public class test
long end1 = system.currenttimemillis();
long time1 = end1 -start1;
system.out.println("用string+=拼接字串的時間"+time1);
long start2 = system.currenttimemillis();
string s2 = new string("hello");
for (long i = 0; i < n; i++)
long end2 = system.currenttimemillis();
long time2 = end2 -start2;
system.out.println("用string=string+拼接字串的時間"+time2);
long start3 = system.currenttimemillis();
string s3 = new string("hello");
for (long i = 0; i < n; i++)
long end3 = system.currenttimemillis();
long time3 = end3 -start3;
system.out.println("用string.concat拼接字串的時間"+time3);
long start4 = system.currenttimemillis();
stringbuffer s4 = new stringbuffer("hello");
for (long i = 0; i < n; i++)
long end4 = system.currenttimemillis();
long time4 = end4 -start4;
long start5 = system.currenttimemillis();
stringbuilder s5 = new stringbuilder("hello");
for (long i = 0; i < n; i++)
long end5 = system.currenttimemillis();
long time5 = end5 -start5;
system.out.println("end..."); }
}
貼出一組檢測資料如下:
用string+=拼接字串的時間27468
用string=string+拼接字串的時間25813
用string.concat拼接字串的時間12265
幾種拼接字串的效率問題
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幾種拼接字串的效率問題
拼接字串,大致有3個class可以用,他們是string,stringbuffer,stringbuilder,stringbuilder是1.5中來代替stringbuffer的。檢驗方法如下 public class test long end1 system.currenttimemillis...
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