Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

Effective Java Item12

Effective Java 2nd Edition Reading Notes
Item12: Consider Implementing Comparable interface
¿¼ÂÇʵÏÖComparable½Ó¿Ú
 
compareTo·½·¨²¢²»ÊÇjava.lang.ObjectÀඨÒåµÄ·½·¨¡£ËüÊÇComparable½Ó¿ÚÖеÄΨһµÄÒ»¸ö·½·¨¡£ËüºÍObjectÀàµÄequals·½·¨ÀàËÆ£¬Ö»ÊÇËüÔÊÐíÖ¸¶¨×Ô¶¨ÒåµÄ±È½Ï£¬¶ø²»ÊǼòµ¥µÄÏàµÈÐԱȽϣ»²¢ÇÒËüÊÇͨÓõġ£ Ààͨ¹ýʵÏÖComparable½Ó¿ÚÀ´ÉùÃ÷ËüµÄʵÀý¾ßÓÐ˳ÐòµÄ¡£
Èç¹ûÀàʵÏÖÁËComparable½Ó¿Ú£¬ÄÇôÈç¹ûÒ»¸öÊý×éµÄÔªËØÊǸÃÀàµÄʵÀý£¬ÄÇô¿ÉÒÔͨ¹ýʹÓÃArrays.sort()½øÐÐÅÅÐò¡£
package com.googlecode.javatips4u.effectivejava.comparable;
import java.util.Arrays;
public class OrderedArray implements java.lang.Comparable<OrderedArray> {
       private int displayOrder;
       public OrderedArray(int displayOrder) {
              this.displayOrder = displayOrder;
       }
       public int compareTo(OrderedArray o) {
              int result = this.getDisplayOrder() - o.getDisplayOrder();
              if (result == 0) {
                     return 0;
              }
              return result > 0 ? 1 : -1;
       }
       public int getDisplayOrder() {
              return displayOrder;
       }
       /**
        * @param args
        */
     


Ïà¹ØÎĵµ£º

JAVA»·¾³±äÁ¿ÉèÖÃ

¾ÙÀý×Ó˵Ã÷Ò»ÇС£
JAVA_HOME£º C:\j2sdk1.4.2_13
 
Path£º         C:\j2sdk1.4.2_13\bin;
Classpath£º.;JAVA_HOME\lib\tools.jar ; JAVA_HOME\lib\dt.jar;
                 &n ......

javaʱ¼ä¶¯Ì¬ÏÔʾ Á½ÖÖ·½·¨

ʱ¼ä¶¯Ì¬ÏÔʾ
1.·½·¨Ò» ÓÃTimerTask
ÀûÓÃjava.util.TimerºÍjava.util.TimerTaskÀ´×ö¶¯Ì¬¸üУ¬±Ï¾¹Ã¿´Î¸üпÉÒÔ¿´×÷ÊǼÆÊ±1Ãë·¢ÉúÒ»´Î¡£
´úÂëÈçÏ£º
import java.awt.Dimension;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.Timer;
import java.util ......

Java ÒÀÀµ×¢É乿·¶£¨JSR

JCP SE/EE Ö´ÐÐίԱ»á
Õýʽ½ÓÊÜÁË
JSR 330
—— Dependency Injection for Java¡£¸Ã¹æ·¶ÓÚ ½ñÄê 5 Ô 9 ÈÕ
ÓÉ Google µÄ Bob Lee ÒÔ¼° SpringSource µÄ Rod Johnson ×÷Ϊ¹æ·¶Áìµ¼Ìá½»¸ø JCP£¬ÏÖÔÚÒѾ­Õýʽ·¢²¼£¬²»µÃ²»¸Ð̾¸Ã¹æ·¶±ê×¼»¯¹ý³ÌÖ®¿ì¡£ÔÚ ×îÖÕͶƱ½á¹ûÖÐ
£¬14 Ʊͨ¹ý£¬1 ƱδͶ£¬1 Ʊ·´¶Ô¡£
J ......

Java֮staticѧϰ

¶ÔÓÚѧϰstaticÎÒÃÇÏÈÀ´¿´Á½¸öÀý×Ó£º
//Example 1 Tst.java£¬no main() method
package com.blogchina.qb2049;
public class Tst
{
static { System.out.println("111111"); }
}
ÔËÐнá¹ûΪ: 111111
Exception in thread "main" java.lang.NoSuchMethodError: main
ͬÑùµÄµÀÀí¿´µÚ¶þ ......

Jconsole ºÍ jps ÎÞ·¨ÏÔʾ±¾µØ Java ½ø³ÌÁбí

ǰһÕóÔÚ¹«Ë¾ÀïʹÓà jconsle ʱһÇÐÕý³££¬È»¶øÔÚ¼ÒÖеĻúÆ÷ÉÏÈ´³öÏÖÁ˱êÌâËùʾµÄÎÊÌ⣺
jconsole ºÍ jps ÎÞ·¨ÏÔʾ±¾µØ Java ½ø³ÌÁÐ±í¡£
µ±Ê±Ö±½ÓÀûÓà -Dcom.sun.management.jmxremote.port=port Æô¶¯Ä¿±ê java ½ø³Ì£¬²¢ÔÚ jconsole ÖÐͨ¹ý localhost:port ·½Ê½³É¹¦Á¬½ÓÉÏÄ¿±ê java ½ø³Ì¡£ÓÐÁËÕâ¸ö work around Ö®ºó£¬¶ÔÕ ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ