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: $;1#To
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CountBean.java 8$")%_1]
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/* j/R[<47
* CountData.java DK$X2B"c V
* RHmgD;7`
* Created on 2007年1月1日, 下午4:44 >"|B9Woc
* %SX|o-B~.o
* To change this template, choose Tools | Options and locate the template under iX0i2ek
* the Source Creation and Management node. Right-click the template and choose h]Wr [v
* Open. You can then make changes to the template in the Source Editor. 4lr(,nPRD
*/ I KqQ>Z-q~
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package com.tot.count; lpQSup
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/** J3e96t~u
* N*"p|yhd]
* @author '10oK {m$
*/ j}%ja_9S
public class CountBean { wb]%m1H`:
private String countType; cv?06x{
int countId; q1z"-~i)E
/** Creates a new instance of CountData */ w$+&3t
public CountBean() {} a6D &/8
public void setCountType(String countTypes){ 5~r33L%
this.countType=countTypes; MLoYnR^
} G}:w@}h/
public void setCountId(int countIds){ p~SClaR3H
this.countId=countIds; wfNk=)^$
} RX>xB
public String getCountType(){ dYG,_ji
return countType; v'U{/ ,x
} % 5m/
public int getCountId(){ qAAX;N
return countId; z>XrU>}
} =T-&j60
} |uX,5Q#6
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CountCache.java ,I7E[LU
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/* >OL 3H$F
* CountCache.java /q<__N
* &:/hrighH
* Created on 2007年1月1日, 下午5:01 TV<'8L
* R%{a1r>9h
* To change this template, choose Tools | Options and locate the template under Rtb7|
* the Source Creation and Management node. Right-click the template and choose K@sV\"U(*E
* Open. You can then make changes to the template in the Source Editor. ,24p%KJ*X
*/ }@;ep&b*
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package com.tot.count; x,rlrxI
import java.util.*; >64P6P;S
/** uEktQ_u[
* +@94;me
* @author 8"U. Hnu
*/ Fgp]l2*
public class CountCache { mp=z
public static LinkedList list=new LinkedList(); !D@ZYK;
/** Creates a new instance of CountCache */ i&5XF
public CountCache() {} H=g`hF]`
public static void add(CountBean cb){ G+%zn|
if(cb!=null){ M@`;JjtSA
list.add(cb); pk^K:Xs}
} CS@FYO
} {_`^R>"\&w
} 23c 8
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CountControl.java ;LG#.~f
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/* uW30ep'
* CountThread.java .$qnZWcgG
* <R''oEf9
* Created on 2007年1月1日, 下午4:57 F$ #U5}Q
* 1`(tf6op
* To change this template, choose Tools | Options and locate the template under vd[}Gd
* the Source Creation and Management node. Right-click the template and choose ]~aF2LJ_q
* Open. You can then make changes to the template in the Source Editor. 8vMG5#U[
*/ -*$HddD
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package com.tot.count; UJM1VAJ0
import tot.db.DBUtils; V8rx#H~
import java.sql.*; LS7, a|
/** n\xX},
* y0#u9t"Z;
* @author oXb;w@:
*/ Fx;QU)1l3
public class CountControl{ )6q,>whI]
private static long lastExecuteTime=0;//上次更新时间 #
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 YE|SKx@
/** Creates a new instance of CountThread */ Tw""}|] g
public CountControl() {} '
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public synchronized void executeUpdate(){ g]4(g<:O
Connection conn=null; >Db;yC&
PreparedStatement ps=null; Ov-icDMm
try{ OW3sS+y
conn = DBUtils.getConnection(); w2
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conn.setAutoCommit(false); \HKxh:F'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); YL]Z<%aKt
for(int i=0;i<CountCache.list.size();i++){ |G?htZF
CountBean cb=(CountBean)CountCache.list.getFirst(); Y8m1M-#w
CountCache.list.removeFirst(); .#rJ+.2
ps.setInt(1, cb.getCountId()); `(YxI
ps.executeUpdate();⑴ umiBj)r
//ps.addBatch();⑵ E%rk[wI
} ;$smH=I
//int [] counts = ps.executeBatch();⑶ d8[J@M53|T
conn.commit(); L1cI`9
}catch(Exception e){ ZUoxMm
e.printStackTrace(); q(`/Vo4g(
} finally{ rEB@$C^
try{ P(+&OoY2
if(ps!=null) { RloK,bg
ps.clearParameters(); n?- })
ps.close(); {so`/EWa
ps=null; ~]nSSD)\
} / c AUl
}catch(SQLException e){} DNr@u/>vB
DBUtils.closeConnection(conn); wB!Nc Y\p
} WU71/PYm`
} 1JztFix
public long getLast(){ }+C2I
return lastExecuteTime; \l9qt5rS
} 0:9.;x9_
public void run(){ @GdbTd
long now = System.currentTimeMillis(); m 8aITd8
if ((now - lastExecuteTime) > executeSep) { 3NqN\5B:
//System.out.print("lastExecuteTime:"+lastExecuteTime); I'uSp-Sfy
//System.out.print(" now:"+now+"\n"); mt,OniU= Q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 0=AVW`J
lastExecuteTime=now; BT}!W`
executeUpdate(); 3E!|<q$z
} 1Cv-
else{ ?u "
4@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); mF,Y?ax
} zi]\<?\X
} &Low/Y'.jJ
} s'%R
//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 8W,Jh8N6
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类写好了,下面是在JSP中如下调用。 P:k>aHnW
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<% X voo=
CountBean cb=new CountBean(); vgfcCcZ_iZ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); D-5VC9{
CountCache.add(cb); 0w&27wW
out.print(CountCache.list.size()+"<br>"); ki?S~'a
CountControl c=new CountControl(); d$ x"/A]<
c.run(); kXi6lh
out.print(CountCache.list.size()+"<br>"); B?'#4J
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