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: .E?bH V
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CountBean.java .(TQ5/
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/* GoGohsj
* CountData.java f}Ne8]U/Hc
* s9ju/+fv
* Created on 2007年1月1日, 下午4:44 f.U0E6-(3N
* z'vdC
* To change this template, choose Tools | Options and locate the template under Tx|SAa=V
* the Source Creation and Management node. Right-click the template and choose v^y}lT
* Open. You can then make changes to the template in the Source Editor. ,(;p(#F>
*/ +cV5h
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package com.tot.count; j]@x Q,y
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/** SdjUhR+o
* Z`SWZ<
* @author
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*/ !q7;{/QM6
public class CountBean { w~cq%%
private String countType; w /Bn2bD
int countId; P%<aGb4
/** Creates a new instance of CountData */ *_2O*{V
public CountBean() {} -Fp!w "=T
public void setCountType(String countTypes){ }5TfQV6
this.countType=countTypes; :Ul'(@
} I>YtWY|ed
public void setCountId(int countIds){ t5X G^3X@
this.countId=countIds; $ g1wK}B3
} s/W!6JX4
public String getCountType(){ YYZs#_
return countType; !_^{udB}
} rA1zyZlz
public int getCountId(){ ^5FJ}MMJf
return countId; ,Do$`yO+
} 2m)kyQ
} Y1yvI
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CountCache.java 34+)-\ xt:
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/* )$9C` d[
* CountCache.java s&_IWala
* +[ZMrTW!0C
* Created on 2007年1月1日, 下午5:01 d
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* k
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* To change this template, choose Tools | Options and locate the template under }e/[$!35
* the Source Creation and Management node. Right-click the template and choose vJ'yz#tl9
* Open. You can then make changes to the template in the Source Editor. 4cErk)F4
*/ Q)%8NVs
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package com.tot.count; %(dV|,|v
import java.util.*; n}ZBU5_
/** ;*j6d3E
* ^Q43)H0
* @author @]y{M;
*/ 8IT_mjj
public class CountCache { D
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public static LinkedList list=new LinkedList(); #Tg|aW$(*
/** Creates a new instance of CountCache */ V!kQuQJ>
public CountCache() {} x]%4M\T``
public static void add(CountBean cb){ Chb4VoE
if(cb!=null){ D@lAT#vA
list.add(cb); y ? {PoNI
} c^dl+-{Mc
} =A6u=
} '^.=gTk
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CountControl.java 0N3tsIm>
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/* XCqfAcNQ
* CountThread.java =xlYQ}-(a
* gR_b~^
* Created on 2007年1月1日, 下午4:57 {%+3D,$)
* 1Hk<_no5
* To change this template, choose Tools | Options and locate the template under "z(fBnv
* the Source Creation and Management node. Right-click the template and choose 4?*"7t3
* Open. You can then make changes to the template in the Source Editor. i}$N&
*/ S#0|#Z5qD
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package com.tot.count; $U"P+
import tot.db.DBUtils; 8G[Y9A(bmP
import java.sql.*; #LNB@E
/** L2/<+Zw
* <76=H]h~
* @author K9z_=c+
*/ r/s&ee
public class CountControl{ |V~(mS747:
private static long lastExecuteTime=0;//上次更新时间 7,&]1+n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .>gU
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/** Creates a new instance of CountThread */ hF=V
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public CountControl() {} qS/71Kv'
public synchronized void executeUpdate(){ I}g|n0o
Connection conn=null; 45O6TqepN
PreparedStatement ps=null; ^&G O4u
try{ x"C93ft[
conn = DBUtils.getConnection(); ]a%\Q2[c
conn.setAutoCommit(false); CDTk
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); zm)CfEF
8
for(int i=0;i<CountCache.list.size();i++){ ^) b7m
CountBean cb=(CountBean)CountCache.list.getFirst(); WE Svkm;
CountCache.list.removeFirst(); ]K0,nj*\c
ps.setInt(1, cb.getCountId()); -)->Jx:{
ps.executeUpdate();⑴ pS|JDMo
//ps.addBatch();⑵ m(7_ZiL=
} ~V$5 m j
//int [] counts = ps.executeBatch();⑶ H@&"M%
conn.commit(); >*Qk~kv<%
}catch(Exception e){ BS<>gA
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e.printStackTrace(); E<m"en&v
} finally{ Dk{nOvZu<
try{ "6Hjji@A
if(ps!=null) { Vo9)KxR
ps.clearParameters(); abk:_
ps.close(); [F>n!`8
ps=null; :+Je989\[C
} .D2ub/er
}catch(SQLException e){} Z5^,!6
DBUtils.closeConnection(conn); lj}1'K@M
} PRf\6
} A&_i]o
public long getLast(){ t;a}p_>
return lastExecuteTime; ?$8 ,j+&I
} =B{$U~}
public void run(){ DrCfC[A~]
long now = System.currentTimeMillis(); nrD=[kc!w
if ((now - lastExecuteTime) > executeSep) { jQwg)E+o;
//System.out.print("lastExecuteTime:"+lastExecuteTime); v'Py[[R
//System.out.print(" now:"+now+"\n"); ^MWW,`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &B5Rzz-'
lastExecuteTime=now; CYic_rF$
executeUpdate(); \?mU$,voI
} NN pa69U
else{ G?/8&%8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1.OXkgh
} Y<$"]@w
} W,oV$ s^
} :w`i
//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 kU9AfAe
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类写好了,下面是在JSP中如下调用。 ;7og
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<% 1nM?>j%k
CountBean cb=new CountBean(); j~j
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ne~#{q
CountCache.add(cb); GH)+yD[o
out.print(CountCache.list.size()+"<br>"); ~|d?o5W
CountControl c=new CountControl(); [`nyq )
c.run(); PT*@#:MA
out.print(CountCache.list.size()+"<br>"); +z/73s0~
%>