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:
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CountBean.java s Z].8.
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/* "ut39si
* CountData.java z7fp#>uw
* Jdj2~pTq
* Created on 2007年1月1日, 下午4:44 I&x=;
* 3YR!Mq$|~
* To change this template, choose Tools | Options and locate the template under 0AL=S$B)
* the Source Creation and Management node. Right-click the template and choose p8Qk'F=h
* Open. You can then make changes to the template in the Source Editor. fHx*e'eA
*/ v dc\R?
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package com.tot.count; %]}
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/** +%h8r5o1
* c(xrP/yOwi
* @author 286jI7 T
*/ ,l\-xSM
public class CountBean { L>Fa^jq5
private String countType; w;4<h8Wn5
int countId; 4V)kx[j
/** Creates a new instance of CountData */ #lL^?|M
public CountBean() {} UGV+/zxIM
public void setCountType(String countTypes){ 8V`WO6*
this.countType=countTypes; W}@c|d $`
} aC8} d
public void setCountId(int countIds){ 65JF`]
this.countId=countIds; V]lLw)
} KQ% GIz x
public String getCountType(){ 8Fz#A.%P
return countType; z]_wjYn Z
} {EB;h\C
public int getCountId(){ s+$ Q}|?u
return countId;
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} ; F"g$_D0
} *&^Pj%DX
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CountCache.java yg<R=$n,Q
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/* 0d)M\lG
* CountCache.java IL#"~D?
* wDal5GJp
* Created on 2007年1月1日, 下午5:01 l[0RgO*S
* k8&;lgO'
* To change this template, choose Tools | Options and locate the template under HdUQCugxx:
* the Source Creation and Management node. Right-click the template and choose P64PPbP
* Open. You can then make changes to the template in the Source Editor. $w`xvX
*/ pP&7rRhw
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package com.tot.count; ;"5&b!=t
import java.util.*; l*(8i ^
/** K_|k3^xx"
* NX*Q F+
* @author %S960
*/ ZB=
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public class CountCache { [Kg+^N%+
public static LinkedList list=new LinkedList(); %}SrL*
/** Creates a new instance of CountCache */ >
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public CountCache() {} ;#W2|'HD
public static void add(CountBean cb){ p_gm3Q
if(cb!=null){ AUG#_HE]k
list.add(cb); c<:-T
} t6"%3#s
} X:"i4i[}{9
} Cn34b_Sbd
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CountControl.java RB7tmJc
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/* MS~(D.@ZS
* CountThread.java Y8~"vuIE5
* V(I8=rVH
* Created on 2007年1月1日, 下午4:57 QOGvC[*`<T
* i+ ?^8#
* To change this template, choose Tools | Options and locate the template under C_}]`[
* the Source Creation and Management node. Right-click the template and choose J5K^^RUR
* Open. You can then make changes to the template in the Source Editor. @1roe
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*/ F]O`3e=!
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package com.tot.count; ?=sDM& '
import tot.db.DBUtils; J/y83@
import java.sql.*; O3,jg|,
/** yLvDMPj
* < `=j^LU
* @author D0-3eV-
*/ JX;<F~{.
public class CountControl{ 0*3R=7_},o
private static long lastExecuteTime=0;//上次更新时间 gh]cXuph
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]m3HF&
/** Creates a new instance of CountThread */ lfow1WRF
public CountControl() {} E4jNA}3k+
public synchronized void executeUpdate(){ vH@ds
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Connection conn=null; 2*& ^v
PreparedStatement ps=null; vm8eZG|
try{ ?(1y
conn = DBUtils.getConnection(); rH Lm\3
conn.setAutoCommit(false); &jJL"gq"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 6Pl<'3&
for(int i=0;i<CountCache.list.size();i++){ y'q$|
CountBean cb=(CountBean)CountCache.list.getFirst(); AO4U}?
CountCache.list.removeFirst(); $t[FH&c(
ps.setInt(1, cb.getCountId()); 9s
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ps.executeUpdate();⑴ Tx# Mn~xD
//ps.addBatch();⑵ N#_H6TfMG
} L,/%f<wd
//int [] counts = ps.executeBatch();⑶ .W%)*&WH\
conn.commit(); b{&)6M)zo
}catch(Exception e){ Dcgo%F-W
e.printStackTrace(); d7;um<%zn
} finally{ Se}c[|8
try{ zY{A'<\O
if(ps!=null) { jvL[
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ps.clearParameters(); Ynj,pl
ps.close(); TF\C@4Z
ps=null; S9y}
} gPI
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}catch(SQLException e){} K($Npuu]
DBUtils.closeConnection(conn); (y~TL*B
} mO7]9p
} +~$ ]}%
public long getLast(){ !wVM= z^G
return lastExecuteTime; <iC(`J$D
} j</: WRA`]
public void run(){ g*_&
long now = System.currentTimeMillis(); %ntRG!
if ((now - lastExecuteTime) > executeSep) { /$?}YL,
//System.out.print("lastExecuteTime:"+lastExecuteTime); Xl#ggub?
//System.out.print(" now:"+now+"\n"); A?P_DA
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r),kDia
lastExecuteTime=now; k="i;! Ge
executeUpdate(); ]w8(&,PP
} KkbD W3-
else{ b]#AI
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); hL{KRRf>
} \r+
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} &j"?\f?
} kn4`Fa;)O
//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 Bj;'qB>3
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类写好了,下面是在JSP中如下调用。 583|blL
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<% 1>h]{%I
CountBean cb=new CountBean(); @RKryY)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); zRr*7G
CountCache.add(cb); |)v,2
out.print(CountCache.list.size()+"<br>"); ]{@-HTt
CountControl c=new CountControl(); ( Erc3Ac8
c.run(); Kw ]=
out.print(CountCache.list.size()+"<br>"); 3F2w-+L
%>