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: y~cDWD<h
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CountBean.java 9ntXLWK7e
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/* `]{/(pIgW;
* CountData.java FD&"k=p+X
* ]i3 1@O
* Created on 2007年1月1日, 下午4:44 T@ [*V[
* 3\xvy{r
* To change this template, choose Tools | Options and locate the template under ,c%>M^d
* the Source Creation and Management node. Right-click the template and choose BihXYux*
* Open. You can then make changes to the template in the Source Editor. |G5Me
*/ *[(}rpp M
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package com.tot.count; U2DE"
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/** _IA@X. )?
* 5,0fL
* @author d{UyiZm\
*/ R(?g+:eCpM
public class CountBean { ~"E@do("
private String countType; rI\G&OqpP
int countId; pV>M,f
/** Creates a new instance of CountData */ qjsS2,wM
public CountBean() {} <_S>- ;by
public void setCountType(String countTypes){ 1]L 0r
this.countType=countTypes; =AhXEu ^
} r*|#*"K"a
public void setCountId(int countIds){ Ut;,Z
this.countId=countIds; ~Bll\3-=
} kvzGI>H:
public String getCountType(){ H]LH~l
return countType; #Z'r;YOzs
} (RP"VEVR
public int getCountId(){ <p<J;@
return countId; n5Ad@B g
} LRqBP|bjCD
} 3x=f}SO&
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CountCache.java s3+^q
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/* Y <'T;@
* CountCache.java |U*wMYC
* Le&SN7I
* Created on 2007年1月1日, 下午5:01 :27GqY,3sK
* -lKk.Y.}r
* To change this template, choose Tools | Options and locate the template under Jww LAQ5
* the Source Creation and Management node. Right-click the template and choose RR u1/nam
* Open. You can then make changes to the template in the Source Editor. \/3Xb
*/ pDGX$1O"
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package com.tot.count; 1gEeZ\B-&
import java.util.*; TA=VfA B
/** K&zp2V
* eIEr\X4\~~
* @author ?0>%
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*/ p`@7hf|hm
public class CountCache { |K(j}^1k
public static LinkedList list=new LinkedList(); FSaCbs(
/** Creates a new instance of CountCache */ -nbo[K
public CountCache() {} W0n/B&C
public static void add(CountBean cb){ ;++CMTza]
if(cb!=null){ teO%w9ByY
list.add(cb); |/u&%w?W
} Mqu>#lL
} n>d@}hyv
} %F'*0<
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CountControl.java 0Q^a*7w`8a
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/* W\V'o Vt
* CountThread.java -e6~0%X
* v7?sXW
* Created on 2007年1月1日, 下午4:57 1]wx Ru
* NwH`t#zd
* To change this template, choose Tools | Options and locate the template under p<5ED\;N;
* the Source Creation and Management node. Right-click the template and choose HmWU;9Vn+
* Open. You can then make changes to the template in the Source Editor. Bnju_)U5)
*/ fAHK<G4
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package com.tot.count; zmV5k
import tot.db.DBUtils; 8!a6)Zeux
import java.sql.*; `Zn2Vx
/** 7X\azL
* 5^"T`,${
* @author Nqih LUv
*/ =.q
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public class CountControl{ GfEg][f
private static long lastExecuteTime=0;//上次更新时间 Rj&V~or
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,2H@xji
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/** Creates a new instance of CountThread */ O>YXvu
public CountControl() {} 6$"gm$3O]
public synchronized void executeUpdate(){ 1
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Connection conn=null; 9$-V/7@)
PreparedStatement ps=null; m'|{AjH
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try{ yDwG,)m 4s
conn = DBUtils.getConnection(); 9EryHV|
conn.setAutoCommit(false); ,uEi*s>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); C]22 [v4
for(int i=0;i<CountCache.list.size();i++){ crV2T
CountBean cb=(CountBean)CountCache.list.getFirst(); NXQdy g,
CountCache.list.removeFirst(); d,r%LjNI
ps.setInt(1, cb.getCountId()); |Qq_;x]
ps.executeUpdate();⑴ `^t0379e
//ps.addBatch();⑵ 3GkVMYI
} D8u_Z<6IjI
//int [] counts = ps.executeBatch();⑶ IuJj;L1
conn.commit(); ZJL[#}*
}catch(Exception e){ Jf<+VJ>t
e.printStackTrace(); SKx&t-
} finally{ ?eUhHKS5
try{ XdKhT61 8G
if(ps!=null) { a?]Ow J
ps.clearParameters(); OidF{I*O
ps.close(); XWQp-H.
ps=null; k _)H$*
} MV"aO@
}catch(SQLException e){} F\1{b N|3
DBUtils.closeConnection(conn); 7r=BGoA2E
} ;U6z|O7L
} :Gyv%>.
public long getLast(){
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return lastExecuteTime; !C&!Wj
} FsrGI
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public void run(){ c hE~UQ
long now = System.currentTimeMillis(); b"-eQb
if ((now - lastExecuteTime) > executeSep) { 4%#C _pE9
//System.out.print("lastExecuteTime:"+lastExecuteTime); u@v0I$
//System.out.print(" now:"+now+"\n"); 2"
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); I4%&/~!
lastExecuteTime=now; tWkD@w`Lnn
executeUpdate(); 2+pLDIIT
} V!=1 !"}OG
else{ 9o7E/wP
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g0@i[&A@{
} Fwn4c4-%
} [([?+Ouy
} nKn,i$sO/.
//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 31b9pi}nf
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类写好了,下面是在JSP中如下调用。 E]PHO\f-m}
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<% T9enyYt%
CountBean cb=new CountBean(); R3;GMe@D#
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =
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CountCache.add(cb); `PI,tmv!
out.print(CountCache.list.size()+"<br>"); ;5tSXgGw7
CountControl c=new CountControl(); |1`|E-S=
c.run(); F5Tah{
out.print(CountCache.list.size()+"<br>"); JCNZtWF
%>