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: j!l(ReGb
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CountBean.java +q;^8d>
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/* h
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* CountData.java B.o&%5dG
* a)e2WgVB/E
* Created on 2007年1月1日, 下午4:44 Z,z^[Jz
* ]KmYPrCl0
* To change this template, choose Tools | Options and locate the template under B4?P"|
* the Source Creation and Management node. Right-click the template and choose K"D9. %7
* Open. You can then make changes to the template in the Source Editor. F=#Wfl-o
*/ bF.Aj8ZQ
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package com.tot.count; C,E 5/XW
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/** >HDK<1 >
* ?s//a_nL*
* @author -;v:.
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*/ Ez)Go6Q
public class CountBean { 8447hb?W$
private String countType; @RC_Ie=#)
int countId; q/Q*1
/** Creates a new instance of CountData */ e:#\Oh
public CountBean() {} 'oTF$3n
public void setCountType(String countTypes){ ? DPL7
this.countType=countTypes; O;w';}At
} ^l9S5
{
public void setCountId(int countIds){ <MYD`,$yu
this.countId=countIds; B\6\QQ;rUo
} hE;
public String getCountType(){ pJmn;XbME
return countType; !@Ox%vK
} B`vV[w?
public int getCountId(){ tNjrd}8s
return countId; 6l4l74
} cj[y]2{1h
} \oi=fu=}*
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CountCache.java <X: 9y
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/* h:|aQJG5
* CountCache.java ZjzQv)gZ
* "m!Cl-+u
* Created on 2007年1月1日, 下午5:01 z:w7e0
* "Kqe4$
* To change this template, choose Tools | Options and locate the template under Nz m
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* the Source Creation and Management node. Right-click the template and choose mGIS[_dcs
* Open. You can then make changes to the template in the Source Editor. G B15
*/ xd*kNY
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package com.tot.count; EfOJ%Xr[,l
import java.util.*; 1&dWt_\
/** m^wYRA.
* @=$;^}JS|
* @author VL\6U05Z
*/ Z@1rs#
public class CountCache { $zJ.4NA
public static LinkedList list=new LinkedList(); )msqt!Ev
/** Creates a new instance of CountCache */ :5ji.g* 0
public CountCache() {} Q@2Smtu~c
public static void add(CountBean cb){ x{=ty*E
if(cb!=null){ us/x.qPy2
list.add(cb); n04Zji(F@
} 7y:J@fh<
} 3N;X|pa
} _ W$4Qn+f
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CountControl.java (mv8_~F0
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/* lO:[^l?F
* CountThread.java /Qbt
* n84*[d}t
* Created on 2007年1月1日, 下午4:57 #SO9e.yhI
* <h(tW
* To change this template, choose Tools | Options and locate the template under (|S e+Y#e,
* the Source Creation and Management node. Right-click the template and choose y$!~</=b
* Open. You can then make changes to the template in the Source Editor. 8NpQ"0X
*/ P!:D2zSH_
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package com.tot.count; 'peFT[1>(
import tot.db.DBUtils; Yk:\oM
import java.sql.*; 4\t9(_
/** ZMbv1*Vt
* 9= :!XkT.
* @author v-OaH81&R
*/ `a]
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public class CountControl{ Zd042
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private static long lastExecuteTime=0;//上次更新时间 MwiT1sB~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 75%!R
/** Creates a new instance of CountThread */ gg933TLu(Q
public CountControl() {} xmbkn}@A
public synchronized void executeUpdate(){ Tc{r}y[)
Connection conn=null; R`Q9|yF\
PreparedStatement ps=null; |06G)r&
try{ k
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conn = DBUtils.getConnection(); A!SHt7ysJ
conn.setAutoCommit(false); p=T]%k*^h#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [}.OlR3)
for(int i=0;i<CountCache.list.size();i++){ |XPT2eQ{
CountBean cb=(CountBean)CountCache.list.getFirst(); QH;1*
CountCache.list.removeFirst(); ;|66AIwDe
ps.setInt(1, cb.getCountId()); 68d(6?OgW
ps.executeUpdate();⑴ \!`*F:7]-
//ps.addBatch();⑵ gJ :Z7b
} jytfGE:
//int [] counts = ps.executeBatch();⑶ ZfS-W&6Z
conn.commit(); iGM-#{5
}catch(Exception e){ 6:@tHUm
e.printStackTrace(); uS3J^=>@(a
} finally{ [@Y?'={qE
try{ !RAyUfS
if(ps!=null) { p.)G ],
ps.clearParameters(); _.zW[;84b
ps.close(); '\P6NszY~
ps=null; VDBP]LRF
} cSQvP.
}catch(SQLException e){} ji:JLvf]%
DBUtils.closeConnection(conn); >{V]q*[/;Q
} m;k' j@:
} UfXqcyY(
public long getLast(){ @32JMS<
return lastExecuteTime; yPKeatH]
} v:eVK!O
public void run(){ L=?Yc*vg
long now = System.currentTimeMillis(); }m(u oT~
if ((now - lastExecuteTime) > executeSep) { 0OP6VZ\
//System.out.print("lastExecuteTime:"+lastExecuteTime); t\S}eoc
//System.out.print(" now:"+now+"\n"); QXniWJJ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [.;VCk)0x
lastExecuteTime=now; EX=Q(} 9F<
executeUpdate(); u9_ Fjm}&
} UJ2Tj+
else{ g#W )EXUR
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); yS %J$o&
} wYPJji
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} O$<kWSC
} BNnGtVAbZ
//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 R=xT \i{4h
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类写好了,下面是在JSP中如下调用。 ==~X8k|{E
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<% gM '_1zs
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CountBean cb=new CountBean(); ^F/N-!}q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ['Hl$2 j
CountCache.add(cb); D`V03}\-
out.print(CountCache.list.size()+"<br>"); \GEFhM4)
CountControl c=new CountControl(); "o+<
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c.run(); I5
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out.print(CountCache.list.size()+"<br>"); 9m/v^
%>