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: j{U#g8
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CountBean.java ^#6"d+lp
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/* |b
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* CountData.java 4qd =]i
* -\6";_Y
* Created on 2007年1月1日, 下午4:44 |UudP?E
* O#}d!}SIp
* To change this template, choose Tools | Options and locate the template under [N35.O6P6u
* the Source Creation and Management node. Right-click the template and choose 5s5GBJ?
* Open. You can then make changes to the template in the Source Editor. gI~4A,
*/ AQUl:0!
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package com.tot.count; wgN)*dpuI
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/** BzVF!<!
* 4R c_C0O
* @author A^m]DSFOO
*/ ;^[VqFpeS
public class CountBean { UQ7E7yY#
private String countType; vb&1 S
int countId; =XRTeIZ
/** Creates a new instance of CountData */ TO,XN\{y
public CountBean() {} o@6hlLr
public void setCountType(String countTypes){ gv6}GE
this.countType=countTypes; Zb \E!>V
} IIZu&iZo\
public void setCountId(int countIds){ wsfN \6e
this.countId=countIds; zL^`r)H
} fGwRv%$^
public String getCountType(){ ~BUzyc%
return countType; he
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} z1K}] z%
public int getCountId(){ 7EfLd+
return countId; =6sA49~M
} {vp|f~}zTw
} A`#/:O4|f
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CountCache.java b0PQ;?R#V
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/* `rwzCwA1
* CountCache.java 5xS
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* `wMHjcUP
* Created on 2007年1月1日, 下午5:01 ytmFe !
* !1X^lFf;~
* To change this template, choose Tools | Options and locate the template under 5PcN$r"P
* the Source Creation and Management node. Right-click the template and choose KTmduf7DL
* Open. You can then make changes to the template in the Source Editor. Ar;uq7c,G
*/ 6Mh;ld@
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package com.tot.count; sy\w ^]
import java.util.*; wU"0@^k]<
/** 96VJE,^h
* ~!Ar`=
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* @author o 94]:$=~
*/ brdfjE8
public class CountCache { ,GU|3
public static LinkedList list=new LinkedList(); un&Z'
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/** Creates a new instance of CountCache */ (
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public CountCache() {} 'XbrO|%
public static void add(CountBean cb){ E7CeE6U
if(cb!=null){ I6.!0.G
list.add(cb); (V06cb*42[
} I7S#vIMXR.
} .5tE, (<?
} Uo~-^w}
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CountControl.java mY'c<>6t
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/* US.7:S-r"
* CountThread.java q^I/
* z_ 01*O
* Created on 2007年1月1日, 下午4:57 CyWMr/'
* $:4*?8K2
* To change this template, choose Tools | Options and locate the template under {hNvCk
* the Source Creation and Management node. Right-click the template and choose (C&Lpt_
* Open. You can then make changes to the template in the Source Editor. %XQ!>BeE
*/ QAk.~ob
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package com.tot.count; 1KI,/ H"SY
import tot.db.DBUtils; ~{xm(p
import java.sql.*; Dp8`O4YC
/** p'fD:M:
* J%
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* @author @:ojt$
*/ nZtP!^#
public class CountControl{ b@>MA
private static long lastExecuteTime=0;//上次更新时间 5;alq]m7
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 +n>_NVe
/** Creates a new instance of CountThread */ !D \u2h
public CountControl() {} K:cZq3F
public synchronized void executeUpdate(){ ^z^zsNx
Connection conn=null;
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PreparedStatement ps=null; 7gx
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try{ $Ith8p~
conn = DBUtils.getConnection(); P@xb
conn.setAutoCommit(false); \\D(St
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .^F(&c*['
for(int i=0;i<CountCache.list.size();i++){ ?RMOy$L
CountBean cb=(CountBean)CountCache.list.getFirst(); HT%
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CountCache.list.removeFirst(); nF)XZB0F
ps.setInt(1, cb.getCountId()); B(zcoWQ*B
ps.executeUpdate();⑴ GdlzpBl
//ps.addBatch();⑵ h,palP6^
} oRALhaI
//int [] counts = ps.executeBatch();⑶ Z=|NoDZ
conn.commit(); ?6#F9\
}catch(Exception e){ ~CRd0T[^
e.printStackTrace(); PL}c1Ud
} finally{ W74Y.zQ
try{ }}Kjb
if(ps!=null) { P\nz;}nv
ps.clearParameters(); h;lg^zlTb
ps.close(); YTk"'q-
ps=null; W[R^5{k`
} [d3i_^\
}catch(SQLException e){} nl\l7/}6
DBUtils.closeConnection(conn); je[1>\3W
} e*Gt%'
} GI
;
public long getLast(){ xis],.N
return lastExecuteTime; AY
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} iL6Yk @
public void run(){ ,P.yl~'Al
long now = System.currentTimeMillis(); $-Yq?:
if ((now - lastExecuteTime) > executeSep) { Af`qe+0E
//System.out.print("lastExecuteTime:"+lastExecuteTime); 6`JY:~V"
//System.out.print(" now:"+now+"\n"); c2o.H!>
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); -yJ%G1R
lastExecuteTime=now; "N*bV
executeUpdate(); dU"ca|u
} Z6S?xfhr'{
else{ (]}52%~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >69- [#P!
} 6 *GR_sMm
} Ks>l=5~v|
} }NgevsV>;
//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 kHhxR;ymA7
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类写好了,下面是在JSP中如下调用。 n]Z() "D
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<% v&]k8Hc-
CountBean cb=new CountBean(); ~5@bWJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); wa f)S=
CountCache.add(cb); _Xe"+
out.print(CountCache.list.size()+"<br>"); mFa%d8Y
CountControl c=new CountControl(); \kS:u}Ip!
c.run(); oz[Mt
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out.print(CountCache.list.size()+"<br>"); H-g
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%>