Ray will read your configurations in the following order:
- Java system properties: e.g.,
-Dray.run-mode=SINGLE_PROCESS. - A
ray.conffile in the classpath: example. - Customise your own
ray.confpath using system property-Dray.config=/path/to/ray.conf
For all available config items and default values, see this file.
Ray.init();Each remote object is considered a RayObject<T> where T is the
type for this object. You can use Ray.put and RayObject<T>.get
to write and read the objects.
Integer x = 1;
RayObject<Integer> obj = Ray.put(x);
Integer x1 = obj.get();
assert (x.equals(x1));Here is an ordinary java code piece for composing
hello world example.
public class ExampleClass {
public static void main(String[] args) {
String str1 = add("hello", "world");
String str = add(str1, "example");
System.out.println(str);
}
public static String add(String a, String b) {
return a + " " + b;
}
}We use @RayRemote to indicate that a function is remote, and use
Ray.call to invoke it. The result from the latter is a
RayObject<R> where R is the return type of the target function.
The following shows the changed example with add annotated, and
correspondent calls executed on remote machines.
public class ExampleClass {
public static void main(String[] args) {
Ray.init();
RayObject<String> objStr1 = Ray.call(ExampleClass::add, "hello", "world");
RayObject<String> objStr2 = Ray.call(ExampleClass::add, objStr1, "example");
String str = objStr2.get();
System.out.println(str);
}
@RayRemote
public static String add(String a, String b) {
return a + " " + b;
}
}