Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ,&y_^-|d
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 e ?FQ6?
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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 0!oqP1
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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 iiF`2
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分页支持类: a,(nf1@5
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java代码: #%w+PL:*O
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package com.javaeye.common.util; (H"{r
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import java.util.List; yEk|(6+^
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publicclass PaginationSupport { B!&y>Z^$
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publicfinalstaticint PAGESIZE = 30; l(Dr@LB~
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privateint pageSize = PAGESIZE; <B>hvuCoH
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privateList items; UBJYs{zz
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privateint totalCount; ?XP4kjJ
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privateint[] indexes = newint[0]; -%|
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privateint startIndex = 0; 0U:X[2|)
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public PaginationSupport(List items, int pL!,1D!
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totalCount){ p(nO~I2E
setPageSize(PAGESIZE); TspX7<6r
setTotalCount(totalCount); JZ+6)R
setItems(items); w>8kBQ?b
setStartIndex(0); &-{%G=5~e%
} m5&Ht (I%n
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public PaginationSupport(List items, int > ;#Y0
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totalCount, int startIndex){ S(nQ?;9,
setPageSize(PAGESIZE); 63J3NwFt
setTotalCount(totalCount); t- TUP>_
setItems(items); R)ZzRz|/
setStartIndex(startIndex); ZZZ`@pXm;
} Pksr9"Ah
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public PaginationSupport(List items, int
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l1|*(%p?X
totalCount, int pageSize, int startIndex){ q'a]DJ`
setPageSize(pageSize); U;TS7A3
setTotalCount(totalCount); |vm-(HY!
setItems(items); SvQ|SKE':
setStartIndex(startIndex); SjpCf8Z(
} {[`(o
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publicList getItems(){ !.^x^OK%y
return items; I\1"E y
} 6P}?+ Gc
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publicvoid setItems(List items){ r]&sXKDc
this.items = items; @*~yVV!5
} -s!J3DB
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publicint getPageSize(){ 0Ze&GK'Hf
return pageSize; 1LSJy*yY
} xb%Q[V_m
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publicvoid setPageSize(int pageSize){ B~k{f}
this.pageSize = pageSize; XR9kxTuk
} )B+o
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publicint getTotalCount(){ r7>FH!=:
return totalCount; -,YI>!
} DBHHJD/q
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publicvoid setTotalCount(int totalCount){ AzF*4x
if(totalCount > 0){ 74:( -vS
this.totalCount = totalCount; Te~jYkCd
int count = totalCount / <}A6 )=T
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pageSize; v;5-1
if(totalCount % pageSize > 0) Q]GS#n
count++; kjp~:Bg_(
indexes = newint[count]; Sz<:WY/(x
for(int i = 0; i < count; i++){ Gey-8
indexes = pageSize * _<jU! R
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i; ,r~^<m
} l3BN,HNv+
}else{ l3u+fE,;_
this.totalCount = 0; s.rQiD
} xzA!,75@U
} &&52ji<3
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publicint[] getIndexes(){ .sQV0jF {
return indexes; !`7evV:
} x1`(Z|RJ
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publicvoid setIndexes(int[] indexes){ Z.Z31yF:f
this.indexes = indexes; U';)]vB$
} [tSv{
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publicint getStartIndex(){ ewN|">WXQ
return startIndex; T"3LO[j+
} bv(+$YR
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publicvoid setStartIndex(int startIndex){ FZ<6 kk4
if(totalCount <= 0) ib
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this.startIndex = 0; BR?DW~7J j
elseif(startIndex >= totalCount) v(JjvN21
this.startIndex = indexes *y|w9rp
2?Ryk`2i)
[indexes.length - 1]; U?|A3;,xh
elseif(startIndex < 0) "k
this.startIndex = 0; ;nbEV2Y<
else{ e@vZg8Ie
this.startIndex = indexes |}e"6e%
uEr.LCAS
[startIndex / pageSize]; ~H?v L c;>
} #P z'-lo
} %La/E#
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publicint getNextIndex(){ SJO*g&duQ
int nextIndex = getStartIndex() + (QqeMG,Y
^/Yk*Ny
pageSize; ^t<L
if(nextIndex >= totalCount) psx_gv,
return getStartIndex(); UHi^7jQ
else P|?nx"c
return nextIndex; qFDy)4H)
} sA: /!9
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publicint getPreviousIndex(){ pp*MHM)x|q
int previousIndex = getStartIndex() - ? N]bFW"t|
u 1}dHMoX~
pageSize; X"g,QqDD
if(previousIndex < 0) S\sy^Kt~4:
return0; y|*4XF<b
else y,Bj,zw
return previousIndex; L{&1w
} gMq;
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cru
} I|Hcs.uW
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抽象业务类 gGA5xkA
java代码: 6rG7/
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/** l,A\]QDvl
* Created on 2005-7-12 e*(
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*/ =8p[ (<F=
package com.javaeye.common.business; "Ya;&F.'
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import java.io.Serializable; CnY dj~
import java.util.List; 4U)%JK.ta
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import org.hibernate.Criteria; T?u*ey~Tv
import org.hibernate.HibernateException; w8>bct3@
import org.hibernate.Session; {BA Z`I
import org.hibernate.criterion.DetachedCriteria; I|>IV
import org.hibernate.criterion.Projections; ci(BPnQ
import [vY)y\W{
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org.springframework.orm.hibernate3.HibernateCallback; l`0JL7
import ao2o!-?!t
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org.springframework.orm.hibernate3.support.HibernateDaoS T_)+l)
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upport; }!s$
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import com.javaeye.common.util.PaginationSupport; 55>+%@$,a
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public abstract class AbstractManager extends Pff-eT+~m
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HibernateDaoSupport { .fhfO @
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privateboolean cacheQueries = false; Dn~t _n
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privateString queryCacheRegion; ;4oKF7]
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publicvoid setCacheQueries(boolean t`\l+L
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cacheQueries){ 9@Z++J.^y
this.cacheQueries = cacheQueries; ?PB}2*R
} m Ub2U&6(
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publicvoid setQueryCacheRegion(String =E~SaT
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queryCacheRegion){ Pc~)4>X<
this.queryCacheRegion = /h&>tYVio
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queryCacheRegion; OW> >6zM
} jz&= 8
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publicvoid save(finalObject entity){ 1BzU-Ma
getHibernateTemplate().save(entity); WPu%{/[
} )[t3-'
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publicvoid persist(finalObject entity){ *q Ins/@
getHibernateTemplate().save(entity); *nUa0Zg4q6
} ju"j?2+F
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publicvoid update(finalObject entity){ a9nXh6
getHibernateTemplate().update(entity); 0R,Y[).U
} VD=F{|^
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publicvoid delete(finalObject entity){ jLul:*
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getHibernateTemplate().delete(entity); u/?;J1z:
} ~BI! l
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publicObject load(finalClass entity, -f(<2i
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finalSerializable id){ (W`=`]!
return getHibernateTemplate().load |qibO \_
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(entity, id); rk?G[C)2c
} n ZS*"O#L
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publicObject get(finalClass entity, y {Mh ?H
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finalSerializable id){ KH1/B_.\V
return getHibernateTemplate().get X@B,w_b
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(entity, id); !r0 z3^*N
} F8Z6Ss|v3
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publicList findAll(finalClass entity){ S#7.y~e\
return getHibernateTemplate().find("from SRk-3 :
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" + entity.getName()); akA C^:F
} |<7nf7 5c}
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publicList findByNamedQuery(finalString 4\8k~#
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namedQuery){ nHL(v
return getHibernateTemplate zd[cp@
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().findByNamedQuery(namedQuery); #1f8A5<
} gC S%J40r
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publicList findByNamedQuery(finalString query, 3sGe#s%
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finalObject parameter){ ~7=w,+
return getHibernateTemplate Wv)2dD2I
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().findByNamedQuery(query, parameter); `L}Irt}
} IqONDdep9
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publicList findByNamedQuery(finalString query, T k>N4yq
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finalObject[] parameters){ C0Ti9
return getHibernateTemplate ldm=uW
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().findByNamedQuery(query, parameters); !.k
} y3C$%yv0
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publicList find(finalString query){ 8/E?3a_g-
return getHibernateTemplate().find Fop"m/
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(query); l4Y}<j\;
} !~k-Sexh
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publicList find(finalString query, finalObject ^k?Ig.m
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parameter){ 2myHn/%C
return getHibernateTemplate().find F D6>[W
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(query, parameter); ^Q4m1?
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} )zVD!eG_9
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public PaginationSupport findPageByCriteria T|[o
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(final DetachedCriteria detachedCriteria){ iP JZ%
return findPageByCriteria 8[;U|SR"
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); fKAG+ t
} Iih~rWJ
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public PaginationSupport findPageByCriteria Lw.N3!e[
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(final DetachedCriteria detachedCriteria, finalint E8Wgm
8
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startIndex){ eESJk14
return findPageByCriteria -3c?Yaf"
PV%7m7=x
(detachedCriteria, PaginationSupport.PAGESIZE, z|SLH<~
n2H2G_-L[
startIndex); %8+'L4
} e&u HU8k*
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public PaginationSupport findPageByCriteria PF-
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(final DetachedCriteria detachedCriteria, finalint !g~xn2m$R
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pageSize, |nj%G<
finalint startIndex){ <H~ (iQ
return(PaginationSupport) E$rn^keM
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getHibernateTemplate().execute(new HibernateCallback(){ "sRR:wzQu
publicObject doInHibernate .yF7{/
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(Session session)throws HibernateException { 7@Qz
Criteria criteria = S-:l
60.
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detachedCriteria.getExecutableCriteria(session); R
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int totalCount = E7axINca
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((Integer) criteria.setProjection(Projections.rowCount ^r$P&}Z\b
@&d/}Mx"t
()).uniqueResult()).intValue(); Jh[fFg]
criteria.setProjection yHhBUpIo
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(null); [N925?--S
List items = 6kKIDEX
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criteria.setFirstResult(startIndex).setMaxResults 3%xj-7z
W
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(pageSize).list(); hM(|d@)
PaginationSupport ps = >+fet ,
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new PaginationSupport(items, totalCount, pageSize, ,?7URx*
(_E<?
startIndex); KaHjL&!
return ps; Y9 ,KOs
} vh+IhGi
}, true); `hL16S
} 5>JrTO5
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public List findAllByCriteria(final t8 #&bUX
}S$]MY,*
DetachedCriteria detachedCriteria){ !B(6
return(List) getHibernateTemplate m4|9p{E
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().execute(new HibernateCallback(){ uQ{ &x6.1
publicObject doInHibernate 0\Qqv7>
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(Session session)throws HibernateException { 5+'1 :Sa(i
Criteria criteria = Rg,pC.7;
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detachedCriteria.getExecutableCriteria(session); 'cT R<LVo
return criteria.list(); ]Z@-r
} ' Ky5|4
}, true); W)?B{\
} =\?KC)F*e
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public int getCountByCriteria(final ,)nO
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DetachedCriteria detachedCriteria){ Lu6!W
Integer count = (Integer) WeE>4>^
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getHibernateTemplate().execute(new HibernateCallback(){ c63DuHA*C
publicObject doInHibernate Y|g8xkI}XB
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(Session session)throws HibernateException { c
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Criteria criteria = /A4zR
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detachedCriteria.getExecutableCriteria(session); tD.md_E
return 5EIh5Y EU>
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criteria.setProjection(Projections.rowCount \L(~50{(
{?17Zth
()).uniqueResult(); :03w k)
} ^N _kiSr
}, true); 6+e@)[l.zc
return count.intValue(); E=3<F_3W
} YUat}-S
} ne4hR]:
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用户在web层构造查询条件detachedCriteria,和可选的
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 gh|TlvnA
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PaginationSupport的实例ps。 )Y+n4UL3NK
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ps.getItems()得到已分页好的结果集 [*Nuw_l
ps.getIndexes()得到分页索引的数组 VChNDHiH
ps.getTotalCount()得到总结果数 )"2)r{7:
ps.getStartIndex()当前分页索引 U@!e&QPn
ps.getNextIndex()下一页索引 +LCpE$H
ps.getPreviousIndex()上一页索引 nc!P
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Ly0^ L-~|
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 qI"Xh"
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bf|s=,D
一下代码重构了。 Stq&^S\x69
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我把原本我的做法也提供出来供大家讨论吧: 4!64S5(7t
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首先,为了实现分页查询,我封装了一个Page类: OaY.T
java代码: P3UU~w+s
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/*Created on 2005-4-14*/ t<wjS|4
package org.flyware.util.page; tAO,s ZW
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/** d
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* @author Joa DJvmwFx
* ]1hW/!
*/ "`qmeZ$rg
publicclass Page { uT:'Kkb!
:jlKj} 4A
/** imply if the page has previous page */ 3oc p4x`[
privateboolean hasPrePage; E1 IT>_
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/** imply if the page has next page */ ce@1#}*
privateboolean hasNextPage; }W^%5o87{
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/** the number of every page */ GdHFgxI
privateint everyPage; Is1P,`*!
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/** the total page number */ viB'ul7o
privateint totalPage; A?i
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Wu3or"lcw*
/** the number of current page */ g<pr(7jO
privateint currentPage; yNCd}
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/** the begin index of the records by the current 4&%0%
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query */ B;x5os
privateint beginIndex; ybNo`:8A;
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@+Ch2Lod
/** The default constructor */ {\zTE1X9
public Page(){ 3/_rbPr
pGz 5!d
} Rp.42v#ck
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/** construct the page by everyPage \#Md3!MG
* @param everyPage T_iX1blrgh
* */ kNq>{dNRx
public Page(int everyPage){ |H-%F?<{
this.everyPage = everyPage; a',6WugIP
} OlRtVp1
!r\u,l^
/** The whole constructor */ >TI/W~M
public Page(boolean hasPrePage, boolean hasNextPage, r@")MOGc
(;\"
K?
8Of.n7{
int everyPage, int totalPage, CjR!dh1w_
int currentPage, int beginIndex){ eX)'C>4W
this.hasPrePage = hasPrePage; u}I-#j)wap
this.hasNextPage = hasNextPage; O-P'Ff"}t
this.everyPage = everyPage; Td,2.YMQ
this.totalPage = totalPage; zF:
:?L~
this.currentPage = currentPage; M%&1j >d
this.beginIndex = beginIndex; +;r1AR1)x
} U]/iPG&_
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/** Me;XG?`
* @return /q1k)4?E
* Returns the beginIndex. YV%y
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*/ ~mBY_[_s=
publicint getBeginIndex(){ g[G+s4Nv
return beginIndex; n_~u!Ky_P
} "w7{,HP
5Z;iK(>IX
/** v']Tusmg
* @param beginIndex Ei>.eXUD5
* The beginIndex to set. 1S[4@rZ
*/ U:r^4,Mz*
publicvoid setBeginIndex(int beginIndex){ r+TvC{
this.beginIndex = beginIndex; aH/8&.JLi
} ;Mw<{X-
Ms<v81z5T
/** J:Mn5hdK=
* @return >c`r&W.t
* Returns the currentPage. h2jrO9
*/ M!i["($_
publicint getCurrentPage(){ M r-l
return currentPage; Vh ?5
} SfSWjq
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/** m@Hg:DY
* @param currentPage O0l1AX"
* The currentPage to set. hy&WG&qf
*/ i[Qq,MmC
publicvoid setCurrentPage(int currentPage){ / jLb{Ky
this.currentPage = currentPage; ]hMs:$}
} g3|k-
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/** E]w2
{%
* @return xiv8q/
* Returns the everyPage. Vp$<@Y
*/ /np05XhEa
publicint getEveryPage(){ G^ShN45
return everyPage; :3N6Ej
} VwN=AFk
Oj
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/** 1y3)ogL
* @param everyPage n\GN}?4
* The everyPage to set. x)R1aq
*/ y(<+=
publicvoid setEveryPage(int everyPage){ ]FNe&o1zX
this.everyPage = everyPage; $b U.6
} <=~*`eWV
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/** %)ri:Q q
* @return
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* Returns the hasNextPage. dvE~EZcS
*/ 42f\]R,
publicboolean getHasNextPage(){ TO&^%d
return hasNextPage; |F4)&xN\
} !_q=r[D\
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/** }0[<xo>K
* @param hasNextPage P^aNAa
* The hasNextPage to set. j];#=+
*/ EG8%X "p
publicvoid setHasNextPage(boolean hasNextPage){ yxtfyf|9 '
this.hasNextPage = hasNextPage; I!"/ I8Y
} !eHQe7_
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/** L)i6UAo
* @return B='(0Uxy-
* Returns the hasPrePage. }S"qU]>8a
*/ hbe";(
publicboolean getHasPrePage(){ _WGWU7h
return hasPrePage; vL#I+_ 2
} @.,Mn#
ba tXj]:
/** >u\'k+=
* @param hasPrePage \WqC^Di
* The hasPrePage to set. x"7PnN|~
*/ ki'<qa
publicvoid setHasPrePage(boolean hasPrePage){ = R n
this.hasPrePage = hasPrePage; RDU 'l^
} HBNX a
HXN. ,[
/** vA{DF{S4
* @return Returns the totalPage. }tW1\@
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* wE-y4V e
*/ g) ofAG2
publicint getTotalPage(){ SmS6B5j\R
return totalPage; l\"CHwN?Y
} ?e%u[ Q0
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/** 29nMm>P.e
* @param totalPage +W/{UddeKU
* The totalPage to set. TtrV
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*/ RA!8AS?
publicvoid setTotalPage(int totalPage){ 4av
this.totalPage = totalPage; ^jXKM!}-E
} `46|VQAx
S\ K[l/
} z%]3`_I
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qYPgn_
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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 &p+2Vz{
*'BI=*`
个PageUtil,负责对Page对象进行构造: pJ
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java代码: q&&uX-ez5W
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VVEJE$
/*Created on 2005-4-14*/ \'X-><1
package org.flyware.util.page; M<x><U#]A
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import org.apache.commons.logging.Log; |RBL5,t^
import org.apache.commons.logging.LogFactory; a# Uk:O!
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/** g2vt(Gf ;
* @author Joa mC$ te
* a
*bc#!e
*/ f*EDSJu\
publicclass PageUtil { K#N5S]2yb
-%Jm-^F I
privatestaticfinal Log logger = LogFactory.getLog 5! ]T%.rM
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(PageUtil.class); 8} X>u2t
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/** <J]N E|:
* Use the origin page to create a new page ,!^g8zO
* @param page MIu'OJ"z~
* @param totalRecords bWZ
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* @return _$mS=G(
*/ ]'vAeC6{
publicstatic Page createPage(Page page, int )"Wy/P
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totalRecords){ eH 9-GGr
return createPage(page.getEveryPage(), rc}=`D`
rm<`H(cT
page.getCurrentPage(), totalRecords); Kww+lgzS
} m[w~h\FS
:UfaMe5
/** V.!z9AQ
* the basic page utils not including exception ioslarw1J
xw*/8.Md6f
handler 0a+U >S#
* @param everyPage "VeNc,-nfQ
* @param currentPage B~3qEdoK5`
* @param totalRecords aSeh?2n8
* @return page HmV JkkksJ
*/ 1y7$"N8Xo
publicstatic Page createPage(int everyPage, int _Ry
@iVEnb.'
currentPage, int totalRecords){ ZO \bCrk
everyPage = getEveryPage(everyPage); <2\QY
currentPage = getCurrentPage(currentPage); 2~)q080jh
int beginIndex = getBeginIndex(everyPage, _2<k,Dl;RY
P!/:yWd
currentPage); UFE~6"t(
int totalPage = getTotalPage(everyPage, I^QB`%v5
%"3tGi:/
totalRecords); AVp"<Uv
boolean hasNextPage = hasNextPage(currentPage, ?o(Y\YJf
fM<g++X
totalPage); MENrP5AL
boolean hasPrePage = hasPrePage(currentPage); zENo2#{_N
/j:-GJb*!u
returnnew Page(hasPrePage, hasNextPage, ]r1Lr{7^S
everyPage, totalPage, Y2>*' nU
currentPage, k")3R}mX
)1&,khd/u
beginIndex); SU4~x0
} AH
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8=3$U+
privatestaticint getEveryPage(int everyPage){ rzKn5Z
return everyPage == 0 ? 10 : everyPage; a@-!,Hi
} e)4L}a
jAD{?/RB}
privatestaticint getCurrentPage(int currentPage){ =l$qwcfbo
return currentPage == 0 ? 1 : currentPage; (<yQA. M
} o &E2ds3
<-|g>
privatestaticint getBeginIndex(int everyPage, int j2:A@a6
i^/D_L.
currentPage){ .Tc?9X~4
return(currentPage - 1) * everyPage; }}v28"\TA
} g@S?5S.Av
cs)z!
privatestaticint getTotalPage(int everyPage, int h{Y#. j~aS
I\VC2U
totalRecords){ T( bFn?
int totalPage = 0; I=V]_Ik4N
RTYhgq
if(totalRecords % everyPage == 0) x;/%`gKn8
totalPage = totalRecords / everyPage; r)Iq47Uiw
else ?E7.x%n7X5
totalPage = totalRecords / everyPage + 1 ;
av!~B,
wEIAU
return totalPage; +|Qe/8Q
} !'%`g,,r
UyOoyyd.
privatestaticboolean hasPrePage(int currentPage){ $@L}/MO
return currentPage == 1 ? false : true; 9 Dx9alJR
} }!Xj{Eoc
xW'(]Z7_
privatestaticboolean hasNextPage(int currentPage, +tFl
4";[Xr{pW
int totalPage){ ,:/3'L
return currentPage == totalPage || totalPage == %D*yXNsY
3Y=?~!,Jk
0 ? false : true; q0QB[)AP
} "ZFK-jn/
lmr:PX
\YsYOFc|
} 6Vc&g
8Vqh1<
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v]BMET[w
)WazbT@
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。 XDq*nA8#5B
l050n9#9p
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 Kg;1%J>ee
*.Ceb%W7C
做法如下: T>s3s5Y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 JIU=^6^2'
R>.
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的信息,和一个结果集List: )~[hf,R5S
java代码: p'IF2e&z
"# BI"
-AxO1
qO
/*Created on 2005-6-13*/ [O(8izv
package com.adt.bo; ].<B:]:,
@I|gA
import java.util.List; j]5bs*G
v}\Nx[}
import org.flyware.util.page.Page; ?)B\0` %*'
[ !#<nY/C
/** GFBku^pi
* @author Joa Q#rj>+?
*/ 4>W ov
publicclass Result { eo&nAr
}Qm: g
private Page page; Ox1#}7`0>
R7d45Wl
private List content; ]\5?E }kd
r.b!3CoQ
/** \`M8Mu9~w
* The default constructor _}-Ed,.=
*/ !z]2+
public Result(){ \4OX]{
super(); y6nPs6kR
} ix]t>2r
.d>TU bR;
/** 7}e73
* The constructor using fields $.2#G"|
* 8%wu:;*]%
* @param page /2e&fxxD
* @param content lUd;u*A
*/ 0xYPK7a=L\
public Result(Page page, List content){ jRP9e
this.page = page; -r5JP[0kP
this.content = content; Xn
1V1sr
} Q5H!
^RQm
kq kj.#u
/** V>&WZY
* @return Returns the content. d}t7bgk'j
*/ k*3F7']8
publicList getContent(){ ~SRK}5E
return content; 09S LQVo
} ``Wf%~
|8m;}&r$
/** s8/y|HN^
* @return Returns the page. ;NHZD
*/ ;L458fYs
public Page getPage(){ T!*lTzNHm
return page; 6RLYpQ$+
} S3iXG
@
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/** /RzL,~]
* @param content ?2#MU
* The content to set. (93+b%^[
*/
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public void setContent(List content){ V6C*d:
this.content = content; =x/Ap1
} O:Ixy?b;Z
nM1F4G
/** `"/s," c:D
* @param page *+ql{\am4N
* The page to set. ?B"k9+%5ej
*/ ""JTU6]MS
publicvoid setPage(Page page){ 8i=c|k,GL.
this.page = page; >vP DF+ u
} *?a rEYc8
} Az}.Z'LJ
5mxYzu;#]
u._B7R&>
}j/($,
#MyR:V*a
2. 编写业务逻辑接口,并实现它(UserManager, ,u1Yn}
?W*{%my
UserManagerImpl) Nj<}t/e
java代码: +M"Fv9
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Cz%tk}2
/*Created on 2005-7-15*/ I0
78[3b
package com.adt.service; &?R2zfcM
kf8-#Q/B
import net.sf.hibernate.HibernateException;
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Z-fQ{&a{
import org.flyware.util.page.Page; c&{1Z&Y
xV_,R'l
import com.adt.bo.Result; f.%mp$~T
'Olp2g8=
/** UbD1h_b
* @author Joa =r3 %jWH6
*/ H6Mqy}4W
publicinterface UserManager { E,S[3 +
Li jisE
public Result listUser(Page page)throws QgZwU$`p0
mIK-a{?G
HibernateException; TzC'xWO
!\
IgTt,
} /A8ua=Kn
(aAv7kB&
J|9kWjOf+i
Uq:WW1=kh
-bN;nSgb
java代码: O T*C7=
Z r}5)ZR.
qgT~yDm
/*Created on 2005-7-15*/ CEwMPPYnD
package com.adt.service.impl; FUVoKX!#
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import java.util.List; 3C,G~)=
x
u?(@hUV.
import net.sf.hibernate.HibernateException; TY(B]Q_o
\{Qd
import org.flyware.util.page.Page; 3D"2yTM(
import org.flyware.util.page.PageUtil; RObo4
?s=O6D&
import com.adt.bo.Result; Vq'\`$_
import com.adt.dao.UserDAO; *Kpk1
import com.adt.exception.ObjectNotFoundException; 7,MDFO{n
import com.adt.service.UserManager; [g bYIwL.
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/** F;4*,Ap
* @author Joa o$*aAgS+
*/ gx-ib/_f1
publicclass UserManagerImpl implements UserManager { ,g.*Mx`-
'pCZx9*c
private UserDAO userDAO; |[/<[@\''
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/** :bh#,]'
* @param userDAO The userDAO to set. a.n;ika]-
*/ FeW}tKH
publicvoid setUserDAO(UserDAO userDAO){ @%(Vi!Cv"R
this.userDAO = userDAO; SdOa#U)
} E[:eMJR
zTgY=fuz
/* (non-Javadoc) j20/Q)=h
* @see com.adt.service.UserManager#listUser Lro[ |A
+-DF3(
(org.flyware.util.page.Page) OcA_m.
*/ |WiE`&?xP
public Result listUser(Page page)throws e-!6m#0
iKJ-$x_5
HibernateException, ObjectNotFoundException { kLsp0%2
int totalRecords = userDAO.getUserCount(); WH>= *\
if(totalRecords == 0) <G};`}$a
throw new ObjectNotFoundException U$*AV<{%
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iW,Q;
("userNotExist"); jGg,)~)Y
page = PageUtil.createPage(page, totalRecords); wzXIEWJ
List users = userDAO.getUserByPage(page); ?QDHEC62
returnnew Result(page, users); Dq [f
} F@8G,$
N('=qp9
} JPH! .@
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'|I8byiK
4YuJ -
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 'YKzs ;y$
)x!b{5'"7
询,接下来编写UserDAO的代码: Xkqq$A4
3. UserDAO 和 UserDAOImpl: 86*9GS?U(
java代码: PBeBI:
.tdaj6x
HT`k-}ho,
/*Created on 2005-7-15*/ CPW^pGT+i
package com.adt.dao; 2)~`.CD?L
AiP#wK;
import java.util.List; @
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L;7u0Yg
import org.flyware.util.page.Page; e(=() :4is
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import net.sf.hibernate.HibernateException; x%v[(*F#y
e3#0r
/** %E R"Udh
* @author Joa ,QeJ;U
*/ -> ^Ex`
publicinterface UserDAO extends BaseDAO { _Gu;= H,~&
w4nU86oZYl
publicList getUserByName(String name)throws Y>/T+ub
(-no`j
HibernateException; 5}3#l/
L">\c5ca
publicint getUserCount()throws HibernateException; rD\)ndPv
fT2F$U
publicList getUserByPage(Page page)throws x>cl$41!W
YE*%Y["
HibernateException; r|_@S[hZg
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} d-sT+4o}
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5%_aN_1?ef
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java代码: Sx0/Dm
hCOCX_
}@y(-7t
/*Created on 2005-7-15*/ oH,{'S@q
package com.adt.dao.impl; gTS}'w{
W ZT) LYA
import java.util.List; YYN'LF#j
4St-Q]Y _
import org.flyware.util.page.Page; BXb=NE
fTOGW`s^
import net.sf.hibernate.HibernateException; 7DKTd^^M
import net.sf.hibernate.Query; 68?>#o865
+SB>>
import com.adt.dao.UserDAO; :R-_EY$k6
%/4_|.8u
/** ]vflx^<?
* @author Joa xZ]QT3U+
*/ Yyr
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public class UserDAOImpl extends BaseDAOHibernateImpl k-N}tk/5
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implements UserDAO { ,Y4>$:#n/
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/* (non-Javadoc) d =p=eUd2
* @see com.adt.dao.UserDAO#getUserByName q'Nafa&a)
E!9(6G4
(java.lang.String) )H>?K0I
*/ ~n~j2OE
publicList getUserByName(String name)throws n *EGOS
!(F?Np Am
HibernateException { 9Tg
k=
String querySentence = "FROM user in class iG ,z3/~v
^@C/2RX!
com.adt.po.User WHERE user.name=:name"; aXyFpGdb9
Query query = getSession().createQuery A+MG?k>yg
WM;5/;bB
(querySentence); >B<#,G
query.setParameter("name", name); Dv*d$
return query.list(); @__m>8wn
} 9/`3=r@
9SBTeJ$RZ
/* (non-Javadoc) &qzy?/i8
* @see com.adt.dao.UserDAO#getUserCount() Y?qUO2
*/ @#p6C
publicint getUserCount()throws HibernateException { jL7r1pu5
int count = 0; D#D55X^6*
String querySentence = "SELECT count(*) FROM #P1U]@
^;9<7h[l
user in class com.adt.po.User"; %L|xmx!c
Query query = getSession().createQuery 6)PnzeYW
R/xT.EQ(N
(querySentence); js9^~:Tw
count = ((Integer)query.iterate().next PfsUe,*
I.'/!11>
()).intValue(); >WA'/Sl<A<
return count; m1e Sn |)7
} g%V#Z`*|
0R,.
/* (non-Javadoc) ["#H/L]3
* @see com.adt.dao.UserDAO#getUserByPage *10qP?0H
Om*(dK]zHQ
(org.flyware.util.page.Page) c*y*UG
*/ D4N(FZ0~
publicList getUserByPage(Page page)throws 73_=CP"t
.EReYZO
HibernateException { (hBph+
String querySentence = "FROM user in class o`Af6C;Q
id9 XwWV
com.adt.po.User"; >,QCKZH
Query query = getSession().createQuery lGt:.p{NG
%^d<go^
(querySentence); =CW> ;h]
query.setFirstResult(page.getBeginIndex()) MGf *+!y,
.setMaxResults(page.getEveryPage()); +w7U7"
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return query.list(); |2=@8_am
} |@~_&g
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} >& 4) :
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RU=\eD
nLOK1@,4
X`3_ yeQc
至此,一个完整的分页程序完成。前台的只需要调用 gnkeJ}K
/i dI-
userManager.listUser(page)即可得到一个Page对象和结果集对象 eso-{W,D
($!uBF-b
的综合体,而传入的参数page对象则可以由前台传入,如果用 o:&8H>(hn]
xkRS?Q g
webwork,甚至可以直接在配置文件中指定。
iDx(qdla
pN)x,<M)
下面给出一个webwork调用示例: <CB%e!~.9
java代码: &Nh
zEl1
Wx8:GBM$2
F3K<-JK+
/*Created on 2005-6-17*/ gKcBx6G
Q
package com.adt.action.user; lXF7)H&T
rT=C/SKP
import java.util.List; KxD/{0F
EP"Z 58&$R
import org.apache.commons.logging.Log; op/_:#&'
import org.apache.commons.logging.LogFactory; Uf|uFGb
import org.flyware.util.page.Page; )o~/yB7
$f _C~O
import com.adt.bo.Result; m+(g.mvK>
import com.adt.service.UserService; vQp'bRR
import com.opensymphony.xwork.Action; Zoc4@%
n
~-[!>1!%
/** 5Po:$(
* @author Joa +$#<gp"
*/ pKpB
publicclass ListUser implementsAction{ "O-X*>?f
EADN
privatestaticfinal Log logger = LogFactory.getLog #t;]s<
)hl7)~S<
(ListUser.class); 10h;N[
8V}|(b#
private UserService userService; ;N(L,
0%<
hj
private Page page; t)Cf]]dV
t#@z_Mn\
privateList users; x/CM)!U)
P
4t@BwU$
/* 6Q\|8a
* (non-Javadoc) =4'V}p
* MUsF
* @see com.opensymphony.xwork.Action#execute() 9a=>gEF],@
*/ f^*Yqa
publicString execute()throwsException{ Woj5
yr
Result result = userService.listUser(page); & !ds#-
page = result.getPage(); iNfAn&
users = result.getContent(); b9#(I~}
return SUCCESS; kW2DKr-[
} RD"-(T
i}zz!dJTE
/** Tg"? TZO~
* @return Returns the page. @MVul_@6
*/ |U;O HS
public Page getPage(){ 8AFc=Wx
return page; Hi=</ Wy;
}
j5Da53c#^
Ihf)gfHj
/** Pzq^x]
* @return Returns the users. AEaN7[PQx|
*/ |nWEuKHy
publicList getUsers(){ ?T_MP"
return users; g)^s+Y
} EpNN!s=Q
\/<VJB
uV
/** 7I'C'.6iM
* @param page ~
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* The page to set. w&p(/y
*/ 7 s{vou
publicvoid setPage(Page page){ pZlsDM/=
this.page = page; * 30K}&T
} ohqThl
$l"%o9ICG
/** =?0v,;F9|
* @param users !L9OJ1F
* The users to set. s5{=lP
*/ l*z%Jw
publicvoid setUsers(List users){ |u?VlRt
this.users = users; 1s@QsZ3
} 2/r8%Sq
,3 /o7 '
/** Sx QA*}N
* @param userService c'tQA
* The userService to set. #:0-t!<0C
*/ Nj3iZD|
publicvoid setUserService(UserService userService){ u%e~a]
this.userService = userService; -W1p=od
} j\IdB:}j
} ws5Ue4g|
z9[TjTH^}T
WYTqQqQk
qE[YZ(/f0&
vs=q<Uw)
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, "lw|EpQk`
|&JeJ0k>~
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 c/tB_]
hBpa"0F
么只需要: O#ZZ PJ"
java代码: PBb&.<
9/29>K_
PjEJC@n
<?xml version="1.0"?> 1J"9Y81
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork $Q8
&TM}E
5[SwF&zZ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- SDil\x
9/{ zS3h3
1.0.dtd"> 8!Wh`n<
').)0;
<xwork> \ m~?yq8H
Zf@B<
m
<package name="user" extends="webwork- 30uPDDvar
3._
ep
interceptors"> 6 Ln~b <I
T9Q3I
<!-- The default interceptor stack name o=($'(1
hA5')te<