//: containers/ListPerformance.java // ©2015 MindView LLC: see Copyright.txt // Demonstrates performance differences in Lists. // {Args: 100 500} Small to keep build testing short import java.util.*; import net.mindview.util.*; public class ListPerformance { static Random rand = new Random(); static int reps = 1000; static List>> tests = new ArrayList<>(); static List>> qTests = new ArrayList<>(); static { tests.add(new Test>("add") { @Override int test(List list, TestParam tp) { int loops = tp.loops; int listSize = tp.size; for(int i = 0; i < loops; i++) { list.clear(); for(int j = 0; j < listSize; j++) list.add(j); } return loops * listSize; } }); tests.add(new Test>("get") { @Override int test(List list, TestParam tp) { int loops = tp.loops * reps; int listSize = list.size(); for(int i = 0; i < loops; i++) list.get(rand.nextInt(listSize)); return loops; } }); tests.add(new Test>("set") { @Override int test(List list, TestParam tp) { int loops = tp.loops * reps; int listSize = list.size(); for(int i = 0; i < loops; i++) list.set(rand.nextInt(listSize), 47); return loops; } }); tests.add(new Test>("iteradd") { @Override int test(List list, TestParam tp) { final int LOOPS = 1000000; int half = list.size() / 2; ListIterator it = list.listIterator(half); for(int i = 0; i < LOOPS; i++) it.add(47); return LOOPS; } }); tests.add(new Test>("insert") { @Override int test(List list, TestParam tp) { int loops = tp.loops; for(int i = 0; i < loops; i++) list.add(5, 47); // Minimize random-access cost return loops; } }); tests.add(new Test>("remove") { @Override int test(List list, TestParam tp) { int loops = tp.loops; int size = tp.size; for(int i = 0; i < loops; i++) { list.clear(); list.addAll(new CountingIntegerList(size)); while(list.size() > 5) list.remove(5); // Minimize random-access cost } return loops * size; } }); // Tests for queue behavior: qTests.add(new Test>("addFirst") { @Override int test(LinkedList list, TestParam tp) { int loops = tp.loops; int size = tp.size; for(int i = 0; i < loops; i++) { list.clear(); for(int j = 0; j < size; j++) list.addFirst(47); } return loops * size; } }); qTests.add(new Test>("addLast") { @Override int test(LinkedList list, TestParam tp) { int loops = tp.loops; int size = tp.size; for(int i = 0; i < loops; i++) { list.clear(); for(int j = 0; j < size; j++) list.addLast(47); } return loops * size; } }); qTests.add( new Test>("rmFirst") { @Override int test(LinkedList list, TestParam tp) { int loops = tp.loops; int size = tp.size; for(int i = 0; i < loops; i++) { list.clear(); list.addAll(new CountingIntegerList(size)); while(list.size() > 0) list.removeFirst(); } return loops * size; } }); qTests.add(new Test>("rmLast") { @Override int test(LinkedList list, TestParam tp) { int loops = tp.loops; int size = tp.size; for(int i = 0; i < loops; i++) { list.clear(); list.addAll(new CountingIntegerList(size)); while(list.size() > 0) list.removeLast(); } return loops * size; } }); } static class ListTester extends Tester> { public ListTester(List container, List>> tests) { super(container, tests); } // Fill to the appropriate size before each test: @Override protected List initialize(int size){ container.clear(); container.addAll(new CountingIntegerList(size)); return container; } // Convenience method: public static void run(List list, List>> tests) { new ListTester(list, tests).timedTest(); } } public static void main(String[] args) { if(args.length > 0) Tester.defaultParams = TestParam.array(args); // Can only do these two tests on an array: Tester> arrayTest = new Tester>(null, tests.subList(1, 3)){ // This is called before each test. It // produces a non-resizeable array-backed list: @Override protected List initialize(int size) { Integer[] ia = Generated.array(Integer.class, new CountingGenerator.Integer(), size); return Arrays.asList(ia); } }; arrayTest.setHeadline("Array as List"); arrayTest.timedTest(); Tester.defaultParams= TestParam.array( 10, 5000, 100, 5000, 1000, 1000, 10000, 200); if(args.length > 0) Tester.defaultParams = TestParam.array(args); ListTester.run(new ArrayList<>(), tests); ListTester.run(new LinkedList<>(), tests); ListTester.run(new Vector<>(), tests); Tester.fieldWidth = 12; Tester> qTest = new Tester>( new LinkedList<>(), qTests); qTest.setHeadline("Queue tests"); qTest.timedTest(); } } /* Output: (Sample) --- Array as List --- size get set 10 130 183 100 130 164 1000 129 165 10000 129 165 --------------------- ArrayList --------------------- size add get set iteradd insert remove 10 121 139 191 435 3952 446 100 72 141 191 247 3934 296 1000 98 141 194 839 2202 923 10000 122 144 190 6880 14042 7333 --------------------- LinkedList --------------------- size add get set iteradd insert remove 10 182 164 198 658 366 262 100 106 202 230 457 108 201 1000 133 1289 1353 430 136 239 10000 172 13648 13187 435 255 239 ----------------------- Vector ----------------------- size add get set iteradd insert remove 10 129 145 187 290 3635 253 100 72 144 190 263 3691 292 1000 99 145 193 846 2162 927 10000 108 145 186 6871 14730 7135 -------------------- Queue tests -------------------- size addFirst addLast rmFirst rmLast 10 199 163 251 253 100 98 92 180 179 1000 99 93 216 212 10000 111 109 262 384 *///:~