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: quCWc2pXX
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CountBean.java w
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/* >XXMIz:
* CountData.java qj3bt_F!x
* lEYT{
* Created on 2007年1月1日, 下午4:44 ~J. Fl[
* VkN[=0a,
* To change this template, choose Tools | Options and locate the template under <*r<+S
* the Source Creation and Management node. Right-click the template and choose }n2-*{)x
* Open. You can then make changes to the template in the Source Editor. aaqd:N)
*/ O{i_?V_
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package com.tot.count; {xBjEhQm
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/** |qy"%W@
* _;J9q}X
* @author a7v[l04
*/ ]\D6;E8P-~
public class CountBean { QS=$#Gp
private String countType; %.Tf u0M
int countId; rs 1*H
/** Creates a new instance of CountData */ "k6IV&0
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public CountBean() {} R26tQbwE
public void setCountType(String countTypes){ "$V 8y
this.countType=countTypes; LD~uI
} x@ s`;qz
public void setCountId(int countIds){ +U_-Lq )
this.countId=countIds; \xO2WD
} X!+Mgh6
public String getCountType(){ |B{$URu
return countType; ,5A>:2 zs
} "{ QHWZ
public int getCountId(){ 6JFDRsX>)?
return countId; N>}K+M>
} lPFdQ8M
} (15Yw9Mv
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CountCache.java jC Kt;lj
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/* i[t=@^|
* CountCache.java 4 _U,-%/
* I_6` Z 0
* Created on 2007年1月1日, 下午5:01 iQ]c
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* v20I<!5w
* To change this template, choose Tools | Options and locate the template under M%5$-;6~_
* the Source Creation and Management node. Right-click the template and choose d a?th
* Open. You can then make changes to the template in the Source Editor. o4[2`mT
*/ :{xN33@6\X
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package com.tot.count; ;\*Od?1
import java.util.*; ,@>rubUz
/** HsgTHe
* ^9*|_\3N
* @author 55\X\>
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*/ _6-/S!7Y\
public class CountCache { *UL|{_)c
public static LinkedList list=new LinkedList(); ^qus `6
/** Creates a new instance of CountCache */ <9k}CXv2PK
public CountCache() {} kz VI:
public static void add(CountBean cb){ +@],$=aE?
if(cb!=null){ &9lc\Y4PY
list.add(cb); @H# kvYWmn
} *ckrn>E{h
} t`1]U4s&I
} hL{B9?
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CountControl.java ot+~|Dl
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/* qQ
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* CountThread.java 2#:]%y;\
* uF3p1by
* Created on 2007年1月1日, 下午4:57 HToN+z%w3H
* zkMO3w>
* To change this template, choose Tools | Options and locate the template under qp_ `Fj:
* the Source Creation and Management node. Right-click the template and choose /GSI.tO
* Open. You can then make changes to the template in the Source Editor. JdYF&~
*/ PKM$*_LcGI
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package com.tot.count; WmVw>.]@~
import tot.db.DBUtils; n#4J]Z@
import java.sql.*; 0l1]QD+Gc5
/** :*Ggz|
* h7]]F{r5
* @author @1ta`7#
*/ p vR& ~g
public class CountControl{ bSmaE7
private static long lastExecuteTime=0;//上次更新时间 }NBJ T4R
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 IK? $!jh
/** Creates a new instance of CountThread */ UlN|Oy,
public CountControl() {} Sd{"A0[A|
public synchronized void executeUpdate(){ @"0N @gU
Connection conn=null; K<w5[E9V.
PreparedStatement ps=null; >hL'#;:f#
try{ F Hcqu_;J
conn = DBUtils.getConnection(); .x$T al
conn.setAutoCommit(false); /~rO2]rZ@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [pWDhY
for(int i=0;i<CountCache.list.size();i++){ l/UG+7
CountBean cb=(CountBean)CountCache.list.getFirst(); e(\S,@VN2
CountCache.list.removeFirst(); 8'xnhV
ps.setInt(1, cb.getCountId()); ,0~
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ps.executeUpdate();⑴ 8Bt-
//ps.addBatch();⑵ fh)`kZDk
} n03SXaU~V
//int [] counts = ps.executeBatch();⑶ g5 |\G%dOt
conn.commit(); rLVc<595
}catch(Exception e){ !>@V#I
e.printStackTrace(); Iy4MMU
} finally{ P"~T*Qq-R
try{ g)D}p@>m
if(ps!=null) { I64:-P[\
ps.clearParameters(); #:zPpMAl
ps.close(); D&m"~wI
ps=null; LXF%~^^@d
} +}0*_VW
}catch(SQLException e){} eC`f8=V
DBUtils.closeConnection(conn); Jc?ssm\%
} nW%=k!''
} U`p<lxRgQ
public long getLast(){ _w/N[E
return lastExecuteTime; `LU,uz
} uv!qE1z@':
public void run(){ ~S>ba']
long now = System.currentTimeMillis(); ![!b^:f
if ((now - lastExecuteTime) > executeSep) { *g41"Cl
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5XUI7Q%
//System.out.print(" now:"+now+"\n"); =l'_*B8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6ch[B`[h,
lastExecuteTime=now; QIV~)`;
executeUpdate(); ZL@DD(S-/
} &&S4x
else{ eRy'N|'
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); GWZXRUc
} t8N9/DZ}Q
} RWQW/Gwx
}
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//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 QGj5\{E_
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类写好了,下面是在JSP中如下调用。 1WN93SQ=
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<% W}_}<rlF
CountBean cb=new CountBean(); HU+H0S~g
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _rJSkZO
CountCache.add(cb); Z_~DTO2Qg
out.print(CountCache.list.size()+"<br>"); FEmlC,%
CountControl c=new CountControl(); gj;G:;1m
c.run(); uWj-tzu
out.print(CountCache.list.size()+"<br>"); 76r
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