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: oupJJDpP
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CountBean.java "n{9- VEmN
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/* P$p@5 hl
* CountData.java +M44XhT
* %B#hb<7}
* Created on 2007年1月1日, 下午4:44 OJMvn'y
* wrH7 pd
* To change this template, choose Tools | Options and locate the template under -M"IVyy@
* the Source Creation and Management node. Right-click the template and choose a`7%A H)
* Open. You can then make changes to the template in the Source Editor. g~~m'^
*/ E^b
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package com.tot.count; yB-.sGu
n=f`AmF;
/** >$2E1HW.
* |'ZN!2u
* @author _ymJ~MK
*/ IYuyj(/!
public class CountBean { |n+#1_t%
private String countType; |.1qy,|!X
int countId; 98BYtxa
/** Creates a new instance of CountData */ $GQphXb$
public CountBean() {} .W!tveX8-
public void setCountType(String countTypes){ uVN.=
this.countType=countTypes; >HE,'
} 4Z*|Dsw
public void setCountId(int countIds){ ,+~2&>wj
this.countId=countIds; @Ppo &>
} N g58/}zO
public String getCountType(){ O
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return countType; |kId8WtA
} ;!'qtw"CB
public int getCountId(){ m'd^?Qc
return countId; <\h*Zy
} 1+R:3(AC
} GA.BI"l
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CountCache.java V?=TVI*k
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/* >Cvjs
* CountCache.java llNXQlP\B
* 1XG$ z@NN
* Created on 2007年1月1日, 下午5:01 >W'j9+Va
* GOGt?iw*<
* To change this template, choose Tools | Options and locate the template under >&BrCu[u
* the Source Creation and Management node. Right-click the template and choose !~kEtC
* Open. You can then make changes to the template in the Source Editor. zEy&4Kl{+
*/ _Aa[?2 O
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package com.tot.count; QO@6VY@
import java.util.*; for{
/** sN-oEqS
* ]5N zK=2{
* @author |B
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*/ K${}r0
public class CountCache { *MI)]S
public static LinkedList list=new LinkedList(); w}d}hI
/** Creates a new instance of CountCache */ N*f^Z#B]
public CountCache() {} c)03Ms4
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public static void add(CountBean cb){ _D-5}a"
if(cb!=null){ BH5w@
list.add(cb); ^1.7Juvb
} >&1um5K
} Pw= 3PvkL
} b{BaQ>.(`
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CountControl.java ;,dkJ7M
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/* Mm.Ql
* CountThread.java %]#VdS|N
* AeaPK
* Created on 2007年1月1日, 下午4:57 Evkt_vvf
* rCE;'? Y
* To change this template, choose Tools | Options and locate the template under *qG$19b
* the Source Creation and Management node. Right-click the template and choose -?5$ PH
* Open. You can then make changes to the template in the Source Editor. `dO}L
*/ ".E5t@ }?m
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package com.tot.count; n26>>N
import tot.db.DBUtils; ;b1wk^,Hw~
import java.sql.*; gH'_ymT=
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/** o!utZmk$
* 6|^0_6_
* @author xZyeX34{M;
*/ /$Z
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public class CountControl{ |Ytg
private static long lastExecuteTime=0;//上次更新时间 6b<+8w
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 C3)|<E
/** Creates a new instance of CountThread */ "XhOsMJ
public CountControl() {} *> KHRR<N
public synchronized void executeUpdate(){ gQ>2!Qc a-
Connection conn=null; tOM(U-7Z&
PreparedStatement ps=null; 5>P7]?U.]
try{ wyzOcx>M
conn = DBUtils.getConnection(); ]n5"Z,K
conn.setAutoCommit(false); ]^ #`j
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); zP&q7 t;>
for(int i=0;i<CountCache.list.size();i++){ ZBJ3 VK
CountBean cb=(CountBean)CountCache.list.getFirst(); -w ~(3(
CountCache.list.removeFirst(); Q&PB]D{
ps.setInt(1, cb.getCountId()); b_=8!Q.:
ps.executeUpdate();⑴ 87<9V.s2
//ps.addBatch();⑵ 5oJ Dux }
} ^dfx~C
//int [] counts = ps.executeBatch();⑶ G?/c/r G
conn.commit(); xr.XU'
}catch(Exception e){ ~ezCu_
e.printStackTrace(); qm'b'!gq~
} finally{ B+Z13;}B
try{ 7)J6/('
if(ps!=null) { {a@>6)
ps.clearParameters(); q{E"pyt36R
ps.close(); `
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ps=null; `hzrfum4
} Sl>>SP
}catch(SQLException e){} Us-A+)r*!
DBUtils.closeConnection(conn); Q]rqD83((
} ,H39V+Y*
} [(|v`qMv/g
public long getLast(){
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return lastExecuteTime; P'tMu6+)
} *d>vR1
public void run(){ eh<rRx"[
long now = System.currentTimeMillis(); ]*;F. pZ
if ((now - lastExecuteTime) > executeSep) { Go <'
//System.out.print("lastExecuteTime:"+lastExecuteTime); +9[SVw8
//System.out.print(" now:"+now+"\n"); '9J*6uXf.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6^E`Sa!s
lastExecuteTime=now; o@/xPo|
executeUpdate(); w<t,j~ Pr#
} DMd ,8W7a
else{ *Hs*,}MS
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -=)-s m'
} 2+'|kt2
} \A<v=VM|
} //.>>-~1m
//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-EhPAB@
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类写好了,下面是在JSP中如下调用。 0pN{y}x,
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<% 3SNL5
CountBean cb=new CountBean(); a2yE:16o6
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); eN/G i<
CountCache.add(cb); OVR?*"N_
out.print(CountCache.list.size()+"<br>"); mW4%2fD[
CountControl c=new CountControl(); m<: IFx#
c.run(); _ 08];M|
out.print(CountCache.list.size()+"<br>"); 2a `J%A
%>