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: iW;i!,
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CountBean.java /L v1$~
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/* %8mm Hh
* CountData.java +E5=$`
* h*w6/ZL1
* Created on 2007年1月1日, 下午4:44 ? \m3~6y
* @{d\j]Nw
* To change this template, choose Tools | Options and locate the template under <7)Fh*W@
* the Source Creation and Management node. Right-click the template and choose s0C:m
* Open. You can then make changes to the template in the Source Editor. kl}Xmw{tJ
*/ _xrwu;o0}
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package com.tot.count; :243 H
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/** "A3dvr
* )TJS4?
* @author 2e1]}wlK
*/ 27D!'S
public class CountBean { _A+w#kiv>
private String countType; 4=[7Em?oLb
int countId; x /mp=
/** Creates a new instance of CountData */ L{8;Ud_2r
public CountBean() {} $_D6_|HK
public void setCountType(String countTypes){ 6f)2 F<
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this.countType=countTypes; HpW 42
} SVWIEH0?
public void setCountId(int countIds){ $t/rOo9cV
this.countId=countIds; bRo|uJ:d
} %Mn.e a
public String getCountType(){ 1n=_y o
return countType; L":bI&V?:
} _P7tnXww
public int getCountId(){ 1S:|3W
return countId; SJ?)%[(T
} #VGjCEeU
} b]Z@^<_E
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CountCache.java 4n0xE[-
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/* cYNV\b4-
* CountCache.java lr@#^
* 8g~EL{'
* Created on 2007年1月1日, 下午5:01 q]% T:A=
* T:iP="?{
* To change this template, choose Tools | Options and locate the template under 1(#;&:$`i
* the Source Creation and Management node. Right-click the template and choose d8o53a]
* Open. You can then make changes to the template in the Source Editor. -db75=
*/ \3XqHf3|o
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package com.tot.count; Pm{*.AW1
import java.util.*; </"4 zD|
/** $_;e>*+x
* 1wj:aD?g
* @author If-_?wZe
*/ T7*wS#z)h
public class CountCache { !#yq@2QX
public static LinkedList list=new LinkedList(); &1|?BZv
/** Creates a new instance of CountCache */ K>/%X!RW
public CountCache() {} \2C`<h$fN
public static void add(CountBean cb){ {zLhiUH
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if(cb!=null){ 3ec`Wa
list.add(cb); iw9Q18:I}
} 5F"|E-;
} B4Y(?JTx
} #*%q'gyHT
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CountControl.java ~x:DXEV,
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/* v-b0\_
* CountThread.java lUOvm\
* $md%xmQ[
* Created on 2007年1月1日, 下午4:57 c=O,;lWFqm
* w'T q3-%V
* To change this template, choose Tools | Options and locate the template under -~{c
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* the Source Creation and Management node. Right-click the template and choose K2)!h.W
* Open. You can then make changes to the template in the Source Editor. iBg3mc@OO
*/ uQ1@b-e`5
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package com.tot.count; b*kfWG-6t
import tot.db.DBUtils; #-VMg+14
import java.sql.*; hfWFD,
/** J:*-gwv9*m
* "SxLN
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* @author feM6K!fL`
*/ ZP\M9Ja
public class CountControl{ bm~W
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private static long lastExecuteTime=0;//上次更新时间 C4$:mJ>y
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Sl2iz?
/** Creates a new instance of CountThread */
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public CountControl() {} 7cDU2l
public synchronized void executeUpdate(){ {7hLsK[])
Connection conn=null; BR`ygrfe
PreparedStatement ps=null;
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try{ <W8t|jt
conn = DBUtils.getConnection(); 4*n#yVb/
conn.setAutoCommit(false); +n0r0:z0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); p{A}pnjf
for(int i=0;i<CountCache.list.size();i++){ '@|_OmcY
CountBean cb=(CountBean)CountCache.list.getFirst(); 1$/MrPT(b
CountCache.list.removeFirst(); &F
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ps.setInt(1, cb.getCountId()); 82{ Vc
ps.executeUpdate();⑴ 5|0,X<&
//ps.addBatch();⑵ yF}OfK?0f
} ))kF<A_MK
//int [] counts = ps.executeBatch();⑶
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conn.commit(); f"G-
}catch(Exception e){ CvSIV7zYo
e.printStackTrace(); ?Ea;J0V
} finally{ j l.p'$Fbn
try{ f
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if(ps!=null) { z
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ps.clearParameters(); 5^<h}u9
ps.close(); \uqjs+
ps=null; tsOrt3
} 2,2Z`X
}catch(SQLException e){} t.8 GT&p
DBUtils.closeConnection(conn); 2"P99$"
} 6k{2 +P
} ,_aM`%q?Fj
public long getLast(){ <P[T!gST
return lastExecuteTime; bK"SKV
} i$G;f^Z!Y
public void run(){ (
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long now = System.currentTimeMillis(); H`bSYjgM!
if ((now - lastExecuteTime) > executeSep) { K%<j=c
//System.out.print("lastExecuteTime:"+lastExecuteTime); g6@Fp7T
//System.out.print(" now:"+now+"\n"); c .3ZXqpI;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,u }XWV
lastExecuteTime=now; ^H{R+}
executeUpdate(); (/!r(#K0,'
} #4MBoN(3
else{ <9E0iz+j
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ptatzp]c#
} 5Wyz=+?m|
} 4'j
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} H&1[nU{?>
//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 q5h*`7f
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类写好了,下面是在JSP中如下调用。 f0<hE2
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<% 1_fZm+oW!
CountBean cb=new CountBean(); ;{i'#rn{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #/"8F O%~p
CountCache.add(cb); WV3|?,y]qm
out.print(CountCache.list.size()+"<br>"); F|Mi{5G%
CountControl c=new CountControl(); ZUz ^!d
c.run(); Re:jVJgBz
out.print(CountCache.list.size()+"<br>"); 6:GTD$Uz.
%>