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: ;e *!S}C,
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CountBean.java zrb}_
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/*
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* CountData.java W'TZ%K) I
* f-Z/tfC
* Created on 2007年1月1日, 下午4:44 S,he6zS
* t{{QE:/
* To change this template, choose Tools | Options and locate the template under b\2
ds,
* the Source Creation and Management node. Right-click the template and choose 5$k:t
* Open. You can then make changes to the template in the Source Editor. [4f{w%~^
*/ j\M?~=*w
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package com.tot.count; L!xi
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/** iXjM.G
* ?Ir:g=RP*
* @author ;4\;mmLVk
*/ tR$NRMZ.
public class CountBean { i/Zd8+.n$
private String countType; 7%M_'P4 V
int countId; 3Y$GsN4ln
/** Creates a new instance of CountData */ Q$"D]!G
public CountBean() {} ~t~|"u"P
public void setCountType(String countTypes){ ;2QP7PrSY
this.countType=countTypes; T>W,'H
} ]Y&VT7+Z
public void setCountId(int countIds){ ;$g?T~v7
this.countId=countIds; V'gh6`v
} 5{,<j\#L
public String getCountType(){ 9pfIzs
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return countType; 8quaXVj^a
} Z%UP6%
public int getCountId(){ 'I;zJ`Trd
return countId; $XH^~i;
} OjA,]Gv6
} Q~9^{sHZjP
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CountCache.java C3g_!dUs
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/* ;O,jUiQ
* CountCache.java hhvyf^o
* 4*;MJ[|
* Created on 2007年1月1日, 下午5:01 K|=A:
* q)
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* To change this template, choose Tools | Options and locate the template under !&E-}}<
* the Source Creation and Management node. Right-click the template and choose W(p_.p"
* Open. You can then make changes to the template in the Source Editor. Ow,b^|
*/ 8z\xrY
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package com.tot.count; +=)+'q]S
import java.util.*; jebx40TA3
/** qH_Dc=~la
* "m>81-0
* @author Vxt+]5X
*/ BZ^}J!Q'*
public class CountCache { oXgcc*j
public static LinkedList list=new LinkedList(); !;'=iNOYR
/** Creates a new instance of CountCache */ d0>
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public CountCache() {} #g!.T g'
public static void add(CountBean cb){ 2
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if(cb!=null){ _q^E,P
list.add(cb); hi[pVk~B)
} <~=Vg
} a8Wwq?@
} xgtR6E^k
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CountControl.java -UT}/:a
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/* ;dhQN}7
* CountThread.java &%Tj/ Qx
* V(*(F7+
* Created on 2007年1月1日, 下午4:57 cB&:z)i4
* zbPqYhJzA
* To change this template, choose Tools | Options and locate the template under 2:ylv<\$
* the Source Creation and Management node. Right-click the template and choose \73ch
* Open. You can then make changes to the template in the Source Editor. apxph2yvS
*/ u]@['7
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package com.tot.count; )!T/3|C
import tot.db.DBUtils; Xn
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import java.sql.*; >(RkZ}z
/** / XIhj
* +ck}l2
* @author FN73+-:n:j
*/ i}?>g -(
public class CountControl{ Y<8vw
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private static long lastExecuteTime=0;//上次更新时间 /a o5FL
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 U/BR*Zn]*
/** Creates a new instance of CountThread */ Tm?# M&'
public CountControl() {} {(}By/_
public synchronized void executeUpdate(){ Z/J y'$x
Connection conn=null; yV(\R
PreparedStatement ps=null; ?bu>r=oIO]
try{ :~^(g$Z
conn = DBUtils.getConnection(); L/^I*p,
conn.setAutoCommit(false); ?z
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >o,TZc\
for(int i=0;i<CountCache.list.size();i++){ E4xa[iZ
CountBean cb=(CountBean)CountCache.list.getFirst(); !f6(Zho
CountCache.list.removeFirst(); PUX;I0Cf
ps.setInt(1, cb.getCountId()); Y
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ps.executeUpdate();⑴ /u+e0BHo
//ps.addBatch();⑵ n'w.;
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} PFK
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//int [] counts = ps.executeBatch();⑶ WuW^GC{7
conn.commit(); ;*&-C9b
}catch(Exception e){ Yz<1
wt7;
e.printStackTrace(); @s^-.z
} finally{ RpYERAgT
try{ cCc(fF*^
if(ps!=null) { )\^-2[;
ps.clearParameters(); pD]OT-8
ps.close(); X\F|Tk3_
ps=null; 5/z/>D;
} =nHgDrA_
}catch(SQLException e){} gPc=2
DBUtils.closeConnection(conn); t&DEb_"De
} jF*j0PkNdb
} 29q _BR *:
public long getLast(){ ~F7gP{r
return lastExecuteTime; ^G-@06 /!
} sn>~O4"
public void run(){ Ecx<OTo
long now = System.currentTimeMillis(); WMP,\=6k0
if ((now - lastExecuteTime) > executeSep) { ,6W>can
//System.out.print("lastExecuteTime:"+lastExecuteTime); S 6,.FYH
//System.out.print(" now:"+now+"\n"); B?o7e<l[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Xb,3Dvf
lastExecuteTime=now; BFW&2
executeUpdate(); GvlS%
} OK
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else{ 76` .Y
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,,|^%Ct']
} ei5~&
} 4nz 35BLr
} z&^&K}
//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 YT8F#t8
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类写好了,下面是在JSP中如下调用。 sUm'
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<% uUw5l})%Fi
CountBean cb=new CountBean(); &
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Nl1Do:PY
CountCache.add(cb); D7qOZlX16
out.print(CountCache.list.size()+"<br>"); .XhrCiZ
CountControl c=new CountControl(); /JU.?M35
c.run(); *k>n<p3dd
out.print(CountCache.list.size()+"<br>"); <_KIK
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