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: R4R\B
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CountBean.java K*2s-,b *
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/* esE!i0%
* CountData.java kX`m(
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* N*6~$zl&
* Created on 2007年1月1日, 下午4:44 Z 4i5,f
* 5Phsh
* To change this template, choose Tools | Options and locate the template under q
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* the Source Creation and Management node. Right-click the template and choose S.B?l_d^
* Open. You can then make changes to the template in the Source Editor. nM:<l}~v{
*/ qV idtSb
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package com.tot.count; 27+faR
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/** !lL
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* a^|9rho<
* @author qyFeq])
*/ b_6cK#
public class CountBean { 7FyE?
private String countType; )=X g
int countId; MffCk!]
/** Creates a new instance of CountData */ QV HI}3~
public CountBean() {} @1&"S7@}u
public void setCountType(String countTypes){ 'J-a2oiM(
this.countType=countTypes; m;hp1VO)
} &+A78I
public void setCountId(int countIds){ I{>Z0+
this.countId=countIds; : _:)S
} %72(gR2Wa2
public String getCountType(){ 8 >LDo"<
return countType; 3**t'iWQ
} G4~@
public int getCountId(){ VF";p^
return countId; L(cKyg[R
} 8#tuB8>
} oF]]Pl{W
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CountCache.java koS?UYF`
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/* &4} =@'G@
* CountCache.java ot2zY
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* 6__!M
* Created on 2007年1月1日, 下午5:01 ILl~f\xG)
* !l0"nPM=
* To change this template, choose Tools | Options and locate the template under nK+ke)'Zv=
* the Source Creation and Management node. Right-click the template and choose ,ayJgAD
* Open. You can then make changes to the template in the Source Editor. 2gkN\w6zQ
*/ !G[%; d
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package com.tot.count; !9YCuHj!p
import java.util.*; ma@V>*u
/** #qF1z}L(
* R) dP=W*
* @author r)Lm| S
*/ &fWC-|
public class CountCache { i^iu#WC
public static LinkedList list=new LinkedList(); CadIux^
/** Creates a new instance of CountCache */ eD2eDxN2
public CountCache() {} nh5=0{va|L
public static void add(CountBean cb){ _izjvg
if(cb!=null){ bEmN
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list.add(cb); bHx@
} D_JGbNigA
} {47l1wV]
} l4U*Lv>
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CountControl.java GH-Fqz
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/* !
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* CountThread.java 9_jiUZFje
* NziCN*6
* Created on 2007年1月1日, 下午4:57 3imsIBr
* pg7~%E4
* To change this template, choose Tools | Options and locate the template under 3(t,x
* the Source Creation and Management node. Right-click the template and choose ~CV.Ci.dG
* Open. You can then make changes to the template in the Source Editor. NQ[X=a8N
*/ ty#6%
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package com.tot.count; YZ8[h`z
import tot.db.DBUtils; >K4Nn(~ys
import java.sql.*; 0&I*)Zt9x
/** z_R^C%0k
* /@1YlxKF
* @author [:gg3Qzx
*/ {5X,xdzR
public class CountControl{ _4L6
private static long lastExecuteTime=0;//上次更新时间 W!O/t^H>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 bQq/~
/** Creates a new instance of CountThread */ l-v m`-_#
public CountControl() {} f
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public synchronized void executeUpdate(){ b/R7Mk1
Connection conn=null; {'wvb
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PreparedStatement ps=null; =fnBE`Uc
try{ n
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conn = DBUtils.getConnection(); aN07\
conn.setAutoCommit(false); >2pxl(i
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); nr
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for(int i=0;i<CountCache.list.size();i++){ et)n`NlcK
CountBean cb=(CountBean)CountCache.list.getFirst(); TB.>?*<n]
CountCache.list.removeFirst(); *'A*!=5(
ps.setInt(1, cb.getCountId()); 'SlZ-SdR
ps.executeUpdate();⑴ 1 /{~t[*.
//ps.addBatch();⑵ h6O'"
} !a:e=b7g
//int [] counts = ps.executeBatch();⑶ 0KgP'oWvY
conn.commit(); V?G%-+^
}catch(Exception e){ T!y 9v5
e.printStackTrace(); d^6-P
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} finally{
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try{ 9d/-+j'
if(ps!=null) { \a|~#N3?
ps.clearParameters(); lGR0-Gh2
ps.close(); EZI#CLT[
ps=null; $<2d|;7r
} SZ[?2z
}catch(SQLException e){} UxHI6,b
DBUtils.closeConnection(conn); aAGV\o{^
} e<9 ^h)G
} I2i'
public long getLast(){ }cCIYt\RK
return lastExecuteTime; &Lt$~}*&6
} 0wVM%Dng
public void run(){ ^Ld5<
long now = System.currentTimeMillis(); #9[>
if ((now - lastExecuteTime) > executeSep) { gM;m{gXYK
//System.out.print("lastExecuteTime:"+lastExecuteTime); /"k [T
//System.out.print(" now:"+now+"\n"); \SQ4yc
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^(C4Q?[2m
lastExecuteTime=now; 3'0vLi
executeUpdate(); >]ux3F3\
} I)` +:+P
else{ ^VMCs/g6
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); "xTVu57Z[
} TS+jDs
} o jxK8_kl
} WLj]EsA.
//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 [@VzpVhXz
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类写好了,下面是在JSP中如下调用。 @Z'i7Z
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<% <^5$))r
CountBean cb=new CountBean(); !xR9I0V5
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); p\;8?x
CountCache.add(cb); j[dZ*Jr_
out.print(CountCache.list.size()+"<br>"); F::Ki4{jJ
CountControl c=new CountControl(); rL"]m_FK
c.run(); }MMKOr(
out.print(CountCache.list.size()+"<br>"); [efU)O&
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