?? test.java
字號:
class test
{
public static void foo(int val)
{
String str = new String("Practical ");
for (int i=0; i<val; i++)
str += "Java";
}
public static void bar(int val)
{
StringBuffer str = new StringBuffer("Practical ");
for (int i=0; i<val; i++)
str.append("Java");
}
public static void main(String args[])
{
int val = Integer.parseInt(args[0]);
long start = System.currentTimeMillis();
foo(val);
long end = System.currentTimeMillis();
System.out.println("foo is " + (end-start));
long num = end-start;
start = System.currentTimeMillis();
bar(val);
end = System.currentTimeMillis();
System.out.println("bar is " + (end-start));
num = num/(end-start);
System.out.println("concat is " + num + " times faster");
}
}
?? 快捷鍵說明
復制代碼
Ctrl + C
搜索代碼
Ctrl + F
全屏模式
F11
切換主題
Ctrl + Shift + D
顯示快捷鍵
?
增大字號
Ctrl + =
減小字號
Ctrl + -