Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 BUuU#e5
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^G(/;c*=
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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.& B
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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 ~-"<)XPe
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分页支持类: W|go*+`W%
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java代码: 91Cg
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package com.javaeye.common.util; lL*k!lNs
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import java.util.List; dMA"% R
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publicclass PaginationSupport { R!v ?d2
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publicfinalstaticint PAGESIZE = 30; fP>K!@!8
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privateint pageSize = PAGESIZE; o'W[v0>
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privateList items; ^,Sl^ 9K
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privateint totalCount; [WOLUb
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privateint[] indexes = newint[0]; ]LvpYRU$P
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privateint startIndex = 0; k$V.hG|6M
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public PaginationSupport(List items, int :v_H;UU
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totalCount){ P=)&]Pz
setPageSize(PAGESIZE); xD f<@
setTotalCount(totalCount); ))M; .b.D
setItems(items); -{
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setStartIndex(0); [!@&t:A
} rb+&]
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public PaginationSupport(List items, int k1A64?p
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totalCount, int startIndex){ $K)9(DD
setPageSize(PAGESIZE); oG! S(95
setTotalCount(totalCount); cLN(yL
setItems(items); 2
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setStartIndex(startIndex); _,hhO
} $<)k-Cf
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public PaginationSupport(List items, int Pg3O )D9
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); aqTMOWyeu
setTotalCount(totalCount); SwESDo)
setItems(items); b"+J8W
setStartIndex(startIndex); q%u;+/|l
} w5I
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publicList getItems(){ d%$'Y|
return items; P)?)H]J"
} "{0
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publicvoid setItems(List items){ ni#!Gxw
this.items = items; hP4*S^l
} kc d~`+C
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publicint getPageSize(){ /cBQE=]6
return pageSize; t:m2[U_}
} ;Ry
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publicvoid setPageSize(int pageSize){ $=8?@My<
this.pageSize = pageSize; A&i
} 7d0E9t;W
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publicint getTotalCount(){ n/_cJD\
return totalCount; [c@14]e
} 4'pg>;*.
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publicvoid setTotalCount(int totalCount){ ~%9ofXy
if(totalCount > 0){ |q?I(b4 Q@
this.totalCount = totalCount; 9?)r0`:#
int count = totalCount / "M*Pt
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pageSize; |9)Q =(
if(totalCount % pageSize > 0) %gB 0\C
count++; 4a;8XAl
indexes = newint[count]; (o,&P9
for(int i = 0; i < count; i++){ ?^9TtxM
indexes = pageSize * ?U]/4]
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} RaFk/mSw
}else{ ~:."BA
this.totalCount = 0; NfcQB;0
} xq',pzN
} jp2AU,Cl
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publicint[] getIndexes(){ zzfwI@4
return indexes; 4NxtU/5-sU
} IEV3(qzt
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publicvoid setIndexes(int[] indexes){ LQSno)OZ
this.indexes = indexes; ;p%a!Im_<
} uQ#3;sFO
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publicint getStartIndex(){ _Tyj4t0ElV
return startIndex; D,+I)-k<
} Q nikgV
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publicvoid setStartIndex(int startIndex){ -\yaP8V
if(totalCount <= 0) =rS z>l
this.startIndex = 0; 4f~hd-z
elseif(startIndex >= totalCount) ^1U2&S
this.startIndex = indexes XiI@Px?FL
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[indexes.length - 1]; |{HtY
elseif(startIndex < 0) s,ZJ?[/
this.startIndex = 0; c]O3pcU
else{ EKf"e*|(L
this.startIndex = indexes R%XbO~{u
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[startIndex / pageSize]; ]c8lZO>
} _I+#K M
} kc `Q-
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publicint getNextIndex(){ +2`RvQN
int nextIndex = getStartIndex() + ws4a(1
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pageSize; swuW6p
if(nextIndex >= totalCount) MT BN&4[
return getStartIndex(); 25h.u>6@{
else ]1rr$f9
return nextIndex; T<~NB5&f
} 71nXROB
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publicint getPreviousIndex(){ *nU7v3D
int previousIndex = getStartIndex() - ]~CGzV
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pageSize; azz6_qk8
if(previousIndex < 0) FVsVY1
return0; 'x
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else >f4H<V-
return previousIndex; \MQ|(
} ;OTD1=
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} &%L1n?>Q}
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抽象业务类 G/\t<>O8o
java代码: 6",1JH,;p
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/** 3D[IZ^%VtM
* Created on 2005-7-12 O8TAc]B
*/ ,ClGa2O
package com.javaeye.common.business; ZJ'#XZpr
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import java.io.Serializable; ?@6N EfQf
import java.util.List; 7NV1w*>/
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import org.hibernate.Criteria; ihBlP\C
import org.hibernate.HibernateException;
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import org.hibernate.Session; l4u_Z:<w
import org.hibernate.criterion.DetachedCriteria; |E&a3TQW
import org.hibernate.criterion.Projections; Z\D!'FX
import s6%% /|
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org.springframework.orm.hibernate3.HibernateCallback; i[sHPEml(5
import $3zs?Fd`
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org.springframework.orm.hibernate3.support.HibernateDaoS R$k4}p
pca `nN!
upport; wO/}4>\
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import com.javaeye.common.util.PaginationSupport; n|sP0,$N1
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public abstract class AbstractManager extends NK;%c-r0v7
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HibernateDaoSupport { .w/w]
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privateboolean cacheQueries = false; K?o( zh;
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privateString queryCacheRegion; {fFZ%$
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publicvoid setCacheQueries(boolean `w';}sQA7
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cacheQueries){ 8Y?zxmwn]
this.cacheQueries = cacheQueries; W{:^P0l
} gpDH_!K
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publicvoid setQueryCacheRegion(String /5 yjON{
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queryCacheRegion){ S^(OjS
this.queryCacheRegion = Z>
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queryCacheRegion; {~q"Y]?
} UgI0
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publicvoid save(finalObject entity){ YbAa@Sq@
getHibernateTemplate().save(entity); NV\t%/ ?
} M|8vP53=q
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publicvoid persist(finalObject entity){ VF[$hs
getHibernateTemplate().save(entity); 0x BO5[w,Y
} HXV4E\JA
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publicvoid update(finalObject entity){ ^f6pw!
getHibernateTemplate().update(entity); 3{c6)vR2
} xb{G:v
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publicvoid delete(finalObject entity){ Nini8@d
getHibernateTemplate().delete(entity); xs#g
} h pf,44Kg
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publicObject load(finalClass entity, E;v#'
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finalSerializable id){ "06t"u<%
return getHibernateTemplate().load #BtJo:
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(entity, id); )?`G"(y
} _43'W{%
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publicObject get(finalClass entity, Ymvd3> _
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finalSerializable id){ SG$V%z"e
return getHibernateTemplate().get
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(entity, id); LNNwy:_ !
} XrUc`
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publicList findAll(finalClass entity){ 'G>$W+lT^
return getHibernateTemplate().find("from vKO/hZBh
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" + entity.getName()); &9Kni/
} ;yu#Bs
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publicList findByNamedQuery(finalString /@ww"dmqU
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namedQuery){ WAt= T3
return getHibernateTemplate [s{ B vn
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().findByNamedQuery(namedQuery); Fy 1- >~
} ;\g0*b(
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publicList findByNamedQuery(finalString query, $c{fPFe-
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finalObject parameter){ Xj9\:M-
return getHibernateTemplate ?}e^-//*i
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().findByNamedQuery(query, parameter); F| jl=i
} =Y- .=}jp;
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publicList findByNamedQuery(finalString query, 72CHyl`|l
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finalObject[] parameters){ B[3u,<opFU
return getHibernateTemplate c)3.AgT
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().findByNamedQuery(query, parameters); u69UUkG
} _\.4ofK(
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publicList find(finalString query){ '}^qz#w
return getHibernateTemplate().find .07"I7
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(query);
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} dS8ydG2
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publicList find(finalString query, finalObject aGd
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parameter){ A`#?Bj
return getHibernateTemplate().find OxPl0-]t
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(query, parameter); O/U? Wq
} 'QQq0.
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public PaginationSupport findPageByCriteria xL*J9&~iG
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(final DetachedCriteria detachedCriteria){ cQ]c!G|a4
return findPageByCriteria p+8o'dl8=
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); n5%\FFG0M
} c4u/tt.)
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public PaginationSupport findPageByCriteria suzK)rJ9i
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(final DetachedCriteria detachedCriteria, finalint R `Fgne$4
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startIndex){ 'pT13RFD
return findPageByCriteria < =~=IZ)
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(detachedCriteria, PaginationSupport.PAGESIZE, QJj='+R>
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startIndex); ]tXIe?>9
} o">~ObR
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public PaginationSupport findPageByCriteria n
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(final DetachedCriteria detachedCriteria, finalint Z1jxu;O(
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pageSize, 6}m `_d?
finalint startIndex){ 9tU"+
return(PaginationSupport) (~eS$8>.
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getHibernateTemplate().execute(new HibernateCallback(){ Arg/ge.y
publicObject doInHibernate {ZrlbDQX
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(Session session)throws HibernateException { aPzn4}~/_
Criteria criteria = dVYY:1PS
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detachedCriteria.getExecutableCriteria(session); ?IYu"UO<)|
int totalCount = *~g*J^R}
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((Integer) criteria.setProjection(Projections.rowCount y~\ujp_5w
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()).uniqueResult()).intValue(); h$kz3r;b,"
criteria.setProjection C{}PO u
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(null); t 8 6w&
List items = 'x{oAtCP9
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criteria.setFirstResult(startIndex).setMaxResults #%Bt!#
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(pageSize).list(); -'g>i
PaginationSupport ps = 2=- .@,6
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new PaginationSupport(items, totalCount, pageSize, 9:4S[mz/hD
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startIndex); aSvv(iV
return ps; TdgK.g 4
} UP^8Yhdo
}, true); o[cOL^Xd1
} TG}owG]]
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public List findAllByCriteria(final ,Q56A#Y\
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DetachedCriteria detachedCriteria){ f-enF)z
return(List) getHibernateTemplate `jGeS[FhR
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().execute(new HibernateCallback(){ @w8}]S
publicObject doInHibernate 4`Ud\Jm[s
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(Session session)throws HibernateException { /IWAU)A0
Criteria criteria = e&;e<6l&{
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detachedCriteria.getExecutableCriteria(session); 9$\s
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return criteria.list(); 6?F88;L
} E`oA(x7l
}, true); 7A\`
} zuLW'a6F-
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public int getCountByCriteria(final d5l42^Z
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DetachedCriteria detachedCriteria){ :|s8v2am
Integer count = (Integer) _li3cXE
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getHibernateTemplate().execute(new HibernateCallback(){ f256;3n
publicObject doInHibernate $Aw@xC^!
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(Session session)throws HibernateException { }n==^2
Criteria criteria = VO:4wC"7
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detachedCriteria.getExecutableCriteria(session); 9~Dg<wQ
return j+_fHADq
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criteria.setProjection(Projections.rowCount BTkx}KK
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()).uniqueResult(); P$ o bID
} !1)aie+p6
}, true); Mh7m2\fLbd
return count.intValue(); wD9K\%jIr!
} X`D2w:
} AT"gRCU$4
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用户在web层构造查询条件detachedCriteria,和可选的 <T_3s\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 @N Yl4N
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PaginationSupport的实例ps。 )=~&l={T
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ps.getItems()得到已分页好的结果集 D^6*Cwb
ps.getIndexes()得到分页索引的数组 \(\a=
ps.getTotalCount()得到总结果数 *?X&Y8Kf
ps.getStartIndex()当前分页索引 z(\aJW
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 #kC~qux^
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ukR0E4p
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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 <Q|\mUS6
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一下代码重构了。 W;OGdAa_
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我把原本我的做法也提供出来供大家讨论吧: A^OwT#
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首先,为了实现分页查询,我封装了一个Page类: IBT>&(cnV
java代码: W3.[d->X
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/*Created on 2005-4-14*/ 9kD#'BxC
package org.flyware.util.page; JQM_96\
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/** 1-gM)x{Jr
* @author Joa Ux_tzd0!
* `PUqz&
*/ bsQ'kBD
publicclass Page { /]U$OP*0
if'=W6W
/** imply if the page has previous page */ o-8{C0>:
privateboolean hasPrePage; wC{sP"D
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/** imply if the page has next page */ 5=TgOS]R
privateboolean hasNextPage; e4YfJd
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/** the number of every page */ f+:iz'b#U
privateint everyPage; Exwd,2>
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/** the total page number */ ='"Yj
privateint totalPage; *ra)u-
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/** the number of current page */ ;#Po}8Y=
privateint currentPage; LDg9@esi
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/** the begin index of the records by the current :I#.d7`uk
q{9vY:`[
query */ #eJfwc1JY
privateint beginIndex; ':4ny]F
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/** The default constructor */ nFni1cCD
public Page(){ sPK ]:iC
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} ^y>V-R/N
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/** construct the page by everyPage [],[LkS
* @param everyPage Oem1=QpaC
* */ Sj ovL@X
public Page(int everyPage){ F>.y>h
this.everyPage = everyPage; rRevyTs
} `*U@d%a
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/** The whole constructor */ ytj});,>
public Page(boolean hasPrePage, boolean hasNextPage, <);j5)/
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0/~p1SSun
int everyPage, int totalPage, :awa
int currentPage, int beginIndex){ :+YHj)mN
this.hasPrePage = hasPrePage; N)(m^M(~0
this.hasNextPage = hasNextPage; }<G
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this.everyPage = everyPage; Rc)]A&J
this.totalPage = totalPage; "0!#De
this.currentPage = currentPage; Z(:\Vj"
this.beginIndex = beginIndex; K14.!m
} dtuCA"D
*`OXgkQ
/** OC5oxL2HTe
* @return _
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* Returns the beginIndex. q!&:y7O8
*/ <2*+Y|Lk2
publicint getBeginIndex(){
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return beginIndex; Cdl"TZ<
} T72Li"00
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/** Q-,
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* @param beginIndex T>|+cg
* The beginIndex to set. fwtsr>SV
*/ g?1bEOA!
publicvoid setBeginIndex(int beginIndex){ v*excl~
this.beginIndex = beginIndex; +2E~=xX
} :SFf}
V13^SVM
/** H"+|n2E^
* @return b0f6?s
* Returns the currentPage. 937<:zo:
*/ 5UL5C:3R9
publicint getCurrentPage(){ Gyu =}
return currentPage; $LR~c)}1I
} &hpznIN
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/** F[ ^ p~u{
* @param currentPage sC.cMZ e
* The currentPage to set. ">|L<
*/ TFc/`
publicvoid setCurrentPage(int currentPage){ I<lkociUCG
this.currentPage = currentPage; @)ozgs@e
} IL8&MA%
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/** GB>h8yXH
* @return ,J*#Ixe}
* Returns the everyPage. VjSbx'i
*/ o,1Fzdh6(
publicint getEveryPage(){ .@(MNq{"6
return everyPage; aj+I+r"~
} 1eqFMf
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/** RV5;EM)~[
* @param everyPage i#lO{ ]
* The everyPage to set. %gEfG#S
*/ 5PHAd4=bJ
publicvoid setEveryPage(int everyPage){ 0w^awT<$6
this.everyPage = everyPage; ~o;*{ Q
} \4q1<j
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/** 2L2)``*
* @return =dC5q{
* Returns the hasNextPage. WAw} ?&k
*/ FCr> $
publicboolean getHasNextPage(){ z 2V_nkI
return hasNextPage; :'dH)yO
} Yv;18j*<
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/** _Ai\XS
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* @param hasNextPage i3y>@$fRL\
* The hasNextPage to set. QXT*O
*/ 0/%VejZ'
publicvoid setHasNextPage(boolean hasNextPage){ G5 x%:,n
this.hasNextPage = hasNextPage; FU~:9EEx
} zTt6L6:u
xqzdXL}
/** FZtIC77X5
* @return 3m`y?Dd
* Returns the hasPrePage. |N>TPK&Xt
*/ &mvC<_1n
publicboolean getHasPrePage(){ Z4Qq#iHZR
return hasPrePage; Ih0kdi
} {7X80KI
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/** wN! 5[N"
* @param hasPrePage 3+jqf@ fO
* The hasPrePage to set. fL&bN[XA"$
*/ Xn3Ph!\Z5e
publicvoid setHasPrePage(boolean hasPrePage){ {^
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this.hasPrePage = hasPrePage; 4h~o>(Sq
} pTJJ.#$CEF
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/** 3"hPplE
* @return Returns the totalPage. qMe$Qr8
* <Cw)S8t
*/ e[7n`ka
'
publicint getTotalPage(){
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return totalPage; y\&`A:^[ A
} 8?O6IDeW
!8U\GR `
/** 0"L_0 t:
* @param totalPage bEE'50D
* The totalPage to set. Og`w ~!\
*/ i7f/r.
publicvoid setTotalPage(int totalPage){ z\8Kz ]n~
this.totalPage = totalPage; 1^zpO~@S
} TnqspS2;R
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} d-=/@N!4e
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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 .ns1;8
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个PageUtil,负责对Page对象进行构造: g,!6,v@
java代码: Lh6G"f(n
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/*Created on 2005-4-14*/ ^E8XPK]-~
package org.flyware.util.page; :Uf\r
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import org.apache.commons.logging.Log; Bg*Oj)NM
import org.apache.commons.logging.LogFactory; 2Ke?*
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/** (8u.Xbdh
* @author Joa MS-}IHO
* $UAmUQg)}_
*/ pzP~,cdf
publicclass PageUtil { N*N@wJy:5
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n\?!
privatestaticfinal Log logger = LogFactory.getLog ~*9
vn Z@
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(PageUtil.class); e.%`
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/** %l!Gt"\xm
* Use the origin page to create a new page E=.4(J7K
* @param page
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* @param totalRecords %Uj7g>
* @return q[#2`
*/ }u0t i"V
publicstatic Page createPage(Page page, int FWv-_
b/:&iG;
totalRecords){ V8w!yc
return createPage(page.getEveryPage(), <J4|FOz!=
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page.getCurrentPage(), totalRecords); vkWh2z
} $bRakF1'S
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/** mrR~[533j
* the basic page utils not including exception 48JD >=@7
A`x_M!m
handler <\<[J0
* @param everyPage yES+0D 5<
* @param currentPage XS5*=hv:
* @param totalRecords I;]Q}SUsm
* @return page hm"i\JZ3N
*/ #;59THdtPk
publicstatic Page createPage(int everyPage, int E? 1"&D
m
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currentPage, int totalRecords){ M}|<#
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everyPage = getEveryPage(everyPage); .'QE o
currentPage = getCurrentPage(currentPage); bM[!E 8dF
int beginIndex = getBeginIndex(everyPage, 9Ml^\|
,2\?kPoc8
currentPage); &eYnO~$!
int totalPage = getTotalPage(everyPage, X_yAx)Do
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totalRecords); <smi<syx
boolean hasNextPage = hasNextPage(currentPage, LWQ.!;HY p
VPG+]>*
totalPage); {kGcZf3h
boolean hasPrePage = hasPrePage(currentPage); V7}5Zw1
% c[Q_
returnnew Page(hasPrePage, hasNextPage, >\=~2>FCD
everyPage, totalPage, nX,2jT;@L
currentPage, WqX#T
*7: )k
beginIndex); H'N$Vv2q
} ~^#F5w"
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privatestaticint getEveryPage(int everyPage){ f>$Ld1
return everyPage == 0 ? 10 : everyPage; ;Ml??B]C
} M{ #
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privatestaticint getCurrentPage(int currentPage){ %Z|]"=;6
return currentPage == 0 ? 1 : currentPage; . C_\xb
} g wM~W
Sn 3@+9J
privatestaticint getBeginIndex(int everyPage, int t[Dg)adc
n{oRmw-
currentPage){ gY'w=(/`
return(currentPage - 1) * everyPage; ?@W=bJ8{
} r?Y+TtF\e
HF@K$RPK
privatestaticint getTotalPage(int everyPage, int 3,qq\gxB
^zjQ(ca@"x
totalRecords){ 0@;kD]Z
int totalPage = 0; @Y2"=QVt
JN;92|x
if(totalRecords % everyPage == 0) V. sIiE
totalPage = totalRecords / everyPage; UO%VuC5B
else dxm_AUM
totalPage = totalRecords / everyPage + 1 ; 1QHCX*_
BPAz.K Q
return totalPage; s':fv[%
} a|B^%
yxfV|ox
privatestaticboolean hasPrePage(int currentPage){ _ PC}`Y'&
return currentPage == 1 ? false : true; )3O0:]<H
} u@!iByVAg
W`zY\]
privatestaticboolean hasNextPage(int currentPage, rSTc4m1R
A/kRw'6
int totalPage){ rx^vh%/
Q!
return currentPage == totalPage || totalPage == v] *(Wd~|
F^iv1b
0 ? false : true; {4\hxyw
} )IIQ{SwQq
~'/I[y4t
^Pc>/lY$Q%
} oYWcX9R
-BWkPq!
p_hljgOV
Rg*zUfu5%o
{V&
2k9*
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 >-0b@ +j
o^59kQT
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 y]OW{5(
\Yv<TzJ9
做法如下: )]2yTG[
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 51oZw%os=
%9|=\#
G
的信息,和一个结果集List: zdA:K25"
java代码: l6.#s3I['
7#Qa/[? D
^
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/*Created on 2005-6-13*/ H~~I6D{8
package com.adt.bo; W-Cf#o
k
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import java.util.List; w;$@ </
fTi,S)F'
import org.flyware.util.page.Page; x>Ah4ad
4%WV)lt
/** D5X;hd
* @author Joa Y^gK^?K
*/ H[ %Fo
publicclass Result { sY,!Ir`/`
3mn0
private Page page; o"^}2^)_SR
_C?<re3*
private List content; v>Il#
`4s5yNUi=
/** Co8b0-Z
* The default constructor RIX0AE
*/ lh*m(
public Result(){ S[UHx}.
super(); lwLK#_5u
} jG{}b6
-5\aL"?4
/** ,TU!W|($
* The constructor using fields G*BM'^0+
* O#A1)~
* @param page :EyH'v
* @param content MAR
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*/ $XFG1?L!
public Result(Page page, List content){ #RJy
this.page = page; ;:*o
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this.content = content; f7X#cs)a
} c}mJ6Pt
VO(Ck\i}
/** sVkR7
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* @return Returns the content. %R;cXs4r
*/ )F? 57eh
publicList getContent(){ h.
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return content;
-/
} aJMh>
.mDqZOpf=4
/** T-&CAD3 ,O
* @return Returns the page. 2x e_Q70II
*/ w0SzK-&
public Page getPage(){ j %TYyL-
return page; :G^`LyOM
} *U54x
/w|
V-=$:J"J'\
/** g) v"nNS
* @param content wt2S[:!p
* The content to set. *"fg@B5
*/ ?xQlX%&`6
public void setContent(List content){ *BXtE8
BU
this.content = content; _$ixE~w-!
} #j-,#P@
!+uMH!
/** sQJM 4'8f
* @param page +1d\ZZA|6&
* The page to set. [=U7V;5($
*/ F5
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publicvoid setPage(Page page){ X8Sk
this.page = page; 7Wb.(` a<
} Z$zUy|s[
} Ysr{1! K
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n[4Nu`E9
@O45s\4-*
@0
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2. 编写业务逻辑接口,并实现它(UserManager, 9Biw!%a
0[v :^H
UserManagerImpl) !'{j"tv
java代码: J.<eX=<
xZ@Y`2A':
}2NH>qvY
/*Created on 2005-7-15*/ $--PA$H27
package com.adt.service; ]#BXaBVMY
zl:
u@!'
import net.sf.hibernate.HibernateException; y5Pw*?kn
Ap!UX=HBb
import org.flyware.util.page.Page; fwq|8^S@
~JZLfw
import com.adt.bo.Result; Q ,;x;QR4
[CUJ A
/** .\d0lJSr
* @author Joa E`?BaCrG~
*/ ]~K&mNo
publicinterface UserManager { %ly;2HIk
Qy70/on9
public Result listUser(Page page)throws 3?O|X+$p
LqUvEq
HibernateException; xc/|#TC8?
jSVO$AW~C
} aDOH3Ri0K!
(C3d<a\:
4O`h%`M
IL\mFjZ'
7S1!|*/
I
java代码: h7y*2:l6
IWWFl6$-
}2r08,m
/*Created on 2005-7-15*/ rL
s6MY
package com.adt.service.impl; RdDcMZ
5rWRE-
import java.util.List; m[bu(q z
/,>.${,;u
import net.sf.hibernate.HibernateException; X3-1)|g !z
,9pi9\S
import org.flyware.util.page.Page; kp6x6%{K\
import org.flyware.util.page.PageUtil; &q<8tTW5
sy`s$Ed!
import com.adt.bo.Result; -J30g\
import com.adt.dao.UserDAO; )aC+qhh
import com.adt.exception.ObjectNotFoundException; Y{yr-E #~M
import com.adt.service.UserManager; q
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sWC"^ S o
/** 8$vH&HdI
* @author Joa UZ!hk*PF
*/ bGJUu#
publicclass UserManagerImpl implements UserManager { \nHlI=!P
%PS-nF7v
private UserDAO userDAO; LF~#4)B
B1M/5cr.
/** 2o$8CR;
* @param userDAO The userDAO to set. (=/F=,w
*/ ,$]q2aL
publicvoid setUserDAO(UserDAO userDAO){ >gZz`CH
this.userDAO = userDAO; ]xG8vy
} m?j!0>
`Z/ IW
/* (non-Javadoc) U.aa iX7
* @see com.adt.service.UserManager#listUser ;Wa{q.)
%p9bl ,x
(org.flyware.util.page.Page) .vv*bx
*/ ;Kf|a}m -
public Result listUser(Page page)throws 3ngLEWT
m%[t&^b}T
HibernateException, ObjectNotFoundException { [&CM-`
N
int totalRecords = userDAO.getUserCount(); //Gvk|O1
if(totalRecords == 0) p*0Ve21i,
throw new ObjectNotFoundException [hL1PWKs
NXBOo
("userNotExist"); )DmiN ^:
page = PageUtil.createPage(page, totalRecords); f}X8|GlBo
List users = userDAO.getUserByPage(page); m GhJn
returnnew Result(page, users); IDh`0/i]
} {^W,e ^:
sAoM=n}!
} ~vGtNMQg
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j7 =3\SO
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ik*)j
#/Fu*0/)`
询,接下来编写UserDAO的代码: DOVX$N$3
3. UserDAO 和 UserDAOImpl: ZZU 8B?)
java代码: R2aK5~
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:$
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/*Created on 2005-7-15*/ 4nH91Z9=
package com.adt.dao; K$cIVsfr
{p|%hhTK%
import java.util.List; WcwW@cY7\
RQCQGa^cP
import org.flyware.util.page.Page; ^<\} Y
J md
?
import net.sf.hibernate.HibernateException; `Kw"XGT
7NB 9Vu|gD
/** c^Jgr(Ow
* @author Joa 4)HWPX
*/ r?nV
Sb|[
publicinterface UserDAO extends BaseDAO { )H9*NB8%
GR ?u?-
publicList getUserByName(String name)throws qH
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iW@Vw{|i I
HibernateException; Ws*PMK.0
Rca
Os
publicint getUserCount()throws HibernateException; ]cqZ!4?_
R96o8#7Uv
publicList getUserByPage(Page page)throws 0r-lb[n8i
F|Dz]ar
HibernateException; Ui|a}`c
!)/iRw9re
} Z!-<rajl
'<D `:srV
boF4d'g"
W
B*`zCM
PyT}}UKj:
java代码: G#n^@kc*,
mU+FQX
HCjn9
/*Created on 2005-7-15*/ aT1CpY=T|.
package com.adt.dao.impl; 5Vqmv<F;$Z
;Co[y=Z
import java.util.List; OgXZ-<'
+:"6`um|
import org.flyware.util.page.Page; "dK|]w8
F%.9fUo
import net.sf.hibernate.HibernateException; L_~I~
import net.sf.hibernate.Query; /y](mu "!
UJz4>JF
import com.adt.dao.UserDAO; 4ljvoJ}xjr
dx13vZ3[U
/** Jl>at
* @author Joa Ie2w0Cs28
*/ W\>^[c/
public class UserDAOImpl extends BaseDAOHibernateImpl (]}x[F9l
/G)KkBC
implements UserDAO { /h7>Z9T
Tw}?(\ya
/* (non-Javadoc)
&6\r
* @see com.adt.dao.UserDAO#getUserByName KO-Zz&2f
oBRm\8 2|
(java.lang.String) z<oE!1St
*/ *CH!<VB/
publicList getUserByName(String name)throws i9&K
h{W$ fZc<
HibernateException { V`g\ja*Y
String querySentence = "FROM user in class lTV@b&
8Fd1;G6
com.adt.po.User WHERE user.name=:name"; C`NBHRa>
Query query = getSession().createQuery 0+K`pS'
|t&G&)~:
(querySentence); n&0mz1rw
query.setParameter("name", name); l$k]O
return query.list(); yD3bl%uZ
} GhG%>U#&a
;#Jq$v)D
/* (non-Javadoc) ]k'#g Z$
* @see com.adt.dao.UserDAO#getUserCount() ?qf:_G
*/ u [V4OU}%
publicint getUserCount()throws HibernateException { ~t{D5#LVHa
int count = 0; ZL4l
(&"
String querySentence = "SELECT count(*) FROM %uGleY]~
Vqa5RVnI
user in class com.adt.po.User"; nd $H
3sf
Query query = getSession().createQuery WZ^{zFoZ
OwG6i|q
(querySentence); D'7A2 f
count = ((Integer)query.iterate().next b$dJ?%W
OLk9A
()).intValue(); 1.Haf
return count; y2z{rd
} Rr o?q
r+t ,J|V
/* (non-Javadoc) m0=cMVCA!
* @see com.adt.dao.UserDAO#getUserByPage "%{,T
opm?':Qst
(org.flyware.util.page.Page) E:08%4O
*/ %/UV_@x&
publicList getUserByPage(Page page)throws OZ(Dpx(Q
;Ay>+M2O
HibernateException { =E&b=
String querySentence = "FROM user in class wVx,JL5Jr
C-Nuy1o
com.adt.po.User"; kcLj Kp
Query query = getSession().createQuery S:/{
r0)JUc}Fyq
(querySentence); yOX&cZ[
query.setFirstResult(page.getBeginIndex()) tRLE,(S,-
.setMaxResults(page.getEveryPage()); !cRfZ
return query.list(); }sf YCz
} DW1@<X
F(d:t!
} M0RRmW@f.a
6XdWm
bsB},pc
j3
6,w[Y:
^`tk/#h\9F
至此,一个完整的分页程序完成。前台的只需要调用 F4GP7]
i*X{^A73"
userManager.listUser(page)即可得到一个Page对象和结果集对象 yC
W*fIaq
wAw42{M
的综合体,而传入的参数page对象则可以由前台传入,如果用 gXLCRn!iR
zm3-C%:Bw
webwork,甚至可以直接在配置文件中指定。 !6M Bxg >
0Y7$d`
下面给出一个webwork调用示例: <x0)7xX
java代码: 2R~6<W+&:>
M ~als3
I6+2>CUGo
/*Created on 2005-6-17*/ ^pj>9%
package com.adt.action.user; uG;?vvg>
Z(p*Z,?u
import java.util.List; ~F;CE"3A
!K[/L<
Kv
import org.apache.commons.logging.Log; {&-#s#&
import org.apache.commons.logging.LogFactory; @}(SR\~N]
import org.flyware.util.page.Page; 6JSY56v
\]I
import com.adt.bo.Result; #EJP(wXa
import com.adt.service.UserService; RwW$O@0
import com.opensymphony.xwork.Action; \ZMP_UU(
.$Y?
W<
/** }S */b1
* @author Joa 4@6<
*/ ]KWK}Zyi
publicclass ListUser implementsAction{ ?KB@Zm+#~
it)ZP H
privatestaticfinal Log logger = LogFactory.getLog B!}BM}r
9*\g`fWc}{
(ListUser.class); ]boE{R!I
v5T`K=qC
private UserService userService; vM(Xip7
0Gsu
private Page page; o\4CoeG
I^G^J M!
privateList users; O#EqG.L5
n(>C'<otj
/* ,hWcytzEw
* (non-Javadoc) & fu z2xv
* +AoP{x$Ia
* @see com.opensymphony.xwork.Action#execute() ,[X_]e;
*/ Uyk,.*8"
publicString execute()throwsException{ tuLH}tkNY
Result result = userService.listUser(page); )3%@9
page = result.getPage(); \}#@9=
users = result.getContent(); 3z3_7XI
return SUCCESS; Ie@Jb{x
} MQ` %``
a9l8{3
/** Od{jt7 <j#
* @return Returns the page. [b/o$zR
*/ &94W-zh
public Page getPage(){ Fp%Ln(/m
return page; Svw<XJ
} RlRs}yF
.'T 40=7
/** %;|0
* @return Returns the users. UpfZi9v?W
*/ bL`eiol6
publicList getUsers(){ 0V`[Zgf
return users; {^m Kvc
} |^( M{
.Djta|puu
/** (3;@^S4&w
* @param page cyQBqG
* The page to set. HBiBv-=,
*/ N3%*7{X
9
publicvoid setPage(Page page){ Ck'aHe22'
this.page = page; hXB|g[zT
} VhEka#
<f>akT,W
/** h`Tz5% n
* @param users nidr\oFUIn
* The users to set. :iPym}CE
*/ [6tSYUZs
publicvoid setUsers(List users){ `u
XQ z7
this.users = users; f p[,C1U
} "G?Yrh
<1 "+,}'x
/** 1m@^E:w
* @param userService A''pS
* The userService to set. c#cx>wq9
*/ k'3Wt*i
publicvoid setUserService(UserService userService){ )r tomp:X
this.userService = userService; =L]Q2V}
} M(Zc^P}N
} Log|%P\
QLKK.]
&
,hr8
/)L
0`:I#
?cy4&]s
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, wvby?MhPY
>BVoHt~;
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 5:.{oSy7n
19UN*g3(
么只需要: $E!J:Y=
java代码: ,,4
GNbBC
gVR@&bi7
,5Vt]#F5@
<?xml version="1.0"?> 4JyM7ePND}
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork WT\<.Py
EnVuD
9
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 8V/L:h#7
fS&6
1.0.dtd"> |CFRJN-J"
*m+BuGt|
<xwork> aHzHvl
0Q5^C!K
<package name="user" extends="webwork- }hpmO-
RP4Ku9hk
interceptors"> \;X+X,M
V ~{fB~
<!-- The default interceptor stack name Cfu=u *u
muON>^MbC
--> "Zv~QwC
<default-interceptor-ref 5*g]qJF
@~td`Z?1y
name="myDefaultWebStack"/> *iA4:EIP
(qMj-l
<action name="listUser" EbNd=Z'J
G\d$x4CVGc
class="com.adt.action.user.ListUser"> pKG<Nvgz&
<param )RgGcHT@
KJn!Ap
name="page.everyPage">10</param> s"KJiQKGM
<result o`S?
h&