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: :'91qA%Wr
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CountBean.java '$YB
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/* rdhK&5x*
* CountData.java =dx!R ,Bw
* _Db=I3.HJ
* Created on 2007年1月1日, 下午4:44 CL.JalR`b
* <vJPKQ`=:
* To change this template, choose Tools | Options and locate the template under K*&M:u6E
* the Source Creation and Management node. Right-click the template and choose Py$Q]s?\1
* Open. You can then make changes to the template in the Source Editor. {YC!pDG
*/ VR ^qwS/
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package com.tot.count; mE'y$5ZxY
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/** -G e5gQ=
* rZ2X$FO@
* @author FRd!UqMXY
*/ (+68s9XS7
public class CountBean { px %xoY
private String countType; 26PUO$&b.
int countId; X1&Ug^
/** Creates a new instance of CountData */ Qz\yoI8JA,
public CountBean() {} 8]skAh
public void setCountType(String countTypes){ [bk2RaX:i
this.countType=countTypes; 3XF.$=@
} Tm(XM<
public void setCountId(int countIds){ S-}MS"
this.countId=countIds; fOJ0#^Z
} zs
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public String getCountType(){ N-`Vb0;N
return countType; 8@]*X,umc
} :,gnOfV=
public int getCountId(){ 6w(Mb~[n
return countId; +KgoL a
} ZUP\)[~
} 2+zE|I.
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CountCache.java :Rv?>I j
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/* vw5f.8T;w
* CountCache.java Z:DEET!c'k
* o`5p
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* Created on 2007年1月1日, 下午5:01 ph{p[QI:{X
* /_<`#?5T(
* To change this template, choose Tools | Options and locate the template under 3[I; 3=O
* the Source Creation and Management node. Right-click the template and choose _G%]d$2f`
* Open. You can then make changes to the template in the Source Editor. EBlfwFd
*/ !>fYD8Ft,
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package com.tot.count; LOQoi8j
import java.util.*; c.-h'1
/** j[l6&eX
* xFxl9oM."
* @author Mx{VN
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*/ o|Cq#JFG
public class CountCache {
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public static LinkedList list=new LinkedList(); =sy>_
/** Creates a new instance of CountCache */ 56gpAc
public CountCache() {} U"$Q$ OFs
public static void add(CountBean cb){ .w2QiJ
if(cb!=null){ Go~bQ2*'(/
list.add(cb); ;, P-2\V/
} arJ4^ d
} &7z79#1NS
} D FDC'E
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CountControl.java |T?wM/
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/* ,K9\;{C
* CountThread.java ?&;d#z*4
* KilgeN:
* Created on 2007年1月1日, 下午4:57 XndGe=O
* 8|^dM$
* To change this template, choose Tools | Options and locate the template under b ~DtaGh
* the Source Creation and Management node. Right-click the template and choose [
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* Open. You can then make changes to the template in the Source Editor. 0^'A^
*/ u.;zz'|
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package com.tot.count; -c-af%xD
import tot.db.DBUtils; . K`OEdr<
import java.sql.*; 2VmQ%y6e"
/**
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* V.zKjoky@
* @author r=GF*i[3
*/ iEx.BQ+
public class CountControl{ r@C2zF7
private static long lastExecuteTime=0;//上次更新时间 gXr"],OM;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 XMhDx
/** Creates a new instance of CountThread */ KHwzQ<Z3
public CountControl() {} i9Fg
public synchronized void executeUpdate(){ 9$,x^Qx
Connection conn=null; *9:oTN
PreparedStatement ps=null; z_%G{H+:l
try{ \zj _6Os
conn = DBUtils.getConnection(); d:/8P985
conn.setAutoCommit(false); <p@c%e,_
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *r!f! eA:
for(int i=0;i<CountCache.list.size();i++){ 5dffFe
CountBean cb=(CountBean)CountCache.list.getFirst(); H I/]s^aL
CountCache.list.removeFirst(); >55c{|"@L
ps.setInt(1, cb.getCountId()); tX;00g;U.
ps.executeUpdate();⑴ )"?6Es SF
//ps.addBatch();⑵ p7(Pymkd
} IOA"O9;
//int [] counts = ps.executeBatch();⑶ Zgp]s+%E
conn.commit(); >Gbj1>C}
}catch(Exception e){ <hi@$.u_Q^
e.printStackTrace(); TR!^wB<F
} finally{ S,T?(lSl
try{ b *IJ +
if(ps!=null) { B{|g+c%
ps.clearParameters(); /CpUq;^
ps.close(); 3/IQ]8g"
ps=null; $ tf;\R
} 4 -)'a} O
}catch(SQLException e){} T1zft#1~
DBUtils.closeConnection(conn); ,4y'(DA
} N;,?k.vU
} 97:1L4w.(
public long getLast(){ .0]4@'
return lastExecuteTime; wUzQ`h2
} "%~\kJ(G
public void run(){ v +-f
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long now = System.currentTimeMillis(); U$a Eby.
if ((now - lastExecuteTime) > executeSep) { SsA;T5:6
//System.out.print("lastExecuteTime:"+lastExecuteTime); G yZYP\'S+
//System.out.print(" now:"+now+"\n"); x_1JQDE
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }*Qd]\fy
lastExecuteTime=now; tq=1C=h
executeUpdate(); dDH+`;$.
} F\1nc"K/(
else{ f])?Gw
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1lyJ;6i6L
} ^q6H
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} OJE<2:K
} :PtpIVAosg
//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 QFoZv+|
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类写好了,下面是在JSP中如下调用。 XfA3Ez,}
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<% 8D]:>[|E
CountBean cb=new CountBean(); g+/%r91hZ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !-
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CountCache.add(cb); 3WyK!@{
out.print(CountCache.list.size()+"<br>"); j&E4|g (
CountControl c=new CountControl(); 5@c,iU-L
c.run(); ,2S
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out.print(CountCache.list.size()+"<br>"); /2^cty.BXw
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