有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: x;8A!8w
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CountBean.java t({W
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/* xo7Kn+ Kl
* CountData.java Kq;8=xP[
* jbS\vyG
* Created on 2007年1月1日, 下午4:44 U
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* 5) pj]S!]-
* To change this template, choose Tools | Options and locate the template under A}3=561F?5
* the Source Creation and Management node. Right-click the template and choose m>MB7,C;N
* Open. You can then make changes to the template in the Source Editor. ,uSQNre\j
*/ ]hFW73FV
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package com.tot.count; 7G/1VeVjB
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/** IX>d`O61*g
* % a@>_
* @author ):b$xNn
*/ 5'X ]k@m_
public class CountBean { mqSQL}vR
private String countType; 5Hw~2 ?a,
int countId; Q+W1lv8R
/** Creates a new instance of CountData */ wfq7ob4^
public CountBean() {} %)0*&a 4
public void setCountType(String countTypes){ O8j_0
this.countType=countTypes; nv~%#|v_W
} fvdU`*|n)
public void setCountId(int countIds){
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this.countId=countIds; br":y>=,
} WRrd'{sB
public String getCountType(){ 'U\<IL#U
return countType; b"#WxgaF
} T<55a6NoK
public int getCountId(){ X;"Sx#U
return countId; 'gTb A?+@5
} ^]W<X"H+Z
} !>zo_fP
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CountCache.java TwVlg;
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/* M>i9 i-dU
* CountCache.java T`;%TO*Y
* :"xzj<(
* Created on 2007年1月1日, 下午5:01 =1 Oj*x@*4
* #w\~&0
* To change this template, choose Tools | Options and locate the template under O4^8jK}
* the Source Creation and Management node. Right-click the template and choose +KvU$9Ad>
* Open. You can then make changes to the template in the Source Editor. Od5JG .]
*/ /M3Y~l$
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package com.tot.count; S=e{MI
import java.util.*; q(.:9A*0
/** e0T34x'
* /q5v"iX]T
* @author RWgNo#<
*/ m6[0Kws&
public class CountCache { znaUB v_
public static LinkedList list=new LinkedList(); .[3Z1v,
/** Creates a new instance of CountCache */ C86J
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public CountCache() {} H=Y{rq @
public static void add(CountBean cb){ lJis~JLd`
if(cb!=null){ _PlKhv}
list.add(cb); 2VE9}%i
} ?Vf o+a,
} +E.GLn2/
} b7wvaRe.
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CountControl.java i* NH'o/
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/* "vyNxZE
* CountThread.java Ko&>C_N
* W^]3XJP
* Created on 2007年1月1日, 下午4:57 #~l(]h@
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* ,Qnd3[2[
* To change this template, choose Tools | Options and locate the template under 7|[mz> "d
* the Source Creation and Management node. Right-click the template and choose @ vrV*!
* Open. You can then make changes to the template in the Source Editor. li 6%)
*/ |>JS!NM
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package com.tot.count; nY`RRC
import tot.db.DBUtils; .P MZX%*v
import java.sql.*; !Y\D?rKZ
/** ~ ArP9
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* W>p-u6u%E|
* @author 5wh|=**/
*/ ~(IB0=A{v
public class CountControl{ Hqn#yInA7~
private static long lastExecuteTime=0;//上次更新时间 -cSP_1
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 FTQ%JTgT
/** Creates a new instance of CountThread */ v>-VlQ
public CountControl() {} qh2ON>e;
public synchronized void executeUpdate(){ .b-f9qc=
Connection conn=null; qAS qscO
PreparedStatement ps=null; ],JEBt
try{ 7e#?e+5+A
conn = DBUtils.getConnection(); ,;Hu=;
conn.setAutoCommit(false); ]5$eAYq
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !H irhDN
for(int i=0;i<CountCache.list.size();i++){ v(-{=*':
CountBean cb=(CountBean)CountCache.list.getFirst(); q"<ac qK
CountCache.list.removeFirst(); z3K6%rb-
ps.setInt(1, cb.getCountId()); >ey\jDr#O
ps.executeUpdate();⑴ 'b#0t#|TM
//ps.addBatch();⑵ ( 2n>A D_
} S!G(a"<W
//int [] counts = ps.executeBatch();⑶ ]):<ZsT
conn.commit(); YJ;j x0
}catch(Exception e){ '
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e.printStackTrace(); KOp162X>r
} finally{ D[mSmpjE6&
try{ ~D5\O6mU-
if(ps!=null) { I>[RqG
ps.clearParameters(); K,boVFs
ps.close(); 2GWMlI
ps=null; u
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} bVL9vNK
}catch(SQLException e){} {FIXc^m'
DBUtils.closeConnection(conn); u#V5?i
} A%D7bQ
} ALNc'MW!
public long getLast(){ lI-L`
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return lastExecuteTime; O km{Xx
} 7A\~)U@
public void run(){ %9M~f*
long now = System.currentTimeMillis(); T:IW%?M
if ((now - lastExecuteTime) > executeSep) { YR>B_,Gl
//System.out.print("lastExecuteTime:"+lastExecuteTime); z[cyA.
//System.out.print(" now:"+now+"\n"); @:U+9[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 'C:>UlzLy
lastExecuteTime=now; p"FW&Q=PN
executeUpdate(); h|h>u
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} )Jk0v_ X
else{ :L1dyVA{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); "ajjJ"x A
} eOXHQjuj
} {iv<w8CU)
} Gu'rUo3Do
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 5o6>T!
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类写好了,下面是在JSP中如下调用。 lNL6M%e$Q
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<% =Uj-^qcE
CountBean cb=new CountBean(); u6MzRC
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); g-e#!(
CountCache.add(cb); VH(S=G5Yb
out.print(CountCache.list.size()+"<br>"); QR
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CountControl c=new CountControl(); 1XnZy5fEo
c.run(); aS pWsT
out.print(CountCache.list.size()+"<br>"); qWx][D"
%>