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: 2./;i>H[u
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CountBean.java ciGJtD&P
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/* Q?/qQ}nNw
* CountData.java jj6yf.r6c
* ch]{=61
* Created on 2007年1月1日, 下午4:44 jH?!\F2)+
* E D^0t
* To change this template, choose Tools | Options and locate the template under aDda&RM
* the Source Creation and Management node. Right-click the template and choose uS7kkzt-x
* Open. You can then make changes to the template in the Source Editor. _(F8}s
*/ ubUVxYD?
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package com.tot.count; qrufnu5cC
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/** VMH^jCFp
* 20cEE>
* @author .JX9(#Uk
*/ DhD^w;f]
public class CountBean { do:IkjU~
private String countType; ?}"39n
int countId; 'wni.E&
/** Creates a new instance of CountData */ h&2l0|8k
public CountBean() {} fs0EbVDF
public void setCountType(String countTypes){ vX|5*T`(
this.countType=countTypes; \gR%PN
} v"-K-AQjB
public void setCountId(int countIds){ <h%I-e6
this.countId=countIds; 0t7vg#v|
} Z7p!YTA
public String getCountType(){ 8\Bb7*
return countType; K/M2L&C
} A\<W x/
public int getCountId(){ I&;9
return countId; AK(x;4
} `k`P;(:
} Y&-%
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CountCache.java n&3}F?
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/* ym_p49
* CountCache.java tmi)LRF
H
* u(i=-PN_<
* Created on 2007年1月1日, 下午5:01 i!EAs`$o`
* {r'+icvLX
* To change this template, choose Tools | Options and locate the template under 5i+cjT2
* the Source Creation and Management node. Right-click the template and choose -tfUkGdx;l
* Open. You can then make changes to the template in the Source Editor. b_^y
Ke^W
*/ 0ZJj5<U
**JBZ \'
package com.tot.count; sO{TGk]*
import java.util.*; f$ 7C 5
/** qHnX)
* xZA.<Yd^r
* @author ?[7KN8$
*/ 1>Q4&1Vn
public class CountCache { Bk[C=< X
public static LinkedList list=new LinkedList(); 0+e
/** Creates a new instance of CountCache */ e,
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public CountCache() {} sLUOs]cj
public static void add(CountBean cb){ +t3o5&
if(cb!=null){ ~*x 2IPiH
list.add(cb); 1!NrndJ I
} }=Ul8
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} .wB'"z8L
} gloJ;dEB
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CountControl.java i` Q&5KL
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/* T^vhhfCUr
* CountThread.java ;GIA`=a%
* w[C*w\A\M
* Created on 2007年1月1日, 下午4:57 E+lr{~
* Jv} &8D
* To change this template, choose Tools | Options and locate the template under 51Vqbtj^
* the Source Creation and Management node. Right-click the template and choose "6
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* Open. You can then make changes to the template in the Source Editor. <w`EU[y_
*/ ;cB3D3fR.
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package com.tot.count; -Aojk8tc
import tot.db.DBUtils; Y&H<8ez
import java.sql.*; +lb&_eD
/** kc(m.k!|f\
* hfw+n<
* @author QiK-|hFj
*/ F?[1m2
public class CountControl{ !o1IpTN
private static long lastExecuteTime=0;//上次更新时间 83 <CDjD
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ c0Pj})-
public CountControl() {} qsQ{`E0
public synchronized void executeUpdate(){ bi^Pk,'
Connection conn=null; ?Yzw]ag.
PreparedStatement ps=null; 4}s'xMT!
try{ OTl9MwW
conn = DBUtils.getConnection(); .>z1BP:(
conn.setAutoCommit(false); YgdQC(ib
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "blq)qo)
for(int i=0;i<CountCache.list.size();i++){ lV$CBS
CountBean cb=(CountBean)CountCache.list.getFirst(); )K$YL='kX
CountCache.list.removeFirst(); ;dPaWS1D
ps.setInt(1, cb.getCountId()); U!NuiKaQ26
ps.executeUpdate();⑴ zXD/hM
//ps.addBatch();⑵ h8X[*Wme
} XwFTAaZ
//int [] counts = ps.executeBatch();⑶ .]s? 01Z
conn.commit(); >]8(3&zd
}catch(Exception e){ s1h|/7gG
e.printStackTrace(); RMiDV^.u`
} finally{ uVKe ?~RC
try{ `S0`3q}L3%
if(ps!=null) { _QEw=*.<
ps.clearParameters(); ;|0P\3
ps.close(); >I/@GX/
ps=null; 4hc[rN,]
} Np%Q-T\
}catch(SQLException e){} bX$1PYX
DBUtils.closeConnection(conn); j1A%LS;c_
} dNhbvzl(
} CAC%lp
public long getLast(){ z~3GgR"1d
return lastExecuteTime; `+rwx
} 5:jme$BI
public void run(){ Arm'0)B>
long now = System.currentTimeMillis(); j#~~_VA~
if ((now - lastExecuteTime) > executeSep) { /Ry%K4$
//System.out.print("lastExecuteTime:"+lastExecuteTime); )z\#
//System.out.print(" now:"+now+"\n"); c BZ,"kp-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Xdx8HB@L
lastExecuteTime=now; \Oq8kJ=
executeUpdate(); *hru);OJr
} g$^-WmX\m
else{ ~TsRUT
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /#
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} wN58uV '
} Hy1$Kvub
} }Nd1'BVf
//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 >}\s-/
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类写好了,下面是在JSP中如下调用。 :L@n(buRN
?_d6;
<% r7oFG!.?
CountBean cb=new CountBean(); }8"
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _dRB=bl"O
CountCache.add(cb); VnVBA-#r|
out.print(CountCache.list.size()+"<br>"); ^3BPOK[*gB
CountControl c=new CountControl(); Jx~H4y=z
c.run(); .|^Gde
out.print(CountCache.list.size()+"<br>"); ,dR.Sacv
%>