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

java Ïß³ÌÎÊÌâ - Java / Java SE

½ñÌì×öÁ˸öÏ̵߳ÄСÁÐ×Ó,´úÂëÈçÏÂ
public class Test
{
  private int x; 
  public void foo()
  { 
int current=x;
  x=current+1; 
  }
  public void go()
  {
for(int i=0;i<3;i++)
  {
new Thread(){
public void run(){
foo();
  System.out.println(x);
}
}.start();
  }
  }  
  public static void main(String[] str)
  {
  new Test().go();
  }
}

ÓÐʱ»áÊä³ö
2 3 2
  
ÎҸоõºÜÆæ¹Ö,Ïë²»Ã÷°×ÆäÖеĵÀÀí,°´ÎÒ×Ô¼ºµÄ·ÖÎö,Ó¦¸ÃÊÇÕâÑùµÄ...

µ÷ÓÃgo()·½·¨ºó»áÆô¶¯Èý¸öÏß³Ì,Èý¸öÏ̶߳¼»áµ÷ÓÃfoo()Õâ¸ö·½·¨,foo()Õâ¸ö·½·¨Ö÷Òª¾ÍÊǸıä³ÉÔ±±äÁ¿xµÄÖµ,È»ºó´òÓ¡³öxµÄÖµ,ÏÔÈ»,ÕâÈý¸öÏß³ÌÊÇÒì²½µÄ,µ«ÊÇËüÃÇ·ÃÎʵÄx¶¼ÊÇͬһ¸ö³ÉÔ±±äÁ¿Ñ½,¶ÔÓÚ2£¬3£¬2ÕâÑùµÄÊä³ö,°´ÎҵķÖÎöÓ¦¸ÃÊÇÕâÑùµÄ,Ê×ÏÈÔËÐеÄÏß³Ìʹx¼Ó1ºó¾Í×èÈûÁË,È»ºóµÚ¶þ¸öÏß³ÌÔËÐÐʱ¿´µ½xÒѾ­µÈÓÚ1Á˾ÍÔÙ¼ÓÒ»µÈÓÚ2,È»ºóÆäÖÐÒ»¸ö×èÈû,ÁíÒ»¸ö´òÓ¡,ÒòΪ´òÓ¡µÄ¶¼ÊÇͬһ¸ö³ÉÔ±±äÁ¿ËùÒÔÓ¦¸ÃÊÇÐ޸ĺóµÄÖµ2ûʲôÎÊÌâ,È»ºóµÚÈý¸öÏß³ÌÓָıäxµÄÖµ²¢´òÓ¡³ö3(µÚÈý¸öÏß³ÌÖ´ÐÐÊ±Ç°Ãæ×èÈûµÄÄǸöÏß³ÌÓ¦¸Ã»¹ÔÚ×èÈû²»È»Ôõô»á´òÓ¡3),È»ºó×èÈûµÄÄǸöÏß³ÌÔËÐÐ,°´Àí˵ÕâʱËüÒª´òÓ¡µÄxÒѾ­±»µÚÈý¸öÏß³ÌÐÞ¸ÄÁ˳É3ÁË,Ϊʲô»¹Êä³ö2.ÎÒÒ²¿¼Âǵ½ÁË¿ÉÄÜ·ÃÎʵÄÊDz»Í¬ÄÚ´æÇøµÄ±äÁ¿Öµ,µ«ÔÚxǰ¼ÓÉÏÁË volatile ҲûÓÃѽ

Ê®·ÖÀ§»ó,Çë´ó¼Ò°ïÃ


Ïà¹ØÎÊ´ð£º

¹ØÓÚAJAXºÍJSPµÄһЩСÎÊÌâ¡« - Java / Web ¿ª·¢

ÎÒJSPµÄÒ³ÃæÊÇ£º
<%@ page language="java" contentType="text/html; charset=gb2312"
  %>
<script>
function Save(){
xmlHttp=GetXmlHttpObject()
if(xmlHttp==nul ......

tomcat»·¾³ÏÂjsp±àÒë´íÎó£¬Çó½â£¡ - Java / Web ¿ª·¢

org.apache.jasper.JasperException: Unable to compile class for JSP: 
An error occurred at line: 52 in the jsp file: /vip_info.jsp
ÕË cannot be resolved
49: <table border="1& ......

java´òÓ¡ - Java / Java EE

ÓÐË­ÓÃjava×ö¹ý´òÓ¡·¢Æ±µÄ³ÌÐò£¬¸Ð¾õÕâ·½Ãæ²»ÊǺܺÿØÖÆ£¬Ï£Íû¸øµã½¨Ò飬×îºÃÄܸø³ö´úÂë
¼òµ¥µã¾Íµ÷ÓÃwindow.print()
ÄãÒ²¿ÉÒÔ°ÑÏÂÃæ´úÂë·Åµ½ÄãJSPÖÐ:
<html>
 <head>
  <title> ......

jspÐÂÊÖ,Çë½Ì¸÷λ? - Java / Web ¿ª·¢

³ÌÐòÈçÏÂ:
<%@ page contentType="text/html; charset=GBK" %>
<%@ page language="java" %>
<%@ page import="com.mysql.jdbc.Driver" %>
<%@ page import ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ