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: Z*h ;e;
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CountBean.java n\*JaY
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/* o]p#%B?mZ
* CountData.java w#<^RKk
* Rd vn)K
* Created on 2007年1月1日, 下午4:44 1 Xa+%n9
* wVQdUtmk
* To change this template, choose Tools | Options and locate the template under ,$PFI(Whk
* the Source Creation and Management node. Right-click the template and choose x i.IRAZX
* Open. You can then make changes to the template in the Source Editor. a G@nErdW
*/ W7W3DBKtSm
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package com.tot.count; +0U#.|?
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/** /Bm#`?(ia
* :F9q>
* @author qdO[d|d
*/ e|~C?Ow'J
public class CountBean { QK'`=MU
private String countType; ennR@pg
int countId; ?Oqzd$-
/** Creates a new instance of CountData */ V 1*Ad
public CountBean() {} 44Q9 *."
public void setCountType(String countTypes){ U~CdU
this.countType=countTypes; Y.(v{l
} Q;Q%SI`yT
public void setCountId(int countIds){ yz8-&4YRNd
this.countId=countIds; PM8Ks?P#u
} }D Z)W0RDe
public String getCountType(){ ^pN 5NwC5
return countType; OH0S2?,{>
} @kz!{g]Sn
public int getCountId(){ \w3%[+c
return countId; =hPG_4#
} 5^b i
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} [u7 vY@
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CountCache.java B%2L1T=
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/* T
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* CountCache.java CJv>/#$/F
* xM%`KP.8X
* Created on 2007年1月1日, 下午5:01 y&y/cML?
* Rnzqw,q
* To change this template, choose Tools | Options and locate the template under B( 8mH
* the Source Creation and Management node. Right-click the template and choose UKOFT6|
* Open. You can then make changes to the template in the Source Editor. qP&byEs"
*/ 5St`@
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package com.tot.count; )`mbf|,&t{
import java.util.*; {:,_A
/** _Q)d+Fl
* |.Em_*VG
* @author Z@}sCZ=#A
*/ %v_IX2'
public class CountCache { G5Je{N8W
public static LinkedList list=new LinkedList(); sRi?]9JIl
/** Creates a new instance of CountCache */ _O"L1Let
public CountCache() {} C1KfXC*|L
public static void add(CountBean cb){ B>sCP"/uV
if(cb!=null){ 8W;xi:CC
list.add(cb); sr;:Dvx~
} Y~:}l9Qs
} sw [oQ!f
} 9LH=3Qt
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CountControl.java 1B6C<cL:sU
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/* d3Y(SPO
* CountThread.java .N/GfR`0/<
* |O57N'/
* Created on 2007年1月1日, 下午4:57 R$Zv0a&
* |MR%{ZC^i
* To change this template, choose Tools | Options and locate the template under O%fUm0O d
* the Source Creation and Management node. Right-click the template and choose qZXyi'(d
* Open. You can then make changes to the template in the Source Editor. zIP[R):3&U
*/ P`p6J8}4
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package com.tot.count; C%0<1mp
import tot.db.DBUtils; sS-W~u|C
import java.sql.*;
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/** }iD$4\ L
* GhtbQM1[H
* @author K?9WY]Ot
*/ c/b%T
public class CountControl{ ('T4Db
private static long lastExecuteTime=0;//上次更新时间 EbG_43SV
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ri#,ec|J
/** Creates a new instance of CountThread */ &}>|5>cJu
public CountControl() {} ri"?,}(
public synchronized void executeUpdate(){ ==nYe{2
Connection conn=null; wu;7NatHx
PreparedStatement ps=null; +d@v
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try{ qo61O\qm
conn = DBUtils.getConnection(); m~##q}LZ
conn.setAutoCommit(false); I0I_vu
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^OsA+Ea\
for(int i=0;i<CountCache.list.size();i++){ sP9 ^IP
CountBean cb=(CountBean)CountCache.list.getFirst();
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CountCache.list.removeFirst(); #D=
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ps.setInt(1, cb.getCountId()); EfFj!)fz
ps.executeUpdate();⑴ F# jCEq
//ps.addBatch();⑵ A
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} Jz=;mrW
//int [] counts = ps.executeBatch();⑶ =*{K@p_
conn.commit(); N
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}catch(Exception e){ BHF{-z
e.printStackTrace(); M_qP!+Y
} finally{ =>HIF#jU
try{ o,g6JTh
if(ps!=null) { issT{&T
ps.clearParameters(); }/_('q@s\
ps.close(); =ZCH1J5"
ps=null; sVE>=0TVP
} nsZDZ/jx
}catch(SQLException e){} 8dr0 DF$c
DBUtils.closeConnection(conn); P=f<#l"v
} F"-S~I7'L
} Lv
public long getLast(){ 'Y hA
return lastExecuteTime; $/4Wod*l
} h |s*i
public void run(){ -$AjD?;
long now = System.currentTimeMillis(); 0\V\qAk
if ((now - lastExecuteTime) > executeSep) { DfAiL(
//System.out.print("lastExecuteTime:"+lastExecuteTime); )o05Vda
//System.out.print(" now:"+now+"\n"); (xucZ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &W&7bZ$;
lastExecuteTime=now; K.:6YXVs<
executeUpdate(); ;[?J5X,
} |hu"5*
else{ [P.@1mV
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} db{NKwpj'
} j%6|:o3G(
} F6RyOUma
//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 r0~ 7v1rG
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类写好了,下面是在JSP中如下调用。 B=Xnv*e
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<% /IGrp.}
CountBean cb=new CountBean(); A>qd2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); RA*_&Ll&!C
CountCache.add(cb); M3hy5j(b
out.print(CountCache.list.size()+"<br>"); ?whRlh
CountControl c=new CountControl(); 3c1o,2
c.run(); d[~au=b
out.print(CountCache.list.size()+"<br>"); ^JYF1
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