int in2 = 0;
for (int i = 0; i < iterations; i++) {
double x = 2.0 * Math.random() - 1.0, y = 2.0 * Math.random() - 1.0;
if ((Math.sqrt(x * x + y * y) < 1.0)) {
in2++;
}
}
double data2 = 4.0 * in2 / iterations;
peer.send(masterTask, new DoubleWritable(data2));
peer.sync();
if (peer.getPeerName().equals(masterTask)) {
double pi2 = 0.0;
int numPeers = peer.getNumCurrentMessages();
DoubleWritable received;
while ((received = peer.getCurrentMessage()) != null) {
pi2 += received.get();
}
pi2 = pi2 / numPeers;
peer.write(new Text("Estimated value2 of PI is"),
new DoubleWritable(pi2));
}
peer.sync();
}
@Override
public void setup(
BSPPeer<NullWritable, NullWritable, Text, DoubleWritable, DoubleWritable> peer)
throws IOException {
// Choose one as a master
this.masterTask = peer.getPeerName(peer.getNumPeers() / 2);
}
@Override
public void cleanup(
BSPPeer<NullWritable, NullWritable, Text, DoubleWritable, DoubleWritable> peer)
throws IOException {
// if (peer.getPeerName().equals(masterTask)) {
// double pi = 0.0;
// int numPeers = peer.getNumCurrentMessages();
// DoubleWritable received;
// while ((received = peer.getCurrentMessage()) != null) {
// pi += received.get();
// }
//
// pi = pi / numPeers;
// peer.write(new Text("Estimated value of PI is"),
// new DoubleWritable(pi));
// }
}
}
static void printOutput(HamaConfiguration conf) throws IOException {
FileSystem fs = FileSystem.get(conf);
FileStatus[] files = fs.listStatus(TMP_OUTPUT);
for (int i = 0; i < files.length; i++) {
if (files[i].getLen() > 0) {
FSDataInputStream in = fs.open(files[i].getPath());
IOUtils.copyBytes(in, System.out, conf, false);
in.close();
break;
}
}
fs.delete(TMP_OUTPUT, true);
}
public static void main(String[] args) throws InterruptedException,
IOException, ClassNotFoundException {
// BSP job configuration
HamaConfiguration conf = new HamaConfiguration();
BSPJob bsp = new BSPJob(conf, PiEstimator.class);
// Set the job name
bsp.setJobName("Pi Estimation Example");
bsp.setBspClass(MyEstimator.class);
bsp.setInputFormat(NullInputFormat.class);
bsp.setOutputKeyClass(Text.class);
bsp.setOutputValueClass(DoubleWritable.class);
bsp.setOutputFormat(TextOutputFormat.class);
FileOutputFormat.setOutputPath(bsp, TMP_OUTPUT);
BSPJobClient jobClient = new BSPJobClient(conf);
ClusterStatus cluster = jobClient.getClusterStatus(true);