Java Exceptions Loops and deprecated (or is this a URLEncoding thing?)

I just wrote a whole ad about how I got to this point, but decided it would be easier for you to post the code and leave it there :)

As far as I can tell, the performance of test3 () should be the same as that of test1 () - the only difference is that the exception is caught (inside the calling method for test1 (), inside the called method for test3 ())

Why does test3 () regularly take time somewhere between test1 () and test2 ()?

import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;

public class Test {

    public static void main(String[] args) {
        warmup(); 
        test1(2500000); // Exception caught inside the loop
        test2(2500000); // Exception caught outside the loop
        test3(2500000); // Exception caught "inside" the loop, but in the URLEncoder.encode() method
    }

    private static void warmup() {
        // Let URLEncoder do whatever startup it needs before we hit it
        String encoding = System.getProperty("file.encoding");
        try {
            URLEncoder.encode("ignore", encoding);
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    private static void test1(int count) {
        String encoding = System.getProperty("file.encoding");
        long start = System.currentTimeMillis();
        for (int i = 0; i < count; i++) {
            try {
                URLEncoder.encode("test 1 " + i, encoding);
            } catch (UnsupportedEncodingException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        long end = System.currentTimeMillis();
        System.out.println("Performed " + count + " encodings trying to catch each in " + (end - start) + "ms");
    }

    private static void test2(int count) {
        String encoding = System.getProperty("file.encoding");
        long start = System.currentTimeMillis();
        try {
            for (int i = 0; i < count; i++) {
                URLEncoder.encode("test 2" + i, encoding);
            }
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        long end = System.currentTimeMillis();
        System.out.println("Performed " + count + " encodings trying to catch all in " + (end - start) + "ms");
    }

    private static void test3(int count) {
        long start = System.currentTimeMillis();
        for (int i = 0; i < count; i++) {
            URLEncoder.encode("test 3 " + i);
        }
        long end = System.currentTimeMillis();
        System.out.println("Performed " + count + " encodings with a deprecated method in " + (end - start) + "ms");
    }

}

      

        
        
        
      

    

Running it gives me (JDK 1.6.0_13 on Windows XP) output:

Performed 2500000 encodings trying to catch each in 4906ms
Performed 2500000 encodings trying to catch all in 2454ms
Performed 2500000 encodings with a deprecated method in 2953ms

      

        
        
        
      

    

So the answers are pretty close (we're saying something so trivial that it doesn't matter), btu I'm curious!

Further...

People suggested that JVM optimizations get in the way - I agree. So, I split each test into its own class / main method and each separately. The results of this:

1 - Performed 2500000 encodings trying to catch each in 5016ms
1 - Performed 5000000 encodings trying to catch each in 7547ms
1 - Performed 5000000 encodings trying to catch each in 7515ms
1 - Performed 5000000 encodings trying to catch each in 7531ms

2 - Performed 2500000 encodings trying to catch all in 4719ms
2 - Performed 5000000 encodings trying to catch all in 7250ms
2 - Performed 5000000 encodings trying to catch all in 7203ms
2 - Performed 5000000 encodings trying to catch all in 7250ms

3 - Performed 2500000 encodings with a deprecated method in 5297ms
3 - Performed 5000000 encodings with a deprecated method in 8015ms
3 - Performed 5000000 encodings with a deprecated method in 8063ms
3 - Performed 5000000 encodings with a deprecated method in 8219ms

      

        
        
        
      

    

Interesting observations:

• The gap between catching every call and catching everything outside of the loop is bridged in its own JVM (I suppose the optimization doesn't go all the way down the chain in the case of "all tests in one" due to other iterations that were done)
• The gap between try / trick on my side and try / catch inside URLEncoder.encode () is now much smaller (half a second over 5,000,000 iterations), but still persistently exists ...