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: S% JNxT7'
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CountBean.java z5x,fQw6O
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/* qR [}EX&3
* CountData.java q`/amI0
* vDu0
* Created on 2007年1月1日, 下午4:44 ^/`#9]<%
* LP5eFl`|T
* To change this template, choose Tools | Options and locate the template under zznPD%#Sc
* the Source Creation and Management node. Right-click the template and choose J{nyo1A
* Open. You can then make changes to the template in the Source Editor. jw:4fb
*/ N&0uXrw
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package com.tot.count; 8\qCj.>S
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/** xm%[}Dt]
* l|@/?GaH
* @author GW>7R6i
*/ H j5WJ{p.
public class CountBean { 6e$sA (a=i
private String countType; &%f ]-=~
int countId; aBqe+FXp4
/** Creates a new instance of CountData */ {V]Qwz)1
public CountBean() {} mV:RmA
public void setCountType(String countTypes){ A@@)lD.
this.countType=countTypes; &xGfkCP.]
} Uy$U8b-ov
public void setCountId(int countIds){ $nGbT4sc
this.countId=countIds; rZ8Y=) e
} Q.pEUDq/
public String getCountType(){ H y.3ccZ0
return countType; t6<sNzF&
} fG8}= xH_&
public int getCountId(){ %#Wg^l
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return countId; Vq .!(x
} `5k6s,
} \J,- <wF
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CountCache.java dbMu6Bm\G
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/* O, ``\(P
* CountCache.java <\}Y@g8
* F653[[eQ
* Created on 2007年1月1日, 下午5:01 lry&)G=5
* #czyr@
* To change this template, choose Tools | Options and locate the template under TzevC$m;z
* the Source Creation and Management node. Right-click the template and choose A1k&`
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* Open. You can then make changes to the template in the Source Editor. ~q8V<@?
*/ r3c\;Ra7
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package com.tot.count; l$p_])x
import java.util.*; Cdt,//xrz
/** 48~m=mI
* YL9t3]
* @author s!j(nUd/
*/ RXx?/\~yd;
public class CountCache { r.a9W?(E
public static LinkedList list=new LinkedList(); .kB3jfw0,
/** Creates a new instance of CountCache */ wCq)w=,
public CountCache() {} I(?|Ox9"?
public static void add(CountBean cb){ XD+cs.{5
if(cb!=null){ _V7^sk!
list.add(cb); XftJ= *
} @KW+?maW
} WfTdD.Xx
} ltr;pc*)
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CountControl.java j0pvLZjM
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/* OuBMVn
* CountThread.java %8}ksl07
* Xg!|F[i
* Created on 2007年1月1日, 下午4:57 #nc@!+
* jC/JiI
* To change this template, choose Tools | Options and locate the template under M;p q2$
* the Source Creation and Management node. Right-click the template and choose LHHDt<+B
* Open. You can then make changes to the template in the Source Editor. y9G 57D
*/ }%>$}4 ,
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package com.tot.count; |{/O)3
import tot.db.DBUtils; [^(R1K
import java.sql.*; 0ZID
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/** C(t6;&H
* { Sliy'
* @author m"|(w`n]E+
*/ 8F\Msx
public class CountControl{ Zs$RKJ7
private static long lastExecuteTime=0;//上次更新时间 xwH|ryfs,Z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <1g 1hqK3
/** Creates a new instance of CountThread */ #g`cih=QL
public CountControl() {} oIL+@}u7
public synchronized void executeUpdate(){ E=1/
Connection conn=null; L%s4snE
PreparedStatement ps=null; m/F(h-?
try{ xZ'`_x9l
conn = DBUtils.getConnection(); jVFRq T%
conn.setAutoCommit(false); Hj4w
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); w6In{uO-Z
for(int i=0;i<CountCache.list.size();i++){ mKFHT
CountBean cb=(CountBean)CountCache.list.getFirst(); zju,#%
CountCache.list.removeFirst(); W$MEbf%1
ps.setInt(1, cb.getCountId()); Z=t#*"J
ps.executeUpdate();⑴ FiU;>t<)
//ps.addBatch();⑵ :Ye#NPOI
} yE|}
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//int [] counts = ps.executeBatch();⑶ gl7vM
conn.commit(); >
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}catch(Exception e){ v^18o$=K",
e.printStackTrace(); DdS3<3]A
} finally{ y:[VRLo
try{ }`/n2
if(ps!=null) { KjfKo;T
ps.clearParameters(); M>H^<N}'A
ps.close(); NF)\">Ye
ps=null; ^xNe Eb
} -MW(={#
}catch(SQLException e){} |9"^s x
DBUtils.closeConnection(conn); dj&m
} "O1*uwm
} H[!Q
public long getLast(){ b=
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return lastExecuteTime; "`gZy)E
} f`]E]5?
public void run(){ E?h2e~ ,]
long now = System.currentTimeMillis(); % m5 ^p
if ((now - lastExecuteTime) > executeSep) { {ugKv?e;
//System.out.print("lastExecuteTime:"+lastExecuteTime); sS2E8Z2
//System.out.print(" now:"+now+"\n"); 2gR_1*|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); I
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lastExecuteTime=now; Sq8Q*
executeUpdate(); I)%jPH:ua
} -L50kk>h
else{ /?-p^6U
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); `1}?{ud
} _3G)S+7#
} [W;dguh
} BRzWZq%r3
//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 {s'_zSz
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类写好了,下面是在JSP中如下调用。 !E#.WX
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<% _@;3$eB
CountBean cb=new CountBean(); z2q5f:d8
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^PR,TR.
CountCache.add(cb); 2bxMIr
out.print(CountCache.list.size()+"<br>"); 2m_M9e\
CountControl c=new CountControl(); Q|z06_3i
c.run(); o9d$
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out.print(CountCache.list.size()+"<br>"); u#,'ys
%>