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Groovy是否可能在我的應用程序中每隔一段時間都沒有自動複選框?Groovy在原語上非常慢
下面的代碼...
public class SumTest {
public static void main(String[] args) {
long[] longs = new long[100000000];
long nanoStart = System.nanoTime();
long counter = 1;
for (int i = 0; i < longs.length; i++) {
longs[i] = counter++;
}
double msPop = (System.nanoTime() - nanoStart)/1000000d;
System.out.println("Time taken, population: " + msPop + "ms.");
nanoStart = System.nanoTime();
long sum = 0;
for (int i = 0; i < longs.length; i++) {
sum += longs[i];
}
double msSum = (System.nanoTime() - nanoStart)/1000000d;
System.out.println("Time taken, sum: " + msSum + "ms, total: " + (msPop + msSum) + "ms");
System.out.println(" (sum: " + sum + ")");
}
}
...展品截然不同的運行時間從時 '的.java' 更名爲 '.groovy作爲':
的Java:
Time taken, population: 94.793746ms.
Time taken, sum: 65.172605ms, total: 159.966351ms
(sum: 5000000050000000)
Groovy:
Time taken, population: 2233.995965ms.
Time taken, sum: 2203.64302ms, total: 4437.638985ms
(sum: 5000000050000000)
..這是一個約30倍的差異。
的局勢加劇當我堅持長遠目標內(如在我真正的代碼的情況下):
public class SumTest {
static class Holder {
long l;
Holder(long l) { this.l = l; }
long getL() { return l; }
}
public static void main(String[] args) {
Holder[] longs = new Holder[100000000];
long nanoStart = System.nanoTime();
long counter = 1;
for (int i = 0; i < longs.length; i++) {
longs[i] = new Holder(counter++);
}
double msPop = (System.nanoTime() - nanoStart)/1000000d;
System.out.println("Time taken, population: " + msPop + "ms.");
nanoStart = System.nanoTime();
long sum = 0;
for (int i = 0; i < longs.length; i++) {
sum += longs[i].getL();
}
double msSum = (System.nanoTime() - nanoStart)/1000000d;
System.out.println("Time taken, sum: " + msSum + "ms, total: " + (msPop + msSum) + "ms");
System.out.println(" (sum: " + sum + ")");
}
}
運行時間(請注意,我用-Xms16384M -Xmx16384M運行這裏) :
的Java
Time taken, population: 1083.784927ms.
Time taken, sum: 180.518991ms, total: 1264.3039179999998ms
(sum: 5000000050000000)
的Groovy:
Time taken, population: 9816.007447ms.
Time taken, sum: 8685.506864ms, total: 18501.514311ms
(sum: 5000000050000000)
..其總數是~15倍,,但最重要的區別來自實際使用這些對象(由總和表示):〜50x。
這可以以某種方式固定嗎?當涉及操作只有涉及原語和原始操作時,我可以哄Groovy不自動包含涉及原語的每個操作嗎?
'@ CompileStatic'會做你想做的事,但它也做得更多。這意味着你完全繞過了groovy的所有動態特性。這在很多情況下可以帶來很大的性能提升。雖然依賴於動態方法和屬性的語言有很多功能,並且不能用於@CompileStatic。只是FYI。 – allTwentyQuestions