Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 S*3$1BTl
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 aG@GJ@w
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 ^H<VH
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 436SIh
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分页支持类: {EU]\Mp0j
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java代码: /dX,]OFm
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package com.javaeye.common.util; 7#*O|t/'
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import java.util.List; &|zV Wl
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publicclass PaginationSupport { a,M/i&.e`
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publicfinalstaticint PAGESIZE = 30; o1]1I9
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privateint pageSize = PAGESIZE; ?PB}2*R
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privateList items; F
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privateint totalCount; ^'sOWIzeiY
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privateint[] indexes = newint[0]; 'xM\txZ;
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privateint startIndex = 0; 8Waic&lX~
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public PaginationSupport(List items, int 6XVJ/qZ
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totalCount){ 2b#>~
setPageSize(PAGESIZE); ?* dfIc
setTotalCount(totalCount); ooYs0/,{
setItems(items); zfml^N
setStartIndex(0); gp{P _
} Qcs0w(
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public PaginationSupport(List items, int VN@ZYSs
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totalCount, int startIndex){ mP)im]H
setPageSize(PAGESIZE); P(zquKm
setTotalCount(totalCount); B"RZpx
setItems(items); iF+50d
setStartIndex(startIndex); 90$`AMR
} 9>5]y}.{
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public PaginationSupport(List items, int 'BEM:1)
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totalCount, int pageSize, int startIndex){ UFa 00t^5
setPageSize(pageSize); !P _'n
setTotalCount(totalCount); <{1 3Nd'o
setItems(items); n] n3/wpO
setStartIndex(startIndex); Yg`z4U'6~
} `&/ zOMp
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publicList getItems(){ LGVGr
return items; Tj=g[)+K
} GwlAEh P
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publicvoid setItems(List items){ K~z9b4a>
this.items = items; *icxK
} ';x5 $5k'
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publicint getPageSize(){ MXpj_+@
return pageSize; m=IA/HOR^
} \RTX fe-`
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publicvoid setPageSize(int pageSize){ a,p7l$kK
this.pageSize = pageSize; !1?Nc}T0Q&
} *
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publicint getTotalCount(){ K fNR)
return totalCount; s^AZ)k~J(
} 3sGe#s%
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publicvoid setTotalCount(int totalCount){ ~7=w,+
if(totalCount > 0){ DcLx[C
this.totalCount = totalCount; C[(Exe
int count = totalCount / `L}Irt}
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pageSize; P!2[#TL0
if(totalCount % pageSize > 0) T k>N4yq
count++; $yg}HS7HC
indexes = newint[count]; !7[Rhk7bW
for(int i = 0; i < count; i++){ ldm=uW
indexes = pageSize * l.i&.;f
!.k
i; y3C$%yv0
} .:s**UiDR
}else{ X*C4NF0
this.totalCount = 0; F%QVn.
} uBC*7Mkm
} %S4pkFR
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publicint[] getIndexes(){ |"a%S,I'
return indexes; o%tvwv
} <El6?ml@
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publicvoid setIndexes(int[] indexes){ TXQY&7
this.indexes = indexes; Kth^WHL
} 47XQZ-}4
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publicint getStartIndex(){ QFf lx
return startIndex; dPRGL
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} 21U,!
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publicvoid setStartIndex(int startIndex){ F/w!4,'<?5
if(totalCount <= 0) .Su9fjy%
this.startIndex = 0; GP/3r[MH
elseif(startIndex >= totalCount) 7nHlDPps)
this.startIndex = indexes "V cG3.
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[indexes.length - 1]; /z+}xRS
elseif(startIndex < 0) t=ry\h{Pc
this.startIndex = 0; < F Cr
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else{ O<h`[1eUjS
this.startIndex = indexes X/nb7_M
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[startIndex / pageSize]; x3my8'h@
} KdOy3O_5N
} q-}J0vu\K
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publicint getNextIndex(){ ,*V{gpC7
int nextIndex = getStartIndex() + !g~xn2m$R
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pageSize; >c7fg^@
if(nextIndex >= totalCount) CtA0W\9w5a
return getStartIndex(); 3u8H F-
else &`63"^y
return nextIndex; {E`f(9r:
} (byFr9z
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publicint getPreviousIndex(){ G?d28p',.
int previousIndex = getStartIndex() - Y0U<l1(|
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pageSize; h^bbU.
if(previousIndex < 0) Ydu=Jg5u7
return0; Qp${/
else J%_
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return previousIndex; 'on, YEp
} 6?ylSQ]1
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} d7tH~9GX8
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抽象业务类 qGgT<Rd~1
java代码: / '}O-h
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/** %Ow,.+m
* Created on 2005-7-12 6P!M+PO
*/ mg*[,_3q33
package com.javaeye.common.business; Vo"\nj
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import java.io.Serializable; Ssr
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import java.util.List; 6546"sU
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import org.hibernate.Criteria;
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import org.hibernate.HibernateException; ?
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import org.hibernate.Session; %Sfew/"R0
import org.hibernate.criterion.DetachedCriteria; -mG3#88*
import org.hibernate.criterion.Projections; <D
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import rRL:]%POT
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org.springframework.orm.hibernate3.HibernateCallback; i}+K;,Da:8
import h{kAsd8 G
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org.springframework.orm.hibernate3.support.HibernateDaoS k|nv[xY0
c ++tk4
upport; do%6P^qA
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import com.javaeye.common.util.PaginationSupport; RpR;1ktF>
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public abstract class AbstractManager extends ED @9,W0
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HibernateDaoSupport { z6b!,lp
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privateboolean cacheQueries = false; U*=ebZno
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privateString queryCacheRegion; J(VJMS;_
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publicvoid setCacheQueries(boolean a}+|2k_
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cacheQueries){ =zt@*o{F
this.cacheQueries = cacheQueries; )avli@W-3j
} InMF$pw
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publicvoid setQueryCacheRegion(String X4lz?Y:*
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queryCacheRegion){ kA{[k
this.queryCacheRegion = $+)SW{7
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queryCacheRegion; gEMxK2MNXj
} u)MdFz
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publicvoid save(finalObject entity){ -S
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getHibernateTemplate().save(entity); P|_>M SO1'
} !&Vp5]c
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publicvoid persist(finalObject entity){ lh&Q{t(+8
getHibernateTemplate().save(entity); J"L+`i
} e-ILUzT
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publicvoid update(finalObject entity){ r'uD|T H
getHibernateTemplate().update(entity); ^i2W=A'P
} tpO%)*
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publicvoid delete(finalObject entity){ %%}U
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getHibernateTemplate().delete(entity); lO9ML-8C1
} 5\V>Sj(
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publicObject load(finalClass entity, Tf)qd\
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finalSerializable id){ "m.j cKt
return getHibernateTemplate().load iVLfAN @
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(entity, id); &p%0cjg"Q
} yf*^Y74
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publicObject get(finalClass entity, +Fp8cT=1
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finalSerializable id){ D.9qxM"Z>
return getHibernateTemplate().get R$IxR=hMx
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(entity, id); 9}p?h1NrY
} 4!64S5(7t
) gbns'Z<
publicList findAll(finalClass entity){ A}v!vVg
return getHibernateTemplate().find("from )-%3;e<w
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" + entity.getName()); (pN:ET B
} DJvmwFx
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publicList findByNamedQuery(finalString D^8]+2r
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namedQuery){ `>-fU<Q1
return getHibernateTemplate ce@1#}*
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().findByNamedQuery(namedQuery); >zFk}/
} GdHFgxI
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publicList findByNamedQuery(finalString query, ^S:S[0\,
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finalObject parameter){ ix2V?\
return getHibernateTemplate `Y>'*4a\
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().findByNamedQuery(query, parameter); vqO d`_)
} DSjEoWj
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publicList findByNamedQuery(finalString query, fUj[E0yOF
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finalObject[] parameters){ n-zAkKM
return getHibernateTemplate T% 74JRQ
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().findByNamedQuery(query, parameters); O(x1Ja,&
} ;Z^\$v9?
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publicList find(finalString query){ )E9[=4+*C$
return getHibernateTemplate().find UMtnb:ek
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(query); m31l[e
} kNq>{dNRx
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publicList find(finalString query, finalObject b9nTg
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parameter){ [g)HoR=&
return getHibernateTemplate().find y7pwYRY
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(query, parameter); ]R%[cr
} XhEZTg;
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public PaginationSupport findPageByCriteria 6z`l}<q
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(final DetachedCriteria detachedCriteria){ \f~m6j$D_
return findPageByCriteria 3dO~Na`S
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); dfy]w4ETB
} &/dYJv$[9
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public PaginationSupport findPageByCriteria m\zCHX#n
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(final DetachedCriteria detachedCriteria, finalint N+lhztYQ?
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startIndex){ gq%U5J"x;J
return findPageByCriteria ?D>%+rK8c
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(detachedCriteria, PaginationSupport.PAGESIZE, >EE}P|=-
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startIndex); p1F{ v^
} z)%Ke~)<\@
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public PaginationSupport findPageByCriteria ]{Y7mpdB
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(final DetachedCriteria detachedCriteria, finalint ~8JOPzK
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pageSize, "L4ZE4|)
finalint startIndex){ %CoO-1@C
return(PaginationSupport) uNKf!\Y
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getHibernateTemplate().execute(new HibernateCallback(){ u@]rR&h`
publicObject doInHibernate _tlr8vL
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(Session session)throws HibernateException { `d c&B
Criteria criteria = /,d]`N!
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detachedCriteria.getExecutableCriteria(session); ?,}:)oA_
int totalCount = inHlL
- +<ai
((Integer) criteria.setProjection(Projections.rowCount h\T}$jgfWm
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()).uniqueResult()).intValue(); !w1acmo<_
criteria.setProjection >//yvkZ9,
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(null); u+lNcyp"MW
List items = /np05XhEa
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criteria.setFirstResult(startIndex).setMaxResults vRkVPkZ6|
V~#8lu7;
(pageSize).list(); y$Fk0s*>
PaginationSupport ps = ]qb>O:T
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new PaginationSupport(items, totalCount, pageSize, !L[$t~z
8B?*?,n5
startIndex); B#]:1:Qn
return ps; we0haK
} ke<l@wO
}, true); y_``-F&Z
} RH9P$;.7
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public List findAllByCriteria(final g& ou[_A
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DetachedCriteria detachedCriteria){ rF$S
return(List) getHibernateTemplate qWU59:d^{
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().execute(new HibernateCallback(){ lT?Vt`==~M
publicObject doInHibernate XE'3p6
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(Session session)throws HibernateException { 3qQ}U}-; |
Criteria criteria = _RNP_$a
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detachedCriteria.getExecutableCriteria(session); <S^Hy&MD>
return criteria.list(); ux8K$$$
} '/s/o]'sUd
}, true); }0Q
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} L)i6UAo
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public int getCountByCriteria(final }S"qU]>8a
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DetachedCriteria detachedCriteria){ .unlr_eA
Integer count = (Integer) O]XgA0]
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getHibernateTemplate().execute(new HibernateCallback(){ ^V~^[Yp
publicObject doInHibernate R5i xG9
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(Session session)throws HibernateException { 9ec>#Vxx
Criteria criteria = z57q|
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detachedCriteria.getExecutableCriteria(session); ]k$:sX
return qgs:9V
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criteria.setProjection(Projections.rowCount EK Ac>g
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()).uniqueResult(); '=H3Y_{oO
} 8%`h:fE
}, true); %J+ w9Z
return count.intValue(); F0wW3+G
} -k
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} "yK)9F[9Mo
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用户在web层构造查询条件detachedCriteria,和可选的 IrIW>r} -
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 V`0Y
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PaginationSupport的实例ps。 hh$i1n
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ps.getItems()得到已分页好的结果集 24po}nrO
ps.getIndexes()得到分页索引的数组 sDvy(5
ps.getTotalCount()得到总结果数 cJ>^@pd{
ps.getStartIndex()当前分页索引 sC ?e%B
ps.getNextIndex()下一页索引 r3Kx
ps.getPreviousIndex()上一页索引 /g1;`F(MS/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 [U$`nnp
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 e
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一下代码重构了。 ~iIFe+6
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我把原本我的做法也提供出来供大家讨论吧: ZftucD|ZY/
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首先,为了实现分页查询,我封装了一个Page类: Sq5}v]k@&
java代码: 29W`L2L
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/*Created on 2005-4-14*/ MM~4D
package org.flyware.util.page; a~k*Gd(
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/** {M23a
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* @author Joa 'N&s$XB,
* :4>LtfA
*/ @sRb1+nn
publicclass Page { ?i\$U'2*z3
}5d|y*
/** imply if the page has previous page */ "/x/]Qx2
privateboolean hasPrePage; Of
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/** imply if the page has next page */ m[w~h\FS
privateboolean hasNextPage; 9S?b &]
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/** the number of every page */ q#0yu"<
privateint everyPage; pW&8 =Ew
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/** the total page number */ C?rb}(m
privateint totalPage; ']sIU;h3
ZV!*ZpTe~
/** the number of current page */ 9x14I2
privateint currentPage; #b1/2=PA
ai)?RF
/** the begin index of the records by the current lC^?Jk[N
`J}FSUn\
query */ `
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privateint beginIndex; d 8z9_C-
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/** The default constructor */ WWA!_
public Page(){ )IuwI #pm
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} 3UcOpq2i\
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/** construct the page by everyPage YY$O"!."
* @param everyPage hw&~OJeo
* */ yiczRex%rq
public Page(int everyPage){ Zk #C!]=
this.everyPage = everyPage; }
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} af/;D r@
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/** The whole constructor */ !_:|mu'
public Page(boolean hasPrePage, boolean hasNextPage, +s5Yg,4*
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int everyPage, int totalPage, peU1
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int currentPage, int beginIndex){ l 4cTN
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this.hasPrePage = hasPrePage; ={nuz-3
this.hasNextPage = hasNextPage; -:V2Dsr6;
this.everyPage = everyPage; f q*V76F
this.totalPage = totalPage; 68!=`49r>
this.currentPage = currentPage; Z15b'^)?9
this.beginIndex = beginIndex; &&n-$WEl
} M5B?`mTl
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/** N4,!b_1
* @return WtbOm
* Returns the beginIndex. YifTC-Q;
*/ 1<f,>BQ+
publicint getBeginIndex(){ ^^( 4xHN
return beginIndex; oSoU9_W
} /7b$C]@k
3q1u9`4;
/** V7>{,
* @param beginIndex (a8oI)~
* The beginIndex to set. YwF\
*/ {qBbzBG
publicvoid setBeginIndex(int beginIndex){
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this.beginIndex = beginIndex; wEIAU
} 7A>glZ/x
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/** o
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* @return $@L}/MO
* Returns the currentPage. YRP$tz+
_
*/ N:rnH:g+:
publicint getCurrentPage(){ 12yX`9h>
return currentPage; 2aGK}sS6
} u}KEH@yv
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/** 2<+9lk
* @param currentPage 2a:JtJLl
* The currentPage to set. CFx$r_!~
*/ :WdiH)Zv
publicvoid setCurrentPage(int currentPage){ W_G'wU3R
this.currentPage = currentPage; lmr:PX
} ESv&x6H
wz5*?[4
/** 0t}&32lL&
* @return 8Vqh1<
* Returns the everyPage. KfLp cV
*/ WUqfY?5
publicint getEveryPage(){ J9/}ZD^
return everyPage; u:&Lf
} G |vG5$Nf
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/** . vQCX1V(
* @param everyPage j*N:Kdzvl
* The everyPage to set. cXvq=Rb
*/ $v+t~b
publicvoid setEveryPage(int everyPage){ 9!oNyqQ
this.everyPage = everyPage; qQUCK
} 38eeRo
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/** [0mg\n?
* @return Mi_/
^
* Returns the hasNextPage. V$fvf#T
*/
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publicboolean getHasNextPage(){ Sj<WiQ%<
return hasNextPage; gEU|Bx/!=
} sYb( g'W*'
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/** (lVHKg&U[
* @param hasNextPage m339Y2%=
* The hasNextPage to set. -V)DKf"f
*/ -:o4|&g<*
publicvoid setHasNextPage(boolean hasNextPage){ P ||:?3IH
this.hasNextPage = hasNextPage; K PSHBv-#
} ];1Mg
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/** |\MgE.N
* @return mdTCe
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* Returns the hasPrePage. vMV}M%~
*/ 2bk~6Osp
publicboolean getHasPrePage(){ pT` oC&
return hasPrePage; O
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} UMbM3m=\
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/** v5;V$EGD&
* @param hasPrePage f?A1=lm~
* The hasPrePage to set. na1*^S`[
*/ I
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publicvoid setHasPrePage(boolean hasPrePage){ ?
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this.hasPrePage = hasPrePage; <wZ2S3RNA
} N3J;_=<4
|B;tv#mKD
/** Ma,2_oq+
* @return Returns the totalPage. ]V K%6PQ0
* .`3O4]N[
*/ ==\Qj{
7`
publicint getTotalPage(){ e$3{URg
return totalPage; yy%'9E ldc
} C.[abpc
@Js^=G2
/** af<R.
* @param totalPage 2\p8U#""
* The totalPage to set. lU[" ZFP
*/ O+^l>+ZGj?
publicvoid setTotalPage(int totalPage){ Gd8FXk,.!
this.totalPage = totalPage; \' gb{JO
} "NgfdLz
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} j%m9y_rg}
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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 fvDt_g9 oI
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个PageUtil,负责对Page对象进行构造: ~<?+(V^D
java代码: ,33[/j
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/*Created on 2005-4-14*/ /uM;g9 m
package org.flyware.util.page; '*~_!lE5
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import org.apache.commons.logging.Log; 5mxYzu;#]
import org.apache.commons.logging.LogFactory; u._B7R&>
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/** ,u1Yn}
* @author Joa W/3,vf1
* Nj<}t/e
*/ +M"Fv9
publicclass PageUtil { 2+7rLf`l
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privatestaticfinal Log logger = LogFactory.getLog N<|_tC+ct
GEdWpYKS-`
(PageUtil.class); \CP)$0j-&o
ok"v`76~f5
/** [zO:[i 7
* Use the origin page to create a new page 9Q<8DMX^
* @param page WPmH4L>T
* @param totalRecords K\7\
* @return [<+A?M=
*/ 5v f?E"\r
publicstatic Page createPage(Page page, int Vy:I[@6@+
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totalRecords){ l$PSID
return createPage(page.getEveryPage(), 3
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(}W+W\.
page.getCurrentPage(), totalRecords); =z5'A|Wa=,
} b1(7<o
3 %ppvvQ
/** F3XB};
* the basic page utils not including exception LyaFWx
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handler 4$);x/
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* @param everyPage 7hs1S|
* @param currentPage J|9kWjOf+i
* @param totalRecords Uq:WW1=kh
* @return page G% |$3
*/ O T*C7=
publicstatic Page createPage(int everyPage, int q`HuVilNH
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currentPage, int totalRecords){ Aj854 L(!
everyPage = getEveryPage(everyPage); JumZ>\'p(
currentPage = getCurrentPage(currentPage); tai=2,'
int beginIndex = getBeginIndex(everyPage, TN xl?5:
;"}yVV/4
currentPage); /k$h2,O"*
int totalPage = getTotalPage(everyPage, M.|cl#
,f4VV\
totalRecords); Q]9+-p(=
boolean hasNextPage = hasNextPage(currentPage, U7)#9qS4
gn2*'_V~3
totalPage); ,N[N;Uoj
boolean hasPrePage = hasPrePage(currentPage); otA59 ;Z
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returnnew Page(hasPrePage, hasNextPage, }e7os0;s
everyPage, totalPage, o$*aAgS+
currentPage, gx-ib/_f1
,g.*Mx`-
beginIndex); 'pCZx9*c
} k$u\\`i]oC
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privatestaticint getEveryPage(int everyPage){ {XHAQ9'
return everyPage == 0 ? 10 : everyPage;
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} V`/E$a1&
UlG8c~p
privatestaticint getCurrentPage(int currentPage){ C 2f=9n/
return currentPage == 0 ? 1 : currentPage; qO;.{f
} aC\O'KcH
y /$Q5P+o
privatestaticint getBeginIndex(int everyPage, int f<14-R=
g*]hmkYe9
currentPage){ {|KFgQ'\
return(currentPage - 1) * everyPage; V`c"q.8
} -8HK_eQn
Dl
a }-A:
privatestaticint getTotalPage(int everyPage, int #\|Ac*>
N~""Lc&
totalRecords){ p?uk|C2
int totalPage = 0; BBV"nm_(/
Ic 5TtN~/>
if(totalRecords % everyPage == 0) !2.(iuE
totalPage = totalRecords / everyPage; \kDQ[4mGq
else N\,[(LbA&
totalPage = totalRecords / everyPage + 1 ; P3Wnso
PykVXZ7j;
return totalPage; ;6 ?a8t@
} 50s1o{xwc
o1kTB&E4B
privatestaticboolean hasPrePage(int currentPage){ IhIz 7.|
return currentPage == 1 ? false : true; %DK0s(*w0
} zBQV2.@
wMW."gM|
privatestaticboolean hasNextPage(int currentPage, RP@U0o
PBeBI:
int totalPage){ \;!}z3W w
return currentPage == totalPage || totalPage == 2)~`.CD?L
i;flK*HOZ9
0 ? false : true; j8cIpbp8x
} WE{fu{x
w#XD4kwQG
R]h3a:ic
} `rLcJcW
ag_*Z\
uPT2ga ]
URd0|?t9^L
@A5'vf|2;.
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。 %,1xOl4l
U<YcUmX
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 9{GEq@`7
rAn:hR{
做法如下: Vk tc
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 )+ V)]dS@%
o=nF .y
的信息,和一个结果集List: qj7}]T_
java代码: W? F Q
x5(6U>-Y
Y&XO:jB
/*Created on 2005-6-13*/ 0h=}BCb+i
package com.adt.bo; WYUel4Z
t] CA!i`
import java.util.List; [HEljEv
/E39Z*
import org.flyware.util.page.Page; y}F;~H~P
th1;Ym+Ze
/** ;!+-fn4C
* @author Joa %lnVzGP
*/ lR>p
publicclass Result { EKD?j
Ob&m&2s,
private Page page; DFXHD,o
ELN1F0TneH
private List content; )n&6= Li
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/** g5C$#<28
* The default constructor 5|jsv)M+
*/ -U{CWn3G
public Result(){ =h@t#-Z"
super(); }`$s"Iv@
} _f1;Hhoa
'5m4kDs
/** FNw0x6,~R
* The constructor using fields dC<2%y
* #z1/VZ
* @param page 5SMV3~*P
* @param content YNB7`:
*/ j "s7P%
public Result(Page page, List content){ j8G$ , ~v
this.page = page; l$&dTI<#
this.content = content; Y3\EX
} s&4&\Aq}x#
#`ZBA>FLaQ
/** 7 w<e^H?
* @return Returns the content. i5,yrPF
*/ HU/2P` DGP
publicList getContent(){ '~9w<dSB!r
return content; q@^^jlHP
} !,^y!+,Qy
x*sDp3f[*
/** <N:)Xf9`
* @return Returns the page. S,s#D9NU
*/ uznYLS
public Page getPage(){ 8B(=Y;w
return page; ?Dl; DE1
} 1u8hnG
+MqJJuWB
/** Hz"FGwd
* @param content 'T|EwrS j
* The content to set. !Ln 'Mi_B
*/ hD[r6c
public void setContent(List content){ AHo }K\O?r
this.content = content; M>Q3;s
} vGnFX0?h
9X&=?+f
/** kWacc&*|
* @param page s f.z(o
* The page to set. )$GCur~
*/ e"%uOuIYX
publicvoid setPage(Page page){ oj[~H}>
this.page = page; ckb(+*+l
} &ty-aB=F
} &Hyy .a
qj/Zk[
WH"'Ju5}
{<$tEj:
FUXJy{n6"2
2. 编写业务逻辑接口,并实现它(UserManager, 01&@8z'E
2acTw#
UserManagerImpl) ${rWDZ0Z
java代码: k 1a?yH)=
Ai"MJ6)
qW4DW4
/*Created on 2005-7-15*/ +\*b?x
package com.adt.service; :7i x`C2
Eg&:yF}?(
import net.sf.hibernate.HibernateException; Uq @].3nf
*kpP)\P
import org.flyware.util.page.Page; @u`W(Ow
OFBEJacy
import com.adt.bo.Result; }.pqV
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PhPe7^
/** cs7^#/3<
* @author Joa 2$MoKOx8$
*/ bIlNA )g
publicinterface UserManager { &uF~t
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public Result listUser(Page page)throws 5
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0y t36Du
HibernateException; omGzyuPF
Qv`: E
} P*B@it
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c|(J%@B)
Caz5q|Oo
java代码: d#XgO5eyO
<.Pt%Kg^BS
$P#x>#+[A
/*Created on 2005-7-15*/ IN@o9pUjV
package com.adt.service.impl; h-|IZ}F7
v%c/eAF
import java.util.List; 7M
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mR Vh
zRd.!Rv
import net.sf.hibernate.HibernateException; R?;mu^B
"G~!J\
import org.flyware.util.page.Page; pKpB
import org.flyware.util.page.PageUtil; "O-X*>?f
EADN
import com.adt.bo.Result; #t;]s<
import com.adt.dao.UserDAO; xMNQT.A
import com.adt.exception.ObjectNotFoundException; O9zMD8
import com.adt.service.UserManager; Dn@ZS _f
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-
/** =+UtAf<n
* @author Joa `"}).{N]C
*/ uY(8KW
publicclass UserManagerImpl implements UserManager { @87Y/_l
W!R0:-
private UserDAO userDAO; :<bhQY
|O6/p7+.
/** M)!"R [V
* @param userDAO The userDAO to set. $./aKJ1B
*/ 9r+'DX?>
publicvoid setUserDAO(UserDAO userDAO){ Ww60-d}}Q
this.userDAO = userDAO; (sQXfeMz
} DQ3L=
PVH Or^
/* (non-Javadoc) ^"p. 3Hy
* @see com.adt.service.UserManager#listUser VBix8|
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(org.flyware.util.page.Page) ]Ml
*/ NA/`LaJ
public Result listUser(Page page)throws ^"D^D`$@
{Q37a=;,
HibernateException, ObjectNotFoundException { NN2mOJ:-
int totalRecords = userDAO.getUserCount(); W6}>iB
if(totalRecords == 0) UimofFmI%
throw new ObjectNotFoundException j'U1lEZm2
{J
izCUo_'
("userNotExist"); 3N-pND0>p
page = PageUtil.createPage(page, totalRecords); $[Z~BfSQ
List users = userDAO.getUserByPage(page); 2"?D aX
returnnew Result(page, users); SepwMB4@
} d{Jk:@.1
Ex
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} "^6Fh"]
jd-ccnR l
o+}k$i!6
I/O/*^T
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 yc~<h/}#
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询,接下来编写UserDAO的代码: O^=+"O]
3. UserDAO 和 UserDAOImpl: x 55W"q7
java代码: ?RS:I%bL
te2vv]W1
Kcp YHWCa.
/*Created on 2005-7-15*/ \u{4=-C.
package com.adt.dao; u>.a; BO
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import java.util.List; #"KC29!Yj
!hZ:
\&V
import org.flyware.util.page.Page; \Z3K ~
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kVB
import net.sf.hibernate.HibernateException; eK
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-$o0P'Vx
/** 7`;f<QNo
* @author Joa iLZY6?_^
*/ Q17dcgd
publicinterface UserDAO extends BaseDAO { |@'O3KA
/P@%{y
publicList getUserByName(String name)throws cZ?$_;=
3k9n*jY0
HibernateException; L55UeP\
rkR5>S( 2M
publicint getUserCount()throws HibernateException; 3~tu\TH6d
qjhV/fsfb
publicList getUserByPage(Page page)throws F/BR#J1
{CI4AT!?W
HibernateException; $'3xl2T
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} "}qs+
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ltgtD k
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$ch`.$wx
java代码: hI!BX};+}
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+)<PK(
.>F4s_6l
/*Created on 2005-7-15*/ \ m~?yq8H
package com.adt.dao.impl; Zf@B<
m
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import java.util.List; 3._
ep
$\h-F8|JMX
import org.flyware.util.page.Page; ap}p?r
nS%jnp#
import net.sf.hibernate.HibernateException; 2L 1,;
import net.sf.hibernate.Query; c#}K,joeU
Q l)hIf$Oo
import com.adt.dao.UserDAO; i m;6$3
!Yb !Au[
/** 8i`>],,ch
* @author Joa ( ~5M{Xh
*/ r)'vn[A
public class UserDAOImpl extends BaseDAOHibernateImpl |}
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implements UserDAO { `9K5 ;]
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/* (non-Javadoc) ":Tm6Nj
* @see com.adt.dao.UserDAO#getUserByName Yw3'9m^
(8h4\utA
(java.lang.String) c]ARgrH-
*/ F=e9o*z
publicList getUserByName(String name)throws 1]2]l*&3
_=s9o/Cn]
HibernateException { -Y/i
h(I^
String querySentence = "FROM user in class O+=%Mz(l
4kM/`g6?,q
com.adt.po.User WHERE user.name=:name"; {s0%XG1$
Query query = getSession().createQuery Y\-xX:n.\
UrvUt$WO
(querySentence); dz9U.:C
query.setParameter("name", name); Z{0BH{23
return query.list(); f+ceL'fr
} 8-nf4=ll
~%/Rc`
/* (non-Javadoc) zg<-%r'$
* @see com.adt.dao.UserDAO#getUserCount() .
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*/ B]"`}jn
publicint getUserCount()throws HibernateException { ^_bG{du
int count = 0; `sCaGCp
String querySentence = "SELECT count(*) FROM ,-y9P
)FQ"l{P
user in class com.adt.po.User"; LOx+?4|y
Query query = getSession().createQuery _K~h?
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lWId
0eNS
(querySentence); eA4:]A"
count = ((Integer)query.iterate().next +Ua|0>?
F$?Ab\#B
()).intValue(); ;yt6Yp.6e
return count; w'H'o!*/
} l:V
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F(HfXY3
/* (non-Javadoc) >s{I@#9
* @see com.adt.dao.UserDAO#getUserByPage D9oNYF-V
tbRW6
(org.flyware.util.page.Page) V|MGG
*/ ={:a
N)
publicList getUserByPage(Page page)throws .Ix3wR9
X=$Jp.
HibernateException { _AX9Mu]
String querySentence = "FROM user in class 'V:Q :
/88s~=
com.adt.po.User"; %PYl
Query query = getSession().createQuery crM5&L9zF
@N>7+
4
(querySentence); yV{B,T`W
query.setFirstResult(page.getBeginIndex()) PdcIHN
.setMaxResults(page.getEveryPage()); A#"Wk]jX
return query.list(); &$~fz":1!
} C 5.3[
lhN@,q
} V*4Z.3/E5
3^o(\=-JX
k6Kc{kY
fc9;ZX7
Ap
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至此,一个完整的分页程序完成。前台的只需要调用 R{#< NE
l$;"yVdks
userManager.listUser(page)即可得到一个Page对象和结果集对象 9* )&hhBs,
dEoIVy _9R
的综合体,而传入的参数page对象则可以由前台传入,如果用 c|Ivet>3
nj[TTndJt
webwork,甚至可以直接在配置文件中指定。 `>:5[Y
;}46Uc#WS
下面给出一个webwork调用示例: +94)BxrY
java代码: &bsq;)wzs
+lym8n~-O
+vh|m5"7I7
/*Created on 2005-6-17*/ NfgXOLthM
package com.adt.action.user; Hy.u6Jt*/
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import java.util.List; (0$~T}lH
Bs~~C8+
import org.apache.commons.logging.Log; n1f8jS+'}
import org.apache.commons.logging.LogFactory; ]" 'yf;g
import org.flyware.util.page.Page; @Po5AK3cy
iE~!?N|a3
import com.adt.bo.Result; g&Vhu8kNIA
import com.adt.service.UserService; }Ce9R2
import com.opensymphony.xwork.Action; 7OV^>"S
YJJ1N/Z1
/** AjVC{\Ik
* @author Joa m!V,W*RNr
*/ k"N>pjgd$
publicclass ListUser implementsAction{ %~LY'cfPse
zKQ<Zr
privatestaticfinal Log logger = LogFactory.getLog HGQ</5Z
sfM"!{7
(ListUser.class); FZe/3sY
=z.j{%
private UserService userService; G]K1X"W?
#I/P9)4
private Page page; Qa{5]+E
VdHT3r
privateList users; iGW|j>N
U%q)T61
/* KYFKH+d>m
* (non-Javadoc) V"/.An|
* xVx s~p1
* @see com.opensymphony.xwork.Action#execute() -c`xeuzK'
*/ w 3t,S3!
publicString execute()throwsException{ mrTf["K
Result result = userService.listUser(page); Ni_H1G
page = result.getPage(); @ st>#]i4
users = result.getContent(); [?]N
GTr#
return SUCCESS; 7H7
Xbi@
} 6$`< Y?
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/** iM]O
* @return Returns the page. Y 6a`{'
*/ F&Md+2
public Page getPage(){ xIM,0xM2
return page; EmNVQ1w
} )&c2+Y@
c2E /-n4K@
/** *6s_7{;
* @return Returns the users. V+gZjuN$
*/ [OC(~b
publicList getUsers(){ f1'ByV'2
return users; uyj!$}4
} '@n"'vks(\
/`PYk]mJh
/** {wSi?;[Gq
* @param page 7e<=(\(yl
* The page to set. *p{p.%Qs:
*/ i$Y#7^l%k
publicvoid setPage(Page page){ V.~kG ,Ht
this.page = page; /J`}o}
} mv9D{_,pD
-)A:@+GF
/** t^#1=nK
* @param users f|> rp[Gk
* The users to set. YU,zQ V'
*/ {j wv+6]U
publicvoid setUsers(List users){ </I%VHP,[f
this.users = users; > X~\(|EM
} uLdHE5vr
5wK==hZ
/** vl (``5{
* @param userService 1g;2e##)
* The userService to set. Kw fd
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*/ <J8c dB!e
publicvoid setUserService(UserService userService){ ?eJ' $
this.userService = userService; *bK=<{d1P
} S>lP?2J
} z~H1f$}
d?oXz| ;H(
X9*n[ev
5gz ^3R|`f
Q& [!+s:2J
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, >N^<Q4%2
cW3'057
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 wSR|uh
49FP&NgK
么只需要: XDK Me}
java代码: _`2%)#^o
'(K4@[3t
dsIbr"m
<?xml version="1.0"?> eF3NyL(A
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ?V`-z#y7
3W'fEh5
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;MfqI/B{
|$
PA
1.0.dtd"> < F5VJ
_a&gbSQv
<xwork> &v:zS$m>
!
fk W;|
<package name="user" extends="webwork- <Sot{_"li
)CXlPbhY?
interceptors"> =eA|gt
yzEyOz@Q
<!-- The default interceptor stack name UP#@gxF
*zRig|k !H
--> BB}WfA
<default-interceptor-ref nOC\ =<Nsg
a" s2N%{
name="myDefaultWebStack"/> 091m$~r*
O72g'qFPE
<action name="listUser" +v/y{8Fu
DN^+"_:TB
class="com.adt.action.user.ListUser"> qkfof{z
<param smCACQ$(
gj;gl
="3
name="page.everyPage">10</param> #19O5
<result #X]*kxQ<
xxGm T.&
name="success">/user/user_list.jsp</result> .XgY&5Qk
</action> ^E%R5JN
-#%M,Qb
</package> z,;XWv?
33%hZ`/>
</xwork> I=DVMG|
zd$'8/Cq
Q`i@['?p
+.djC3^:
@+;.W>^h
h.-L_!1B7
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 %lbvK^
/
0$!.
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 jJ"(O-<)D
`U0XvWPr[
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 h]@'M1D%
xkf2;
W.
d',4)
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T Tbe{nb
我写的一个用于分页的类,用了泛型了,hoho ~xzr8 P
5[2kk5,
java代码: *~U*:>hS
y ;mk]
5[g&0
package com.intokr.util; \<I&utn
:V$\y up
import java.util.List; GX23c
i
i^WY/ OhL
/** 'xd8rN%T
* 用于分页的类<br> Xcfd]29
* 可以用于传递查询的结果也可以用于传送查询的参数<br> v$\<L|
* &y0Gdzf