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: =
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CountBean.java z6U'"T"a
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/* \C$e+qb~{
* CountData.java ^>an4UJt
* B]tj0FB`-*
* Created on 2007年1月1日, 下午4:44 /!0&b?
* Xb:*
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* To change this template, choose Tools | Options and locate the template under kKlNhP(
* the Source Creation and Management node. Right-click the template and choose -ZE YzZqY
* Open. You can then make changes to the template in the Source Editor. qfXt%6L
*/ {{G3^ysa
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package com.tot.count; iYB c4'X
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/** )yyH_Ax2
* R{c~jjd
* @author =l:V9u-I^
*/ !@lx|=#
public class CountBean { a!bW^?PcK
private String countType; U Y*`R
int countId; BR|0uJ.M
/** Creates a new instance of CountData */ ].rKfv:
public CountBean() {} j-BNHX
public void setCountType(String countTypes){ JL
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this.countType=countTypes; C')KZ|JIC
} %JDQ[%3qY
public void setCountId(int countIds){ L|WrdT D;
this.countId=countIds; GcN}I=4|
} nam]eW
public String getCountType(){ Jw5@#j
return countType; YT?Lt!cl=
} g^
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public int getCountId(){ atpHv**D<i
return countId; '1DY5`i{
} Mlc_w19C9
} a0)w/A&
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CountCache.java k}:;`ST
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/* lZRO"[<
* CountCache.java 3U^Vz9LW
* j~Pwt9G
* Created on 2007年1月1日, 下午5:01 [<,7LG<
* DX! dU'tj
* To change this template, choose Tools | Options and locate the template under FbuWFC
* the Source Creation and Management node. Right-click the template and choose <5%*"v
* Open. You can then make changes to the template in the Source Editor. 0V-jOc
*/ odca?
jR}EBaI}
package com.tot.count; /1Gmga5
import java.util.*; #W8F_/!n|
/** c/88|k
* JYj*.Q0
* @author e1XKlgl
*/ FR6 W-L
public class CountCache { 6I RRRt O(
public static LinkedList list=new LinkedList(); GXm#\)
/** Creates a new instance of CountCache */ >"IG\//I
public CountCache() {} ym5@SBqIx
public static void add(CountBean cb){ -3yK>\y=|
if(cb!=null){ 5 ph CEKt;
list.add(cb); Q&PWW#D
} @+t|Aa^g
} 6h5g!GQD
} t0fgG/f'
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CountControl.java q}p$S2`
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/* ?ch?q~e)
* CountThread.java oU,8?(}'~
* 9O&m7]3
* Created on 2007年1月1日, 下午4:57 oJNQdW[
* L/Kb\\f
* To change this template, choose Tools | Options and locate the template under ,
poc!n//
* the Source Creation and Management node. Right-click the template and choose ]#4kqj}
* Open. You can then make changes to the template in the Source Editor. !X: TieyVu
*/ SrNc
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package com.tot.count; VDOC>
import tot.db.DBUtils; @7"n X
import java.sql.*; >Z*b0j
/** !G vT{
* [xY-=-T*4
* @author ~q+AAWL
*/ DcFY b|p
public class CountControl{ DqY"N]
private static long lastExecuteTime=0;//上次更新时间 l"JM%LV
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @ NDcO,]
/** Creates a new instance of CountThread */ K:-jn}i?/
public CountControl() {} ~D5FnN9
public synchronized void executeUpdate(){ ]:@{tX7c
Connection conn=null; m4h)Wq
PreparedStatement ps=null; An#[
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try{ Y?1T
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conn = DBUtils.getConnection(); ZzBaYoNy[0
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); V?*fl^f
for(int i=0;i<CountCache.list.size();i++){ v+x rnz
CountBean cb=(CountBean)CountCache.list.getFirst(); 8J&9}@y
CountCache.list.removeFirst(); z[ ;n2o|s
ps.setInt(1, cb.getCountId()); nLAwo3
ps.executeUpdate();⑴ [4C_iaE
//ps.addBatch();⑵ 2k=|p@V n~
} Has}oe[
//int [] counts = ps.executeBatch();⑶ }R}M>^(R4
conn.commit(); 6oQ7u90z*
}catch(Exception e){ O[$X36z
e.printStackTrace(); n~
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} finally{ N:Q.6_%^
try{ 0sSBwG
if(ps!=null) { QZ(O2!Mg
ps.clearParameters(); ~sn3_6{
ps.close(); NG3:=
ps=null; >A]l|#Rz
} #t1? *4.p
}catch(SQLException e){} jTqJ(M}L
DBUtils.closeConnection(conn); EP;ts
} c{to9Lk.#
} Cp!9 "J:
public long getLast(){ ~)$R'=
return lastExecuteTime; VJ'-"8tY&
} jqvw<+#
public void run(){ ~}p k^FA
long now = System.currentTimeMillis(); E`HA0/
if ((now - lastExecuteTime) > executeSep) { s\3]0n9
//System.out.print("lastExecuteTime:"+lastExecuteTime); `Ivt)T+n;
//System.out.print(" now:"+now+"\n"); h*KDZ+{)
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); A #SO}c
lastExecuteTime=now;
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executeUpdate(); 9wc\~5{li
} =>>Dnp
else{ K)l*$h&-
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); D`Vb3aNB=L
} #p;<X|Hc}8
} 2=fLb7
} LjGLi>kI~
//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 GCQOjqiR
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类写好了,下面是在JSP中如下调用。 M@q)\UQ'
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<% kz1Z K
CountBean cb=new CountBean(); i)cG
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); n&]J-^Tx
CountCache.add(cb); Z>w@3$\z
out.print(CountCache.list.size()+"<br>"); B
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CountControl c=new CountControl(); hC{2LLu;n
c.run(); q4@+Pi)
out.print(CountCache.list.size()+"<br>"); -$%~EY}
%>