Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Y<S,Xr;J:
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 `jb?6;15
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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 \TrhJ
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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 YDyi6x,
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分页支持类: &4yI]
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java代码: <c6C+OWT,
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package com.javaeye.common.util; V4!RUqK
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import java.util.List; }IGr%C(3%
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publicclass PaginationSupport { x=bAR%i~
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publicfinalstaticint PAGESIZE = 30; >w?O?&Q$
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privateint pageSize = PAGESIZE; mYN|)QVKy
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privateList items; @W^A%6"j
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privateint totalCount; Oav^BhUO
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privateint[] indexes = newint[0]; D;|4ZjM-
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privateint startIndex = 0; lV^sVN Z]
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public PaginationSupport(List items, int 8_ns^6XK5p
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totalCount){ kG+CT
setPageSize(PAGESIZE); c|Nv^V*2
setTotalCount(totalCount); d3(T=9;f2
setItems(items); vGC^1AM
setStartIndex(0); #uT-_L}sw
} $_l@k=
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public PaginationSupport(List items, int Db=
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totalCount, int startIndex){ 3
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setPageSize(PAGESIZE); }{S W~yW
setTotalCount(totalCount); Mx-,:a9}
setItems(items); Vcl"qz@Fj
setStartIndex(startIndex); Fp06a!7<
} >b |l6#%
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public PaginationSupport(List items, int /"Om-DK%
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); 9QI\[lT&
setTotalCount(totalCount); ?jBna
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setItems(items);
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setStartIndex(startIndex); A[!Fg0X0
}
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publicList getItems(){ ,l`q
return items; Sz"J-3b^
} gNzQ"W=
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publicvoid setItems(List items){ kkFE9:[-c&
this.items = items; M>0=A
} ][6$$Lz
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publicint getPageSize(){ ~c`@uGw
return pageSize; ![:S~x1
} +?(2-RBd
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publicvoid setPageSize(int pageSize){ <<w $Ur
this.pageSize = pageSize; t[F tIj6
} 2:/'
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publicint getTotalCount(){ EH] 5ZZ[Z
return totalCount; (( Ec:(:c
} bUp%87<*X
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publicvoid setTotalCount(int totalCount){ co<){5zOT
if(totalCount > 0){ 7vcYI#(2
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this.totalCount = totalCount; JHc|.2Oe
int count = totalCount / @k,u xe-
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pageSize; Z.:5<oEKg
if(totalCount % pageSize > 0) Yk:fV &]
count++; 5}~*,_J2Z
indexes = newint[count]; oFHVA!lqe
for(int i = 0; i < count; i++){ 9ToM5oQ
indexes = pageSize * J~DP*}~XK
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} x-U:T.+{
}else{ *
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this.totalCount = 0; 23y7l=.b/
} djPr 4Nog
} v(=fV/
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publicint[] getIndexes(){ R',|Jf=`
return indexes; YurK@Tq7
} |I7P0JqP
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publicvoid setIndexes(int[] indexes){ xp1
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this.indexes = indexes; ?qw&H /R
} u|WX?@\
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publicint getStartIndex(){ ]NuY{T&:
return startIndex; FI*.2rdSR
} \"_;rJ{!aE
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publicvoid setStartIndex(int startIndex){ iyu%o9_0
if(totalCount <= 0) 7-w
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this.startIndex = 0; W&z.O
elseif(startIndex >= totalCount) >?b/_O
this.startIndex = indexes c"H4/,F
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[indexes.length - 1]; %6L!JN
elseif(startIndex < 0)
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this.startIndex = 0; gJ c5Y
else{ M$%aX,nk'
this.startIndex = indexes sryujb.,
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[startIndex / pageSize]; {;Mcor3
} .+ai
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} 88pz<$
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publicint getNextIndex(){ t{!}^{
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int nextIndex = getStartIndex() + emw3cQ
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pageSize; 05DK-Wh?
if(nextIndex >= totalCount) VV?+q)
return getStartIndex(); ;{q7rsE
else C
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return nextIndex; Puily9#
} }.o
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publicint getPreviousIndex(){ cm-cwPAh
int previousIndex = getStartIndex() - Si6%6rAhj
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pageSize; kd|@.
if(previousIndex < 0) xlgN}M
return0; &{x5 |$SD
else ;'}1
return previousIndex; 4rwfY<G
} @ L% 3}
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} 8cfxKUS
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抽象业务类 ]8d]nftY
java代码: zJ3{!E}`v
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/** {G%`K,T
* Created on 2005-7-12 T"in
*/
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package com.javaeye.common.business; ["MF-tQ5
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import java.io.Serializable; .9lx@6]+
import java.util.List; ]#j]yGV
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import org.hibernate.Criteria; '2uQ
import org.hibernate.HibernateException; 6}n_r}kNR
import org.hibernate.Session; i)+@'!6
import org.hibernate.criterion.DetachedCriteria; D7[ 8*^
import org.hibernate.criterion.Projections; #XQEfa
import C[& \Xq
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org.springframework.orm.hibernate3.HibernateCallback; _;v4]MU
import k/j]*~"
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org.springframework.orm.hibernate3.support.HibernateDaoS Xv]O1 f cI
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upport; 2o6KVQ
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import com.javaeye.common.util.PaginationSupport; ;5PXPpJ
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public abstract class AbstractManager extends +QtK
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HibernateDaoSupport { ~U~KUL|
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privateboolean cacheQueries = false; c[3sg
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privateString queryCacheRegion; LUHj3H
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publicvoid setCacheQueries(boolean >y(;k|-$
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cacheQueries){ &]ts*qCEL
this.cacheQueries = cacheQueries; ]6GdB3?UVM
} &Jk0SUk MP
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publicvoid setQueryCacheRegion(String Fv.}w_
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queryCacheRegion){ h-<('w:A
this.queryCacheRegion = 1bYc^(z0
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queryCacheRegion; C6M|A3^T
} crz )F"
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publicvoid save(finalObject entity){ % E3
getHibernateTemplate().save(entity); (Z,v)TOXjV
} Q\<C9%a
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publicvoid persist(finalObject entity){ :~~}|Eu
getHibernateTemplate().save(entity); c/^}
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} #i%it
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publicvoid update(finalObject entity){ u+&BR1)C
getHibernateTemplate().update(entity); 7!]$XGz[
} 0x4Xs
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publicvoid delete(finalObject entity){ #OqQD6
getHibernateTemplate().delete(entity); J LT10c3
} =$X5O&E3'
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publicObject load(finalClass entity, iyB02\d
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finalSerializable id){ FWq+'GkSV
return getHibernateTemplate().load WJ<nc+/v:
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(entity, id); sG=D(n1
} AA6_D?)vv
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publicObject get(finalClass entity, aqQ
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finalSerializable id){ f7Y0L8D
return getHibernateTemplate().get ZgP=maQk
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(entity, id); F=7X,hK
} 6NPCp/
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publicList findAll(finalClass entity){ EcxPbRg
return getHibernateTemplate().find("from <1YINkRz
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" + entity.getName()); f=+|e"i#p
} r{!]`
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publicList findByNamedQuery(finalString nsKl3}uU
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namedQuery){ 8UJK]_99I,
return getHibernateTemplate x_pS(O(C
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().findByNamedQuery(namedQuery); P^&%T?Y6z
} .vE=527g)
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publicList findByNamedQuery(finalString query, #` Q3Z}C
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finalObject parameter){ 2&MIt(\-
return getHibernateTemplate Y,w'Op
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().findByNamedQuery(query, parameter); IFcxyp
} 8n+&tBq1
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publicList findByNamedQuery(finalString query, m\o<a|
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finalObject[] parameters){ K+ZJSfO6
return getHibernateTemplate dw#K!,g
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().findByNamedQuery(query, parameters); N[~{'i
} Xb?:dlu3
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publicList find(finalString query){ dn(I$K8
return getHibernateTemplate().find H=Scrvfx
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(query); %sxLxx_x!
} ;\ ^'}S|3Z
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publicList find(finalString query, finalObject W; yNg
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parameter){ *`2.WF@E)
return getHibernateTemplate().find t5t,(^ ;f
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(query, parameter); ,cZhkXd
} l/1u>'
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public PaginationSupport findPageByCriteria Fa<>2KkOr
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(final DetachedCriteria detachedCriteria){ G&=4@pLY5
return findPageByCriteria ,)/gy)~#
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); x93h{Kf
} Zk,`
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public PaginationSupport findPageByCriteria .c__<I<G<
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(final DetachedCriteria detachedCriteria, finalint )4:K@
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startIndex){ gZA[Sq
return findPageByCriteria I|zak](HU
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(detachedCriteria, PaginationSupport.PAGESIZE, L7i2is
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startIndex); v:\8
} 4/KGrY!ck
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public PaginationSupport findPageByCriteria 4'3do>!
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(final DetachedCriteria detachedCriteria, finalint paKur%2u
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pageSize, ` 9;0Y
finalint startIndex){ ],`xd_=]=
return(PaginationSupport) 7egE."
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getHibernateTemplate().execute(new HibernateCallback(){ {
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publicObject doInHibernate ] V|hDU=t
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(Session session)throws HibernateException { -R%T Dx
Criteria criteria = J)7\k$ D
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detachedCriteria.getExecutableCriteria(session);
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int totalCount = *vy^=Yea
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((Integer) criteria.setProjection(Projections.rowCount |Gp!#D0b
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()).uniqueResult()).intValue(); /ILj}g'
criteria.setProjection OlU')0Y
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(null); )6+Z9 9w
List items = ))T@U?r
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criteria.setFirstResult(startIndex).setMaxResults D;nd_{%
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(pageSize).list(); &f=O`*I'+!
PaginationSupport ps = NS<C"O
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new PaginationSupport(items, totalCount, pageSize, vEy0DHEE
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startIndex); ATQw=w
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return ps; Borr
} iGq%|o>
}, true); FOPfob[
} F
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public List findAllByCriteria(final &}'FC7}
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DetachedCriteria detachedCriteria){ 5)5$h]Nz>
return(List) getHibernateTemplate uzoI*aqk-s
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().execute(new HibernateCallback(){ G]]"Jc
publicObject doInHibernate n!aA<
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(Session session)throws HibernateException { (@DqKB
Criteria criteria = !S.O~Kq
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detachedCriteria.getExecutableCriteria(session); ]?<
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return criteria.list(); U
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} *S xDwN
}, true); awXK9}.
} +3yG8
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public int getCountByCriteria(final N#``(a
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DetachedCriteria detachedCriteria){ M)F_$
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Integer count = (Integer) c,2OICj
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getHibernateTemplate().execute(new HibernateCallback(){ \gsJ1@
publicObject doInHibernate bO i-QD
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(Session session)throws HibernateException { Z~0TO-Q
Criteria criteria = vp32}zeD
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detachedCriteria.getExecutableCriteria(session); XF&_**0n
return `@q\R-`
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criteria.setProjection(Projections.rowCount ?gsPHP US
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()).uniqueResult(); o%b6"_~%3
} /7 8zs-
}, true); ;J@U){R
return count.intValue(); XS}-@5TI
} 216`rQ}z
} 2Z-[x9t
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用户在web层构造查询条件detachedCriteria,和可选的 i]#"@xQ
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 3PjX;U|
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PaginationSupport的实例ps。 BM~6P|&qD
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ps.getItems()得到已分页好的结果集 /1v:eoF;
ps.getIndexes()得到分页索引的数组 P BVF'~f@j
ps.getTotalCount()得到总结果数 vM@8&,;
ps.getStartIndex()当前分页索引 vX7U|zy
ps.getNextIndex()下一页索引 ?n]adS{
ps.getPreviousIndex()上一页索引 Vx}e,(i
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 AdpJ4}|0
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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 V'tqsKQ!
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一下代码重构了。 ~_hA{$
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我把原本我的做法也提供出来供大家讨论吧: c1q;
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首先,为了实现分页查询,我封装了一个Page类: EJP] E)
java代码: '6kD6o_p1
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/*Created on 2005-4-14*/ oiIl\#C
package org.flyware.util.page; VJ8'T"^Hf
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/** (j~T7og
* @author Joa ;"2VU"
* UT5xUv5'
*/ K_AdMXF9
publicclass Page { UlWm).
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o[1#)&
/** imply if the page has previous page */ +!GJ
privateboolean hasPrePage; gKY6S?
yM}3u4FG
/** imply if the page has next page */ KYZ#.f@
privateboolean hasNextPage; @tJ4^<`P{
')}itS8
/** the number of every page */ {+ Ibi{
privateint everyPage; .hM t:BMf*
E]v]fy"
/** the total page number */ /N({"G'
privateint totalPage; ySB0"bl
c^O&A\+;
/** the number of current page */ @eZBwFe
privateint currentPage; qX`Hi9ja
}VRl L>HAC
/** the begin index of the records by the current oB%_yy+
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query */ :
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privateint beginIndex; F\hVunPVx
6yBd9= 3K
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/** The default constructor */ {/(.Bpld
public Page(){ (t\U5-w
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} 6O/c%1VHA3
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*]|
/** construct the page by everyPage S8B?uU
* @param everyPage ZqdoYU'
* */ s_}6#;
public Page(int everyPage){ ZPY&q&R
this.everyPage = everyPage; >&Oql9_
} u;]xAr1
`a:3S@n(}
/** The whole constructor */ k$ T
public Page(boolean hasPrePage, boolean hasNextPage, ;Xa
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int everyPage, int totalPage, &XdTY +
int currentPage, int beginIndex){ *7-rm
this.hasPrePage = hasPrePage; '
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this.hasNextPage = hasNextPage; VM:|I~gJ
this.everyPage = everyPage; }JWkV1
this.totalPage = totalPage; o$Ylqb#
this.currentPage = currentPage; 9pPLOXr ,
this.beginIndex = beginIndex; [=BMvP5
} WF-jy7+
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/** L&y"oAp<
* @return &PH:J*?C}
* Returns the beginIndex. DRR)mQBb
*/ =E>P,"D
publicint getBeginIndex(){ zfE8=d8U
return beginIndex; >MKj~Ud
} zH Z;Y^{+
n1b:Bv4"]#
/** lz::6}
* @param beginIndex \K~wsu/?`
* The beginIndex to set. -ycdg'v
*/ |IV7g*J89
publicvoid setBeginIndex(int beginIndex){ F~qZIggD
this.beginIndex = beginIndex; Ll-QhcC$
} y 3o3 G
}#u #m.
/** rjiHP;-t1
* @return jDqG9]
* Returns the currentPage. `'^o45
*/ iF Mf[qBg
publicint getCurrentPage(){ <G|i5/|7
return currentPage; N6of$p'N
} T)OR HJ&,
xpO;V}M|
/** ;@Fb>lBhX
* @param currentPage 4p-"1 c$
* The currentPage to set. /gl8w-6
*/ 0^dYu/i5
publicvoid setCurrentPage(int currentPage){ |6b~c{bt
this.currentPage = currentPage; }% q-9
} enZZ+|h
cV0CI&
/** b}ya9tCl;
* @return >p@b$po
* Returns the everyPage. ?>7-a~*A@
*/ a*LfT<hmU3
publicint getEveryPage(){ 0+ $gR~^^
return everyPage; s2NBYDi$?
} c?EvrtND
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/** GM'yOJo
* @param everyPage Y I;iG[T,&
* The everyPage to set. Hnk&2bY
*/ aA52Li
publicvoid setEveryPage(int everyPage){ P_NF;v5v
this.everyPage = everyPage; T}=^D=
} OqDP{X:
Jy%?"wn
/** OR!W3
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* @return Fz,jnV9=j
* Returns the hasNextPage. +)WU:aKI
*/ JffaT_"\
publicboolean getHasNextPage(){ {4,],0bjx/
return hasNextPage; w(aHB8T
} ;s{'cN[.
;m#4Q6k)V?
/** prN+{N8YC
* @param hasNextPage Ikf[K%NKn
* The hasNextPage to set. w-#
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*/ L;$>SLl,
publicvoid setHasNextPage(boolean hasNextPage){ ?#xm6oe#aH
this.hasNextPage = hasNextPage; &e:+;7
} abT,"a\h
=WW5H\?
/** $.,B2} '
* @return >@Ht*h{~
* Returns the hasPrePage. qf\W,SM
*/ ?.%dQ0
publicboolean getHasPrePage(){ r>FwJm!
return hasPrePage; |,:p[Oy
} +llb{~ZN
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/** T\bP8D
* @param hasPrePage ]q{_i
* The hasPrePage to set. QCb%d'_w+
*/ uf#h~;B
publicvoid setHasPrePage(boolean hasPrePage){ )]FXUz|;
this.hasPrePage = hasPrePage; &`v?oN9$
} UAhWJ$(C
kl.; E{PL
/** ;]Q6K9.d8
* @return Returns the totalPage. bV&9>fC
* bA#9'Qu^j
*/ )V2W:M
publicint getTotalPage(){ #8"oqqYi
return totalPage; =dDPQZEin
} `s T;\
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/** /CNsGx%%
* @param totalPage ?@$xLUHR4
* The totalPage to set. .cQO?UKK
*/ Wy7w zt
publicvoid setTotalPage(int totalPage){ G/Sp/I<d
this.totalPage = totalPage; n]'
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} XyE$0i~t
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} }rfikm
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Lo!hyQ)
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个PageUtil,负责对Page对象进行构造: }u
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java代码: vJ65F6=G
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/*Created on 2005-4-14*/ &=kv69v
package org.flyware.util.page; pvyEs|f=%
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import org.apache.commons.logging.Log; dz([GP'-*
import org.apache.commons.logging.LogFactory; . &j+&
)&j`5sSXcr
/** '?veMX
* @author Joa w/nohZF6H
* %o%V4K*
*/ T{C;bf:Q
publicclass PageUtil { 3 Vc}Q'&Y
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privatestaticfinal Log logger = LogFactory.getLog r9_ ON|
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(PageUtil.class); >z\IO
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/** tjx8UgSi
* Use the origin page to create a new page hXjZ>n``
* @param page 1 6zxPSTr}
* @param totalRecords BeVDTk:
* @return <C'_:&M
*/ /"g Ryv
publicstatic Page createPage(Page page, int 80@\e
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totalRecords){ a(A~S u97
return createPage(page.getEveryPage(), /\/^= j
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page.getCurrentPage(), totalRecords); /Pg)7Zn
} r/!,((Z\
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/** R|\eBnfI
* the basic page utils not including exception hD
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d,(y$V+
handler CwX?%$S
* @param everyPage M
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* @param currentPage ;pW8a?
* @param totalRecords M[mYG _{J
* @return page |"SZpx
*/ +QFKaS<sn
publicstatic Page createPage(int everyPage, int !+PrgIp>
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currentPage, int totalRecords){ Jj
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everyPage = getEveryPage(everyPage); hUlRtt
currentPage = getCurrentPage(currentPage); Zt3sU_
int beginIndex = getBeginIndex(everyPage, a|u#w~
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currentPage); 9<_hb1'
int totalPage = getTotalPage(everyPage,
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totalRecords); aA|{r/.10K
boolean hasNextPage = hasNextPage(currentPage, %[p*6&V
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totalPage); }) -V,\
boolean hasPrePage = hasPrePage(currentPage); FTZ=u0
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returnnew Page(hasPrePage, hasNextPage, z[c8W@OJ
everyPage, totalPage, ta)gOc)r
R
currentPage, 5?>4I"ne
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beginIndex); 71nZi`AR
} f 3H uT=n
]2@(^x'=
privatestaticint getEveryPage(int everyPage){ >`x|E-X"
return everyPage == 0 ? 10 : everyPage; qIZ+%ZOu
} pWRdI_
0vqH-)}
privatestaticint getCurrentPage(int currentPage){ y$R8J:5f
return currentPage == 0 ? 1 : currentPage; 9A.NM+u7
}
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M
+OVqTsFU
privatestaticint getBeginIndex(int everyPage, int uQ W)pD{_
7He"IJ
currentPage){ FAnz0p+t
return(currentPage - 1) * everyPage; Bo"9;F
} 3%)cUkD
w PR Ns9^
privatestaticint getTotalPage(int everyPage, int LLTr+@lj
QPf\lN/$4d
totalRecords){ _;PQt" ]
int totalPage = 0; !}*vM@)1
;I*t5{
if(totalRecords % everyPage == 0) SSF:PTeG>
totalPage = totalRecords / everyPage; t08U9`w
else MM32\}Y6
totalPage = totalRecords / everyPage + 1 ; :5~Dca_iU4
1/9*c *w
return totalPage; N9/k`ZGC
} F7=9> ,
vX }iA|`#
privatestaticboolean hasPrePage(int currentPage){ ^`yhN
return currentPage == 1 ? false : true; g&g:HH:
} O<s7VHj
*/K[B(G
privatestaticboolean hasNextPage(int currentPage, 55O}S Us!P
VjWJx^ZL#
int totalPage){ i<Ms2^
return currentPage == totalPage || totalPage == !hQ-i3?qm
c/K#W$ l
0 ? false : true; e W8cI)wU
} !b`fykC
^ZsIQ4 @`
F[\T'{
} t_Eivm-,B
js"Yh
J0IKI,X.
_W(xO
|,M
Nt8"6k_
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。 \*CXXp`
c_qox
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 )$^xbC#j`3
3/vtx9D
做法如下: \/1~5mQ+
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 h{mzYy}b
H,KH}25
的信息,和一个结果集List: $CB&>?~
java代码: ByjfPb#
]B(}^N>WH
l#cVQ_^"
/*Created on 2005-6-13*/ RgoF4g+@
package com.adt.bo; *m"@*O'
L?u{v X
import java.util.List; \)28,`
auN8M.
import org.flyware.util.page.Page; =&pR=vl
DH\Ox>b=
/** GThGV"
* @author Joa ,zZH>P
*/ waC i9
publicclass Result { %.
((4 6)
;,U@zB;\%(
private Page page; ]Qe~|9I
Eo$l-Hl5=
private List content; T+XcEI6w
MMa`}wSs
/** E*)A!2rlK
* The default constructor _\4r~=`HQ
*/ _~Od G
public Result(){ aEdMZ+P.
super(); iJ58RY
} i/!{k2
xy>$^/[$
/** /w dvm4
* The constructor using fields &S.p%Qe"
* [x>Pf1
* @param page 9hK8dJw
* @param content 1<x5{/CZ
*/ e#5WX
public Result(Page page, List content){ j\KOKvY)
this.page = page; iU.` TqR7
this.content = content; u@D5SkT
} X ([^i;mr
3 a(SmM:
/** A["6dbvv
* @return Returns the content. G AH<
*/ 8Ie0L3d-
publicList getContent(){ |qpm
return content; @I Y<i5(
} nS$4[!0
TS=%iMa
/** zk70D_}L
* @return Returns the page. f(}&8~ &
*/ \W_ Dz*N
public Page getPage(){ ++w{)Io Z
return page; ~+ae68{p
} U'b}%[
LkeYzQH/l
/** xg%{p``
* @param content 6/QWzw.0c
* The content to set. hDJ+Rk@
*/ mq<:^
public void setContent(List content){ 56."&0
this.content = content; ^38kxwh
} 9&kY>M>z0
:1'1n
/** n>^9+Rx|i
* @param page d?U,}tv
* The page to set. P[`>*C\9c
*/ p^{yA"MQ
publicvoid setPage(Page page){ f3,Xb
]h
this.page = page; ViOXmK"
} 4u p7:?
} V'.gE6we
~Gg19x.#uW
`h'Ab63
%,N-M]Jf
"}uu-5]3
2. 编写业务逻辑接口,并实现它(UserManager, T?n [1%K
P'5Lu
UserManagerImpl) C>l (4*S
java代码: 7}=MVp] )S
/$8& r
UQ e1rf
/*Created on 2005-7-15*/ GYT0zMMf
package com.adt.service; y#ON=8l
;rh=63g
import net.sf.hibernate.HibernateException; i+-=I+L3
qk&BCkPT
import org.flyware.util.page.Page; 6jal5<H
yh4%
import com.adt.bo.Result; ojWf]$^y}
^*NOG\BK@
/** A?ESjMy(R
* @author Joa z1e+Ob&
*/ Mv%B#J
publicinterface UserManager { >]bS"S
}
F*=+n
public Result listUser(Page page)throws IxlPpS9Wx
huin?,eGz
HibernateException; 2JHF*zvO-
Y^?PHz'Go
} R'1"`@fG
:OaGdL
]_y;Igaj
Q|Pm8{8
Wu?[1L:x
java代码: h=cA]^:=
a'G[!"
[/cJc%{N
/*Created on 2005-7-15*/ d/?0xL W
package com.adt.service.impl; K!88 Nox(
toox`|
import java.util.List; Im`R2_(]
VDy_s8Z#
import net.sf.hibernate.HibernateException; %+$!ctn
(n{!~'3
import org.flyware.util.page.Page; /P{'nI
import org.flyware.util.page.PageUtil; 0pe*DbYP5
mc6W"
import com.adt.bo.Result; s[*I210
import com.adt.dao.UserDAO; 3V/|" R2s
import com.adt.exception.ObjectNotFoundException; y*sqnzgF
import com.adt.service.UserManager; OdJ=4 x>
tUFXx\p
/** "FfP&lF/
* @author Joa o,
qBMo^.
*/ P$A'WEO'
publicclass UserManagerImpl implements UserManager { |SsmVW$B|
MB5X$5it
private UserDAO userDAO; Of$gs-
wMiRN2\^
/** zL:k(7E
* @param userDAO The userDAO to set. %t-}dC&
*/ H`U>ZJ.
publicvoid setUserDAO(UserDAO userDAO){ 6FI`0j=~
this.userDAO = userDAO; iHOvCrp+X
} #mv~1tL
4vPKDd
/* (non-Javadoc) cT^x^%
* @see com.adt.service.UserManager#listUser B\7 80p<
t4,(W`
(org.flyware.util.page.Page) cy_zEJjbD
*/ ^t)alNGos
public Result listUser(Page page)throws O$&4{h`
k{C|{m
HibernateException, ObjectNotFoundException { )0@&pEObm
int totalRecords = userDAO.getUserCount(); w3oe.hWP3N
if(totalRecords == 0) 9O#?r82
throw new ObjectNotFoundException 8F`799[p
}KL( -Ui$
("userNotExist"); jowR!rqf
page = PageUtil.createPage(page, totalRecords); &
Mf nH
List users = userDAO.getUserByPage(page); P0szY"}
returnnew Result(page, users); QcDtZg\
} }2_i<4,L
IQ}YF]I;
} xXc3#n
ehYGw2
k'Z$#
c:z<8#A}
q0]Z` <w
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 *6*/kV?F
p[gq^5WuC
询,接下来编写UserDAO的代码: Ja6PX P]'
3. UserDAO 和 UserDAOImpl: qeZ*!H6-
java代码: ,n+~S^r
E@$HO_;&
c`G~.paY|
/*Created on 2005-7-15*/ V4
Wn
package com.adt.dao; Q" an6ht|
~f>km|Q{u
import java.util.List; FiJU
*
Jx1JtnyP@
import org.flyware.util.page.Page; c1Ta!p{%
}fKpih
import net.sf.hibernate.HibernateException; JdeGQ
s\dF7/b
/** Z}'"c9oB
* @author Joa {$mj9?n=v
*/ GT"gB$Mh
publicinterface UserDAO extends BaseDAO { 7 V+rQ
?]L:j
publicList getUserByName(String name)throws \;smH;m
j;']L}R
HibernateException; ^yB>0/{)z
U$(AZ|0
publicint getUserCount()throws HibernateException; (GdL(H#IL
e7.!=R{6
publicList getUserByPage(Page page)throws ;MR(Eaep
~?)ST?&
HibernateException; mT2Fn8yC1
PjkJsH
} c}>p"
"Q ~-C|x
z2lEHa?w
#E(
n
Ll L8Q
java代码: <ZM8*bqi
yr
/p3ys
7BhRt8FSD+
/*Created on 2005-7-15*/ h[O!kwE
package com.adt.dao.impl; oLXQ#{([
D'823,-).
import java.util.List; Y"&c .
c*g(R.!
import org.flyware.util.page.Page; ]+B#SIC;
V0h
import net.sf.hibernate.HibernateException; >@BvyZ)i
import net.sf.hibernate.Query; jpCQ2 XD:
.Lk2S "+
import com.adt.dao.UserDAO; @9pk-BB^D
wb
}W;C@
/** zV }-_u.
* @author Joa An e.sS
*/ i+V4_`
public class UserDAOImpl extends BaseDAOHibernateImpl 3wBc`vJ!
sc!
e$@U
implements UserDAO { v*nX
E30VKh |
/* (non-Javadoc) J!:ss
* @see com.adt.dao.UserDAO#getUserByName g[P8
J8x>vC
(java.lang.String) r$*p
*/ %HJ_0qg
publicList getUserByName(String name)throws N*Owfr1N
&OiJJl[9
HibernateException { DaW_-:@s
String querySentence = "FROM user in class }>w;(R
'lU9*e9
com.adt.po.User WHERE user.name=:name"; @,-xaZ[
Query query = getSession().createQuery !=.5$/
k.DDfuKN
(querySentence); U&6!2s-
query.setParameter("name", name); QMzBx*g(
return query.list(); c4R6E~S
} ^AUmIyf_
[Uezi1I
/* (non-Javadoc) pt;kN&A^
* @see com.adt.dao.UserDAO#getUserCount() Ve&(izIh
*/ @^vVou_
publicint getUserCount()throws HibernateException { X}yEMe{T
int count = 0; XY5I5H_U
String querySentence = "SELECT count(*) FROM J0}OmNTzD
RkN a;j)t
user in class com.adt.po.User"; R0M(e@H~
Query query = getSession().createQuery mB$r>G/'
;&|ja]r
(querySentence); TZq']Z)#
count = ((Integer)query.iterate().next j"E_nV:Qc
)ll`F7B-
()).intValue(); h{]l?6`
return count; i%M2(8&^Q
} ~PUz/^^
s
>sP-)ZeuU[
/* (non-Javadoc) 33\{S$p
* @see com.adt.dao.UserDAO#getUserByPage \HDRr*KO
Y>+\:O
(org.flyware.util.page.Page) Frt_X %
*/ a`CsL Bv&
publicList getUserByPage(Page page)throws PCs+`
WP!M
k[N46=u
HibernateException { 8KD7t&H
String querySentence = "FROM user in class +gTnq")wnI
c8gdY`
com.adt.po.User"; //W<\
Query query = getSession().createQuery (i7]N[
;""V s6
(querySentence); ;h3uMUCml
query.setFirstResult(page.getBeginIndex()) nVoPTr
.setMaxResults(page.getEveryPage());
_tN"<9v.
return query.list(); :JSOj@s
} m5sgcxt/
+GWeu0b(~
} -lyT8qZ:(
4.7ePbk[E
pd,5.d
kzGD*
RaAi9b[/S
至此,一个完整的分页程序完成。前台的只需要调用 C} +w<
5>7ECe*
userManager.listUser(page)即可得到一个Page对象和结果集对象 (?&X<=|"
u(?
的综合体,而传入的参数page对象则可以由前台传入,如果用 J;+iW*E:
L
'342(
webwork,甚至可以直接在配置文件中指定。 3a_S-&?X
jjkiic+tDN
下面给出一个webwork调用示例: :a}hd^;[%8
java代码: HW{osav9
LN?fw
)k3zOKZ;
/*Created on 2005-6-17*/ AMvM H
package com.adt.action.user; TC3xrE:U<m
mz[rB|v"/7
import java.util.List; w/N.#s^
G;FY2;adK
import org.apache.commons.logging.Log; q?&vV`PG5
import org.apache.commons.logging.LogFactory; Tm@mk
import org.flyware.util.page.Page; y&A*/J4P
.8l\;/o|
import com.adt.bo.Result; \Btv76*,
import com.adt.service.UserService; 5>q|c`&}E
import com.opensymphony.xwork.Action; u%#bu^4"
Z*nC
;5Kd
/** _I~W!8&w>
* @author Joa CO1D.5
*/ 1A">tgA1
publicclass ListUser implementsAction{ @Wy>4B^
o8RagSIo8
privatestaticfinal Log logger = LogFactory.getLog '>Y"s|
vj^vzFb K
(ListUser.class); ;&P%A<[`
JMw1qPJQ
private UserService userService; I1
j-Q8
R\MM2_I
private Page page; N/Z3 EF_
Dq
Kk9s;6_
privateList users; goeWZ O
Ip(
IGR"
/* S?*v p=
* (non-Javadoc) N|T%cdh:/
* qp^O\>c
* @see com.opensymphony.xwork.Action#execute() xRJv_=dT
*/ #5N#^#r"
publicString execute()throwsException{ MVH^["AeR
Result result = userService.listUser(page); d5%A64?
page = result.getPage(); "MKgU[t
users = result.getContent(); "o`N6@[w^
return SUCCESS; 8,#v7ns}#
} ;_,=
g` 6Xrf
/** _NA0$bGN9
* @return Returns the page. GrW+P[j9
*/ .#6Dad=S*
public Page getPage(){ <u*~RYA2
return page;
s6rdQI]
} M/ 0!B_(R
P8Fq %k
/** d
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* @return Returns the users. B[!wo
*/ Z'>Xn^
publicList getUsers(){ WsTbqR)W%
return users; ?7'uo$
} d90B15]gv
M&~3fRb4
/** Z[yQKy
* @param page OO]~\j
* The page to set. &p^S6h
*/ N't*e Ci
publicvoid setPage(Page page){ kz(%8qi8&
this.page = page; S`BLwnU`#
} +eZR._&0
M ZB0vdx
/** `)&-;CMY
* @param users ddmTMfH
* The users to set. z"u4t.KpL
*/ mZDrvTI'
publicvoid setUsers(List users){ [7ZFxr\:!
this.users = users; 9;k_"@A6
} l!<Nw8+U
E#`=xg
/** {^1GHU
* @param userService \Q|1I
* The userService to set. G@oY2sM"
*/ 3aQWzEnh
publicvoid setUserService(UserService userService){ :t8(w>oW
this.userService = userService; h )"PPI
} @H"~/ m_o
} :seo0w]
cXFNX<
0
ML=]
&7!&]kA+
Pk7Yq:avL
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, FRQ0tIp
G,e>dp_cPu
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 EkgS*q_
<- Q=h?D
么只需要: FylL7n
java代码: (YF`#v6
mEmznA
fmXA;^%
<?xml version="1.0"?> &/d;4Eu
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1D&Q{?RM
'^'vafs-/@
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ".O+";wk
x1W<r)A )r
1.0.dtd"> y5 $h
ZMy0iQ@
<xwork> d_BECx<\
YgNt>4K
<package name="user" extends="webwork- ^]3Y11sI
sWP5=t(i+9
interceptors"> Yj|Oy
,`v)nwP
<!-- The default interceptor stack name fHCLsI
5 e~\o}]
--> 'due'|#^
<default-interceptor-ref UM(tM9
r j#K5/df
name="myDefaultWebStack"/> vcy}ZqWBO
d>*?C!xE
<action name="listUser" 3,+)3,N
E%t_17,=j
class="com.adt.action.user.ListUser"> im_WTZz2P
<param Jiyt,D*wX
m{
.'55
name="page.everyPage">10</param> (ec?_N0=
<result abh='5H|^|
.p NWd
name="success">/user/user_list.jsp</result> <UOx >=h
</action> $73 7oV<
:^tw!U%y1
</package> j-8v$0'
M>VT$!Lx
</xwork> 0W<:3+|n4
N@lTn}U
LF vKF .
"5"6mw?
@r]wZ~@
NBuibL
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 1{i)7:Y
Kv^ez%I
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。 fNNkc[YTZI
^I=c]D]);
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 !qsk;Vk7Z
s!esk%h{K
q(4W/y
Z{s&myd
Y u\<
我写的一个用于分页的类,用了泛型了,hoho la:i!qAH
o4,fwPkB
java代码: &4Q(>"iL4
1OJD!juL$
/ PDe<p
package com.intokr.util; S
C7Tp4
rVgz+'rFD[
import java.util.List; aT1T.3 a
3e4; '5q;
/** e6f:@ O?
* 用于分页的类<br> ~G|un}g=
* 可以用于传递查询的结果也可以用于传送查询的参数<br> SN+B8*!
* qP{S!Z(
* @version 0.01 C` ?6`$Y
* @author cheng 86NAa6BW
*/ k~Qb"6n2
public class Paginator<E> { 7\m.xWX e
privateint count = 0; // 总记录数 sVtxh]
privateint p = 1; // 页编号 <`,pyvR Kv
privateint num = 20; // 每页的记录数 4A^=4"BCV
privateList<E> results = null; // 结果 !Z[dK{f"
eIBHAdU+g/
/** .|[ZEXq
* 结果总数 =r=[e}&9
*/ Pz#D9.D0
publicint getCount(){ eSo/1D
return count; [,[;'::=o4
} }6ObQa43
Rp$t;=SMD
publicvoid setCount(int count){ MF:]J
this.count = count; qI;"yG-x-
} X_GR{z%
"9,z"k
/** /cHd&i,>
* 本结果所在的页码,从1开始 [lZo'o
* d MQ]=
* @return Returns the pageNo. B7r={P!0
*/ [~03Z[_"/
publicint getP(){ M:x?I_JG8
return p; u&/[sqx
} dzJ\+
@4
H }w"4s
/** ReE-I/n8f
* if(p<=0) p=1 zK`fX
* 5N
"fD{v{
* @param p XOgl>1O
*/ V^fSrW]
publicvoid setP(int p){ 7KIOI,qb6
if(p <= 0) L".Qf|b*
p = 1; td!WgL,m
this.p = p; V
;Kzh$^rk
} ?mKj+Bk2
*#+e_)d
/** 3]xe7F'`
* 每页记录数量 0I_A$Z,x
*/ ^9*FYV
publicint getNum(){ qjcy{@ j
return num; tYV%izE
} /MFy%=0l
_=W ^#z
/** Z*
eb
* if(num<1) num=1 5sJi- ^
*/ Pw:(X0@
publicvoid setNum(int num){ "q@OMf
if(num < 1) lrSdFJ%
num = 1; {TT@Mkz_QC
this.num = num; !u~h.DrvZ
} G8xM]'y
<SM{yMz
/** 6J. [9#
* 获得总页数 AQkH3p/W
*/ ZqKUz5M4
publicint getPageNum(){ *zoAD|0N
return(count - 1) / num + 1; Fx#0
:p
} )=VSERs
K..L8#SC
/** )o!y7MTl
* 获得本页的开始编号,为 (p-1)*num+1 0{M=^96
*/ ;\(Wz5Ok&J
publicint getStart(){ 6<0-GD}M
return(p - 1) * num + 1; tI50z khaB
} r,}U-S.w
xK4b(KJj
/** 3/a$oO
* @return Returns the results. Co6ghH7T
*/ weQC9e~d{-
publicList<E> getResults(){ I)$` @.
return results; e ='bc7$
} lK;/97Ze
(?MRbX]@
public void setResults(List<E> results){ &1O[N*$e
this.results = results; Abr:UEG
} GE4d=;5
Gy{C*m7Q
public String toString(){ }'HJV B_
StringBuilder buff = new StringBuilder :%GxU;<E{
oXw} K((|
(); d"zbY\`
buff.append("{"); V0hC[Ilr
buff.append("count:").append(count); cgKK(-$ny
buff.append(",p:").append(p); ca>6r`
buff.append(",nump:").append(num); c +Pg[1-
buff.append(",results:").append `>:ozN#)\
b_88o-*/
(results); m~s.al(G91
buff.append("}"); !>XG$-$`Z
return buff.toString(); B ;Zsp
} 6itp
Mck
J/(3:
a>
} U" eP>HHp
(QQ /I;
@l3L_;6a