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: I{&[[7H
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CountBean.java CxmKz78
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/* zI uJ-8T"
* CountData.java kH1~k,|\&K
*
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* Created on 2007年1月1日, 下午4:44 VGN5<?PrN
* #%2rP'He
* To change this template, choose Tools | Options and locate the template under 6_;icpN]
* the Source Creation and Management node. Right-click the template and choose E&w7GZNt
* Open. You can then make changes to the template in the Source Editor. G!##X: 6'
*/ VQ@
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package com.tot.count; ,qwuLBW
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/** IP pN@
* >R_&Ouh:
* @author 1&OW4_
*/ .Hm>i
public class CountBean { 3}1u\(Mf
private String countType; T!{w~'=F
int countId; ^76]0`gS
/** Creates a new instance of CountData */ WU`
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public CountBean() {} Fo_sgv8O<
public void setCountType(String countTypes){ ~~P5k:
this.countType=countTypes; @mBQ?;qlK
} n@i HFBb
public void setCountId(int countIds){ Ml5w01O
this.countId=countIds; Q&;9x? e
} 00y!K
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public String getCountType(){ |df Pki{
return countType; Qv-_ jZ
} _H%c;z+
public int getCountId(){ `wVyb>T
return countId; @. l@\4m
} ^CX6&d
} 3$R1ipb
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CountCache.java kzLsoZ!I
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/* 8<.Oq4ku
* CountCache.java LRA8p<Rs
* kevrsV]/$
* Created on 2007年1月1日, 下午5:01 Sm|6 %3
* 2ilQXy
* To change this template, choose Tools | Options and locate the template under CTa57R
* the Source Creation and Management node. Right-click the template and choose 6{b>p+U
* Open. You can then make changes to the template in the Source Editor. >bW#Zs,6
*/ a=2%4Wmz
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package com.tot.count; i.m^/0!
import java.util.*; 6&x@.1('z
/** wHy!CP%
* ~>|ziHx
* @author 4B.*g-L
*/ 5b*C1HS@X
public class CountCache { |{ip T SH
public static LinkedList list=new LinkedList(); .k !{*
/** Creates a new instance of CountCache */ bH~dJFj/
public CountCache() {} "to;\9lP
public static void add(CountBean cb){ k(HUUH_z
if(cb!=null){ ;Y, y 4{H3
list.add(cb); W<g1<z\f
} U K!(G
} ygcm|PrS
} }K(TjZR
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CountControl.java W=?<<dVYD
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/* [/r(__.
* CountThread.java _[BP0\dPW
* tw@X>
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* Created on 2007年1月1日, 下午4:57 L/K(dkx
* wCBplaojJ
* To change this template, choose Tools | Options and locate the template under p_4<6{KEt
* the Source Creation and Management node. Right-click the template and choose gSj,E8-g
* Open. You can then make changes to the template in the Source Editor. flx(HJK
*/ (ZlU^Gw#UB
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package com.tot.count; HoAy_7-5
import tot.db.DBUtils; .%-8 t{dt
import java.sql.*; V7/Rby Q
/** 8ao _i=&x
* !4!~Lk=
* @author Id9TG/H7
*/ ]?4hyN
public class CountControl{ Fr-SvsNFB
private static long lastExecuteTime=0;//上次更新时间 Z\sDUJ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 M6TD"-
/** Creates a new instance of CountThread */ 7_t'( /yu
public CountControl() {} Z_NCD`i;
public synchronized void executeUpdate(){ eMzk3eOJ
Connection conn=null; !)$Zp\Sg
PreparedStatement ps=null; `]aeI'[}R
try{ W,u:gzmhw
conn = DBUtils.getConnection(); <UCl@5g&
conn.setAutoCommit(false); nk:)j:fr
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +7}]E1Uf
for(int i=0;i<CountCache.list.size();i++){ rC5O")I<
CountBean cb=(CountBean)CountCache.list.getFirst(); eS!/(#T
CountCache.list.removeFirst(); ssL\g`xe
ps.setInt(1, cb.getCountId()); :Dp0?&_
ps.executeUpdate();⑴ 5V-I1B&
//ps.addBatch();⑵ 5r0YA
IJ
} KPki}'GO
//int [] counts = ps.executeBatch();⑶ 'GScszz
conn.commit(); a q-~B~c`g
}catch(Exception e){ v[<T]1=LRC
e.printStackTrace(); H?w6C):]
} finally{ ;VK.2^jW!
try{ wC*X4 '
if(ps!=null) { <3
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ps.clearParameters(); gGuO
ps.close(); jiGTA:v
ps=null; 2<6UwF
} E-FUlOG&
}catch(SQLException e){} MK*r+xfSae
DBUtils.closeConnection(conn); (k P9hcV
} {`_i`
} +7a6*;\ y
public long getLast(){ a9Vi];
return lastExecuteTime; \<K5ZIWV
} I+(nu47ZT
public void run(){ ^rz_f{c]-
long now = System.currentTimeMillis(); N>E_%]C h
if ((now - lastExecuteTime) > executeSep) { gDzK{6Z}
//System.out.print("lastExecuteTime:"+lastExecuteTime); p4QU9DF
//System.out.print(" now:"+now+"\n"); {{1G`;|v9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?A0)L27UE&
lastExecuteTime=now; fV~~J2IK
executeUpdate(); dWW.Y*339
} GX%g9f!O
else{ -RLOD\ZBh
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); HKe K<V
} ig"L\ C"T
} fsXy"#mOkD
} g{LP7D;6
//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 MfkZ
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类写好了,下面是在JSP中如下调用。 Xc.`-J~Il
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<% sRfcF`7
CountBean cb=new CountBean(); <naz+QK'
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8EY:tzw
CountCache.add(cb); M\=2uKG#
out.print(CountCache.list.size()+"<br>"); T{'RV0%
CountControl c=new CountControl();
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c.run(); 2zpr~cB=
out.print(CountCache.list.size()+"<br>"); ,,TnIouy
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