Differences

This shows you the differences between two versions of the page.

--- at:tutorial:symbiosis [2007/06/20 10:51] – jdedecker
+++ at:tutorial:symbiosis [2007/06/20 14:36] – jdedecker
@@ Line 66: / Line 66: @@
 ==== Invoking AmbientTalk methods in Java ====
-When an AmbientTalk object is passed as an argument to a Java method expecting an object of an interface type, the AmbientTalk object will appear to Java objects as a regular Java object implementing that interface. Hence, messages sent to this wrapped AmbientTalk object appear as regular Java method invocations on an interface type. For example, the action listener in the chat example can be notified as if it were a normal Java object by performing **listener.actionPerformed(event)**.
+Besides calling Java methods from within AmbientTalk it is also possible to call AmbientTalk methods from within Java.  To illustrate this consider the code snippet shown below.  The **SymbiosisDemo** class is loaded and an instance is assigned to **javaDemo** variable.  The method **run** is invoked on this object and an AmbientTalk object **atObject** is passed as its argument.
+<code>
+def SymbiosisDemo := jlobby.at.tutorial.SymbiosisDemo;
+def showSymbiosis() {
+	def javaDemo := SymbiosisDemo.new();
+	def atObject := object: {
+		def ping() {
+          system.println("ping!");
+          javaDemo.run2(self);
+        };
+		def pong() {
+          system.println("pong!");
+
+        }
+	};
+	javaDemo.run(atObject);
+};
+self
+</code>
+When an AmbientTalk object is passed as an argument to a Java method expecting an object of an interface type, the AmbientTalk object will appear to Java objects as a regular Java object implementing that interface.  In the example the Java interface **PingPong** contains the two methods **ping** and **pong** that were defined in **atObject**.  This interface is also the type of the Java method **run**.  Hence, messages sent to this wrapped AmbientTalk object appear as regular Java method invocations on an interface type.  Also, note the return type of the methods **ping** and **pong**: since the AmbientTalk implementation of **pong** returns an integer, which is also the return value of the method **ping**.
+<code>
+package at.tutorial;
+public class SymbiosisDemo {
+	public interface PingPong {
+		public int ping();
+		public int pong();
+	}
+	public int run(PingPong pp) {
+		return pp.ping();
+	}
+	public int run2(PingPong pp) {
+		return pp.pong();
+	}
+}
+</code>
 If Java invokes a method declared in an interface with an overloaded method signature, all overloaded invocations are transformed into the same method invocation on the AmbientTalk object. In other words, the AmbientTalk object does not take the types into consideration. However, if the Java method is overloaded based on arity, the AmbientTalk programmer can take this into account in the parameter list of the corresponding AmbientTalk method, by means of a variable-argument list or optional parameters. Otherwise, the Java invocation may fail because of an arity mismatch.
-==== Conversions ====
 ==== Thread-Actor Symbiosis ====