Scala和Java的循环性能对比

object TestScalaPerformance {
//循环次数
var maxindex = 10000
def testFor(): Unit = {
var sum = 0
var beg = System.currentTimeMillis()
for (i <- 0 to  maxindex)
sum += i
var end = System.currentTimeMillis()
println("Scala的" + maxindex + "次for循环耗时: " + (end - beg))
}

def testWhile(): Unit = {
var sum = 0
var i = 0;
var beg = System.currentTimeMillis()
while (i < maxindex) {
i += 1
sum += i
}
var end = System.currentTimeMillis()
println("Scala的" + maxindex + "次while循环耗时: " + (end - beg))
}

def main(args: Array[String]) {
testWhile()
testFor()
}
}

public class TestJavaPerformance {
//循环次数
private static long maxindex = 10000;

public static void main(String[] args) {
testWhile();
testFor();
}

public static void testWhile() {
int i = 0;
int sum = 0;
long begtime = System.currentTimeMillis();
while(i < maxindex){
i++;
sum += i;
}
long endtime = System.currentTimeMillis();
System.out.println("Java的" + maxindex + "次while循环耗时: " + (endtime - begtime) );
}

public static void testFor() {
int i = 0;
int sum = 0;
long begtime = System.currentTimeMillis();
for (i = 0 ; i < maxindex; i++)
sum += i;
long endtime = System.currentTimeMillis();
System.out.println("Java的" + maxindex + "次for循环耗时: " + (endtime - begtime) );
}
}