, configClass);
+    }
 }

objectmerger-cli/src/main/java/de/x132/cli/GenerateCommand.java

@@ -17,41 +17,41 @@
 @Command(name = "generate", description = "Generate a merge definition from a sample JSON file")
 public class GenerateCommand implements Callable<Integer> {
 
-  @Parameters(index = "0", description = "Path to sample JSON file")
-  private Path samplePath;
-
-  @Option(
-      names = {"-o", "--output"},
-      description = "Output JSON file; defaults to stdout")
-  private Path outputPath;
-
-  private final Gson gson = new GsonBuilder().setPrettyPrinting().create();
-
-  @Override
-  public Integer call() throws Exception {
-    try {
-      Map<String, Object> sampleData;
-      try (FileReader reader = new FileReader(samplePath.toFile())) {
-        sampleData = gson.fromJson(reader, Map.class);
-      }
-
-      MergeDefinition definition = MergeDefinitionGenerator.generate(sampleData);
-
-      String jsonOut = gson.toJson(definition);
-      if (outputPath != null) {
-        Files.createDirectories(outputPath.toAbsolutePath().getParent());
-        try (FileWriter writer = new FileWriter(outputPath.toFile())) {
-          writer.write(jsonOut);
+    @Parameters(index = "0", description = "Path to sample JSON file")
+    private Path samplePath;
+
+    @Option(
+            names = {"-o", "--output"},
+            description = "Output JSON file; defaults to stdout")
+    private Path outputPath;
+
+    private final Gson gson = new GsonBuilder().setPrettyPrinting().create();
+
+    @Override
+    public Integer call() throws Exception {
+        try {
+            Map<String, Object> sampleData;
+            try (FileReader reader = new FileReader(samplePath.toFile())) {
+                sampleData = gson.fromJson(reader, Map.class);
+            }
+
+            MergeDefinition definition = MergeDefinitionGenerator.generate(sampleData);
+
+            String jsonOut = gson.toJson(definition);
+            if (outputPath != null) {
+                Files.createDirectories(outputPath.toAbsolutePath().getParent());
+                try (FileWriter writer = new FileWriter(outputPath.toFile())) {
+                    writer.write(jsonOut);
+                }
+            } else {
+                System.out.println(jsonOut);
+            }
+            return 0;
+
+        } catch (Exception e) {
+            System.err.println("Generation failed: " + e.getMessage());
+            e.printStackTrace();
+            return 1;
         }
-      } else {
-        System.out.println(jsonOut);
-      }
-      return 0;
-
-    } catch (Exception e) {
-      System.err.println("Generation failed: " + e.getMessage());
-      e.printStackTrace();
-      return 1;
     }
-  }
 }

objectmerger-cli/src/main/java/de/x132/cli/MergeCommand.java

@@ -22,74 +22,75 @@
 @Command(name = "merge", description = "Merge multiple JSON sources")
 public class MergeCommand implements Callable<Integer> {
 
-  @Option(
-      names = {"-d", "--definition"},
-      required = true,
-      description = "Path to merge definition JSON file")
-  private Path definitionPath;
+    @Option(
+            names = {"-d", "--definition"},
+            required = true,
+            description = "Path to merge definition JSON file")
+    private Path definitionPath;
 
-  @Option(
-      names = {"-s", "--source"},
-      required = true,
-      arity = "1..*",
-      description = "Source in format label=path/to.json (repeat for multiple sources)")
-  private List<String> sources;
+    @Option(
+            names = {"-s", "--source"},
+            required = true,
+            arity = "1..*",
+            description = "Source in format label=path/to.json (repeat for multiple sources)")
+    private List<String> sources;
 
-  @Option(
-      names = {"-o", "--output"},
-      description = "Output JSON file; defaults to stdout")
-  private Path outputPath;
+    @Option(
+            names = {"-o", "--output"},
+            description = "Output JSON file; defaults to stdout")
+    private Path outputPath;
 
-  private final Gson gson =
-      new GsonBuilder()
-          .setPrettyPrinting()
-          .registerTypeAdapter(FieldDefinition.class, new FieldDefinitionDeserializer())
-          .create();
+    private final Gson gson =
+            new GsonBuilder()
+                    .setPrettyPrinting()
+                    .registerTypeAdapter(FieldDefinition.class, new FieldDefinitionDeserializer())
+                    .create();
 
-  @Override
-  public Integer call() throws Exception {
-    try {
-      MergeDefinition mergeDefinition;
-      try (FileReader reader = new FileReader(definitionPath.toFile())) {
-        mergeDefinition = gson.fromJson(reader, MergeDefinition.class);
-      }
+    @Override
+    public Integer call() throws Exception {
+        try {
+            MergeDefinition mergeDefinition;
+            try (FileReader reader = new FileReader(definitionPath.toFile())) {
+                mergeDefinition = gson.fromJson(reader, MergeDefinition.class);
+            }
 
-      List<LabeledSource<Map<String, Object>>> labeledSources = new ArrayList<>();
-      for (String src : sources) {
-        int eq = src.indexOf('=');
-        if (eq <= 0 || eq == src.length() - 1) {
-          throw new IllegalArgumentException("Invalid --source format: " + src);
-        }
-        String label = src.substring(0, eq);
-        Path path = Path.of(src.substring(eq + 1));
-        try (FileReader reader = new FileReader(path.toFile())) {
-          Map<String, Object> obj = gson.fromJson(reader, Map.class);
-          labeledSources.add(new LabeledSource<>(label, obj));
-        }
-      }
+            List<LabeledSource<Map<String, Object>>> labeledSources = new ArrayList<>();
+            for (String src : sources) {
+                int eq = src.indexOf('=');
+                if (eq <= 0 || eq == src.length() - 1) {
+                    throw new IllegalArgumentException("Invalid --source format: " + src);
+                }
+                String label = src.substring(0, eq);
+                Path path = Path.of(src.substring(eq + 1));
+                try (FileReader reader = new FileReader(path.toFile())) {
+                    Map<String, Object> obj = gson.fromJson(reader, Map.class);
+                    labeledSources.add(new LabeledSource<>(label, obj));
+                }
+            }
 
-      @SuppressWarnings("unchecked")
-      Map<String, Object> merged =
-          ObjectMerger.merge(mergeDefinition, labeledSources.toArray(LabeledSource[]::new));
+            @SuppressWarnings("unchecked")
+            Map<String, Object> merged =
+                    ObjectMerger.merge(
+                            mergeDefinition, labeledSources.toArray(LabeledSource[]::new));
 
-      String jsonOut = gson.toJson(merged);
-      if (outputPath != null) {
-        Files.createDirectories(outputPath.toAbsolutePath().getParent());
-        try (FileWriter writer = new FileWriter(outputPath.toFile())) {
-          writer.write(jsonOut);
-        }
-      } else {
-        System.out.println(jsonOut);
-      }
-      return 0;
+            String jsonOut = gson.toJson(merged);
+            if (outputPath != null) {
+                Files.createDirectories(outputPath.toAbsolutePath().getParent());
+                try (FileWriter writer = new FileWriter(outputPath.toFile())) {
+                    writer.write(jsonOut);
+                }
+            } else {
+                System.out.println(jsonOut);
+            }
+            return 0;
 
-    } catch (JsonSyntaxException | JsonIOException e) {
-      System.err.println("Failed to parse JSON: " + e.getMessage());
-      return 3;
-    } catch (Exception e) {
-      System.err.println("Merge failed: " + e.getMessage());
-      e.printStackTrace();
-      return 1;
+        } catch (JsonSyntaxException | JsonIOException e) {
+            System.err.println("Failed to parse JSON: " + e.getMessage());
+            return 3;
+        } catch (Exception e) {
+            System.err.println("Merge failed: " + e.getMessage());
+            e.printStackTrace();
+            return 1;
+        }
     }
-  }
 }

objectmerger-cli/src/main/java/de/x132/cli/ObjectMergerCli.java

@@ -4,15 +4,15 @@
 import picocli.CommandLine.Command;
 
 @Command(
-    name = "objectmerger",
-    mixinStandardHelpOptions = true,
-    version = "0.1.0",
-    description = "ObjectMerger CLI tool",
-    subcommands = {MergeCommand.class, GenerateCommand.class})
+        name = "objectmerger",
+        mixinStandardHelpOptions = true,
+        version = "0.1.0",
+        description = "ObjectMerger CLI tool",
+        subcommands = {MergeCommand.class, GenerateCommand.class})
 public class ObjectMergerCli {
 
-  public static void main(String[] args) {
-    int exit = new CommandLine(new ObjectMergerCli()).execute(args);
-    System.exit(exit);
-  }
+    public static void main(String[] args) {
+        int exit = new CommandLine(new ObjectMergerCli()).execute(args);
+        System.exit(exit);
+    }
 }

objectmerger-cli/src/test/java/de/x132/cli/GenerateCommandTest.java

@@ -17,44 +17,47 @@
 
 class GenerateCommandTest {
 
-  private Path tempDir;
-  private Path sampleFile;
-  private Path outputFile;
-
-  @BeforeEach
-  void setUp() throws IOException {
-    tempDir = Files.createTempDirectory("objectmerger-cli-test");
-    sampleFile = tempDir.resolve("sample.json");
-    outputFile = tempDir.resolve("output.json");
-
-    try (FileWriter writer = new FileWriter(sampleFile.toFile())) {
-      writer.write("{\"name\": \"test\", \"value\": 123}");
+    private Path tempDir;
+    private Path sampleFile;
+    private Path outputFile;
+
+    @BeforeEach
+    void setUp() throws IOException {
+        tempDir = Files.createTempDirectory("objectmerger-cli-test");
+        sampleFile = tempDir.resolve("sample.json");
+        outputFile = tempDir.resolve("output.json");
+
+        try (FileWriter writer = new FileWriter(sampleFile.toFile())) {
+            writer.write("{\"name\": \"test\", \"value\": 123}");
+        }
     }
-  }
-
-  @AfterEach
-  void tearDown() throws IOException {
-    Files.walk(tempDir).sorted((a, b) -> b.compareTo(a)).map(Path::toFile).forEach(File::delete);
-  }
-
-  @Test
-  void testGenerate() {
-    GenerateCommand cmd = new GenerateCommand();
-    CommandLine commandLine = new CommandLine(cmd);
-
-    int exitCode = commandLine.execute(sampleFile.toString(), "-o", outputFile.toString());
-
-    assertEquals(0, exitCode);
-    assertTrue(Files.exists(outputFile));
-
-    try {
-      String content = Files.readString(outputFile);
-      Gson gson = new Gson();
-      Map map = gson.fromJson(content, Map.class);
-      assertTrue(((Map) map.get("definitions")).containsKey("name"));
-      assertTrue(((Map) map.get("definitions")).containsKey("value"));
-    } catch (IOException e) {
-      throw new RuntimeException(e);
+
+    @AfterEach
+    void tearDown() throws IOException {
+        Files.walk(tempDir)
+                .sorted((a, b) -> b.compareTo(a))
+                .map(Path::toFile)
+                .forEach(File::delete);
+    }
+
+    @Test
+    void testGenerate() {
+        GenerateCommand cmd = new GenerateCommand();
+        CommandLine commandLine = new CommandLine(cmd);
+
+        int exitCode = commandLine.execute(sampleFile.toString(), "-o", outputFile.toString());
+
+        assertEquals(0, exitCode);
+        assertTrue(Files.exists(outputFile));
+
+        try {
+            String content = Files.readString(outputFile);
+            Gson gson = new Gson();
+            Map map = gson.fromJson(content, Map.class);
+            assertTrue(((Map) map.get("definitions")).containsKey("name"));
+            assertTrue(((Map) map.get("definitions")).containsKey("value"));
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
     }
-  }
 }