Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ZP{<f~;
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 HxSq&j*F
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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 P q0%oz
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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 50_[n$tqE
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分页支持类: *4/FN TC
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java代码: WP2=1"X63
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package com.javaeye.common.util; %UAF~2]g
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import java.util.List; #u}%r{T
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publicclass PaginationSupport { pO_IUkt
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publicfinalstaticint PAGESIZE = 30; gk6UV2nE?
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privateint pageSize = PAGESIZE; )adV`V%=>
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privateList items; ,jOJ\WXP
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privateint totalCount; S=(<m%f
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privateint[] indexes = newint[0]; MB!9tju
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privateint startIndex = 0; V(_1q
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public PaginationSupport(List items, int V\o7KF
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totalCount){ RFMPh<Ac
setPageSize(PAGESIZE); SRwD`FF
setTotalCount(totalCount); #8|LPfA
setItems(items); i|J%jA
setStartIndex(0); /M_$4O;*@
} 8LbwEKl
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public PaginationSupport(List items, int &W,jR|B
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totalCount, int startIndex){ K#YQB3rX
setPageSize(PAGESIZE); .^?zdW
setTotalCount(totalCount); tO&ffZP8$
setItems(items); v8)"skVnFG
setStartIndex(startIndex); CuWJai:nQ;
} |@vkQ
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public PaginationSupport(List items, int gxN>q4z
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totalCount, int pageSize, int startIndex){ DcW?L^Mst
setPageSize(pageSize); <.Ws; HN}
setTotalCount(totalCount); 1Y|a:){G
setItems(items); j-":>}oW2.
setStartIndex(startIndex); yd).}@
} hW~.F
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publicList getItems(){ 83n%pS4x
return items; eXW|{asx
} $@>0;i::
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publicvoid setItems(List items){ BDTL5N
this.items = items; rW:krx9
} );$99t
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publicint getPageSize(){ rZ~w_DK*
return pageSize; flsejj$
} )h8}{*
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publicvoid setPageSize(int pageSize){ !cwZ*eM
this.pageSize = pageSize; qI+2,6
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} 2;8m0+tl
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publicint getTotalCount(){ >Icr4?zq
return totalCount; `#N/]4(j
} |_V(^b}
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publicvoid setTotalCount(int totalCount){ y0%1YY
if(totalCount > 0){ /ad9Q~nJ
this.totalCount = totalCount; rO'DT{Yt
int count = totalCount / 5~L]zE
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pageSize; |A%9c.DG.
if(totalCount % pageSize > 0)
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count++;
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indexes = newint[count]; FACw;/rW
for(int i = 0; i < count; i++){ i[o 2(d,
indexes = pageSize * s6!6Oqh
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i; n0xGIq
} Oynb"T&8
}else{ EY,jy]|#
this.totalCount = 0; ^[M{s(b
} 'X^auyL
} Y`;}w}EcgR
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publicint[] getIndexes(){ FSIiw#xzH
return indexes; 5(3O/C{?~
} +0'F@l
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publicvoid setIndexes(int[] indexes){ CSO'``16
this.indexes = indexes; &{}Mds
} jJy:/!i
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publicint getStartIndex(){ S+ kq1R
return startIndex; )cqD"> vs
} F (*B1J2_g
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publicvoid setStartIndex(int startIndex){ $[ {5+ *
if(totalCount <= 0) g7 \=
this.startIndex = 0; &Y{^yb
elseif(startIndex >= totalCount) }LzBo\
this.startIndex = indexes JVZ-nHf(9
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[indexes.length - 1]; /jY
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elseif(startIndex < 0) Yj%]|E-
this.startIndex = 0; a.Ho>(V/4
else{ ^*K=wE}AG
this.startIndex = indexes r|Ui1f5
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[startIndex / pageSize]; . %RM8
} b)LT[>f
} L:z0cvn"
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publicint getNextIndex(){ D|]BFu)F
int nextIndex = getStartIndex() + eqbN_$>
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pageSize; Shm> r@C?
if(nextIndex >= totalCount) /^.|m3
return getStartIndex(); KZm&sk=QM-
else _yg_?GH
return nextIndex; ^L[:DB{Z
} 2jsbg{QS#_
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publicint getPreviousIndex(){ <W4F`6`x
int previousIndex = getStartIndex() - d9N[f>
}9~^}99}
pageSize; 7=!9kk 0
if(previousIndex < 0) wPA^nZ^}9c
return0; $l7^-SK`E
else 64s;EC
return previousIndex; AK:cDKBO
} $[gN#QW%
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} Vwkvu&4
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抽象业务类 q7R]!zk
java代码: +$2{u_m,
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/** rP@#_(22
* Created on 2005-7-12 p>6`jr
*/ O9=/\Kc
package com.javaeye.common.business; ,_[x|8m
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import java.io.Serializable; "M I';6
import java.util.List; A1WUK=P
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import org.hibernate.Criteria; $TQhr#C]
import org.hibernate.HibernateException; &!!*xv-z
import org.hibernate.Session; 5> k:PKHL
import org.hibernate.criterion.DetachedCriteria; ?jx]%n fV
import org.hibernate.criterion.Projections; VF]AH}H8I
import nm'l}/Ug
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org.springframework.orm.hibernate3.HibernateCallback; _z\/{
import /d`"WK,
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org.springframework.orm.hibernate3.support.HibernateDaoS fgLjF,Y
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upport; / 3A6xPOg
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import com.javaeye.common.util.PaginationSupport; +y7z>Fwl
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public abstract class AbstractManager extends kaG/8G(
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HibernateDaoSupport { FDHW'OP4
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privateboolean cacheQueries = false; ;KeU f(tH
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privateString queryCacheRegion; z>x@o}#u\|
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publicvoid setCacheQueries(boolean . "Ms7=
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cacheQueries){ JA^o/%a^
this.cacheQueries = cacheQueries; ^X#y'odtbS
} RObnu*
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publicvoid setQueryCacheRegion(String @[GV0*yz$
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queryCacheRegion){ +pofN-*%
this.queryCacheRegion = >{#JIG.
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queryCacheRegion; \pmS*Dt
} K$E3RB_F
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publicvoid save(finalObject entity){ T j$'B[cv
getHibernateTemplate().save(entity); Rr) 5[
} B2`S0 H
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publicvoid persist(finalObject entity){ @]\fO)\f
getHibernateTemplate().save(entity); '&>"`q
} `lhw*{3A
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publicvoid update(finalObject entity){ exRw, Nk4
getHibernateTemplate().update(entity); 7DB_Z/uU
} ,_z79tC{s
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publicvoid delete(finalObject entity){ [KDxB>R<{
getHibernateTemplate().delete(entity); `e[S Zj\
}
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publicObject load(finalClass entity, Hv,|XE@Y
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finalSerializable id){ pR0[qsQM
return getHibernateTemplate().load ,Oo`*'a[o7
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(entity, id); 0K!3Ny9(
} eJDZ|$
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publicObject get(finalClass entity, 0<M-asI?
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finalSerializable id){ $8EEtr,!
return getHibernateTemplate().get 1gI7$y+?
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(entity, id); Vk5Z[w a
} C@M-_Ud>Q
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publicList findAll(finalClass entity){ ,67Q!/O
return getHibernateTemplate().find("from A40DbD\^ad
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" + entity.getName()); (;NJ<x
} ChBf:`e
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publicList findByNamedQuery(finalString Ee>VA_ss
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namedQuery){ ?hoOSur+
return getHibernateTemplate A(Ct^/x-
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().findByNamedQuery(namedQuery); Mz+I
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} ULx:2jz
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publicList findByNamedQuery(finalString query, kG^76dAQL
n ]%2Kx
finalObject parameter){ ucCf%T\:
return getHibernateTemplate mh+T!v$[n)
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().findByNamedQuery(query, parameter); I}$`gUXX8x
} '|yx B')
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publicList findByNamedQuery(finalString query, *,u3Wm|7
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finalObject[] parameters){ ,05PYBc3
return getHibernateTemplate y<`5
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().findByNamedQuery(query, parameters); @2(u=E: ^
} )"x6V""Rb
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publicList find(finalString query){ 8 t+eu O
return getHibernateTemplate().find /<[0o]
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(query); jCd]ENl+_
} DYX{v`>f^
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publicList find(finalString query, finalObject F`=p/IAJK
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parameter){ S!K<kn`E3
return getHibernateTemplate().find U1\EwBK8*T
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(query, parameter); dJuy Jl$*
} *tjaac;z<J
@f[-
public PaginationSupport findPageByCriteria '1u?-2
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(final DetachedCriteria detachedCriteria){ QE 4
return findPageByCriteria /*C!]Z>.
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ir;JYY!0?
} (g6e5Sgi>
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public PaginationSupport findPageByCriteria 5:PS74/
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(final DetachedCriteria detachedCriteria, finalint p.:651b
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startIndex){ 5Fy dh0.
return findPageByCriteria @ZEBtM%.O
|# 0'_
(detachedCriteria, PaginationSupport.PAGESIZE, 'Oa3
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startIndex); . _+cvXy
} t{;2$z 0
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public PaginationSupport findPageByCriteria [^!SkQ
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(final DetachedCriteria detachedCriteria, finalint `IN!#b+Eo
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pageSize, FNGa4
finalint startIndex){ bH+NRNI]
return(PaginationSupport) VQIvu)I
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getHibernateTemplate().execute(new HibernateCallback(){ @Y0ZW't
publicObject doInHibernate
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(Session session)throws HibernateException { 3f=ZNJ>
Criteria criteria = sY<UJlDKT
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detachedCriteria.getExecutableCriteria(session); =gF035
int totalCount = 6R :hs C$
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((Integer) criteria.setProjection(Projections.rowCount zJXK:/
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()).uniqueResult()).intValue(); ):N#X<b':
criteria.setProjection Jp jHbG
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(null); [aSuEu?mC
List items = @x `X|>&
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criteria.setFirstResult(startIndex).setMaxResults 2ZxhV4\
1zRYd`IPoq
(pageSize).list(); l]G
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PaginationSupport ps = 628iN%[-
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new PaginationSupport(items, totalCount, pageSize, #cQ5-R-1
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startIndex); <zCWLj3
return ps; 6B]=\H
} |!FQQ(1b
}, true); l/3=o}8q
} ^cZ< .d2
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public List findAllByCriteria(final _DxHJl
)\yK61aX
DetachedCriteria detachedCriteria){ 6UCF w>
return(List) getHibernateTemplate 0"7+;(\1Rk
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().execute(new HibernateCallback(){ s AFn.W
publicObject doInHibernate &~2m@X(o
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(Session session)throws HibernateException { K/9Jx(I,qL
Criteria criteria = Cl'$*h
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detachedCriteria.getExecutableCriteria(session); rC@VMe|0
return criteria.list(); ;PaU"z+Je~
} NU=2*gM
}, true); FS}b9sQ)
} }etdXO_^
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public int getCountByCriteria(final k86TlQRh
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DetachedCriteria detachedCriteria){ 89>}`:xS^
Integer count = (Integer) af<h2r
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getHibernateTemplate().execute(new HibernateCallback(){ N]FRL\K
publicObject doInHibernate yF\yxdUX#
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(Session session)throws HibernateException { 3qTr|8`s
Criteria criteria = t
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detachedCriteria.getExecutableCriteria(session); Q u2
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return , >aa2
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criteria.setProjection(Projections.rowCount +a39 !j
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()).uniqueResult(); "BsK'yo.
} ^g4Gw6q6
}, true); PVg<Ovi^d
return count.intValue(); ' pgPQM<
} ZBDF>u@
} JPF6zzl)
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用户在web层构造查询条件detachedCriteria,和可选的 cFc(HADM`r
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <O7!(
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PaginationSupport的实例ps。 =/K)hI!u
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ps.getItems()得到已分页好的结果集 T1qbb*
ps.getIndexes()得到分页索引的数组 .1TuHC\mC
ps.getTotalCount()得到总结果数 W`PJflr|
ps.getStartIndex()当前分页索引 YyYZD{^
ps.getNextIndex()下一页索引 9h|6"6
ps.getPreviousIndex()上一页索引 |!]
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 >SQzE
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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 N
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一下代码重构了。 6 eryf?
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我把原本我的做法也提供出来供大家讨论吧: Xk.OyQ@
K ,NmDc^
首先,为了实现分页查询,我封装了一个Page类: 8Azh&c
java代码: ,r*Kxy
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/*Created on 2005-4-14*/ fD@d.8nXd
package org.flyware.util.page; Xr=BxBttp
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/** Yw#fQFm
* @author Joa 9vP;i= fr
* 7)QZ<fme
*/ kf>3T@
publicclass Page { 8OZasf
=q0V%h{
/** imply if the page has previous page */ ( 0/M?YQF
privateboolean hasPrePage;
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/** imply if the page has next page */ VOD-<
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privateboolean hasNextPage; )1!<<;@0
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/** the number of every page */ 27N;>
privateint everyPage; a%.W9=h=M(
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/** the total page number */ s8&q8r7%
privateint totalPage; EtzSaB*|
{Vj&i.2,
/** the number of current page */ W]/J]O6
privateint currentPage; i[9yu-
B>c$AS\5y
/** the begin index of the records by the current D(ItNMcKu
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query */ Y >w7%N
privateint beginIndex; dJ
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/** The default constructor */ s1Acl\l-uF
public Page(){ !DOyOTR&3
by'KJxl[
} beo(7,=&
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/** construct the page by everyPage >I\B_q
* @param everyPage Q&.uL}R
* */ 0zNbux_
public Page(int everyPage){ @\w}p E
this.everyPage = everyPage; {)"[_<
} \1G'{#Q
u ,3B[
/** The whole constructor */ W9]z]6
public Page(boolean hasPrePage, boolean hasNextPage, BeLD`4K
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int everyPage, int totalPage, DAb/B
int currentPage, int beginIndex){ r|UJJ9i
this.hasPrePage = hasPrePage; tgKr*8t{
this.hasNextPage = hasNextPage; pM@8T25=
this.everyPage = everyPage; GqxnB k1
this.totalPage = totalPage; dvjj"F'Bf
this.currentPage = currentPage; UgAp9$=z
this.beginIndex = beginIndex; GIzB1cl:
} OU UV8K
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/** D<69xT,
* @return rb-ao\
* Returns the beginIndex. y#B=9Ri=z
*/ U\Vg &"P
publicint getBeginIndex(){
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return beginIndex; 9oJM?&i
} ns>$
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/** Cd)g8<
* @param beginIndex S?b&4\:
* The beginIndex to set. .4^+q9M
*/ f;^ +q-Q
publicvoid setBeginIndex(int beginIndex){ :
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this.beginIndex = beginIndex; qm!cv;}c1
} =!q]0#
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/** fX`u"`o5
* @return 3XlQ 4
* Returns the currentPage. 0RA#Y(IR
*/ )&_bY~P
publicint getCurrentPage(){ GKIzU^f
return currentPage; vU,7Y|t`
} #aL.E(%
g)czJ=T2
/** P}8hK
* @param currentPage ]|g2V
a~-
* The currentPage to set. <8 <P,
*/ =h4uN,
publicvoid setCurrentPage(int currentPage){ LSc^3=X
this.currentPage = currentPage; _MC',p&
} !6-t_S
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/** @`KbzN_h/
* @return *,G<X^
* Returns the everyPage. I[&x-}w
*/ Jn{)CZ
publicint getEveryPage(){ Z0Sqw
return everyPage; |_p7vl"
} &6CDIxH{
esTL3 l{[
/** WDghlC6g!l
* @param everyPage 5/P. 4<c7
* The everyPage to set. @I4HpY7:
*/ o=Z:0Ukl]
publicvoid setEveryPage(int everyPage){ L;:PeYPL
this.everyPage = everyPage; uxxk&+M
} ub8d]GZJ
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/** 17'd~-lE
* @return t8RtJ2;
* Returns the hasNextPage. eg*a Vb
*/ )8^E{w^D}
publicboolean getHasNextPage(){ T^^7@\vDI
return hasNextPage; (enr{1
}
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/** 4Mg%}/cC
* @param hasNextPage $)*qoV
* The hasNextPage to set. A v>v\ :.>
*/ %G(VYCeK
publicvoid setHasNextPage(boolean hasNextPage){ :7X4VHw/
this.hasNextPage = hasNextPage; RDSC @3%
} l7T?Yx j
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/** ?wkT=mv
* @return G!VEV3zT
* Returns the hasPrePage. W>!:K^8]
*/ !j7mY9x+
publicboolean getHasPrePage(){ ]+,L/P
return hasPrePage; 2<UC^vZ
} ]/h$6mrL
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/** nL^7t7mp
* @param hasPrePage `%[m%Y9h
* The hasPrePage to set. c86?-u')
*/ <=|^\r
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publicvoid setHasPrePage(boolean hasPrePage){ 1:<n(?5JI
this.hasPrePage = hasPrePage; p}==aNZK
} "a;$uW@.6
7@ONCG
/** S^~"#
* @return Returns the totalPage. , SUx!o
* F}mt
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*/ GTbV5{Ss
publicint getTotalPage(){ E2}X[EoBF
return totalPage; KJ/Gv#Kj
} &jEw(P&_
b&E"r*i|
/**
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* @param totalPage J0k!&d8
* The totalPage to set. Tr>_R%b K
*/ 9E5*%Hu_
publicvoid setTotalPage(int totalPage){ yT<"?S>D
this.totalPage = totalPage; n'vdA !R
} GBZ u<t/
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} z+oy#p6+F.
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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 xC
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个PageUtil,负责对Page对象进行构造: lrkgsv6
java代码: LsGO~EiJ
3`D*AFQc
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/*Created on 2005-4-14*/ Jon3ywd1Y
package org.flyware.util.page; 21<Sfsc$
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import org.apache.commons.logging.Log; Y[b08{/
import org.apache.commons.logging.LogFactory; xv>8rW(Np5
9`qw,X&AK_
/** kn$SG
* @author Joa Ot=nKdP}D
* 9:%')M&Q
*/ )X *_oH=
publicclass PageUtil { 1)}hzA
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privatestaticfinal Log logger = LogFactory.getLog Q>X1 :Zn3
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(PageUtil.class); zO9WqP_`iR
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/** Tl"r#
* Use the origin page to create a new page vfT
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* @param page iX2exJto
* @param totalRecords KX\=wFbP)
* @return E rA*a3
*/ 9;*B*S~znW
publicstatic Page createPage(Page page, int DV?c%z`YO
ae3 Gn}tf
totalRecords){ LD WYFOGQ
return createPage(page.getEveryPage(), sjLm-pn3
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page.getCurrentPage(), totalRecords); 6e,IjocsB
} m bhh
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/** (:H4
* the basic page utils not including exception oKkDG|IE
wE9z@\z]
handler R'_F9\
* @param everyPage m/g[9Y
* @param currentPage ,Cm1~ExJ
* @param totalRecords ;)f,A)(Z
* @return page asvM/ 9
*/ 3# 0Nd"/0
publicstatic Page createPage(int everyPage, int P_Gu~B!Y
OWr\$lm@z$
currentPage, int totalRecords){ H2g#'SK@
everyPage = getEveryPage(everyPage); {P?p*2J'
currentPage = getCurrentPage(currentPage); Hjs#p{t[
int beginIndex = getBeginIndex(everyPage, btC<>(kl&
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currentPage); NeEV=+<-G
int totalPage = getTotalPage(everyPage, hG<W*g
R4[|f0l}s
totalRecords); #8v l2qWbi
boolean hasNextPage = hasNextPage(currentPage, -idbR[1{?
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totalPage); j}}as
boolean hasPrePage = hasPrePage(currentPage); _w <6o<@
e9k$5ps
returnnew Page(hasPrePage, hasNextPage, S}/ZHo
everyPage, totalPage, Y)S
f;
currentPage, QUXr#!rPY|
XGnC8Be{4
beginIndex); R6GlQ G
} hR[_1vuIu
ey>tUmt6?
privatestaticint getEveryPage(int everyPage){ L?(1
[jB4G
return everyPage == 0 ? 10 : everyPage; T-oUcuQB
} |BbrB[+ v[
h!Fh@%
privatestaticint getCurrentPage(int currentPage){ Rh@UxNy\,
return currentPage == 0 ? 1 : currentPage; 8"wavh|g4
} ll"6KI'X
KAy uv
privatestaticint getBeginIndex(int everyPage, int ;,KT+!H$
4kNSF
currentPage){ ^!(tc=sr
return(currentPage - 1) * everyPage; Q;z'"P
} )Y1+F,C
,I f9w$(z
privatestaticint getTotalPage(int everyPage, int W\ARCcTQ
))6iVgSE$
totalRecords){ kQ6YQsJ.*
int totalPage = 0; J<iiA:&J
`LTD|0;
if(totalRecords % everyPage == 0) V8%( h[
totalPage = totalRecords / everyPage; riglEA[^
else FePWr7Ze
totalPage = totalRecords / everyPage + 1 ; RDqQ6(e"
:WSszak
return totalPage; y8di-d3_
} ;ejtP #$
j{%'A
privatestaticboolean hasPrePage(int currentPage){ 8;,(D#p
return currentPage == 1 ? false : true; `C*psS
} ARB^]
j4D`Xq2X
privatestaticboolean hasNextPage(int currentPage, Zr!CT5C5
te3\MSv;O
int totalPage){ !V0)eC50
return currentPage == totalPage || totalPage == y[f6J3/
0ARj3
0 ? false : true; A LR`z~1
} &nn+X%m9g
5[+E?4,&
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} hQJ-
~
2\xEMec
tjDCfJx*
w}(Ht_6q{
&K,rNH'R
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。 +d8?=LX
JZrZDW>M
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 B}h8c
J#k.!]r,Y
做法如下: ^;mGOjS
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 rx(z::
q9m-d-!)
的信息,和一个结果集List: }/-TT0*6j<
java代码: 0\Myhh~DLE
N07FU\<9
J*f..:m
/*Created on 2005-6-13*/ LsV?b*^(p
package com.adt.bo; R%%h=]
n0@ \x=9
import java.util.List; + gP 4MP
@1peJJ{
import org.flyware.util.page.Page; }mQh^
*| YR8f
/** 'y:+w{I2o
* @author Joa /{\mV(F(
*/ ( |Xc_nC
publicclass Result { pH!8vnoA
-*"Q-GO
private Page page; q+Qrc]>-f
~_yz\;#
private List content; Z=/bD*\g
|^kfa_d
/** mwqe@7
* The default constructor ew6\Z$1c~
*/ .Vb\f
public Result(){ 2/G`ej!*
super(); \}})U#
} <-a6'g2y
MF~Tr0tOC
/** 08 aZU
* The constructor using fields f{u3RCfX~2
* ejPK-jxCa/
* @param page )3KQ
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* @param content "DNiVL.
*/ yBwCFn.uP-
public Result(Page page, List content){ r081.<
this.page = page; &o*f*(C2
this.content = content; [H2"z\\u
} g6 T /k7a
1W2hd!J7C
/** {nlqQ.jO
* @return Returns the content. x*z$4)RP
*/ Lr`G. e
publicList getContent(){ El`f>o+EJ
return content; aY@st]p
} lip1wR7
ax+P)yz
/** h"+|)'*n
* @return Returns the page. OQm-BL
*/ FYu=e?L
public Page getPage(){ XDrNc!XN
return page; 4^rO K
} J$Nc9?|ZZ
7|eD}=jy
/** H-aSLc
* @param content WAt | J2
* The content to set. /5c;,.hm1R
*/ Y^W.gGM
public void setContent(List content){ $s-HG[lX[
this.content = content; \+B+M 7
} G_UxR9Qo
C 9:5c@G
/** e^ygQ<6%
* @param page s9-aPcA
* The page to set. F)g.xQ
*/ 92HxZ*t7km
publicvoid setPage(Page page){ AmmUoS\
this.page = page; g` QbJ61a
} ]ZOzqh_0C
} `CXAE0Fx
E
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SecZ5(+=
- &/n[EE
+WP
2. 编写业务逻辑接口,并实现它(UserManager, m!-,K8
H7"m/Bia
UserManagerImpl) <_"^eF+fZ
java代码: J3B]JttU
T m0m$l
BejeFV3
/*Created on 2005-7-15*/ 7 Ed6o
package com.adt.service; T] tG,W1>i
[:!D.@h|
import net.sf.hibernate.HibernateException; hVAP
) "5
^KK6 d
import org.flyware.util.page.Page; a:(.{z?nM
s1eGItx[w
import com.adt.bo.Result; g
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m
pWmExQ
/** K8UgP?c;0
* @author Joa elBmF#,j7
*/ .v3~2r*&
publicinterface UserManager { YQI&8~z
. !|3a
public Result listUser(Page page)throws ,\BGxGNAmV
XfXqq[\N
HibernateException; pU |SUM
{)QSxO
} *MEDV1l_T
n"1LVJN7
z5G$'
clZjb
q!
+?
java代码: C?3?<FDL
[o=v"s't)
J \@yP
/*Created on 2005-7-15*/ 2Rp5 E^s
package com.adt.service.impl; .7*3V6h =F
~fE6g3
import java.util.List; Zw[A1!T,
;{e ;6Hq
import net.sf.hibernate.HibernateException; 9(>l trA
S"Dw8_y7}
import org.flyware.util.page.Page; cb k|LQ.O
import org.flyware.util.page.PageUtil; ?
D?XaRb
De>'
import com.adt.bo.Result; nSL
x1Q
import com.adt.dao.UserDAO; D4x~Vk%H
import com.adt.exception.ObjectNotFoundException; x*A_1_A
import com.adt.service.UserManager; Ifm|_
8tM40/U$
/** DJv;ed%x
* @author Joa `&"-|
*/ :Qg3B ';
publicclass UserManagerImpl implements UserManager { 52$7vYMto
Dwq }O
private UserDAO userDAO; e)[>E\u _
j z aC
/** sz' IGy%
* @param userDAO The userDAO to set. KMxP%dV/=
*/ "YUyM5X
publicvoid setUserDAO(UserDAO userDAO){ lqO"
this.userDAO = userDAO; {o?+T);Z
} 6}YWM]c%
D|u! KH
/* (non-Javadoc) 0{/P1
* @see com.adt.service.UserManager#listUser |(E.Sb
pr2b<(Pm
(org.flyware.util.page.Page) `JGV3nN
*/ 2\xv Yf-
public Result listUser(Page page)throws 3%<Uq%pJ
L,&R0gxi
HibernateException, ObjectNotFoundException { LV'@JFT-
int totalRecords = userDAO.getUserCount(); 9Se7
1
if(totalRecords == 0) HCh;Xi
throw new ObjectNotFoundException asDq(J`sQ
'Jb6CRn
("userNotExist"); MX%D%}N
page = PageUtil.createPage(page, totalRecords); b5hJaXJN
List users = userDAO.getUserByPage(page); ,7mRb-*p
returnnew Result(page, users); (Yzy;"iAu
} %E95R8SL
:GU6v4u
} edh?I1/
*RQkL'tRf
"JLKO${ Y
Im;8Abf
9{?L3V!+r
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 }nDKSC/[V!
JfmNI~%
询,接下来编写UserDAO的代码: oJ cR)H
3. UserDAO 和 UserDAOImpl: KLI(Rve24
java代码: '2u(fLq3h
!$"DD[~\
`.f
{V
/*Created on 2005-7-15*/ |fMjg'%{}
package com.adt.dao; c5K@<=?,E
_`>F>aP
import java.util.List; D}SYv})Ti
EK^B=)q6:W
import org.flyware.util.page.Page; 7q&//*%yF
9]AiaV9
import net.sf.hibernate.HibernateException; biCX:m+_?
3Zm'09A-.
/** _c=[P@
* @author Joa h&3*O[`
*/ Ex'6 WN~kD
publicinterface UserDAO extends BaseDAO { gO*:<B g
v$R+5_@[l
publicList getUserByName(String name)throws FhZ^/= As
i<N[s O
HibernateException; _~aFzM
D-7PO3F:F
publicint getUserCount()throws HibernateException; *x EcX6ZHX
93="sS
publicList getUserByPage(Page page)throws &UhI1mi]h
?UC3ES
HibernateException; _pSCv:3T
=&QC&CqEi
} J`U\3:b`SP
X|'E yZ
|=C&JA
P@ewr}
@add'>)
java代码: Ju""i4
{Mc^[}9
:` >|N|i
/*Created on 2005-7-15*/ V[<]BOM\v
package com.adt.dao.impl; j?&Rf,,%
2 %YtMkC5
import java.util.List; >uS?Nz5/
bi:m;R
import org.flyware.util.page.Page; {EKzPr/
bT|NZ!V
import net.sf.hibernate.HibernateException; mX78Av.z!
import net.sf.hibernate.Query; 1Ih.?7}
I\JJ7/S`t
import com.adt.dao.UserDAO; 5!2^|y4r
*Mf;
/** =VMV^[&>
* @author Joa O j<.3U[C
*/ 8+no>%L
public class UserDAOImpl extends BaseDAOHibernateImpl GE`:bC3
49%qBO$R
implements UserDAO { @SREyqC4
Vvuw gJX
/* (non-Javadoc) +.N3kH
* @see com.adt.dao.UserDAO#getUserByName 0MK|spc
!xs.[&u8
(java.lang.String) rixP[`!]x
*/ h+e Oe}
publicList getUserByName(String name)throws si.A"\bm
|oq27*ix~m
HibernateException { 4q"x|}a
String querySentence = "FROM user in class aRBTuLa)fo
}`g:)gJ
com.adt.po.User WHERE user.name=:name"; ?{s!.U[T@
Query query = getSession().createQuery 7 jq?zS|
5Xn+cw*
(querySentence); 'p=5hsG
query.setParameter("name", name); "mbcZ5_
return query.list(); G%
wVQ|1
} 7XKPC+)1ya
Vv=/{31
/* (non-Javadoc) AV0m31b
* @see com.adt.dao.UserDAO#getUserCount() %T]NM3|U
*/ IwC4fcZX6
publicint getUserCount()throws HibernateException { 0be1aY;m&
int count = 0; ]3@6o*R;
String querySentence = "SELECT count(*) FROM pkjf5DWp
I@VhxJh
user in class com.adt.po.User"; iB[>uW
Query query = getSession().createQuery }mRus<Ax
>
Y
<in/
(querySentence);
`ReTfz;o
count = ((Integer)query.iterate().next QJc3@
TJ@@kSSbl
()).intValue(); 3F' {JP
return count; H`/QhE
} W=T3spV
5'f4=J$Z)
/* (non-Javadoc) Z$R6'EUb1
* @see com.adt.dao.UserDAO#getUserByPage /\L|F?+@
R<VNbm;
(org.flyware.util.page.Page) -.A%c(|Q
*/ P(I`^x
publicList getUserByPage(Page page)throws 5~T`R~Uqb
BKDs3?&
HibernateException { {9sA'5
String querySentence = "FROM user in class )Lht}I ]:
I`"8}d@Jm
com.adt.po.User"; J+f
.r|?
Query query = getSession().createQuery rj qX|
Ju3-ZFUS4
(querySentence); "0o1M\6Z
query.setFirstResult(page.getBeginIndex()) aY 8"Sw|4
.setMaxResults(page.getEveryPage()); >jEn>H?
return query.list(); Xz)UH<
}
'Eds0"3
-x~h.s,
} h8;B +#f`
#:0dqD=
1{N73]-M:
`YTagUq7
70NQ9*AAy
至此,一个完整的分页程序完成。前台的只需要调用 g z!q
y+f@8]
userManager.listUser(page)即可得到一个Page对象和结果集对象 ( lbF/F>v
oJC-?
的综合体,而传入的参数page对象则可以由前台传入,如果用 OgJd^
su]CaHU
webwork,甚至可以直接在配置文件中指定。 tydD~a
GOJ*>GpS
下面给出一个webwork调用示例: cU8Rm\?
java代码: BrYU*aPW;
,4oYKJ$+h
x2p}0N
/*Created on 2005-6-17*/ 7%?2>t3~
package com.adt.action.user; 7'wt/9
~=h M y`Ml
import java.util.List; :.kc1_veYS
(_G&S~@.
import org.apache.commons.logging.Log; ;h[p "
import org.apache.commons.logging.LogFactory; } ).rD
import org.flyware.util.page.Page; Fu4LD-#
&$yC+cf
import com.adt.bo.Result; n4Fh*d ixg
import com.adt.service.UserService; 8A/;a{
import com.opensymphony.xwork.Action; Wyu$J
4Q2=\-KFj
/** }7iWm XlI
* @author Joa PI{;3X}9$,
*/ ;J|sH>i
publicclass ListUser implementsAction{ *,$cW,LN
9(?9yFbj5
privatestaticfinal Log logger = LogFactory.getLog Cz=HxU80J
E$5)]<p! <
(ListUser.class); s*`_Ka57]~
>ZMB}pt`
private UserService userService; 4;anoqiG\
M@$}Og
private Page page; Il(p!l<Xz#
om%L>zfB
privateList users; );T0n
C^ngdba\
/* ,|hM`<"?
* (non-Javadoc) ,lK=m~
* z3!j>X_w
* @see com.opensymphony.xwork.Action#execute() U ObI&*2
*/ VwfeaDJw
publicString execute()throwsException{ ^):m^w.
Result result = userService.listUser(page); $hexJzX
page = result.getPage(); ~B!O
X
users = result.getContent(); 9kmEg$WM
return SUCCESS; r0ml|PX
} FEqs4<}E
*a_U2}N
/** z%xWP&3%"
* @return Returns the page. @Qw~z0PE<l
*/ ^(<Ecdz(
public Page getPage(){ e~#;ux
return page; &R