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: I_/kJ#7vj
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CountBean.java SOPQg?'n=V
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/* T-L;iH~0
* CountData.java std4Nyp
* ZZXQCP6]
* Created on 2007年1月1日, 下午4:44 u teI[Q
* 5lMm8<v
* To change this template, choose Tools | Options and locate the template under |Skxa\MI
* the Source Creation and Management node. Right-click the template and choose zXH CP.Rmg
* Open. You can then make changes to the template in the Source Editor. 38hA guZX
*/ WV'FW)%
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package com.tot.count; k_c8\::p#
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/** 5YG?m{hyn_
* =os%22*
* @author @pKQ}?
*/ T"2D<7frbo
public class CountBean { 1x^(vn#=
private String countType; N?'V,p
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int countId; =O)dHY}
/** Creates a new instance of CountData */ yn[^!GuJ_
public CountBean() {} 27t23@{YL
public void setCountType(String countTypes){ x@I(G "
this.countType=countTypes; 54 Baz
} U0+Hk+
public void setCountId(int countIds){ :(|;J<R%_
this.countId=countIds; &.Jp,Xt)
} l(T CF
public String getCountType(){ EEaf/D/ jt
return countType; 0.~Pzg
} Q`Q%;%t
public int getCountId(){ ^fLePsmd
return countId; CE$c/d[N.
} \V|\u= @H
} OgiElA.
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CountCache.java @}K'Ic
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/* 4*4s{twG
* CountCache.java LsnM5GU7
* HXTBxh
* Created on 2007年1月1日, 下午5:01 /3!KfG
* ,OX(z=i_
* To change this template, choose Tools | Options and locate the template under O;9'0-F ?
* the Source Creation and Management node. Right-click the template and choose Y{TzN%|LV
* Open. You can then make changes to the template in the Source Editor. x?:[:Hf
*/ #ra~Yb-F
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package com.tot.count; %pNK ?M+
import java.util.*; 4|uh&4"*@W
/** #7IM#tc@
* $!L'ZO1_r
* @author 1nb]~{l
*/ + RX{
public class CountCache { P {x`eD0
public static LinkedList list=new LinkedList(); 8.
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/** Creates a new instance of CountCache */ _uuxTNN0x*
public CountCache() {} 4tR:O#($V
public static void add(CountBean cb){ ^[noGjy
if(cb!=null){ _ cK"y2
list.add(cb); `Nn=6[]
} a$p?r3y
} wfQ6J0
} Q#
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CountControl.java r#^/qs(~
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/* 4k5X'&Q
* CountThread.java =EI>@Y"
* TT3GFP
* Created on 2007年1月1日, 下午4:57 eXY*l>B
* l2"{uCcA
* To change this template, choose Tools | Options and locate the template under ufE;rcYE
* the Source Creation and Management node. Right-click the template and choose nqNL[w6{
* Open. You can then make changes to the template in the Source Editor. `LU[+F8<
*/ #Hl0>"k
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package com.tot.count; p< i;@H;:
import tot.db.DBUtils; ezn%*X
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import java.sql.*; G.Z:00x
/** ~Ts^z(v~D2
* 9P;}P!W
* @author e^)+bmh
*/ InnjZ>$
public class CountControl{ 64Gd^.Z
private static long lastExecuteTime=0;//上次更新时间 ~u-DuOZ8
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 (_h<<`@B
/** Creates a new instance of CountThread */ `)Z"||8K
public CountControl() {} e&WlJ
public synchronized void executeUpdate(){ m2 0:{fld
Connection conn=null; ?.tnaE
PreparedStatement ps=null; .{[+d3+,
try{ EXDZehLD<]
conn = DBUtils.getConnection(); t*Hr(|.
conn.setAutoCommit(false); mw2/jA7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 77D>;90>?
for(int i=0;i<CountCache.list.size();i++){ {;uOc{~+
CountBean cb=(CountBean)CountCache.list.getFirst(); M0Y#=u.
CountCache.list.removeFirst(); \1Tu
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ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ hKVj\88
//ps.addBatch();⑵ a"7zz]XO2
} DFDlp
//int [] counts = ps.executeBatch();⑶ nn[OC=cDN
conn.commit(); ZfM DyS$.
}catch(Exception e){ H_w&_h&
e.printStackTrace(); zh8\
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} finally{ F/gA[Y|,gI
try{ .[mI9dc
if(ps!=null) { L@9@3?
ps.clearParameters(); ykAZP[^'
ps.close(); UAleGR`,
ps=null; -rg >y!L
} e_U1}{=t
}catch(SQLException e){} =CBY_
DBUtils.closeConnection(conn); R( 2,1f=d
} i2bkgyzB.
} `Hlv*" w$
public long getLast(){ 8v{0=9,Z
return lastExecuteTime; vs=8x\W
} 'Cr2&
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public void run(){ \%],pZsA ~
long now = System.currentTimeMillis(); m2sf]-?Y
if ((now - lastExecuteTime) > executeSep) { wE*o1.
//System.out.print("lastExecuteTime:"+lastExecuteTime); 'xK ,|U
//System.out.print(" now:"+now+"\n"); MS Qz,nn
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); hYvWD.c}
lastExecuteTime=now; M~h^~:Lk
executeUpdate(); Y8i'=Po%,
} oItEGJ|
else{ @%"+;D
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); z4!Y9
} Nw3K@Ge
} Z'Uc}M'U
} tBB\^xq:
//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 ]h3{MTr/
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类写好了,下面是在JSP中如下调用。 0,{tBo
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<% TyGsSc
CountBean cb=new CountBean(); v%
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); mMt~4(5
CountCache.add(cb); Uo]x6j<
out.print(CountCache.list.size()+"<br>"); 7my7|s[
CountControl c=new CountControl(); _6Z}_SiOl
c.run(); v)c[-:"z
out.print(CountCache.list.size()+"<br>"); c.?+rcnq
%>