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: -**fT?n
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CountBean.java !W=2ZlzS
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/* A{')
* CountData.java I+Fr#1
* \}Pr!tk!
* Created on 2007年1月1日, 下午4:44 i'#%t/ u
* 8mX:*$qm:
* To change this template, choose Tools | Options and locate the template under Io_7
* the Source Creation and Management node. Right-click the template and choose +.hJ[|F1&
* Open. You can then make changes to the template in the Source Editor. (Pt*|@i2c
*/ _&xkj8O
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package com.tot.count; ACgWT
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/** _'s5FlZq
* \z2d=E
* @author u)ZZ/|
*/ ['0^gN$:e
public class CountBean { IRI<no
private String countType; c;R.rV<
int countId; uYc&Q$U
/** Creates a new instance of CountData */ Zo,]Dx
public CountBean() {} a+\s 0Qo<
public void setCountType(String countTypes){ l02aXxT)]
this.countType=countTypes; P$G|o|h
} Mz6|#P}.s
public void setCountId(int countIds){ Z?w=-
this.countId=countIds; +T7FG_
} 89A04HX
public String getCountType(){ Szlww
return countType; ] m^ECA$
} .MRLAG
public int getCountId(){ sF#t{x/sW
return countId; It^_?oiK
} /3~}= b
} sZU
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CountCache.java ]}AyDy6C
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/* %M05& <
* CountCache.java {|@N~c+
* >[g'i+{
* Created on 2007年1月1日, 下午5:01 7jF2m'(
* 2?owXcbx
* To change this template, choose Tools | Options and locate the template under &44?k:
* the Source Creation and Management node. Right-click the template and choose ]^l-k@
* Open. You can then make changes to the template in the Source Editor. Xc]Q_70O
*/ \Ng[lN
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package com.tot.count; O,KlZf_B
import java.util.*; dtq]_HvTJ
/** yAVt[+0
* vy F(k3W
* @author k+cHx799
*/ cGjkx3l*
public class CountCache { eD 7Rv<
public static LinkedList list=new LinkedList(); W-ECmw(
/** Creates a new instance of CountCache */ rYr.mX
public CountCache() {} cNqw(\rr
public static void add(CountBean cb){ {eo?vA8SE
if(cb!=null){ /?QBMI
list.add(cb); p&;,$KDA
} :~9F/Jx
} w9a6F
} cV)~%e/
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CountControl.java <3Hu(Jx<O
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/* ::kpAE]
* CountThread.java JTB5#S4W
* }L*cP;m#
* Created on 2007年1月1日, 下午4:57 KHXnB
* pG:)u
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* To change this template, choose Tools | Options and locate the template under u@zBE?
g
* the Source Creation and Management node. Right-click the template and choose -^7n+
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* Open. You can then make changes to the template in the Source Editor. uc;QSVWGy8
*/ 9Uh nr]J.
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package com.tot.count; _26F[R1><~
import tot.db.DBUtils; x;*KRO
import java.sql.*; bwh.ekf8
/** qT L@N9
* !b+Kasss9
* @author D<cHa |
*/ V]9?9-r
public class CountControl{ b}r3x&)
private static long lastExecuteTime=0;//上次更新时间 OC[(Eq
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 v4Q8RE?
/** Creates a new instance of CountThread */ {z}OZHJN
public CountControl() {} >j$CM:w
public synchronized void executeUpdate(){ =
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Connection conn=null; bx<7@
PreparedStatement ps=null; D}Lx9cL
try{ ,!4(B1@
conn = DBUtils.getConnection(); /fc@=CO
conn.setAutoCommit(false); ,Z I"+v
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "GofQ5,|
for(int i=0;i<CountCache.list.size();i++){ -gV'z5
CountBean cb=(CountBean)CountCache.list.getFirst(); w~g)Dz2G
CountCache.list.removeFirst(); `4 A%BKYB
ps.setInt(1, cb.getCountId()); 6y9#am?
ps.executeUpdate();⑴ F
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//ps.addBatch();⑵ @YTZnGG*
} bXiT}5mJU
//int [] counts = ps.executeBatch();⑶ u|D_"q~+6
conn.commit(); A3N<;OOk
}catch(Exception e){ !(Y23w*
e.printStackTrace(); f"5vpU^5*
} finally{ [nlW}1)46
try{ Tce2]"^;
if(ps!=null) { VscEdtkd
ps.clearParameters(); uIvE~<
ps.close(); f z8eL:i:
ps=null; cf0Dq~G
} o3l_&?^
}catch(SQLException e){} Xu:Sh<:R
DBUtils.closeConnection(conn); 'DQKpk'
} (v8jVbg
} ]f q.r
public long getLast(){ x*[\$E`v
return lastExecuteTime; /wL}+
} Y m|zM1qc
public void run(){ {e?D6`#x
long now = System.currentTimeMillis(); mPxph>o
if ((now - lastExecuteTime) > executeSep) { ~8Z0{^
//System.out.print("lastExecuteTime:"+lastExecuteTime); :_Y@,CpIEg
//System.out.print(" now:"+now+"\n"); GV([gs
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); igsJa1F
lastExecuteTime=now; rr#&0`]
executeUpdate(); ;p#)z/zZ
} MI@id
else{ DEL#MD!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); n-{G19?
} p/xxoU
} snV,rZ
} t3b%f`D
//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 N$H0o+9-Y
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类写好了,下面是在JSP中如下调用。 ?y7x#_Exc
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<% y!Q&;xO+!
CountBean cb=new CountBean(); ]-&
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .3&zP
CountCache.add(cb); (yCFpb
out.print(CountCache.list.size()+"<br>"); 8|w_PP1oE
CountControl c=new CountControl(); iP;X8'< BC
c.run(); nJ4i[j8
out.print(CountCache.list.size()+"<br>"); Qsc%qt-l
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