11.10 Map

src/concurrency/Fat.java

@@ -0,0 +1,16 @@
+package concurrency;//: concurrency/Fat.java
+// Objects that are expensive to create.
+
+public class Fat {
+  private volatile double d; // Prevent optimization
+  private static int counter = 0;
+  private final int id = counter++;
+  public Fat() {
+    // Expensive, interruptible operation:
+    for(int i = 1; i < 10000; i++) {
+      d += (Math.PI + Math.E) / (double)i;
+    }
+  }
+  public void operation() { System.out.println(this); }
+  public String toString() { return "Fat id: " + id; }
+} ///:~