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: qD"~5vtLqQ
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CountBean.java N1y,~Z
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/* 07(LLhk@d
* CountData.java $Sm iN'7;
* 96!2@c{
* Created on 2007年1月1日, 下午4:44 {<Y!'WL{
* rOUQg_y
* To change this template, choose Tools | Options and locate the template under F!I9)PSj
* the Source Creation and Management node. Right-click the template and choose tmoclK-
* Open. You can then make changes to the template in the Source Editor. xjxX4_
*/ if1)AE-
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package com.tot.count; w9x5 IRW k
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/** wB[
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* )g-0b@z!n
* @author t >64^nS
*/ _-v$fDrz
public class CountBean { %6V=G5+W
private String countType; B/~ubw
int countId; b?M. 0{"H
/** Creates a new instance of CountData */ BT -Y9j
public CountBean() {} /bC@^Y&}
public void setCountType(String countTypes){ =zp{ ^mC
this.countType=countTypes; |`I9K#w3
} ;'!h(H
public void setCountId(int countIds){ mxc^IRj
this.countId=countIds; _39VL
} E%f!SD
public String getCountType(){ !;k
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return countType; 3)^2X
} M|.ykA<D
public int getCountId(){ )4YtdAV
return countId; kZ^wc .
} WL\*g] K4
} [#:yOZt
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CountCache.java D_w<igu!3
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/* Pn}oSCo
* CountCache.java kRiZ6mn
* 2m&?t_W
* Created on 2007年1月1日, 下午5:01 l2LO,j}
* `|[UF^9
* To change this template, choose Tools | Options and locate the template under qyBo|AQ5
* the Source Creation and Management node. Right-click the template and choose w*4sT+
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* Open. You can then make changes to the template in the Source Editor. m?1AgsBR
*/ +ldgT"
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package com.tot.count; 4?x$O{D5?{
import java.util.*; <+`}:
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/** Hn?v/3
* 1~*JenV-
* @author dM5N1$1,
*/ jpfFJon)w
public class CountCache { !R$t>X
public static LinkedList list=new LinkedList(); O~F8lQ
/** Creates a new instance of CountCache */ e]l.m!,r
public CountCache() {} /gLi(Uw
public static void add(CountBean cb){ EMS$?"K
if(cb!=null){ kc"SUiy/
list.add(cb); onUF@3V
} ]1KF3$n0
} sHMZ'9b
} OQsF$%*
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CountControl.java *5S~@
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/* ^Hv4t
* CountThread.java E#+|.0*!s
* r(/+-
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* Created on 2007年1月1日, 下午4:57 l0{R`G,
* }JBLzk5|
* To change this template, choose Tools | Options and locate the template under ^y&sKO
* the Source Creation and Management node. Right-click the template and choose q{oppali
* Open. You can then make changes to the template in the Source Editor. W&0KO-}ot
*/ THDyb9_g
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package com.tot.count; %$SO9PY
import tot.db.DBUtils; %C(^v)"
import java.sql.*; Ln5g"g8gb%
/** AtW<e;!0te
* :/'oh]T|
* @author =GSe$f?
*/ %13V@'e9
public class CountControl{ )*n2,n
private static long lastExecuteTime=0;//上次更新时间 <;nhb
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 DS1_hbk
/** Creates a new instance of CountThread */ 16R0#Q/{+*
public CountControl() {} *.F4?i2D
public synchronized void executeUpdate(){ 'Q F@@ 48
Connection conn=null; '?MT"G
PreparedStatement ps=null; z1 P=P%F
try{ JE.s?k
conn = DBUtils.getConnection(); &x<y4ORH|
conn.setAutoCommit(false); %T'<vw0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); r;cILS|Xr
for(int i=0;i<CountCache.list.size();i++){ 2h5L#\H"
CountBean cb=(CountBean)CountCache.list.getFirst(); I&G"{Dl94
CountCache.list.removeFirst(); B(h%>mT[
ps.setInt(1, cb.getCountId()); w_]`)$9
ps.executeUpdate();⑴ X(*MHBd
//ps.addBatch();⑵ E|v9khN(].
} s'Wu \r'
//int [] counts = ps.executeBatch();⑶ ];8S<KiS~
conn.commit(); _[t:Vme}v
}catch(Exception e){ G"|`&r@
e.printStackTrace(); wY6m^g$h3
} finally{ kx31g,cf]w
try{ Ny2. C?2
if(ps!=null) { pa8R;A70Dl
ps.clearParameters(); N>Q~WXvV#
ps.close(); * faG0le
ps=null; -#<AbT
} zVyMmw\
}catch(SQLException e){} Q.Xs%{B
DBUtils.closeConnection(conn); VBv|7S
} !
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} Dlqvz|X/
public long getLast(){ Zb}U 4
return lastExecuteTime; ]wm<$+@
} [2\jQv\Y
public void run(){ 5DxNHEuS
long now = System.currentTimeMillis(); It:,8
if ((now - lastExecuteTime) > executeSep) { z,xGjSP
//System.out.print("lastExecuteTime:"+lastExecuteTime); o'J^kd`
//System.out.print(" now:"+now+"\n"); ;fe~PPT
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); DA_}pS"
lastExecuteTime=now; n4InZ!)
executeUpdate(); $q*hE&x
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} F_ -}GN%
else{ fR>"d<;T
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &t:~e" 5<
} "DvhAEM
} H7%q[O
} D=@bP B>
//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 e?_uJh"
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类写好了,下面是在JSP中如下调用。 YHzP/&0
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<% kX%vTl7F
CountBean cb=new CountBean(); pv8vW'G\E
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;a 6Z=LB
CountCache.add(cb); ek1<9"y
out.print(CountCache.list.size()+"<br>"); Y_nl9}&+C0
CountControl c=new CountControl(); |eI!wgQx
c.run(); ~J HEr48
out.print(CountCache.list.size()+"<br>"); ^cCNQS}r
%>