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: 'BUfdb8d
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CountBean.java )G;Hf?M
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/* t%O)Ti
* CountData.java E3(o}O
* >Q'*~S@v3
* Created on 2007年1月1日, 下午4:44 L&rtN@5;
* :0ltq><?
* To change this template, choose Tools | Options and locate the template under 8_ascvs5
* the Source Creation and Management node. Right-click the template and choose W]Nc6B*gI
* Open. You can then make changes to the template in the Source Editor. y\4/M6
*/ >|`1aCg,
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package com.tot.count; 2.=G
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/** WJ)4rQ$o
* sxS%1hp3
* @author "LH!Trl@k
*/ +sTPTCLE
public class CountBean { hrO9_B|#
private String countType; 2#00<t\
int countId; Sk C.A?
/** Creates a new instance of CountData */ !G6h~`[
public CountBean() {} uix/O*^
public void setCountType(String countTypes){ +Wgfxk'{
this.countType=countTypes; 19-V;F@;
} xX9snSGz
public void setCountId(int countIds){ fP6.
this.countId=countIds; UCkV;//.
} #0Uz1[
public String getCountType(){ Ryygq,>VD.
return countType; Vy| 4k2
} *0eV9!y
public int getCountId(){ Jf0i$
return countId; Gg]Jp:GF
} s[dIWYs#
} [k(b<'
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CountCache.java @|sBnerE
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/* Mu-kvgO`L
* CountCache.java Fq!_VF^r
* C(h Td%
* Created on 2007年1月1日, 下午5:01 !*HJBZ]q
* [)dIt@Y&j
* To change this template, choose Tools | Options and locate the template under ?E(X>tH
* the Source Creation and Management node. Right-click the template and choose !f&hVLs0
* Open. You can then make changes to the template in the Source Editor. `u7^r^>A
*/ RHpjJZUV
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package com.tot.count; C"mWO Y2]
import java.util.*; lN8l71N^
/** 1
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* >dJ~
* @author [}GK rI
*/ ~iQBgd@D^
public class CountCache { #d*gWwnx"
public static LinkedList list=new LinkedList(); 6O.kKhk
/** Creates a new instance of CountCache */ Q4/BpKL
public CountCache() {} olA+B
public static void add(CountBean cb){ NI.ROk1{+4
if(cb!=null){ 1E'PSq
list.add(cb); ,!GoFu
} =au!rda
} fH?A.JP=a
} l?rLadvc
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CountControl.java a
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/* aI;$N|]u
* CountThread.java QtXiUx^ k<
* vD:J!|hs(
* Created on 2007年1月1日, 下午4:57 :ir3u
* YTmHht{j#
* To change this template, choose Tools | Options and locate the template under \%bJXTK&W
* the Source Creation and Management node. Right-click the template and choose (=fLWK{8
* Open. You can then make changes to the template in the Source Editor. &WL::gy_S
*/ r}^1dO
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package com.tot.count; /':64#'
import tot.db.DBUtils; [hpkE lE
import java.sql.*; V=th-o3[
/** GG<0k\RN
* {:VK}w
* @author H_t0$x(\
*/ <6Y;VH^_
public class CountControl{ 'W4v>0
private static long lastExecuteTime=0;//上次更新时间 %eW7AO>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 YcclO
/** Creates a new instance of CountThread */ ov H'_'
public CountControl() {} O"EL3$9V
public synchronized void executeUpdate(){ |e+3d3T35
Connection conn=null; Uf]$I`T#
PreparedStatement ps=null; o@_i&4[MW
try{ "aI)LlyCY
conn = DBUtils.getConnection(); D.%%D%AdB
conn.setAutoCommit(false); %t!r
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); o<Mccj
for(int i=0;i<CountCache.list.size();i++){ )\VuN-d
CountBean cb=(CountBean)CountCache.list.getFirst(); zTfjuI|R
CountCache.list.removeFirst(); )V>zXy}Y
ps.setInt(1, cb.getCountId()); j6~`C
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ps.executeUpdate();⑴ =q)+_@24>d
//ps.addBatch();⑵ p{W
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} pY3/AO=
//int [] counts = ps.executeBatch();⑶ V9}\0joM
conn.commit(); dY0W=,X$7T
}catch(Exception e){ 1@ &J"*
e.printStackTrace(); n3&h1-
} finally{ .m8l\h^3
try{ jPZ+~:m+
if(ps!=null) { }fkdv6mz
ps.clearParameters(); 0 V]MAuD($
ps.close(); eN
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ps=null; ~MC5rOA
} [A{o"zY
}catch(SQLException e){} iHf):J?8
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DBUtils.closeConnection(conn); He4HIZ
} "nfi:A1
} ]+a~/
public long getLast(){ LEtGrA/%@b
return lastExecuteTime; ^z{Xd|{"
} yih|6sd$F
public void run(){ l/B+k
long now = System.currentTimeMillis(); fJ5mKN
if ((now - lastExecuteTime) > executeSep) { K;rgLj0m
//System.out.print("lastExecuteTime:"+lastExecuteTime); LJb=9tp~
//System.out.print(" now:"+now+"\n"); }1[s ,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); cpw=2vnD
lastExecuteTime=now; R2{]R&wtn0
executeUpdate(); i%<NKE;v7m
} 8rlf9m
else{ [*(1~PrlO,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -}j(_]t
} X)Tyxppf'
} Akc
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} (;05=DsO
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Hf1b&8&:K
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类写好了,下面是在JSP中如下调用。 <*^|Aj|#
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<% S *J{
CountBean cb=new CountBean(); g{sp<w0
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); pp1Kor
CountCache.add(cb); [PiMu,O[v
out.print(CountCache.list.size()+"<br>"); [Y.JC'F#
CountControl c=new CountControl(); ujBm"p_|
c.run(); a=y%+E'a'
out.print(CountCache.list.size()+"<br>"); D$H&^,?N
%>