[Java] Refine python function (#8943)

java/api/src/main/java/io/ray/api/RayCall.java

@@ -8,7 +8,7 @@ import io.ray.api.call.PyTaskCaller;
 import io.ray.api.call.TaskCaller;
 import io.ray.api.call.VoidTaskCaller;
 import io.ray.api.function.PyActorClass;
-import io.ray.api.function.PyRemoteFunction;
+import io.ray.api.function.PyFunction;
 import io.ray.api.function.RayFunc0;
 import io.ray.api.function.RayFunc1;
 import io.ray.api.function.RayFunc2;
@@ -1942,39 +1942,39 @@ class RayCall {
   // ===========================
   // Cross-language methods.
   // ===========================
-  public static <R> PyTaskCaller<R> task(PyRemoteFunction<R> pyRemoteFunction) {
+  public static <R> PyTaskCaller<R> task(PyFunction<R> pyFunction) {
     Object[] args = new Object[]{};
-    return new PyTaskCaller<>(pyRemoteFunction, args);
+    return new PyTaskCaller<>(pyFunction, args);
   }
 
-  public static <R> PyTaskCaller<R> task(PyRemoteFunction<R> pyRemoteFunction, Object obj0) {
+  public static <R> PyTaskCaller<R> task(PyFunction<R> pyFunction, Object obj0) {
     Object[] args = new Object[]{obj0};
-    return new PyTaskCaller<>(pyRemoteFunction, args);
+    return new PyTaskCaller<>(pyFunction, args);
   }
 
-  public static <R> PyTaskCaller<R> task(PyRemoteFunction<R> pyRemoteFunction, Object obj0, Object obj1) {
+  public static <R> PyTaskCaller<R> task(PyFunction<R> pyFunction, Object obj0, Object obj1) {
     Object[] args = new Object[]{obj0, obj1};
-    return new PyTaskCaller<>(pyRemoteFunction, args);
+    return new PyTaskCaller<>(pyFunction, args);
   }
 
-  public static <R> PyTaskCaller<R> task(PyRemoteFunction<R> pyRemoteFunction, Object obj0, Object obj1, Object obj2) {
+  public static <R> PyTaskCaller<R> task(PyFunction<R> pyFunction, Object obj0, Object obj1, Object obj2) {
     Object[] args = new Object[]{obj0, obj1, obj2};
-    return new PyTaskCaller<>(pyRemoteFunction, args);
+    return new PyTaskCaller<>(pyFunction, args);
   }
 
-  public static <R> PyTaskCaller<R> task(PyRemoteFunction<R> pyRemoteFunction, Object obj0, Object obj1, Object obj2, Object obj3) {
+  public static <R> PyTaskCaller<R> task(PyFunction<R> pyFunction, Object obj0, Object obj1, Object obj2, Object obj3) {
     Object[] args = new Object[]{obj0, obj1, obj2, obj3};
-    return new PyTaskCaller<>(pyRemoteFunction, args);
+    return new PyTaskCaller<>(pyFunction, args);
   }
 
-  public static <R> PyTaskCaller<R> task(PyRemoteFunction<R> pyRemoteFunction, Object obj0, Object obj1, Object obj2, Object obj3, Object obj4) {
+  public static <R> PyTaskCaller<R> task(PyFunction<R> pyFunction, Object obj0, Object obj1, Object obj2, Object obj3, Object obj4) {
     Object[] args = new Object[]{obj0, obj1, obj2, obj3, obj4};
-    return new PyTaskCaller<>(pyRemoteFunction, args);
+    return new PyTaskCaller<>(pyFunction, args);
   }
 
-  public static <R> PyTaskCaller<R> task(PyRemoteFunction<R> pyRemoteFunction, Object obj0, Object obj1, Object obj2, Object obj3, Object obj4, Object obj5) {
+  public static <R> PyTaskCaller<R> task(PyFunction<R> pyFunction, Object obj0, Object obj1, Object obj2, Object obj3, Object obj4, Object obj5) {
     Object[] args = new Object[]{obj0, obj1, obj2, obj3, obj4, obj5};
-    return new PyTaskCaller<>(pyRemoteFunction, args);
+    return new PyTaskCaller<>(pyFunction, args);
   }
 
   public static PyActorCreator actor(PyActorClass pyActorClass) {

java/api/src/main/java/io/ray/api/call/PyTaskCaller.java

@@ -2,7 +2,7 @@ package io.ray.api.call;
 
 import io.ray.api.ObjectRef;
 import io.ray.api.Ray;
-import io.ray.api.function.PyRemoteFunction;
+import io.ray.api.function.PyFunction;
 
 /**
  * A helper to call python remote function.
@@ -10,10 +10,10 @@ import io.ray.api.function.PyRemoteFunction;
  * @param <R> The type of the python function return value
  */
 public class PyTaskCaller<R> extends BaseTaskCaller<PyTaskCaller<R>> {
-  private final PyRemoteFunction<R> func;
+  private final PyFunction<R> func;
   private final Object[] args;
 
-  public PyTaskCaller(PyRemoteFunction<R> func, Object[] args) {
+  public PyTaskCaller(PyFunction<R> func, Object[] args) {
     this.func = func;
     this.args = args;
   }

java/api/src/main/java/io/ray/api/function/PyActorClass.java

@@ -18,7 +18,7 @@ package io.ray.api.function;
  * we can create this Python actor from Java:
  *
  * {@code
- * PyActorHandle actor = Ray.createActor(new PyActorClass("example_package.example_module", "A"),
+ * PyActorHandle actor = Ray.createActor(PyActorClass.of("example_package.example_module", "A"),
  *                                    "the value for x");
  * }
  * </pre>
@@ -29,8 +29,20 @@ public class PyActorClass {
   // The name of this actor class
   public final String className;
 
-  public PyActorClass(String moduleName, String className) {
+  private PyActorClass(String moduleName, String className) {
     this.moduleName = moduleName;
     this.className = className;
   }
+
+  /**
+   * Create a python actor class.
+   *
+   * @param moduleName The full module name of this actor class
+   * @param className The name of this actor class
+   * @return a python actor class
+   */
+  public static PyActorClass of(String moduleName, String className) {
+    return new PyActorClass(moduleName, className);
+  }
+
 }

java/api/src/main/java/io/ray/api/function/PyActorMethod.java

@@ -1,8 +1,8 @@
 package io.ray.api.function;
 
 /**
- * A class that represents a method of a Python actor. 
- *
+ * A class that represents a method of a Python actor.
+ * <p>
  * Note, information about the actor will be inferred from the actor handle,
  * so it's not specified in this class.
  *
@@ -24,7 +24,7 @@ package io.ray.api.function;
  *
  * {@code
  * // A.foo returns a string, so we have to set the returnType to String.class
- * ObjectRef<String> res = actor.call(new PyActorMethod<>("foo", String.class));
+ * ObjectRef<String> res = actor.call(PyActorMethod.of("foo", String.class));
  * String x = res.get();
  * }
  * </pre>
@@ -35,8 +35,31 @@ public class PyActorMethod<R> {
   // Type of the return value of this actor method
   public final Class<R> returnType;
 
-  public PyActorMethod(String methodName, Class<R> returnType) {
+  private PyActorMethod(String methodName, Class<R> returnType) {
     this.methodName = methodName;
     this.returnType = returnType;
   }
+
+  /**
+   * Create a python actor method.
+   *
+   * @param methodName The name of this actor method
+   * @return a python actor method.
+   */
+  public static PyActorMethod<Object> of(String methodName) {
+    return of(methodName, Object.class);
+  }
+
+  /**
+   * Create a python actor method.
+   *
+   * @param methodName The name of this actor method
+   * @param returnType Class of the return value of this actor method
+   * @param <R> The type of the return value of this actor method
+   * @return a python actor method.
+   */
+  public static <R> PyActorMethod<R> of(String methodName, Class<R> returnType) {
+    return new PyActorMethod<>(methodName, returnType);
+  }
+
 }

java/api/src/main/java/io/ray/api/function/PyFunction.java

@@ -0,0 +1,74 @@
+package io.ray.api.function;
+
+/**
+ * A class that represents a Python remote function.
+ *
+ * <pre>
+ * example_package/
+ * ├──__init__.py
+ * └──example_module.py
+ *
+ * in example_module.py there is a function.
+ *
+ * \@ray.remote
+ * def bar(v):
+ *     return v
+ *
+ * then we can call the Python function bar:
+ *
+ * {@code
+ * // bar returns input, so we have to set the returnType to int.class if bar accepts an int
+ * ObjectRef<Integer> res = actor.call(
+ *    PyFunction.of("example_package.example_module", "bar", Integer.class),
+ *    1);
+ * Integer value = res.get();
+ *
+ * // bar returns input, so we have to set the returnType to String.class if bar accepts a string
+ * ObjectRef<String> res = actor.call(
+ *    PyFunction.of("example_package.example_module", "bar", String.class),
+ *    "Hello world!");
+ * String value = res.get();
+ * }
+ * </pre>
+ */
+public class PyFunction<R> {
+  // The full module name of this function
+  public final String moduleName;
+  // The name of this function
+  public final String functionName;
+  // Type of the return value of this function
+  public final Class<R> returnType;
+
+  private PyFunction(String moduleName, String functionName, Class<R> returnType) {
+    this.moduleName = moduleName;
+    this.functionName = functionName;
+    this.returnType = returnType;
+  }
+
+  /**
+   * Create a python function.
+   *
+   * @param moduleName The full module name of this function
+   * @param functionName The name of this function
+   * @return a python function.
+   */
+  public static PyFunction<Object> of(
+      String moduleName, String functionName) {
+    return of(moduleName, functionName, Object.class);
+  }
+
+  /**
+   * Create a python function.
+   *
+   * @param moduleName The full module name of this function
+   * @param functionName The name of this function
+   * @param returnType Class of the return value of this function
+   * @param <R> Type of the return value of this function
+   * @return a python function.
+   */
+  public static <R> PyFunction<R> of(
+      String moduleName, String functionName, Class<R> returnType) {
+    return new PyFunction<>(moduleName, functionName, returnType);
+  }
+
+}

java/api/src/main/java/io/ray/api/function/PyRemoteFunction.java

@@ -1,47 +0,0 @@
-package io.ray.api.function;
-
-/**
- * A class that represents a Python remote function.
- *
- * <pre>
- * example_package/
- * ├──__init__.py
- * └──example_module.py
- *
- * in example_module.py there is a function.
- *
- * \@ray.remote
- * def bar(v):
- *     return v
- *
- * then we can call the Python function bar:
- *
- * {@code
- * // bar returns input, so we have to set the returnType to int.class if bar accepts an int
- * ObjectRef<Integer> res = actor.call(
- *    new PyRemoteFunction<>("example_package.example_module", "bar", Integer.class),
- *    1);
- * Integer value = res.get();
- *
- * // bar returns input, so we have to set the returnType to String.class if bar accepts a string
- * ObjectRef<String> res = actor.call(
- *    new PyRemoteFunction<>("example_package.example_module", "bar", String.class),
- *    "Hello world!");
- * String value = res.get();
- * }
- * </pre>
- */
-public class PyRemoteFunction<R> {
-  // The full module name of this function
-  public final String moduleName;
-  // The name of this function
-  public final String functionName;
-  // Type of the return value of this function
-  public final Class<R> returnType;
-
-  public PyRemoteFunction(String moduleName, String functionName, Class<R> returnType) {
-    this.moduleName = moduleName;
-    this.functionName = functionName;
-    this.returnType = returnType;
-  }
-}

java/api/src/main/java/io/ray/api/runtime/RayRuntime.java

@@ -7,7 +7,7 @@ import io.ray.api.PyActorHandle;
 import io.ray.api.WaitResult;
 import io.ray.api.function.PyActorClass;
 import io.ray.api.function.PyActorMethod;
-import io.ray.api.function.PyRemoteFunction;
+import io.ray.api.function.PyFunction;
 import io.ray.api.function.RayFunc;
 import io.ray.api.id.ObjectId;
 import io.ray.api.id.UniqueId;
@@ -103,12 +103,12 @@ public interface RayRuntime {
   /**
    * Invoke a remote Python function.
    *
-   * @param pyRemoteFunction The Python function.
+   * @param pyFunction The Python function.
    * @param args Arguments of the function.
    * @param options The options for this call.
    * @return The result object.
    */
-  ObjectRef call(PyRemoteFunction pyRemoteFunction, Object[] args, CallOptions options);
+  ObjectRef call(PyFunction pyFunction, Object[] args, CallOptions options);
 
   /**
    * Invoke a remote function on an actor.

java/runtime/src/main/java/io/ray/runtime/AbstractRayRuntime.java

@@ -11,7 +11,7 @@ import io.ray.api.WaitResult;
 import io.ray.api.exception.RayException;
 import io.ray.api.function.PyActorClass;
 import io.ray.api.function.PyActorMethod;
-import io.ray.api.function.PyRemoteFunction;
+import io.ray.api.function.PyFunction;
 import io.ray.api.function.RayFunc;
 import io.ray.api.id.ObjectId;
 import io.ray.api.options.ActorCreationOptions;
@@ -107,15 +107,14 @@ public abstract class AbstractRayRuntime implements RayRuntimeInternal {
   }
 
   @Override
-  public ObjectRef call(PyRemoteFunction pyRemoteFunction, Object[] args,
-                        CallOptions options) {
+  public ObjectRef call(PyFunction pyFunction, Object[] args, CallOptions options) {
     PyFunctionDescriptor functionDescriptor = new PyFunctionDescriptor(
-        pyRemoteFunction.moduleName,
+        pyFunction.moduleName,
         "",
-        pyRemoteFunction.functionName);
+        pyFunction.functionName);
     // Python functions always have a return value, even if it's `None`.
     return callNormalFunction(functionDescriptor, args,
-        /*returnType=*/Optional.of(pyRemoteFunction.returnType), options);
+        /*returnType=*/Optional.of(pyFunction.returnType), options);
   }
 
   @Override

java/runtime/src/main/java/io/ray/runtime/util/generator/RayCallGenerator.java

@@ -29,7 +29,7 @@ public class RayCallGenerator extends BaseGenerator {
     newLine("import io.ray.api.call.TaskCaller;");
     newLine("import io.ray.api.call.VoidTaskCaller;");
     newLine("import io.ray.api.function.PyActorClass;");
-    newLine("import io.ray.api.function.PyRemoteFunction;");
+    newLine("import io.ray.api.function.PyFunction;");
     for (int i = 0; i <= MAX_PARAMETERS; i++) {
       newLine("import io.ray.api.function.RayFunc" + i + ";");
     }
@@ -273,8 +273,8 @@ public class RayCallGenerator extends BaseGenerator {
       paramPrefix += "PyActorMethod<R> pyActorMethod";
       funcArgs += "pyActorMethod";
     } else {
-      paramPrefix += "PyRemoteFunction<R> pyRemoteFunction";
-      funcArgs += "pyRemoteFunction";
+      paramPrefix += "PyFunction<R> pyFunction";
+      funcArgs += "pyFunction";
     }
     if (numParameters > 0) {
       paramPrefix += ", ";

java/test/src/main/java/io/ray/test/CrossLanguageInvocationTest.java

@@ -8,7 +8,7 @@ import io.ray.api.PyActorHandle;
 import io.ray.api.Ray;
 import io.ray.api.function.PyActorClass;
 import io.ray.api.function.PyActorMethod;
-import io.ray.api.function.PyRemoteFunction;
+import io.ray.api.function.PyFunction;
 import io.ray.runtime.actor.NativeActorHandle;
 import io.ray.runtime.actor.NativePyActorHandle;
 import java.io.File;
@@ -70,7 +70,7 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
         "example binary".getBytes()};  // byte[]
     for (Object o : inputs) {
       ObjectRef res = Ray.task(
-          new PyRemoteFunction<>(PYTHON_MODULE, "py_return_input", o.getClass()),
+          PyFunction.of(PYTHON_MODULE, "py_return_input", o.getClass()),
           o).remote();
       Assert.assertEquals(res.get(), o);
     }
@@ -78,7 +78,7 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
     {
       Object input = null;
       ObjectRef<Object> res = Ray.task(
-          new PyRemoteFunction<>(PYTHON_MODULE, "py_return_input", Object.class), input).remote();
+          PyFunction.of(PYTHON_MODULE, "py_return_input", Object.class), input).remote();
       Object r = res.get();
       Assert.assertEquals(r, input);
     }
@@ -86,7 +86,7 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
     {
       int[] input = new int[]{1, 2};
       ObjectRef<int[]> res = Ray.task(
-          new PyRemoteFunction<>(PYTHON_MODULE, "py_return_input", int[].class), input).remote();
+          PyFunction.of(PYTHON_MODULE, "py_return_input", int[].class), input).remote();
       int[] r = res.get();
       Assert.assertEquals(r, input);
     }
@@ -95,7 +95,7 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
       Object[] input = new Object[]{1, 2.3f, 4.56, "789", "10".getBytes(), null, true,
           new int[]{1, 2}};
       ObjectRef<Object[]> res = Ray.task(
-          new PyRemoteFunction<>(PYTHON_MODULE, "py_return_input", Object[].class), input).remote();
+          PyFunction.of(PYTHON_MODULE, "py_return_input", Object[].class), input).remote();
       Object[] r = res.get();
       // If we tell the value type is Object, then all numbers will be Number type.
       Assert.assertEquals(((Number) r[0]).intValue(), input[0]);
@@ -120,7 +120,7 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
       Assert.expectThrows(Exception.class, () -> {
         List<Integer> input = Arrays.asList(1, 2);
         ObjectRef<List<Integer>> res = Ray.task(
-            new PyRemoteFunction<>(PYTHON_MODULE, "py_return_input",
+            PyFunction.of(PYTHON_MODULE, "py_return_input",
                 (Class<List<Integer>>) input.getClass()), input).remote();
         List<Integer> r = res.get();
         Assert.assertEquals(r, input);
@@ -130,7 +130,7 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
 
   @Test
   public void testPythonCallJavaFunction() {
-    ObjectRef<String> res = Ray.task(new PyRemoteFunction<>(
+    ObjectRef<String> res = Ray.task(PyFunction.of(
         PYTHON_MODULE, "py_func_call_java_function", String.class)).remote();
     Assert.assertEquals(res.get(), "success");
   }
@@ -138,9 +138,9 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
   @Test
   public void testCallingPythonActor() {
     PyActorHandle actor = Ray.actor(
-        new PyActorClass(PYTHON_MODULE, "Counter"), "1".getBytes()).remote();
+        PyActorClass.of(PYTHON_MODULE, "Counter"), "1".getBytes()).remote();
     ObjectRef<byte[]> res = actor.task(
-        new PyActorMethod<>("increase", byte[].class),
+        PyActorMethod.of("increase", byte[].class),
         "1".getBytes()).remote();
     Assert.assertEquals(res.get(), "2".getBytes());
   }
@@ -148,7 +148,7 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
   @Test
   public void testPythonCallJavaActor() {
     ObjectRef<byte[]> res = Ray.task(
-        new PyRemoteFunction<>(PYTHON_MODULE, "py_func_call_java_actor", byte[].class),
+        PyFunction.of(PYTHON_MODULE, "py_func_call_java_actor", byte[].class),
         "1".getBytes()).remote();
     Assert.assertEquals(res.get(), "Counter1".getBytes());
 
@@ -158,7 +158,7 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
   public void testPassActorHandleFromPythonToJava() {
     // Call a python function which creates a python actor
     // and pass the actor handle to callPythonActorHandle.
-    ObjectRef<byte[]> res = Ray.task(new PyRemoteFunction<>(
+    ObjectRef<byte[]> res = Ray.task(PyFunction.of(
         PYTHON_MODULE, "py_func_pass_python_actor_handle", byte[].class)).remote();
     Assert.assertEquals(res.get(), "3".getBytes());
   }
@@ -170,18 +170,18 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
     Preconditions.checkState(javaActor instanceof NativeActorHandle);
     byte[] actorHandleBytes = ((NativeActorHandle) javaActor).toBytes();
     ObjectRef<byte[]> res = Ray.task(
-        new PyRemoteFunction<>(PYTHON_MODULE,
+        PyFunction.of(PYTHON_MODULE,
             "py_func_call_java_actor_from_handle",
             byte[].class),
         actorHandleBytes).remote();
     Assert.assertEquals(res.get(), "12".getBytes());
     // Create a python actor, and pass actor handle to python.
     PyActorHandle pyActor = Ray.actor(
-        new PyActorClass(PYTHON_MODULE, "Counter"), "1".getBytes()).remote();
+        PyActorClass.of(PYTHON_MODULE, "Counter"), "1".getBytes()).remote();
     Preconditions.checkState(pyActor instanceof NativeActorHandle);
     actorHandleBytes = ((NativeActorHandle) pyActor).toBytes();
     res = Ray.task(
-        new PyRemoteFunction<>(PYTHON_MODULE,
+        PyFunction.of(PYTHON_MODULE,
             "py_func_call_python_actor_from_handle",
             byte[].class),
         actorHandleBytes).remote();
@@ -221,7 +221,7 @@ public class CrossLanguageInvocationTest extends BaseMultiLanguageTest {
     // This function will be called from test_cross_language_invocation.py
     NativePyActorHandle actor = (NativePyActorHandle) NativeActorHandle.fromBytes(value);
     ObjectRef<byte[]> res = actor.task(
-        new PyActorMethod<>("increase", byte[].class),
+        PyActorMethod.of("increase", byte[].class),
         "1".getBytes()).remote();
     Assert.assertEquals(res.get(), "3".getBytes());
     return (byte[]) res.get();

java/test/src/main/java/io/ray/test/RaySerializerTest.java

@@ -13,7 +13,7 @@ public class RaySerializerTest extends BaseMultiLanguageTest {
   @Test
   public void testSerializePyActor() {
     PyActorHandle pyActor = Ray.actor(
-        new PyActorClass("test", "RaySerializerTest")).remote();
+        PyActorClass.of("test", "RaySerializerTest")).remote();
     NativeRayObject nativeRayObject = ObjectSerializer.serialize(pyActor);
     PyActorHandle result = (PyActorHandle) ObjectSerializer
         .deserialize(nativeRayObject, null, Object.class);