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: 'id]<<F
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CountBean.java sOQF_X(.x
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/* In<L?U?([D
* CountData.java sH(@X<{p
* <Yif-9
* Created on 2007年1月1日, 下午4:44 E_ #MQ;n
* yE1M+x./
* To change this template, choose Tools | Options and locate the template under AJ1(q:P
* the Source Creation and Management node. Right-click the template and choose ye!}hm=w
* Open. You can then make changes to the template in the Source Editor. lJ1_Zs `
*/ ZZ|a`U
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package com.tot.count; hUN]Lm6M
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/** AWsy9
* LE#ko2#ke
* @author &Z3g$R 9
*/ U\dq
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public class CountBean { 30cZz
private String countType; H*s_A/$
int countId; =pSuyM'
/** Creates a new instance of CountData */ <\40?*2
public CountBean() {} B'<k*9=Nv8
public void setCountType(String countTypes){ [\+"<;m$
this.countType=countTypes; GIG\bQSv2
} z !2-U
public void setCountId(int countIds){ mNhVLB
this.countId=countIds; .H;[s
} 9+><:(,
public String getCountType(){ r:.3P
return countType; bWU4lPfP
} D&0y0lxI@
public int getCountId(){ =M39I&N
return countId; l`"i'P
} {6}H}_(]
} \o}m]v
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CountCache.java vw(X9xa
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/* #( G>J4E,
* CountCache.java j8gw]V/B:
* +$_.${uwV
* Created on 2007年1月1日, 下午5:01 Y.FqWJP=p
* n~`1KC4
* To change this template, choose Tools | Options and locate the template under zb<YYJ]
* the Source Creation and Management node. Right-click the template and choose 'VVEd[
* Open. You can then make changes to the template in the Source Editor. ;QZ}$8D 6Q
*/ E&js`24 &
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package com.tot.count; 4R<bfZ43
import java.util.*; 5MU-Eu|*>
/** dZ]['y%
* cPu<:<F[
* @author 0i%r+_E_
*/ SbrKNADH%
public class CountCache { NmbA~i
public static LinkedList list=new LinkedList(); vxN,oa{hf
/** Creates a new instance of CountCache */ G!Gbg3:4e5
public CountCache() {} P[Q3z$I}
public static void add(CountBean cb){ O>FE-0rW}e
if(cb!=null){ S:b-+w|*
list.add(cb); <WPLjgtn3
} b{X,0a{*
} 6yU#;|6d
} |t <Uh,Bt
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CountControl.java VR:4|_o
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/* [22>)1<(
* CountThread.java
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* $eqwn&$n
* Created on 2007年1月1日, 下午4:57 p>9-Ga
* acG4u+[ ]
* To change this template, choose Tools | Options and locate the template under V@%:y tDf
* the Source Creation and Management node. Right-click the template and choose s1"dd7&g'
* Open. You can then make changes to the template in the Source Editor. `?M?WaP
*/ pGO=3=O
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package com.tot.count; yxz)32B?
import tot.db.DBUtils; Wra$
import java.sql.*; "CH3\O\
/** L_ &`
* ',>Pz+XKc
* @author jPu m2U_
*/ YoU|)6Of
public class CountControl{ %t.L;G
private static long lastExecuteTime=0;//上次更新时间
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ^ "
/** Creates a new instance of CountThread */ ] x12_+
public CountControl() {} '=eG[#gy
public synchronized void executeUpdate(){ 4 C7z6VWg
Connection conn=null; Ad%3 fvn
PreparedStatement ps=null; V1h&{D\"
try{ 16pk4f8
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); P84uEDY
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >)+-:
for(int i=0;i<CountCache.list.size();i++){ s28t'
CountBean cb=(CountBean)CountCache.list.getFirst(); &-e@Et`Pg
CountCache.list.removeFirst(); K*"Wq:T;B
ps.setInt(1, cb.getCountId()); Y<vHL<G
ps.executeUpdate();⑴ cM|!jnKm
//ps.addBatch();⑵ Tl/!Dn
} ()\=(n!J
//int [] counts = ps.executeBatch();⑶ v4$"{W;'
conn.commit(); vGIe"$hNh
}catch(Exception e){ C]- !uLy
e.printStackTrace(); qcWY8sYf
} finally{ .5s#JL
try{ gL/D| =
if(ps!=null) { _Qh:*j!
ps.clearParameters(); *i`t4N
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ps.close(); }HLs.k4-;
ps=null; eI@nskq#
} @Q%9b )\\
}catch(SQLException e){} AP:(/@K|
DBUtils.closeConnection(conn); a7~%( L@r
} e]!`Cl-f80
} 9P7^*f:E
public long getLast(){ AJJa<c+j
return lastExecuteTime; P #PRzt
} 7kT&}`g.
public void run(){ G*y!
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long now = System.currentTimeMillis(); 50E?K!
if ((now - lastExecuteTime) > executeSep) { l>t0 H($
//System.out.print("lastExecuteTime:"+lastExecuteTime); +m>)q4e
//System.out.print(" now:"+now+"\n"); J^y}3ON
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); -u nK;
lastExecuteTime=now; U)sw
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executeUpdate(); 9!>Ks8'.d
} Y<WA-dYoF
else{ >;NiG)Z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); @
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} E&_q"jJRi
} ?cvV~&$gc
} r`OC5IoQ
//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 ~c\iBk
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类写好了,下面是在JSP中如下调用。 +qiI;C_P\
#-<n@qNg[
<% FPC^-mD
CountBean cb=new CountBean(); 4))5l9kc.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *U}cj A:ZN
CountCache.add(cb); W|I<hY\X
out.print(CountCache.list.size()+"<br>"); :G8:b.
CountControl c=new CountControl(); ]IM/R@
c.run(); E=&":I6O
out.print(CountCache.list.size()+"<br>"); 04E
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%>