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: ^#mWV
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CountBean.java DpeJx
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/* y N9~/g
* CountData.java MRK=\qjD
* 1gcWw, /
* Created on 2007年1月1日, 下午4:44 6-tIe_5
* zPybPE8
* To change this template, choose Tools | Options and locate the template under HeO&p@
* the Source Creation and Management node. Right-click the template and choose RticGQy&5
* Open. You can then make changes to the template in the Source Editor. 5h^BXX|Y*
*/ K(lSR
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package com.tot.count; AXte&l=M
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/** lMh>eX
* LyNmn.nN
* @author reArXmU<u
*/ ~av#r=x
public class CountBean { jO5R ~O`
private String countType; !OQ5AF$
int countId; 4)k-gKS*
/** Creates a new instance of CountData */ rNo/H<J%+j
public CountBean() {} mSYm18
public void setCountType(String countTypes){ >5Lp;
this.countType=countTypes; `q*p-Ju'
} ~x/ka43
public void setCountId(int countIds){ @#hvQ6u
this.countId=countIds; =M4:nt
} iR./9}Ze
public String getCountType(){ 9W]OtS G
return countType; 53ZbtEwhwr
} L@=$0p41;
public int getCountId(){ #Y3-P
return countId; b=\chCRJJ
} kZ)}tA7j
} WFV'^-4
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CountCache.java xP9h$!
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/* u/S>*E
* CountCache.java w xte
* |[mmEYc
* Created on 2007年1月1日, 下午5:01 <%%)C>l
* Qk>U=]U
* To change this template, choose Tools | Options and locate the template under (`E`xb@E,=
* the Source Creation and Management node. Right-click the template and choose Xx[,n-rA
* Open. You can then make changes to the template in the Source Editor. }2e s"
*/ 5p}j{f
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package com.tot.count; 1L'Q;?&2H,
import java.util.*; 3RGmmX"?G
/** `{h)-Y``
* IQtQf_"e1
* @author {r;_nMfH|[
*/ kRwUR34yc
public class CountCache { hDSf>X_*_G
public static LinkedList list=new LinkedList(); f~Pce||e
/** Creates a new instance of CountCache */ irq{ 21
public CountCache() {} !
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public static void add(CountBean cb){ r,Xyb`
if(cb!=null){ 3imsIBr
list.add(cb); X<C fy
} s !2Iui
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} NyRa.hgZ;
} Hd\oV^>
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CountControl.java UjoA$A!Od;
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/* (7b9irL&cn
* CountThread.java {'h&[f>zcQ
* v&/H6r#E.
* Created on 2007年1月1日, 下午4:57 |?{V-L
* +y'2 h%>h[
* To change this template, choose Tools | Options and locate the template under cAwqIihZ
* the Source Creation and Management node. Right-click the template and choose ,"gPd!HD(
* Open. You can then make changes to the template in the Source Editor. u=W[ S)w
*/ Dqc
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package com.tot.count; 5VOw}{Pt
import tot.db.DBUtils; : -#w
import java.sql.*; uF}dEDB|;
/** S ;rd0+J
* %~M* <pN
* @author ;ZAwf0~
*/ Il*!iX|23<
public class CountControl{ o_mjI:
private static long lastExecuteTime=0;//上次更新时间 <dD!_S6@,
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~@l4T_,k
/** Creates a new instance of CountThread */ bfoTGi
public CountControl() {} uHZ4
@w:
public synchronized void executeUpdate(){ 9@ fSO<
Connection conn=null; CR9wp]-Vd
PreparedStatement ps=null; %PB{jo
try{ P/1YN
conn = DBUtils.getConnection(); snfFRc(RE
conn.setAutoCommit(false); B'(zhjV
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =JfwHFHd#
for(int i=0;i<CountCache.list.size();i++){ 9oGcbD4*
CountBean cb=(CountBean)CountCache.list.getFirst(); ak|
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CountCache.list.removeFirst(); XLaD#J
ps.setInt(1, cb.getCountId()); ~BuBma_
ps.executeUpdate();⑴ F_R\
//ps.addBatch();⑵ &@CUxK
} 4XER7c
//int [] counts = ps.executeBatch();⑶ 1?|"33\03R
conn.commit(); u=v-,Tw
}catch(Exception e){ >FOCdlJ#
e.printStackTrace(); Ot\[Ya''
} finally{ i?(cp["7
try{ Q"{Dijc%
if(ps!=null) { .(cpYKFX
ps.clearParameters(); .$}z</#!
ps.close(); =d ;#Nu-
ps=null; 5rck]L'
} uyk;]EYjHZ
}catch(SQLException e){} y3 N[F
DBUtils.closeConnection(conn); gU|:Y&lFZg
} xcmg3:s
} s6!&4=ZA
public long getLast(){ z{w %pUn}
return lastExecuteTime; G]k[A=dg
} @SxZ>|r-|v
public void run(){ 25vjn 1$sW
long now = System.currentTimeMillis(); (T pnJq
if ((now - lastExecuteTime) > executeSep) { w8Z#]kRv
//System.out.print("lastExecuteTime:"+lastExecuteTime); 8M,o)oH
//System.out.print(" now:"+now+"\n"); Q0jg(=9wP
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; M_%KhK
executeUpdate(); uk$MQv*D
} H3R{+7
else{ l]wLQqoO
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); `Rt w'Uz
} ><"|>(y
} D-C]0Jf3
} B1~`*~@
//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 K*DH_\SPK
=,N"% }
类写好了,下面是在JSP中如下调用。 Ekq(
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<% Pi?G:IF
CountBean cb=new CountBean(); U7n#TPet
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >Q@y8*E\F
CountCache.add(cb); Os>&:{D 4!
out.print(CountCache.list.size()+"<br>"); (Ytr&gh;0
CountControl c=new CountControl(); g7hI9(8+
c.run(); d{NMG)`x\
out.print(CountCache.list.size()+"<br>"); S
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