From charlesreid1

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==Comparing Hombrew Data Containers to Java Collections API==
==Comparing Hombrew Data Containers to Java Collections API==


In the Java repository ([http://git.charlesreid1.com/cs/java link] in the lists/linked-lists folder ([https://charlesreid1.com:3000/cs/java/src/master/lists/linked-lists link]), there is a timing script ([https://charlesreid1.com:3000/cs/java/src/master/lists/linked-lists/Timing.java link]) that demonstrates a simple comparison of the built-in linked list type to a trimmed down generic TLinkedList type ([https://charlesreid1.com:3000/cs/java/src/master/lists/linked-lists/TLinkedList.java link]).
In the Java repository ([http://git.charlesreid1.com/cs/java link]) in the lists/linked-lists folder ([https://charlesreid1.com:3000/cs/java/src/master/lists/linked-lists link]), there is a timing script ([https://charlesreid1.com:3000/cs/java/src/master/lists/linked-lists/Timing.java link]) that demonstrates a simple comparison of the built-in linked list type to a trimmed down generic TLinkedList type ([https://charlesreid1.com:3000/cs/java/src/master/lists/linked-lists/TLinkedList.java link]).


==Flags==
==Flags==

Revision as of 01:52, 5 June 2017

If you want an extremely detailed picture of how much time you're spending in the various parts of your code, you can use a profiler: see Java/Profiling

Basic Timing in Java: Builtin Methods

If you just want to see how much time a piece of code takes to execute, you can use Java's built in time functionality:

long start = System.nanoTime();
doStuff();
long end = System.nanoTime();
long duration = end - start;
System.out.printf("Elapsed time: %03f s\n", duration/1E9);


Timing Snippets of Code

Can make a Stopwatch class that does the following:

  • Constructor creates a new "start" variable - the stopwatch class measures time starting at its own creation
  • Can call elapsed() method to get elapsed seconds

Via http://introcs.cs.princeton.edu/java/32class/Stopwatch.java.html

public class Stopwatch {
    public Stopwatch() { 
        this.start = System.currentTimeMillis();
    }
    public double elapsed() {
        this.end = System.currentTimeMillis();
        return (end-start)/1000.0;
    }
}


Comparing Hombrew Data Containers to Java Collections API

In the Java repository (link) in the lists/linked-lists folder (link), there is a timing script (link) that demonstrates a simple comparison of the built-in linked list type to a trimmed down generic TLinkedList type (link).

Flags