import java.sql.Time;

public class Javatest72 {
    /**
     * String和StringBuffer效能對比
     * 練習1：寫程式碼測試字串拼接的效能，比如拼接10萬次
     * 輸出結果：
     * String拼接時間：14863.0
     * StringBuffer拼接時間：0.0
     */
    public static void main(String[] args) {
        String s = "abc";
        String s2 = "";
        double
 
 start = System.currentTimeMillis();
        for (int i = 0; i < 100000; i++) {
            s2 += s;
        }
        double end = System.currentTimeMillis();
        System.out.println("String拼接時間：" + (end - start));
        StringBuffer s1 = new StringBuffer("abc");
        StringBuilder s3 = new StringBuilder(""
 
);
        double start1 = System.currentTimeMillis();
        for (int i = 0; i < 100000; i++) {
            s3.append(s1);
        }
        double end1 = System.currentTimeMillis();
        System.out.println("StringBuffer拼接時間：" + (end1 - start1));
    }

}