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: G!k&'{2
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CountBean.java W$ #FM$U
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/* |{+D65R
* CountData.java v9INZ1# v
* 9=pG$+01OR
* Created on 2007年1月1日, 下午4:44 ! lgsV..R
* P%f],f
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose +4f>njARIb
* Open. You can then make changes to the template in the Source Editor. Bvzl*
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*/ *qYcb}
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package com.tot.count; V"(S<o
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/** {MU>5\
* .2/(G{}U
* @author -fuSCj
*/ :pcKww|V
public class CountBean { /E$"\md
private String countType; jFpXTy[>
int countId; 6UR.,*f=
/** Creates a new instance of CountData */ {o<
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public CountBean() {} aM5zYj`pW
public void setCountType(String countTypes){ lBh|+KN
this.countType=countTypes; 1@RctI_}
} S9}P5;u
public void setCountId(int countIds){ BbUZ,X*Y
this.countId=countIds; \ }>1$kH;
} )`yxJ;O@$
public String getCountType(){ L B1ui
return countType; RS!~5nk5
} c 6@!?8J
public int getCountId(){ N,V%/O{Y
return countId; Fh9`8
} .,(bDXl?
} e4u$+
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CountCache.java &e@2zfl7
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/* {uh]b(}s)
* CountCache.java b+yoD
* A;m)/@
* Created on 2007年1月1日, 下午5:01 ViQxOUE
* /Z HuT=j1
* To change this template, choose Tools | Options and locate the template under l;}D| 6+_W
* the Source Creation and Management node. Right-click the template and choose ]=of=T:
* Open. You can then make changes to the template in the Source Editor. ==`K$rM
*/ oQI3Yz
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package com.tot.count; +u'
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import java.util.*; U0t/(Jyg
/** OJ\IdUZ
* J!O5`k*.C
* @author /vS!9f${
*/ v' .:?9
public class CountCache { _%w-y(Sqn
public static LinkedList list=new LinkedList(); Q\&FuU
/** Creates a new instance of CountCache */ .9+"rK}u
public CountCache() {} %/b?T]{
public static void add(CountBean cb){ ^-cj=on=Q
if(cb!=null){ hNmC(saMGm
list.add(cb); #P=rP=
} &}@U#w]l
} R8P7JY[h
} &G7JGar
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CountControl.java o$oW-U
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/* |`_qmk[:R
* CountThread.java Enm#\(j
* //]g78]=O
* Created on 2007年1月1日, 下午4:57 {ER!
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* SY>i@s+ML
* To change this template, choose Tools | Options and locate the template under KhAj`vOzK
* the Source Creation and Management node. Right-click the template and choose J?Brnf.
* Open. You can then make changes to the template in the Source Editor. z kQV$n{
*/ )Q9m,/F
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package com.tot.count; ^;@q^b)ZP
import tot.db.DBUtils; W_9-JM(r
import java.sql.*; vt<r_&+ pJ
/** W,5A|Q~
* u$$@Hw
* @author 5:/
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*/ 3Ba>a(E
public class CountControl{ v+f:VA
private static long lastExecuteTime=0;//上次更新时间 a'U7 t
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,$EM3
/** Creates a new instance of CountThread */ WM5s
public CountControl() {} ZQ9!k*
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public synchronized void executeUpdate(){ V|KYkEl
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Connection conn=null; '; ,DgR;'
PreparedStatement ps=null; JO\Tf."a \
try{ n3t1'_/TU}
conn = DBUtils.getConnection(); [H)NkR;I
conn.setAutoCommit(false); v]\io#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ]+;1)
for(int i=0;i<CountCache.list.size();i++){ 0ohpJh61Q
CountBean cb=(CountBean)CountCache.list.getFirst(); )$Xd#bzD|
CountCache.list.removeFirst(); :zdMV6s
ps.setInt(1, cb.getCountId()); j9n3
ps.executeUpdate();⑴ dqO!p6
//ps.addBatch();⑵ _"_ W KlN
} ~Z!!wDHS
//int [] counts = ps.executeBatch();⑶ }UJS*mR
conn.commit(); p0~=
}catch(Exception e){ |>@Gbgw^M
e.printStackTrace(); CwZ+Pn0
} finally{ =)vmX0vL
try{ /fbI4&SB!
if(ps!=null) { $r)+7i
ps.clearParameters(); xZW6Hk_
ps.close(); 4V9DPBh
ps=null; WL$Ee=
} 8rwkux >
}catch(SQLException e){} {2G9>'
DBUtils.closeConnection(conn); S453oG"
} l?v`kAMR
} tgK$}#.*
public long getLast(){ uSCF;y=1g,
return lastExecuteTime; QEK,mc3
} {Ak{
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public void run(){ t=syo->
long now = System.currentTimeMillis(); n0g,r/
if ((now - lastExecuteTime) > executeSep) { H_KE^1
//System.out.print("lastExecuteTime:"+lastExecuteTime); R}njFQvS)
//System.out.print(" now:"+now+"\n"); Qg;A (\z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); O^ZOc0<
lastExecuteTime=now; 4of3#M
executeUpdate(); xO)vn\uJ
} c;c'E&9P]
else{ R+k-mbvnt
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} H6(kxpOI\
} s8Kf$E^?e.
} 'b#RfF,7H}
//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 yE[ -@3v
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类写好了,下面是在JSP中如下调用。 T-ID{i
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<% 6}wXNTd
CountBean cb=new CountBean(); H~E(~fl
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); sKYb&2wJ
CountCache.add(cb); CAyV#7[0
out.print(CountCache.list.size()+"<br>"); EM]~yn!+
CountControl c=new CountControl(); 1| "s_m>g
c.run(); 7^,C=2
out.print(CountCache.list.size()+"<br>"); Ci6yH( RE
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