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--- java_8_functions [2017/06/22 09:48]
+++ java_8_functions [2021/04/05 11:23] (current)
@@ Line 1: / Line 1: @@
+====== Functions ======
+===== Function with no Parameter and No Return Value =====
+You can just use the ''Runnable'' interface as a way for a callback. ''Runnable'' also has the ''FunctionalInterface'' annotation and as such is a valid interface for a Java 8 function.
+Interface:
+<sxh java>
+    void delete(int id, Runnable callback);
+</sxh>
+Caller:
+<sxh java>
+    delete(id, () -> {
+        // do some stuff like return data from a REST service
+        response.noContent().build();
+    });
+</sxh>
+Callee:
+<sxh java>
+    public void delete(int id, Runnable callback) {
+      getConnection(connection -> {
+          connection.delete(id, result -> {
+              if (result.success()) {
+                  callback.run();
+              }
+              else {
+                  throw result.cause();
+              }
+          });
+      });
+</sxh>
+{{tag> devel java}}