Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 +1y$#~dl
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ;Y^'$I2fR#
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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 O1z]d3x
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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 FzJ7 OE|
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分页支持类: ! ;t\lgMl
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java代码: m$W>~
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package com.javaeye.common.util; 4KM-$h,4O
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import java.util.List; H;1@]|sH#
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publicclass PaginationSupport { AI.(}W4]
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publicfinalstaticint PAGESIZE = 30; !#c'|
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privateint pageSize = PAGESIZE; GXtK3YAr
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privateList items; vQljxRtW
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privateint totalCount; B{nwQC b
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privateint[] indexes = newint[0]; ;miif
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privateint startIndex = 0; r=H?fTY<3E
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public PaginationSupport(List items, int J-v1"7[2GC
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totalCount){ aOwjYl[?p
setPageSize(PAGESIZE); \Oeo"|
setTotalCount(totalCount); B.q/}\
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setItems(items); Ktq 4b%{
setStartIndex(0); hx:q@[ +J/
} Re,;$_6o
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public PaginationSupport(List items, int DiFYVR<@
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totalCount, int startIndex){ %F;BL8d
setPageSize(PAGESIZE); @NL cO}
setTotalCount(totalCount); ZZY# .
setItems(items); ]M7FIDg
setStartIndex(startIndex); (~GQncqa
} C^J<qq&
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public PaginationSupport(List items, int ubcB<=xb
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totalCount, int pageSize, int startIndex){ ^65I,Z"
setPageSize(pageSize); O3} JOv_
setTotalCount(totalCount); Eomfa:WL
setItems(items); 7D6`1&
setStartIndex(startIndex); {&=+lr_h?
} }L\;W:0
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publicList getItems(){ $UR:j8C{p$
return items; !g@Ky$
} u m9yO'[C
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publicvoid setItems(List items){ _U s"
this.items = items; F]\
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} t'n@yX_
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publicint getPageSize(){ V8^la'_j
return pageSize; ~:ASv>m
} >JpBX+]5m
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publicvoid setPageSize(int pageSize){ v:t;Uk^Y
this.pageSize = pageSize; %{u@{uG0'3
} 1Bj.MQ^
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publicint getTotalCount(){ azP H~'E'
return totalCount; {^N,=m\
} u8Ys2KLpL
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publicvoid setTotalCount(int totalCount){ Qs&;MW4q
if(totalCount > 0){ G4*
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this.totalCount = totalCount; >y3FU1w5d
int count = totalCount / >q"dLZ
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pageSize; ,mHME~
if(totalCount % pageSize > 0) Y^fw37b
count++; \ruQx)5M
indexes = newint[count];
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for(int i = 0; i < count; i++){ (95|DCL
indexes = pageSize * #T=iS(i
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} {L-^J`> G
}else{ &<A,\M
this.totalCount = 0; C[J9 =!t
} -D`1z?zHra
} qSY\a\.<
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publicint[] getIndexes(){ ^O07GYF
return indexes; YYWD\Y`8
} k@4N7}
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publicvoid setIndexes(int[] indexes){ U=Ps#
this.indexes = indexes; .j]tzX
} i|eX X)$
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publicint getStartIndex(){ Na0^csPm
return startIndex; +kL7"
} aI=p_+.h
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publicvoid setStartIndex(int startIndex){ aU!}j'5Q
if(totalCount <= 0) ^ZwZze:2
this.startIndex = 0; I\l&'Q^0@
elseif(startIndex >= totalCount) V*vQNPey
this.startIndex = indexes -S sgW
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[indexes.length - 1]; *u},(4Qf
elseif(startIndex < 0) m<CrkKfpG
this.startIndex = 0; f:>y'#P
else{ 69c4bT:b"
this.startIndex = indexes ?;XO1cs
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[startIndex / pageSize]; Z@bgJL83
} -CvmZ:n
} m
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publicint getNextIndex(){ _2fW/U54_
int nextIndex = getStartIndex() + ..N6]u
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pageSize; m{IlRf'
if(nextIndex >= totalCount) zMSwU]4I!
return getStartIndex(); R{g=
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else +Mo4g2W
return nextIndex; S;~eI8gQ"
} 4Mt3<W5
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publicint getPreviousIndex(){ > Pw5!i\
int previousIndex = getStartIndex() - YVIE v
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pageSize; 1Lb)S@Q`*R
if(previousIndex < 0) vk7IqlEQ
return0; K[T0);hZR
else VVJ0?G
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return previousIndex; j7}mh
} 5rsz2;#p
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} "Bd-h|J
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抽象业务类 ^/n1hg
java代码: -P;3BHS$T
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/** Rw+r1vW:A
* Created on 2005-7-12 %]P{)*y-?
*/
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package com.javaeye.common.business; |8` }8vo)
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import java.io.Serializable; ![z2]L+TB
import java.util.List; R27'00(Z0
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import org.hibernate.Criteria; mP)bOAU
import org.hibernate.HibernateException; zyPb\/
import org.hibernate.Session; Wl| i$L)7
import org.hibernate.criterion.DetachedCriteria; w%L4O;E]*{
import org.hibernate.criterion.Projections; 7Z>vQ f B
import >CvhTrPI
ka_m
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org.springframework.orm.hibernate3.HibernateCallback; #9GfMxH
import ?`RlYu
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org.springframework.orm.hibernate3.support.HibernateDaoS d+DO}=]
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upport; j/t%7,
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import com.javaeye.common.util.PaginationSupport; "Q@m7j)(
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public abstract class AbstractManager extends k$$SbStD
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HibernateDaoSupport { kFjv'[Y1N
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privateboolean cacheQueries = false; e66Ag}Sw|
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privateString queryCacheRegion; LATizu
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publicvoid setCacheQueries(boolean Ta[2uv>
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cacheQueries){ /
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this.cacheQueries = cacheQueries; "L.k
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} B Ewa QvQ!
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publicvoid setQueryCacheRegion(String +3o
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queryCacheRegion){ xd{.\!q.
this.queryCacheRegion = |uy@v6
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queryCacheRegion; 6%V:Z
} HS|Gz3~
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publicvoid save(finalObject entity){ 1gK|n
getHibernateTemplate().save(entity); )M;~j
} 0er|QC
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publicvoid persist(finalObject entity){ dOv\]
getHibernateTemplate().save(entity); DOyO`TJi
} 18X?CoM~
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publicvoid update(finalObject entity){ '`^~Zy?c
getHibernateTemplate().update(entity); dEYw_qJ2
} O.jm{x!m
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publicvoid delete(finalObject entity){ gw)z*3]~s
getHibernateTemplate().delete(entity); bIm4s
} 2Pb+/1*ix
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publicObject load(finalClass entity, ?Tc|3U
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finalSerializable id){ DOu^
return getHibernateTemplate().load igL5nE=n
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(entity, id); +788aK,{#
}
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publicObject get(finalClass entity, 0V6, &rTF
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finalSerializable id){ o|>=<l
return getHibernateTemplate().get ="]lN
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(entity, id); ft7M9<#v
} n
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publicList findAll(finalClass entity){ :.=:N%3[
return getHibernateTemplate().find("from 4x
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], Bafz)4
" + entity.getName()); (}wPu&Is,C
} t{UVX%b
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publicList findByNamedQuery(finalString )xf(4
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namedQuery){ ,7:GLkj
return getHibernateTemplate {
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().findByNamedQuery(namedQuery); K
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} xJw"
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publicList findByNamedQuery(finalString query, >!Gq[i0
: F3UJ[V
finalObject parameter){ psvc,V_*
return getHibernateTemplate i-w<5pGnf
mvH}G8
().findByNamedQuery(query, parameter); y~*B%KnEQy
} tX%
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publicList findByNamedQuery(finalString query, _3W .:
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finalObject[] parameters){ _S[@?]=`b
return getHibernateTemplate NI"Zocp
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().findByNamedQuery(query, parameters); (]sm9PO
} *0oa2fz%
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publicList find(finalString query){ AHr^G'
return getHibernateTemplate().find /V0Put
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(query); BO}IN#
} EO(l?Fgw]$
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publicList find(finalString query, finalObject -hfDf{QN
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parameter){ %{'[S0 @Z
return getHibernateTemplate().find Z*P/ ubV'
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(query, parameter); ;~
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} mx1Bk9h%Xe
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public PaginationSupport findPageByCriteria L$a{%]I
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(final DetachedCriteria detachedCriteria){ c='W{47
return findPageByCriteria Ib2&L
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); b"@-9ke5I
} nzxHd7NIZ
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public PaginationSupport findPageByCriteria o9ys$vXt*
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(final DetachedCriteria detachedCriteria, finalint -mO<(wfV>
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startIndex){ 6(\-aH'Ol
return findPageByCriteria G~_eBy
;[lLFI
(detachedCriteria, PaginationSupport.PAGESIZE, >g+Y//Z
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startIndex); +R$;LtR
} AvIheR
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public PaginationSupport findPageByCriteria r.@UH-2c
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(final DetachedCriteria detachedCriteria, finalint =|O]X|y-lZ
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pageSize, #mioT",bm=
finalint startIndex){ b+RU <qR
return(PaginationSupport) eJ[+3Wh
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getHibernateTemplate().execute(new HibernateCallback(){ ?st}rJ_
publicObject doInHibernate %/U'Wu{*
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(Session session)throws HibernateException { Pvv7|AV
Criteria criteria = mGwJ>'+d
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detachedCriteria.getExecutableCriteria(session); R/B/|x
int totalCount = }#g &l*P
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((Integer) criteria.setProjection(Projections.rowCount 1A(f_ 0,.Q
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()).uniqueResult()).intValue(); (.z0.0W
criteria.setProjection 3?gfDJfE
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(null); B}y#AVSA
List items = ]We0 RD"+
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criteria.setFirstResult(startIndex).setMaxResults d]_].D$
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(pageSize).list(); !oRN,m[7)p
PaginationSupport ps = Pr1OQbg]8
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new PaginationSupport(items, totalCount, pageSize, M_?B*QZJI
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startIndex); I8W9Kzf
return ps; #RdcSrw)W!
} <|3F('Q"
}, true); ,
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} J| 46i
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public List findAllByCriteria(final lS2`#l >
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DetachedCriteria detachedCriteria){ _+~jZ]o
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return(List) getHibernateTemplate CJ3/8*;w
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().execute(new HibernateCallback(){ <X5V]f
publicObject doInHibernate _s=<Y^l%x
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(Session session)throws HibernateException { q` |E9
Criteria criteria = su60j^e*
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detachedCriteria.getExecutableCriteria(session); ;8]Hw a1!
return criteria.list(); vl`St$$|
} \WUCm.w6\%
}, true); *=%`f=
} /byF:iYI
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public int getCountByCriteria(final Cb|R
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DetachedCriteria detachedCriteria){ hR>`I0|p&
Integer count = (Integer) ]'#^ ~.
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getHibernateTemplate().execute(new HibernateCallback(){ 527u d^:
publicObject doInHibernate 93.L887
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(Session session)throws HibernateException { Tz(Dhb,
Criteria criteria = lP(<4mdP
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detachedCriteria.getExecutableCriteria(session); TYxi&;w
return Ej@N}r>X
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criteria.setProjection(Projections.rowCount 5tVg++I
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()).uniqueResult(); @a]`C
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} M7gqoJM'Q
}, true); m}m|(;T
return count.intValue(); {X\FS
} |z)7XK
} O4W2X@
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用户在web层构造查询条件detachedCriteria,和可选的 rsK
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 w 3L+7V,!
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PaginationSupport的实例ps。 51>OwEf<R
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ps.getItems()得到已分页好的结果集 m`,h nDp
ps.getIndexes()得到分页索引的数组 (bogAi3<F
ps.getTotalCount()得到总结果数 ZN;fDv
ps.getStartIndex()当前分页索引 ;Ac!"_N?7
ps.getNextIndex()下一页索引 zL+M-2hV
ps.getPreviousIndex()上一页索引 yA<\?Ps
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;uU 8$
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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 %B# 8
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一下代码重构了。 h`:gMhn
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我把原本我的做法也提供出来供大家讨论吧: e({-.ra
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首先,为了实现分页查询,我封装了一个Page类: 3{-
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java代码: 9\R+g5
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/*Created on 2005-4-14*/ 5lm>~J!/^
package org.flyware.util.page; qP[jtRIN
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/** ){i
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* @author Joa u+]8Sq
* s !HOrhV
*/ v}"DW?
publicclass Page { kAk+Sq^n
cfW;gFf
/** imply if the page has previous page */ k`,>52
privateboolean hasPrePage; flU?6\_UC
wb-_CQ
/** imply if the page has next page */ Cy\! H&0wg
privateboolean hasNextPage; &o)eRcwH`
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h#
/** the number of every page */ ohB@ij C!
privateint everyPage; ncij)7c)u
p w`YMk
/** the total page number */ 3gba~}c)
privateint totalPage; +C[%^G-:
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/** the number of current page */ <SNu`,/I
privateint currentPage; (yhnv Z
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/** the begin index of the records by the current `CEHl &w
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query */ 8Nf%<nUv
privateint beginIndex; /:aY)0F0<&
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/** The default constructor */ b(:U]>J
public Page(){ WQYw@M~4Q!
e[L%M:e9U
} IM~2=+
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/** construct the page by everyPage eq$.np
* @param everyPage |Skhx9};
* */ kG3m1: :
public Page(int everyPage){ Zm/I &
this.everyPage = everyPage; Gmh6|Dsg
} 2lRE+_qz
7,Q>>%/0P
/** The whole constructor */ HO9w"){d$
public Page(boolean hasPrePage, boolean hasNextPage, nHF%PH#|o
IkJ-*vI6
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int everyPage, int totalPage, 96S#Q*6+R
int currentPage, int beginIndex){ S/7?6y~
this.hasPrePage = hasPrePage; UB|}+WA3
this.hasNextPage = hasNextPage; nK9?|@S*'
this.everyPage = everyPage; o",J{
this.totalPage = totalPage; _ "H&
this.currentPage = currentPage; Ex}hk!
this.beginIndex = beginIndex; E4N{;'
} h_K!ch}
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/** Hn!13+fS
* @return <GO 5}>}p8
* Returns the beginIndex. Fhk`qh'i
*/ qO}Q4a+
publicint getBeginIndex(){ 9._owKj
return beginIndex; J'Y;j^
} !juh}q&}|
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/** ,FDRU
* @param beginIndex
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* The beginIndex to set. *'h J5{U
*/ 6~c:FsZ)
publicvoid setBeginIndex(int beginIndex){ :[.**,0R
this.beginIndex = beginIndex; 'yR)z\)
} =/MA`>
jdAjCy; s!
/** BXB ZX@jVk
* @return 7Nt6}${=z
* Returns the currentPage. [e;c)XS[
*/ zM2_z
publicint getCurrentPage(){ Q?]-/v
return currentPage; E8]kd
} k?;B1D8-n
g!DJW
/** YzVhNJWpw
* @param currentPage ![j?/376
* The currentPage to set. IcP\#zhEv
*/ &*8_ w-
publicvoid setCurrentPage(int currentPage){ 6#(==}Sm+
this.currentPage = currentPage; V(3=j)#
} 'CA{>\F$F+
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/** &Na,D7A:3I
* @return 6g&Ev'
* Returns the everyPage. u@pimRVo
*/ g}n-H4LI
publicint getEveryPage(){ db`L0JB
return everyPage; XsbYWJdds
}
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/** \2!1fN
* @param everyPage ;Bwg'ThT
* The everyPage to set. 6tF_u D
*/ m< Y I}
publicvoid setEveryPage(int everyPage){ Z]qbLxJV
this.everyPage = everyPage; 5)iOG#8qJ
} kmT5g gy
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/** pq$-s7#
* @return hU6oWm
* Returns the hasNextPage. iR]K!j2
*/ dpSNh1
publicboolean getHasNextPage(){ =bJ7!&
return hasNextPage; zy(NJ
} x7ZaI{
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/** #.j}:
* @param hasNextPage T: I34E[
* The hasNextPage to set. 7]H<ou
*/ cB=ExD.Q
publicvoid setHasNextPage(boolean hasNextPage){ b|oT!s
this.hasNextPage = hasNextPage; #gsJ
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} cPy/}A
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/** |wINb~trz
* @return qV79bK
* Returns the hasPrePage. y~n1S~5cI
*/ g+A>Bl3#
publicboolean getHasPrePage(){ O+OUcMa,
return hasPrePage; ACOn}yH
} gE: ?C2
^:~!@$*;6
/** A~}5T%qb
* @param hasPrePage ]p!)8[<
* The hasPrePage to set. QTC!vKM
*/ sOVU>tb\'
publicvoid setHasPrePage(boolean hasPrePage){ TyhO+;
this.hasPrePage = hasPrePage; 50""n7I<%
} H)+QkQb}
w)C5XX30;
/** /V
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* @return Returns the totalPage. uH]oHh!}j
* c{
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*/ rXP~k]tC
publicint getTotalPage(){ _;M3=MTM9
return totalPage; ,pIh.sk7s*
} /mXxj93UA
lFl(Sww!\
/** #/B g5:
* @param totalPage Bmt^*;WY+
* The totalPage to set. iD*L<9
*/ -}_1f[b
publicvoid setTotalPage(int totalPage){ $C{,`{=
this.totalPage = totalPage; pO92cGJ8
} nF
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} dTjDVq&Hz
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ;5DDV6
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个PageUtil,负责对Page对象进行构造: Wdi`ZE
java代码: tI)|y?q
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/*Created on 2005-4-14*/ Al=ByX @
package org.flyware.util.page; B"8jEYT5
t)1`^W}
import org.apache.commons.logging.Log; 1yVhO2`7]
import org.apache.commons.logging.LogFactory; MU%7'J :_
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/** "}V_.I*+
* @author Joa IC?(F]$%>
* u*/+cT
*/ uP+VS>b
publicclass PageUtil { PMUW<UI
*YSRZvD<\
privatestaticfinal Log logger = LogFactory.getLog jD${ZIv
SA7(EJ95
(PageUtil.class); `/^
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/** P?S]Q19Q4
* Use the origin page to create a new page 5vg="@O K
* @param page (zh[1[a
* @param totalRecords tva=DS
* @return NBHpM}1xtU
*/ C~R
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publicstatic Page createPage(Page page, int f,4erTBH
. P+Qu
totalRecords){ MqJ5|C.q
return createPage(page.getEveryPage(), t1]/Bw`j/
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page.getCurrentPage(), totalRecords);
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} #*:^\z_Jd
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/** Qe{w)e0}`
* the basic page utils not including exception `XpQR=IOMb
8CZ%-}-%$
handler k/D{&(F ~
* @param everyPage 5'c#pm\Q
* @param currentPage 4Y$\QZO
* @param totalRecords 5C&*PJ~WA
* @return page 4hODpIF
*/ SiUu**zC
publicstatic Page createPage(int everyPage, int yOt#6Vw
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currentPage, int totalRecords){ Qn,6s%n
everyPage = getEveryPage(everyPage); _&/ {A|n
currentPage = getCurrentPage(currentPage); a6-.|tt#t
int beginIndex = getBeginIndex(everyPage, r0 )ne|&Hp
9h?'zyX
B
currentPage); f:-l}Zj
int totalPage = getTotalPage(everyPage, Zskj?+1
-58q6yA
totalRecords); 9 @xl{S-
boolean hasNextPage = hasNextPage(currentPage, z}B39L
Mx$&{.LFJ
totalPage); ?*%_:fB
boolean hasPrePage = hasPrePage(currentPage); |/vJ+aKq
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returnnew Page(hasPrePage, hasNextPage, P.qzP/Ny
everyPage, totalPage, I{jvUYrKH
currentPage, H#DvCw
H=Ilum06
beginIndex); s<)lC;#e
} 5OppK(Oi*C
ZGDT
6,
privatestaticint getEveryPage(int everyPage){ @J"tM.
return everyPage == 0 ? 10 : everyPage; uO`MA%
z<
} >a,D8M?
c%J6!\
privatestaticint getCurrentPage(int currentPage){ JD~;.3$/k
return currentPage == 0 ? 1 : currentPage; ,_fz)@)
} 4a"Fu<q
u}gavG l
privatestaticint getBeginIndex(int everyPage, int AoeRoqg
3_~iq>l
currentPage){ >
:IWRc2
return(currentPage - 1) * everyPage; NOuG# P
} D**GC
Cq"KKuf
privatestaticint getTotalPage(int everyPage, int hU8Y&R)=9
`X}:(O^GO
totalRecords){ 0n}13u=}
int totalPage = 0; M[gL7-%w\
<"J]u@|
if(totalRecords % everyPage == 0) ]mb8R:a1
totalPage = totalRecords / everyPage; U8w_C\Q
else E5d$n*A
totalPage = totalRecords / everyPage + 1 ; *q*3SP/
$Sgf jm
return totalPage; +t+<?M B
} :q]9F4im
^k;]"NR
privatestaticboolean hasPrePage(int currentPage){ LmePJ
return currentPage == 1 ? false : true; AO$AT_s
} S@FO&o 0
eZLEdTScM
privatestaticboolean hasNextPage(int currentPage, hlaN'j
<C
/.Ak'Vmi
int totalPage){ %, kP_[!>Q
return currentPage == totalPage || totalPage == ^ RA'E@"
rNii,_
0 ? false : true; FM >ae-L-
} [d6!
|)29"_Kk5
jC9us>b
} yZ|"qP1
.h7s.p?
g[3LPKQ
s|]g@czan
DAB9-[y+
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。 [|DKBJ
8AuBs;i
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 ]
3"t]U'f
c+9L6}D
做法如下: 6<._^hyq
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 "6$V1B0KW
MC}t8L=
的信息,和一个结果集List: XH"+oW
java代码: /x6p
a /sj W
`hi=y BO
/*Created on 2005-6-13*/ <+i(CGw
package com.adt.bo; $zMshLT
gBm'9|?
import java.util.List; B7C3r9wj
amu;grH
import org.flyware.util.page.Page; qN)y-N.LI(
~#A}=,4>
/** +jGHR&A t
* @author Joa /SD}`GxH
*/ %9J@##+
publicclass Result { {ALEK
nqcq3o*B
private Page page; W)In.?>]W
Ke\\B o,
private List content; HTJ2D@h
7K1-.uQ
/** mL{P4a 1xf
* The default constructor `Y#At3{
*/ 5Q?Jm~H9
public Result(){ z8Q!~NN-K
super(); *qd:f!Q3
} <'a~ Y3B"o
0
&zp
/** Ts5)r(
* The constructor using fields \G" S7
* M&Ka^h;N
* @param page LVj1NP
* @param content 2$JGhgDI
*/ ;b$P*dSG}
public Result(Page page, List content){ Dqx#i-L23
this.page = page; x sryXex;
this.content = content; Zv u6/#
} Z/#_Swv
w,LtQhQ
/** CLR1CGnn7
* @return Returns the content. O
VV@
*/ m[9.'@ye
publicList getContent(){ :
\+xXb{
return content; >XD?zF)6
} Ott6y
5)k8(kH
/** uN|A}/hr]
* @return Returns the page. `g)}jo`W
*/ Bt+^H6cb
public Page getPage(){ $)i`!7`4=
return page; c/;;zc
} oL<#9)+2*
)ZG;.j
/** 3o<d=@`r
* @param content )dXa:h0RZ
* The content to set. _bFUr
*/ \Pg~j\;F]
public void setContent(List content){ 3nq?Y8yac
this.content = content; +)Z]<O
} fE#(M +(<
')X(P>
/** DXFu9RE\{
* @param page 51#*8u+L
* The page to set. $
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*/ p@m0Oi,=
publicvoid setPage(Page page){ z:Ml;y
this.page = page; bz4Gzp'6k
} Hq3|>OqC2Q
} K$CC ~,D
zC?'Qiuh*
F^i3e31*t
Wv;0PhF
sZ.<:mu[
2. 编写业务逻辑接口,并实现它(UserManager, (m~>W"x/
=
tv70d'
UserManagerImpl) 4"d,=P.{
java代码: 7=G2sOC
S$6|KY u
/x<g$!`X
/*Created on 2005-7-15*/ 2w?q7N%
package com.adt.service; ]-=L7a
|.<_$[v[x
import net.sf.hibernate.HibernateException; p~pD`'%
]g_VPx"
import org.flyware.util.page.Page; mzgt>Qtkz=
P*|N)S)X%
import com.adt.bo.Result; q!Du
J
A~zn;
/** &qv~)ZM$
* @author Joa Y0LZbT3
*/ IkrB}
publicinterface UserManager { Y-VDi.]W
]z'&oz
public Result listUser(Page page)throws =~D? K9o
iSW2I~PD
HibernateException; d
t/AAk6
0YH5B5b
} H;Wrcf2
O[@!1SKT0
xQoZ[
u?osX;'w
L\:|95Yq
java代码: H4$qM_N
'o AmA=
GABZsdFZ!
/*Created on 2005-7-15*/ xL}i9ozZ
package com.adt.service.impl; w^yb`\$
b?H"/Mu.
import java.util.List; |;ztK[(
c4JV~VS+
import net.sf.hibernate.HibernateException; j-<]OOD
j3j?2#vR
import org.flyware.util.page.Page; ]l,BUf-O
import org.flyware.util.page.PageUtil; du65=w4E!
' \JE>#
import com.adt.bo.Result; ]#tB[G
import com.adt.dao.UserDAO; !3Q0Ahf
import com.adt.exception.ObjectNotFoundException; Y.^L^ "%dF
import com.adt.service.UserManager; p|>*M\LE#
+8Xjk\Hi
/** I!x.bp~V!
* @author Joa KX)n+{
*/ 2d)Dhxzxk
publicclass UserManagerImpl implements UserManager { L%'J]HL-
?
SFBUX(p
private UserDAO userDAO; DfXkLOGik
5`;SI36"
/** f|[7LIdh-
* @param userDAO The userDAO to set. 6$u/N gS
*/ wu
<0or2
publicvoid setUserDAO(UserDAO userDAO){ i:lc]B
this.userDAO = userDAO; 0PzSp ]
} qu=~\t1[6
$?= $F
/* (non-Javadoc) ^q7V%{54
* @see com.adt.service.UserManager#listUser p`tz*ewC
%~rEJB@{
(org.flyware.util.page.Page) 3CCs_AO
*/ Llfl I
public Result listUser(Page page)throws \)PB p
v{u3[c
HibernateException, ObjectNotFoundException { Z8v\>@?5R
int totalRecords = userDAO.getUserCount(); L.n@;*
if(totalRecords == 0) ]'.qRTz'\t
throw new ObjectNotFoundException \CB^9-V3
!np_B0`
("userNotExist"); |t,sK aL
page = PageUtil.createPage(page, totalRecords); $BqiC!~
List users = userDAO.getUserByPage(page); (tK_(gO
returnnew Result(page, users); Sd+5Uf`
} qv!(In>u
K#3^GB3P
}
:1'
L+t
/
E`
]U?nYppV
}$ y.qqG
G[64qhTC
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,@*5x'auK
]_KWN$pd
询,接下来编写UserDAO的代码: vYgJu-Sl
3. UserDAO 和 UserDAOImpl: _i=*0Q
java代码: Z{8%Cln
RdCGK?s
aDS:82GMQ
/*Created on 2005-7-15*/ lrrTeE*
package com.adt.dao; *G"hjc$L
X3:1KDVsV
import java.util.List; "~r<ZG
t]xz7VQ
import org.flyware.util.page.Page; &3vm
@
> ,6
import net.sf.hibernate.HibernateException; 1[P}D~ nQ
d59rq<yI
/** K1
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* @author Joa R
iZ)FW
*/ GT6; I7
publicinterface UserDAO extends BaseDAO { j{C~wy!J
>+O0W)g{o
publicList getUserByName(String name)throws '}cSBbl&/n
u`ir(JIj]
HibernateException; $z=a+t *
~d*Q{v~3
publicint getUserCount()throws HibernateException; AD;m[u7
:Drf]D(sMX
publicList getUserByPage(Page page)throws P~7(x7/7~
0\mf1{$"!7
HibernateException; _Sjj|j
vfSPgUB)
} ,='Ihi
z~{08M7
_L,~WYRo
MN: {,#d0
#}Qe{4L
java代码: Dj/Hz\
Df"PNUwA"
w1Bkz\95
/*Created on 2005-7-15*/ rCJ$Pl9R
package com.adt.dao.impl; .ATpwFal
3.movkj
import java.util.List; ]&D dy&V
C eEhe
import org.flyware.util.page.Page; 7mtx^
"P7OD^(x/
import net.sf.hibernate.HibernateException; 9Og
import net.sf.hibernate.Query; :7{GOx
|5>Tf6$(
import com.adt.dao.UserDAO; g?
vz\_
jV%
VN
/** ;CO qu#(
* @author Joa F=\
REq
*/ r1~W(r.x
public class UserDAOImpl extends BaseDAOHibernateImpl `.@udfog^0
&Wy>t8DIK
implements UserDAO { B9(w^l$kZ|
" ILF!z
/* (non-Javadoc) 4 95Y<x}=
* @see com.adt.dao.UserDAO#getUserByName %
jDH{xSMb
>{AE@@PB^
(java.lang.String)
c@A.jc
*/ (-ELxshd
publicList getUserByName(String name)throws RIkIE=+6
'c~SE>
HibernateException { vhMoCLb
String querySentence = "FROM user in class nscnG5'{+
oVK?lQ~y
com.adt.po.User WHERE user.name=:name"; +*OAClt+]
Query query = getSession().createQuery z/#,L!Z3
Le83[E*i
(querySentence); 0 Rb3|te
query.setParameter("name", name); WOPIF~1v
return query.list(); , S^y>
} I(UK9H{0$
Q``1^E'
/* (non-Javadoc) OcB&6!1u
* @see com.adt.dao.UserDAO#getUserCount() ;$tdn?|
*/ @de ZZ
publicint getUserCount()throws HibernateException { pZ Uy (
int count = 0; ts=D
String querySentence = "SELECT count(*) FROM }:?*n:g5
DXJw)%G
w
user in class com.adt.po.User"; y/@Bhzc
Query query = getSession().createQuery &q&z$Gc;m
f (C:J[;Z
(querySentence); @l3&vt2=J
count = ((Integer)query.iterate().next :TVo2Zm[@
,`U>BBBLv
()).intValue();
/$93#$
return count; 7!qeIz
} a<*+rGI
'*[7O2\%/
/* (non-Javadoc) '7' 73
* @see com.adt.dao.UserDAO#getUserByPage Uhu?G0>O
8K^#$,.."
(org.flyware.util.page.Page) xlcCL?qQj
*/ -qpvVLR,
publicList getUserByPage(Page page)throws I!b"Rv=Nf-
ju:}%'
HibernateException {
/1TK+E$
String querySentence = "FROM user in class Dj= {%
M*'8$|Z
com.adt.po.User"; gHgqElr(
Query query = getSession().createQuery C{U*{0}
'`tFZfT
(querySentence); W +Piqf*
query.setFirstResult(page.getBeginIndex()) 6r^ZMW
.setMaxResults(page.getEveryPage()); o>*`wv
return query.list(); #Br`;hL<T
} [cFD\"gJAr
yfwR``F
} wo62R&ac
A99;bf}"
Zk7!CJVM
;=0-B&+v
P:J|![
至此,一个完整的分页程序完成。前台的只需要调用
6x5Q*^w
-7oIphJ=\
userManager.listUser(page)即可得到一个Page对象和结果集对象 Z9H2! Cp
^0"fPG`
的综合体,而传入的参数page对象则可以由前台传入,如果用 GRpwEfG
t<+>E_Xw
webwork,甚至可以直接在配置文件中指定。 bfUKh%!M
j*?E~M.'1K
下面给出一个webwork调用示例: ?gu!P:lZS
java代码: GQ85ykky
)EYs+7/t
"X=^MGV
/*Created on 2005-6-17*/ ZHwl 9n#m
package com.adt.action.user; RK*tZ
1z; !)pG.
import java.util.List; DZ`,QWuA
|+~P; fG
import org.apache.commons.logging.Log; O*2{V]Y
@
import org.apache.commons.logging.LogFactory; +-x+c:
IxA
import org.flyware.util.page.Page; /_JR7BB^X,
I+Y Z+
import com.adt.bo.Result; RYl{89
import com.adt.service.UserService; cEXd#TlY~X
import com.opensymphony.xwork.Action; @Nm{H
n\7>_
/** I(>_as\1
* @author Joa ]c\`EHN
*/ f&F9ImZ
publicclass ListUser implementsAction{ >y}> 5kv
7u1o>a%9
privatestaticfinal Log logger = LogFactory.getLog bTx4}>=5l
A\"4[PXpQ
(ListUser.class); XYV`[,^h&
`&)
private UserService userService; 7lOAu]Zx
Q=<&ew
private Page page; u3cg&lEgT
>7?Lq<H
privateList users; Us6~7L00
*Qngx
/* %YuFw|wO
* (non-Javadoc) 0m4#{^Y
* 1JS5 LS
* @see com.opensymphony.xwork.Action#execute() 6DEH|2
*/ cri-u E?
publicString execute()throwsException{ lBG5~<NT
Result result = userService.listUser(page); ,S}wOjb@
page = result.getPage(); u#ocx[
users = result.getContent(); '*U_!RmQ
return SUCCESS; _0&U'/cs
} #pD=TMefC
uYE"OUNWL
/** QVb{+`.7
* @return Returns the page. BL0xSNE**
*/ kT^`j^Jr
public Page getPage(){ qP/McH?
return page; Kk%
IN9
} Kk \,q?
*EU1`q*
/** mphs^k< Z
* @return Returns the users. (^ J2(
*/ 7*+tG7I @
publicList getUsers(){ JFRbWQ0
return users; U
d+6=Us{
} U,<?]h
q)"yP\
/** M VE:JNm
* @param page #E/|WT
* The page to set. +D h?MQt?
*/ =4/K#cQ
publicvoid setPage(Page page){ Z4k'c+
this.page = page; (>\4%(pnD
} ;M O,HdP;
=EHKu|rX~
/** 4E$6&,\
* @param users ?R@u'4yK
* The users to set. V4*/t#L/
*/ bM,%+9oz;
publicvoid setUsers(List users){ Z%{`j!!p
this.users = users; }o=s"0 a
} 3|Y.+W
;%/}(&E2
/** ;0dl
* @param userService Jk`0yJi$q
* The userService to set. $B )jSxSy
*/ GSGaYq
publicvoid setUserService(UserService userService){ aqP"Y9l
this.userService = userService; s8*Q@0
} aO
*][;0
} 7$kTeKiP
+W|VCz
7MX5hZF"
:<6gP(
_nIt4l7
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, kc[<5^b5
q$B|a5a?
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 pQCW6X
Uot LJa
么只需要: T\TKgO=)
java代码: aslb^
~kZ?e1H
a^)@}4
<?xml version="1.0"?> VpxsgCS
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork c*V/2"
5
Q/l388'
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 0fw>/"v
Zx|VOl,;
1.0.dtd"> E7U.>8C
\2[
<xwork> :W[d&e
Tu=~iQ
<package name="user" extends="webwork- :w9s bW
rW2
interceptors"> E>1%7"
i<
dJ7 !je1N*
<!-- The default interceptor stack name ^Zq3K
LHusy;<E[
--> U1pwk[
<default-interceptor-ref pE]s>Ta
(+9^)No
name="myDefaultWebStack"/> )#Id=c
Uclta
<action name="listUser" KCS},X_
NY%=6><t!
class="com.adt.action.user.ListUser"> u:}yE^8 @
<param
rUBc5@|
(p? B=
name="page.everyPage">10</param> >'{'v[qR[G
<result b59NMGn
4^K<RSYs
name="success">/user/user_list.jsp</result> jY$3
</action> _vOSOnU
a_Z[@W
</package> ~J1UzUxX2
K;~I;G
</xwork> u[LsH
tzG.)Uqs
&BRi& &f
=R||c
}b]z+4Ua(
X8
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 xY`$j'u
'8"$:y
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 \r&9PkHWo
\aGTi
pB
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 fTV3lyk
T@on
ue7
DZU} p
@HP7$U"
$McbVn)~f
我写的一个用于分页的类,用了泛型了,hoho @<=<?T>1
0`kaT
?>
java代码: K7]+. f
*l8:%t\
t|cTl/i
4
package com.intokr.util; u\ }"l2 r
j%Z%_{6Ds*
import java.util.List; S!.H _=z%p
<iznB8@
/** oz?pE[[tm
* 用于分页的类<br> W< :7z
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 4w(#`'I>
* YjwC8#$
* @version 0.01 e'5sT#T9 l
* @author cheng \t%rIr
*/ ~cW,B}
public class Paginator<E> { )\fLS d
privateint count = 0; // 总记录数 P~ODd(
privateint p = 1; // 页编号 ,(Nr_K
privateint num = 20; // 每页的记录数 qBcwM=R3P
privateList<E> results = null; // 结果 0tp3mYd
+jGSD@32>
/** ])$Rw$`w
* 结果总数 %j2ZQ/z
*/ uxD$dd?
publicint getCount(){ .a]9 rQQ&_
return count; L
[=JHW
} I@o42% w2
Eh|v>Yew
publicvoid setCount(int count){ #@K
%Mx
this.count = count; @hj5j;NHK
} 0m&W: c
{K >}eO:K
/** yDe#,|-p
* 本结果所在的页码,从1开始 *BAR`+;U
* NVq3h\[X
* @return Returns the pageNo. %H8s_O
*/ u%I |o s]
publicint getP(){ ynU20g
return p; GilmJ2<
} Kz2s{y~?
s|o+
Im
/** 4~mmP.c
* if(p<=0) p=1 ^Qa!{9o[
* xHi.N*~D
* @param p qfl #ki`,
*/ >m4Q*a4M
publicvoid setP(int p){ zpBkP-%}E
if(p <= 0) 2(K@V6j$M
p = 1; hYEUiQ
this.p = p; .GOF0puiM
} &ub0t9R
@w5x;uB|%G
/** ]U)Yg
* 每页记录数量 [7@9wa1v!
*/ bz\-%$^k
publicint getNum(){ )lDmYt7me
return num; F*j0o
+B5
} Ee 15Y$1
(bo-JOOdY(
/** CKr5L
* if(num<1) num=1 Eu1t*>ZL
*/ <X~P62<
publicvoid setNum(int num){ \O(~:KN
if(num < 1) .<kbYo:MV
num = 1; PQA}_o
this.num = num; _0E KE
} }>< v7
qpXsQim$~
/** R.$1aqA}
* 获得总页数 8(|lP58~
*/ JJVdq-k+`
publicint getPageNum(){ PiZU_~A
return(count - 1) / num + 1; +jN%w{^=
} 5tQZf'pHfd
5><KTya?=
/** l/g6Tv`w
* 获得本页的开始编号,为 (p-1)*num+1 .}ePm(
*/ )H|cri~D
publicint getStart(){ c-q=Ct
return(p - 1) * num + 1; 8D6rShx =
} G"D=ozr
WI}cXXUKm0
/** caXSt2|'
* @return Returns the results. &$8YW]1M
*/ ~zph,bk
publicList<E> getResults(){ o GN*p_g
return results; m*H' Cb
} ?:+sjHzXT
\<0xg[
public void setResults(List<E> results){ c01i!XS
this.results = results; s{dgUX
} K0C3s
x_$`#m{hL5
public String toString(){ Zj5B}[,l\
StringBuilder buff = new StringBuilder G e+T[
ibn(eu<uW
(); M"
R=;n
buff.append("{"); `Tk GI0q
buff.append("count:").append(count); M~,N~ N1
buff.append(",p:").append(p); jU0E=;1
buff.append(",nump:").append(num); Q7 @oAeNd
buff.append(",results:").append fF]w[lLDv
/lDei}
(results); @M&qH[tK-A
buff.append("}"); C q)Cwc[H
return buff.toString(); ckdXla
} y ]D[JX[
U\GuCw
} ,4H/>yPw
H?cJ'Q,5
br%l>Y\"