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: U-lN-/=l6
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CountBean.java uDsof?z
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/* d(;Qe}ok>
* CountData.java p^9u8T4l1
* t^(wbC
* Created on 2007年1月1日, 下午4:44 cA25FD
* (xlAS
* To change this template, choose Tools | Options and locate the template under VVm8bl.q
* the Source Creation and Management node. Right-click the template and choose OjBg$f~0F
* Open. You can then make changes to the template in the Source Editor. ^HI}bS1+|
*/ `T~~yM)q
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package com.tot.count; t.= 1<Ed
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/** fv?vfI+m
* GHR,KB7 xM
* @author K*fh`Kz
*/ /GMT
public class CountBean { %Astfn(U{4
private String countType; 6xAR:
int countId; 2]/[
/** Creates a new instance of CountData */ 4/ M~#
public CountBean() {} }='1<~0
public void setCountType(String countTypes){ ?(P3ZTk?.
this.countType=countTypes; 6A*k
} D}6~2j
public void setCountId(int countIds){ c(G;O)ikS
this.countId=countIds; Q
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} |XoW
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public String getCountType(){ ELqpIXq#
return countType; Y76U htYH
} F)^:WWVc#
public int getCountId(){ Kitx%P`i
return countId; ?^z.WQ|f@
} l~i&r?,]^
} pv9Z-WCix$
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CountCache.java qZ|>{^a*
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/* f=/IwMpn
* CountCache.java n#lZRwhq
* o9#8q_D9
* Created on 2007年1月1日, 下午5:01 u?+i5=N9{
* v"N%w1`.e
* To change this template, choose Tools | Options and locate the template under +ZK12D}
* the Source Creation and Management node. Right-click the template and choose 7lYiu fg
* Open. You can then make changes to the template in the Source Editor. C!Oz'~l
*/ haW*W=kv)
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package com.tot.count; V'jvI
import java.util.*; smTPca)7s
/**
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* m0zbG1OE
* @author Bp>Z?"hTe
*/ Iurb?
public class CountCache { 6o4Bf| E]
public static LinkedList list=new LinkedList(); (h3f$
/** Creates a new instance of CountCache */ >^5UXQr
public CountCache() {} DcL;7 IT
public static void add(CountBean cb){ vv%
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if(cb!=null){ z1R_a=7
list.add(cb); _cw~N
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} s}5,<|DL
} 1o*eu&@
} (_aM26s
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CountControl.java ?f\ ~:Gm/
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/* N& 683z
* CountThread.java Ns}BE H
* f;7I{Z\<
* Created on 2007年1月1日, 下午4:57 7)U08"
* d=v{3*a_4,
* To change this template, choose Tools | Options and locate the template under :,'yHVG\
* the Source Creation and Management node. Right-click the template and choose 0
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* Open. You can then make changes to the template in the Source Editor. R@[gkj
*/ n#Y=y#
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package com.tot.count; )=]u]7p}
import tot.db.DBUtils; }Jr!aM'
import java.sql.*; 7)Y0D@wg
/** xP61^*-2
*
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* @author _a`J>~$
*/ A<$w
}Fy;
public class CountControl{ ~p* \|YC
private static long lastExecuteTime=0;//上次更新时间 Q`{2yU:r
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6PyODW;R/5
/** Creates a new instance of CountThread */ [d^ [Y:I'\
public CountControl() {} )' 3V4Z&
public synchronized void executeUpdate(){ ]aN]H a
Connection conn=null; XQhbH^
PreparedStatement ps=null; d09qZj>
try{ ' ] $mt
conn = DBUtils.getConnection(); I #8TY/XP
conn.setAutoCommit(false); 6Ex16
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); #P)(/>nF
for(int i=0;i<CountCache.list.size();i++){ j+6`nN7L
CountBean cb=(CountBean)CountCache.list.getFirst(); ucwUeRw,
CountCache.list.removeFirst(); VTIRkC
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ps.setInt(1, cb.getCountId()); !bGMVw6_
ps.executeUpdate();⑴ qvN`46c
//ps.addBatch();⑵ W#sCvI@
} > %B7/l$
//int [] counts = ps.executeBatch();⑶ nSR<( -j!
conn.commit(); cI/Puh^3
}catch(Exception e){ L2}p<?f
e.printStackTrace(); tB/'3#o
} finally{ e]k\dj;,^%
try{ 3@8Zy:[8<
if(ps!=null) { U3OXO1
ps.clearParameters(); <Dq7^,}#
ps.close(); 1}XESAX;0
ps=null; 9JBVG~m+
} 8d|#W
}catch(SQLException e){} Cak-J~=
DBUtils.closeConnection(conn); 2}xvM"k=k
} $dkkgsw7
} t=BXuFiu
public long getLast(){ j3&tXZ;F
return lastExecuteTime; %XiF7<A&
} \_|g}&}6Y
public void run(){ sHn-#SGm
long now = System.currentTimeMillis(); <
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if ((now - lastExecuteTime) > executeSep) { _<m yM2z
//System.out.print("lastExecuteTime:"+lastExecuteTime); B82SAV/O
//System.out.print(" now:"+now+"\n"); Lxqv
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); qfS
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lastExecuteTime=now; K!jMW
executeUpdate(); I6lWB(H!u
} 4KnrQ-D
else{ -]!zj#&
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Ro:)N:C
} V PaW-o
} JGG (mrvR
} rGUu K0L&
//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 Gm.2!F=R4A
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类写好了,下面是在JSP中如下调用。 ~Sc{\ZJl
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<% v)s;
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CountBean cb=new CountBean(); >}) W5Y+
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); i&Xjbcbp
CountCache.add(cb); V8-*dE
out.print(CountCache.list.size()+"<br>"); 7 DW_G
CountControl c=new CountControl(); +Vw]DLWR
c.run(); bD4aSubN
out.print(CountCache.list.size()+"<br>"); Pt\GVWi_t
%>