Started migration to JDK 21 (unfinished)

pom.xml

@@ -54,8 +54,8 @@
     </organization>
 
     <properties>
-        <java.version>20</java.version>
-        <maven.compiler.release>20</maven.compiler.release>
+        <java.version>21</java.version>
+        <maven.compiler.release>21</maven.compiler.release>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <maven-surefire-plugin.version>3.1.2</maven-surefire-plugin.version>

src/main/java/com/itemis/fluffyj/memory/FluffyMemory.java

@@ -5,6 +5,7 @@
 import com.itemis.fluffyj.exceptions.InstantiationNotPermittedException;
 import com.itemis.fluffyj.memory.api.FluffySegment;
 
+import java.lang.foreign.Arena;
 import java.lang.foreign.MemorySegment;
 
 /**
@@ -36,7 +37,7 @@ public static FluffyMemoryPointerBuilder pointer() {
      *
      * @param nativeSeg - The raw {@link MemorySegment} to wrap.
      */
-    public static FluffyMemorySegmentWrapper wrap(MemorySegment nativeSeg) {
+    public static FluffyMemorySegmentWrapper wrap(final MemorySegment nativeSeg) {
         requireNonNull(nativeSeg, "nativeSeg");
         return new FluffyMemorySegmentWrapper(nativeSeg);
     }
@@ -47,8 +48,8 @@ public static FluffyMemorySegmentWrapper wrap(MemorySegment nativeSeg) {
      * @param nativePtr - Dereference the address found inside this ptr segment.
      * @return - Entry point for easy dereferenciation.
      */
-    public static FluffyMemoryDereferencer dereference(MemorySegment nativePtr) {
-        return new FluffyMemoryDereferencer(wrap(nativePtr), nativePtr);
+    public static FluffyMemoryDereferencer dereference(final MemorySegment nativePtr) {
+        return new FluffyMemoryDereferencer(wrap(nativePtr), Arena.ofAuto());
     }
 
     /**
@@ -57,8 +58,8 @@ public static FluffyMemoryDereferencer dereference(MemorySegment nativePtr) {
      * @param address - Dereference this address.
      * @return - Entry point for easy dereferenciation.
      */
-    public static FluffyMemoryDereferencer dereference(long address) {
-        var nativeSeg = MemorySegment.ofAddress(address);
+    public static FluffyMemoryDereferencer dereference(final long address) {
+        final var nativeSeg = MemorySegment.ofAddress(address);
         return dereference(nativeSeg);
     }
 

src/main/java/com/itemis/fluffyj/memory/FluffyMemoryDereferencer.java

@@ -2,15 +2,15 @@
 
 import static java.util.Objects.requireNonNull;
 
-import java.lang.foreign.MemorySegment;
+import java.lang.foreign.Arena;
 
 /**
  * Provides shortcuts for dereferencing pointers.
  */
 public final class FluffyMemoryDereferencer {
 
-    private FluffyMemorySegmentWrapper wrapper;
-    private MemorySegment nativePtr;
+    private final FluffyMemorySegmentWrapper wrapper;
+    private final Arena arena;
 
     /**
      * Construct a new instance.
@@ -19,9 +19,9 @@ public final class FluffyMemoryDereferencer {
      *        {@link FluffyMemory#wrap(java.lang.foreign.MemorySegment)}.
      * @param nativePtr - The segment that was wrapped with the {@code wrapper}.
      */
-    FluffyMemoryDereferencer(FluffyMemorySegmentWrapper wrapper, MemorySegment nativePtr) {
+    FluffyMemoryDereferencer(final FluffyMemorySegmentWrapper wrapper, final Arena arena) {
         this.wrapper = requireNonNull(wrapper, "wrapper");
-        this.nativePtr = requireNonNull(nativePtr, "nativePtr");
+        this.arena = requireNonNull(arena, "arena");
     }
 
     /**
@@ -31,7 +31,7 @@ public final class FluffyMemoryDereferencer {
      * @param targetType - An instance of this class will be returned.
      * @return An instance of T that was read from an address of off heap memory.
      */
-    public <T> T as(Class<? extends T> targetType) {
-        return wrapper.asPointerOf(targetType).allocate(nativePtr.scope()).dereference();
+    public <T> T as(final Class<? extends T> targetType) {
+        return wrapper.asPointerOf(targetType).allocate(arena).dereference();
     }
 }

src/main/java/com/itemis/fluffyj/memory/FluffyMemoryFuncPointerBuilder.java

@@ -1,7 +1,6 @@
 package com.itemis.fluffyj.memory;
 
 import static java.lang.foreign.Linker.nativeLinker;
-import static java.lang.foreign.SegmentScope.global;
 import static java.lang.invoke.MethodHandles.lookup;
 import static java.lang.invoke.MethodType.methodType;
 import static java.util.Arrays.stream;
@@ -17,10 +16,10 @@
 import com.itemis.fluffyj.memory.internal.FluffyMemoryFuncPointerBuilderStages.ReturnTypeStage;
 import com.itemis.fluffyj.memory.internal.FluffyMemoryFuncPointerBuilderStages.TypeConverterStage;
 
+import java.lang.foreign.Arena;
 import java.lang.foreign.FunctionDescriptor;
 import java.lang.foreign.MemoryLayout;
 import java.lang.foreign.MemorySegment;
-import java.lang.foreign.SegmentScope;
 import java.lang.invoke.MethodHandle;
 import java.lang.reflect.Method;
 import java.util.List;
@@ -50,7 +49,7 @@ public final class FluffyMemoryFuncPointerBuilder
      * @param conv - A {@link FluffyMemoryTypeConverter} that will be used to convert between JVM
      *        and native type arguments and return types.
      */
-    public FluffyMemoryFuncPointerBuilder(String funcName, FluffyMemoryTypeConverter conv) {
+    public FluffyMemoryFuncPointerBuilder(final String funcName, final FluffyMemoryTypeConverter conv) {
         this.funcName = requireNonNull(funcName, "funcName");
         this.typeConverter = requireNonNull(conv, "conv");
     }
@@ -61,30 +60,30 @@ public FluffyMemoryFuncPointerBuilder(String funcName, FluffyMemoryTypeConverter
      *
      * @param funcName - Name of the JVM method to point to.
      */
-    public FluffyMemoryFuncPointerBuilder(String funcName) {
+    public FluffyMemoryFuncPointerBuilder(final String funcName) {
         this.funcName = requireNonNull(funcName, "funcName");
     }
 
     @Override
-    public ArgsStage of(Object receiver) {
+    public ArgsStage of(final Object receiver) {
         this.receiver = requireNonNull(receiver, "receiver");
         return this;
     }
 
     @Override
-    public TypeConverterStage ofType(Object receiver) {
+    public TypeConverterStage ofType(final Object receiver) {
         this.receiver = requireNonNull(receiver, "receiver");
         return this;
     }
 
     @Override
-    public ArgsStage withTypeConverter(FluffyMemoryTypeConverter conv) {
+    public ArgsStage withTypeConverter(final FluffyMemoryTypeConverter conv) {
         this.typeConverter = requireNonNull(conv, "conv");
         return this;
     }
 
     @Override
-    public ReturnTypeStage withArgs(MemoryLayout... args) {
+    public ReturnTypeStage withArgs(final MemoryLayout... args) {
         nativeArgTypes = requireNonNull(args, "args");
         javaArgTypes = typeConverter.getJvmTypes(args);
         return this;
@@ -97,14 +96,14 @@ public ReturnTypeStage withoutArgs() {
 
     @Override
     public MemorySegment autoBind() {
-        return autoBindTo(global());
+        return autoBindTo(Arena.global());
     }
 
     @Override
-    public MemorySegment autoBindTo(SegmentScope scope) {
-        requireNonNull(scope, "scope");
+    public MemorySegment autoBindTo(final Arena arena) {
+        requireNonNull(arena, "arena");
 
-        var candidateMethods = extractMethodCandidates();
+        final var candidateMethods = extractMethodCandidates();
 
         if (candidateMethods.isEmpty()) {
             throwCannotFindMethod(null);
@@ -114,7 +113,7 @@ public MemorySegment autoBindTo(SegmentScope scope) {
             throw new FluffyMemoryException(
                 "Cannot autobind overloaded method '" + funcName + "'. Please perform manual bind.");
         }
-        var method = candidateMethods.get(0);
+        final var method = candidateMethods.get(0);
 
         if (!method.canAccess(receiver)) {
             throwCannotBindNonAccessibleMethod();
@@ -123,7 +122,7 @@ public MemorySegment autoBindTo(SegmentScope scope) {
         javaArgTypes = method.getParameterTypes();
         try {
             nativeArgTypes = typeConverter.getNativeTypes(javaArgTypes);
-        } catch (FluffyMemoryException e) {
+        } catch (final FluffyMemoryException e) {
             throw new FluffyMemoryException(
                 "Method '" + funcName + "' of type " + receiver.getClass().getCanonicalName()
                     + " has unsupported argument types.",
@@ -133,21 +132,22 @@ public MemorySegment autoBindTo(SegmentScope scope) {
         if (javaReturnType.equals(Void.class)) {
             throw new FluffyMemoryException("Return type " + Void.class.getCanonicalName() + " is unsupported. Use "
                 + void.class.getCanonicalName());
-        } else if (!(javaReturnType.equals(void.class))) {
+        }
+        if (!(javaReturnType.equals(void.class))) {
             try {
                 nativeReturnType = Optional.of(typeConverter.getNativeType(javaReturnType));
-            } catch (FluffyMemoryException e) {
+            } catch (final FluffyMemoryException e) {
                 throw new FluffyMemoryException(
                     "Method '" + funcName + "' of type " + receiver.getClass().getCanonicalName()
                         + " has unsupported return type.",
                     e);
             }
         }
-        return bindTo(scope);
+        return bindTo(arena);
     }
 
     @Override
-    public BinderStage andReturnType(MemoryLayout returnType) {
+    public BinderStage andReturnType(final MemoryLayout returnType) {
         requireNonNull(returnType, "returnType");
 
         nativeReturnType = Optional.of(returnType);
@@ -162,8 +162,8 @@ public BinderStage andNoReturnType() {
     }
 
     @Override
-    public MemorySegment bindTo(SegmentScope scope) {
-        requireNonNull(scope, "scope");
+    public MemorySegment bindTo(final Arena arena) {
+        requireNonNull(arena, "scope");
 
         if (extractMethodCandidates().stream().anyMatch(Method::isSynthetic)) {
             throwCannotBindSynthMethod();
@@ -172,23 +172,22 @@ public MemorySegment bindTo(SegmentScope scope) {
         MethodHandle callback = null;
         try {
             callback = lookup().bind(receiver, funcName, methodType(javaReturnType, javaArgTypes));
-        } catch (NoSuchMethodException e) {
+        } catch (final NoSuchMethodException e) {
             throwCannotFindMethod(e);
-        } catch (IllegalAccessException e) {
+        } catch (final IllegalAccessException e) {
             throwCannotBindNonAccessibleMethod();
         }
 
         if (nativeReturnType.isPresent()) {
             return nativeLinker()
-                .upcallStub(callback, FunctionDescriptor.of(nativeReturnType.get(), nativeArgTypes), scope);
-        } else {
-            return nativeLinker().upcallStub(callback, FunctionDescriptor.ofVoid(nativeArgTypes), scope);
+                .upcallStub(callback, FunctionDescriptor.of(nativeReturnType.get(), nativeArgTypes), arena);
         }
+        return nativeLinker().upcallStub(callback, FunctionDescriptor.ofVoid(nativeArgTypes), arena);
     }
 
     @Override
-    public MemorySegment bindToGlobalScope() {
-        return bindTo(SegmentScope.global());
+    public MemorySegment bindToGlobalArena() {
+        return bindTo(Arena.global());
     }
 
     private List<Method> extractMethodCandidates() {
@@ -204,12 +203,11 @@ private void throwCannotBindNonAccessibleMethod() {
         throw new FluffyMemoryException("Cannot create function pointer to non accessible JVM methods.");
     }
 
-    private void throwCannotFindMethod(Throwable cause) {
-        var errMsg = "Could not find method '" + funcName + "' in type " + receiver.getClass().getCanonicalName();
+    private void throwCannotFindMethod(final Throwable cause) {
+        final var errMsg = "Could not find method '" + funcName + "' in type " + receiver.getClass().getCanonicalName();
         if (cause == null) {
             throw new FluffyMemoryException(errMsg);
-        } else {
-            throw new FluffyMemoryException(errMsg, cause);
         }
+        throw new FluffyMemoryException(errMsg, cause);
     }
 }

src/main/java/com/itemis/fluffyj/memory/FluffyMemoryPointerBuilder.java

@@ -11,7 +11,7 @@
 import com.itemis.fluffyj.memory.internal.PointerOfThing;
 import com.itemis.fluffyj.memory.internal.impl.CDataTypeConverter;
 
-import java.lang.foreign.SegmentScope;
+import java.lang.foreign.Arena;
 
 /**
  * Intermediate pointer creation helper.
@@ -24,7 +24,7 @@ public final class FluffyMemoryPointerBuilder {
      * @return A {@link FluffyMemoryScalarPointerAllocator} instance that is able to allocate
      *         pointers to data of type {@code T}.
      */
-    public <T> FluffyMemoryScalarPointerAllocator<T> to(FluffyScalarSegment<? extends T> toHere) {
+    public <T> FluffyMemoryScalarPointerAllocator<T> to(final FluffyScalarSegment<? extends T> toHere) {
         requireNonNull(toHere, "toHere");
         return new FluffyMemoryScalarPointerAllocator<>(toHere);
     }
@@ -35,7 +35,7 @@ public <T> FluffyMemoryScalarPointerAllocator<T> to(FluffyScalarSegment<? extend
      * @return A {@link FluffyMemoryScalarPointerAllocator} instance that is able to allocate
      *         pointers to data of type {@code T}.
      */
-    public <T> FluffyMemoryVectorPointerAllocator<T> toArray(FluffyVectorSegment<? extends T> toHere) {
+    public <T> FluffyMemoryVectorPointerAllocator<T> toArray(final FluffyVectorSegment<? extends T> toHere) {
         requireNonNull(toHere, "toHere");
         return new FluffyMemoryVectorPointerAllocator<>(toHere);
     }
@@ -45,7 +45,7 @@ public <T> FluffyMemoryVectorPointerAllocator<T> toArray(FluffyVectorSegment<? e
      * @return A {@link FluffyMemoryScalarPointerAllocator} instance that is able to allocate
      *         pointers to data of type {@code T}.
      */
-    public FluffyMemoryTypedPointerBuilder to(long address) {
+    public FluffyMemoryTypedPointerBuilder to(final long address) {
         requireNonNull(address, "address");
         return new FluffyMemoryTypedPointerBuilder(address);
     }
@@ -58,7 +58,7 @@ public FluffyMemoryTypedPointerBuilder to(long address) {
      * @return A new instance of {@link FluffyPointer} tied to the global scope.
      */
     public FluffyPointer allocate() {
-        return allocate(SegmentScope.global());
+        return allocate(Arena.ofAuto());
     }
 
     /**
@@ -68,11 +68,11 @@ public FluffyPointer allocate() {
      * @param scope - The scope to tie the pointer to.
      * @return A new instance of {@link FluffyPointer}.
      */
-    public FluffyPointer allocate(SegmentScope scope) {
-        return new PointerOfThing(requireNonNull(scope, "scope"));
+    public FluffyPointer allocate(final Arena arena) {
+        return new PointerOfThing(requireNonNull(arena, "arena"));
     }
 
-    public <T> FluffyMemoryScalarPointerAllocator<T> of(Class<? extends T> type) {
+    public <T> FluffyMemoryScalarPointerAllocator<T> of(final Class<? extends T> type) {
         return new FluffyMemoryTypedPointerBuilder(NULL.address()).as(type);
     }
 
@@ -82,7 +82,7 @@ public <T> FluffyMemoryScalarPointerAllocator<T> of(Class<? extends T> type) {
      * @param funcName - Name of the JVM method to point to.
      * @return A builder that helps with creating the function pointer.
      */
-    public CFuncStage toCFunc(String funcName) {
+    public CFuncStage toCFunc(final String funcName) {
         return new FluffyMemoryFuncPointerBuilder(requireNonNull(funcName, "funcName"), new CDataTypeConverter());
     }
 
@@ -93,7 +93,7 @@ public CFuncStage toCFunc(String funcName) {
      * @param funcName - Name of the JVM method to point to.
      * @return A builder that helps with creating the function pointer.
      */
-    public FuncStage toFunc(String funcName) {
+    public FuncStage toFunc(final String funcName) {
         return new FluffyMemoryFuncPointerBuilder(requireNonNull(funcName, "funcName"));
     }
 
@@ -108,7 +108,7 @@ public static final class FluffyMemoryTypedPointerBuilder {
          *
          * @param address - Created pointer will point to this address.
          */
-        public FluffyMemoryTypedPointerBuilder(long address) {
+        public FluffyMemoryTypedPointerBuilder(final long address) {
             requireNonNull(address, "address");
             this.address = address;
         }
@@ -120,14 +120,14 @@ public FluffyMemoryTypedPointerBuilder(long address) {
          * @param type - Type of scalar data to point to.
          * @return A new builder instance that helps with creating this kind of pointer.
          */
-        public <T> FluffyMemoryScalarPointerAllocator<T> as(Class<? extends T> type) {
+        public <T> FluffyMemoryScalarPointerAllocator<T> as(final Class<? extends T> type) {
             return new FluffyMemoryScalarPointerAllocator<>(address, type);
         }
 
         /**
          * @param byteSize - The size of the array the pointer shall point to in bytes.
          */
-        public FluffyMemoryTypedArrayPointerBuilder asArray(int byteSize) {
+        public FluffyMemoryTypedArrayPointerBuilder asArray(final int byteSize) {
             return new FluffyMemoryTypedArrayPointerBuilder(address, byteSize);
         }
     }
@@ -145,7 +145,7 @@ public static final class FluffyMemoryTypedArrayPointerBuilder {
          * @param address - Created pointer will point to this address.
          * @param byteSize - Size of the array to point to in bytes.
          */
-        public FluffyMemoryTypedArrayPointerBuilder(long address, long byteSize) {
+        public FluffyMemoryTypedArrayPointerBuilder(final long address, final long byteSize) {
             this.address = requireNonNull(address, "address");
             this.byteSize = byteSize;
         }
@@ -156,7 +156,7 @@ public FluffyMemoryTypedArrayPointerBuilder(long address, long byteSize) {
          * @param <T> - Component type of the array to point to.
          * @return A new builder instance that helps with creating this kind of pointer.
          */
-        public <T> FluffyMemoryVectorPointerAllocator<T> of(Class<? extends T[]> arrayType) {
+        public <T> FluffyMemoryVectorPointerAllocator<T> of(final Class<? extends T[]> arrayType) {
             return new FluffyMemoryVectorPointerAllocator<>(address, byteSize, arrayType);
         }
     }