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: \}Wkj~IX
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CountBean.java &B2c]GoW
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/* =%u|8Ea*`
* CountData.java NY;UI(<]
* q7]WR(e
* Created on 2007年1月1日, 下午4:44 qB39\j
* LAKZAi%O0
* To change this template, choose Tools | Options and locate the template under ~ghz%${`
* the Source Creation and Management node. Right-click the template and choose ^VIUXa
* Open. You can then make changes to the template in the Source Editor. G9a%N
*/
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package com.tot.count; }F`Tp8/&j
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/** oto od
* "[?/I3{E
* @author ?xo,)``
*/ i]-gO
public class CountBean { _]S6>
private String countType; +{%4&T<nHw
int countId; 55cldo
/** Creates a new instance of CountData */ ]6;AK\9TM
public CountBean() {} 7, 13g)
public void setCountType(String countTypes){ /T(\}Z
this.countType=countTypes; g"&bX4uD)
} 4@V]zfu^Q
public void setCountId(int countIds){ 5p|@ )
this.countId=countIds; } >w
} (rG1_lUDu
public String getCountType(){ XH *tChf<
return countType; D+)=bPMe
} ._&lG3'
public int getCountId(){ N.G*ii\
return countId; _tReZ(Vw
} !TOi]`vqc
} pu:D/2R2;k
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CountCache.java 1a$V{Eag
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/* Crhi+D
* CountCache.java u,akEvH~a
* U&n>fXTHn
* Created on 2007年1月1日, 下午5:01 $048y
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* z^/ GTY
* To change this template, choose Tools | Options and locate the template under ]Z-oUO
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* the Source Creation and Management node. Right-click the template and choose 0GYEt
* Open. You can then make changes to the template in the Source Editor. 9f^PR|F
*/ 6}T%m?/ }
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package com.tot.count; euhZ4+
import java.util.*; cXY'>N
/** =[K)<5,@
* ?66(t
* @author E.`dk.
*/ {?mQqoZ?.
public class CountCache { !ix<|F5
public static LinkedList list=new LinkedList(); IOkC [([
/** Creates a new instance of CountCache */ w;EXjl;X O
public CountCache() {} GeaDaYh#T
public static void add(CountBean cb){ (<3lo
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if(cb!=null){ lZM3Q58?\
list.add(cb); dl6v
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} ^A[`NYK
} '98h<(@]
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CountControl.java gww^?j#
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/* =_=Z;#`cXk
* CountThread.java HQ3`:l
* @7s,|\
* Created on 2007年1月1日, 下午4:57 &U~r}=
* a9Fm Y`
* To change this template, choose Tools | Options and locate the template under iEviH>b5
* the Source Creation and Management node. Right-click the template and choose jN%p5nZ^EK
* Open. You can then make changes to the template in the Source Editor. vif8{S
*/ A<Z5
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package com.tot.count; ^dnz=FB
import tot.db.DBUtils; PGPbpl&\t
import java.sql.*; I26gGp
/** S[~O')
* cN WcNMm
* @author Px#QZZ
*/ [Hj'nA^
public class CountControl{ LBkc s4+
private static long lastExecuteTime=0;//上次更新时间 q Iy^N:C2'
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 WjrMd#^
/** Creates a new instance of CountThread */ %Lp7@
public CountControl() {} T]6c9_
public synchronized void executeUpdate(){ V<vPFxC
Connection conn=null; 2]} Uov
PreparedStatement ps=null; +&7Kk9^
try{ ,=Nw(GI
conn = DBUtils.getConnection(); `8(h,aj;
conn.setAutoCommit(false); o? i.v0@!K
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); k&A7alw
for(int i=0;i<CountCache.list.size();i++){ nF<y7XkO
CountBean cb=(CountBean)CountCache.list.getFirst(); lW$&fuDHF
CountCache.list.removeFirst(); Z|(c(H2
ps.setInt(1, cb.getCountId()); )J+{oB[>b
ps.executeUpdate();⑴ %A62xnX
//ps.addBatch();⑵ 5eOj,[?
} BY*2yp}7
//int [] counts = ps.executeBatch();⑶ tP`G]BCbt
conn.commit(); QM ZUt
}catch(Exception e){ '}Wu3X
e.printStackTrace(); +lW}ixt
} finally{ adI!W-/R:
try{ 8pPC 9ew\=
if(ps!=null) { ^.#X<8hr
ps.clearParameters();
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ps.close(); x_<bK$OU
ps=null; /S]:dDY9K
} [vWkAJ'K
}catch(SQLException e){} eOehgU5x
DBUtils.closeConnection(conn); )[^y
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} \-
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} "%E-X:Il#
public long getLast(){ y|6@-:B.
return lastExecuteTime; `~_H=l9{
} S,9NUt
public void run(){ E69:bQ94u
long now = System.currentTimeMillis(); PZuq'^p
if ((now - lastExecuteTime) > executeSep) { (/U)>%n
//System.out.print("lastExecuteTime:"+lastExecuteTime); Jq$_=X&
//System.out.print(" now:"+now+"\n"); 5fu+rU-#
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,\lYPx\P[
lastExecuteTime=now; %o@['9U[j
executeUpdate(); 2f19W#
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} (Pv`L
else{ xHJ8?bD p
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Q1`<fD
} f v E+.{
} rFmKmV
} /5Zp-Pq
//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 ]<kupaRQ
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类写好了,下面是在JSP中如下调用。 X,TTM,1w
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<% u C,"5C
CountBean cb=new CountBean(); a)!![X?\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9-
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CountCache.add(cb); mRhd/|g*
out.print(CountCache.list.size()+"<br>"); ><NI'q*cQ
CountControl c=new CountControl(); <0u\dU
c.run(); vi]r
out.print(CountCache.list.size()+"<br>"); &8<<!#ob
%>