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: a8aqcDs>O
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CountBean.java xyz86r ^u
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/* 7Z3qaXPH
* CountData.java :|3C-+[
* <);u]0
* Created on 2007年1月1日, 下午4:44 Ec
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* )yZE>>3-
* To change this template, choose Tools | Options and locate the template under QjU"|$
* the Source Creation and Management node. Right-click the template and choose >@uYleD(
* Open. You can then make changes to the template in the Source Editor. ]#.# ]}=
*/ B4ze$#
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package com.tot.count; qJj5J;k
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/** EtGr&\,
* fZgU@!z
* @author ?0Zw ^a
*/ l}/UriZ0
public class CountBean { _Y {g5t
private String countType; /WVMT]T6^,
int countId; B=|sLs`I
/** Creates a new instance of CountData */ 'WCTjTob/
public CountBean() {}
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public void setCountType(String countTypes){ >.4Sx~VH2
this.countType=countTypes; kzXW<V9
} R FiR)G ,
public void setCountId(int countIds){ |-D.
this.countId=countIds; 0fU>L^P_?
} MsQS{ok+
public String getCountType(){ 5GkM7Zu!{j
return countType; W:J00rsv=`
} MJ08@xGa
public int getCountId(){ xpwzz O*U
return countId; cTp+M L
} ^XVa!s,d
} K?
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CountCache.java %xz02$k
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/* h+@t8Q;gGw
* CountCache.java \gpKQt0
* |\t_I~de
* Created on 2007年1月1日, 下午5:01 0=&]!WRT
* l/LUwDI{
* To change this template, choose Tools | Options and locate the template under H#E0S>Jw|
* the Source Creation and Management node. Right-click the template and choose Nl _Jp:8s
* Open. You can then make changes to the template in the Source Editor. lc7]=,qyF
*/ *
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} _z~:{Y
package com.tot.count; 6:pN?|=6X
import java.util.*; Y~!@
/** v%^H9aK_
* `( Gk_VAa
* @author yK^k*)2N
*/ z16++LKmM
public class CountCache { [f}1wZ*
public static LinkedList list=new LinkedList(); 04t_
/** Creates a new instance of CountCache */ [&:oS35O
public CountCache() {} n>UvRn.7kz
public static void add(CountBean cb){ 7Wu2gky3
if(cb!=null){ =@>&kU%$&
list.add(cb); w?q"%F;/
} PYe>`X?
} f9$q.a*
} IYPLitT
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CountControl.java RI=B(0A
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/* l M$7/
* CountThread.java FCPbp!q6
* Jo0x/+?,+
* Created on 2007年1月1日, 下午4:57 @ 2_&ti
* w[&BY
* To change this template, choose Tools | Options and locate the template under -=w.tJD
* the Source Creation and Management node. Right-click the template and choose x&d<IU)5
* Open. You can then make changes to the template in the Source Editor. iDsjIW\j
*/ 9^tyjX2
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package com.tot.count; \!3='~2:=o
import tot.db.DBUtils; j3><J
import java.sql.*; LmE-&
/** A5b}G
* 8TZe=sD~cr
* @author g d -fJ._1
*/ mN`a]L'
public class CountControl{ MgekLP)&
private static long lastExecuteTime=0;//上次更新时间 T$e_ao|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 I
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/** Creates a new instance of CountThread */ uu>g(q?4II
public CountControl() {} a4yU[KK
public synchronized void executeUpdate(){ NO1PGen
Connection conn=null; s5HbuyR^
PreparedStatement ps=null; T"jl;,gr]J
try{ LFC k6 R
conn = DBUtils.getConnection(); >+r2I%
conn.setAutoCommit(false); vhC"f*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?m6E@.{
for(int i=0;i<CountCache.list.size();i++){ ]2jnY&a5
CountBean cb=(CountBean)CountCache.list.getFirst(); G r)+O
CountCache.list.removeFirst(); ]rS+v^@QH
ps.setInt(1, cb.getCountId()); C1J'. !
ps.executeUpdate();⑴ -_3.]o/J
//ps.addBatch();⑵ b%BwGS(z
} :vj buqN]
//int [] counts = ps.executeBatch();⑶ {~SR>I3sv
conn.commit(); y[cAU:P?
}catch(Exception e){ >7|37a
e.printStackTrace(); *K;~V
} finally{ 2+.m44>Ti
try{ z!%}0
if(ps!=null) { e#wn;wo?
ps.clearParameters(); $f+9svq
ps.close(); bpzA '
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ps=null; gS%J`X$
} Z&%61jGK
}catch(SQLException e){} wa C%o%fD
DBUtils.closeConnection(conn); VYBl0!t
} cmTZ))m
} epnDvz\
public long getLast(){ O
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return lastExecuteTime; ]q j%6tz
} L2$%h1
public void run(){ E=y#~W
long now = System.currentTimeMillis(); M@8(h=
if ((now - lastExecuteTime) > executeSep) { }Y[.h=X
//System.out.print("lastExecuteTime:"+lastExecuteTime); 6=
//System.out.print(" now:"+now+"\n"); Q|>y2g!
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); D"MNlm
lastExecuteTime=now; VioVtP0
executeUpdate(); KH;e)91
} eR/7*G5
else{ a4wh-35/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (n<xoV[e
} 46vz=# ,6L
} 0ode&dB
} C8?/$1|RL
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 +#W5Qb}VR
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类写好了,下面是在JSP中如下调用。 ,MLPVDN*D
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<% loZfzN&6A
CountBean cb=new CountBean(); Na=q(OKN
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ukw'$Yt2
CountCache.add(cb); dL"v*3Fy
out.print(CountCache.list.size()+"<br>"); ()7=(<x{
CountControl c=new CountControl(); NM4 n
c.run(); lBCM;#P
out.print(CountCache.list.size()+"<br>"); &(K*TB|Om
%>