Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Zoc0!84<z
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 0,8okAH
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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 wg]LVW}
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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 .eP.&
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分页支持类: qWKAM@
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java代码: $"&{aa
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package com.javaeye.common.util; ohGfp9H
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import java.util.List; k,F6Tx
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publicclass PaginationSupport { A6iq[b]
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publicfinalstaticint PAGESIZE = 30; D+7Rz_=
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privateint pageSize = PAGESIZE; Mzw X>3x
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privateList items; *``JamnSO
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privateint totalCount; m<qJcZk
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privateint[] indexes = newint[0]; ,$+V
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privateint startIndex = 0; Vr1<^Ib
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public PaginationSupport(List items, int ^4Ah_U
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totalCount){ f &wb
setPageSize(PAGESIZE); "{Eta
setTotalCount(totalCount); \<6CZ
setItems(items); usL*
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setStartIndex(0); f[^Aw(o
} 84 pFc;<
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public PaginationSupport(List items, int .JiziFJ@mj
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totalCount, int startIndex){ x`IEU*z#
setPageSize(PAGESIZE); %O;bAC_M
setTotalCount(totalCount); n`&U~s8w
setItems(items); x6ARzH\
setStartIndex(startIndex); 2q4<t:!
} PO7Lf#9]
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public PaginationSupport(List items, int =;&yd';k
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totalCount, int pageSize, int startIndex){ #7YY<)
xt}
setPageSize(pageSize); 5vZ^0yFQ
setTotalCount(totalCount); &;sP_ h
setItems(items); ce3YCflt
setStartIndex(startIndex); gH7|=W
} 5K?IDt7A]
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publicList getItems(){ Yv!a88+A8M
return items; E6gI,f/p0X
} ]Y8<`;8/
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publicvoid setItems(List items){ #@~+HC=
this.items = items; B[-v[K2
} *zL}&RUKM
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publicint getPageSize(){ `eCo~(Fy
return pageSize; 8- %TC\:
} sCb=5uI
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publicvoid setPageSize(int pageSize){ ~-J]W-n
this.pageSize = pageSize; >R!jB]5
} 1sdLDw_)p
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publicint getTotalCount(){ ><$d$(
return totalCount; in- HUG
} "#oHYz3D
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publicvoid setTotalCount(int totalCount){ YCM]VDx4u1
if(totalCount > 0){ #c?j\Y9nz
this.totalCount = totalCount; +sUFv)!4
int count = totalCount / ApV~(k)W
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pageSize; 4'A!; ]:
if(totalCount % pageSize > 0) 2=`o_<P'"
count++; 04l!:Tp,
indexes = newint[count]; *P2S6z2
for(int i = 0; i < count; i++){ ],a 5)kV
indexes = pageSize * TS9|a{j3!
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} nd1+"-,q
}else{ cH?B[S;]
this.totalCount = 0; 5ZK@`jkE
} c~uKsU
} 4f'V8|QM{
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publicint[] getIndexes(){ #[~pD:qqM
return indexes; Zk"eA'"\
} [^e%@TV>d
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publicvoid setIndexes(int[] indexes){ sN2p76KN
this.indexes = indexes; &NK,VB;
} S4Ww5G?.
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publicint getStartIndex(){ >kp?vK;'B
return startIndex; \GZM&Zd
} Ksj -zR;
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publicvoid setStartIndex(int startIndex){ E!l!OtFL
if(totalCount <= 0) ^o1*a&~J@
this.startIndex = 0; `_RTw5{
elseif(startIndex >= totalCount) -w_QJ_z_
this.startIndex = indexes Xudg2t)+K
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[indexes.length - 1]; _EMwm&!
elseif(startIndex < 0) $?<Z!*x
this.startIndex = 0; D \sWZ
else{ V(6Z3g
this.startIndex = indexes /1Q(b
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[startIndex / pageSize]; khrb-IY@
} 5$&%re!{Z
}
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publicint getNextIndex(){ fM63+9I)\
int nextIndex = getStartIndex() + K]0:?h;%Ld
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pageSize; ahOM CZF|
if(nextIndex >= totalCount) vUU9$x
return getStartIndex(); *q".-u!D[
else <|+Ex
return nextIndex; $yYO_ZBiy
} db6b-Y{
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publicint getPreviousIndex(){ fb8g7H|
int previousIndex = getStartIndex() - uv(Sdiir8
G<f@#[$'
pageSize; 5Z\#0":e
if(previousIndex < 0) ws|;`
return0; L>%o[tS
else e5B Qr$j
return previousIndex; ~ga`\%J
} TXk?#G\o
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} pDcjwlA%
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抽象业务类 "zRoU$X
java代码: %.
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/** yo)%J
* Created on 2005-7-12 ;@Z#b8aM}
*/ (B_\TdQ
package com.javaeye.common.business; "xHg qgFyO
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import java.io.Serializable; .!,z:l$Kh
import java.util.List; (egzH?
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import org.hibernate.Criteria; !@'6)/
import org.hibernate.HibernateException; Mt5PaTjj
import org.hibernate.Session; *"n vX2iz
import org.hibernate.criterion.DetachedCriteria; okv 1K
import org.hibernate.criterion.Projections; C{DvD'^
import Dzs[GAQ]
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org.springframework.orm.hibernate3.HibernateCallback; \y)
import J@X'PG<
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org.springframework.orm.hibernate3.support.HibernateDaoS $8[r9L!
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upport; UE ,t8j
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import com.javaeye.common.util.PaginationSupport; <l9-;2L4
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public abstract class AbstractManager extends +g]yA3
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HibernateDaoSupport { fUQ6Z,9
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privateboolean cacheQueries = false; ehG/zVgn
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privateString queryCacheRegion; !M]\I &
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publicvoid setCacheQueries(boolean i21Gw41p:
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cacheQueries){ qfz 8jY]
this.cacheQueries = cacheQueries; xD[Gq%
} /iV}HV0
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publicvoid setQueryCacheRegion(String z;wELz1L{
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queryCacheRegion){ q)vplV1A
this.queryCacheRegion = sx51X^d
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queryCacheRegion; L^4-5`gj
} $N=N(^
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publicvoid save(finalObject entity){ Ox'/`Mppw
getHibernateTemplate().save(entity); >P $;79<
} /<8N\_wh
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publicvoid persist(finalObject entity){ m[@Vf9
getHibernateTemplate().save(entity); adi[-L#
} 9>rPe1iv
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publicvoid update(finalObject entity){ DHT&,=
getHibernateTemplate().update(entity); TdGnf
} BQ2wnGc
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publicvoid delete(finalObject entity){ ,b;{emX h
getHibernateTemplate().delete(entity); _#}n~}d
} PF7&p~O(Z
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publicObject load(finalClass entity, 4bJZmUb
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finalSerializable id){ V{&rQ@{W
return getHibernateTemplate().load `TPOCxM Mo
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(entity, id); 9{8GP
} $gM8{.!
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publicObject get(finalClass entity, ZzBQe
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finalSerializable id){ (q7
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return getHibernateTemplate().get \7
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(entity, id); aCxE5$~$
} LtKI3ou
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publicList findAll(finalClass entity){ NwR}yb6
return getHibernateTemplate().find("from Z@%HvB7
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" + entity.getName()); eDZ8w
} 0W()lQ
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publicList findByNamedQuery(finalString rJInj>|{=
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namedQuery){ z>06hBv(?Y
return getHibernateTemplate U"4?9.
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().findByNamedQuery(namedQuery); ~|AwN [
} r]Ff{la5
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publicList findByNamedQuery(finalString query, #vqo -y7@
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finalObject parameter){ $VQtwuYt
return getHibernateTemplate =FT98H2*|
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().findByNamedQuery(query, parameter); VCcr3Dx()F
} *I0-O*Xr
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publicList findByNamedQuery(finalString query, oejfU;+$
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finalObject[] parameters){ 5 VA(tzmCt
return getHibernateTemplate q0bHB_|wL
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().findByNamedQuery(query, parameters); <x),,a=X
} :g\rQazxO
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publicList find(finalString query){ ')$NfarQ.
return getHibernateTemplate().find lw(e3j
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(query); PSmfiaThwo
} [|3>MZ2/
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publicList find(finalString query, finalObject KYxBVgJ
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parameter){ 9r2IuS0
return getHibernateTemplate().find $.489x+'Z
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(query, parameter); <p?&udqD
} X}6#II
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public PaginationSupport findPageByCriteria V8~jf-\$b
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(final DetachedCriteria detachedCriteria){ STA4 p6
return findPageByCriteria ='E$-_
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ij'NC C
} 47T}0q,
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public PaginationSupport findPageByCriteria ._96*r=o
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(final DetachedCriteria detachedCriteria, finalint [&qA\
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startIndex){ sF+=KH
return findPageByCriteria #DkD!dW(l
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&
(detachedCriteria, PaginationSupport.PAGESIZE, H2-28XGc
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startIndex); 3v!~ cC~cI
} (,xZGa
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public PaginationSupport findPageByCriteria qUF1XJZ}z
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(final DetachedCriteria detachedCriteria, finalint !z
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pageSize, efuK
finalint startIndex){ kDz>r#%
return(PaginationSupport) wn11\j&
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getHibernateTemplate().execute(new HibernateCallback(){ 7>
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publicObject doInHibernate K$REZe
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(Session session)throws HibernateException { y/@iT8$rp
Criteria criteria = zG
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detachedCriteria.getExecutableCriteria(session); 7nHTlI1b
int totalCount = g9my=gY
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((Integer) criteria.setProjection(Projections.rowCount G7* h{nE
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()).uniqueResult()).intValue(); !@
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criteria.setProjection nD,{3B#
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(null); (w2=
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List items = '?Iif#Z1
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criteria.setFirstResult(startIndex).setMaxResults >AI<60/<
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(pageSize).list(); ad`_>lA4Lp
PaginationSupport ps = Pcu|k/tk
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new PaginationSupport(items, totalCount, pageSize, s([Wn)I
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startIndex); )8{6+{5lu
return ps; j:1uP^.
} =`I?mn&
}, true); 3,.%
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} -0,4egj3
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public List findAllByCriteria(final 8kW /DcLE
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DetachedCriteria detachedCriteria){ O=jN&<rb
return(List) getHibernateTemplate DPJh5d
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().execute(new HibernateCallback(){ 3^G96]E
publicObject doInHibernate mT_GrIl[
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(Session session)throws HibernateException { E:VGji7s
Criteria criteria = <uF [,
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detachedCriteria.getExecutableCriteria(session); pX<a2FP
return criteria.list(); hr U :Wr
} X_70]^XL
}, true); mPmB6q%)]
} \].J-^=
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public int getCountByCriteria(final u+% tPe
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DetachedCriteria detachedCriteria){ =wA5P@
Integer count = (Integer) Rk<%r k
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getHibernateTemplate().execute(new HibernateCallback(){ EE%s<_k`
publicObject doInHibernate M g!ra"
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(Session session)throws HibernateException { If}lJ6jZ
Criteria criteria = ;1LG&h,K
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detachedCriteria.getExecutableCriteria(session); !.+"4TF
return gGKKs&n7
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criteria.setProjection(Projections.rowCount w6EI{
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()).uniqueResult(); NdQ%:OKC
} v>WB FvyD
}, true); YIDg'a+z
return count.intValue(); cjg=nTsBA
} dp^N_9$cdO
} v"k4ATWP
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用户在web层构造查询条件detachedCriteria,和可选的 uJPH~mdW
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 9U10d&M(
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PaginationSupport的实例ps。 9N}W(>
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ps.getItems()得到已分页好的结果集 l @A"U)A(
ps.getIndexes()得到分页索引的数组 nO@+s
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ps.getTotalCount()得到总结果数 kukaim>K
ps.getStartIndex()当前分页索引 sfC@*Y2XT
ps.getNextIndex()下一页索引 ;Prg'R[o;
ps.getPreviousIndex()上一页索引 2k3 z'RLG
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ' PL_~
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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 +UaO<L
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一下代码重构了。 t~~r-V":
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我把原本我的做法也提供出来供大家讨论吧: .jum "va%
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首先,为了实现分页查询,我封装了一个Page类: QX/]gX
java代码: 3YRBI|XO
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/*Created on 2005-4-14*/ y7;
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package org.flyware.util.page; Heohe|an
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/** g)N54WV
* @author Joa (lb`#TTGx
* &U0WkW
*/
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publicclass Page { 6)+9G_
&"O_wd[+:
/** imply if the page has previous page */
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privateboolean hasPrePage; Znq(R8BMW
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/** imply if the page has next page */ iDR6?f P
privateboolean hasNextPage; I tgH>L'
Qf~| S9,
/** the number of every page */ ;y,NC2Xj
privateint everyPage; Qasr:p+
ujNt(7Cz
/** the total page number */ vF+YgQ1H
privateint totalPage; ,@,LD u
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/** the number of current page */ }*ODM6
privateint currentPage; Z
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/** the begin index of the records by the current ?PYNE
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query */ r"1A`89
privateint beginIndex; c_[ JjG^?P
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/** The default constructor */ M;> ha,x
public Page(){ |/2LWc?
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} f!^)!~
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/** construct the page by everyPage lWIv(%/@
* @param everyPage @#1cx
* */ I@+lFG
public Page(int everyPage){ ,$o-C&nC
this.everyPage = everyPage; _4~k3%w\`l
} gnYnL8l`J
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/** The whole constructor */ \S'cWB
public Page(boolean hasPrePage, boolean hasNextPage, oNrEIgaA(+
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int everyPage, int totalPage, *(>Jd|C
int currentPage, int beginIndex){ '>"`)-
this.hasPrePage = hasPrePage; enWF7`
this.hasNextPage = hasNextPage; _y|[Z;
this.everyPage = everyPage; iczs8gj*
this.totalPage = totalPage; Ml8E50t>;
this.currentPage = currentPage; W6hNJb
this.beginIndex = beginIndex; pFS
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} Z<w,UvJa
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/** 'o7R/`4KR
* @return `9]P/J^
* Returns the beginIndex. 'et(:}i
*/ q`h7H][(A
publicint getBeginIndex(){ R
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return beginIndex; NEZH<#
} I4A;
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/** 1w(<0Be
* @param beginIndex |>M-+@gj
* The beginIndex to set. ;CLR{t(N#V
*/ ngtuYASc
publicvoid setBeginIndex(int beginIndex){ t- !h
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this.beginIndex = beginIndex; p<<6}3~
} iJ5e1R8tN
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/** x|&[hFXD
* @return ux)< &p.
* Returns the currentPage. f|;HS!$
*/ %{7$\|;J'
publicint getCurrentPage(){ QxP` f KC8
return currentPage; E
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} &;'w8_K"^
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/** 8/Lu'rI
* @param currentPage ajf_)G5X P
* The currentPage to set. [^cs~
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*/ ")fOup@ ^a
publicvoid setCurrentPage(int currentPage){ ?+5"
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this.currentPage = currentPage; V6A5(-%`y
} 4;B=Qoxe
/5Gnb.zN)
/** 1uK)1%vK
* @return H57jBD
* Returns the everyPage. l6r%nHP@
*/ [N'r3
publicint getEveryPage(){ d#x8O4S%i2
return everyPage; nhB^Xr=
} 37.)@
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/** j 8~Gv=(h
* @param everyPage Y}eZPG.h
* The everyPage to set. ;igEIGR
*/ 11nO<WH
publicvoid setEveryPage(int everyPage){ C@l +\M(
this.everyPage = everyPage; Zw3hp,P]
} RlG'|xaT
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/** bcGn8
* @return Y/QK+UMW*
* Returns the hasNextPage.
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*/ V>~*]N^f
publicboolean getHasNextPage(){ q>Dr)x)
return hasNextPage; TXY
} AX!Md:s
/3xFd)|Ds
/** 2gK p\!
* @param hasNextPage BV_a-\Sa=
* The hasNextPage to set. #d7)$ub
*/ zIX}[l4EW~
publicvoid setHasNextPage(boolean hasNextPage){ 8'
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this.hasNextPage = hasNextPage; S^_JC
} x`j_d:C~G
AmUe0CQ:k'
/** K6PC&+x
* @return ^MF=,U'8
* Returns the hasPrePage. X.r!q1_c
*/ +'{:zN5m
publicboolean getHasPrePage(){ 3RY|l?n>
return hasPrePage; J:M<9W
} 7~Xu71^3s
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/** O V0cr
* @param hasPrePage dNS9<8JX
* The hasPrePage to set. R[2[[M
*/ Au\=ypK
publicvoid setHasPrePage(boolean hasPrePage){ {d{WMq$
this.hasPrePage = hasPrePage; kC,DW%Ls
} 1{Sx V
d@`-!"
/** qrORP3D@
* @return Returns the totalPage. }VJ hw*s
* }&'yt97+
*/ 8k*k
publicint getTotalPage(){ Tk2&{S "
return totalPage; '<U[;H9\
} !E(J
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/** v@<lEG#$"|
* @param totalPage Y
}g6IK}
* The totalPage to set. P89Dg/P
*/ b_"V%<I
publicvoid setTotalPage(int totalPage){ |<5J
this.totalPage = totalPage; ~T{d9yNW1
} UVvt&=+4
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} 1&x0+~G
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 !'UsC6Y4
xf3/<x!B
个PageUtil,负责对Page对象进行构造: jDkc~Wwa
java代码: vzgudxG'z
pQ6t]DJ4
U7Sl@-#|
/*Created on 2005-4-14*/ %.r5E2'
package org.flyware.util.page; DrYoC7
O,z%7><
import org.apache.commons.logging.Log; 1tK6lrhj
import org.apache.commons.logging.LogFactory; d#$i/&gE
FCw
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/** 2* cKFv{
* @author Joa FnU{C= P
* I "+|cFq.
*/ 62KW
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publicclass PageUtil { I$sm5oL
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privatestaticfinal Log logger = LogFactory.getLog G5Dji_ |
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(PageUtil.class); 7dL=E"WL
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/** W(3~F2
* Use the origin page to create a new page e?'k[ES^
* @param page .LVOaxT
* @param totalRecords > & lg
* @return %#;(]7Zq
*/ " kJWWR
publicstatic Page createPage(Page page, int `5aypJf1
fn"jYSy
totalRecords){ ~O3uje_
return createPage(page.getEveryPage(), A_$Mt~qKi^
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page.getCurrentPage(), totalRecords); "{1}
} fCo2".Tk
r E*u
/** X<bj2 w
* the basic page utils not including exception nCmrt*&}
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handler Ns] 9-D
* @param everyPage 3t}o0Ai9
* @param currentPage >w2WyYJYH
* @param totalRecords \<+47+
* @return page 29E@e]Y,`
*/ T<~[vjA
publicstatic Page createPage(int everyPage, int iZqFVr&JF
o+WrIAR
currentPage, int totalRecords){ .A f)y_
everyPage = getEveryPage(everyPage); ${H&Q*
currentPage = getCurrentPage(currentPage); (~yJce
int beginIndex = getBeginIndex(everyPage, Bd]DhPhJ
C=f(NpyD6
currentPage); NNrZb?
int totalPage = getTotalPage(everyPage, x@(f^P
pt;Sk?-1
totalRecords); Gb)iB
boolean hasNextPage = hasNextPage(currentPage, ;eSf4_~
761"S@tf$}
totalPage); )ejqE6'[
boolean hasPrePage = hasPrePage(currentPage); r}M4()9L
9'r3L)[
returnnew Page(hasPrePage, hasNextPage, $ }bC$?^
everyPage, totalPage, _|#|mb4Fe
currentPage, \:^n-D*fX
aNEy1-/(\
beginIndex); nylIP */
} _ r)hr7
wAwH8x LU
privatestaticint getEveryPage(int everyPage){ i3!$M/_]
return everyPage == 0 ? 10 : everyPage; ?At-
} m<HjL
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privatestaticint getCurrentPage(int currentPage){ &K*_/Q
'\
return currentPage == 0 ? 1 : currentPage; ATkqzE`;
} #6Ph"\G/
%R5MAs&-5
privatestaticint getBeginIndex(int everyPage, int -]MP,P%
tm#y`1-
currentPage){ JS.'v7
return(currentPage - 1) * everyPage; 0-O.*Q^
} 2xxwQwg8
X-WvKH(=w
privatestaticint getTotalPage(int everyPage, int fmyS#
6"
dfd%A"
I
totalRecords){ B{u.Yc:
int totalPage = 0; F?4'>ZW
*qOCo_=P8
if(totalRecords % everyPage == 0) >R0j<:p :
totalPage = totalRecords / everyPage; ?(hQZR
0e
else f
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totalPage = totalRecords / everyPage + 1 ; I>zn$d*0
h^X.e[
return totalPage; l3$?eGGM
} p;01a
t`D@bzLC%
privatestaticboolean hasPrePage(int currentPage){ f}uCiV!?v
return currentPage == 1 ? false : true; Bnc
} <GR: 5pJ%
r+yLK(<zp
privatestaticboolean hasNextPage(int currentPage, .Cd$=v6
HC}C_Q5c91
int totalPage){ b%$C!Tq'
return currentPage == totalPage || totalPage == |"*:ZSj
No+zw% l0E
0 ? false : true; $h
f\ #'J
} Nd)o1{I
?*dx=UI
~hX'FV
} ~Q]M_,`M
cK/odOi
>QPS0Vx[
\'b-;exH
c9k,Dc
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。 OOwJ3I >]>
q+Q)IVaU81
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 ,g.=vQm:?
h2snGN/{Hb
做法如下: t)+dW~g
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 W%:zvqg
v
f>PU# D@B
的信息,和一个结果集List: 7 {<lH%Tn
java代码: ]d(}b>gR~(
$SgD|
9
p.olXP
/*Created on 2005-6-13*/ :.^rWCL2
package com.adt.bo; 2%H(a)
#$QY[rf=6
import java.util.List; ttRH[[E(
Fb-TCq1y#
import org.flyware.util.page.Page; >iV(8EgBS
IA!Kpg
W
/** EeJ]>
1
* @author Joa lvffQ_t
*/ =Q/i<u
publicclass Result { =jh:0Q<43+
upKrr
private Page page; #nz$RJsX
3~'F^=T.Y
private List content; XCoOs<O:@
&GAx*.L
/** aKZD4;
* The default constructor 4[wP$
*/ :r=_\?
public Result(){ 'Mtu-\
super(); f{oWd]eAhb
} 9NAlgET
>i<-rO>kN
/** RPQ)0.O7
* The constructor using fields mYvm_t9
* ?i"FdpW
* @param page pj6Cvq4bD
* @param content ~E~J*R Ze
*/ ^DOcw@Z6HC
public Result(Page page, List content){ FW,D\51pTP
this.page = page; Y@eUvz
this.content = content; 7\lb+^$
} cCs:z
WBIS
/** 4 vphLAm
* @return Returns the content. 4{pa`o3
*/ wr(?L7
$+
publicList getContent(){ |Rc#Q<Vh|
return content; Tc:`TE=2
} AJmzg
5[k35c{
/** \;<Y/sg
* @return Returns the page. DSp@
*/ >%,tyJ~
public Page getPage(){ W#Z]mt B
return page; tK*f8X+q
} ^=j$~*(LmX
lVHJ}(<'p
/** WP9=@X Z
* @param content :C5N(x
* The content to set. +Gko[<
*/ 4(]k=c1<
public void setContent(List content){ @U5o;X!qU
this.content = content; &[uGfm+@
} CDhk!O..
5o*x?P!$
/** %qMk&1
* @param page iuEdm:pW
* The page to set. \kx9V|A'
*/ =v8q
publicvoid setPage(Page page){ t!tBN
this.page = page; ;uy/Vc5,Y
} -|5&3HVz
} J$oJ
ge|}'QKow
4kiu*T
eJ'ojc3
jiat5
2. 编写业务逻辑接口,并实现它(UserManager, d
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=z+zg^wsT
UserManagerImpl) OB%y'mo7]
java代码: 'Tn$lh
]So%/rOvX
Qa=;Elp:[
/*Created on 2005-7-15*/ })Jp5vv
package com.adt.service; !VW#hc\A5
:n=+$Dq
import net.sf.hibernate.HibernateException; Tym!7H2
:
SNp"|
import org.flyware.util.page.Page; w[iQndu
WG,{:|!E
import com.adt.bo.Result; IaB
A 2
#X+)
/** 6m9Z5:xG
* @author Joa B!Y;VdX
*/ g?ft;kR6S
publicinterface UserManager { uv$y"1'g
>}iYZ[ V
public Result listUser(Page page)throws 51A>eU|
j<[<qU:
HibernateException; d 9|u~3
PF~&!~S>W
} 4D8q Gti
f`Nu]#i
{,m!%FDL
L_(|5#IDw
J<2N~$
java代码: ]du pU"VV
"-9YvB#
.._wTOSq
/*Created on 2005-7-15*/ B*{CcQ<5
package com.adt.service.impl; KQk;:1hW
$ _zdjzT
import java.util.List; wS4zAu
F=cO=5Iz
import net.sf.hibernate.HibernateException; g#e"BBm=A
IzG7!K
import org.flyware.util.page.Page; i<l)To -
import org.flyware.util.page.PageUtil; g$ h!:wW
J;qH w[6
import com.adt.bo.Result; 0F"xU1z,
import com.adt.dao.UserDAO; MDRSI g
import com.adt.exception.ObjectNotFoundException; z~F!zigNAc
import com.adt.service.UserManager; qhogcAvE
VGSe<6Hh
/** G 2mv6xK'
* @author Joa a 3HS!/
*/ XG0,@Ly
publicclass UserManagerImpl implements UserManager { 'vXrA
7w9) ^
private UserDAO userDAO; b3Do{1BV
(t <Um
Vd
/** 8u>E(Vmpu
* @param userDAO The userDAO to set. nD!^0?
*/ ZEB1()GB
publicvoid setUserDAO(UserDAO userDAO){ IgVxWh#
this.userDAO = userDAO; ^OUkFH;dG?
} Vry#
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/* (non-Javadoc) R{.ku!w
* @see com.adt.service.UserManager#listUser r8mE
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(org.flyware.util.page.Page) rVkHo*Q
*/ kWWb<WRW:
public Result listUser(Page page)throws hI"I#(*jA%
s3q65%D
HibernateException, ObjectNotFoundException { _:{XL c
int totalRecords = userDAO.getUserCount(); N-suBRnW
if(totalRecords == 0) -IPc;`<
throw new ObjectNotFoundException 2rA`y8g(L
h4V.$e<T&
("userNotExist"); c|E
page = PageUtil.createPage(page, totalRecords); k1X <jC]P
List users = userDAO.getUserByPage(page); )+{'p0
returnnew Result(page, users); C; ! )<(Vw
} |XeuqZa
zdr?1=
} zD?<m
J`
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JIK;/1
&D/_@\ 0
yHCBf)N7\
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 /7*u!CNm
Tmq:,.^}
询,接下来编写UserDAO的代码: BONM:(1
3. UserDAO 和 UserDAOImpl: 55Jk "V#8
java代码: Q|:\
mgS%YG
@n<WM@|l
/*Created on 2005-7-15*/ B;^7Yu0,
package com.adt.dao; oSxHTbp?
.a$][Jny
import java.util.List; Jyvc(~x
y>|7'M*+
import org.flyware.util.page.Page; &}rh+z
r3#H]c
import net.sf.hibernate.HibernateException; VaH#~!
Fe:0nr9;
/** MSw/_{
* @author Joa 0LxA+
*/ *&LVn)@[`
publicinterface UserDAO extends BaseDAO { Up`zVN59.
]U]{5AA6
publicList getUserByName(String name)throws gg5`\}
i4AmNRs
HibernateException; C5F}*]E[y
hb`(d_= 7F
publicint getUserCount()throws HibernateException; U1B5gjN
a Z
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publicList getUserByPage(Page page)throws IS"UBJ6p
'H:lR1(,
HibernateException; iz>a0~(K
!<@Zf4m
} IeE+h-3p
A-uEZj_RD=
W&)OiZN
t[%9z6t
DqbN=[!X~n
java代码: [K,&s8N5
6dV92:
Wk`G+VR+
/*Created on 2005-7-15*/ >AV?g8B;
package com.adt.dao.impl; -49OE*uF
B$aboL2
import java.util.List; UEt#;e
x-Yt@}6mvl
import org.flyware.util.page.Page; Ust>%~<
WnU"&XZ
import net.sf.hibernate.HibernateException; FX 0^I 0
import net.sf.hibernate.Query;
n~k;9`
(yn!~El3
import com.adt.dao.UserDAO; L3'o2@$
>(p "!
/** ~%m-}Sxc
* @author Joa 2 ES .)pQ
*/ -TSn_XE
public class UserDAOImpl extends BaseDAOHibernateImpl >cQ*qXI0
qbpvTTF
implements UserDAO { O]90F
USfOc
/* (non-Javadoc) Z'hW;^e%_z
* @see com.adt.dao.UserDAO#getUserByName BB>3Kj:|
e=QnGT*b5
(java.lang.String) /\(0@To
*/ mq do@
publicList getUserByName(String name)throws tNoo3&
/EA4-#uw
HibernateException { =&< s*-l[
String querySentence = "FROM user in class
&CG3_s<2
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com.adt.po.User WHERE user.name=:name"; GjfY
Query query = getSession().createQuery ?&j[Rj0pH
JstX# z
(querySentence); 6uOR0L
query.setParameter("name", name); 0'% R@|
return query.list(); [_#9PH33
} O\-cLI<h2
48Z{wV,
/* (non-Javadoc) kbOdg:
* @see com.adt.dao.UserDAO#getUserCount() LEKN%2
*/ 8!'#B^
publicint getUserCount()throws HibernateException { ;a*i*{\Rm
int count = 0; T1LtO O
String querySentence = "SELECT count(*) FROM @I_A\ U{
J#!:Z8b
user in class com.adt.po.User"; eOE7A'X
Query query = getSession().createQuery P
BpjE}[Q
`[2nxP>w`
(querySentence); H'P1EZtq
count = ((Integer)query.iterate().next z<hy#BIjnd
[}N?'foLb
()).intValue(); w%g@X6
return count; Q_x/e|sd
} ke!)C[^7z
,g;~:
/* (non-Javadoc) <U (gjX
* @see com.adt.dao.UserDAO#getUserByPage +MIDq{B
3W5|Y@0
(org.flyware.util.page.Page) 0bVtku K;G
*/ FDkRfh K
publicList getUserByPage(Page page)throws nxA Y]Q
Z;P[)q
HibernateException { /#GX4&z
String querySentence = "FROM user in class JnlM0jc]`
&>ii2% 4
com.adt.po.User"; !LVWggk1
Query query = getSession().createQuery P*BA
e%afK@c
(querySentence); tK`sVsm>
query.setFirstResult(page.getBeginIndex()) XTUxMdN
.setMaxResults(page.getEveryPage()); m>yk4@a
return query.list(); y4t M0h
} G!C2[:[g
:MV]OLRM
} W7c(]
tg.
hCD0Zel
hHm&u^xY
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h7)^$Hd
至此,一个完整的分页程序完成。前台的只需要调用 .DMeWi
R#"kh/M
userManager.listUser(page)即可得到一个Page对象和结果集对象 s7A{<>:
k"uqso/
的综合体,而传入的参数page对象则可以由前台传入,如果用 C7dy{:y`
]8NNxaE3 (
webwork,甚至可以直接在配置文件中指定。 !k)}p_e
;XMbjWc
下面给出一个webwork调用示例: Zrr3='^s
java代码: mqrP0/sN
Q.*qU,4);
MRwls@z=
/*Created on 2005-6-17*/ O5CIK}A
package com.adt.action.user; mnzamp
Oz#$x
import java.util.List; iW(HOsA
sU^2I v\%
import org.apache.commons.logging.Log; M`*B/Fh2
import org.apache.commons.logging.LogFactory; KdHR.;*
import org.flyware.util.page.Page; 8 P.t
17I{_C
import com.adt.bo.Result; @Y 1iEL%\y
import com.adt.service.UserService; R
rs?I,NV
import com.opensymphony.xwork.Action; cKEf- &~
B.-5$4*s
/** 9<I@}w
* @author Joa >9'G>~P~I=
*/ ,A[40SZA
publicclass ListUser implementsAction{ iNUisl
q(M[ij
privatestaticfinal Log logger = LogFactory.getLog .h~M&d!
qAUqlSP5
(ListUser.class); \K.i8f,
2f9~:.NgF
private UserService userService; 'S@%
iA3d[%tBb
private Page page; j0B, \A
yv=LT~
privateList users; DmEmv/N=
&W:Wv,3
/* c9/w-u~j
* (non-Javadoc) *v)JX _
* VT96ph
* @see com.opensymphony.xwork.Action#execute() ;{
u{FL
*/ QU|{(c
publicString execute()throwsException{ R"Nvnpm
Result result = userService.listUser(page); S5*wUd*p#
page = result.getPage(); .^>[@w3
users = result.getContent(); dd>|1'-]
return SUCCESS; :{pvA;f
} []/=!?5B
y8HLrBTza
/** {";5n7<<)
* @return Returns the page. wv>Pn0cO
*/ }jBr[S5
public Page getPage(){ ol^V@3[<
return page;
.'mmn5E
} "%dWBvuO
8+{WH/}y8
/** O6LZ<}oUR
* @return Returns the users. &&4av*\I
*/ zYO+;;*@
publicList getUsers(){ E]WammX c
return users; N3g[,BE
} _m;0%]+
EKZ40z`
/** ?vPw I
* @param page EgM.wQHR]
* The page to set. +Gqh
*/ o\vIYQ
publicvoid setPage(Page page){ U~-Z`_@^-
this.page = page; rQg7r>%Q
} <&\HXAOd
.\M@oF
/** 7D\#1h
* @param users Rcs7 'q5
* The users to set. m663%b(5>
*/ I1^0RB{~
publicvoid setUsers(List users){ )[yM4QFl
this.users = users; dFD0l?0N
} Iz,a
Hrq
|C?<!6.QmV
/** jo{[*]Oa
* @param userService y5B4t6M(
* The userService to set. VJ;n0*/
*/ mj=$[y(
publicvoid setUserService(UserService userService){ | V Ps5
this.userService = userService; 2#~5[PtP^
} Z2~;u[0a[
} He}qgE>Us
LL|$M;S
%myg67u
4]0|fi3}>
; S7
%
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, -twV?~f
5BR9f3}
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 tNg}:a|J
Ql&5fyW
么只需要: _Z z"`
java代码: e84[B.
d]6.$"\"p
5xX*68]%
<?xml version="1.0"?> \L}aTCvG
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork RhIRCN9
4<fKB&