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: R,k[Kh
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CountBean.java > & lg
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/* ?f%DVK d
* CountData.java xsypIbN
* d4rJ?qw
* Created on 2007年1月1日, 下午4:44 `J;/=tf09
* #._6lESK
* To change this template, choose Tools | Options and locate the template under !t
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* the Source Creation and Management node. Right-click the template and choose nV6g]#~@
* Open. You can then make changes to the template in the Source Editor. 3t}o0Ai9
*/ ry<}DK<u
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package com.tot.count; J}` $WL:
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/** [/`Hz]R
* GA@Q:n8UuR
* @author 70l;**"4
*/ "r(pK@h
public class CountBean { Vste$V
private String countType; D
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int countId; / o3FK
/** Creates a new instance of CountData */ y8 u)Q
public CountBean() {} qSs^}eN
public void setCountType(String countTypes){ rcb/X`l=
this.countType=countTypes; rG'k<X~7
} ?z36mj"`o
public void setCountId(int countIds){ i /U{dzZ
this.countId=countIds; a5g{.:NfO
} $@!&ML
public String getCountType(){ ?^A:~" ~
return countType; ,lG wW8$R
} ?;kc%Rz
public int getCountId(){ =kkA
return countId; 0BZOr-i
} #~qp8
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} U@ QU8
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CountCache.java wOl-iN=
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/* +as\>"Cj+2
* CountCache.java fv7g93
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* Created on 2007年1月1日, 下午5:01 PX{~! j%n
* oN}j <6s
* To change this template, choose Tools | Options and locate the template under /hy!8c7
* the Source Creation and Management node. Right-click the template and choose dD2e"OIX
* Open. You can then make changes to the template in the Source Editor. dK`O,[}
*/ ?26[%%
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package com.tot.count; EJ|ZZYke!
import java.util.*; !ZcALtq
/** Cjb p-
* !ef)Ra-W
* @author V0&QEul
*/ X-^Oz@.>
public class CountCache { 8o!^ZOmU<
public static LinkedList list=new LinkedList(); y#W8] <dS"
/** Creates a new instance of CountCache */ :fQ*'m,
public CountCache() {} ~./u0E
public static void add(CountBean cb){ I z@x^s
if(cb!=null){ FnU;n
list.add(cb); nff ]Y$FB
} q\=[v
} 5~6y.S
} 9Qd'=JQl
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CountControl.java >R0j<:p :
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/* f
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* CountThread.java *wx^mB9
* +Rd{ ?)2~
* Created on 2007年1月1日, 下午4:57 E8 )*HOT_T
* 30-wTcG
* To change this template, choose Tools | Options and locate the template under fxa^SV
* the Source Creation and Management node. Right-click the template and choose /1GZN *I
* Open. You can then make changes to the template in the Source Editor. FA GVpO[
*/ U9OF0=g
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package com.tot.count; R-|]GqS}L
import tot.db.DBUtils; P"VLGa
import java.sql.*; 4r!40^:2
/** FNO
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* 7q1l9:VYE
* @author |pg5m*h
*/ xef7mx
public class CountControl{ ,4$J|^T&
private static long lastExecuteTime=0;//上次更新时间 CK#PxT?"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AYerz
/** Creates a new instance of CountThread */ &^>r<~]
public CountControl() {} QrA+W\=_`y
public synchronized void executeUpdate(){ 6u8fF|s
Connection conn=null; a
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PreparedStatement ps=null; Darkj>$\
try{
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conn = DBUtils.getConnection(); 7dW&|U
conn.setAutoCommit(false); ,~w)@.
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 06O
for(int i=0;i<CountCache.list.size();i++){ 0\;a:E.c
CountBean cb=(CountBean)CountCache.list.getFirst(); &"0[7zgYQz
CountCache.list.removeFirst(); )Jn80~U|1
ps.setInt(1, cb.getCountId()); Q)8t;Kx
ps.executeUpdate();⑴ 7 4UE-H)
//ps.addBatch();⑵ XcneH jpR
} $*ZHk0
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//int [] counts = ps.executeBatch();⑶ Re>e|$.T
conn.commit(); }_TdXY
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}catch(Exception e){ 8h2?Q
e.printStackTrace(); [b'fz
} finally{ KfS^sT
try{ } 4^UVdz
if(ps!=null) { EpMEA1=&
ps.clearParameters(); ~;` #{$/C&
ps.close(); 6dlPS{H#U
ps=null; zD|W3hL2&
} - d6>
}catch(SQLException e){} OkXOV
DBUtils.closeConnection(conn); \aozecpC`
} bp_@e0
} C I0^eaFs
public long getLast(){ Czn7,KE8X
return lastExecuteTime; 4v$AM8/o
} i{0_}"B
public void run(){ #a:C=GV;4
long now = System.currentTimeMillis(); N<%,3W_-_
if ((now - lastExecuteTime) > executeSep) { : Tl?yGF
//System.out.print("lastExecuteTime:"+lastExecuteTime); N<WFe5
//System.out.print(" now:"+now+"\n"); tDVdl^#
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Uk4">]oct
lastExecuteTime=now; 8&bj7w,K
executeUpdate(); .(ir2g
} ya=51~ by"
else{ I'hQbLlG
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); `$HO`d@0*R
} %cL:*D4oz
} I&c#U+-A'
} sjGZ
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//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 ualtIHXK)
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类写好了,下面是在JSP中如下调用。 f
;JSP
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<% i:72FVo
CountBean cb=new CountBean(); 8!fwXm
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,5,4 Qf7
CountCache.add(cb); Tc:`TE=2
out.print(CountCache.list.size()+"<br>"); AJmzg
CountControl c=new CountControl(); 5[k35c{
c.run(); \;<Y/sg
out.print(CountCache.list.size()+"<br>"); DSp@
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