Using Pattern Matching for instanceof

cbeust · Dec 23, 2024 · 95acea1 · 95acea1
1 parent 09a6b61
commit 95acea1
Show file tree

Hide file tree

Showing 3 changed files with 16 additions and 19 deletions.
diff --git a/src/main/java/com/beust/jcommander/JCommander.java b/src/main/java/com/beust/jcommander/JCommander.java
@@ -319,9 +319,9 @@ public synchronized Console getConsole() {
      */
     // declared final since this is invoked from constructors
     public final void addObject(Object object) {
-        if (object instanceof Iterable) {
+        if (object instanceof Iterable i) {
             // Iterable
-            for (Object o : (Iterable<?>) object) {
+            for (Object o : i) {
                 objects.add(o);
             }
         } else if (object.getClass().isArray()) {
@@ -835,11 +835,10 @@ else if (commands.isEmpty()) {
                     }
 
                     Type genericType = mainParameter.parameterized.getGenericType();
-                    if (genericType instanceof ParameterizedType) {
-                        ParameterizedType p = (ParameterizedType) genericType;
+                    if (genericType instanceof ParameterizedType p) {
                         Type cls = p.getActualTypeArguments()[0];
-                        if (cls instanceof Class) {
-                            convertedValue = convertValue(mainParameter.parameterized, (Class) cls, null, value);
+                        if (cls instanceof Class c) {
+                            convertedValue = convertValue(mainParameter.parameterized, c, null, value);
                         }
                     }
 
@@ -947,10 +946,10 @@ private int processPassword(String[] args, int index, ParameterDescription pd, b
     private int processVariableArity(String[] args, int index, ParameterDescription pd, boolean validate) {
         Object arg = pd.getObject();
         IVariableArity va;
-        if (!(arg instanceof IVariableArity)) {
+        if (!(arg instanceof IVariableArity iva)) {
             va = DEFAULT_VARIABLE_ARITY;
         } else {
-            va = (IVariableArity) arg;
+            va = iva;
         }
 
         int arity = determineArity(args, index, pd, va);
@@ -1423,7 +1422,7 @@ public Object convertValue(final Parameterized parameterized, Class type, String
                 @Override
                 public Object convert(String value) {
                     final Type genericType = parameterized.findFieldGenericType();
-                    return convertValue(parameterized, genericType instanceof Class ? (Class) genericType : String.class, null, value);
+                    return convertValue(parameterized, genericType instanceof Class c ? c : String.class, null, value);
                 }
             });
         }

diff --git a/src/main/java/com/beust/jcommander/ParameterDescription.java b/src/main/java/com/beust/jcommander/ParameterDescription.java
@@ -263,8 +263,8 @@ Object addValue(String name, String value, boolean isDefault, boolean validate,
           l = newCollection(type);
           parameterized.set(object, l);
       }
-      if (convertedValue instanceof Collection) {
-          l.addAll((Collection) convertedValue);
+      if (convertedValue instanceof Collection c) {
+          l.addAll(c);
       } else {
           l.add(convertedValue);
       }

diff --git a/src/main/java/com/beust/jcommander/Parameterized.java b/src/main/java/com/beust/jcommander/Parameterized.java
@@ -303,8 +303,8 @@ public void set(Object object, Object value) {
       throw new ParameterException(errorMessage(method, ex));
     } catch (InvocationTargetException ex) {
       // If a ParameterException was thrown, don't wrap it into another one
-      if (ex.getTargetException() instanceof ParameterException) {
-        throw (ParameterException) ex.getTargetException();
+      if (ex.getTargetException() instanceof ParameterException pe) {
+        throw pe;
       } else {
         throw new ParameterException(errorMessage(method, ex), ex.getTargetException());
       }
@@ -334,13 +334,11 @@ public Type findFieldGenericType() {
     if (method != null) {
       return null;
     } else {
-      if (field.getGenericType() instanceof ParameterizedType) {
-        ParameterizedType p = (ParameterizedType) field.getGenericType();
+      if (field.getGenericType() instanceof ParameterizedType p) {
         Type cls = p.getActualTypeArguments()[0];
-        if (cls instanceof Class) {
-          return cls;
-        } else if ( cls instanceof WildcardType) {
-          WildcardType wildcardType = (WildcardType)cls;
+        if (cls instanceof Class c) {
+          return c;
+        } else if (cls instanceof WildcardType wildcardType) {
           if (wildcardType.getLowerBounds().length > 0) {
             return wildcardType.getLowerBounds()[0];
           }