复制代码 代码如下:

package uv;

public class Bean implements Comparable<Bean> {

String sessionId;

Integer num = 1;

public String getSessionId() {

return sessionId;

}

public void setSessionId(String sessionId) {

this.sessionId = sessionId;

}

public Integer getNum() {

return num;

}

public void setNum(Integer num) {

this.num = num;

}

public Bean(String sessionId) {

this.sessionId = sessionId;

}

public void increase() {

++num;

}

@Override

public int compareTo(Bean o) {

return this.sessionId.compareTo( o.getSessionId());

}

@Override

public String toString() {

return sessionId;

}

public static void main(String[] args) {

System.out.println("b".compareTo("b"));;

}

}