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: 7Rr
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CountBean.java J}VG4}L
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/* u5P2*
* CountData.java f5t/=/6>F
* j@jUuYuDgl
* Created on 2007年1月1日, 下午4:44 0SDyE
* \2 `|eo
* To change this template, choose Tools | Options and locate the template under gCI{g.[I!
* the Source Creation and Management node. Right-click the template and choose h}GzQry1
* Open. You can then make changes to the template in the Source Editor. S),acc(d
*/ H')8p;~{}
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package com.tot.count; 2Ni {fC?
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/** oMb@)7
* kfs[*ku
* @author rn-CQ2{?
*/ 5oY^;)\/
public class CountBean { =zwn3L8 fL
private String countType; yRldPk_
int countId; _VLA2#V>
/** Creates a new instance of CountData */ eh6=-
public CountBean() {} ^" UZ.@sq'
public void setCountType(String countTypes){ `R_;n#3F0
this.countType=countTypes; 2?(dS
} z~RE}k
public void setCountId(int countIds){ Nb/Z +
this.countId=countIds; ~d=Y98'xS
} ~|8-Mo1ce
public String getCountType(){ 2fMKS
return countType; sK|+&BC
} "l-R|>6~
public int getCountId(){ Uf\U~wM<
return countId; $xq$
} 9at_F'>R
} I73=PfS:m
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CountCache.java SH1)@K-
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/* 0hOps5c8=
* CountCache.java h5
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* Q;eY]l8
* Created on 2007年1月1日, 下午5:01 "|d# +C
* p2(Z(V7*
* To change this template, choose Tools | Options and locate the template under L<ET"&b;4
* the Source Creation and Management node. Right-click the template and choose LZ1)zoJ
* Open. You can then make changes to the template in the Source Editor. /n8\^4{fP{
*/ Kr@6m80E5
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package com.tot.count; ' )KuLVE}S
import java.util.*; C5EaP%s
/** DDp\*6y3l
* \~I>@SG2W+
* @author zIbrw9G
*/ h~u|v[@{J
public class CountCache { vW`[CEm^X
public static LinkedList list=new LinkedList(); Fz@9
@
/** Creates a new instance of CountCache */ $3^Cp_p6
public CountCache() {} ix_&<?8
public static void add(CountBean cb){ ~qezr\$2
if(cb!=null){ CjUYwAy$k
list.add(cb); o6)U\z
} `E8D5'tt
} kuW^_BROJ
} r5'bt"K\>
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CountControl.java F%G} >xn
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/* kJ.0|l0
* CountThread.java ?dAy_|
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* EEj.Kch}4
* Created on 2007年1月1日, 下午4:57 hf< [$B
* o!W(
* To change this template, choose Tools | Options and locate the template under D7v_<
* the Source Creation and Management node. Right-click the template and choose P$*9Z@
* Open. You can then make changes to the template in the Source Editor. zAH6SaI$
*/ X
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package com.tot.count; EfGy^`,'G
import tot.db.DBUtils; 80 ckh
import java.sql.*; OzAxnd\.N
/** 5N:IH@
* $Ahe Vps@@
* @author "43F.!P
*/ N%!{n7`N:
public class CountControl{ 9i+`,r
private static long lastExecuteTime=0;//上次更新时间 >IJX=24Rc
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 F $1f8U8
/** Creates a new instance of CountThread */ kxt/I<cs
public CountControl() {} c]R27r E
public synchronized void executeUpdate(){ N}KL'
Connection conn=null; ^JAp#?N^9
PreparedStatement ps=null; 8QQh1q2
try{ 3_ko=& B$
conn = DBUtils.getConnection(); (ty&$
conn.setAutoCommit(false); DIx.a^LR
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); J7+[+Y
for(int i=0;i<CountCache.list.size();i++){ 59BB-R,V
CountBean cb=(CountBean)CountCache.list.getFirst(); 9E}JtLgT
CountCache.list.removeFirst(); t
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ps.setInt(1, cb.getCountId()); a6\`r^ @
ps.executeUpdate();⑴ eD!mR3Ai@D
//ps.addBatch();⑵ *1,4#8tB
} ;Pe=cc"@
//int [] counts = ps.executeBatch();⑶ 1C(sBU"
conn.commit(); +P%k@w#<Z
}catch(Exception e){ Ik-E_U2
e.printStackTrace(); y'(a:.%I
} finally{ VE?Aa
try{ "w3%BbI x
if(ps!=null) { (h'Bz6K
ps.clearParameters(); r0*Y~
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ps.close(); iAZbh"I
ps=null; F(|XJN
} NiD_ v
}catch(SQLException e){} UHR%0ae
DBUtils.closeConnection(conn); Lr0:yo
} Y-lTPR<Eq
} G%viWWTY
public long getLast(){ CZog?O}<
return lastExecuteTime; ]Hg6Mz>Mj
} t8M\
public void run(){ UT0}Ce>e
long now = System.currentTimeMillis(); 7QRkXs
if ((now - lastExecuteTime) > executeSep) { \&[(PNl
//System.out.print("lastExecuteTime:"+lastExecuteTime); wU|jw(
//System.out.print(" now:"+now+"\n"); `RXlqj#u
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); k%VYAON
lastExecuteTime=now; $i%#fN
executeUpdate(); "EwzuM8f
} 8J:=@X^}
else{ R5&<\RI0
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 934@Z(aUH
} Hb0_QT~
} EVP{7}K1
} l2ie\4dK@
//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 k~)@D| ?
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类写好了,下面是在JSP中如下调用。 h
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<% 2S-f5&o
CountBean cb=new CountBean(); #_WkV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); N5zx# g
CountCache.add(cb); -F_cBu81V
out.print(CountCache.list.size()+"<br>"); & H8 %
CountControl c=new CountControl(); 3n~O&{
c.run(); HvmE'O8
out.print(CountCache.list.size()+"<br>"); Iw?*y.z|
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