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: K,*If Hi6[
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CountBean.java )EG-xo@X
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/* V.[b${
* CountData.java }J=z O8OL
* P2)g%$ME
* Created on 2007年1月1日, 下午4:44 vw` '9~
* jw]IpGTt
* To change this template, choose Tools | Options and locate the template under 'eoI~*}3WQ
* the Source Creation and Management node. Right-click the template and choose +>v{#A_u
* Open. You can then make changes to the template in the Source Editor. *1}vn%wvn
*/ b*a}~1
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package com.tot.count; !v 3wl0
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/** td+[Na0d
* %$!EjyH9
* @author N?Ss/by8Sg
*/ S[uHPYhlA
public class CountBean { Vs[!WJ
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private String countType; W/;qMP1"-
int countId; g? \pH:|79
/** Creates a new instance of CountData */ ?/ s=E+
public CountBean() {} upH%-)%'
public void setCountType(String countTypes){ H
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this.countType=countTypes; vGPaW YV
} n1c Q#u
public void setCountId(int countIds){ ]9pcDZB
this.countId=countIds; AwL;-|X
} hO:X\:G
public String getCountType(){ qsL6*(S(r
return countType; B6vmBmN
} *'(dcy9
public int getCountId(){ wwmODw<tT
return countId; E0S[TEDa]
} s/'gl
} yc 5n
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CountCache.java `o*g2fW!
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/* ^q$vyY
* CountCache.java `0Q:d'
* +e"}"]n
* Created on 2007年1月1日, 下午5:01 c#;LH5KI
* ?-'Q-\j
* To change this template, choose Tools | Options and locate the template under _.06^5o
* the Source Creation and Management node. Right-click the template and choose M+^K,
* Open. You can then make changes to the template in the Source Editor. ^NLKX5Q
*/ [l5"'{x
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package com.tot.count; J0p,P.G
import java.util.*; Pjb9FCA'
/** |2 wff?
* W{m0z+N[B
* @author O x$|ZEh
*/ @7^#_772
public class CountCache { L
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public static LinkedList list=new LinkedList(); %#QFu/l
/** Creates a new instance of CountCache */ sqZHk+<%
public CountCache() {} S s`0;D1
public static void add(CountBean cb){ LMG\jc?,
if(cb!=null){ {M~!?#<K
list.add(cb); hy )RV=X
} }C&c=3V
} wbS++cF<
} .RWBn~b#I
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CountControl.java >aWJ+
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/* `(a^=e5
* CountThread.java )eV40l$
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* #dfW1@m
* Created on 2007年1月1日, 下午4:57 XbOL/6V ^[
* +{w&ksk
* To change this template, choose Tools | Options and locate the template under 8say"Qz
* the Source Creation and Management node. Right-click the template and choose Cp* n2
* Open. You can then make changes to the template in the Source Editor. 5k(#kyP
*/ 0Yjy
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package com.tot.count; M#>GU<4"
import tot.db.DBUtils; KE3v3g<
import java.sql.*; gPi_+-@
/** Vi|jkyC8
* t;1NzI$^
* @author ~<U3KB
*/ T7Ac4LA
public class CountControl{ p{J_d,JH
private static long lastExecuteTime=0;//上次更新时间 ?f`-&c;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @6!JW(,]\
/** Creates a new instance of CountThread */ e`rY]X
public CountControl() {} 31C]TdJ
public synchronized void executeUpdate(){ ?:nZv<
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Connection conn=null; 0R]CI
PreparedStatement ps=null; !%X`c94
try{ 7e<Q{aB
conn = DBUtils.getConnection(); eQx"nl3U%
conn.setAutoCommit(false); $(R)
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8TPm[r]
for(int i=0;i<CountCache.list.size();i++){ h'x~"k1
CountBean cb=(CountBean)CountCache.list.getFirst(); TH!8G,(w
CountCache.list.removeFirst(); j#f&!&G5<&
ps.setInt(1, cb.getCountId()); iL, XBoE
ps.executeUpdate();⑴ J":9
//ps.addBatch();⑵ DV\ei")
} (O2HB-<rY
//int [] counts = ps.executeBatch();⑶ !y`e,(E
conn.commit(); c1J)yv1y
}catch(Exception e){ b2e a0
e.printStackTrace(); m[j3s=Gr
} finally{ d6EY'*0
try{ ..!-)q'?
if(ps!=null) { K, 5ax@
ps.clearParameters(); @t8kN6.
ps.close(); ;x^,t@ xge
ps=null; +[/r^C
} eF^"{a3b
}catch(SQLException e){} b,R'T+4[
DBUtils.closeConnection(conn); \]A;EwC4C
} J*!:ar
} -0da"AB
public long getLast(){ _D9@<+MS*
return lastExecuteTime; DS}rFU
} Gc!8v}[7J
public void run(){ j(C
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long now = System.currentTimeMillis(); @:9fS
if ((now - lastExecuteTime) > executeSep) { 9[{>JRm.
//System.out.print("lastExecuteTime:"+lastExecuteTime); lp-Zx[#`}C
//System.out.print(" now:"+now+"\n"); YG~ o
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); n qLAby_
lastExecuteTime=now; 1bZiPG{
executeUpdate(); rHgdvDc
} BDkBYhz;7
else{ !u{"] T:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); SWjQ.aM
} .q`H`(QM
} YB
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} p?$G>nkdq
//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 tNuC xb-
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类写好了,下面是在JSP中如下调用。 U+PCvl=x
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<% M2E87w
CountBean cb=new CountBean(); kq%gY
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 4m~7 ~- h
CountCache.add(cb); fb"J Bc}X
out.print(CountCache.list.size()+"<br>"); *rn]/w8ZW
CountControl c=new CountControl(); noh|/sPMD
c.run(); [Ba2b: l6v
out.print(CountCache.list.size()+"<br>"); qE`:b0FT
%>