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: ICvV}%d
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CountBean.java 0/b
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/* kQ lU.J>^
* CountData.java ](A2,F
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* wWy;dma#
* Created on 2007年1月1日, 下午4:44 Vv45w#w;
* n{FjFlX2=
* To change this template, choose Tools | Options and locate the template under qh:Bc$S
* the Source Creation and Management node. Right-click the template and choose 0]kKF<s
* Open. You can then make changes to the template in the Source Editor. ^J5{quV
*/ iN[x
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package com.tot.count; d<6F'F^w.7
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/** xwf-kwF8^
* O=A2QykV(
* @author d=PX}o^
*/ >%k6k1CZ
public class CountBean { M'PZ{6;
private String countType; mK[Z#obc=
int countId; y
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/** Creates a new instance of CountData */ N-\N\uN
public CountBean() {} qcS.=Cj?)
public void setCountType(String countTypes){ XP:A"WK"
this.countType=countTypes; d )O^(y1r
} S^eem_C
public void setCountId(int countIds){ (-21h0N[V
this.countId=countIds; @kWL "yy,
} +e-F`k
public String getCountType(){ x#J9GP.
return countType; gSz<K.CT
} x9"Cm;H%
public int getCountId(){ HOR8Jwf:
return countId; Yv5H41o"
} X.eOw>.
} V4n~Z+k
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CountCache.java P>VoA
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/* 1f`De`zXzr
* CountCache.java v;x0=I&%
* m2c'r3 UEu
* Created on 2007年1月1日, 下午5:01 BDB*>y7(
* ;=Ma+d#
* To change this template, choose Tools | Options and locate the template under C\EIaLN<
* the Source Creation and Management node. Right-click the template and choose H<(F$7Q!\
* Open. You can then make changes to the template in the Source Editor. 2.D2
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*/ >A$L&8'C
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package com.tot.count; a!9'yc
import java.util.*; }a7d(7
/** (/e&m=~
* gQy%T]
* @author b/M/)o!C
*/ /4G1,T_,
public class CountCache { Ti%MOYNCv
public static LinkedList list=new LinkedList(); D&G6^ME
/** Creates a new instance of CountCache */ E^1yU
public CountCache() {} }QFL
public static void add(CountBean cb){ YThVG0I =
if(cb!=null){
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list.add(cb); sbW+vc
} oY)eN?c
} o,*m,Qc
} /Y#8.sr
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CountControl.java )A8#cY!<
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/* >jW**F
* CountThread.java rNP;53FtZl
* ZcN0:xU
* Created on 2007年1月1日, 下午4:57 C/k#gLF`
* Kh]es,$D
* To change this template, choose Tools | Options and locate the template under #a e@VedM
* the Source Creation and Management node. Right-click the template and choose q+?&w'8
* Open. You can then make changes to the template in the Source Editor. WqeWjI.2
*/ /Q1 b%C
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package com.tot.count; UPhO=G
import tot.db.DBUtils; *k{Llq
import java.sql.*; h`&TDB2
/** Kxsd@^E
* MntmBj-T
* @author SZWNN#w60?
*/ oGcgd$%ZB
public class CountControl{ _Xf1FzF+a
private static long lastExecuteTime=0;//上次更新时间 Y&6jFT_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1)X|?ZD]F
/** Creates a new instance of CountThread */ 7{#p'.nc5
public CountControl() {} b~gq8,Fatb
public synchronized void executeUpdate(){ ynsYU(
Connection conn=null; TGJz[Ny
PreparedStatement ps=null; Wg|6{'a
try{ REh"/d
conn = DBUtils.getConnection(); ;jzJ6~<
conn.setAutoCommit(false); K*@?BE
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 56Wh<i3
for(int i=0;i<CountCache.list.size();i++){ $u<;X^
CountBean cb=(CountBean)CountCache.list.getFirst(); K)'[^V Xh
CountCache.list.removeFirst(); )I%M]K]F
ps.setInt(1, cb.getCountId()); + ~V%R{h
ps.executeUpdate();⑴ T<uX[BO-a
//ps.addBatch();⑵ S Qmn*CW
} {!I`EN]
//int [] counts = ps.executeBatch();⑶ OxJHhF
conn.commit(); o,i_py
}catch(Exception e){ fbApE
e.printStackTrace(); f7&ni#^Ztj
} finally{ GgpE"M?
try{ fzJiW@-T
if(ps!=null) { @/#G2<Vp1
ps.clearParameters(); awzlLI<2p
ps.close(); *d8
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ps=null; ToHx!,tDS
} MV5$e
}catch(SQLException e){} ;~F*2)
DBUtils.closeConnection(conn); Z\0wQ;}
} %DttkrhL
} T!x/^
public long getLast(){ E2zL-ft.
return lastExecuteTime; 4rhHvp
} )
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public void run(){ ug%7}&
long now = System.currentTimeMillis(); nAQ[
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if ((now - lastExecuteTime) > executeSep) { qjRbsD>
//System.out.print("lastExecuteTime:"+lastExecuteTime); M(>74(}]
//System.out.print(" now:"+now+"\n"); JrBPx/?(,;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ub?dfS9$_
lastExecuteTime=now; 5YrzOqg=
executeUpdate(); \(??Ytc<B
} *L<EGFP
else{ f#c}}>V8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6GuTd
} `@y~ JNf!
} TFHYB9vV
} @kSfF[4H
//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 .nY}_&
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类写好了,下面是在JSP中如下调用。 D&fOZVuqZ
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<% 56Lxr{+X
CountBean cb=new CountBean(); !~zn*Hm
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); O
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CountCache.add(cb); LDegJer-v
out.print(CountCache.list.size()+"<br>"); o"qxR'V
CountControl c=new CountControl(); O=K0KOj
c.run(); \>\ERVEd
out.print(CountCache.list.size()+"<br>"); z&9ljQ
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