Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 j:0(=H!#
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 t6W$t
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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 aq@/sMn
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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 I&,gCZ#
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。 /\q1,}M
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分页支持类: 0R z'#O32V
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java代码: 7Y"CeU-S
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package com.javaeye.common.util; fo;Ftf0
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import java.util.List; f5.rzrU
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publicclass PaginationSupport { @doo2qqIe]
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publicfinalstaticint PAGESIZE = 30; j-e/nZR@
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privateint pageSize = PAGESIZE; @8a1a3_F
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privateList items; Yx>y(Whu.
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privateint totalCount; ;-Fr^|do y
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privateint[] indexes = newint[0]; ^@5#jS2
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privateint startIndex = 0;
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public PaginationSupport(List items, int U>PF#@ C/
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totalCount){ O4H %x
setPageSize(PAGESIZE); g).k+
setTotalCount(totalCount); c
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setItems(items); |wW_Z!fL
setStartIndex(0); %P05k
} =
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public PaginationSupport(List items, int MDI[TNYG
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totalCount, int startIndex){ eJD!dGa
setPageSize(PAGESIZE); C QO gR GW
setTotalCount(totalCount); T"ors]eI
setItems(items); _o'_ z ]
setStartIndex(startIndex); 2O}UVp>
} >5G2!Ns'
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public PaginationSupport(List items, int f~nAJ+m=
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); ~{MmUp rS
setTotalCount(totalCount); rWk4)+Tk
setItems(items); :"BZK5{8
setStartIndex(startIndex); eF)vx{s
} %{'hpT~h
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publicList getItems(){ ,#;%ILF4%
return items; k\,01Y^
} 0{u31#0j
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publicvoid setItems(List items){ J`F][ A
this.items = items; 57:Wh=x
} D4jf%7X!Lu
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publicint getPageSize(){ &Z
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return pageSize; F^Q[P4>m\
} n- cEa/g
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publicvoid setPageSize(int pageSize){ uYk4qorA
this.pageSize = pageSize; doJ\7c5uU
} ^ 'jJ~U
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publicint getTotalCount(){ SVvR]T&_
return totalCount; M+Rxt.~6
} P=ARttT`(
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publicvoid setTotalCount(int totalCount){ q r12"H
if(totalCount > 0){ P(N$U^pj
this.totalCount = totalCount; ]A*v\Qy
int count = totalCount / Q=hf,/N
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pageSize; e[D'0L
if(totalCount % pageSize > 0) Vj.5b0/(
count++; ;1`NsYI2
indexes = newint[count]; rw*#ta
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for(int i = 0; i < count; i++){ @WuB&uF=d
indexes = pageSize * =1D* JU
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} v 6{qKpU#
}else{ r{~K8!=oU]
this.totalCount = 0; -QaS/WO_
} 2+G_Y>
} =\IcUY,4
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publicint[] getIndexes(){ *.ffyBI*~
return indexes; WFBg3#p
} 8.vPh
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publicvoid setIndexes(int[] indexes){ .MO"8}]8Z
this.indexes = indexes; 5p&&EA/
} m4:b?[
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publicint getStartIndex(){ h 9V9.'
return startIndex; r>lC(x\B
} 1a{~B#
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publicvoid setStartIndex(int startIndex){ 64s9Dy@%F
if(totalCount <= 0) Gq5)>'D?
this.startIndex = 0; |L{<=NNs:D
elseif(startIndex >= totalCount) rn1FCJ<;H
this.startIndex = indexes {rr
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[indexes.length - 1]; L4SvE^2+
elseif(startIndex < 0) &,':@OQ
this.startIndex = 0; [.P~-6~
else{ Fs:l"5~>1
this.startIndex = indexes [|~X~AO%
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[startIndex / pageSize]; vO" $Xw
} ]4@z.1Mr
} [_j.pMH/P
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publicint getNextIndex(){ _-g:T
int nextIndex = getStartIndex() + &G55<tRE
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pageSize; lfR"22t
if(nextIndex >= totalCount) {rOz[E9vm
return getStartIndex(); nLkC-+$tM
else D00rO4~6D%
return nextIndex; F!{N4X>%T
} :i*JlKHJd
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publicint getPreviousIndex(){ FQi"OZHq
int previousIndex = getStartIndex() - I_xJ[ALdm
*cTN5S>
pageSize; -tx)7KV-
if(previousIndex < 0) fE)+9!
return0; )@Xdr0
else #.}Su+XF
return previousIndex; I}Q3B3Byg
} D]b5*_CT
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} f%*-PW^*
: M0LAN
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抽象业务类 ycw'>W3.*
java代码: ZH:#~Zyj
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/** e5fJN)+a
* Created on 2005-7-12 !l6B_[!@
*/ >E"FoZM=
package com.javaeye.common.business; |#5JI#,vX
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import java.io.Serializable; v}[KVwse
import java.util.List; xNxIqq<k
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import org.hibernate.Criteria; @b!fs
import org.hibernate.HibernateException; WF-imI:EK
import org.hibernate.Session; RWTv,pLK
import org.hibernate.criterion.DetachedCriteria; hPFIf>%}
import org.hibernate.criterion.Projections; w/G5I )G
import s'\"%~nF<
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org.springframework.orm.hibernate3.HibernateCallback; ~>}BDsM
import AH=6xtS-
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org.springframework.orm.hibernate3.support.HibernateDaoS XfbkK )d
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upport; ['-ln)96.
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import com.javaeye.common.util.PaginationSupport; W,Dr2$V
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public abstract class AbstractManager extends ~,':PUkiV
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HibernateDaoSupport { 8Qu].nKe
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privateboolean cacheQueries = false; S2jo@bp!
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privateString queryCacheRegion; gWgK
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publicvoid setCacheQueries(boolean BzWmV.5
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cacheQueries){
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this.cacheQueries = cacheQueries; _IpW&
} (2qo9j"j/Y
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publicvoid setQueryCacheRegion(String o]Vx6
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queryCacheRegion){ >+oQxml6nI
this.queryCacheRegion = 9@D,ZSi
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queryCacheRegion; j-{WPJa4\
} 8-8=
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publicvoid save(finalObject entity){ L**!$k"{5
getHibernateTemplate().save(entity); I[t)V*L9
} Vi#(x9.
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publicvoid persist(finalObject entity){ v/yk T9@;
getHibernateTemplate().save(entity); /.WD'*H
} gn(n</\/O
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publicvoid update(finalObject entity){ Nt/*VYUn
getHibernateTemplate().update(entity); HM[BFF[;/
} kFk+TXLDIt
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publicvoid delete(finalObject entity){ RNvtgZ}k{X
getHibernateTemplate().delete(entity); de ](l687I
} pd X9G
dwx1EdJ{
publicObject load(finalClass entity, 9,,v0tE
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finalSerializable id){ .Uih|h
return getHibernateTemplate().load >656if O
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(entity, id); T,?^J-h^
} T
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publicObject get(finalClass entity, ,sLV6DM
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finalSerializable id){ SH}O?d\Q:
return getHibernateTemplate().get Y}f%/vus
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(entity, id); =
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} L
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publicList findAll(finalClass entity){ EKoCm)}d
return getHibernateTemplate().find("from NU
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" + entity.getName()); ?=4J
} *jW$AH
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publicList findByNamedQuery(finalString -@#AQ\
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namedQuery){ Q6vkqu5!=
return getHibernateTemplate 5Vvy:<.la
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().findByNamedQuery(namedQuery); s@3!G+ -}
} sHEISNj/^
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publicList findByNamedQuery(finalString query, sk],_ l<
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finalObject parameter){ eN jC.w9
return getHibernateTemplate 9CL&tpqv
f
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().findByNamedQuery(query, parameter); 1^$Io}o:S
} e94csTh=
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publicList findByNamedQuery(finalString query, 7`WK1_rR\
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finalObject[] parameters){ St(7@)gvY
return getHibernateTemplate s}HTxY;
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().findByNamedQuery(query, parameters); v.Q)Obyn
} TAGqRYgi
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publicList find(finalString query){ >)VrbPRuA
return getHibernateTemplate().find 2&Efqy8}DZ
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(query); !A<?nz
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} wPG3Ap8L
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publicList find(finalString query, finalObject Crey}A/N
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parameter){ p6ZKyi
return getHibernateTemplate().find .Wa6?r<g
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(query, parameter); isDr|g$S
} Ig9$ PP+3
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public PaginationSupport findPageByCriteria L:%h]-
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(final DetachedCriteria detachedCriteria){ thq(tK7
return findPageByCriteria %_/_klxnO
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 4lz9z>J.V
} 2 K`
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public PaginationSupport findPageByCriteria :/1WJG:!
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(final DetachedCriteria detachedCriteria, finalint 7qnw.7p
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startIndex){ p_mP'
return findPageByCriteria O"{NHNG\oT
pG|DT ?
(detachedCriteria, PaginationSupport.PAGESIZE, 1g|H8CA
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startIndex); fHe3 :a5+W
} 7ZJYT#>b
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public PaginationSupport findPageByCriteria $osDw1C
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(final DetachedCriteria detachedCriteria, finalint 3tgct <"
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pageSize, -o=qYkyLK
finalint startIndex){ 1o.]"~0:
return(PaginationSupport) = [:ruE
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getHibernateTemplate().execute(new HibernateCallback(){ >pn?~
publicObject doInHibernate [Si`pPvl
.+ _x|?'
(Session session)throws HibernateException { xe_c`%_
Criteria criteria = %)]{*#N4
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detachedCriteria.getExecutableCriteria(session); n.Ekpq\
int totalCount = ,@GI3bl
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((Integer) criteria.setProjection(Projections.rowCount V}Oxz04
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()).uniqueResult()).intValue(); LnM+,cBz
criteria.setProjection E*k=8$Y
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(null); CbwQ'c$}
List items = C~kw{g+|
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criteria.setFirstResult(startIndex).setMaxResults Z(CzU{7c
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(pageSize).list(); ky[FNgQ3n
PaginationSupport ps = P PmE.%_
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new PaginationSupport(items, totalCount, pageSize, 0~"{z>s '
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startIndex); y/
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return ps; hoPCbjkov
} 2}hEBw68
}, true); w 8T#~Dc
} 91[(K'=&
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public List findAllByCriteria(final BK6oW3wD/
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DetachedCriteria detachedCriteria){ Lw2EA 5
return(List) getHibernateTemplate dTS7l02
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().execute(new HibernateCallback(){ 1[mX_ }K
publicObject doInHibernate n{=vP`V_
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(Session session)throws HibernateException { <Y<%=`
Criteria criteria = ".~,(*
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detachedCriteria.getExecutableCriteria(session); k${25*M!3
return criteria.list(); )g+~"&Gcx
} 1@;Dn'
}, true); "){"{~
} P;][i| x
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public int getCountByCriteria(final
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DetachedCriteria detachedCriteria){ ioz4kG!
Integer count = (Integer) r m\]
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getHibernateTemplate().execute(new HibernateCallback(){ PkMN@JS
publicObject doInHibernate `Z0FQ( r_
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(Session session)throws HibernateException { "! m6U#^
Criteria criteria = $CRu?WUS]'
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detachedCriteria.getExecutableCriteria(session); q\/ph(HF
return 'HzF/RKh
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criteria.setProjection(Projections.rowCount V*}ft@GPD
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()).uniqueResult(); ,F!zZNW9
} Z<@0~t_:?p
}, true); J>TNyVaoQ
return count.intValue(); J<yt/V]
} o7;lR?
} mA@FJK_
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用户在web层构造查询条件detachedCriteria,和可选的 SFv'qDA
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 |6v
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PaginationSupport的实例ps。 s'b 4Me
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ps.getItems()得到已分页好的结果集 _(l?gj
ps.getIndexes()得到分页索引的数组 L7;8:^ v
ps.getTotalCount()得到总结果数 m}hEi
ps.getStartIndex()当前分页索引 ^CO{86V
ps.getNextIndex()下一页索引 c#(Hh{0
ps.getPreviousIndex()上一页索引 J2adG+=
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Swa0TiT(
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 6I2`oag
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一下代码重构了。 `Y O(C<r-
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我把原本我的做法也提供出来供大家讨论吧: :e1kpQ
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首先,为了实现分页查询,我封装了一个Page类: 2[j(C
java代码: /9ctmW1!<
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/*Created on 2005-4-14*/ v|\3FEu@
package org.flyware.util.page; aKjP{Z0k$
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/** O,6Wdw3+-3
* @author Joa MH=7(15R
* P q0%oz
*/ .V4-
publicclass Page { (Zg'])
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/** imply if the page has previous page */ v{d$DZUs
privateboolean hasPrePage; Ps!umV
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/** imply if the page has next page */ J0V`sK
privateboolean hasNextPage; k/P.[5
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/** the number of every page */ 3xg9D.A
privateint everyPage; qv& Bai[
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/** the total page number */ ])}a^]0q
privateint totalPage; m??Py"1y
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/** the number of current page */ L!>nl4O>`
privateint currentPage; m _cRK}>
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/** the begin index of the records by the current CP~mKmMV
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query */ Ve2{;`t
privateint beginIndex; jp_|pC'
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/** The default constructor */ />Q}0Hg
public Page(){ \yl|*h3
@-}*cQ4u?
} {j=`
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/** construct the page by everyPage Z\?2"4H
* @param everyPage l+[:Cni
* */ LH)XD[
public Page(int everyPage){ I)tiXcJw
this.everyPage = everyPage; ]?pQu '-(
} S=(<m%f
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/** The whole constructor */ vfc:ok 1
public Page(boolean hasPrePage, boolean hasNextPage, H1I^Vij
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int everyPage, int totalPage, _Ao$)Gu)
int currentPage, int beginIndex){ l|=4FIMD
this.hasPrePage = hasPrePage; +LF#XS@
this.hasNextPage = hasNextPage; w8XCU>
|
this.everyPage = everyPage; In?=$_p
this.totalPage = totalPage; ;I&VpAPx
this.currentPage = currentPage; 3w</B-|nQ
this.beginIndex = beginIndex; ; h\T7pwwb
} ;xZjt4M1
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/** 6$6QAW0+f
* @return ;eN
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* Returns the beginIndex. &W,jR|B
*/ yEq7ueJ'
publicint getBeginIndex(){ TG%B:^Yz!
return beginIndex;
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} T1]?E]m{
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/** V&w2pp0
* @param beginIndex %WgN+A0
* The beginIndex to set. OvtE)ul@
*/ d=/0A\O
publicvoid setBeginIndex(int beginIndex){ J0?kEr
this.beginIndex = beginIndex; |M7cB$y
} qx t0Jr8
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/** z5kAf~A
* @return $iu[-my_
* Returns the currentPage. .!x&d4;,q
*/ fbNzRXw
publicint getCurrentPage(){ !R=@Nr>
return currentPage; Ot2o=^Ng
} } o%^
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/** MKl0 d
* @param currentPage TxX =(7V
* The currentPage to set. s_'&_>D
*/ rZ~w_DK*
publicvoid setCurrentPage(int currentPage){ flsejj$
this.currentPage = currentPage; )h8}{*
} bC/":+s& p
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/** ,~1"50 Hp@
* @return d9K8[Q5^3
* Returns the everyPage. qhEv6Yxfw6
*/ FQ]/c#J
publicint getEveryPage(){ zaqX};b
return everyPage; xG9Sk
} ,%M[$S'
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/** Rff F:,b
* @param everyPage wDJ`#"5p{
* The everyPage to set. ']r8q %
*/ pk :P;\
publicvoid setEveryPage(int everyPage){ UFG_ZoD+
this.everyPage = everyPage; uu9M}]mDl
} # ]7Lieh[5
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/** ;2p+i/sVj
* @return tAdE<).!
* Returns the hasNextPage. ,#K/+T
*/ n0xGIq
publicboolean getHasNextPage(){ Oynb"T&8
return hasNextPage; `*C=R
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} +$h
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/** R4m{D
* @param hasNextPage 5*AXL.2ih
* The hasNextPage to set. Zt `Tg7m
*/ 4:`D3
publicvoid setHasNextPage(boolean hasNextPage){ \^x{NV@v42
this.hasNextPage = hasNextPage; $ik*!om5
} P {TJ$
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/** 8xAV[i
* @return Mo,&h?VOM?
* Returns the hasPrePage. U1[)e D`
*/ Lo%n{*if
publicboolean getHasPrePage(){ WYw#mSp
return hasPrePage; lW+mH=
} -(qRC0V
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/** 6b2UPI7m~
* @param hasPrePage }LzBo\
* The hasPrePage to set. W>K^55'
*/ $x0SWJ \G
publicvoid setHasPrePage(boolean hasPrePage){ A,}M ^$@
this.hasPrePage = hasPrePage; o).deP
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} B5b:znW2@
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/** h>-P /
* @return Returns the totalPage. TNX9Z)=>g
* H iyg1
*/ (|gQ
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publicint getTotalPage(){ )@PnpC%H
return totalPage; L, JQ\!c
} =!q%
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/** #9vC]Gm
* @param totalPage Shm> r@C?
* The totalPage to set. /^.|m3
*/ KZm&sk=QM-
publicvoid setTotalPage(int totalPage){ _yg_?GH
this.totalPage = totalPage; ^L[:DB{Z
} 2jsbg{QS#_
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} +iVEA(0&$
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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_FM 2K7!
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个PageUtil,负责对Page对象进行构造: }^
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java代码: &m5zd$6
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/*Created on 2005-4-14*/ )!T~l(g
package org.flyware.util.page; ex3Qbr
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import org.apache.commons.logging.Log; *rxr:y#Ve
import org.apache.commons.logging.LogFactory; 5/meH[R\M
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/** ZN[<=w&(cB
* @author Joa \br!77
* Ey6R/M)?:y
*/ !l:GrT8J
publicclass PageUtil { 9d(\/
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privatestaticfinal Log logger = LogFactory.getLog
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(PageUtil.class); 9U8M|W|d
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/** %uW=kr
* Use the origin page to create a new page gP^2GnjHL8
* @param page Dg&84,bv^
* @param totalRecords jLVJ+mu
* @return 7_0p& 3
*/ |)-kUu
publicstatic Page createPage(Page page, int j8Z, :op
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totalRecords){ Q$jEmmm%V[
return createPage(page.getEveryPage(), +7Ws`qhEe
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page.getCurrentPage(), totalRecords); Sg#XcTG
} G7Nw}cVJ)
/ 3A6xPOg
/** Z8$}Rpo
* the basic page utils not including exception n 8cA8<
v2T2/y%
handler lC i{v.
* @param everyPage mU'<:gL+
* @param currentPage .~z'm$s1o
* @param totalRecords 9shfy4?k
* @return page ]WT@&F
*/ s**<=M GK
publicstatic Page createPage(int everyPage, int 36d nS>4
j\>LJai"
currentPage, int totalRecords){ .l}Ap7@
everyPage = getEveryPage(everyPage); H4/wO
currentPage = getCurrentPage(currentPage); nl@an!z
int beginIndex = getBeginIndex(everyPage, |Uh8b %
#&3,T1i`
currentPage); rp Nb.
int totalPage = getTotalPage(everyPage, .`or^`X3
TpjiKM
totalRecords); m]p{]6h
boolean hasNextPage = hasNextPage(currentPage, Q*ITs!~Z
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totalPage); K$E3RB_F
boolean hasPrePage = hasPrePage(currentPage); N&9o 1_}
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returnnew Page(hasPrePage, hasNextPage, !avol/*
everyPage, totalPage, bO~y=Pa\
currentPage, eP{srP3 9
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beginIndex); ^-o{3Q(w
} /:dLqyQ_V
}nmlN
privatestaticint getEveryPage(int everyPage){ 2YD\KXDo
return everyPage == 0 ? 10 : everyPage; iFI74COam
}
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t],a1I.gk
privatestaticint getCurrentPage(int currentPage){ <_?zln:4.
return currentPage == 0 ? 1 : currentPage; j,IRUx13f
} !MbzFs~
[%W'd9`>
privatestaticint getBeginIndex(int everyPage, int 86&M Zdv6
KK|w30\f
currentPage){ 1wSAwpz
return(currentPage - 1) * everyPage; \Z{tC$|H
} uvys>]+
iP:i6U]
privatestaticint getTotalPage(int everyPage, int |vI*S5kn6A
KE?t?p
totalRecords){ ,'L>:pF3
int totalPage = 0; PyeNu3Il4
6[bopin
if(totalRecords % everyPage == 0) JWVV?~1
totalPage = totalRecords / everyPage; h~dQ5%
else
)p&g!qA
totalPage = totalRecords / everyPage + 1 ; ^FCXcn9
:X2_#qW#C
return totalPage;
}{0}$#zu
} F72#vS
j
So%X(,
|
privatestaticboolean hasPrePage(int currentPage){ fN vQ.;
return currentPage == 1 ? false : true; RTtKf i}
} =lacfPS
?%kgfw@)
privatestaticboolean hasNextPage(int currentPage, yD[d%w
Cq5.gkS<
int totalPage){ ,@$5,rNf
return currentPage == totalPage || totalPage == g[xoS\d
0uy'Py@2<
0 ? false : true; # :+Nr
} 4jT6h9%
/2^L;#
"2%z;!U1
} ?0qVyK_1
s 6Wp"V(
BR|!ya+_2
so))J`ca)
u=`H n-(
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 .1QGNW
,0'GHQWz$
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 %G?@Hye3
d3%qYL_+a
做法如下: Y,L`WeQY.
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 4P{|H
srS!X$cec
的信息,和一个结果集List: A|biOz
java代码: .:_'l)-
3@Ndn
nnlj#
/*Created on 2005-6-13*/ Z[O
hZ 9
package com.adt.bo; eqtZU\GI>
HcRw9,I'
import java.util.List; FvT&nb{
&1\/B
import org.flyware.util.page.Page; ,GOIg|51
rFzNdiY
/** hY}Q|-|
* @author Joa M1jT+
*/ kD#T_d
publicclass Result { VoCg,gow
'h$:~C
private Page page; }i9:k kfq2
XQ1]F{?/H
private List content; 18$d-[hX
H3wJ5-q(
/** \p^V~fy7rU
* The default constructor NKY|Z\
*/ n6Oz[7M
public Result(){ QO@86{u#Y
super(); g{&5a(W&`
} 5Fy dh0.
@ZEBtM%.O
/** =DwLNyjU4
* The constructor using fields N^
+q^iW
* 082}=Tsx
* @param page Xj, %t}
* @param content 7i5B=y7b
*/ P"c@V,.
public Result(Page page, List content){ `IN!#b+Eo
this.page = page; ?K$&|w%{3
this.content = content; FNGa4
} WcmX"{
^y,h0?Z9
/** [;m@A\F
* @return Returns the content. TX)W.2u=
*/ dv+Gv7&2/
publicList getContent(){ x,nl PU
return content; LhG\)>Y%
} {S0-y
av'DyNW\
/** ~[=<Os
* @return Returns the page. S1|5+PPs
*/ $f@YQN=
public Page getPage(){ ?N4FB*x
return page; .!q_jl%U
} coCT]<
}u#3 hYa
/** Jp jHbG
* @param content L|1,/h
8p
* The content to set. ,#;hI{E
*/ MkW=sD_
public void setContent(List content){ V 7,dx@J-
this.content = content; Gf8 ^nfr
} 2:
QT`e&
MKbcJZe
/** 628iN%[-
* @param page NV5qF/<M
* The page to set. #cQ5-R-1
*/ (iKJ~bJ
publicvoid setPage(Page page){ <zCWLj3
this.page = page; 6B]=\H
} |!FQQ(1b
} l/3=o}8q
G=y~)B}
}NDl~5
GVhqNy
KHx2$*E_
2. 编写业务逻辑接口,并实现它(UserManager, cs6oD!h
ti61&)(
UserManagerImpl) vom3C9o
java代码: #ss/mvc3
?|,:;^2l1
H+*3e&
/*Created on 2005-7-15*/ 6uD<E
package com.adt.service; 4dixHpq'
:]:)c8!6
import net.sf.hibernate.HibernateException; ;_\yg)X,
Hn >VPz+I
import org.flyware.util.page.Page; =%8 yEb*5#
[~Ky{:@)[
import com.adt.bo.Result; #^$_/Q#C
]RAh['u|
/** 1IoW}yT
* @author Joa _1[Wv?
*/ A~xw:[zy$a
publicinterface UserManager { B*_K}5UO
gaN/
kp
public Result listUser(Page page)throws uD/@d'd_4L
z5gVP8*z5
HibernateException; ]Ea-MeH
# fqrZ9:@
} xHt7/8wF
4Q !A w
m 3UK`~ji
M|c_P)7ym
uZ8-?
java代码: ~QSX 1w"
e?XFtIj$
"BsK'yo.
/*Created on 2005-7-15*/ ^g4Gw6q6
package com.adt.service.impl; PVg<Ovi^d
' pgPQM<
import java.util.List; ZBDF>u@
='jT
5Mg
import net.sf.hibernate.HibernateException; ~AjPa}@ f
]AQ}_dRi=
import org.flyware.util.page.Page; fY^CIb$Y
import org.flyware.util.page.PageUtil; M(L6PyEa!Y
U;/2\Ii
import com.adt.bo.Result; QM8Ic,QFvo
import com.adt.dao.UserDAO; R*vQvO%)h
import com.adt.exception.ObjectNotFoundException; ,c"J[$i$
import com.adt.service.UserManager; =/K)hI!u
H.ZF~Yuw
/** T1qbb*
* @author Joa XB7*S*"!
*/ 46]BRL2 G
publicclass UserManagerImpl implements UserManager { |&"aZ!Kn
^"O>EY':
private UserDAO userDAO; ^R:&c;&,
=Rx4ZqTI|
/** O:#YLmbCN
* @param userDAO The userDAO to set. rJGh3%
*/ pl%!AY'oE>
publicvoid setUserDAO(UserDAO userDAO){ <y8oYe_!
this.userDAO = userDAO; Tr_gc~
} ^2}HF/
Ho&:Zs
/* (non-Javadoc) f2[R2sto@
* @see com.adt.service.UserManager#listUser q{`1[R
M?YNK]
(org.flyware.util.page.Page) ="78#Wfj2
*/ MO$yst?fK
public Result listUser(Page page)throws }$z(?b
Eu' ;f_s
HibernateException, ObjectNotFoundException { ]7}!3 m
int totalRecords = userDAO.getUserCount(); ~-Kx^3(#
if(totalRecords == 0) n
6pJ]Ce
throw new ObjectNotFoundException 9;Z{++z
1q(Qr
h
("userNotExist"); 3F]Dh^IR9
page = PageUtil.createPage(page, totalRecords); #&T O(bk
List users = userDAO.getUserByPage(page); k Nc-@B
returnnew Result(page, users); rX)&U4#[m
} v4hrS\M
3N$@K"qM#
} "LlQl3"=
&(,\~
ewd
eC
mH\zSk
i#>t<g`l
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ^85Eveu
Soq#cl'll-
询,接下来编写UserDAO的代码: <qfAW?tF
3. UserDAO 和 UserDAOImpl: %W9R08`
java代码: l,l qhq\
\{`^Q+<
qK7:[\T|?T
/*Created on 2005-7-15*/ .Pj<Pe
package com.adt.dao; !O%!A<3
%:'G={G`QH
import java.util.List; ('J@GTe@xj
aC`>~uX##V
import org.flyware.util.page.Page; k*?T^<c3
D&pn@6bB
import net.sf.hibernate.HibernateException; @Pk<3.S0
B>c$AS\5y
/** {,JO}Dmu5
* @author Joa Mq<ob+
*/ ;Tnid7:S
publicinterface UserDAO extends BaseDAO { `$Rgn3
HghdTs
publicList getUserByName(String name)throws jz_Y|"{`v
^P@:CBO
HibernateException; 'UhHcMh:
Fn.JtIu
publicint getUserCount()throws HibernateException; ;+XrCy!.)L
J@:Q(
publicList getUserByPage(Page page)throws B?i#m^S
WfaMu|
L
HibernateException; 9[zxq`qT}+
A0Nx?
} *gH]R*Q[Rt
pDlrK&;\z
BL 1KM2]
'>t&fzD0
iH4LZ
java代码: iV/I909*''
JD#q6&|
F8Ety^9>9
/*Created on 2005-7-15*/ "6\5eFN;
package com.adt.dao.impl; z.8 nYL5^}
WGn=3(4
import java.util.List; .f J8
N-QS/*C.~
import org.flyware.util.page.Page; Qpv#&nfUi6
B zS4:e<
import net.sf.hibernate.HibernateException; E;CM"Y*
import net.sf.hibernate.Query; qZ^
PC-
0\:=KIY.
import com.adt.dao.UserDAO; <z\SKR[
fYjmG[4
/** Qz(2Iu{E]
* @author Joa c+3`hVV
*/ TiI /I`A
public class UserDAOImpl extends BaseDAOHibernateImpl l SdA7
8^}/T#l
implements UserDAO { E#+2)Q
RJ@79L*#
/* (non-Javadoc) ?)-6~p 4N
* @see com.adt.dao.UserDAO#getUserByName Mc.{I"c@
j%s,%#al
(java.lang.String) @$r[$D
v
*/ **%&|9He
publicList getUserByName(String name)throws $x'jf?zs!
pL1ABvBB
HibernateException { Rb:H3zh
String querySentence = "FROM user in class x3cjyu<K
r%f Q$q>
com.adt.po.User WHERE user.name=:name"; zA9q`ePS
Query query = getSession().createQuery :|s;2Y
C33Jzn's
(querySentence); GP c
B(
query.setParameter("name", name); Kg';[G\
return query.list(); l%2VA
} fX`u"`o5
bUS:c
2"
/* (non-Javadoc) Oq~{HJ{
* @see com.adt.dao.UserDAO#getUserCount() Qw2`@P8W
*/ Gw3+TvwU+Q
publicint getUserCount()throws HibernateException { QIMd`c
int count = 0; -+@N/d5
String querySentence = "SELECT count(*) FROM n7bVL#Sq[
9JP:wE~y
user in class com.adt.po.User"; X1(ds*'Kv
Query query = getSession().createQuery Gt#r$.]W?o
y\^zxG*]'
(querySentence); bK%F_v3'
count = ((Integer)query.iterate().next [<f2h-V$
*fc8M(]&d
()).intValue(); yZ6WbI8n
return count; n{!{,s
} 39 }e
}W"
,;}
/* (non-Javadoc) Pg T3E
* @see com.adt.dao.UserDAO#getUserByPage +pqbl*W;1
s 1M-(d Q
(org.flyware.util.page.Page) 8<;.
*/ zK~8@{l}_"
publicList getUserByPage(Page page)throws .zZfP+Q]8
gGvL6Fu
HibernateException { qY8; k
#
String querySentence = "FROM user in class m+'1c}n^7
-lJ|x>PG'
com.adt.po.User"; A^,ul>!
Query query = getSession().createQuery ,JdBVt
XA#qBxp/h
(querySentence); Xw9]WJc
query.setFirstResult(page.getBeginIndex()) 5V/&4$.U!
.setMaxResults(page.getEveryPage()); Z0Sqw
return query.list(); Z~Q5<A9Jz
} 1R8tR#l
!O"2)RU1
} :;Z/$M16B
\@Cz 32wg
0J'^<GTL
sZ=!*tb-
0x~+=GUN
至此,一个完整的分页程序完成。前台的只需要调用 o(e(|k
{
_'cB<9P
userManager.listUser(page)即可得到一个Page对象和结果集对象 ppIXS(
'Grej8
的综合体,而传入的参数page对象则可以由前台传入,如果用 .)tQ&2
xMk>r1Ud
webwork,甚至可以直接在配置文件中指定。 c\ZI
5&4jT
X[?fU&
下面给出一个webwork调用示例: }Y7P2W+4?
java代码: _qPKdGoM
]zj#X\
7fypUQ:y
/*Created on 2005-6-17*/ W^3 Jg2gE
package com.adt.action.user; \"ogQnmz
0"e["q{|
import java.util.List; p+iNi4y@
9`92
>
import org.apache.commons.logging.Log; VE]TT><
import org.apache.commons.logging.LogFactory; #L!`n)J"
import org.flyware.util.page.Page; Ec<33i]h*p
UucX1%
import com.adt.bo.Result; &V+_b$
import com.adt.service.UserService; $&.(7F^D
import com.opensymphony.xwork.Action; RDSC @3%
l7T?Yx j
/** SVVE b6&
* @author Joa ?wkT=mv
*/ G!VEV3zT
publicclass ListUser implementsAction{ W>!:K^8]
dn'|~zf.
privatestaticfinal Log logger = LogFactory.getLog Sm {Sq
ugN%8N
(ListUser.class); 02EX_tt),
<[ dt2)%L>
private UserService userService; " TCJT390
h(kPf]0
private Page page; wclj9&k
k+[oYd
privateList users; J1(SL~e],
~c v|,
/* +vJ}'uR3P
* (non-Javadoc) g
\S6>LG!
* F\&wFA'J
* @see com.opensymphony.xwork.Action#execute() N>EMVUVS
*/ ='.b/]! _
publicString execute()throwsException{ 0
J"g"=
Result result = userService.listUser(page); u `w w
page = result.getPage(); l$!ExXEZO;
users = result.getContent(); V"8Go;[
return SUCCESS; &&$*MHJ
}
3-{WFnA
b&E"r*i|
/** 9?sY!gXc
* @return Returns the page. dCn9]cj/
*/ n\Lsm
public Page getPage(){ T] H'l
return page; 8)iI=,T*
} hy#nK:B
MA9E??p3\
/** %ho?KU2j
* @return Returns the users. 19R~&E's
*/ &to~#.qc
publicList getUsers(){ U7U&^s6`
return users; 1h`F*:nva
} fif'ptK
a'HHUii=
/** <~ay4JY
* @param page U43U2/^
* The page to set. `yl|NL
*/ {TJ"O
publicvoid setPage(Page page){ TPx0LDk%(
this.page = page; SefF Ci%4
} B:i$
;L76V$&
/** #(}{*dR
* @param users FDF DB
* The users to set. x/]G"?Uix
*/ 6E^m*la%
publicvoid setUsers(List users){ (oCpQDab@
this.users = users; 8rJf2zL
} ORX<ZOt1
Z8h;3Ek
/** MsIaMW _
* @param userService bly `mp8#
* The userService to set. 3LQu+EsS
*/ ?^:5`
publicvoid setUserService(UserService userService){ :Id8N~g
this.userService = userService; [KGj70|~
} \{*`-Pv
} g|^U?|;p
mV}8s]29
;x_T*} CH
to_dNJbv
FN26f*/
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, X/%!p<}:'
9^sz,auB
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 /3Y"F"`M.
~_CZ1
么只需要: HYdt3GtJ?
java代码: ZBK)rmhMx
@~=d4Wj6
LkF*$
<?xml version="1.0"?> 'SE5sB
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork N6\m*j,`
S_AN.8T
1.0//EN" "http://www.opensymphony.com/xwork/xwork- rx#GrV*y
phA{jJy?
1.0.dtd"> /&=y_%VR
FD~uUZTM
<xwork> ~t*_
AKLFUk
<package name="user" extends="webwork- Y!c7P,cZ+3
`}
'o2oZnG
interceptors"> %dd B$(
1,P2}mYv
<!-- The default interceptor stack name &F0>V o
P
2x.rukT|
--> xOxyz6B\
<default-interceptor-ref +:C.G[+
Qdc#v\B
name="myDefaultWebStack"/> h|z59h&X8G
+*qTZIXj
<action name="listUser" Y,4?>:39J
K.? S,qg
class="com.adt.action.user.ListUser"> %gqu7}'
<param ?$\sMkn
s<C66z
name="page.everyPage">10</param> p)Ht =~
<result Ba%b]vp
`ST;";7!
name="success">/user/user_list.jsp</result> N4yQ,tG>aa
</action> LmR OG-9
C91'dM
</package> R6o07.]
&oVZ2.O#(
</xwork> k^UrFl
^D
{v L
>I/~)B`jhE
bC&xN@4
d$MewDWUN
\rbvlO?}
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 8Sf}z@~]
!r*JGv=
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 L_zB/(h
.,p@ee$q
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 'A/{7*,
Co<F<eXe
B]#iZ,Tp
51s 3hX$
dlV HyCW
我写的一个用于分页的类,用了泛型了,hoho y.Yni*xt/
!1+!;R@&H>
java代码: Pf<BQ*n
n3hlo@gYW
>hotkMX `3
package com.intokr.util; }"^d<dvuz
c<)O#i@3/
import java.util.List; C !Lu`y
w^ 8^0i-
/** f1Gyl
* 用于分页的类<br> gEq";B%?
* 可以用于传递查询的结果也可以用于传送查询的参数<br> l2
#^}-
* >lK:~~1
* @version 0.01 Y-"7R>^I
* @author cheng q+67Wc=
*/ g.Kyfs4`
public class Paginator<E> { !xC IvKW
privateint count = 0; // 总记录数 c=:A/z{
privateint p = 1; // 页编号 PtKrks|y
privateint num = 20; // 每页的记录数 A$J?-
privateList<E> results = null; // 结果 v kW2&
2s`~<EF N
/** n#5 pd;!n
* 结果总数 "4QD\k5
*/ `uqsYY`V
publicint getCount(){ G"prq&
return count; RjHKFB2
} Z9I
?j1K|!
.|J-(J<>[.
publicvoid setCount(int count){ >D$NEO^
this.count = count; ozG!OiRW
} M|'![]-
==W] 1@s
/** [iG4qI
* 本结果所在的页码,从1开始 9D& 22hL4
* {F$MZ2 E
* @return Returns the pageNo. G c:oSvm
*/ &G!2T!xx
publicint getP(){ ].*I Z
return p; 9Or
} l:"zYcp%
5sF?0P;ln
/** x4S0C[k
* if(p<=0) p=1 l`<u\],
* OD1>s6uA7
* @param p sJ cwN.s
*/ -*"Q-GO
publicvoid setP(int p){ E{Y)=tW[
if(p <= 0) *}N J
p = 1; ]`n6H[6O
this.p = p; m"8Gh`Fo
} GH6ozWA
}?z_sNrDk
/** 2/G`ej!*
* 每页记录数量 \}})U#
*/ vZ2/>}!Z=
publicint getNum(){ 4>8'.8S
return num; Z^vcODeC$
} iN@+,]Yjl
JlN<w
/** ' +[fJ> Le
* if(num<1) num=1 J@pCF@'
*/ 3%SwCYd
publicvoid setNum(int num){ T,Zfz9{n
if(num < 1) ye1hcQ
num = 1; "':u#UdS
this.num = num; tm280
} `!iVMTp
o;Ma)/P
/** 9"mcN3x:\e
* 获得总页数 LIDYKKDJ^
*/ hNJubTSE+)
publicint getPageNum(){ ob;$yn7ZO1
return(count - 1) / num + 1; 6(.]TEu0
} \ HZ]=B#0
Rd{#cW~
/** j; )-K 3Ia
* 获得本页的开始编号,为 (p-1)*num+1 =WP`i29j9}
*/ vL:tuEE3
publicint getStart(){ $X:r&7t+Q[
return(p - 1) * num + 1; /tGj`C&qtw
} ZQPv@6+oY
X`FFI6pb
/** v %fRq!~
* @return Returns the results. Qk.:b
*/ dKwY\)\
publicList<E> getResults(){ DU%j;`3
return results; yzQ^KqLH
} %?[H=v(b
Yhkn(k2
public void setResults(List<E> results){ {Deg1V!x>
this.results = results; kdHP
v=/U
} atO/Tp
6S2v3
public String toString(){ v"dj%75O?e
StringBuilder buff = new StringBuilder ;\Vi~2!8
/_MEb42&
();
cfEi]
buff.append("{"); 3d@$iAw1<
buff.append("count:").append(count); /_G^d1T1?L
buff.append(",p:").append(p); #RwqEZ
buff.append(",nump:").append(num); HC*V\vz
buff.append(",results:").append d,9YrwbD
)cX6o[oia
(results); X3j<HQcK
buff.append("}"); j3`"9bY
return buff.toString(); !(EJ. |LH
} gM<*(=x'
aZMMcd
} J~[A8o
dkRG4
)~g
s!d"(K9E