Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 zHL@i0>^
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1#*a:F&re
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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 5JCG2jqx0
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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 gp^5#
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分页支持类: !*m5F8Qm?A
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java代码: *4xat:@{{
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package com.javaeye.common.util; #PanfYR
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import java.util.List; AW_(T\P:u
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publicclass PaginationSupport { (
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publicfinalstaticint PAGESIZE = 30; OQT;zqup
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privateint pageSize = PAGESIZE; jJY"{foWV
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privateList items; lR[qqFR
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privateint totalCount; W4e5Rb4~f"
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privateint[] indexes = newint[0]; O.Iu6D
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privateint startIndex = 0; %8Dzo
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public PaginationSupport(List items, int Eam
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totalCount){ g'=B%eO$j:
setPageSize(PAGESIZE); .I'o
setTotalCount(totalCount); c`WHNky%j
setItems(items); R~jHr
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setStartIndex(0); IS[thbzkZ
} ./D$dbu3
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public PaginationSupport(List items, int @@rEs40
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totalCount, int startIndex){ :l&V]}:7*
setPageSize(PAGESIZE); ^#1.l=s
setTotalCount(totalCount); ?(m
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setItems(items); vR=6pl$|~~
setStartIndex(startIndex); J9Ou+6 u(
} 9,_mS{+B
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public PaginationSupport(List items, int $:j G- r
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totalCount, int pageSize, int startIndex){ CQr<N w
setPageSize(pageSize); $w0lrh[+
setTotalCount(totalCount); @qjfZH@
setItems(items); ;9ly'<up
setStartIndex(startIndex); nJ"YIT1K]p
} ]%Nlv(
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publicList getItems(){ ?wF'<kEH
return items; |),'9
} +sx 8t
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publicvoid setItems(List items){ VY"9?2?/
this.items = items; Ra/Ukv_ v
} RJH,
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publicint getPageSize(){ bY2 C]r(n
return pageSize; xD /9F18
} ?N=m<fn
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publicvoid setPageSize(int pageSize){ 1q3(
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this.pageSize = pageSize; R:AA,^Z
} 1>Dl\czn
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publicint getTotalCount(){ =rQP[ICs!
return totalCount; 7Wa?$6d
} [NIlbjYH
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publicvoid setTotalCount(int totalCount){ #D9e$E(J^
if(totalCount > 0){ ,7)C"
this.totalCount = totalCount; zrv#Xa!O\
int count = totalCount / ^6P3%
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pageSize; fr}Eaa-{^
if(totalCount % pageSize > 0) X _G| hx
count++; :BukUket1e
indexes = newint[count]; K+)%KP
for(int i = 0; i < count; i++){ zYv#:>C8
indexes = pageSize * |Uk"
{
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i; F@!Td(r2
} qG/fE'(j&
}else{ pdb1GDl0q
this.totalCount = 0; CGP3qHrXt
} Bo+DJizu
} a7/-wk
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publicint[] getIndexes(){ C"qU-&*v
return indexes; lvpc*d|K
} X$\i{p9jw
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publicvoid setIndexes(int[] indexes){ w[-Fm+A>
this.indexes = indexes; e{9jn>\,a
} j ! NO|&k
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publicint getStartIndex(){ C4#rA.nF|
return startIndex; oM1
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} (zYy}g#n
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publicvoid setStartIndex(int startIndex){ L~/qGDXC?
if(totalCount <= 0) qxMnp}O
this.startIndex = 0; !epgTN
elseif(startIndex >= totalCount) HXVBb%pP
this.startIndex = indexes L]hXpt
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[indexes.length - 1]; LFp]7Dq
elseif(startIndex < 0) .LRxP#B
this.startIndex = 0; 3PUAH
else{ E%TpJl'U
this.startIndex = indexes 9>#:/g/
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[startIndex / pageSize]; ^D_/=4rz8
} *Sf-;U
} <n\`d
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publicint getNextIndex(){ l0Ti Z
int nextIndex = getStartIndex() + a!c[!
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pageSize; b~C$R[S
if(nextIndex >= totalCount) rspayO<]3
return getStartIndex(); ]AS"z<
else /Go
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return nextIndex; Uo_tUp_Q
} ]Lqt(c
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publicint getPreviousIndex(){ xaKst
p
int previousIndex = getStartIndex() - >Dg#9
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pageSize; DV]7.Bm
if(previousIndex < 0) l??;3kh1
return0; |__=d+M'
else .`Zf}[5[
return previousIndex; <;t)6:N\
} I#FF*@oeM
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} ? {F{;r
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抽象业务类 c| '
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java代码: }GnwY97
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/** ]yX@'f
* Created on 2005-7-12 D;F{1[s(
*/ fd8#Ng"1
package com.javaeye.common.business; %xyX8c{sP
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import java.io.Serializable; c;I, O
import java.util.List; +MO E
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import org.hibernate.Criteria; 8xI`jE"1
import org.hibernate.HibernateException; W)SjQp6
import org.hibernate.Session; mf|pNiQ,
import org.hibernate.criterion.DetachedCriteria; -05U%l1e
import org.hibernate.criterion.Projections; TL)O-
import gS"Q=ZK"
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org.springframework.orm.hibernate3.HibernateCallback; z]$j7 dp
import vh>{_
#
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org.springframework.orm.hibernate3.support.HibernateDaoS azb=(l-
af+}S9To
upport; 8h?X!2Nq
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import com.javaeye.common.util.PaginationSupport; GZ0aOpUWVq
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public abstract class AbstractManager extends ~j,TVY
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HibernateDaoSupport { X#+`e+Df
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privateboolean cacheQueries = false; H]qq ~bO[
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privateString queryCacheRegion; 0B0G2t&hr
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publicvoid setCacheQueries(boolean T2Z[AvNXFk
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cacheQueries){ {=At#*=A
this.cacheQueries = cacheQueries; G79C {|c\
} J/4y|8T/y
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publicvoid setQueryCacheRegion(String J35l7HH
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queryCacheRegion){ #cEq_[yI
this.queryCacheRegion = sdF3cX
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queryCacheRegion; hrM"Zg
} 5(}H
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publicvoid save(finalObject entity){ =
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getHibernateTemplate().save(entity); D$_8rHc\A
} &R\XUxI
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publicvoid persist(finalObject entity){ C"T ,MH
getHibernateTemplate().save(entity); '}O!2W&Y]%
} PF ;YE6
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publicvoid update(finalObject entity){ FH n,]Tfx
getHibernateTemplate().update(entity); ^L~ [+|
}
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); fJ :jk6@
} Nz]aaoO4
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publicObject load(finalClass entity, Z oTNm
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finalSerializable id){ w?ai,Pw
return getHibernateTemplate().load ~&[u]u[
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(entity, id); ._BB+G
} <jL#>L%%
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publicObject get(finalClass entity, $T)d!$
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finalSerializable id){ F>Mr<k=@;
return getHibernateTemplate().get U~g@TfU;
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(entity, id); S1>Z6
} WRMz]|+}4
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publicList findAll(finalClass entity){ j];1"50?
return getHibernateTemplate().find("from n^Au*'
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" + entity.getName()); k <}I<Or
} `]yKM0 Z
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publicList findByNamedQuery(finalString 'Fzuc^G(d
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namedQuery){ s#Q_Gu
return getHibernateTemplate LsotgQ8
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().findByNamedQuery(namedQuery); Hrv),Ce
} wL|7mMM,
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publicList findByNamedQuery(finalString query, = P8~n2V
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finalObject parameter){ w\v&3T
return getHibernateTemplate I_L;T
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().findByNamedQuery(query, parameter); j)<[j&OWw
} 1(F'~i|5
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publicList findByNamedQuery(finalString query, Pb=rFas*C
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finalObject[] parameters){ pgfu+K7?w
return getHibernateTemplate "]9_Fv
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().findByNamedQuery(query, parameters); S%P3ek>3
} `w(sXkeaI
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publicList find(finalString query){ `i{4cT8:
return getHibernateTemplate().find <W9) Bq4
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(query); v @_?iC"`
} |<2JQ[]
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publicList find(finalString query, finalObject IM|Se4;x
@%keTTZ
parameter){ t;~-_{
return getHibernateTemplate().find FrgV@4'2G
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(query, parameter); $/y%[ .
} 7@\GU].2
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public PaginationSupport findPageByCriteria hG[4O3jo\
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(final DetachedCriteria detachedCriteria){ /TG|
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return findPageByCriteria 2w;G4
+;5Wp$M\
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 5D>BV*"
} @<%oIE~]F
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public PaginationSupport findPageByCriteria (#lm#?<)
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(final DetachedCriteria detachedCriteria, finalint V4qZc0<,H
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startIndex){ 6#/LyzZq|
return findPageByCriteria 3 pHn_R
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(detachedCriteria, PaginationSupport.PAGESIZE, CJtr0M<U+
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startIndex); ]r]+yM|
} -y9Pn>~V
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public PaginationSupport findPageByCriteria fa/P%9db
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(final DetachedCriteria detachedCriteria, finalint Rb yF#[}
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pageSize, ``/y=k/au
finalint startIndex){ ?cA8P.?^A
return(PaginationSupport) aslNlH 6
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getHibernateTemplate().execute(new HibernateCallback(){ Rs^jk)Z:)
publicObject doInHibernate "o~N42DLB%
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(Session session)throws HibernateException { `8qT['`#R
Criteria criteria = 20S9/9ll
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detachedCriteria.getExecutableCriteria(session); _-YL!oP
int totalCount = @5JLjCN
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((Integer) criteria.setProjection(Projections.rowCount o
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()).uniqueResult()).intValue(); Qj{$dqmDN
criteria.setProjection `mh-pBVD1
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(null); H,01o5J
List items = j
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criteria.setFirstResult(startIndex).setMaxResults uVoF<={
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(pageSize).list(); )<m=YI
;<
PaginationSupport ps = +6i7,U
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new PaginationSupport(items, totalCount, pageSize, V7Vbl?*n
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startIndex); 9
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return ps; QfKR
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} "Yc^Nc
}, true); L5i#Kh_
} !-
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public List findAllByCriteria(final $4#=#aKW.
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DetachedCriteria detachedCriteria){ - I1cAt
return(List) getHibernateTemplate 5e~ j
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().execute(new HibernateCallback(){ dlU
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publicObject doInHibernate ;H D 4~3
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(Session session)throws HibernateException { {PP ^Rb)
Criteria criteria = FkB6*dm-
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detachedCriteria.getExecutableCriteria(session); VPq5xSc?
return criteria.list(); {66Q" H"I
} @1`W<WP
}, true); *FI5z[8,
} /ynKKJx<Y
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public int getCountByCriteria(final &Sa_%:*D(
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DetachedCriteria detachedCriteria){ "W3n
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Integer count = (Integer) 24.7S LXO
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getHibernateTemplate().execute(new HibernateCallback(){ fwar8
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publicObject doInHibernate C.Wms}XA
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(Session session)throws HibernateException { ?[NTw./'7A
Criteria criteria = QI
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detachedCriteria.getExecutableCriteria(session); ~{3o(gzl
return Wfi:wCqZG
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criteria.setProjection(Projections.rowCount Ah8^^h|TPJ
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()).uniqueResult(); 3thG*^C5
} P^uP$D
}, true); LRqw\fKk[
return count.intValue(); 6@,'m
} Q
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} 6cgpg+-a
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用户在web层构造查询条件detachedCriteria,和可选的 z_[3IAZ
hhh: rmEZl
startIndex,调用业务bean的相应findByCriteria方法,返回一个 af`f*{Co3
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PaginationSupport的实例ps。 f"Vm'0r
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ps.getItems()得到已分页好的结果集 zd*W5~xKg
ps.getIndexes()得到分页索引的数组 nJM9c[Ou^H
ps.getTotalCount()得到总结果数 y<Z#my$`|n
ps.getStartIndex()当前分页索引 Cs6zv>SR
ps.getNextIndex()下一页索引 dmTW]P2
ps.getPreviousIndex()上一页索引 G74a9li@
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 h9)]N&07b
1_dMe%53
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 BW(DaNt^
:n%sU*'T
一下代码重构了。 ,co9f.(w
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我把原本我的做法也提供出来供大家讨论吧: VE S4x%r=
:b3lJ-dB
首先,为了实现分页查询,我封装了一个Page类: uq#h\p|
java代码: K:lT-*+S
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/*Created on 2005-4-14*/ v#YS`];B
package org.flyware.util.page; vSHIl"h
zLIa! -C
/** MWd_6XM
* @author Joa TckR_0LNV
* v2uS6
*/ oJz:uv8Pe.
publicclass Page { 'zD;:wT
w|UKMbRMU]
/** imply if the page has previous page */ Kt&$Si
privateboolean hasPrePage; 0Ts_"p
FO3eg"{N
/** imply if the page has next page */ BBuYO$p
privateboolean hasNextPage; 7`'fUhB!
]mLTF',5
/** the number of every page */ ePcI^}{
privateint everyPage; H*
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/** the total page number */ pmpn^ZR
privateint totalPage; 1069]
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/** the number of current page */ i6\!7D]
privateint currentPage; vS,G<V3B
v%PWr5]
/** the begin index of the records by the current ^zluO
0f}Q~d=QL
query */ '>lPq tdZ
privateint beginIndex; (P52KD[A[
Ok{:QA~#
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/** The default constructor */ 3x;y}:wQa
public Page(){ C9;X6
$\J9F=<a
} jX8 C2}j
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/** construct the page by everyPage tH|Q4C
* @param everyPage =A&*SE o5
* */ Tk|;5^#H
public Page(int everyPage){ .)pRB7O3
this.everyPage = everyPage; lIc9,|FL
} %Fm;LQa ]
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/** The whole constructor */ x%?*]*W
public Page(boolean hasPrePage, boolean hasNextPage, ,8 -_=*
$6x:aG*F
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int everyPage, int totalPage, aKFA&Xnsl
int currentPage, int beginIndex){ )LMuxj
this.hasPrePage = hasPrePage; #WmAkzvq
this.hasNextPage = hasNextPage; 9QQ@Y}
this.everyPage = everyPage; CR PE?CRQF
this.totalPage = totalPage; :W<,iqSCm
this.currentPage = currentPage; [<1+Q =;
this.beginIndex = beginIndex; [q{Txe
} 3 BhA.o
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/** tJF~Xv2L!
* @return GBOmVQ $Hb
* Returns the beginIndex.
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*/ W[Ew6)1T
publicint getBeginIndex(){ AT'$VCYC(
return beginIndex; +jZg%$Q!#
} N#!1@!2BN
9^*YYK}%
/** ='||BxB
* @param beginIndex A VG`r2T
* The beginIndex to set. NX #d}M^V
*/ 8!`.%)- 4
publicvoid setBeginIndex(int beginIndex){ Vwg|? sG_
this.beginIndex = beginIndex; `}Zbfe~
} 1,!\7@<CT
yl+)I
/** K[yJu 4
* @return _eeX]xSSl
* Returns the currentPage. U;dt-3?=.h
*/ 2o}G<7r
publicint getCurrentPage(){ Nc Mq>n
return currentPage; YhK/pt43C
} ){|Lh(
UNLNY,P/!)
/** GYmB xX87
* @param currentPage }uj'BO2?
* The currentPage to set. d3J_IW+8R$
*/ 2*DS_=6o
publicvoid setCurrentPage(int currentPage){ ${,eQ\
this.currentPage = currentPage; wmCV%g\.d:
} ;mKU>F<V
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/** ;m:GUp^[
* @return 8VGXw;(Y,d
* Returns the everyPage. (mr`?LI}
*/ @[Qg}'i
publicint getEveryPage(){ l0 :xQV`
return everyPage; 1gK3=Ys
} !fjU?_[S
MQMy Z:
/** >gLyz2
* @param everyPage n|2-bRK-
* The everyPage to set. zk~ rKQ,
*/ 2l4 i-;
publicvoid setEveryPage(int everyPage){ t|"d#5'
this.everyPage = everyPage; 3t6'5{
} yk6UuI^/
#{cpG2Rs
/** yj9gN}+
* @return PY<V
* Returns the hasNextPage. W G r\R
*/ u)]sJ1p
publicboolean getHasNextPage(){ 5Cka."bQ
return hasNextPage; &b8D'XQu
} J%B?YO,
zQfxw?~A
/** Io X9yGq
* @param hasNextPage BV:,bS
* The hasNextPage to set. j !n> d
*/ +Z0E?,Oz
publicvoid setHasNextPage(boolean hasNextPage){ ~m&oa@*=y
this.hasNextPage = hasNextPage; 3<E$m*
} v@SrEmg
[cs8/Q8+
/** @(?d0xCg
* @return -^"?a]B
* Returns the hasPrePage. ?q&mI* j!
*/ 'F~SNIay
publicboolean getHasPrePage(){ @= 9y5r
return hasPrePage; 64s;6=
} rqo<Xt`
$^ 3 f}IzA
/** v> PHn69PU
* @param hasPrePage m,q<R1
* The hasPrePage to set. bv];Gk*Z-
*/ >p:fWQ6
publicvoid setHasPrePage(boolean hasPrePage){ h"S/D[
this.hasPrePage = hasPrePage; $QnfpM%+=
} 0P
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yln.E vJjD
/** E:OeU_\
* @return Returns the totalPage. AtYYu
* )$g/PQ
*/ }PuO$
L
publicint getTotalPage(){ :AGQkJb
return totalPage; Im#$iPIvT
} 4 l(o{{
*r3vTgo$
/** y~ LVK8
* @param totalPage y>PbYjuIU
* The totalPage to set. vBXr[XoC
*/
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publicvoid setTotalPage(int totalPage){ ,' B=eY,
this.totalPage = totalPage; gC 4#!P
} (k45k/PAP
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} r&RSQHa)
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J6P
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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 ;hDr+&J|
rJwJ5U
个PageUtil,负责对Page对象进行构造: [X]o`
java代码: t]XJq
UkKpSL}Q2
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/*Created on 2005-4-14*/ v_h{_b8
package org.flyware.util.page; ?sE21m?b-
gV BV@v!W
import org.apache.commons.logging.Log; 5Bk
import org.apache.commons.logging.LogFactory; ;wZ.p"T9^
AR^Di`n!
/** v2R:=d
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* @author Joa 6 [E"
* ^u{$$.&
*/ _A*0K,F-
publicclass PageUtil { SF7
Scd
v<W++X7z
privatestaticfinal Log logger = LogFactory.getLog ;<H2N0qJ(
/.bwwj_;
(PageUtil.class); ;GSj}Nq
eNb =`
/** -`&;3
7
* Use the origin page to create a new page iYkNtqn/
* @param page ^`THV
* @param totalRecords cyyFIJj]
* @return [E1I?hfJ
*/ g^FH[(P[G
publicstatic Page createPage(Page page, int u)-l+U.
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totalRecords){ AaVlNjB
return createPage(page.getEveryPage(), M-hnBt
r9[J3t*({~
page.getCurrentPage(), totalRecords); g;T`~
} pz+#1=b]
?*=Jq
/** 7
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* the basic page utils not including exception C.O-iBVe#
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handler uQCS%|8C
* @param everyPage ]LjW,b"
* @param currentPage Re_.<_$
* @param totalRecords t|%ul6{gz
* @return page PH.v3
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*/ Zlhr0itf
publicstatic Page createPage(int everyPage, int aoN[mV'
l]gfT&
currentPage, int totalRecords){ sXA=KD8
everyPage = getEveryPage(everyPage); -L@=j
currentPage = getCurrentPage(currentPage); zuw6YY8kQ
int beginIndex = getBeginIndex(everyPage, :O2N'vl47A
:M16ijkx
currentPage); q=U=Y
n
int totalPage = getTotalPage(everyPage, Sj\8$QIXC
ryPzq}#
totalRecords); L`6`NYR
boolean hasNextPage = hasNextPage(currentPage, Wp $\>
*&s_u)b
totalPage); FsjblB3?E
boolean hasPrePage = hasPrePage(currentPage); &>SE9w/?o
r.[k D"l
returnnew Page(hasPrePage, hasNextPage, \oyr[so(i
everyPage, totalPage, Zr3KzY9
currentPage, HXX"B,N
TD<. :ul]
beginIndex); 3 }XS|Y
} t V</x0#
}I"^WCyH
privatestaticint getEveryPage(int everyPage){ (Q&Z/Fe
return everyPage == 0 ? 10 : everyPage; kq+L63fZ
} HUH=Y;
;IyQqP#,<
privatestaticint getCurrentPage(int currentPage){ wXe.zLQ
return currentPage == 0 ? 1 : currentPage; CKK8 o9W
} Y&nY]VV
:|bPr_&U$
privatestaticint getBeginIndex(int everyPage, int {>#Ya;E
*:iFhKFU
currentPage){ JdE=!~\8
return(currentPage - 1) * everyPage; R/=yS7@{)
} zrcSPh
9"[#\TW9Vb
privatestaticint getTotalPage(int everyPage, int hq|/XBd||
^VD14V3
totalRecords){ ;-59#S&?tB
int totalPage = 0; 2]|+.9B
sNWj+T
if(totalRecords % everyPage == 0) /}Max@.`
totalPage = totalRecords / everyPage; k#
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else kjH0u$n
totalPage = totalRecords / everyPage + 1 ; rRxqV?>n!
\7RP6o
return totalPage; 'Q# KjY
} ]. eGsh2
V<b"jCXI
privatestaticboolean hasPrePage(int currentPage){ >5\rU[H>
return currentPage == 1 ? false : true; j:g/[_0s
} "Mth<%i
'j|;M
privatestaticboolean hasNextPage(int currentPage, MOXDR
8D-g%Aj-
int totalPage){ =73wngw
return currentPage == totalPage || totalPage == uXXwMc<p
|,o!O39}>
0 ? false : true; c}QjKJ-c
} Vx'_fb?wap
C+_ NG
_("{fJ,A
} o`G@Je_}x
f -bVcWI
Xcb\N
{C
[7V{4(%
[!"u&iu`
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 C Z|R-ky6p
KdUmetx1
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 bx1'
o}<}zTU
做法如下: R ~#\gMs
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 f5AK@]4G
AkGCIn3
的信息,和一个结果集List: 9k1n-po
java代码: %A04'dj`zQ
.- {B
ACs?m\$Q
/*Created on 2005-6-13*/ dAR):ZKq?
package com.adt.bo; [E+#+-n7
1N2s[ \q$
import java.util.List; : -OHD#>%
bEbnZ<kz*
import org.flyware.util.page.Page; m3 ,i{
`zF=h#i
/** k \|Hd"T
* @author Joa ~)ls.NXI
*/ Pn0V{SJOJ%
publicclass Result { B+ +:7!
.Gw;]s3
private Page page; 't]=ps
lf&g *%?1
private List content; ygh*oVHO
+v/_R{ M
/** 9 u{#S}c`
* The default constructor ~!\n
*/ lj(}{O
public Result(){ Z':}ZXy]
super(); -
3kg,=HU;
} 4Y[tx]<
:beBiO
/** #7GbG\
* The constructor using fields |,|b~>
* 3DbS\jja
* @param page S
7RB`I5
* @param content 6s@'z<Ct
*/ GHfsq|*j,Z
public Result(Page page, List content){ UT%^!@u
this.page = page; 7*`cWT_X
this.content = content; 5\lOZYHX
} mJp)nF8r~
<GT&q <4w
/** -:&qNY:Vp
* @return Returns the content. /aP4'U8ov
*/ W&qE_r
publicList getContent(){ %&0_0BU
return content; CNQ>J`4
} yc?+L;fN
C[z5&
x2
/** t[|^[%i
* @return Returns the page. q3n(Z
*/ Hn+w1v&3
public Page getPage(){ rfku]A$
return page; ?*){%eE
} dX?8@uzu
Q)#+S(TG
/** lku}I4
* @param content `C9/=
* The content to set. eJlTCXeZ|
*/ 3!ZndWSHV
public void setContent(List content){ bd_&=VLTC
this.content = content; 0j@gC0xu)|
} <KlG#7M>
eX;C.[&7;8
/** CvS}U%
* @param page Z(k7&^d
* The page to set. )OpB\k
*/ d ]R&mp|'
publicvoid setPage(Page page){ wGr5V!
this.page = page; Wz',>&a
} DEM;)-D
} * EY^t=
;Sl]8IZ
[oqb@J2
=^#^Mq)
b;A(6^V
2. 编写业务逻辑接口,并实现它(UserManager, u czOSd
'7Q5"M'
UserManagerImpl) z]:{ruvH
java代码: PZ06
_
KsZd.Rf=@
j+YA/54`
/*Created on 2005-7-15*/ ,e<(8@BBL
package com.adt.service; @
W[LA<
8&+m5xS
import net.sf.hibernate.HibernateException; sTv;Ogs.
%iMRJ}8(7
import org.flyware.util.page.Page; jzt$
aAJ'0xnj
import com.adt.bo.Result; JO{Rth
WCJ$S\#
/** QU{|S.\
* @author Joa w eu3c`-a
*/ 9=D09@A%e
publicinterface UserManager { X} <p|P+
>,;,
6|S
public Result listUser(Page page)throws F-0 |&0
/a@gE^TM
HibernateException; jG~zpZh
Y_S>S(0
} t|XQFb@}
fR]%:'2k
(nL''#Ka
@'XxMO[Z!<
z86[_l:
java代码: :jo
!Yi
9OI&De5?=V
b9FfDDOq"
/*Created on 2005-7-15*/ /1OzX'5f
package com.adt.service.impl; JzI/kH~
l.gt+e
import java.util.List; c0}* $e
=GGt:3Kx-
import net.sf.hibernate.HibernateException; oVDqX=G
?2LRMh")$
import org.flyware.util.page.Page; *|97 g*G(
import org.flyware.util.page.PageUtil; n^kszIu~
N!RkV\:X
import com.adt.bo.Result; V)Oj6nD]
import com.adt.dao.UserDAO; eksYIQZ]
import com.adt.exception.ObjectNotFoundException; {[Sd[P
import com.adt.service.UserManager; m 3k}iIU7
~Q4 emgBD
/** [3&Y* W
* @author Joa DSb/+8KT
*/ 'Ll,HgU;
publicclass UserManagerImpl implements UserManager { 6h8fzqRzc
L&*/s&>b
private UserDAO userDAO; sA!,)'6
BM6 J
/** AiMD"7
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* @param userDAO The userDAO to set. E}&Z=+v}
*/ F^knlv'
publicvoid setUserDAO(UserDAO userDAO){ kWkAfzf4a
this.userDAO = userDAO; YTWlR]Tr6?
} ~x}/>-d
>'\cNM~nf
/* (non-Javadoc) mI;#Zq_j
* @see com.adt.service.UserManager#listUser X0IXj%\N
IG}`~% Z
(org.flyware.util.page.Page) iobL6SUZ
*/ 5 *w
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public Result listUser(Page page)throws KaRdO
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HibernateException, ObjectNotFoundException { OanH G
int totalRecords = userDAO.getUserCount(); S4qj}`$
Yv
if(totalRecords == 0) F%<hng%k
throw new ObjectNotFoundException $]H^?
Hjho!np
("userNotExist"); y}TiN!M
page = PageUtil.createPage(page, totalRecords); {i}z|'!
List users = userDAO.getUserByPage(page); R['k&jyi
returnnew Result(page, users); JYQ.Y!X1O
} 7x,c)QES`
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} qJ\tc\
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kB`t_`7f
P[|FK(l
^g[,}t:/d
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 / /ty]j
#+X|,0p
询,接下来编写UserDAO的代码: 2d%j6D
3. UserDAO 和 UserDAOImpl: IIn0w2:i
java代码: 1O<Gg<<,e
f{]eb1
Km)5;BQxg
/*Created on 2005-7-15*/ $m$tfa-
package com.adt.dao; =e<;B_~.
y1zNF$<q
import java.util.List; W`$D*X0*o
|(mr&7O
import org.flyware.util.page.Page; -]!m4xvK
v7;zce/~
import net.sf.hibernate.HibernateException; ,}9 G|$
*)PCPYB^
/** (6Ssk4
* @author Joa *Ey5F/N}$H
*/ ,(%?j]_P2
publicinterface UserDAO extends BaseDAO { <4caG2~q
m~upTQz
publicList getUserByName(String name)throws 8|\0\Wd;vu
%D::$,;<<
HibernateException; ^iWcuh_n
}8+rrzMUB
publicint getUserCount()throws HibernateException; kPh;SCr{
R`7v3{
publicList getUserByPage(Page page)throws CA0SH{PdW&
J2c.J/o
HibernateException; /U|>
a{?`yO/ 2
} mY}_9rTn|
+Xb )bfN
dMcCSwYh
bzI!;P1&
zvvF9
java代码: tcovMn'
Cfizh@<
xjm|ewo
/*Created on 2005-7-15*/ |7ga9
package com.adt.dao.impl; aY/msplC
$~#N1
import java.util.List; 994
)X8?m <cG
import org.flyware.util.page.Page; =44hI86
vcsrI8+
import net.sf.hibernate.HibernateException; xB&kxW.;
import net.sf.hibernate.Query; mp^;8??;
@uIY+_E40g
import com.adt.dao.UserDAO; lq4vX^S
Lk%u(duU^
/** 6$]p;}#
* @author Joa _h@s)"
*/ Hh/Z4`&yi
public class UserDAOImpl extends BaseDAOHibernateImpl 5if4eitS
]6W;~w%
implements UserDAO { F vJJpPS
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/* (non-Javadoc) Fv[. %tW
* @see com.adt.dao.UserDAO#getUserByName <tT*.nM\
-3YsrcJi
(java.lang.String) |sM#nhxK
*/ f87>ul!*
publicList getUserByName(String name)throws 'rT@r:6fn
=Mg/m'QI
HibernateException { S6.N)7y
String querySentence = "FROM user in class o6@Hj+,,
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com.adt.po.User WHERE user.name=:name"; n+5X*~D
Query query = getSession().createQuery Ol;}+?[Q
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(querySentence); W*'gqwM&
query.setParameter("name", name); b4_"dg~gK
return query.list(); =:fFu,+{
}
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O2W EA
/* (non-Javadoc) ?[[K6v}q{
* @see com.adt.dao.UserDAO#getUserCount() 4JF8S#8B
*/ Ri,8rf0u
publicint getUserCount()throws HibernateException { owYSR?aG
int count = 0; i.4L;(cg
String querySentence = "SELECT count(*) FROM v>vU]6l
Rp#9T?i``[
user in class com.adt.po.User"; Ivw+U-Mz
Query query = getSession().createQuery $gYy3y
mY+.(N7m
(querySentence); 'O#,;n
count = ((Integer)query.iterate().next eRlJ
n&?]GyQ
()).intValue(); J- %YmUc)
return count; GJ >vL
} .x$!Rc}
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/* (non-Javadoc) 4:!KtpR[O
* @see com.adt.dao.UserDAO#getUserByPage #8N9@
3@k;"pFa<
(org.flyware.util.page.Page) *fBI),bZa
*/ 91oIx W
publicList getUserByPage(Page page)throws V^qZ~US
Vt_NvPB`
HibernateException { F8q &v"
String querySentence = "FROM user in class O*af`J{
-j%!p^2j9
com.adt.po.User"; ]jWe']T
Query query = getSession().createQuery R/H?/
` r; .
(querySentence); l8n}&zX
query.setFirstResult(page.getBeginIndex()) Z%*_kk
.setMaxResults(page.getEveryPage()); (n&Hjz,Fv
return query.list(); b"Hg4i)
} O5PCR6U
AHws5#;$6*
} G0sg\]
F,CQAgx
h[()!\vBy
.Gq)@{o>
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至此,一个完整的分页程序完成。前台的只需要调用 "RuH"~o
tS2 P|fl
userManager.listUser(page)即可得到一个Page对象和结果集对象 ]xf
lfZ
7y",%WYSD
的综合体,而传入的参数page对象则可以由前台传入,如果用 MSPzOJQPy
YW@Ad
webwork,甚至可以直接在配置文件中指定。 jWb;Xk4
2?LZW14$d
下面给出一个webwork调用示例: 6&% c
java代码: *Z7W'-
aHKv*-z-
u1yc
/*Created on 2005-6-17*/ $CaF"5}?Ke
package com.adt.action.user; =G*rfV@__V
YQ>M&lnQ<
import java.util.List; iMnp `:*
B7qm;(?X&
import org.apache.commons.logging.Log; M%f96XUM
import org.apache.commons.logging.LogFactory;
Y_&D W4
import org.flyware.util.page.Page; [wAI;=.
^ N]u
import com.adt.bo.Result; ya]CxnKR3
import com.adt.service.UserService; H"4^
import com.opensymphony.xwork.Action; [Q,E(
s
#$(F&>pj
/** wy&s~lpV,7
* @author Joa 3O<:eS~
*/ ]zHUF!a*
publicclass ListUser implementsAction{ lz X0B&:
I%(`2rD8G
privatestaticfinal Log logger = LogFactory.getLog W:{1R&$l
Wa~'p+<c~b
(ListUser.class); z.{T`Pn
W?8 |h
private UserService userService; RE`XyS0Q
[QA@XBy6
private Page page; #KZ6S9>@
F+Og8^!
privateList users; l>)0OP]
A P><l@
/* djV^A
* (non-Javadoc) uWR\#D'
* D`3m%O(?
* @see com.opensymphony.xwork.Action#execute() W:8_S%~d
*/ kpi)uGvGUA
publicString execute()throwsException{ YC4S,fY`
Result result = userService.listUser(page); cYyv
iR59#
page = result.getPage(); n=
yT%V.l
users = result.getContent(); T1?fC)
return SUCCESS; {ScilT
} t_c;4iE
vMKmHq
/** bb[.Kvq5
* @return Returns the page. /g2( <
*/ r-'(_t~FT
public Page getPage(){ r>4.{\C
return page; l'T3RC,\
} # 4_'%~-e
j K?GB
/** `s(T(l
* @return Returns the users. %CJgJ,pk>
*/ Ko9"mHNB
publicList getUsers(){ O]RP ?'vO
return users; ECqcK~h#E
} w+gA3Dg
5mdn77F_
/** ENm\1
* @param page xM}lX(V!w
* The page to set. <Hl.MS
*/ ST1PSuC~
publicvoid setPage(Page page){ Au,xIe!t
this.page = page; J4!Om&\@
} jdiFb~5R
B'>(kZYMs
/** Q9=vgOW+
* @param users ),y{.n:wm
* The users to set. / 2>\Z (
*/ znv2:
publicvoid setUsers(List users){ XNkw9*IT
this.users = users; W*iPseXq
} x0B|CO
;o }pRC
/** @SeE,<
* @param userService ?it49
* The userService to set. 4^(u6tX5|+
*/ n Bv|5$w:
publicvoid setUserService(UserService userService){ F-g(Hk|v
this.userService = userService; 833KU_ N
} 0G?0 Bo
} /H&:
)MqF~[k<-
B]~#+rMK
`G>
6
cN_e0;*Ua
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, \xJTsdd
/Ps}IW
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 ujsJ;\c
'|Dm\cy
么只需要: VXlTA>a }
java代码: bSsX)wHm
]@_M)[ x
A$vCm
<?xml version="1.0"?> I_N(e|s\U
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork fvccut;K
7JNhCOBB
1.0//EN" "http://www.opensymphony.com/xwork/xwork- W#!![JDc
-I4-K%%B`
1.0.dtd"> LyR to
?LAKH$t
<xwork> G>f-w F6
7@al)G;~
<package name="user" extends="webwork- MFO}E!9`q
&o*/6X
interceptors"> Vvu+gP'z.
A7SBm`XJ)p
<!-- The default interceptor stack name 1V(tt{
;=.VKW%U
--> E&r*[;$
<default-interceptor-ref v]+,kbT
}
_Yk.@J5
name="myDefaultWebStack"/> {tn%HK">
e.9oB<Etp
<action name="listUser" l}B,SkP^
$$8xdv#
class="com.adt.action.user.ListUser"> Q| >
\{M
<param |Z}uN!Jm
z17
name="page.everyPage">10</param> | W:JI
<result `~Nd4EA)2
Cc^`M9dP
name="success">/user/user_list.jsp</result> [X[d`@rXv
</action> xb$eFiQ
)TV4OT#
</package> zn|~{9>y
JK0L&t<
</xwork> &A>Hq/Y
&z;F'>"
Cn4o^6? "
44axOk!G[/
6(
TG/J
e(E6 t_
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 >!:uVS
. _JM3o}F
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 b6BeOR*ps
* Zb-YA
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 PK^{WF}L;
':6!f
|KFRC)g
}ybveZxv5A
/=co/}i
我写的一个用于分页的类,用了泛型了,hoho .z7%74p
$8#zPJR&
java代码: BhC.#u/
v~i/e+.h>y
F/;uN5{o
package com.intokr.util; VE{[52
]F
kLtq
import java.util.List; J5PXmL
!uoU 8Ki9
/** tEP~`$9
* 用于分页的类<br> ta\AiHm
* 可以用于传递查询的结果也可以用于传送查询的参数<br> A+i|zo5p=k
* z$OKn#%T
* @version 0.01 :X7"fX
* @author cheng "i/ l'
*/ P}B{FIpNG
public class Paginator<E> { z45
7/zO
privateint count = 0; // 总记录数 E'qGK T
privateint p = 1; // 页编号 `?)ivy>\:
privateint num = 20; // 每页的记录数 |f+|OZY
privateList<E> results = null; // 结果 #=r:;,,
$w{!}U 2+-
/** u2crL5^z2)
* 结果总数 E _d^&{j
*/ -m*IpDi
publicint getCount(){ R B7?T5G
return count; 92g#QZs&W
} ?g*#ld()
3B| ?{U~
publicvoid setCount(int count){ s"5f5Cn/Wh
this.count = count; Xk=bb267
} ]A)`I
kGbtZ} W
/** d%tF~|#A%
* 本结果所在的页码,从1开始 K^0cL%dB
* KICy!
"af
* @return Returns the pageNo. !.>TF+]
*/ Q
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publicint getP(){ LPr34BK
return p; R$qp3I
} D90m..\w
[_W#8{
/** p^1s9CM%
* if(p<=0) p=1 /.!ytHw8
* o'nju.'
* @param p owYf1=G
*/ +dd\_\
publicvoid setP(int p){ {.=4;
if(p <= 0) R:49Gn:F
p = 1; HmxA2 ~C
this.p = p; $RA8U:Q!1e
} Nm;(M=
Hrb67a%b
/** w7d(|`
* 每页记录数量 CMk0(sztU_
*/ Y"J'
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publicint getNum(){ q)S70M_1
return num; x;d*?69f]
} UuDs
[k)xn3[
/** AWkXWl}
* if(num<1) num=1 dN'2;X
*/ Jo%5 NXts4
publicvoid setNum(int num){ .~J}80a/
if(num < 1) dUAZDoLi
num = 1; :oRR1k
this.num = num; 8^bc4(H
} 7RW5U'B
Ww8<f$
/** %mLQ'$
* 获得总页数 bvVEV
*/ dg#w/}}m
publicint getPageNum(){ 3/+r*lv>X
return(count - 1) / num + 1; qfF/X"#0
} ')]K&
NCm>iEeY
/** xw2dEvjgp%
* 获得本页的开始编号,为 (p-1)*num+1 ;+pS-Zb
6
*/ N>8pA)
publicint getStart(){ Z4+S4cqnh
return(p - 1) * num + 1; ce3w0UeV
} cWG>w6FI
VRr_s:CWK
/** $#|iKi<Y@j
* @return Returns the results. R+}x#
*/ \^=Wp'5R
publicList<E> getResults(){ or2BG&W
return results; px `o.%`'
} 9ure:Dko(Y
j,@N0~D5
public void setResults(List<E> results){ []opPQ
1
this.results = results; Vaj4p""\F
} a~#MMl
ci]IH]x
public String toString(){ 6$42-a%b
StringBuilder buff = new StringBuilder Mlr]-Gu5Z
>cVEr+r9t
(); | g o jb
buff.append("{"); g.3 .
C?
buff.append("count:").append(count); xc|pl!ns
buff.append(",p:").append(p); \_H-TbU8
buff.append(",nump:").append(num); XQI.z7F
buff.append(",results:").append lHg&|S&J
H)#HK!F6f
(results); 1Q$ePo
buff.append("}"); TQ-V61<5
return buff.toString(); L`$m<9w'
} J$Huzs#
pVuJ4+`
} }d<xbL!#
p.Y
=
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