Migrated source code from Simantics SVN

[simantics/platform.git] / bundles / org.simantics.scl.runtime / src / org / simantics / scl / runtime / procedure / RandomEffect.java

diff --git a/bundles/org.simantics.scl.runtime/src/org/simantics/scl/runtime/procedure/RandomEffect.java b/bundles/org.simantics.scl.runtime/src/org/simantics/scl/runtime/procedure/RandomEffect.java
new file mode 100755 (executable)
index 0000000..7b55a22
--- /dev/null
+++ b/bundles/org.simantics.scl.runtime/src/org/simantics/scl/runtime/procedure/RandomEffect.java
@@ -0,0 +1,31 @@
+package org.simantics.scl.runtime.procedure;\r
+\r
+import java.util.Random;\r
+\r
+import org.simantics.scl.runtime.SCLContext;\r
+import org.simantics.scl.runtime.function.Function;\r
+import org.simantics.scl.runtime.tuple.Tuple0;\r
+\r
+public class RandomEffect {\r
+    public static final String RANDOM = "random";\r
+    \r
+    public static Object withSeed(long seed, Function fun) {\r
+        SCLContext context = SCLContext.getCurrent();\r
+        Random oldRandom = (Random)context.put(RANDOM, new Random(seed));\r
+        try {\r
+            return fun.apply(Tuple0.INSTANCE);\r
+        } finally {\r
+            context.put(RANDOM, oldRandom);\r
+        }\r
+    }\r
+    \r
+    public static Object runRandom(Function fun) {\r
+        SCLContext context = SCLContext.getCurrent();\r
+        Random oldRandom = (Random)context.put(RANDOM, new Random());\r
+        try {\r
+            return fun.apply(Tuple0.INSTANCE);\r
+        } finally {\r
+            context.put(RANDOM, oldRandom);\r
+        }\r
+    }\r
+}\r