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: dPgA~~
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CountBean.java QEx&AT
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/* 6jl{^dI
* CountData.java pMp@W`i^6
* Tm~jYgJ
* Created on 2007年1月1日, 下午4:44 pBQ[lPCY/
* F1`mq2^@
* To change this template, choose Tools | Options and locate the template under _F8-4
* the Source Creation and Management node. Right-click the template and choose :b#5cMUe
* Open. You can then make changes to the template in the Source Editor. ~n/:a
*/ ~ r$I&8
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package com.tot.count; % %2~%FVb
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/** 15DlD`QV
* {>brue*)
* @author y>RqA*J
*/ \D[~54
public class CountBean { L;KLmxy#
private String countType; Ww{-(Ktx
int countId; -r0oO~KT
/** Creates a new instance of CountData */ 1;>RK
public CountBean() {} BTE&7/i21
public void setCountType(String countTypes){ SC2g5i`
this.countType=countTypes; a<V
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} 52.hJNq#L
public void setCountId(int countIds){ VrFI5_M/
this.countId=countIds; )9!ZkZbv_m
} a$6pA@7}
public String getCountType(){ Io_7
return countType; Z \-
} %g4)f9>
public int getCountId(){ Q?9eu%G6I
return countId; _&xkj8O
} fAvB!e
} y|wR)\
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CountCache.java `7',RUj|D
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/* N=:xyv
* CountCache.java u)ZZ/|
* #mO.[IuD
* Created on 2007年1月1日, 下午5:01 vF@.BM>
* 9x9E+DG#(
* To change this template, choose Tools | Options and locate the template under +Pn`AV1
* the Source Creation and Management node. Right-click the template and choose Gs}lw'pK
* Open. You can then make changes to the template in the Source Editor. jg3['hTJT
*/ %,) Xi
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package com.tot.count; 9Mv4=k^7|4
import java.util.*; q{)Q ?E
/** %E2C4UbY
* 2Xfy?U
* @author <^8OYnp
*/ 'wTJX>
public class CountCache { WF<*rl
public static LinkedList list=new LinkedList(); +Nka,C^O"
/** Creates a new instance of CountCache */ sM%.=~AN
public CountCache() {} cACnBgLl
public static void add(CountBean cb){ zU};|Zw
if(cb!=null){ V0:db
list.add(cb); u\UI6/
} jTY{MY Jh
} 6[>Z y)P
} E__A1j*gd
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CountControl.java hM`*-+Zb
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/* !myF_cv}'
* CountThread.java `3F/7$q_
* 9M-/{D^+<
* Created on 2007年1月1日, 下午4:57 sk`RaDq@;
* rB5+~
K@
* To change this template, choose Tools | Options and locate the template under -QP1Se*#
* the Source Creation and Management node. Right-click the template and choose u+e.{Z!
* Open. You can then make changes to the template in the Source Editor. )$I"LyK)
*/ ~bJ*LM?wOP
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package com.tot.count; R
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import tot.db.DBUtils; 885
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import java.sql.*; CB?H`R pC.
/** (fWQ?6[
* y]f| U-f:~
* @author px_%5^zRQ
*/ BRMR>
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public class CountControl{ *r]#jY4qx
private static long lastExecuteTime=0;//上次更新时间 ~w RozV
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Z7R+'OC
/** Creates a new instance of CountThread */ &,`P%a&k
public CountControl() {} Aaix?
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public synchronized void executeUpdate(){ OAz-w
Connection conn=null; h%@#jvh?4
PreparedStatement ps=null; vweD{\b
try{ n?A;'\cK
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); R0mWVgoz
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (tP^F)}e5
for(int i=0;i<CountCache.list.size();i++){ u8@>ThPD
CountBean cb=(CountBean)CountCache.list.getFirst(); -n'%MT=Cd
CountCache.list.removeFirst(); sQe>LNp,G
ps.setInt(1, cb.getCountId()); 5=Y\d,SS"
ps.executeUpdate();⑴ bDPT1A`F
//ps.addBatch();⑵ gs77")K&
} ;rH@>VrR
//int [] counts = ps.executeBatch();⑶ pF"IDC
conn.commit(); O8ZHIs
}catch(Exception e){ tI(co5 W
e.printStackTrace(); .{W)E
} finally{ c^8y/wfok
try{ n-_-;TYH
if(ps!=null) { ^KMZB
ps.clearParameters(); [t`QV2um
ps.close(); _/!IjB:(70
ps=null; 3^zOG2
} Au/n|15->C
}catch(SQLException e){} 1%6}m`3
DBUtils.closeConnection(conn); VN8ao0^d;d
} sxLq'3(
} ZK]C!8\2|
public long getLast(){ |bz,cvlP
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return lastExecuteTime; ]={{$}8.
} +<H)DPG<
public void run(){ P1ab2D
long now = System.currentTimeMillis(); "L" 6jT
if ((now - lastExecuteTime) > executeSep) { W7"ks(
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3J}bI{3
//System.out.print(" now:"+now+"\n"); up7]Yy;o=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); L1k_AC1.M
lastExecuteTime=now; <&rvv4*H
executeUpdate(); YvK8;<k@-?
} ?79ABm
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else{ )y:~T\g
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); VscEdtkd
} uIvE~<
} f z8eL:i:
} O(PG"c
//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 u-7/4Y)c
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类写好了,下面是在JSP中如下调用。 L%JmdY;
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<% j>Htaa
CountBean cb=new CountBean(); .Eg>)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @vaK-&|#$
CountCache.add(cb); 3B|o
out.print(CountCache.list.size()+"<br>"); T!)v9L
CountControl c=new CountControl(); `:A`%Fg8<
c.run(); FXOA1VEg
out.print(CountCache.list.size()+"<br>"); l7P~_X_)"
%>