Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [xGwqa03
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 e,Cc.T\o
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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 u'? +JUd1
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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 KS#A*BRQ
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分页支持类: cQ1[x>OcU
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java代码: <5L99<E
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package com.javaeye.common.util; >4@w|7lS
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import java.util.List; a;5clonB
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publicclass PaginationSupport { 0;x&\x7K
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publicfinalstaticint PAGESIZE = 30; .+(ED
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privateint pageSize = PAGESIZE; OM.-apzC
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privateList items; ~5Fx[q
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privateint totalCount; 'g<"@SS+
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privateint[] indexes = newint[0]; }bihlyB&Q
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privateint startIndex = 0; 'WHI.*=
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public PaginationSupport(List items, int nt"\FZ*;3
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totalCount){ !hJ!ck]M
setPageSize(PAGESIZE); 7/M[T\c
setTotalCount(totalCount); ;a|%W4 "
setItems(items); 0++RxYFCL
setStartIndex(0); &@xm< A\S
} ?Xpk"N7
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public PaginationSupport(List items, int U;kNo3=
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totalCount, int startIndex){ aAqM)T83
setPageSize(PAGESIZE); }#tbK 2[
setTotalCount(totalCount); gs+nJ+b
setItems(items); H|e7IsY%
setStartIndex(startIndex); S*n5d >;
} A1;'S<a
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public PaginationSupport(List items, int TP| ogF?
}@.@k6`n
totalCount, int pageSize, int startIndex){ @r<2]RXlc
setPageSize(pageSize); KtJc9dnX
setTotalCount(totalCount); jHob{3
setItems(items); CqWO 0
setStartIndex(startIndex); `_.:O,^n^
} y%9Hu
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publicList getItems(){ ;>/Mal
return items; mS}.?[d"
} > {d9z9O
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publicvoid setItems(List items){ ;TC]<N.YJT
this.items = items; [ Y{
} hVyeHbx
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publicint getPageSize(){ hKhad8
return pageSize; ajG_t
} ;dfIzi
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publicvoid setPageSize(int pageSize){ e34g=]"
this.pageSize = pageSize; K}N~KDW R|
} d" 0&=/
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publicint getTotalCount(){ -`\n/"#X6i
return totalCount; Wm}T=L`
} 9]T61Z{OW1
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publicvoid setTotalCount(int totalCount){ ci+ajON
if(totalCount > 0){ >`[+24e
this.totalCount = totalCount; &*8.%qe;
int count = totalCount / $mf O:%
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pageSize; x8c>2w;6x^
if(totalCount % pageSize > 0) PYNY1|3
count++; vo:h"ti
indexes = newint[count]; YnU*MC}
for(int i = 0; i < count; i++){ *T}c{/
indexes = pageSize * 6)ysiAH?
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i; H}&JrT95
} Mcz;`h|EW
}else{ wmX(%5vY^
this.totalCount = 0; ,jW a&7
} I\-M`^@
} DTsD<o
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publicint[] getIndexes(){ Z6-
return indexes; 9:3`LY3wW
} ew,okRCN
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publicvoid setIndexes(int[] indexes){ cM,g,E}
this.indexes = indexes; x1Z'_Qw
} 7$Wbf4
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publicint getStartIndex(){ .qf~t/o
return startIndex; 4\ElMb[]
} Z:<wB#G
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publicvoid setStartIndex(int startIndex){ Z<=L
if(totalCount <= 0) ugj I$u
this.startIndex = 0; 2[1t
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elseif(startIndex >= totalCount) F.@|-wq&
this.startIndex = indexes p1.3)=T
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[indexes.length - 1]; +~:OUR*>
elseif(startIndex < 0) b&Laxki
this.startIndex = 0; 2dB]Lw@s
else{ -2u)orWP
this.startIndex = indexes h3GUFiZ.
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[startIndex / pageSize]; e]dFNunFq0
} b?!S$S xz
} xh#pw2v7V
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publicint getNextIndex(){ p)z#%BY56
int nextIndex = getStartIndex() + oLq N
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pageSize; lu+KfKa
if(nextIndex >= totalCount) j
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return getStartIndex(); I#]pk!
else 6f
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return nextIndex; ;bHS^
} QX&Y6CC`]
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publicint getPreviousIndex(){ :AQ9-&i/a-
int previousIndex = getStartIndex() - 3 _!MVT
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pageSize; n{{"+;oR
if(previousIndex < 0) o9C#5%9
return0; +M#}(hK
else O:~J_Wwl!
return previousIndex; MXDCOe~07
} !I&,!$
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} %<p/s;eu
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抽象业务类 M0?%r`
java代码: d.Ccc/1-
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/** s +qodb+
* Created on 2005-7-12 0r i
*/ !) `*e>]x
package com.javaeye.common.business; yc`3)
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import java.io.Serializable; ox\D04:M
import java.util.List; o=Mm=;H
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import org.hibernate.Criteria; *XYp~b
import org.hibernate.HibernateException; Z( "-7_
import org.hibernate.Session; w8:
import org.hibernate.criterion.DetachedCriteria; 5:5d=7WX
import org.hibernate.criterion.Projections; ^
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import Aeo=m}C;
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org.springframework.orm.hibernate3.HibernateCallback; '{.8tT?tJ
import M^hz<<:$
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org.springframework.orm.hibernate3.support.HibernateDaoS m],.w M8
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upport; -II03 S1
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import com.javaeye.common.util.PaginationSupport; q"S,<I<f
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public abstract class AbstractManager extends PY3bn).uR
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HibernateDaoSupport { 3J/l>1[
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privateboolean cacheQueries = false; cW"DDm
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privateString queryCacheRegion; bC) <K/Q9
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publicvoid setCacheQueries(boolean |;d#k+/;
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cacheQueries){ CBpwtI>p
this.cacheQueries = cacheQueries; iE_[]Vgc
} ma<uXq
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publicvoid setQueryCacheRegion(String c6h+8QS
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queryCacheRegion){ ]$sb<o
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this.queryCacheRegion = rKT.~ZP\
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queryCacheRegion; _% \%
} 7xux%:BN
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publicvoid save(finalObject entity){ /EegP@[
getHibernateTemplate().save(entity); c9c3o{(6Y
} )~ &gBX
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publicvoid persist(finalObject entity){ o61rTj
getHibernateTemplate().save(entity); fgC@(dvfk
} D/;[x{;E
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publicvoid update(finalObject entity){ G-R83Orl
getHibernateTemplate().update(entity); Ai^0{kF6
} JL{fW>5y|
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publicvoid delete(finalObject entity){ WiQVZ{
getHibernateTemplate().delete(entity); o1*P|.`
} Aho*E9VW
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publicObject load(finalClass entity, L<B)BEE.
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finalSerializable id){ W2zG"Q
return getHibernateTemplate().load ,`k6@4
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(entity, id); =K|#5p`
} X%N!gy
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publicObject get(finalClass entity, s1#A0%gx
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finalSerializable id){ ![fNlG!r
return getHibernateTemplate().get #Ak|p#7 ^
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(entity, id); ' u;Zw%O(J
} @3=q9ftm
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publicList findAll(finalClass entity){ Iu5 9W>
return getHibernateTemplate().find("from ~3Zz.!F
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" + entity.getName()); y65lbl%Zn
} h+&iWb3;
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publicList findByNamedQuery(finalString ^e;9_(
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namedQuery){ HvKdV`bz
return getHibernateTemplate .n4{xQo,EJ
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().findByNamedQuery(namedQuery); ?~.:C'
} cR,'aX
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publicList findByNamedQuery(finalString query, l]Xbd{
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finalObject parameter){ D]rYg'
return getHibernateTemplate bAN>\zG+
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().findByNamedQuery(query, parameter); k'PvQl"I
} }m%&|:PH
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publicList findByNamedQuery(finalString query, F< 5kcu#iL
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finalObject[] parameters){ .XRe:\8mc
return getHibernateTemplate i_l{#*t
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().findByNamedQuery(query, parameters); 9ZatlI,
} J4U_utp
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publicList find(finalString query){ LHu
return getHibernateTemplate().find +Wy `X5v
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(query); ],~[ ^0
} 8faT@J'e;
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publicList find(finalString query, finalObject "L1LL
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parameter){ 55UPd#E'
return getHibernateTemplate().find K :+q9;g
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(query, parameter); >9i>A:
} 5[r}'08b
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public PaginationSupport findPageByCriteria &)JoB
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(final DetachedCriteria detachedCriteria){ ?EPHq,
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return findPageByCriteria m\/) m]wR
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); yV(9@lj3;
} -"a(<JC^NI
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public PaginationSupport findPageByCriteria xfC$u`e=
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(final DetachedCriteria detachedCriteria, finalint L;L_$hu)
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startIndex){ 2EN}"Du]mj
return findPageByCriteria Ui9;rh$1eU
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(detachedCriteria, PaginationSupport.PAGESIZE, ,{msJyacmR
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startIndex); ,`!lZ|
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} P$N5j~*
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public PaginationSupport findPageByCriteria M"{*))O\-c
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(final DetachedCriteria detachedCriteria, finalint ;mz#$"(
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pageSize, #f_'&m
finalint startIndex){ h6<i,1gQ1
return(PaginationSupport) '@w'(}3!3R
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getHibernateTemplate().execute(new HibernateCallback(){ 2J$vX(
publicObject doInHibernate BhbfPQ
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(Session session)throws HibernateException { w^ofH-R/
Criteria criteria = uTPAf^|
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detachedCriteria.getExecutableCriteria(session); nnE'zk<"
int totalCount = V=5*)i/
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((Integer) criteria.setProjection(Projections.rowCount I8B0@ZtV
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()).uniqueResult()).intValue();
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criteria.setProjection 5 $$Cav
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(null); ].aFdy
List items = AcH!KbYf
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criteria.setFirstResult(startIndex).setMaxResults uV@'898%5
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(pageSize).list(); M6qNh`+HO
PaginationSupport ps = G,^ ?qbHg
m^m=/'<+
new PaginationSupport(items, totalCount, pageSize, @p^EXc*|
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startIndex); k{b|w')
return ps; u ysTyzx
} `'3 De(
}, true); ,)J>8eV
} (18ZEKk
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}
public List findAllByCriteria(final fO^s4gWTg
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DetachedCriteria detachedCriteria){ YDYNAOThnb
return(List) getHibernateTemplate HrFbUK@@
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().execute(new HibernateCallback(){ XkoPN]0n
publicObject doInHibernate @(E6P;+{
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(Session session)throws HibernateException { KHC Fz
Criteria criteria = '73}{" '
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detachedCriteria.getExecutableCriteria(session); 0:4>rYBC
return criteria.list(); $^czqA-&
} ][V`ym-e
}, true); D8PC;@m
} )1@%!fr
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public int getCountByCriteria(final B^zg#x#8
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DetachedCriteria detachedCriteria){ -O=xgvh"
Integer count = (Integer) P0OMu/
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getHibernateTemplate().execute(new HibernateCallback(){ ;qbK[3.
publicObject doInHibernate (.YSs
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(Session session)throws HibernateException { }0@@_Y]CC
Criteria criteria = QLHEzEvf{/
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detachedCriteria.getExecutableCriteria(session); P0hr=/h4
return *kTp(*K/7`
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criteria.setProjection(Projections.rowCount 8Exky^OT|
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()).uniqueResult(); EK0~3HSZ
} 60A!Gob
}, true); 4t/ ?b
return count.intValue(); ev+H{5W8
} h?B1Emlq
} !?+0O]`}
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用户在web层构造查询条件detachedCriteria,和可选的 %0}}Qt
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 L;{{P7
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PaginationSupport的实例ps。 [cznhIvyO
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ps.getItems()得到已分页好的结果集 @o'L! 5Y
ps.getIndexes()得到分页索引的数组 83'+q((<
ps.getTotalCount()得到总结果数 {+d)M
ps.getStartIndex()当前分页索引 ~[og\QZX
ps.getNextIndex()下一页索引 g`C8ouy
ps.getPreviousIndex()上一页索引 W_ Hoa*~
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 i^A=nsD`
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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 W$;qhB
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一下代码重构了。 hmG8
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我把原本我的做法也提供出来供大家讨论吧: h# Z,ud_
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首先,为了实现分页查询,我封装了一个Page类: Q{'4,J-w
java代码: M3F1O6=4j
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/*Created on 2005-4-14*/ W ;+()vC
package org.flyware.util.page; Y}t)!}p$r
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/** _FcTY5."S
* @author Joa JEWc{)4QD
* xaoR\H
*/ (&r`
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publicclass Page { [UC_
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/** imply if the page has previous page */ En\q. 3
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privateboolean hasPrePage; s3Zt)xQ3
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/** imply if the page has next page */ xVX:kDX
privateboolean hasNextPage; 7I&o
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/** the number of every page */ IO=$+c
privateint everyPage; $_TS]~y4}
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/** the total page number */ =2QP7W3mg<
privateint totalPage; :&'jh/vRN
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/** the number of current page */ r7R.dD/.
privateint currentPage; =_m3~=Z
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/** the begin index of the records by the current mv~?1aIKD
zb"4_L@m2
query */ PeqW+Q.
privateint beginIndex; 3tJfh=r=1
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/** The default constructor */ ZnzO]
public Page(){ FkuD Gg~a
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} [{GN#W|AGP
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/** construct the page by everyPage GRkN0|ovfj
* @param everyPage |>'N^
* */ Meep
public Page(int everyPage){ *l"CIG'
this.everyPage = everyPage; zn&ZXFgN
} ePJ_O~c
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/** The whole constructor */ Jp}\@T.
public Page(boolean hasPrePage, boolean hasNextPage, Ok{1{EmP
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int everyPage, int totalPage, ~OR^
int currentPage, int beginIndex){ A?}[rM
Z
this.hasPrePage = hasPrePage; P:vp/x!
this.hasNextPage = hasNextPage; `aG_ m/7|
this.everyPage = everyPage; U$+,|\9
this.totalPage = totalPage; ;s3\Z^h4kd
this.currentPage = currentPage; eiyr^Sch.
this.beginIndex = beginIndex; GI,TE
} WG\
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/** 2@
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* @return G/(,,T}eG
* Returns the beginIndex. %D:VcY9OC
*/ o 7tUv"Rs
publicint getBeginIndex(){ <rK[ &JlJ
return beginIndex; 4'*.3f'bp
} _xm<zy{`S
}d>.Nj#zh
/** QKq4kAaJ!
* @param beginIndex |%ZJN{!R
* The beginIndex to set. :3D6OBkB
*/ YG:^gi
publicvoid setBeginIndex(int beginIndex){ (Sgsy^|N
this.beginIndex = beginIndex; tD}-&"REP
} 6B7*|R>
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/** Ert={"Q
* @return !uIY ,
* Returns the currentPage. vWM&4|Q1~
*/ 0,0Z!-Y
publicint getCurrentPage(){ 'Q :%s
return currentPage; uYg Q?*Z
} 4
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Fbd
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/** qpCaW0]7
* @param currentPage EsX(<bx
* The currentPage to set. \#) YS
*/ =p=/@ FN
publicvoid setCurrentPage(int currentPage){ rXMc0SPk
this.currentPage = currentPage; z\ONwMl
} |nnFjGC`~
VV}"zc^
/** 'Rsr*gX#
* @return _D?/$D7u#%
* Returns the everyPage. X`WS&!C<
*/ Jj=N+,km
publicint getEveryPage(){ U/s
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return everyPage; h4 9q(085V
} eWex/ m
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/** x4wTQ$*1
* @param everyPage wEX<[#a-
* The everyPage to set. o
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*/ d-e/0F!
publicvoid setEveryPage(int everyPage){ G!I5Er0pdy
this.everyPage = everyPage; WoGnJ0N q
} G/},lUzLg
I(7iD. ^:
/** ]S@T|08b
* @return Vjt7X"_/
* Returns the hasNextPage. Kg>B$fBx)
*/ YlG#sBzl
publicboolean getHasNextPage(){ L xIKH
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return hasNextPage; 9e>2kd
} 3gVU#T[[
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/** cl&?'`
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* @param hasNextPage ~uZ9%UB_m
* The hasNextPage to set. G;u~H<
*/ W% Lrp{
publicvoid setHasNextPage(boolean hasNextPage){ ~Y*.cGA
this.hasNextPage = hasNextPage; c7@/<*E+
} kv2o.q
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/** LK*9`dzv=G
* @return W?E,"z
* Returns the hasPrePage. g4Dck4^!4
*/ 2W_[|.;'
publicboolean getHasPrePage(){ BCz4
s{F
return hasPrePage; er1XZ
} JLo E)\Mi
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/** L&:A59)1k
* @param hasPrePage Vraz}JV
* The hasPrePage to set. DO*6gzW
*/ ^/%Y]d$
publicvoid setHasPrePage(boolean hasPrePage){ W|rAn2H
this.hasPrePage = hasPrePage; *dBmb
} P{`fav
l$c/!V[3
/** V/"RCqY4
* @return Returns the totalPage. ;Wk3>\nT-
* 6]<yR>
'
*/ H\<0{#F
publicint getTotalPage(){ C\BKdx5;
return totalPage; yY49JZ
} h;r^9g
G,Eh8HboK
/** &Fuk+Cu{
* @param totalPage Zj ` ;IYFG
* The totalPage to set.
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*/ OiZ-y7;k^
publicvoid setTotalPage(int totalPage){ '@#(jY0_
this.totalPage = totalPage; V3VTbgF
} |r;>2b/ x
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} >Jn` RsuV
lnjs{`^
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UCj+V@{
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 tCR~z1
m3P7*S5NJ7
个PageUtil,负责对Page对象进行构造: ^*$!9~
java代码: IV':sNV
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/*Created on 2005-4-14*/ f]?&R c2C
package org.flyware.util.page; 06.8m;{N
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import org.apache.commons.logging.Log; z%+rI
import org.apache.commons.logging.LogFactory; [U^Cz{G
zlQBBm;fE
/** "o u{bKe
* @author Joa i-4L{T\K
* 2MYez>D
*/ lAC"7 Z?F
publicclass PageUtil {
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T7/DH
privatestaticfinal Log logger = LogFactory.getLog $;=?[Cn
?^7X2 u$nm
(PageUtil.class); $w-@Oa*h9U
~/aCzx~
/** j)iUg03>/4
* Use the origin page to create a new page \/Q~C!
* @param page X#h a*u~U
* @param totalRecords v6uRzFw
* @return 0ZI}eZA j
*/ y>u|3:z
publicstatic Page createPage(Page page, int ,`a8@
Em{;l:;(W
totalRecords){ W}zq9|p
return createPage(page.getEveryPage(), 3?_%|;ga
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page.getCurrentPage(), totalRecords); ;KmrBNF
} (0_zp`)
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/** x*TJYST
* the basic page utils not including exception k_?OEkgUh
| lzcyz
handler a[}?!G-Wt|
* @param everyPage +`B^D
* @param currentPage En&gI`3n
* @param totalRecords eBmHb\
* @return page RK$(
*/ pTTM(Hrx
publicstatic Page createPage(int everyPage, int c3PA<q[
y[S9b(:+
currentPage, int totalRecords){ q?]KZ_a
everyPage = getEveryPage(everyPage); ==%5Ci7qMy
currentPage = getCurrentPage(currentPage); e8(Qx3T?b
int beginIndex = getBeginIndex(everyPage, 8o
$` '
6jm/y@|F!
currentPage); u%"5<ll
int totalPage = getTotalPage(everyPage, ;Kg7}4`I
-w)v38iX!
totalRecords); /f+BeQ3#/
boolean hasNextPage = hasNextPage(currentPage, hPgYKa8u
pSYEC,0B
totalPage); ?pd/cj^
boolean hasPrePage = hasPrePage(currentPage); #RSUChe7w
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returnnew Page(hasPrePage, hasNextPage, Hm|N{
everyPage, totalPage, P39oHW
currentPage, ~P~q'
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beginIndex); S-7 C'dc
} pbWjTI $
jt* B0'Sa
privatestaticint getEveryPage(int everyPage){ q3K}2g
return everyPage == 0 ? 10 : everyPage; mC(YO y
} ]\}MSo3
T;PLUjp}
privatestaticint getCurrentPage(int currentPage){ -'*<;]P+.
return currentPage == 0 ? 1 : currentPage; 01RW|rN
} H}CmSo8&
q68m*1?y
privatestaticint getBeginIndex(int everyPage, int 7<B-2g
^1_[UG
currentPage){ AqaMi
return(currentPage - 1) * everyPage; ~>~qA0m"m
} f3>DmH#
n3-VqYUP
privatestaticint getTotalPage(int everyPage, int Y5"HKW^
2hryY
totalRecords){ 7+X~i@#rU
int totalPage = 0; |}<Gz+E>
AKk&
if(totalRecords % everyPage == 0) HN5,MD[
totalPage = totalRecords / everyPage; qFq$a9w|@
else WoNY8
8hT
totalPage = totalRecords / everyPage + 1 ; 2vsV:LS.
/?z3*x
return totalPage; 9 v8^uPA
} #<u;.'R
Ra
H1aS(
privatestaticboolean hasPrePage(int currentPage){ :l iDoGDi
return currentPage == 1 ? false : true; &rX#A@=
} /J&DYxl":
[9MbNJt 8~
privatestaticboolean hasNextPage(int currentPage, 3Z#WAhfS:
?*7Mn`
int totalPage){ -g|ji.
return currentPage == totalPage || totalPage == WA:r4V
fd>&RbUp
0 ? false : true; DrxQ(yo}
} Q#K10*-O6
@A*>lUo
'4Qsl~[Eh
} 8B(v6(h
Z`ww[Tbv~
k{UeY[,jb
j},i=v
l5KO_"hy
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。 27$,D XD
L<Z,@q`
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 Xw7'I
* >8EMq\^
做法如下: I:UDEoQo
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 iXvrZofE
(vchZn#
的信息,和一个结果集List: +"k?G
java代码: ?~yJ7~3TS<
5wl;fL~e
#5'&
|<
/*Created on 2005-6-13*/ ``6-
package com.adt.bo; Nv6"c<(L=
wArfnB&
import java.util.List; 6f
?,v5
.sFN[>)
import org.flyware.util.page.Page; IvI..#EzG
4fjwC,,
/** X:g#&e_
* @author Joa 'V&Uh]>
*/ x',6VTz^
publicclass Result { r`h".=oD
~<s^HP2U{
private Page page; 4i+%~X@p
N>]J$[j
private List content; #Q*V9kvU/H
#h4FLF_w
/** ]6A wd A
* The default constructor ZKpJc'h
*/ 9
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public Result(){ ZrZDyXL
super(); K4YD}[
} 7v0AG:
=oI6yf&8 Z
/** )4c?BCgy
* The constructor using fields R:R<Xt N`5
* CgYX^h?Y9
* @param page WW&Wh<4
* @param content mdEl
CC0
*/ i*@PywT"i3
public Result(Page page, List content){ G43r85LO
this.page = page; {P_7AM
this.content = content; Fkq^2o
]
} _nxH;Za
T&b_*)=S
/** FoH1O+e
* @return Returns the content. c-n/E. E
*/ b(Tvc
publicList getContent(){ (j??
return content; +8itP>
} FU>KiBV#
#Nco|v
/** C"_ Roir?
* @return Returns the page. h0g?=hJq
*/ /S1/ ZI
public Page getPage(){ Qx8(w"k*
return page; CS(2bj^6D
} p:W]
.jk
A'i@
/** ;+6><O!G
* @param content &);P|v`8
* The content to set. kV4Oq.E
*/ 3JBXGT0gJ
public void setContent(List content){
6ST(=X_C
this.content = content; nhjT2Sl
} C])s'XTs
N)R5#JX
/** *L$_80
* @param page " r o'?
* The page to set. 1
ptyiy
*/ [0]A-#J
publicvoid setPage(Page page){ ZILJXX4
this.page = page; v:yU+s|kN
} y1Z>{SDiq
} [w|Klq5
]W`?0VwF
,$>l[G;Bm
X:;x5'|
'@Rk#=85Z
2. 编写业务逻辑接口,并实现它(UserManager, &r4|WM/ec
s*<T'0&w0S
UserManagerImpl) ::$W
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java代码: Y_!+Y<x7v
Y68A+
B.
qIsf!1I?
/*Created on 2005-7-15*/ dpylJ2
package com.adt.service; 18QqZ,t
uW=G1 *n-
import net.sf.hibernate.HibernateException; #5z0~Mg-X
GJrmK
import org.flyware.util.page.Page; L+<h5>6
`?3f76}h
import com.adt.bo.Result; ThI}~$Y
9 i/
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/** $8%"bR;Hu
* @author Joa Y<irNp9
*/ f pq|mY
publicinterface UserManager { 6uFw+Ya#
-bHlFNRm
public Result listUser(Page page)throws /(51\RYkir
'hs4k|B
HibernateException; /:(A9b-B
t(uvc{K*
} }^&f {
Y_+#|]=$B
'o#oRK{#
QRf>lZP
$6pLsX
java代码: yxp,)os:
Hxgc9Fis
Q+9:]Bt
/*Created on 2005-7-15*/ |.0~'
package com.adt.service.impl; !W@mW
5J|
;..z)OP_
import java.util.List; b(;u2 8
`Y4K w
import net.sf.hibernate.HibernateException; n-" (~
ka\{?:r,8
import org.flyware.util.page.Page; 0
h!Du|?
import org.flyware.util.page.PageUtil; L#byYB;E{
T[k$ [
import com.adt.bo.Result; |y eQz
import com.adt.dao.UserDAO; f?)7MR=
import com.adt.exception.ObjectNotFoundException; <;PKec
import com.adt.service.UserManager; J*$%d1
$$1t4=Pz
/** Zdqm|_R[
* @author Joa |;wc8;
*/ aPEI_P+Ls
publicclass UserManagerImpl implements UserManager { )c' 45bD
\\KjiT'
private UserDAO userDAO; ^?+[yvq
P{6$".kIY
/** Rq5'=L
* @param userDAO The userDAO to set. '!7>*<
*/ '%[ Y
publicvoid setUserDAO(UserDAO userDAO){ goIvm:?
this.userDAO = userDAO; ~. vridH
} {&IB[Y6
;98b SR/
/* (non-Javadoc) o&E8<e
* @see com.adt.service.UserManager#listUser eb\S pdM6
aM;SE9/U
(org.flyware.util.page.Page) Y_:jc{?
*/ b3E1S+\=~
public Result listUser(Page page)throws S=!WFKcJR
<7\j\`
HibernateException, ObjectNotFoundException { i3N{Dt
int totalRecords = userDAO.getUserCount(); (is' ,4^b
if(totalRecords == 0) $ItmYj.m
throw new ObjectNotFoundException D0FX"BY7
m.m6.
("userNotExist"); :&vX0
Ce:
page = PageUtil.createPage(page, totalRecords); ?IHt T3'Rt
List users = userDAO.getUserByPage(page); uv/\1N;V3
returnnew Result(page, users); FDLo|aP/v
} 6-_g1vq
zY_J7,0g
} [q2:d^_FA
JfN
'11,$
y%i9 b&gDd
d/Q#Z
F~
5,-atDM
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 vu*e*b$}
2lpPN[~d
询,接下来编写UserDAO的代码: ))|d~m
3. UserDAO 和 UserDAOImpl: /GO-
java代码: F%|P#CaB
W-s 6+DY
T(?w}i
/*Created on 2005-7-15*/ 0NU%z.(%s
package com.adt.dao; HfVHjF)
M=liG+d
import java.util.List; K'Ywv@
2j%=o?me^p
import org.flyware.util.page.Page; ?K[Y"*y2
ay7\Ae]
import net.sf.hibernate.HibernateException;
)Ri!
z1Ieva]
/** zK5&,/
* @author Joa ,6;n[p"h|r
*/ 6U*CR=4
publicinterface UserDAO extends BaseDAO { 6^LXctW.
zX_F+"]THt
publicList getUserByName(String name)throws O3o^%0
Xs052c|s
HibernateException; metn&
mxgT}L0i
publicint getUserCount()throws HibernateException; t8-Nli*O
uAA2G\3
publicList getUserByPage(Page page)throws b_~XTWP$l
F;ttqL
HibernateException; x*vD^1"'P
~ps,U
} 'r]6 GC8Z$
Z8$BgP
(uvQ/!
P!+Gwm{
z;1dMQ,#
java代码: ]!{S2x&"
]M*`Y[5"
aG
}oI!
/*Created on 2005-7-15*/ /(JG\Ut
package com.adt.dao.impl; e&z@yy$
0! 3. .5==
import java.util.List; T&'Jc
?A|JKOst]
import org.flyware.util.page.Page; m~
ah!QM
bHG<B
import net.sf.hibernate.HibernateException; v-z%3x.f
import net.sf.hibernate.Query; Ih:Q}V#6
+;~o R_p
import com.adt.dao.UserDAO; i`gM> q&
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/** VEh9N
* @author Joa lwf4ke
*/ / rc[HbNg.
public class UserDAOImpl extends BaseDAOHibernateImpl vWoppt
!ddyJJ^a
implements UserDAO { Q[#}Oh6$
N4ZV+
|
/* (non-Javadoc) `Jc/ o=]
* @see com.adt.dao.UserDAO#getUserByName ?2&= +QaT
lZ-U/$od
(java.lang.String) S3Y.+. 0U
*/ ,N(Yjq"R
publicList getUserByName(String name)throws nnj<k5
<8b1OdA
HibernateException { (U&
String querySentence = "FROM user in class b~vV++ou_
Jo\MDyb]
com.adt.po.User WHERE user.name=:name"; Z|E9}Il]
Query query = getSession().createQuery o+Jnn"8
\+V"JIStUj
(querySentence); nv_v FK
query.setParameter("name", name); !4a fU:
return query.list(); v]( Y n)#
} eI$V2
<9,h!
/* (non-Javadoc) MG vz-E1e
* @see com.adt.dao.UserDAO#getUserCount() )7*'r@
*/ cK1^jH<|
publicint getUserCount()throws HibernateException { $~6MR_Yq
int count = 0; J|
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String querySentence = "SELECT count(*) FROM <{cY2cx~3
6
^3RfF^W
user in class com.adt.po.User"; xw9ZRu<z
Query query = getSession().createQuery F~6]II
,5$G0
(querySentence); Fy{yg]O"
count = ((Integer)query.iterate().next ;<garDf
R278 ^E
()).intValue(); N-upNuv
return count; 1M&Lb.J6
} >Y08/OAI.2
YAc:QVT87
/* (non-Javadoc) Sh!c]r>\Q
* @see com.adt.dao.UserDAO#getUserByPage L4Jm8sy{
l48$8Mgrr
(org.flyware.util.page.Page) 'UsR/h5T
*/ `TJhH<z"%
publicList getUserByPage(Page page)throws @6G)(NGD
;"nO'wN:h
HibernateException { xJ$uoy3+
String querySentence = "FROM user in class zTcz+3x
veq3t$sj
com.adt.po.User"; A8&@Vxdz
Query query = getSession().createQuery ! :]_-DX
#$BFTlm|
(querySentence); }eVDe(7_
query.setFirstResult(page.getBeginIndex()) 72Bc0Wg
.setMaxResults(page.getEveryPage()); et+lL"&
return query.list(); B9NUafK=
} VF2,(f-*
IRQtA
Z V$
} ]!AS%D`
FXBmatBck
~k&b
I4N7wnBp
zU!{_Ao9
至此,一个完整的分页程序完成。前台的只需要调用 <=n;5hv:
bpBn3f`?*
userManager.listUser(page)即可得到一个Page对象和结果集对象 Z (6.e8fK
tAN!LI+w
的综合体,而传入的参数page对象则可以由前台传入,如果用 oUnb-,8n
9$$ Ijf
webwork,甚至可以直接在配置文件中指定。 F)cCaE;
4nm.ea|
下面给出一个webwork调用示例: 5.5kH$;>
java代码: SEI0G_wk$
+
-Rf@
6HCg<_j]
/*Created on 2005-6-17*/ q#3T
L<
package com.adt.action.user; %J1'>nI!q
# QwX|x{
import java.util.List; 6c]4(%8
@;eH~3P
import org.apache.commons.logging.Log; 6 EqN>.
import org.apache.commons.logging.LogFactory; 3yRvs;nWS
import org.flyware.util.page.Page; B7uK:J:c*H
]z'L1vQl7
import com.adt.bo.Result; :Ob4WU
import com.adt.service.UserService; o?}dHTk7
import com.opensymphony.xwork.Action; t,%m-dU
k4$zM/ob
/** q+9^rQ
* @author Joa 8)8~c@
*/ y0p=E^QM
publicclass ListUser implementsAction{ fC'u-m?!Q'
sX6\AYF1M
privatestaticfinal Log logger = LogFactory.getLog N-2#-poDe
'df@4} 9
(ListUser.class); @\F7nhSfa
E}4{{{r
private UserService userService; 9mHCms
/UunWZ u%
private Page page; &C
MBTY#u
qWW\d', .
privateList users; K{_~W yRF
liYsUmjZ=
/* Vw w 211
* (non-Javadoc) Kq")|9=d
* sP^:*B0
* @see com.opensymphony.xwork.Action#execute()
Jy:*GW6
*/ %6(\Ki6I
publicString execute()throwsException{ =k<b* 8
Result result = userService.listUser(page); K7C
<}y
page = result.getPage(); k+{~#@
users = result.getContent(); -I{op
wd
return SUCCESS; JYNnzgd
} #tZ!D^GQHq
6%p6BK6
/** =T3{!\tH
* @return Returns the page. (QIU 3EN
*/ 4OM
]8I!
public Page getPage(){ 10zM8<bl
return page; x3Cn:F
} 8*8Y\"
[cDDZ+6
/** i +@avoW
* @return Returns the users. 4}D&=0IZ
*/ w;@v#<q6
publicList getUsers(){ by9UwM=gp
return users; J37vA zK%
} pm+E)z6Yo
/
P@P1l|I
/** Uot(3p!S6
* @param page \68bXY.
* The page to set. _lI(!tj(
*/ 8Q/cJ+&
publicvoid setPage(Page page){ 4?@5JpC9VA
this.page = page; $o+@}B0)
} *8qRdI9
a?Fz&BE
/** 1y[~xxgE
* @param users R|Bi%q|4P
* The users to set. t@lTA>;U@
*/ "
AvEo
publicvoid setUsers(List users){ i8Be%y%y
this.users = users; A*qR<cp[
} `vt+VUNf
YH^U"\}i
/** ^Mm%`B7W
* @param userService _Rjbm'kC
* The userService to set. xM)P=y_!M+
*/ @&HLm^j2O
publicvoid setUserService(UserService userService){ zfUj%N
this.userService = userService; |C./gdq
} 7h/Mkim$5
} d>J
+7ex+
um PN=0u6
HHyN\
<AVWT+,
dn~k_J=p
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, D_F1<q
}:?_/$};
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 D'g@B.fXd
?jO<<@*2S
么只需要: 8}oe))b
java代码: -{L 7%j|R
r8y,$Mv<)0
'h&>K,U?5
<?xml version="1.0"?> f
4K)Z
e
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork } 5"Rj<
]\ZJaU80I~
1.0//EN" "http://www.opensymphony.com/xwork/xwork- I7XM2xM
toG- Dz&