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: <{P`A%g@
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CountBean.java |5TzRz
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/* [JVEKc ym
* CountData.java w&[&ZDsK
* ISHzlEY
* Created on 2007年1月1日, 下午4:44 fW=vN0Z
* cw3j&k
* To change this template, choose Tools | Options and locate the template under ko{7^]gR
* the Source Creation and Management node. Right-click the template and choose =n<Lbl(7
* Open. You can then make changes to the template in the Source Editor. Bw/8-:eb
*/ Rn$[P.||
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package com.tot.count; of=N+
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/** JnIE6@g<y
* G
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* @author hN^,'O
*/ IqAML|C
public class CountBean { [9^lAhX
private String countType; =1Hn<Xay0
int countId; dym K @
/** Creates a new instance of CountData */ }0V aZ<j
public CountBean() {} 4w5);x.
public void setCountType(String countTypes){ #w@V!o
this.countType=countTypes; bRD-[)
} +L|x^B3
public void setCountId(int countIds){ E?-
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this.countId=countIds; 0[]) wl
} N 9W,p2
public String getCountType(){ i__f%j`!W
return countType; ,@kLH"a0
} > JC"YB
public int getCountId(){ l;d4Le
return countId; C#LTF-$])
} />n!2'!
} `a `>Mtl
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CountCache.java JNv@MJb}
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/* -}u1ZEND
* CountCache.java " GY3sam
* !bs5w_@
* Created on 2007年1月1日, 下午5:01 X-*LA*xbN
* :nOI|\rC
* To change this template, choose Tools | Options and locate the template under N[A9J7}_R
* the Source Creation and Management node. Right-click the template and choose ,bzC|AK
* Open. You can then make changes to the template in the Source Editor. IIN,Da;hD
*/ ,T*\9'Q
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package com.tot.count; Gz52^O:
import java.util.*; U+R9bn
/** U(gYx@
* (mplo|>
* @author ~O~iP8T
*/ EW`3$J;
public class CountCache { }
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public static LinkedList list=new LinkedList(); .k$Yleg
/** Creates a new instance of CountCache */ xR8y"CpE
public CountCache() {} ~ mz X1[
public static void add(CountBean cb){ h=Q2
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if(cb!=null){ VTU(C&"S
list.add(cb); eA*We
} fA"c9(>m%]
} Q zg?#|
} pk`5RDBu
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CountControl.java Zv2]X-
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/* 8"TlWHF`
* CountThread.java &@FufpPw/
* 4
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* Created on 2007年1月1日, 下午4:57 Jd~M q9(
* jGoQXiX
* To change this template, choose Tools | Options and locate the template under \x:} |
* the Source Creation and Management node. Right-click the template and choose H_,4N_hL
* Open. You can then make changes to the template in the Source Editor. B2Rpd &[
*/ fw
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package com.tot.count; R;pIi/yDRe
import tot.db.DBUtils; BNe>Lk o
import java.sql.*; ~^'WHuzPy
/** ?gBFfi
* ~k%XW$cV
* @author ayh235>a(
*/ -BSO$'{7
public class CountControl{ b6xz\zCL
private static long lastExecuteTime=0;//上次更新时间 K:A:3~I!NW
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 9kwiG7V1
/** Creates a new instance of CountThread */ Nv|0Z'M
public CountControl() {} (>,b5g
public synchronized void executeUpdate(){ >6Jz=N,
Connection conn=null; XD"
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PreparedStatement ps=null; q6b&b^r+H
try{ T9'HQu
conn = DBUtils.getConnection(); #3tC"2MZ
conn.setAutoCommit(false); byTHSRt
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P,b&F
for(int i=0;i<CountCache.list.size();i++){ .4l
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CountBean cb=(CountBean)CountCache.list.getFirst(); ;VE KrVD
CountCache.list.removeFirst(); <2fy(9y
ps.setInt(1, cb.getCountId()); =**Q\Sl
ps.executeUpdate();⑴ %%#bTyF
//ps.addBatch();⑵ <Ql2+ev6
} 24
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//int [] counts = ps.executeBatch();⑶ GvvKM=1
conn.commit(); 0|i|z!N>
}catch(Exception e){ _T7XCXEk
e.printStackTrace(); }346uF7C
} finally{ Bz|/TV?X(
try{
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if(ps!=null) { I-=Ieq"R9
ps.clearParameters(); *yY\d.6(
ps.close(); 17`-eDd
ps=null; tv Zq):c
} m=Gb<)Y
}catch(SQLException e){} ;Wa&Dg/5`
DBUtils.closeConnection(conn); Jl6lZd(Np
} dt>9mF q
}
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public long getLast(){ X 4!Jj*
return lastExecuteTime; `
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} :6Tv4ZUvcG
public void run(){ &;`E3$>
long now = System.currentTimeMillis(); u.*}'C>^^v
if ((now - lastExecuteTime) > executeSep) { ZD7qw*3+
//System.out.print("lastExecuteTime:"+lastExecuteTime); ~3&hvm[IQ
//System.out.print(" now:"+now+"\n"); JStEOQF4
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^.
lastExecuteTime=now; B#}EYY
executeUpdate(); sl(go^
} yhI;FNSf
else{ ]rNxvFN*j
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); lgD%
}
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} :t;i2Ck
} -3y
//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 V#+F*w?&D
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类写好了,下面是在JSP中如下调用。 "!fwIEG
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<% Crl:v8
CountBean cb=new CountBean(); `Q/\w1-Q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 7Ka4?@bQ
CountCache.add(cb); 6#.9T;&
out.print(CountCache.list.size()+"<br>"); H<;~u:;8Q
CountControl c=new CountControl(); ]m7x&N2
c.run(); [wnaF|h
out.print(CountCache.list.size()+"<br>"); ]=]MJ3_7
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