Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 #vh1QV!Ho
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 JA0$Fz
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 $Gt1T[:QUX
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 }%LwaRT
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分页支持类: GtI]6t
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java代码: u=^0n2ez
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package com.javaeye.common.util; l*]9
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import java.util.List; k<W n
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publicclass PaginationSupport { 2_Me
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publicfinalstaticint PAGESIZE = 30; $__e7
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privateint pageSize = PAGESIZE; _\yrR.HIa
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privateList items; qT]Bl+h2
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privateint totalCount; Yc;cf%c1
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privateint[] indexes = newint[0]; tMGkm8y-A
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privateint startIndex = 0; 47I5Y5
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public PaginationSupport(List items, int J]uYXsC
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totalCount){ ?m-kpW8
setPageSize(PAGESIZE); Y68`B"3
setTotalCount(totalCount); 9HMW!DSK`
setItems(items); mY"DYYR>
setStartIndex(0); lS P{9L6
} d5<@WI:wz
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public PaginationSupport(List items, int YbZ<=ZzO4
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totalCount, int startIndex){ EN@LB2
setPageSize(PAGESIZE); BcV;EEi
setTotalCount(totalCount); Yh/-6wg
setItems(items); $$YLAgO4
setStartIndex(startIndex); 4/D~H+k
} v8g3]MVj3
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public PaginationSupport(List items, int B.fLgQK0
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totalCount, int pageSize, int startIndex){ Bu?"b=B*
setPageSize(pageSize); DJgk"'
setTotalCount(totalCount); (?-5p;
setItems(items); wqo2iRql
setStartIndex(startIndex); ?QO)b9
} Re?sopg0r
@(.?e<
publicList getItems(){ (zkh`8L
return items; 01I5,Dm
} N3^pFy`
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publicvoid setItems(List items){ }8WpX2U
this.items = items; #r 1
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} z79L2lJn
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publicint getPageSize(){ cqeId&Cg
return pageSize; G-oCA1UdN
} b><jhbv
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publicvoid setPageSize(int pageSize){ #f]R:Ix>
this.pageSize = pageSize; gUDd2T#
} EVmQ"PKL'
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publicint getTotalCount(){ K/oPfD]
return totalCount; 'T[=Uuj"
} q|2{W.P5qi
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publicvoid setTotalCount(int totalCount){ 1DcYc-k#
if(totalCount > 0){ Y>!9P\Xe
this.totalCount = totalCount; #m
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int count = totalCount / "d'xT/l
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pageSize; G1B~?i2$ ?
if(totalCount % pageSize > 0) FsZM_0>/s
count++; ,G1|]
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indexes = newint[count]; Y">tfLIL_
for(int i = 0; i < count; i++){ |w[}\#2
indexes = pageSize * R@>R@V>c
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} y<PPO6u7
}else{ d T/*O8
this.totalCount = 0; XRs/gUT
} Ed#%F-1sX
} O89<IXk
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publicint[] getIndexes(){ `ZN@L<I6
return indexes; =Z/'|;Vd_x
} ` 2|~Z
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publicvoid setIndexes(int[] indexes){ -a3+C,I8g
this.indexes = indexes; fh$U"
} En6fmEn&;o
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publicint getStartIndex(){ W_8FzXA
return startIndex; 05*_h0}
} 'DsfKR^s
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publicvoid setStartIndex(int startIndex){ SrK;b .
if(totalCount <= 0) bXq,iX
this.startIndex = 0; 2 T{PIJg3
elseif(startIndex >= totalCount) \,
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this.startIndex = indexes BO[Q"g$Kon
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[indexes.length - 1]; Djf2ir'
elseif(startIndex < 0) dG7sY
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this.startIndex = 0; /dOQ4VA\
else{ =i%2/kdi0b
this.startIndex = indexes WbH/K]/1)h
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[startIndex / pageSize]; pY =?r{@
} NL&g/4A[a
} l[G,sq"
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publicint getNextIndex(){ k`)LO`))
int nextIndex = getStartIndex() + M#S8x@U
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pageSize; F]yclXf('
if(nextIndex >= totalCount) c'`7p/l.
return getStartIndex(); |nry^zb
else w0/W=!_
return nextIndex; l$m^{6IYc
} Zy*}C,Z
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publicint getPreviousIndex(){ w#PaN83+
int previousIndex = getStartIndex() - ~ezCE4^&
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pageSize; " "a+Nc
if(previousIndex < 0) fY%Sw7ql<
return0; NBMY1Xgj
else yvDzxu
return previousIndex; 4vqu(w8
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} T>f-b3dk
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} S"3g 1yU^_
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抽象业务类 Bl`e+&b
java代码: 6w1:3~a
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/** H8\{GGg
* Created on 2005-7-12 r456M-~
*/ _%1.D0<~-E
package com.javaeye.common.business; yAi4v[
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import java.io.Serializable; |=%$7b\C
import java.util.List; a}>GQu*y
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import org.hibernate.Criteria; |um)vlN;9
import org.hibernate.HibernateException; uDoSe^0
import org.hibernate.Session; fs)O7x-B(
import org.hibernate.criterion.DetachedCriteria; f4tia.
import org.hibernate.criterion.Projections; n<hwstk
import Ue,"CQ6H
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org.springframework.orm.hibernate3.HibernateCallback; , JZ@qmQ,
import $(CHwG-
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org.springframework.orm.hibernate3.support.HibernateDaoS sJM}p5V
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upport; UT{Nly8u
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import com.javaeye.common.util.PaginationSupport; _v$mGZpGY
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public abstract class AbstractManager extends 4P:vo $Cy
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HibernateDaoSupport { "V:UQ<a\
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privateboolean cacheQueries = false; ih YfWG|
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privateString queryCacheRegion; Xif`gb6`
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publicvoid setCacheQueries(boolean #F{|G:\@[
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cacheQueries){ f
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this.cacheQueries = cacheQueries; jcG4h/A
} 5
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publicvoid setQueryCacheRegion(String [R:O'AP}@}
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queryCacheRegion){ ftH
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this.queryCacheRegion = B " B
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queryCacheRegion; .-34g5
} d[Fsp7U}
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publicvoid save(finalObject entity){ e| l?NXRX
getHibernateTemplate().save(entity); j68Gz5;j
} hs*:!&E
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publicvoid persist(finalObject entity){ T(}da**X
getHibernateTemplate().save(entity); kN) pi "
} %FRkvqV*
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publicvoid update(finalObject entity){ ~G$OY9UC
getHibernateTemplate().update(entity); "l@~WE
} 0y1t%C075
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publicvoid delete(finalObject entity){ +I~?8*
getHibernateTemplate().delete(entity); 6x7=0}'
} u}h'v&"e,
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publicObject load(finalClass entity, \G"/Myi
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finalSerializable id){ Zu hT \l
return getHibernateTemplate().load tO0+~Wm
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(entity, id); G?g7G,|d
} YS~x-5OE\
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publicObject get(finalClass entity, 0qZ)$YKq
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finalSerializable id){ Nl8Cctrf
return getHibernateTemplate().get
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(entity, id); oe<Y,%u"6
} hh{liS% 10
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publicList findAll(finalClass entity){ (M=Br
return getHibernateTemplate().find("from uXC?fMWp.
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" + entity.getName());
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}
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publicList findByNamedQuery(finalString lyPXlt
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namedQuery){ }:irjeI,
return getHibernateTemplate |)_R
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().findByNamedQuery(namedQuery); &Y>u2OZ
} +OmSR*fA0
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publicList findByNamedQuery(finalString query, vOS0E^
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finalObject parameter){ `iI"rlc
return getHibernateTemplate nXS%>1o,
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().findByNamedQuery(query, parameter); +NY4j-O
} ]3,0
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publicList findByNamedQuery(finalString query, *X #e
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finalObject[] parameters){ P(;c`
return getHibernateTemplate ,W-0qN&%/
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().findByNamedQuery(query, parameters); g2]-Q.
} O /&%`&2
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publicList find(finalString query){ ""d>f4,S
return getHibernateTemplate().find a3 x~B=E
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(query); X
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} z,)sS<t(
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publicList find(finalString query, finalObject h~@+M5r,
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parameter){ ni>
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return getHibernateTemplate().find NjxW A&[ng
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(query, parameter); g@k9w{_
}
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public PaginationSupport findPageByCriteria (0Cszm.
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(final DetachedCriteria detachedCriteria){ 4QNR_w
return findPageByCriteria ->8q, W2A
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); r\d:fot
} q#`^EqtUF
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public PaginationSupport findPageByCriteria -#6*T,f0P(
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(final DetachedCriteria detachedCriteria, finalint ];;w/$zke
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startIndex){ W<VHv"?V
return findPageByCriteria BT3O_X`u
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(detachedCriteria, PaginationSupport.PAGESIZE, (Y)h+}n5N
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startIndex); ]LTc)[5Zj
} <h=M
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public PaginationSupport findPageByCriteria c!Vc_@V,
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(final DetachedCriteria detachedCriteria, finalint S(i(1Hs.
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pageSize, Ba0D"2CgY
finalint startIndex){ h\d($Ki
return(PaginationSupport) PEEY;x
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getHibernateTemplate().execute(new HibernateCallback(){ sjgR \`AU
publicObject doInHibernate ZPao*2xz
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(Session session)throws HibernateException { |:+pPh!-
Criteria criteria = i(;-n_:,`
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detachedCriteria.getExecutableCriteria(session); r5!M;hU1j
int totalCount = rVy\,#|
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((Integer) criteria.setProjection(Projections.rowCount q&Wwtqc9
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()).uniqueResult()).intValue(); p,\bez
criteria.setProjection {K4t8T]
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(null); tcEf
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List items = lO> 7`2x=F
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criteria.setFirstResult(startIndex).setMaxResults ' u};z:t
Az9J{)
(pageSize).list(); &6=ZT:.6Te
PaginationSupport ps = #0^3Wm`X;
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new PaginationSupport(items, totalCount, pageSize, 8'"/gC{
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startIndex); NoZ4['NI\
return ps; :TYzzl43
} 8;\tP29
}, true);
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} KH>sCEt
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public List findAllByCriteria(final 3dDQz#
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DetachedCriteria detachedCriteria){ irb.F>(x
return(List) getHibernateTemplate u6I0<i_KZ
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().execute(new HibernateCallback(){ W?J*9XQ`
publicObject doInHibernate ioa_AG6B
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(Session session)throws HibernateException { G!LNP&~
Criteria criteria = dzNaow*0&V
PB<Sc>{U
detachedCriteria.getExecutableCriteria(session); N|d.!Q;V.y
return criteria.list(); a 8hv .43
} (Zn3-t*
}, true); 7W firRM
} 9Q7cUoxY
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public int getCountByCriteria(final | ,l=v`/
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DetachedCriteria detachedCriteria){ n[:AV
Integer count = (Integer) Q0uO49sg
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getHibernateTemplate().execute(new HibernateCallback(){ m\Fb ,
publicObject doInHibernate 5`'au61/2
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(Session session)throws HibernateException { MY*>)us\
Criteria criteria = +6)kX4
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detachedCriteria.getExecutableCriteria(session); &Yks,2:P
return f.84=epv
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criteria.setProjection(Projections.rowCount 27YLg c
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()).uniqueResult(); dms:i)L2
} X.AWs=:-
}, true); 'j<:FUDJ
return count.intValue(); [(P[qEY
} <\9Ijuq}k
} \
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用户在web层构造查询条件detachedCriteria,和可选的 ocA'goI-
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 a2=uM}Hsp
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PaginationSupport的实例ps。 )>X|o$2
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ps.getItems()得到已分页好的结果集 g*r{!:,t
ps.getIndexes()得到分页索引的数组 #b"5L2D`y'
ps.getTotalCount()得到总结果数 =.f +}y
ps.getStartIndex()当前分页索引 'oHOFH9:{b
ps.getNextIndex()下一页索引 XG\a-dq[
ps.getPreviousIndex()上一页索引 }!yD^:[5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 <j1d~XU}
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 NtA|#"^
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一下代码重构了。 Z>w^j.(
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我把原本我的做法也提供出来供大家讨论吧: .1z$ A
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首先,为了实现分页查询,我封装了一个Page类: D@rn@N
java代码: ! N"L`RWD
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/*Created on 2005-4-14*/ Q1ABnacR
package org.flyware.util.page; }2BH_
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/** [,o5QH\Etq
* @author Joa v1X&p\[d
* r@ T-Hi
*/ &W)+8N,L
publicclass Page { [;IDTo!<>
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/** imply if the page has previous page */ y5AXL5
privateboolean hasPrePage; +%le/Pg@
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/** imply if the page has next page */ \A3>c|
privateboolean hasNextPage; /!{A=N
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/** the number of every page */ vA"`0
privateint everyPage; #EQx
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/** the total page number */ VNxpOoV=S
privateint totalPage; A"bSNHCKF
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/** the number of current page */ 5;K-,"UQ
privateint currentPage; 74}eF)(me
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/** the begin index of the records by the current WDoKbTv
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query */ 5}d/8tS
privateint beginIndex; SN[L4}{
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/** The default constructor */ y[^k*,=
9
public Page(){ /50g3?X,
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} _86*.3fQG
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/** construct the page by everyPage &Xn8oe
* @param everyPage V'Z&>6Z
* */ 68J 9T^84
public Page(int everyPage){ /XW&q)z-Hl
this.everyPage = everyPage; 8=n9hLhqo
} lZS_n9Sc
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/** The whole constructor */ >TlW]st
public Page(boolean hasPrePage, boolean hasNextPage, bQ^DX `o6P
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int everyPage, int totalPage, |Uy e>%*}4
int currentPage, int beginIndex){ OZ>)sL
this.hasPrePage = hasPrePage; u6iU[5
this.hasNextPage = hasNextPage; 56bud3CVs
this.everyPage = everyPage; EZ%w=
this.totalPage = totalPage; *793H\
this.currentPage = currentPage; T]Tdx.B
this.beginIndex = beginIndex; , N@Yk.
} x!"SD3r=4>
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/** L=
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* @return S/nj5Lh
* Returns the beginIndex. ;LQ# *NjL\
*/ l\T!)Ql
publicint getBeginIndex(){ I+Ncmg )>
return beginIndex; Xx3g3P
} w'oo-.k
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/** J0ZxhxX35
* @param beginIndex XSm"I[.g
* The beginIndex to set. wQD0vsD
*/ 9lZAa8Rx i
publicvoid setBeginIndex(int beginIndex){ nOAJ9
this.beginIndex = beginIndex; fr}1_0DDz
} ,?xLT2>J_
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/** Z>(r9R3{
* @return z.2r@Psk
* Returns the currentPage. E[|s>Xv~
*/ %]a
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publicint getCurrentPage(){ k#axt
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return currentPage; Snc;p
} 93W
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/** .>mH]/]m
* @param currentPage ]>R`;"(
* The currentPage to set.
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*/ g.B%#bfg
publicvoid setCurrentPage(int currentPage){ j4~7akG
this.currentPage = currentPage; >63)z I
} >lD;0EN
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/** Q0zW ]a
* @return {fGd:2dh
* Returns the everyPage. \H Wcd|
*/ EJf #f
publicint getEveryPage(){ :]P~.PD5,
return everyPage; _BZ1Vnv
} CQ6'b,L&
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/** q"gqO%Wb|
* @param everyPage qP~WEcH`[
* The everyPage to set. ,?l~rc
*/ _j:UGMTi(U
publicvoid setEveryPage(int everyPage){ ;{<aA 5
this.everyPage = everyPage; V]I:2k5
} ?PBa'g
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/** uh]"(h(>
* @return Bk?8zYp
* Returns the hasNextPage. T
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*/ ,:D=gQ@`
publicboolean getHasNextPage(){ a}:A, t<6
return hasNextPage; v8ba~
} 2
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/** '3A+"k-}mh
* @param hasNextPage 2O
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* The hasNextPage to set. K(<$.
*/ 8zhBA9Y#~
publicvoid setHasNextPage(boolean hasNextPage){ y }\r#"Z`
this.hasNextPage = hasNextPage; x^A7'ad0
} ""co6qo#>
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/** >\V6+$cNp
* @return ]UDd :2yt
* Returns the hasPrePage. q[7CPE0n
*/ 9<yAQ?7L
publicboolean getHasPrePage(){ rh@r\H@j
return hasPrePage; 0,HqE='w
} %BUEX
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/** QE|`&~sme
* @param hasPrePage S_J,[#&
* The hasPrePage to set. aF!E x
*/ b"I~_CL|
publicvoid setHasPrePage(boolean hasPrePage){ LO)GTyzvJ
this.hasPrePage = hasPrePage; {Fbg]'FQ
} ]eE 1n2
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/** P0^c?s"I
* @return Returns the totalPage. RctU' T
* |,b2b2v?
*/ zj<ahg%z
publicint getTotalPage(){ \V,c]I
return totalPage; "!O1j
r;
} |^R*4;Phe
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/** m`z7fi7u
* @param totalPage /
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* The totalPage to set. e@E17l-
*/ dL-i)F
publicvoid setTotalPage(int totalPage){ ~.J,A\F
this.totalPage = totalPage; tJNIr5o
} zh\$t]d<I
4o<*PPA1
} w5`#q&?
CE uWw:)
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# ly@;!M
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 OF[?Z
mzWP8Hlw
个PageUtil,负责对Page对象进行构造: l
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java代码: N2BI_,hI1
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/*Created on 2005-4-14*/ t2-
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package org.flyware.util.page; ,M QVE
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import org.apache.commons.logging.Log; #EDEYEW7
import org.apache.commons.logging.LogFactory; 9Hd;353Q
=. *98
/** `1Zhq+s
* @author Joa B:<
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* y`yZR
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*/ U&UKUACn"
publicclass PageUtil { 44\cI]!{
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privatestaticfinal Log logger = LogFactory.getLog WF2NG;f=
rAb&I"\ZY
(PageUtil.class); >O#grDXb
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/** 2?W7I/F
* Use the origin page to create a new page 5r b-U7 /
* @param page ZtK\HDdp
* @param totalRecords Gh}yb-$N`&
* @return o:"anHs
*/ 9xFO]Y"
publicstatic Page createPage(Page page, int Pao%pA.<
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totalRecords){ wG1l+^p
return createPage(page.getEveryPage(), Ts9ktPlm
z
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page.getCurrentPage(), totalRecords); "7,FXTaer
} d--'Rn5
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/** JN4fPGbV
* the basic page utils not including exception {^}0 G^
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handler :=Kx/E:1
* @param everyPage n((vY.NDV
* @param currentPage $bvJTuw
* @param totalRecords ,lt8O.h-l
* @return page t9^A(Vh"-
*/ FY'ty@|_s
publicstatic Page createPage(int everyPage, int 2 rN ,D(
"B{ECM;
currentPage, int totalRecords){ 0:=ZkEEeU
everyPage = getEveryPage(everyPage); Wh(
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currentPage = getCurrentPage(currentPage); x[Im%k
int beginIndex = getBeginIndex(everyPage, o31Nmy
Ni
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currentPage); H={&3poBz
int totalPage = getTotalPage(everyPage, ;apzAF
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totalRecords); Wht(O~F
boolean hasNextPage = hasNextPage(currentPage, ;@3FF
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totalPage); wW 2d\Zd&
boolean hasPrePage = hasPrePage(currentPage); ~Rpm-^
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returnnew Page(hasPrePage, hasNextPage, P[ r];e
everyPage, totalPage, 47r&8C+&\
currentPage, f )Z%pgB
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beginIndex); pI.+"Hz
} =IU*}>#
\.uc06
privatestaticint getEveryPage(int everyPage){ w Q+8\ s=
return everyPage == 0 ? 10 : everyPage; lFSe?X^
} "*z_O
@U{<a#
privatestaticint getCurrentPage(int currentPage){ &a,OfSz
return currentPage == 0 ? 1 : currentPage; 52_#
} a4MZ;5
r?/A?DMe
privatestaticint getBeginIndex(int everyPage, int TUIk$U?/I
1f'Hif*r_X
currentPage){ Wg`AZ=t
return(currentPage - 1) * everyPage; tK(g-u0N`(
} ^|!I+
c{+A J8
privatestaticint getTotalPage(int everyPage, int 5O/i3m26
I1Sa^7
totalRecords){ %+)o'nf"U
int totalPage = 0; @}-r&/#
->^~KVh&
if(totalRecords % everyPage == 0) h#r^teui)
totalPage = totalRecords / everyPage; \2 y5_;O
else kq=V4-a[
totalPage = totalRecords / everyPage + 1 ; FQz?3w&ia
a:,y
Z
return totalPage; zSEs?
} )D&M2CUw"f
8~lIe:F-
privatestaticboolean hasPrePage(int currentPage){ ~ PWSo%W8
return currentPage == 1 ? false : true; U69u'G:
} =&wmWy
LhXUm
privatestaticboolean hasNextPage(int currentPage, g*UMG>
%+>s#Q2d
int totalPage){ %xZG*2vc!B
return currentPage == totalPage || totalPage == }@1q@xU
I){\0vb@
0 ? false : true; U9y|>P\)T
} JA)?p{j
tR0pH8?e"
z4#(Ze@u~_
} ?~"bR%
GNf 482
fWc|gq
;22l"-F
j(:I7%3&(*
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 h^9"i3H
%@a8P
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 K;hh&sTB
F~:O.$f]G
做法如下: ?3ig)J,e[
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 w]b,7QuNz
0Sq][W=
的信息,和一个结果集List: '>$EOg"
java代码: X,aYK;q%z
\0l>q ,
U[L9*=P;
/*Created on 2005-6-13*/ VGHWNMT
package com.adt.bo; s>k Uh
7|\@zQ h
import java.util.List; I:bD~Fb3
vu!d)Fy
import org.flyware.util.page.Page; n79QJl/
p.I.iAk%G^
/** 7(M(7}EKA
* @author Joa w=]Ks'C]
*/ $Nrm!/)*'}
publicclass Result { <~TP#uAz
pLa[}=
private Page page; !Cgx.
" 96yp4v@
private List content; Jd\apBIf
ih,%i4<}6m
/** ah
@uUHB
* The default constructor :@W.K5
*/ NNhL*C[_7
public Result(){ Xs&TJ8a
super(); Pq*s{
} V.ht,
~l
@`tXKP$so
/** >Vy>O&r
* The constructor using fields 21s4MagC
* UYk>'\%H0
* @param page `l2O?U -@
* @param content ?
J}r
*/ !US d9
public Result(Page page, List content){ 8}H1_y-g[
this.page = page; ?D,=37
this.content = content; Om{l>24i.\
} b'MSkEiQG
X[#zCM
/** M8H5K
* @return Returns the content. +^*iZ6{+7
*/ PJxH7|GSi
publicList getContent(){ 5@*'2rO&!
return content; Hf'G8vW
} D7Y)?Z5A;
K{n{KB&_&
/** m9U"[Huv1E
* @return Returns the page. x21dku<6K[
*/ p!]6ll^
public Page getPage(){ ]yjl~3
return page; 9/+Nj /
} :o:e,WKxb
$^u}a
/** go+Q~NV
* @param content UobyK3.%
* The content to set. H|cNH=
*/ pg]BsJN
public void setContent(List content){ ,-x!$VqS
this.content = content; OD']:
} $$:ZX
$/6;9d^
/** BCe_@
* @param page G'YH6x,
* The page to set. omWJJ|b~
*/ ikE<=:pe
publicvoid setPage(Page page){ u77E! z4Uz
this.page = page; vI$t+m:
} %| G"-%_E
} Ax !+P\\2~
!`!| Zw
~Lc066bLeq
Y+K|1r
cYXM__
2. 编写业务逻辑接口,并实现它(UserManager, /1?R?N2>0
@HZKc\1
UserManagerImpl) r`c_e)STO
java代码: >0p$(>N]
}j,[ 1@S
$gBd <N9|c
/*Created on 2005-7-15*/ jx Jv.
package com.adt.service; }|%eCVB
L
8{\r$
import net.sf.hibernate.HibernateException; P/&]?f0/
''\;z<v
import org.flyware.util.page.Page; {'16:dTJ
'!f5?O+E
import com.adt.bo.Result; R |KD&!~Z
rJ KZ)N{
/** 5NJ4
* @author Joa hzk6rYg1
*/ k6=nO?$
publicinterface UserManager { `9k0Gd
0Z{j>=$
public Result listUser(Page page)throws <F11m(
!n6wWl
HibernateException; /b|0PMX
?xK,mbFgl
} fO#vF.k%
LJoGpr8
e8'wG{3A
~
ihI_q"
,vW:}&U
java代码: pLv$\MiZ
a<]B B$~
g/13~UM\
/*Created on 2005-7-15*/ I(=V}s2
package com.adt.service.impl; *%KKNT'*
2w)-\/j}
import java.util.List; >
xIJE2
tH'2gl
import net.sf.hibernate.HibernateException; YJ(*wByM
lsN~*q?~]
import org.flyware.util.page.Page; 02BuX]_0g
import org.flyware.util.page.PageUtil; |d6T/Uxo
:_M;E"9R
import com.adt.bo.Result; d;n."+=[x
import com.adt.dao.UserDAO; Q]p(u\*
import com.adt.exception.ObjectNotFoundException; a#T]*(Yq)
import com.adt.service.UserManager; Nan[<
d\|!Hg,
/** %e&9.
* @author Joa V]90
*/ v9T_&
publicclass UserManagerImpl implements UserManager { v@# b}N0n
3]?#he
private UserDAO userDAO; HYmn:?H
<V>dM4Mkr
/** pKi& [
* @param userDAO The userDAO to set. svXR<7)#
*/ ws^4?O
publicvoid setUserDAO(UserDAO userDAO){ ^_lzZOhG
this.userDAO = userDAO; !Ra*)b"
} %u;~kP|S%
r_;9'#&'
/* (non-Javadoc) <id}<H
* @see com.adt.service.UserManager#listUser
^eoLAL
s=[h?kB
(org.flyware.util.page.Page) F`9]=T0
*/ U!Ek'
public Result listUser(Page page)throws H:"maS\I
ul*Qt}
HibernateException, ObjectNotFoundException { )Pv9_XKJ
int totalRecords = userDAO.getUserCount(); 2h%z ("3/
if(totalRecords == 0) @O[5M2|r
throw new ObjectNotFoundException
YtO|D
H*9~yT'Q
("userNotExist"); @Vu(XG
page = PageUtil.createPage(page, totalRecords); MX+Z ?
List users = userDAO.getUserByPage(page); |\n_OS7
returnnew Result(page, users); N<DGw?Rl
} \(%Y%?dy
#h/Mbj~S
} )XWP\
h
|.wEm;Bz
DfKr[cqLM
`7H4Y&E
yeHDa+}
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 VWO9=A*Y|
o: ;"w"G
询,接下来编写UserDAO的代码: ;,]P=Ey
3. UserDAO 和 UserDAOImpl: zz& ?{vJ
java代码: cYqfsd# B
,*7d
-ig6w.%lk
/*Created on 2005-7-15*/ _2N$LLbg
package com.adt.dao; D1&A,2wO
<\;#jF%V
import java.util.List; 1T[et-
&d|r~NhP
import org.flyware.util.page.Page; (64yg
!fj(tPq
import net.sf.hibernate.HibernateException; ZI=v.wa
<ZB1Vi9}8
/** 5YrBW:_OI
* @author Joa }*L(;r)q
*/ <qGu7y"
publicinterface UserDAO extends BaseDAO { Q~T$N
{P*m;a`}
publicList getUserByName(String name)throws |7zd%!
3$X'Y]5a
HibernateException; HbW0wuI
'}$Dgp6e
publicint getUserCount()throws HibernateException; N$[{8yil^w
\<g*8?yFs
publicList getUserByPage(Page page)throws p}cw{
NQ6sGL
HibernateException; k-}b{
xt*u4%
} ~*wk6&|
{D=@n4JO
`]W|8M
nvPwngEQm
q`r**N+zn
java代码: l'eyq}&
8w.YYo8`
RU\/j%^
/*Created on 2005-7-15*/ =AuR:Tx
package com.adt.dao.impl; Hhh0T>gi
KRA/MQ^7~U
import java.util.List; _F`lq_C
bcYF\@};
import org.flyware.util.page.Page; [ 1u-Q%?#
Gn&4V}F
import net.sf.hibernate.HibernateException; !@v7Zu43,
import net.sf.hibernate.Query; p3^m9J
ynrT a..
import com.adt.dao.UserDAO; }+sT4'Ah>
Er{>p|n=
/** yNTK .
* @author Joa 15sp|$&`
*/ lg&t8FHa;
public class UserDAOImpl extends BaseDAOHibernateImpl &c,kQo+pA
*Em,*!
implements UserDAO { ^N)R=tl
gdQvp=v]
/* (non-Javadoc) zO iu5
* @see com.adt.dao.UserDAO#getUserByName 1Yn
+<I
S.f5v8
(java.lang.String) Pjc
Tx +
*/ .qZI$
l.
publicList getUserByName(String name)throws f=9|b
qXwPDq/
HibernateException { r%+V8o
String querySentence = "FROM user in class Dg?:/=,=9r
Bf8jPa/
com.adt.po.User WHERE user.name=:name"; v%iflCK
Query query = getSession().createQuery \:UIc*S
@qYp>|AF
(querySentence); [;J>bi;3N
query.setParameter("name", name); @
rc{SB
return query.list(); %B.yW`,X
} %xyou:~0zs
K9up:.{QQ
/* (non-Javadoc) Qr{E[6
* @see com.adt.dao.UserDAO#getUserCount() @nCd
*/ +csi[c)3E
publicint getUserCount()throws HibernateException { #%h-[/
int count = 0; h3xAJ!
String querySentence = "SELECT count(*) FROM h[@tZ(jrY
9'X7wG
user in class com.adt.po.User"; 3z c U%*
Query query = getSession().createQuery Zo~
@P?~KW6<|
(querySentence); io8'g3<
count = ((Integer)query.iterate().next ] &Rx@&e*
u@cYw:-C
()).intValue(); #*UN >X
return count; $[a8$VY^Cm
} 0a XPPnuX
]Yn_}Bq
/* (non-Javadoc) Y<%@s}zc
* @see com.adt.dao.UserDAO#getUserByPage UWo]s.
pz.JWCU1
(org.flyware.util.page.Page) JAem0jPC8
*/ yL-YzF2
publicList getUserByPage(Page page)throws G\+L~t
y#z
HibernateException { m0a?LY
String querySentence = "FROM user in class (bH`x]h#
gq'Y!BBQy
com.adt.po.User"; #ZrHsfP
Query query = getSession().createQuery ) iN/ua
YOmM=X+'H
(querySentence); 7Bd-!$j+
query.setFirstResult(page.getBeginIndex()) KJaXg;,H
.setMaxResults(page.getEveryPage()); yj.7'{mA
return query.list(); 7E79-r&n
} ~yW4)4k;b
%/zbgS`
} }%{LJ}\Px
i\rDu^VQ
kTu[ y;
7 *`h/
HOJs[mqB%
至此,一个完整的分页程序完成。前台的只需要调用 `3WFjU5a
P"8~$ P#
userManager.listUser(page)即可得到一个Page对象和结果集对象 kr9*,E9cv
%|q>pin2
的综合体,而传入的参数page对象则可以由前台传入,如果用 ]\hSI){
NRIG 1v>
webwork,甚至可以直接在配置文件中指定。 UMm!B `M
biU^[g("
下面给出一个webwork调用示例: -7@/[9Gf`:
java代码: zGkS^Z=(
|8l<$J
@v)p<r^M">
/*Created on 2005-6-17*/ :2rZcoNb.
package com.adt.action.user; 8"8t-E#?
oldA#sA$
import java.util.List; Ki$MpA3j
&-Gqdnc
import org.apache.commons.logging.Log; )I^7)x
import org.apache.commons.logging.LogFactory; SBfT20z[
import org.flyware.util.page.Page; yDegcAn?
Kzm+GW3o[
import com.adt.bo.Result; AicBSqUke
import com.adt.service.UserService; 3yU.& k
import com.opensymphony.xwork.Action; (mTE;s(
~O
oidKT
/** $Y/9SV,
* @author Joa (
+Q&[E"87
*/ g4=pnK8
publicclass ListUser implementsAction{ JP!~,mdS
xy/`ZS2WPq
privatestaticfinal Log logger = LogFactory.getLog "!ug_'VW
[6%VRqY
(ListUser.class); ^cP!\E-^
c4^ks&)'
private UserService userService; g"p%C:NN
4~Vx3gEV:
private Page page; i]YV {
%,}A@H,
privateList users; 8QLj["
pz\
+U7
/* Bn#?zI
* (non-Javadoc) j7$e28|_n
* Oj3.q#)`Z
* @see com.opensymphony.xwork.Action#execute() {GK;63`1
*/ j<VFn~*_
publicString execute()throwsException{ aW)-?(6>
Result result = userService.listUser(page); mD$A4Y-'p
page = result.getPage(); >~[c|ffyo/
users = result.getContent(); -.u]GeMy
return SUCCESS; :t8b39
} @"Fme-~
s%nUaWp~
/** %et }A93
* @return Returns the page. .oYl-.E>&
*/ Sq/
qu-%X
public Page getPage(){ =jOv] /
return page; c[wla<dO*
} aeFe!`F
fk6%XO
/** la0BiLzb]
* @return Returns the users. AN8`7F1
*/ |:nOp(A\*
publicList getUsers(){ lT(WD}OS
return users; Wuc S:8#|
} 7~^GA.92
oTU!R ,
/** B(LWdap~
* @param page S;3R S;
* The page to set. GK)?YM
*/ BP'36?=Zo
publicvoid setPage(Page page){ -3t7*
this.page = page; NO "xL,
} F\JM\{&F
#>b3"[ |
/** R]c+?4J
* @param users I5 o)_nc
* The users to set. TJ_$vI
*/ &=Ar
publicvoid setUsers(List users){ Z&Pg"a?\
this.users = users; bH7X'%r
} :)wy.r;N
Se:.4<
/** n7B7 m,@1
* @param userService $2oTkOA
* The userService to set. "bFTk/
*/ u)X=Qm)
publicvoid setUserService(UserService userService){ r?+%?$
this.userService = userService; >Ea8G,
} ~
-4{B
} #I{h\x><?
PWaw]*dFmy
A -H&
FcR=v0),
nrL9
E'F'
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, /\ y?Y
W98i[Q9A7
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ?i7%x,g(Z
Y>|B;Kj0(
么只需要:
?]|\4]zV
java代码: / ;$#d}R
{C 6=[
CJ/X}hi,
<?xml version="1.0"?> x5,++7Tz
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 9_# >aOqL
7`-Zuf
1.0//EN" "http://www.opensymphony.com/xwork/xwork- J`peX0Stl
%+@O#P
1.0.dtd"> ypbe!Y<i]
q}`${3qQ3
<xwork> nW PF6V>
_GXk0Ia3`
<package name="user" extends="webwork- =e/9&993
-V-RP;">
interceptors"> [.O?Z=5a[V
,~a QL
<!-- The default interceptor stack name [;r)9mh7
1t:Q_j0Ym
--> ;kFDMuuO
<default-interceptor-ref *;l]8.
H7z,j}l
name="myDefaultWebStack"/> )JDs\fUE
9A/\h3HrJ
<action name="listUser" Hbj,[$Jb
l7XUXbYp&=
class="com.adt.action.user.ListUser"> 03|PYk 6EW
<param \l'm[jy>
eV2W{vuI
name="page.everyPage">10</param> #+:9T/*>0
<result %}SGl${-
0ZT5bg_M
name="success">/user/user_list.jsp</result> 8qk?E6
</action> .GsV>H
m;H.#^b*
</package> c&r70L,
j2Cks_$:
</xwork> 8|):`u
> A Khf
)_+rU|We
<>dT64R|
Y'c>:;JEe
|XT)QK1
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 D8inB+/-
ujDd1Bxf?
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 C\S3Gs
_K`wG}YIE
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 $*SW8'],`
AJf4_+He
00G%gQXk,
Vr )<\h
b=g8eMm
我写的一个用于分页的类,用了泛型了,hoho GQ t8p[!
gD,1 06%
java代码: O-ew%@_
H2&@shOOQJ
N^#ZJoR
package com.intokr.util; M}`B{]lLz
98j>1"8
import java.util.List; Ov};e
Z,RzN5eN
/** O,J>/
* 用于分页的类<br> VeGL)
* 可以用于传递查询的结果也可以用于传送查询的参数<br> aDq5C-MzG
* y[`l3;u:'
* @version 0.01 J5di[nu
* @author cheng yyoqX"v[
*/ nc~F_i=
public class Paginator<E> { s:OFVlC%\
privateint count = 0; // 总记录数 o}$XH,-9&
privateint p = 1; // 页编号 aK&b{d
privateint num = 20; // 每页的记录数 W,4QzcQR
privateList<E> results = null; // 结果 '= _/ 1F*q
NiWa7 /Hr
/** NMW#AZVd
* 结果总数 kjW+QT?T&
*/ ZO!I.
publicint getCount(){ Qt iDTr
return count; &%8'8,.
} R%Qf7Q
:H7D~ n
publicvoid setCount(int count){ ZW-yP2
this.count = count; ]=.\-K
} ?i)f^O
l,R/Gl
/** 0)%YNaskj
* 本结果所在的页码,从1开始 P<PJ)>
* $$D}I*^Dt
* @return Returns the pageNo. E4gYemuN
*/
*-+&[P]m
publicint getP(){ R?,an2
return p; ~J5+i9T.)
} 1q~+E\x
0]>u)%
/** 03xa'Of>
* if(p<=0) p=1 O?NeSx1
* S\''e`Eb"5
* @param p Ot:CPm@
*/ Vx(B{5>Vu
publicvoid setP(int p){ kQ4dwF~
if(p <= 0) I[=j&rK`
p = 1; l/BLUl~z
this.p = p; Jpj}@,
} 3 ,>0a
pwO>h>ik
/** * 1T&
* 每页记录数量 \X<bH&x:z
*/ `Y
BC
publicint getNum(){ INcg S MM
return num; X-
pqw~$
} @xQgY*f#
*n;!G8\
/** AcS|c:3MUy
* if(num<1) num=1 p%iGc<vHX
*/ 3Dg,GaRk
publicvoid setNum(int num){ WzAb|&?
if(num < 1) x N=i]~
num = 1; ]Gpxhg
this.num = num; Yb:\a/ y
} H70LhN
8j Mk)-
/** H]Cy=Zi"
* 获得总页数 P6E3-?4j
*/ &/mA7Vf>eR
publicint getPageNum(){ nS/)P4z
return(count - 1) / num + 1; d1T,eJ}
} B,M(@5wz
UV5Ie!\nm
/** 1lq(PGX)
* 获得本页的开始编号,为 (p-1)*num+1 j H19k}D
*/ Acnl^x7Y1
publicint getStart(){ e.]K L('
return(p - 1) * num + 1; aF)1Nm[
} GRGzP&}@
^sa#8^,K
/** nFE4qm
* @return Returns the results. =3|O%\
*/ W^fuScG)c
publicList<E> getResults(){ F\fWvXdW
return results; 4/mig0"N.
} 2}YOcnB
aJYgzr,
public void setResults(List<E> results){ z)'M k[
this.results = results; "vXxv'0\f
} Tg!i%v(-t
xG}(5Tt
public String toString(){ !O-T0O
StringBuilder buff = new StringBuilder I'PeN0T
f
F_Z- 8>P
(); N U|d
buff.append("{"); , 3,gG"
buff.append("count:").append(count); .^N/peUq
buff.append(",p:").append(p); #6ri-n
buff.append(",nump:").append(num); Uh7v@YMC
buff.append(",results:").append =.y~f A!
D<|qaHB=
(results); MG[o%I96
buff.append("}"); N e#WI'
return buff.toString(); $P>`m$(8
} ${+ @gJ+S
7#@cz5Su
} S?RN?1
cj+ FRG~u
j]*j}%hz