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: FO2e7p^Q
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CountBean.java WUYI1Ij;
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/* 5W Ql?yMP
* CountData.java kTvM,<
* D4=*yP
* Created on 2007年1月1日, 下午4:44 79h~w{IT@
* fW-C`x
* To change this template, choose Tools | Options and locate the template under ShB]U5b:k
* the Source Creation and Management node. Right-click the template and choose .;?!I_`
* Open. You can then make changes to the template in the Source Editor. !
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*/ UD.bb
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package com.tot.count; 75^6?#GS
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/** x}] 56f
* LIZB!S@V \
* @author 3 t,_{9
*/ ix3LB!k<
public class CountBean { Zl9@E;|=
private String countType; )%7P?^>
int countId; /'/I^ab
/** Creates a new instance of CountData */
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public CountBean() {} isZ5s\
public void setCountType(String countTypes){ "D(Lp*3hj&
this.countType=countTypes; }|P3(*S
} .hl_zc#
public void setCountId(int countIds){ Z3`EXs
this.countId=countIds; Ww7Ya]b.k
} _wq?Pa<)e
public String getCountType(){ &R94xh%@(
return countType; &|hK79D
} :?t~|7O:
public int getCountId(){ 2c9?,Le/;
return countId; Gt`7i(
} P$)g=/td1
} }s}g}t8v-
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CountCache.java /at7H!
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/* P49\A^5S!
* CountCache.java @+u>rS|IB
* *DL7p8
* Created on 2007年1月1日, 下午5:01 ScPVjqG2{
* v,KKn\X
* To change this template, choose Tools | Options and locate the template under 4-(kk0]`z
* the Source Creation and Management node. Right-click the template and choose ~6 6xO9s
* Open. You can then make changes to the template in the Source Editor. m#7(<#
*/ >Fel) a
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package com.tot.count; $]v}X},,
import java.util.*; ,erw(7}'.
/** ;5[KZ8j6Y
* 1vj/6L
* @author F!omkN
*/ `9~
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public class CountCache { "/W[gP[y%
public static LinkedList list=new LinkedList(); 3N7H7(IR
/** Creates a new instance of CountCache */ uDF;_bli)H
public CountCache() {} Fhoyji4
public static void add(CountBean cb){ OZ[ YB
if(cb!=null){ fr@F7s5}
list.add(cb); 9njwAKF?
} =CX1jrLZ
} ^kez]>
} K@D\5s|1|
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CountControl.java V>Wk\'h
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/* r* *zjv>
* CountThread.java M^FY6TT4O
* o96C^y{~S
* Created on 2007年1月1日, 下午4:57 "W|A^@r}
* n<I{x^!
* To change this template, choose Tools | Options and locate the template under rwm^{Qa
* the Source Creation and Management node. Right-click the template and choose IPiV_c-l
* Open. You can then make changes to the template in the Source Editor. sibYJK Oy
*/ ZO0 Ee1/
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package com.tot.count; \o9 \ikR
import tot.db.DBUtils; )9QtnM
import java.sql.*; \;LDE`Q_x
/** 7>vm?a^D2&
*
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* @author r"h;JC/&<T
*/ {$*N1$(%
public class CountControl{ |c_qq Bd
private static long lastExecuteTime=0;//上次更新时间 jc}G+|`
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 TJ|Jv8j<s
/** Creates a new instance of CountThread */ I2cz:U7
public CountControl() {} }f}. >B0#
public synchronized void executeUpdate(){ ' W/M>!X
Connection conn=null; ?6#won
PreparedStatement ps=null; c0!.ei
try{ .L'w/"O
conn = DBUtils.getConnection(); [6/QUD8
conn.setAutoCommit(false); \mqx '
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); c8RJOc4X
for(int i=0;i<CountCache.list.size();i++){ }aCa2%
CountBean cb=(CountBean)CountCache.list.getFirst(); XYE|=Tr]
CountCache.list.removeFirst(); x0*{oP
ps.setInt(1, cb.getCountId()); M `xiC
ps.executeUpdate();⑴ q'2vE;z Kb
//ps.addBatch();⑵ EE/mxN(<
} 3a/n/_D
//int [] counts = ps.executeBatch();⑶ ~E<2gMKjO
conn.commit(); d:H'[l.F%
}catch(Exception e){ l'@-?p(Vuw
e.printStackTrace(); 2G8pDvBr
} finally{ >@ t
try{ 9>""xt
if(ps!=null) { 6_LeP9s )
ps.clearParameters(); 2Xb,
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ps.close(); 6%D9;-N)
ps=null; )G? qX.D
} p{FI_6db
}catch(SQLException e){} Bf_$BCyGW
DBUtils.closeConnection(conn); '`];=QY9pg
} H=r-f@EOrI
} t>"%exdoZ
public long getLast(){ d|`Ll
return lastExecuteTime; v*;d
} lWbu`y
public void run(){ xNP_>Qa~
long now = System.currentTimeMillis(); 7ubz7*
if ((now - lastExecuteTime) > executeSep) { p 7?
//System.out.print("lastExecuteTime:"+lastExecuteTime); vDy&sgS$<
//System.out.print(" now:"+now+"\n"); p7h#.m~Qu
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +Y\:Q<eMFg
lastExecuteTime=now; }\pI`;*O|
executeUpdate(); P T"}2sR)
} J
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else{ H'+7z-%G
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {4"V)9o-1>
} 9g9 2eKS
} S{YzHK
} u8e_Lqx?
//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 jm_-f
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类写好了,下面是在JSP中如下调用。 *bkb-nKw
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<% {Gxe%gu6K
CountBean cb=new CountBean(); 7
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :Pud%}'
CountCache.add(cb); )?n'ZhsX
out.print(CountCache.list.size()+"<br>"); "Fz.#U
CountControl c=new CountControl(); "gM^o
c.run(); >rnVTK
out.print(CountCache.list.size()+"<br>"); U"oNJ8&%|
%>