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: YZ0y_it)
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CountBean.java Sh@en\m=#S
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/* %jBI*WzR
* CountData.java '!V5 #J
* (7zdbJX
* Created on 2007年1月1日, 下午4:44 K-<kp!v
* ^Fop/\E
* To change this template, choose Tools | Options and locate the template under GS*Mv{JJ
* the Source Creation and Management node. Right-click the template and choose ,)svSzR
* Open. You can then make changes to the template in the Source Editor. ]QqT.z%B
*/ __mnz``/Y
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package com.tot.count; 7>@g)%",
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/** _x'?igy
* L!>EW0
* @author HxE`"/~.7k
*/ i!nPiac
public class CountBean { Le?yzf
private String countType; +t8{aaV
int countId; pBR9)T\n
/** Creates a new instance of CountData */ dv7IHUFf
public CountBean() {} l<DpcLX
public void setCountType(String countTypes){ ?7eD<|
this.countType=countTypes; ;) c 4
} I
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public void setCountId(int countIds){ ' K\ $B_
this.countId=countIds; d*cAm$
} .[Hv/?L
public String getCountType(){ o6b\
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return countType; f3E%0cg
} >Nho`m(
public int getCountId(){ VV%Q "0\
return countId; 8am/5o
} =rL^^MZp
} ^#0k\f>_
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CountCache.java jmkVolz
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/* WGC'k
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* CountCache.java %~{G*%:
* 3W#f
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* Created on 2007年1月1日, 下午5:01 ^1}Y=!&
* *z3wm-z1&
* To change this template, choose Tools | Options and locate the template under _oU}>5
* the Source Creation and Management node. Right-click the template and choose k6(9Rw8bCk
* Open. You can then make changes to the template in the Source Editor. 4UV6'X)V
*/ S!J wF&EW
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package com.tot.count; ]A.tauSW
import java.util.*; ohW
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/** L2WH-XP=
* 9{(A-
* @author DtRu&>o_6D
*/ s0/[mAY
public class CountCache { zEJZ, <
public static LinkedList list=new LinkedList(); FHv^^u'@
/** Creates a new instance of CountCache */ P_y8[Y]?
public CountCache() {} "4Bk
public static void add(CountBean cb){ \~4IOu
if(cb!=null){ +#wh`9[wBt
list.add(cb); $p?TE8G
} C%LXGMt
} gQ8FjL6?
} 4r+s"
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CountControl.java F-&=N {+
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/* 7wA.:$
* CountThread.java 5;4bZ3e,0
* (imaL,M-D
* Created on 2007年1月1日, 下午4:57 R{0nk
* 4],*y`& g
* To change this template, choose Tools | Options and locate the template under 6 $*\%
* the Source Creation and Management node. Right-click the template and choose 'U|Tye i?
* Open. You can then make changes to the template in the Source Editor. O&vE 5%x
*/ gd=gc<z YP
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package com.tot.count; D>>?8a
import tot.db.DBUtils; rd\:.
import java.sql.*; iQ7S*s+l5O
/** 56JvF*hP
* G Ch]5\
* @author ,+mH1#-3
*/ by0@G"AE+
public class CountControl{ kbcqUE
private static long lastExecuteTime=0;//上次更新时间 mR|;}u;d
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 +/|;<K5_LI
/** Creates a new instance of CountThread */ %fH&UFby
public CountControl() {} BK/~2u
public synchronized void executeUpdate(){ f?[0I\V[$
Connection conn=null; J6s@}@R1
PreparedStatement ps=null; ZPO+ #,
try{ wx]r{
conn = DBUtils.getConnection(); [.[|rnil
conn.setAutoCommit(false); -,Y[`(q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $bdtiD
for(int i=0;i<CountCache.list.size();i++){ a|5^4 J\%
CountBean cb=(CountBean)CountCache.list.getFirst(); >anq1Kf
CountCache.list.removeFirst(); u.~`/O
ps.setInt(1, cb.getCountId()); O
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ps.executeUpdate();⑴ 4
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//ps.addBatch();⑵ -l2aAK1M
} J 6%CF2
//int [] counts = ps.executeBatch();⑶ Dmq_jt
conn.commit(); "$6 .L^9W
}catch(Exception e){ WNo",Vc
e.printStackTrace(); L?:fyNA3[
} finally{ `rQDX<?
try{ )o[Jxu'
if(ps!=null) { gK
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ps.clearParameters(); =e j'5m($3
ps.close(); _O w]kP='
ps=null; .`;
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} ^{+,j}V_H
}catch(SQLException e){} !L|PDGD
DBUtils.closeConnection(conn); <^v-y)%N:A
} Hp}d m93T
} T^F9A55y
public long getLast(){ LF?MO1!M
return lastExecuteTime; VQe@H8>3
} M"l<::z
public void run(){ wLW[Vur[
long now = System.currentTimeMillis(); 6:$+"@ps
if ((now - lastExecuteTime) > executeSep) { PS\n0
//System.out.print("lastExecuteTime:"+lastExecuteTime); 8Vf]K}d
//System.out.print(" now:"+now+"\n"); 2n3g!M6~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [e.@Yx_}
lastExecuteTime=now; rfwX:R6,g
executeUpdate(); k'b'Ay(<
} TLWU7aj&!
else{ IJ zPWs5W:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >^|(AzS
} AhauNS^"{R
} [/'=M h
} WPXLN'w+
//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 jYJRG<*e
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类写好了,下面是在JSP中如下调用。 1.6Y=Mh=i[
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<% <>I4wqqb
CountBean cb=new CountBean(); k}tTl 2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "H"4]m1Wc
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); iLR^ V!
CountControl c=new CountControl(); PEIf)**0N
c.run(); ,lUr[xzV
out.print(CountCache.list.size()+"<br>"); lQ!)0F
%>