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: QbY@{"" `
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CountBean.java V7cr%tY5
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/* Dv&K3^~Rfb
* CountData.java p%K(dA
* t 6lwKK
* Created on 2007年1月1日, 下午4:44 x0) WrDb
* r\)bN4-g
* To change this template, choose Tools | Options and locate the template under C;.,+(G
* the Source Creation and Management node. Right-click the template and choose }<*KM)%
* Open. You can then make changes to the template in the Source Editor. BO%'/2eV
*/ -=ZDfM
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package com.tot.count; k|U2Mp
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/** yhs:.h
* OB*V4Yv
* @author v-/vj/4>
*/ $dA]GWW5A
public class CountBean { 15r=d
private String countType; {w7/M]m-
int countId; ExeZj8U
/** Creates a new instance of CountData */ \NKQ:F1
public CountBean() {} FW|_8q?}<
public void setCountType(String countTypes){ %.onO0})
this.countType=countTypes; 7+qKA1t^
} ''3I0X*!
public void setCountId(int countIds){ Wrh$`JC
this.countId=countIds; ?0?3yD-!9
} @7KG0<]h
public String getCountType(){ 8 )n g> l
return countType; ?GW}:'z
} ;~'& m
public int getCountId(){ W!Fc60>p@f
return countId; 6Rmdf>a
} @PctBS<s
} (NN;1{DB8
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CountCache.java S5d
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/* %$i}[U
* CountCache.java W+$G{XSr5C
* ? Dn}
* Created on 2007年1月1日, 下午5:01 dC|6z/
* )4m`Ya,E3
* To change this template, choose Tools | Options and locate the template under TBRG
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* the Source Creation and Management node. Right-click the template and choose P+wpX
* Open. You can then make changes to the template in the Source Editor. =|8hG*D8
*/ l5\V4
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package com.tot.count; gga}mqMv=
import java.util.*; yxU9W,D v
/** /bPs0>5
* KSHq0A6/q%
* @author 76KNgV)3
*/ ={+8jQqi1
public class CountCache { b&dv("e
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public static LinkedList list=new LinkedList(); -Mz [S
/** Creates a new instance of CountCache */ d ez4g
public CountCache() {} ]}p<P):hO
public static void add(CountBean cb){ "/mtuU3rt
if(cb!=null){ O?cU6u;W
list.add(cb); S>S7\b'
} =O-irGms*
} 9y<h.T
} -4zV
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CountControl.java F=e-jKogK
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/* h9#)Eo
* CountThread.java UGj |)/
* fc9@l a
* Created on 2007年1月1日, 下午4:57 '+27_j
* ${eV3LSC
* To change this template, choose Tools | Options and locate the template under R=F_U
* the Source Creation and Management node. Right-click the template and choose 0U H]
* Open. You can then make changes to the template in the Source Editor. :2&"ak>N
*/ Z#bO}!
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package com.tot.count; c+ByEP4EG
import tot.db.DBUtils; x~wS/y
import java.sql.*; -a &<Un/
/** &I[` .:NJ
* $/B~ bJC
* @author bI8uw|c
*/ ,isjiy
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public class CountControl{ %.?V\l
private static long lastExecuteTime=0;//上次更新时间
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :O$bsw:3w<
/** Creates a new instance of CountThread */ OZnKJ<
public CountControl() {} Bc[~'gn
public synchronized void executeUpdate(){ w,$qsmR
Connection conn=null; "H<us?r{
PreparedStatement ps=null; k)|.<
try{ ;i'[c`
conn = DBUtils.getConnection(); L+(ng
conn.setAutoCommit(false); zsJermF,O
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); |ns?c0rM
for(int i=0;i<CountCache.list.size();i++){ )>S,#_e*b
CountBean cb=(CountBean)CountCache.list.getFirst(); Z6A-i@
CountCache.list.removeFirst(); nSC2wTH!1
ps.setInt(1, cb.getCountId()); JXYZ5&[
ps.executeUpdate();⑴ > pP&/
//ps.addBatch();⑵ "=T&SY
} dRnf
//int [] counts = ps.executeBatch();⑶ XWyP'\
conn.commit(); _lFw1pa#\
}catch(Exception e){ l
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e.printStackTrace(); "\KBF
} finally{ G3%Ju=
try{ _]pu"hZz4
if(ps!=null) { j7k}!j_O{
ps.clearParameters(); +a1iZ bh
ps.close(); >3Q|k{97
ps=null; aR/?YKA
} RZ xwr
}catch(SQLException e){} =R|XFZ,
DBUtils.closeConnection(conn);
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} W ';X4e
} i>s
public long getLast(){ -p.\fvip
return lastExecuteTime; ZcQu9XDIt
} DQm%=ON7
public void run(){ e)g&q'O
long now = System.currentTimeMillis(); VL$
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if ((now - lastExecuteTime) > executeSep) { $
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//System.out.print("lastExecuteTime:"+lastExecuteTime); OmO#} k<
//System.out.print(" now:"+now+"\n"); G7Sw\wW
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "cPg_-n
lastExecuteTime=now; uMS+,dXy
executeUpdate(); u0 tlf
} ?!6Itkg
else{ @2)nhW/z6
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); %dFJ'[jDL
} ?(R3%fU
} xI{4<m/0N
} cN8Fn4gq
//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 dQ.#8o=
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类写好了,下面是在JSP中如下调用。 t'l4$}(
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<% r(46jV.sD:
CountBean cb=new CountBean(); "+-
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); K+F"V W*?
CountCache.add(cb); _!@:@e)yB{
out.print(CountCache.list.size()+"<br>"); zqo0P~
CountControl c=new CountControl();
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c.run(); L ,dh$F
out.print(CountCache.list.size()+"<br>"); d*0RBgn
%>