日期:2014-05-20 浏览次数:20675 次
public class StringTest{
public static void main(String args[]){
long startTime1 = System.currentTimeMillis();
String text = "";
for(int i=0;i<10000;i++){
text+=i;
}
System.out.println(System.currentTimeMillis()-startTime1);
long startTime2 = System.currentTimeMillis();
StringBuffer textBuffer = new StringBuffer("");
for(int i=0;i<10000;i++){
textBuffer.append(i);
}
System.out.println((System.currentTimeMillis()-startTime2));
long startTime3 = System.currentTimeMillis();
StringBuilder textBuilder = new StringBuilder("");
for(int i=0;i<10000;i++){
textBuilder.append(i);
}
System.out.println((System.currentTimeMillis()-startTime3));
}
}
public class StringTest{
public static void main(String args[]){
int max = 1000000; //如果内存足够大,可以改成 max = Integer.MAX_VALUE;
// long startTime1 = System.currentTimeMillis();
// String text = "";
// for(int i=0;i<10000;i++){
// text+=i; //这个就不用测了,大家都知道这种是效率最低的
// }
// System.out.println(System.currentTimeMillis()-startTime1);
long startTime2 = System.currentTimeMillis();
StringBuffer textBuffer = new StringBuffer("");
for(int i=0;i<max;i++){
textBuffer.append(i);
}
System.out.println((System.currentTimeMillis()-startTime2));
long startTime3 = System.currentTimeMillis();
StringBuilder textBuilder = new StringBuilder("");
for(int i=0;i<max;i++){
textBuilder.append(i);
}
System.out.println((System.currentTimeMillis()-startTime3));
}
}