1 files changed, 52 insertions, 0 deletions
diff --git a/uitest/src/com/vaadin/tests/util/PortableRandom.java b/uitest/src/com/vaadin/tests/util/PortableRandom.java
new file mode 100644
index 0000000000..b66bdfdcaf
--- /dev/null
+++ b/uitest/src/com/vaadin/tests/util/PortableRandom.java
@@ -0,0 +1,52 @@
+package com.vaadin.tests.util;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+public class PortableRandom {
+    private final static long multiplier = 0x5DEECE66DL;
+    private final static long addend = 0xBL;
+    private final static long mask = (1L << 48) - 1;
+    private AtomicLong seed;
+
+    public PortableRandom(long seed) {
+        this.seed = new AtomicLong(0L);
+        setSeed(seed);
+    }
+
+    synchronized public void setSeed(long seed) {
+        seed = (seed ^ multiplier) & mask;
+        this.seed.set(seed);
+    }
+
+    public int nextInt(int n) {
+        if (n <= 0) {
+            throw new IllegalArgumentException("n must be positive");
+        }
+
+        if ((n & -n) == n) {
+            return (int) ((n * (long) next(31)) >> 31);
+        }
+
+        int bits, val;
+        do {
+            bits = next(31);
+            val = bits % n;
+        } while (bits - val + (n - 1) < 0);
+        return val;
+    }
+
+    protected int next(int bits) {
+        long oldseed, nextseed;
+        AtomicLong seed = this.seed;
+        do {
+            oldseed = seed.get();
+            nextseed = (oldseed * multiplier + addend) & mask;
+        } while (!seed.compareAndSet(oldseed, nextseed));
+        return (int) (nextseed >>> (48 - bits));
+    }
+
+    public boolean nextBoolean() {
+        return next(1) != 0;
+    }
+
+}
+\ No newline at end of file