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: /'l{E
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CountBean.java irFMmI b
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/* S >X:ZYYC
* CountData.java =S+wCN
* ;o2$
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* Created on 2007年1月1日, 下午4:44 m.#
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* bYpntV
* To change this template, choose Tools | Options and locate the template under t^R][Ay&
* the Source Creation and Management node. Right-click the template and choose bnq;)>&
* Open. You can then make changes to the template in the Source Editor. ' g=
*/ cdl&9-}
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package com.tot.count; bpJ(XN}E
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/**
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* 0WZ_7C?
* @author -Ta9 pxZk
*/ 8dZSi
public class CountBean { LsqA**=
private String countType; iNtaDX|%/
int countId; JQ8fdP A
/** Creates a new instance of CountData */ r@h5w_9
public CountBean() {} q<[P6}.
public void setCountType(String countTypes){ zZPuha8
this.countType=countTypes; e6R}0w~G
} _~IR6dKE
public void setCountId(int countIds){ B(LWdap~
this.countId=countIds; S;3R S;
} %GjM(;Tk
public String getCountType(){ );
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return countType; 0%&1\rm+j
} ;f0I
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public int getCountId(){ "pi=$/RD9
return countId; ]HKQDc'
} c}Ft^Il
} OE_XCZ!5P
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CountCache.java /32Fy`KV
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/* n7B7 m,@1
* CountCache.java $2oTkOA
* bhTb[r
* Created on 2007年1月1日, 下午5:01 &gVN&
* BZ94NOOdw
* To change this template, choose Tools | Options and locate the template under Su
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* the Source Creation and Management node. Right-click the template and choose p `8s
* Open. You can then make changes to the template in the Source Editor. 0bceI
*/ .0S~872
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package com.tot.count; 1n >X[!
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import java.util.*; ~P*6ozSYpY
/** <r.)hT"0
* bR*-Ht+wd
* @author KyVQh8
*/ Y}t \4 di
public class CountCache { 1tEgl\u\
public static LinkedList list=new LinkedList(); wKtl+}}
/** Creates a new instance of CountCache */ kw>v:F<M
public CountCache() {} /[a~3^Gs^
public static void add(CountBean cb){ q.KG^=10
if(cb!=null){ 6Z>FTz_
list.add(cb); A>vBQN
} UldXYtGe
} ''q@>
} O,+1<.;+
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CountControl.java MW! srTQ_
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/* y?[ v=j*U
* CountThread.java ciFmaM.
* V/%>4GYnC
* Created on 2007年1月1日, 下午4:57 oibsh(J3
* oI0M%/aM
* To change this template, choose Tools | Options and locate the template under [>+4^&
* the Source Creation and Management node. Right-click the template and choose s`M9
* Open. You can then make changes to the template in the Source Editor. aXQnZ+2e^R
*/ d?s<2RkPT
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package com.tot.count; oz,np@f)J
import tot.db.DBUtils; Jv>gwV{
import java.sql.*; j#X.KM
/** gFeO}otm
* kW2sY^Rg
* @author N+m)/x
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*/ nGpXI\K
public class CountControl{ T}Km?d
private static long lastExecuteTime=0;//上次更新时间 X\]L=>]C
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 l Q'I
/** Creates a new instance of CountThread */ Nh8Q b/::
public CountControl() {} NTdixfR
public synchronized void executeUpdate(){ (_niMQtF}
Connection conn=null; \a 5U8shc
PreparedStatement ps=null; ]9YJ,d@J
try{ $yn];0$J
conn = DBUtils.getConnection(); )<oJnxe]
conn.setAutoCommit(false); 3)F|*F3R
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =!kk|_0%E
for(int i=0;i<CountCache.list.size();i++){ M`. tf_x
CountBean cb=(CountBean)CountCache.list.getFirst(); !S^AgZ~
CountCache.list.removeFirst(); T m_bz&Q
ps.setInt(1, cb.getCountId()); yWg@v+
ps.executeUpdate();⑴ T_s_p
//ps.addBatch();⑵ Y#!UPhg<
} 4E;VM{
//int [] counts = ps.executeBatch();⑶ I!^;8Pg
conn.commit(); !9u|fnC9
}catch(Exception e){ zO~8?jDN4|
e.printStackTrace(); ]p _L)
} finally{
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try{ `Bo*{}E
if(ps!=null) { 33o9Yg|J~
ps.clearParameters(); V^7V[(~`
ps.close(); X>d"]GD
ps=null; Q;[,Q~c[u
} Z,RzN5eN
}catch(SQLException e){} O,J>/
DBUtils.closeConnection(conn); VeGL)
} aDq5C-MzG
} y[`l3;u:'
public long getLast(){ _a5d?Q9Z
return lastExecuteTime; pf%=h
|
} !g?|9
public void run(){ *?Lv3}E
long now = System.currentTimeMillis(); (*Z)(O*z
if ((now - lastExecuteTime) > executeSep) { hLI`If/+K
//System.out.print("lastExecuteTime:"+lastExecuteTime); W}--p fG
//System.out.print(" now:"+now+"\n"); qmnZAk
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !2 LCLN\
lastExecuteTime=now; NMW#AZVd
executeUpdate(); kjW+QT?T&
} ZO!I.
else{ Qt iDTr
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <A[E:*`*
} ~"!]
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} AuUde$l_
} Y,GU%[+
//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 _p#CwExuy
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类写好了,下面是在JSP中如下调用。 &+a9+y
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<% us;YV<)d
CountBean cb=new CountBean(); g'pK
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +1Vjw'P
CountCache.add(cb); CAWA3fcQp
out.print(CountCache.list.size()+"<br>"); iocI:b<
CountControl c=new CountControl(); 03xa'Of>
c.run(); O?NeSx1
out.print(CountCache.list.size()+"<br>"); S\''e`Eb"5
%>