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: sd9$4k"
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CountBean.java +^ a9i5
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/* HeABU(o4
* CountData.java M4
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* 5OeTOI()&5
* Created on 2007年1月1日, 下午4:44 bwo-9B
* Mx{VN
P
* To change this template, choose Tools | Options and locate the template under mAMi-9
* the Source Creation and Management node. Right-click the template and choose !+T\}1f7d
* Open. You can then make changes to the template in the Source Editor. jXA!9_L7
*/ Go~bQ2*'(/
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package com.tot.count; rE0?R(_
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/** z@;]Hy
* jy@vz,/:%5
* @author f0p+l-iEv
*/ QK _1!t3
public class CountBean { +v4P9V|s
private String countType; j1_ E^
int countId; PN9^ sLx=
/** Creates a new instance of CountData */ ?xEQ'(UBQ
public CountBean() {} (t&]u7Atr
public void setCountType(String countTypes){ +Go(yS
this.countType=countTypes; [-o`^;
} W}m-5L
public void setCountId(int countIds){ }s)MDq9
this.countId=countIds; }$M 2XF
} ",/3PT
public String getCountType(){ uC\FW6K=m
return countType; KHwzQ<Z3
} 0dS}pd">k
public int getCountId(){ 9~+A<X]Hd
return countId; h(}$-' g
} FTM(y CN
} Z(Da?6#1
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CountCache.java *M5: \+
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/* q6A!xQs<
* CountCache.java wMy$T<:
* '[#a-8-JY_
* Created on 2007年1月1日, 下午5:01 W{E22J}
* n8(B%KF
* To change this template, choose Tools | Options and locate the template under Rz}?@zh_8
* the Source Creation and Management node. Right-click the template and choose (Wkli:Lq
* Open. You can then make changes to the template in the Source Editor. 'Cy^G;
*/ =H*}{'#
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package com.tot.count; *8}Y0V\s
import java.util.*; Hw"ik6
/** }* iag\
* *S_e:^
* @author Gd 0-}4S?
*/ R'a%_sACj>
public class CountCache { j]7|5mC78
public static LinkedList list=new LinkedList(); @rs(`4QEh
/** Creates a new instance of CountCache */ FFXDt"i2
public CountCache() {} TJ(P TB;
public static void add(CountBean cb){ ';`fMcN
if(cb!=null){ /x.TF'Z*
list.add(cb); x4v@Kk/
} 6cof Zc$
} L'{;V\d
} "sLdkd}dj
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CountControl.java ".L+gn}u-
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/* Wz$%o'OnC
* CountThread.java n<MMO=+bg
* 'G6TSl
* Created on 2007年1月1日, 下午4:57 ~^/zCPy[w
* WtI1h `Fo
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose (^GVy=
* Open. You can then make changes to the template in the Source Editor. }C>Q
*/ P# 2&?.d\
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package com.tot.count; PJj{5,#@3
import tot.db.DBUtils; ;ak3@Uee
import java.sql.*; oR}ir
/** xrx{8pf
* #oMbE<//"
* @author l|`FW
*/ ^&<~6y}U^
public class CountControl{ P
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private static long lastExecuteTime=0;//上次更新时间 mOwgk7s[J
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 43rM?_72
/** Creates a new instance of CountThread */ Ku LZg
public CountControl() {} [i[G" %Q
public synchronized void executeUpdate(){ Gb61X6
Connection conn=null; R7*Jb-;$!
PreparedStatement ps=null; %u }|4BXoh
try{ _yjM_ALjo
conn = DBUtils.getConnection(); x6HebIR+
conn.setAutoCommit(false); cb&y8!ci~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); L5T)_iQ5
for(int i=0;i<CountCache.list.size();i++){ HY#7Ctn3
CountBean cb=(CountBean)CountCache.list.getFirst(); ->wY|7
CountCache.list.removeFirst(); Af=%5%
ps.setInt(1, cb.getCountId()); Y=X"YH|
ps.executeUpdate();⑴ wlqV1.K
//ps.addBatch();⑵ E E?v~6"&
}
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//int [] counts = ps.executeBatch();⑶ hx4!P( o1
conn.commit(); 7qE V5!
}catch(Exception e){ > 0 !J]gK
e.printStackTrace(); {%D
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} finally{ N=D
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try{ JmNeqpbB`w
if(ps!=null) { $ajw]2kx
ps.clearParameters(); m?<8 ':
ps.close(); `m<="No
ps=null; Oi
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} XyS#6D
}catch(SQLException e){} ! qrF=a
DBUtils.closeConnection(conn); ]p'Qk
} 8e\a_R*(|
} } Q1$v~
public long getLast(){ v{
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return lastExecuteTime; x(}t r27o
} 5[l3]HOO
public void run(){ ^e@c
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long now = System.currentTimeMillis(); H'gPGOd
if ((now - lastExecuteTime) > executeSep) { #PXl*~PrQ/
//System.out.print("lastExecuteTime:"+lastExecuteTime); o*p7/KvoT
//System.out.print(" now:"+now+"\n"); $L</{bXW
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); YD@V2gK
lastExecuteTime=now; w2{k0MW
executeUpdate(); pvmm" f
} v@>hjie
else{ !YJdi~q
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); e}[$ =
} :@:R4Ac
} ,6t0w|@-k
} yrsP'th
//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 "Wi`S;
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类写好了,下面是在JSP中如下调用。 ?rBj{]=
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<% uU5:,Wy+dg
CountBean cb=new CountBean(); ;uoH+`pf
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); EXJ>Z
CountCache.add(cb); Mqc[IAcd]
out.print(CountCache.list.size()+"<br>"); 5 yA^ n6
CountControl c=new CountControl(); [j93Mp
c.run(); ke3=s
out.print(CountCache.list.size()+"<br>"); N#,4BU
%>