Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Z\dILt:#z
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 "q]v2t
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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 {9C(\i +
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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 mv30xcc
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分页支持类: :%!SzI?
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java代码: hi.{
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package com.javaeye.common.util; 1
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import java.util.List; (<8T*Xo
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publicclass PaginationSupport { }Pw5*duq
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publicfinalstaticint PAGESIZE = 30; +S3'ms
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privateint pageSize = PAGESIZE; 4tq>Lx^5U
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privateList items; Odbjl[>k
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privateint totalCount; -$T5@
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privateint[] indexes = newint[0]; 4["}U1sG
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privateint startIndex = 0; czHO)uQ?d`
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public PaginationSupport(List items, int FWD9!M K
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totalCount){ ]B5\S
setPageSize(PAGESIZE); |
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setTotalCount(totalCount); MhJ`>.z1
setItems(items); B}?/oZW4
setStartIndex(0); KDn`XCnk,
} IE,g
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public PaginationSupport(List items, int -iJ[9O
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totalCount, int startIndex){ nQ/ha9v=n
setPageSize(PAGESIZE); yLY2_p-X
setTotalCount(totalCount); 6
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setItems(items); i\`[0dfY
setStartIndex(startIndex); wefQmRK
} UO!OO&l!
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public PaginationSupport(List items, int [IHT)%>E8&
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totalCount, int pageSize, int startIndex){ gbI0?G6XN/
setPageSize(pageSize); WOg_Pn9HI
setTotalCount(totalCount); : ;d&m
setItems(items); 9VP|a-
setStartIndex(startIndex); =e ;\I/
} jh=:Q P/
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publicList getItems(){ 5))?,YkrrI
return items; np)-Yzr
} v3hNvcMpf
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publicvoid setItems(List items){ .j;My%)?p
this.items = items; (xxJ^u>QC
} ,ciNoP*-~%
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publicint getPageSize(){ Oz n7C?\*
return pageSize;
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} 4RdpROK
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publicvoid setPageSize(int pageSize){ Q[g%((DL
this.pageSize = pageSize; ,Q}/#/
} OP<@Xz
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publicint getTotalCount(){ D* Vr)J
return totalCount; i:W
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} I5 [r-r
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publicvoid setTotalCount(int totalCount){ ;2bG-v'4vO
if(totalCount > 0){ /'ybl^Km
this.totalCount = totalCount; LkNfcBa_
int count = totalCount / 6,oi(RAf
;r`[6[AG
pageSize; ;/e!!P]jP
if(totalCount % pageSize > 0) *rW] HNz
count++; a{]1H4+bQ
indexes = newint[count]; FJ#V"|}
for(int i = 0; i < count; i++){ *]F3pP[
indexes = pageSize * J7mT&U&Ru
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i; >~XX'}
} 5#:tL&q
}else{ r:YAn^Lg
this.totalCount = 0; J }JT%SW
} t6js@Ih
} %L~X\M:Qk
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publicint[] getIndexes(){ l*%?C*
return indexes; `[Lap=.'.
} 6bfk4k
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publicvoid setIndexes(int[] indexes){ b6g,mzqu
this.indexes = indexes; xG<S2R2VQh
} `&0?e-
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publicint getStartIndex(){ orTTjV]_m
return startIndex; p>R F4
} Cr(pN[,
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publicvoid setStartIndex(int startIndex){ )\^%w9h
if(totalCount <= 0) H&%=>hyX
this.startIndex = 0; :G}tvFcOAF
elseif(startIndex >= totalCount) U7:~@eYy
this.startIndex = indexes ~|!q>z
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[indexes.length - 1]; uw]e$,x?
elseif(startIndex < 0) f1\x>W4z~\
this.startIndex = 0; nPv2: x
else{ s$Roe(J
this.startIndex = indexes VgoQz]z
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[startIndex / pageSize]; 85s{;3
} flb3Iih
} 5[*MT%ms
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publicint getNextIndex(){ 5^%^8o
int nextIndex = getStartIndex() + f \4Qp
[
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pageSize; kXG+zsT
if(nextIndex >= totalCount) a(}jn|
return getStartIndex(); X>Xpx<RY!
else r3*wH1n
return nextIndex; 7s[ ATu
} "@ox=
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publicint getPreviousIndex(){ auGt>,Zj\Q
int previousIndex = getStartIndex() - 06=eA0JI
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pageSize; heh!cDK
if(previousIndex < 0) 3K#e]zoI
return0; P-vA.7
else C-2n2OM.
return previousIndex; JG4&eK$-
} ,2?C^gxt
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} %Z}dY~:
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抽象业务类 Fx.uPY.a
java代码: /
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/** XRNL;X%}7
* Created on 2005-7-12 |L+GM"hg
*/ A"P1B]
package com.javaeye.common.business; 9r)5d&,6
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import java.io.Serializable; ~#j`+
import java.util.List; C3memimN
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import org.hibernate.Criteria; Y<M}'t
import org.hibernate.HibernateException; @B[=`9KF[
import org.hibernate.Session; GvVuF S>y
import org.hibernate.criterion.DetachedCriteria; XBeHyQp
import org.hibernate.criterion.Projections; DdFVOs|
import $hN!DHz
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org.springframework.orm.hibernate3.HibernateCallback; 4<O[d
import \tQi7yj4
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org.springframework.orm.hibernate3.support.HibernateDaoS #p[=iP
* dNMnZ@Y
upport; kPxrI=
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import com.javaeye.common.util.PaginationSupport; E*'O))
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public abstract class AbstractManager extends \K)q$E<!
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HibernateDaoSupport { ?}Mv5SO
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privateboolean cacheQueries = false; RZz] .Nx
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privateString queryCacheRegion; UkGUxQ,GU
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publicvoid setCacheQueries(boolean z24-hC
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cacheQueries){ 4e5Ka{# <
this.cacheQueries = cacheQueries; 'Y-c*q
} 2R1W[,Ga!
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publicvoid setQueryCacheRegion(String q=
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5ax/jd~}
queryCacheRegion){ \dCdyl6V
this.queryCacheRegion = <ZnAPh
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queryCacheRegion; KQ 2]VN"?_
} 'DKP-R"
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publicvoid save(finalObject entity){ #2`tsZ]=I
getHibernateTemplate().save(entity); f:=?"MX7
} S3n$
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publicvoid persist(finalObject entity){ )v'DQAL
getHibernateTemplate().save(entity); \K>6-0r|
} Ddu$49{S:
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publicvoid update(finalObject entity){ xvW+;3;
getHibernateTemplate().update(entity); 0BBWuNF.
} $A ( #^&
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publicvoid delete(finalObject entity){ 0/),ylCj
getHibernateTemplate().delete(entity); Q"\*JV5
} \=nY&Ml
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publicObject load(finalClass entity, /y1,w JI
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finalSerializable id){ uWgY+T
return getHibernateTemplate().load "&>$/b$
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(entity, id); *)"`v]
} ?-Oy/Y K
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publicObject get(finalClass entity, k(V#{
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finalSerializable id){ 3'IF?](]U
return getHibernateTemplate().get e)GFJ3sW_
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(entity, id); 5a_1x|Fhi
} k;q|pQ[
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publicList findAll(finalClass entity){ 1?Wk qQ
return getHibernateTemplate().find("from Z^s&]
cgml^k\k^
" + entity.getName()); D/Bb)]9I
} @G^
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publicList findByNamedQuery(finalString j<e`8ex?
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namedQuery){ FG'F]fc%
return getHibernateTemplate ?/5WM%
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().findByNamedQuery(namedQuery); c|IH|y
} 4f'1g1@$
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publicList findByNamedQuery(finalString query, !S$LRm\'
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finalObject parameter){ w<*6pPy
return getHibernateTemplate {p=`"H>
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().findByNamedQuery(query, parameter); ,l1A]Wx
} ZvM~]8m
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publicList findByNamedQuery(finalString query, R m>AU=
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finalObject[] parameters){ tHgu#k0
return getHibernateTemplate W+k SL{0
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().findByNamedQuery(query, parameters); 4,4S5u[|
} Wl\.*^`k
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publicList find(finalString query){ k[#<=G_=/E
return getHibernateTemplate().find FN0)DN2d}
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(query); oG{0{%*@
} _c$l@8KS^
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publicList find(finalString query, finalObject gc,%A'OR^<
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parameter){ $ S(<7[Z
return getHibernateTemplate().find S8>1l?UH
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(query, parameter); 2 8>
} 2zE gAc
= j)5kY`
public PaginationSupport findPageByCriteria inQ1$
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(final DetachedCriteria detachedCriteria){ &"lSq2
return findPageByCriteria 9696EQ,I
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); _"l2UDx
} T&'p5h=l
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public PaginationSupport findPageByCriteria 2Sgv
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(final DetachedCriteria detachedCriteria, finalint ?COLjk
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startIndex){ pGRk
return findPageByCriteria `_"loPu
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(detachedCriteria, PaginationSupport.PAGESIZE, {Qba`lOkq
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startIndex); Yj"{aFK#u@
} "UYlC0 S\
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public PaginationSupport findPageByCriteria tqD=)0Uzs
q x5jaa3
(final DetachedCriteria detachedCriteria, finalint l6T^e@*
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pageSize, 2`^M OGYk
finalint startIndex){ ]y9u5H^
return(PaginationSupport) {F=`IE3)w
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getHibernateTemplate().execute(new HibernateCallback(){ .QW@rV:T
publicObject doInHibernate j4wsDtmAU
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(Session session)throws HibernateException { Hkrh d
Criteria criteria = @$fvhEkrT@
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detachedCriteria.getExecutableCriteria(session); SuA
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int totalCount = f"-3'kqo
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((Integer) criteria.setProjection(Projections.rowCount )i"52!
5SEGV|%
()).uniqueResult()).intValue(); f5z*AeI
criteria.setProjection .npD<*
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(null); u
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List items = gI/SA
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criteria.setFirstResult(startIndex).setMaxResults BPSie0
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(pageSize).list(); Am<){&XT
]
PaginationSupport ps = x<5;#
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new PaginationSupport(items, totalCount, pageSize, %_(^BZd
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startIndex); ikb;,Js
return ps; S]ed96V v
} swg*fhJFB
}, true); %<>|cO
} 4|hfzCjMI
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public List findAllByCriteria(final O{Z
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DetachedCriteria detachedCriteria){ ft$
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return(List) getHibernateTemplate 82YZN5S3]3
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().execute(new HibernateCallback(){
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publicObject doInHibernate 7Q|v5@;pU
nu X`>Oy
(Session session)throws HibernateException { ahR-^^'$
Criteria criteria = 2U3WH.o
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detachedCriteria.getExecutableCriteria(session); 36d6KS 7
return criteria.list(); ^=
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} Lw6}bB`}
}, true); #&Zj6en}M]
} r#c+{yY
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public int getCountByCriteria(final zLjQ,Lp.I
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DetachedCriteria detachedCriteria){ Lmc"qFzK
Integer count = (Integer) 960rbxKy3
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getHibernateTemplate().execute(new HibernateCallback(){ ;h4w<OqcM
publicObject doInHibernate mam(h{f$
<< aAYkx<
(Session session)throws HibernateException { ?r R,
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Criteria criteria = Tl*FK?)MC^
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detachedCriteria.getExecutableCriteria(session); &Fl*,
return Gl5W4gW;&
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criteria.setProjection(Projections.rowCount k5)e7Lb(
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()).uniqueResult(); X-5&c$hv
} oHx =Cg;
}, true); "3VMjF\
return count.intValue(); 6n'XRfQp)&
} u )KtvC!
} !S[7IBk%
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用户在web层构造查询条件detachedCriteria,和可选的 T\o!^|8
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2~SjRIp Uw
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PaginationSupport的实例ps。 $,B@yiie
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ps.getItems()得到已分页好的结果集 |DMa2}%
ps.getIndexes()得到分页索引的数组 K~aIY0=<
ps.getTotalCount()得到总结果数 cdfvc0
ps.getStartIndex()当前分页索引 pZe:U;bb
ps.getNextIndex()下一页索引 LVp*YOq7
ps.getPreviousIndex()上一页索引 p*Hbc|?{Q&
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 y!?l;xMS
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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 L(i*v5?
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一下代码重构了。 4#BoS9d2I<
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我把原本我的做法也提供出来供大家讨论吧: P ME
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首先,为了实现分页查询,我封装了一个Page类: ;/8oP ;X2
java代码: 1k}U+
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/*Created on 2005-4-14*/ $G5;y>
package org.flyware.util.page; R1DXi
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/** 6KD
* @author Joa o(I[_oUy\
* (&G4@V d
*/ '_~=C-g
publicclass Page { 4S]`S\w
9
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/** imply if the page has previous page */ FN&.PdRT
privateboolean hasPrePage; TB
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/** imply if the page has next page */ I4Ys,n
privateboolean hasNextPage; ':fq
Gv!*
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/** the number of every page */ i[~oMwc&
privateint everyPage; s|U?{Byb!
MEQ:[;1
/** the total page number */ %:/_O*~)Yg
privateint totalPage; qF{u+Ms
a r#p7N
/** the number of current page */ ;2vHdN
privateint currentPage; (L?fYSP!
kne{Tp
/** the begin index of the records by the current Nt^R~#8hF>
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query */ "qRE1j@%a
privateint beginIndex; 9d4PH
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/** The default constructor */ j(!M
public Page(){ &UUIiQm~
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} 0+0+%#?
tt`j!!
/** construct the page by everyPage 3u7N/OQ(
* @param everyPage #N%xr'H
* */ ?9_<LE
q
public Page(int everyPage){ @eN x:}
this.everyPage = everyPage; 2l#Ogn`k
} 2*-s3 >VK
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/** The whole constructor */ wAxXK94#3
public Page(boolean hasPrePage, boolean hasNextPage, w4 <FC$
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m
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int everyPage, int totalPage, F_=RY]
int currentPage, int beginIndex){ +qe!KPk2
this.hasPrePage = hasPrePage; 1vBR\!d?7
this.hasNextPage = hasNextPage; , gk49z9
this.everyPage = everyPage; o`HZS|>K*
this.totalPage = totalPage; <Brq7:n|
this.currentPage = currentPage; aEVBU
this.beginIndex = beginIndex; [Z|R-{"
} kJqgY|
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/** v2:A 4Pd:+
* @return 1`N q
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* Returns the beginIndex. (,`ypD +3q
*/ &,2h=H,M
publicint getBeginIndex(){ 1HG~}E
return beginIndex; >tnQuFKg]
} 5BCXI8Ox9x
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/** ^4_)a0Kcm,
* @param beginIndex >6Y\CixN
* The beginIndex to set. `uy)][j-
*/ +M! f}=H
publicvoid setBeginIndex(int beginIndex){ jKZJ0`06q
this.beginIndex = beginIndex; tvynl;Y/
} \ Q<c Y<
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/** 7A?~a_Ep
* @return uyMxBc%6
* Returns the currentPage. LO<R<zz
*/ $^?"/;8P5
publicint getCurrentPage(){ `q7O\
return currentPage; lN#W
} UVlD]oXKh
#z_lBg. K
/** ED&>~~k)
* @param currentPage \\XvVi:B
* The currentPage to set. 0]=|3-n
*/ {/G~HoY1i
publicvoid setCurrentPage(int currentPage){ dO}6zQ\
this.currentPage = currentPage; `"zXf -qeE
} m(SGE,("w
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/** NpqMdd
* @return ;X,|I)
* Returns the everyPage. kx0(v1y3gT
*/ 42E]&=Cet
publicint getEveryPage(){ UZ7Zzc#g
return everyPage; lYldq)qB{
} ^N#B(F
T#kPn#|
/** }A,9`
* @param everyPage chk1tFV
* The everyPage to set. 2#LTd{
*/ vFm8 T58 7
publicvoid setEveryPage(int everyPage){ ]R[j]E.
this.everyPage = everyPage; V
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} K}7E;O5m"
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/** Qc1NLU9:
* @return hB/4.K ]8
* Returns the hasNextPage. ScOiOz:Ha
*/ n4 A_vz
publicboolean getHasNextPage(){ 7u7`z%
return hasNextPage; 1;8=,&
} :Z)a&A9v
yu3: Hv}
/** Q(v*I&k
* @param hasNextPage lz1RAp0R"
* The hasNextPage to set. S&(MR%".
*/ j#4 Iu&YJ
publicvoid setHasNextPage(boolean hasNextPage){ +I~`Ob
this.hasNextPage = hasNextPage; xE>H:YPm
} ]mIcK
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/** VPOzt7:
* @return yC#%fgQ r
* Returns the hasPrePage. 8(d Hn
*/ rdj_3Utv
publicboolean getHasPrePage(){ ]k+XL*]' A
return hasPrePage; ?X
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} .+ezcG4q
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/** >qE f991SZ
* @param hasPrePage hSAdD!
* The hasPrePage to set. <O<Kf:i&c1
*/ ,s ` y
publicvoid setHasPrePage(boolean hasPrePage){ uX/K/4
this.hasPrePage = hasPrePage; -d-vzri
} OdKfU^
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/** 8U8%XI EJ
* @return Returns the totalPage. T'^ Do/
* 6DkFI kS
*/ 7C;oMh5
publicint getTotalPage(){ }>93X0%r
return totalPage; r~[Bzw"c
} (r6'q0[
+DsdzR`Gx,
/** ;{L ~|q J
* @param totalPage cePe0\\
* The totalPage to set. 9ZJn 8ki
*/ F>F2Yql&W
publicvoid setTotalPage(int totalPage){ jT'09r3P
this.totalPage = totalPage; AONEUSxJ
} 0-P,zkK_v
Vb @lK~
} #}p@+rkg2
!jQj1QZR`
L*6R5i>
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PQd*)6K:A
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 (- D^_*f
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个PageUtil,负责对Page对象进行构造: \<aR^Sj.
java代码: f&L3M)T
i7XM7+}
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/*Created on 2005-4-14*/ 9,?7mgZp
package org.flyware.util.page; <*Gd0 v%
'" 4;;(
import org.apache.commons.logging.Log; Y'^+ KU
import org.apache.commons.logging.LogFactory; OWys`2W
p:NIRs
/** ,<(0T$o E[
* @author Joa im3BQIPR
* L,O.XR
*/ FeT|
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publicclass PageUtil { $KVCEe!X
8|{d1dy
privatestaticfinal Log logger = LogFactory.getLog Ya&\ b 6
sj 3[ny;b
(PageUtil.class); der\"?_.
+QEP:#qZw
/** sOO_J!bblP
* Use the origin page to create a new page P~*'/!@
* @param page }60/5HNr
* @param totalRecords "s.hO0Z
* @return E*x ct-m#
*/ JRR,ooN*i
publicstatic Page createPage(Page page, int ]1 jhy2j
^kK% 8 u
totalRecords){ %i.Prckrb
return createPage(page.getEveryPage(), +1]A$|qyW
#}Hdyl I\}
page.getCurrentPage(), totalRecords); twox.@"U
} NRT@"3,1YP
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/** qP$)V3l
* the basic page utils not including exception vSy[lB|)24
uD?Rs`
handler ,h9?o
* @param everyPage ZfXgVTJ`
* @param currentPage +{#L,0t
* @param totalRecords Ae%AG@L
* @return page h'+F'1=
*/ X/_89<&
publicstatic Page createPage(int everyPage, int n1x"B>3
=!G{+&j
currentPage, int totalRecords){ ~e&O?X
everyPage = getEveryPage(everyPage); Q_Wg4n5
currentPage = getCurrentPage(currentPage); yJ="dEn>i"
int beginIndex = getBeginIndex(everyPage, (*_lLM@Cd
{.?pl]Zl6
currentPage); 9o4h~Imu
int totalPage = getTotalPage(everyPage, (I#mo2
'
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totalRecords); H:P7G_!\
boolean hasNextPage = hasNextPage(currentPage, qi
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totalPage); ^ FM
boolean hasPrePage = hasPrePage(currentPage); !zsrORF{
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returnnew Page(hasPrePage, hasNextPage, |+KwyHE`9
everyPage, totalPage, %E"v@
currentPage, &F:.OVzX
%P{3c~?DH
beginIndex); -:kIIK
} M[+#*f.T}
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privatestaticint getEveryPage(int everyPage){ #WJ*)$A@&
return everyPage == 0 ? 10 : everyPage; ]1pB7XL
}
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D1$ER>
privatestaticint getCurrentPage(int currentPage){ E [6:}z<
return currentPage == 0 ? 1 : currentPage; r6R@"1/
} 3Fxr=
AWE ab
privatestaticint getBeginIndex(int everyPage, int Y%?*Lj|
ktS^^!,l%
currentPage){ Br15S};Ce
return(currentPage - 1) * everyPage; o(H.1ESk
} J3(E{w8Q
0\vG
<
privatestaticint getTotalPage(int everyPage, int U$<"
.q
6Ol9P56j
totalRecords){ 0:>hK\F#
int totalPage = 0; TVx
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K[
[6A:
if(totalRecords % everyPage == 0) vf$IF|
totalPage = totalRecords / everyPage; p:K%-^
else 0?(uqjD:
totalPage = totalRecords / everyPage + 1 ; q5L^>"
D/~1?p
return totalPage; q*|Alrm
} $B_%MfI
P"l'? `
privatestaticboolean hasPrePage(int currentPage){ eU@Mv5&6
return currentPage == 1 ? false : true; V=dOeuYd
} 9Li*L&B)
E5@ =LS
privatestaticboolean hasNextPage(int currentPage, vq^';<Wh.
F]P sS(
int totalPage){ Hz."4nhv
return currentPage == totalPage || totalPage == :i4(cap&}F
IQ~qiFCf
0 ? false : true; bT&{8a
} R:YVmqd
;nP(S`'
"n`z`{<n
} ;Tp9)UP)
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nEd
"~
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 hN6wp_
GT6i9*tb#
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 c/A?-9
xh$yXP0/
做法如下: t_w\k_
T
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 <
$e#o H
&Wcz~Gx3Q
的信息,和一个结果集List: 7Tdx*1 U
java代码: =<3HOOC
!zF07.(E
7<!x:G?C
/*Created on 2005-6-13*/ jaodcT0
package com.adt.bo; "WQ6[;&V
$j\>T@
import java.util.List; l3>e-kP
H
Eq{TUTr
import org.flyware.util.page.Page; 7uL.=th'
UHvA43
/** |~
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* @author Joa (9I(e^@]
*/ [BD`h
publicclass Result { g^+p7G
bKM*4M=k
private Page page; yP+<kv4
ZBpcC0
z
private List content; -o%? ]S
Vf pT5W<
/** uq s
* The default constructor zu{K"7Bx
*/ M9R'ONYAa
public Result(){ 9gw;MFP)D
super(); %AA&n*m
} Hq::F?
[?I<$f"
/** 3{?X>6T
* The constructor using fields Yft [)id
* TS|Bz2(
* @param page .cJoNl'q
* @param content %_5#2a
*/ ]-X6Cl
public Result(Page page, List content){ CdRJ@Lf
this.page = page; GxD`M2
this.content = content; ca7Y+9<
;
} e`g+Jf`AT
MZQDFuvDxZ
/** P1rjF:x[*
* @return Returns the content. xtP:Q9!N
*/ ) dk|S\
publicList getContent(){ 4Z%1eOR9V
return content; 3S+9LOrhY
}
%p
VBi gUK4
/** ]>(pj9)
* @return Returns the page. hQj@D\}
*/ >"!ScYn
public Page getPage(){ @!dIa1Q"
return page; Up?RN %gq
} q( ~rk
Rmmu#-{Y
/** ;&CLb`<y
* @param content =AzPAN#e
* The content to set. SZe55mK `
*/ _"Bj`5S
public void setContent(List content){ u@e.5_:S)
this.content = content; 1Mp-)-e
} uT,i&
,V!"4T,Z
/** \ZADY.ha
* @param page }#D=Rf?2\P
* The page to set. 7s6+I_n
*/ .5a>!B.I
publicvoid setPage(Page page){ [pTdeg;QE
this.page = page; c|.te]!ds
} fdKE1,;
} ZcjLv
!gW`xVGv
KJQ8Yhq
&J2UAmB
FhUi{`
2. 编写业务逻辑接口,并实现它(UserManager, 5]I)qij
q
lfDd%.:q4S
UserManagerImpl) &v .S_Ym
java代码: 1ygEyC[1
:5/Ue,~ag
~xxq.rL"
/*Created on 2005-7-15*/ %"
bI2
package com.adt.service; hOk9 y=
^yB]_*WJ
import net.sf.hibernate.HibernateException; Vv+nq_
kbb!2`F!%
import org.flyware.util.page.Page; u=InE|SH
9*s8%pL
import com.adt.bo.Result; N}U+K
3@x[M?$
/** 3v_j*wy
* @author Joa z8a{M$-Q
*/ x`7Le&4f
publicinterface UserManager { I= :yfW
YQ:$m5ai
public Result listUser(Page page)throws " J9
`uPO+2
HibernateException; aB~k8]q.
iWjNK"W
} [VXQ&
V z
)wjpxr
@Un/,-ck
geK;r0(f
java代码: #0r^<Yn
>(H:eRKq
6
DQOar>d
/*Created on 2005-7-15*/ gKTCfD~
package com.adt.service.impl; moFrNcso
-<x%
import java.util.List; a K6dy\
BKTTta1mY
import net.sf.hibernate.HibernateException; ]~
N.
:K~@JlJd
import org.flyware.util.page.Page; 66>X$nx(z
import org.flyware.util.page.PageUtil; ]vcT2lr]
FYik}wH]
import com.adt.bo.Result; RvA "ug.*
import com.adt.dao.UserDAO; bl!pKOY
import com.adt.exception.ObjectNotFoundException; 4IZAJqw(*
import com.adt.service.UserManager; Bkq4V$D_
%6lGRq{/?
/** JQ}4{k
* @author Joa Yqh-U%"'
*/ )M7yj O!
publicclass UserManagerImpl implements UserManager { #"A`:bjG
;FwUUKj
private UserDAO userDAO; ]GRVU
9mtndTT 5u
/** >N!
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* @param userDAO The userDAO to set. fGj66rMGw
*/ ~,s'-
publicvoid setUserDAO(UserDAO userDAO){ M1P;x._n
this.userDAO = userDAO; \l0!si
} s3ASA.*
8}[<3K%*g
/* (non-Javadoc) '$yy
* @see com.adt.service.UserManager#listUser 5![ ILa_
ec^{ez@`
(org.flyware.util.page.Page) <au_ S\n
*/ K
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public Result listUser(Page page)throws Qj
[p/H$
N>L)2WKFT
HibernateException, ObjectNotFoundException { qe1>UfY
int totalRecords = userDAO.getUserCount(); -
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if(totalRecords == 0) XH0Vs.w
throw new ObjectNotFoundException "<^
Vp-7r
Y -BZV |
("userNotExist"); 5't9/8i
page = PageUtil.createPage(page, totalRecords); ,,EG"Um6
List users = userDAO.getUserByPage(page); y4n~gTo(?
returnnew Result(page, users); OI/]Y7D[Oq
} *
kL>9
@/01MBs;
} fk2Uxg=[
# NK{]H$fd
Q.8^F
kiin7 8W
DB jUHirK
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 \Ym$to
[m
x}n+~
询,接下来编写UserDAO的代码: 7 oYD;li$k
3. UserDAO 和 UserDAOImpl: y
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java代码: rTC| 8e
\"yR[.Q?
|~Awm"
/*Created on 2005-7-15*/ ]/R>nT
package com.adt.dao; rhQO#_`
-%VFC^'5
import java.util.List; Np~qtR
-42 U
import org.flyware.util.page.Page; ]?jmRk^.
el^<M,7!
import net.sf.hibernate.HibernateException; ,=%c
e
BIvz55g
/** iVqF]2>
* @author Joa Xn<|6u
*/ b\t@vMJ
publicinterface UserDAO extends BaseDAO { &)~LGWBdC
J2`OJsMwWe
publicList getUserByName(String name)throws 1@<>GDB9
*EtC4sP
HibernateException; =\<!kJ\yH
Lr>4~1:`
publicint getUserCount()throws HibernateException; RQn3y-N]
Y7yzM1?t
publicList getUserByPage(Page page)throws & *&
%__.-;)o
HibernateException; 6tM@I`l
lU3Xd_v
O
} t2%gS"
[
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a@gm r%C
yj`xOncE}
odq3@
ziO
java代码: gem+$TFq
,PyPRPk
4b$m\hoN
/*Created on 2005-7-15*/ 7m9T'
package com.adt.dao.impl; O[')[uo8s
Tb]' b
import java.util.List; o&:n>:im
mZ
t:
import org.flyware.util.page.Page; 0EP8MR SR
M7IQJFra
import net.sf.hibernate.HibernateException; QmB,~x{j>
import net.sf.hibernate.Query; 27jZ~Bp$
L`Q9-#Y
import com.adt.dao.UserDAO; ;%aWA
_^0)T@
/** 4K*DEVS
* @author Joa s((_^yf
*/ z15QFVm
public class UserDAOImpl extends BaseDAOHibernateImpl =R\-mov$
ma4r/8Q
implements UserDAO { j2|!h%{nI
NBZ>xp[U
/* (non-Javadoc) ud.Bzg:/
* @see com.adt.dao.UserDAO#getUserByName V5ihplAk
u~d&<_Z
(java.lang.String) 6ypqnOTr
*/ A,s .<TG
publicList getUserByName(String name)throws 0#KB.2AP
M+TF0c
HibernateException { >taZw'
String querySentence = "FROM user in class >(HUW^T/9z
I2=Kq{
com.adt.po.User WHERE user.name=:name"; )Z 3fytY
Query query = getSession().createQuery 6Gs,-Kb:
W\<5'9LNb
(querySentence); t`mLZ
<X
query.setParameter("name", name); 1P\_3.V{
return query.list(); 7e"(]NC84
} !f\6=Z?>3
@]h#T4z'
/* (non-Javadoc) uL4@e
* @see com.adt.dao.UserDAO#getUserCount() n1W}h@>8
*/ L3~E*\cV
publicint getUserCount()throws HibernateException { KXFa<^\o
int count = 0; !<2*B^
String querySentence = "SELECT count(*) FROM :1>R~2
zj;y`ENj
user in class com.adt.po.User"; F<w/@.&m
Query query = getSession().createQuery &,&oTd.
a~~ "2LE`
(querySentence); /aJl0GL4!
count = ((Integer)query.iterate().next
D-4PEf
Dx[t?-
()).intValue(); 8`qw1dF
return count; %GS)9{T&
} UrxgKTry
&/, BFx"
/* (non-Javadoc) 3)g1e=\i$
* @see com.adt.dao.UserDAO#getUserByPage Ec6{?\
%3VwCuE
(org.flyware.util.page.Page) [*>@hx
*/ RGtUKr'
publicList getUserByPage(Page page)throws T
"G! H
r/O(EW#=8
HibernateException { 7F'61}qL
String querySentence = "FROM user in class 1^Zx-p3J
<$njU=YE&
com.adt.po.User"; ^?xXP=/
Query query = getSession().createQuery ;|/7o@$n
3G8uXB_`}
(querySentence); 6]gs{zG
query.setFirstResult(page.getBeginIndex()) `u-VGd\
.setMaxResults(page.getEveryPage()); J= |[G'
return query.list(); "rjJ"u1
} -RH ?FJ
=C\S6bF%
} \^-3)*r
?\#4`9
4'rk3nT8
Y!*,G]7
xG}eiUbM`
至此,一个完整的分页程序完成。前台的只需要调用 vPwDV_z k
0 q3<RX>M%
userManager.listUser(page)即可得到一个Page对象和结果集对象 b8v$*{
I@L-%#@R1
的综合体,而传入的参数page对象则可以由前台传入,如果用 6OTxtk
kxUGd)S
webwork,甚至可以直接在配置文件中指定。
BW\R
LL6f40hC
下面给出一个webwork调用示例: esu6iU@
java代码: WD?V1:>+
KuI>:i;
yMSRUQ
x
/*Created on 2005-6-17*/ dF.T6b
package com.adt.action.user; eNNgxQw>m
!s)$_tG
import java.util.List; 329xo03-[
WAdl@){
import org.apache.commons.logging.Log; FUcs=7c
import org.apache.commons.logging.LogFactory; {G{@bUG]p
import org.flyware.util.page.Page; @i)tQd!s
&gEu%s^wR
import com.adt.bo.Result; bo -Gh`
import com.adt.service.UserService; x)*/3[
import com.opensymphony.xwork.Action; vp_ $6
"+Qh,fTt
/** #/jHnRrQ
* @author Joa q2<J`G(tZ
*/ 2.lnT{
publicclass ListUser implementsAction{ /w!' [
R&alq
privatestaticfinal Log logger = LogFactory.getLog 4*9Dh
F#<PFT4i
(ListUser.class); .$OInh
Dps{[3Y+
private UserService userService; /Bwea];^Q
~fUSmc
private Page page; R$3JbR.
p.}[!!m P
privateList users; p4AXQuOP
|(H|2]b4=
/* S2s-TpjB<
* (non-Javadoc) &S-& 'ZAY
* 0,A?*CO
* @see com.opensymphony.xwork.Action#execute() O#U"c5%
*/ )
k2NF="o
publicString execute()throwsException{ 0$_imjZ
Result result = userService.listUser(page); ( gFA? aD<
page = result.getPage(); }mGD`5[`
users = result.getContent(); aKUr":z
return SUCCESS; T8(wzs
} ^+wzm2i
y;>I'e
/** !fV6KkV
* @return Returns the page. ^/BE=$E\
*/ [:=[QlvV
public Page getPage(){ ~R8yj(
return page; @}Z/{Z[@
} % b&BLXW
["IJh
/** ,Df36-74v5
* @return Returns the users. F@lpjW
*/ UKBMGzu2:
publicList getUsers(){ Sp )}
return users; "$'~=' [
} 6K y;1$
BT1'@qF
/** yk)j;i4@
* @param page 4Qo1f5>N
* The page to set. B<&_lG0s