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: o@gceZuk
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CountBean.java W7A!QS
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/* d6*84'|!
* CountData.java 4G I3|{
* !HU$V9C
* Created on 2007年1月1日, 下午4:44 Wap4:wT
* wbF`wi?
* To change this template, choose Tools | Options and locate the template under X<IW5*
* the Source Creation and Management node. Right-click the template and choose v@Eb[7Kq/1
* Open. You can then make changes to the template in the Source Editor. '.z7)n
*/ R98YGW_
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package com.tot.count; b-8@_@f|g
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/** 0cKsGDm
* f_O|
* @author T8\@CV!
*/ ]Xa]a}[uE
public class CountBean { Uv[a
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private String countType; j;uUM6
int countId; lz>00B<Z
/** Creates a new instance of CountData */ 7r?,wM
public CountBean() {} w^8Q~3|7
public void setCountType(String countTypes){ aNKw.S>
this.countType=countTypes; X%s5D&gr
} }iDRlE,
public void setCountId(int countIds){ SaGI4O_\s
this.countId=countIds; qspGNu
} A@|Z^T:
public String getCountType(){ *A!M0TK?i,
return countType; V0m1>{
} KO8vUR*2R
public int getCountId(){ )|v du
return countId; V^FM-bg%9
} cHr]{@7Cs
} )MI w/
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CountCache.java h(nE)j
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/* Y<POdbg
* CountCache.java 2u_=i$xW
* An(gHi;1$
* Created on 2007年1月1日, 下午5:01 `2U,#nZ 4
* o/,%rA4
* To change this template, choose Tools | Options and locate the template under jo"+_)]
* the Source Creation and Management node. Right-click the template and choose z|AknEE,
* Open. You can then make changes to the template in the Source Editor. $#e}9g.
*/ M.5F|7
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package com.tot.count; Ap\]v2G
import java.util.*; !^L}LtqHI
/** % O%;\t
* </<z7V,{
* @author NY?iuWa*g
*/ r{yIF~k@
public class CountCache { ~qb?#IY]`
public static LinkedList list=new LinkedList(); >@4Ds"Ye"O
/** Creates a new instance of CountCache */ #F
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public CountCache() {} PTpCiiA@
public static void add(CountBean cb){ |'i ?o
if(cb!=null){ cQh{z8Bf?<
list.add(cb); jj `0w@
} b N>Ar
} jkuNafp}
} $a\X(okx
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CountControl.java h;K9}w
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/* &U.y):
* CountThread.java 6x;"T+BSSS
* %u|Qh/?7
* Created on 2007年1月1日, 下午4:57 _["97>q
* K1<l/
s
* To change this template, choose Tools | Options and locate the template under Ej VB\6,
* the Source Creation and Management node. Right-click the template and choose rUiUv(q
* Open. You can then make changes to the template in the Source Editor. nzYFa J +
*/ AQ.q?'vE)
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package com.tot.count; 9qZ|=r]y'
import tot.db.DBUtils; XnvaT(k7Y
import java.sql.*; x~yd/ R
/** 10/3 -)+
* x2f_>tu2
* @author oU 8o;zk0
*/ Q;1$gImFz
public class CountControl{ R91u6r#
private static long lastExecuteTime=0;//上次更新时间 ~u-`L+G"6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]Otl(\v(h
/** Creates a new instance of CountThread */ 9Bmgz =8
public CountControl() {} =WP}RZ{S
public synchronized void executeUpdate(){ XlNB9\"5
Connection conn=null; z<P#djx
PreparedStatement ps=null; Ix5yQgnB}j
try{ *KV]MdS
conn = DBUtils.getConnection(); *JOv
conn.setAutoCommit(false); 8i"{GGVC
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); EA>$t\z
for(int i=0;i<CountCache.list.size();i++){ I`KN8ll
CountBean cb=(CountBean)CountCache.list.getFirst(); oq<#
CountCache.list.removeFirst(); ^jhHaN]G^
ps.setInt(1, cb.getCountId()); \J\1i=a-=
ps.executeUpdate();⑴ %BHq2~J
//ps.addBatch();⑵ +Q_Gm3^
} uTJ?@^nq
//int [] counts = ps.executeBatch();⑶ IX3U\_I#
conn.commit(); s^v,i
CH{
}catch(Exception e){ %I=J8$B]f
e.printStackTrace(); *'t`;m~
} finally{ `RzM)ILl
try{ 3i$AR
if(ps!=null) { I5"=b}V5
ps.clearParameters(); Rx<pV_|H,
ps.close(); Ua3ERBX{
ps=null; f!Ie
} G`W+m*[U+M
}catch(SQLException e){} =UP)b9*h
DBUtils.closeConnection(conn); dCyQC A[
} q.X-2jjpx:
} @<sP1`1
public long getLast(){ J)[(4R>
return lastExecuteTime; wIiT
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} y@z#Jw<
public void run(){ 6a!X`%N=
long now = System.currentTimeMillis(); dk ?0r
if ((now - lastExecuteTime) > executeSep) { p 5'\< gQ
//System.out.print("lastExecuteTime:"+lastExecuteTime); )G|UB8]
//System.out.print(" now:"+now+"\n"); TP^0`L
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); = @f;s<v/
lastExecuteTime=now; Aws
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executeUpdate(); hv)($;
} *\>2DUu\`
else{ J{ Vl2P?@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 3IxT2@H)
} h 2zCX
} ij),DbWd
} kgu+q\?
//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 Pg36'aTe%j
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类写好了,下面是在JSP中如下调用。 *%e#)sn*
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<% "8I4]'
CountBean cb=new CountBean(); $b$D[4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); YGO@X(ej,
CountCache.add(cb); =EJ"edw]%0
out.print(CountCache.list.size()+"<br>"); )wRD
CountControl c=new CountControl(); v>5F[0gE
c.run(); N@$%0!
out.print(CountCache.list.size()+"<br>"); `4qKQJw
%>