Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 @v)Z>xv
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 xM jn=\}
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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 Qq,2V
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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 z
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分页支持类: b| L;*<KU
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java代码: J M`w6}
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package com.javaeye.common.util; Df6i*Ko|
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import java.util.List; k|;a"56F
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publicclass PaginationSupport { Vl_6nY;
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publicfinalstaticint PAGESIZE = 30; }1#m+ (;
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privateint pageSize = PAGESIZE; u
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privateList items; F-,gj{s
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privateint totalCount; NW\CEJV
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privateint[] indexes = newint[0]; w'@gzK
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privateint startIndex = 0; Pe%[d[k
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public PaginationSupport(List items, int tT]@yo|?e/
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totalCount){ j<^!"_G]*?
setPageSize(PAGESIZE); u({^8: AYu
setTotalCount(totalCount); .<m]j;|6
setItems(items); Zl>SeTjB-
setStartIndex(0); 2C
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} un "I
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public PaginationSupport(List items, int L.;b(bFe
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totalCount, int startIndex){ iYXD }l;r
setPageSize(PAGESIZE); m212
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setTotalCount(totalCount); SAm%$vz%M
setItems(items); "c%wq0
setStartIndex(startIndex); lNe4e6
} wv\X
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public PaginationSupport(List items, int 4=,J@N-
5IU!BQU
totalCount, int pageSize, int startIndex){ ";/]rwHa)
setPageSize(pageSize); NpVL;6?7T
setTotalCount(totalCount); ZKi&f,:
setItems(items); 'w:ugb9]
setStartIndex(startIndex); lelmX
} T}Tv}~!f
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publicList getItems(){ U%vTmdOY
return items; <'=!f6Wh
} 971=OEyq*
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publicvoid setItems(List items){ kK5&?)3Y:
this.items = items; fN2Sio:
} OX"Na2-el
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publicint getPageSize(){ DAw1S$dM
return pageSize; BK!Yl\I<
} _ZRmD\_t
J^8j|%h%e
publicvoid setPageSize(int pageSize){ #S7oW@
this.pageSize = pageSize; 'aNkU
} Pt"K+]Ym
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publicint getTotalCount(){ J6#h~fp v
return totalCount; 6mcb'hy
} QSaDa@OV
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publicvoid setTotalCount(int totalCount){ gJ l^K
if(totalCount > 0){ 9B~&d(Bm
this.totalCount = totalCount; \S h/<z
int count = totalCount / Tg)F.):
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pageSize; {\>4)TA
if(totalCount % pageSize > 0) KS_+R@3Z
count++; &N.pW=%,N
indexes = newint[count]; a?gF;AYk
for(int i = 0; i < count; i++){ ~gX1n9_n
indexes = pageSize * uyX
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} Ti2cD
}else{ ~W@dF~r
this.totalCount = 0; JE O$v|X
} (aYu[ML
} `n>/MY
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publicint[] getIndexes(){ O/eZ1YAC
return indexes; ~ZafTCa;
} 2P:X_:`~[
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publicvoid setIndexes(int[] indexes){ yu_PZ"l
this.indexes = indexes; \]>821r
} /Am9w$_T[
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publicint getStartIndex(){ %Z6Q/+#fn
return startIndex; bqn(5)% {
} :^(y~q?
45 biy(qa
publicvoid setStartIndex(int startIndex){ X1w11Z7o
if(totalCount <= 0) mc]+j,d
this.startIndex = 0; H:~bWd'iz
elseif(startIndex >= totalCount) 8cO?VH,nk
this.startIndex = indexes |k~AGc
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[indexes.length - 1]; -UEi
elseif(startIndex < 0) _sy{rnaqvb
this.startIndex = 0; C-edQWbcP
else{ co,0@.i
this.startIndex = indexes ];5J
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[startIndex / pageSize]; jNxTy UU
} =*fq5v
} #GGa, @O
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publicint getNextIndex(){ 0=,Nz
int nextIndex = getStartIndex() + ,OlS>>,
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pageSize; ">T\]V$R
if(nextIndex >= totalCount) -+ F,L8
return getStartIndex(); IWYQ67Yj
else k*_Gg
return nextIndex; ]DnAW'm
} O#.YTTj
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publicint getPreviousIndex(){ o;c"-^>
int previousIndex = getStartIndex() - OK4r)
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pageSize; u'? +JUd1
if(previousIndex < 0) E$lbm>jsb$
return0; KS#A*BRQ
else 9{(q[C5m
return previousIndex; }S iR;2W
} 1{/Cr K/o
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} TQb/lY9*
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抽象业务类 l!gX-U%-
java代码: `Fcr`[
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/** 7a>+ma\
* Created on 2005-7-12 2RZa}
*/ wMkHx3XD
package com.javaeye.common.business; Wpf~Ji6||
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import java.io.Serializable; ,|O6<u9
import java.util.List; T}J)n5U}\
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import org.hibernate.Criteria; @V>]95RX
import org.hibernate.HibernateException; |./:A5_h
import org.hibernate.Session; PM!JjMeQh
import org.hibernate.criterion.DetachedCriteria; U
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import org.hibernate.criterion.Projections; OfrzmL<K
import X:t?'41m\
P7>\j*U91{
org.springframework.orm.hibernate3.HibernateCallback; Tf=1p1!3
import
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org.springframework.orm.hibernate3.support.HibernateDaoS *_YH}U
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upport; K!AA4!eUzM
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import com.javaeye.common.util.PaginationSupport; uj)vh
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public abstract class AbstractManager extends u~,hTY(%
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HibernateDaoSupport { G5|nt#>
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privateboolean cacheQueries = false; F,as>X#
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privateString queryCacheRegion; PE;<0Cz\
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publicvoid setCacheQueries(boolean >'#vC]@
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cacheQueries){ N[-$*F,:_
this.cacheQueries = cacheQueries; uo?R;fX26
} HjzAFXRG
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publicvoid setQueryCacheRegion(String k]AL\)
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queryCacheRegion){ {oAD;m`
this.queryCacheRegion = % dtn*NU
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queryCacheRegion; 7[ n
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} g?iZ RM
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publicvoid save(finalObject entity){ ]w,|WZm
getHibernateTemplate().save(entity); 16N|
} 7}NvO"u
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publicvoid persist(finalObject entity){ >mtwXmI
getHibernateTemplate().save(entity); A|PZ<WAY
} N`d%4)|{
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publicvoid update(finalObject entity){ /F^
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getHibernateTemplate().update(entity); n4B
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} ,Y|
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publicvoid delete(finalObject entity){ 1fV)tvU$
getHibernateTemplate().delete(entity); N,8.W"fV
} E|oOd<z
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publicObject load(finalClass entity, 9*~";{O.Oa
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finalSerializable id){ &*8.%qe;
return getHibernateTemplate().load $mf O:%
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(entity, id); H>D?
} n@H;*nI|
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publicObject get(finalClass entity, Wcm'E3c,
}!r
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finalSerializable id){ ~Hd* Xl
return getHibernateTemplate().get g/FT6+&T.
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(entity, id); zRgGSxn
} ZmkH55Cn
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publicList findAll(finalClass entity){ ^Nds@MR{8'
return getHibernateTemplate().find("from cM<08-:v
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" + entity.getName()); oV9{{
} [_ uT+q3
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publicList findByNamedQuery(finalString hAds15 %C
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namedQuery){ x1Z'_Qw
return getHibernateTemplate 7$Wbf4
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().findByNamedQuery(namedQuery); ![4_K':=
} 4\ElMb[]
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publicList findByNamedQuery(finalString query, X>pCkGE
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finalObject parameter){ 'n"we#
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return getHibernateTemplate =j20A6gND
{~#PM>f
().findByNamedQuery(query, parameter); hpbi!g
} 6wbH{}\ll
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publicList findByNamedQuery(finalString query, LOG>x!
8 .K; 2
finalObject[] parameters){ Wwr
return getHibernateTemplate 1fM`n5?"
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().findByNamedQuery(query, parameters); r}(m jC"o
} e%)MIAS0
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publicList find(finalString query){ 1A*
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return getHibernateTemplate().find b5.]}>]t
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(query); |+[Y_j
} Y]`o-dV
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publicList find(finalString query, finalObject Lr
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parameter){ dK8dC1@,X;
return getHibernateTemplate().find iv],:|Mbd
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(query, parameter); /<-=1XJI
} zK_P3rLsS
z TPNQ0=|
public PaginationSupport findPageByCriteria P0sAq7"
@A`j Wao
(final DetachedCriteria detachedCriteria){ " j_cI-@6
return findPageByCriteria 6kAGOjO
@w(|d<5l:L
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 1*6xFn
} 9&6P,ts%Q
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public PaginationSupport findPageByCriteria k=d0%}
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(final DetachedCriteria detachedCriteria, finalint 'mm>E
#_K<-m%9
startIndex){ K3WaBcm
return findPageByCriteria gLFTnMO
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(detachedCriteria, PaginationSupport.PAGESIZE, <R~;|&o,$
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startIndex); paMK]-
} Bva2f:)K|
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public PaginationSupport findPageByCriteria VfDa>zV3
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(final DetachedCriteria detachedCriteria, finalint ;|$o z{Ll
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pageSize, Hr7pcz/#l
finalint startIndex){ mb%U~Na
return(PaginationSupport) i]4n YYS
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getHibernateTemplate().execute(new HibernateCallback(){ ?<\2}1
publicObject doInHibernate Bu?Qyz2O
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(Session session)throws HibernateException { jaavh6h)
Criteria criteria = Br{(sL0e
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detachedCriteria.getExecutableCriteria(session); yOAC<<Tzus
int totalCount = jffNA^e
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((Integer) criteria.setProjection(Projections.rowCount cW"DDm
g
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()).uniqueResult()).intValue(); rce._w }
criteria.setProjection a"t~K
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(null); .!i`YT*jF
List items = wa`c3PQGu
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criteria.setFirstResult(startIndex).setMaxResults o-AF_N
]ZW-`U MO
(pageSize).list(); 7`^Y*:(
PaginationSupport ps = $"MVr5q6
">20`Mj8
new PaginationSupport(items, totalCount, pageSize, 3u+i
6-g>(g
startIndex); ]|=`-)AP3
return ps; /EegP@[
} _Y}cK|3
}, true); 7&%HE\
} ab.B?bx
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public List findAllByCriteria(final fgC@(dvfk
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DetachedCriteria detachedCriteria){ YTTij|(
return(List) getHibernateTemplate G-R83Orl
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().execute(new HibernateCallback(){ JL{fW>5y|
publicObject doInHibernate <r>Sj/w<D
WiQVZ{
(Session session)throws HibernateException { \i}-Y[Dg
Criteria criteria = Aho*E9VW
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detachedCriteria.getExecutableCriteria(session); T/ eX7p1
return criteria.list(); W2zG"Q
} ,`k6@4
}, true); )`ixT)
} C@zG(?X
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public int getCountByCriteria(final :O,r3O6
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DetachedCriteria detachedCriteria){ ue@W@pj
Integer count = (Integer) iWFtb)3B
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getHibernateTemplate().execute(new HibernateCallback(){ `_i|\}tl
publicObject doInHibernate 5ug|crX
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(Session session)throws HibernateException { FUJ<gqL
Criteria criteria = rwio>4=
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detachedCriteria.getExecutableCriteria(session); ZJF+./vN
return mE>{K
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criteria.setProjection(Projections.rowCount euRKYGW
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()).uniqueResult(); W\5 -Yg(@
} mpVD;)?JmM
}, true); FKL@,>!<e
return count.intValue(); wPu.hVz
} v ;Q*0%~
} ;(;~yB|NZ5
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用户在web层构造查询条件detachedCriteria,和可选的 }[drR(]`dO
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 KsK]y,^Z
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PaginationSupport的实例ps。 R#8cOmZ
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ps.getItems()得到已分页好的结果集 .X"&kO>G
ps.getIndexes()得到分页索引的数组 ;*9<lUvu
ps.getTotalCount()得到总结果数 >j$aY
ps.getStartIndex()当前分页索引 i_*.
ps.getNextIndex()下一页索引 ?D_iib7
ps.getPreviousIndex()上一页索引 o:"(\$
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8
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 05\0g9
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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 `
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一下代码重构了。 t%5bDdo
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我把原本我的做法也提供出来供大家讨论吧: OI78wG
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首先,为了实现分页查询,我封装了一个Page类: /FpPf[
java代码: m\/) m]wR
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/*Created on 2005-4-14*/ v.vkQQ0[9
package org.flyware.util.page; 7+@-mJMP$D
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/** L:mE)Xq2
* @author Joa L;L_$hu)
* }R5EuR m\
*/ `d4xX@
publicclass Page { x
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/** imply if the page has previous page */ IR:{ { (
privateboolean hasPrePage; a}|<*!4zUQ
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/** imply if the page has next page */ Mqk|H~l5c
privateboolean hasNextPage; M"{*))O\-c
tq@)J_7|
/** the number of every page */ e Y^zs0
privateint everyPage; -%P}LaC<
h8Oj
E$
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/** the total page number */ >SziRm>Y7
privateint totalPage; 9=/4}!.
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/** the number of current page */ HINk&)FC
privateint currentPage; ]q[(z
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/** the begin index of the records by the current l,(:~KH|
4}cxSl]jf!
query */ k\*?<g
privateint beginIndex; n5BD0q
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/** The default constructor */ +/kOUz/]
public Page(){ B B'qbX3xK
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} K"5q387!
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/** construct the page by everyPage YRf$?xa
* @param everyPage +oO7UWs>6
* */ $]}K ;
public Page(int everyPage){ PO0Od z
this.everyPage = everyPage; m$(OQ,E
} @2d9
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/** The whole constructor */ ?[>Y@we
public Page(boolean hasPrePage, boolean hasNextPage, -'d`(G"
+%KkzdS'
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int everyPage, int totalPage, omy3<6
int currentPage, int beginIndex){ iyr8*L\
this.hasPrePage = hasPrePage; 99By.+~pX
this.hasNextPage = hasNextPage; O0`ofFN
this.everyPage = everyPage; AFvv+
ss
this.totalPage = totalPage; 77aUuP7Iw
this.currentPage = currentPage; n_LK8
this.beginIndex = beginIndex; TvT>UBqj=
} 3B,dL|q(@J
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/** ,3MHZPJ?k]
* @return 6@FhDj2X
* Returns the beginIndex. 0Bkz)4R
*/ Cc`-34/%
publicint getBeginIndex(){ Oj_F1.
r
return beginIndex; aUc#,t;Qd
} cq
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AGS(ud{
/** B1E:P`t
* @param beginIndex ; !t?*
* The beginIndex to set. ^J^FGo|M
*/ QkD]9#Id&
publicvoid setBeginIndex(int beginIndex){ yI07E "9
this.beginIndex = beginIndex; Fn4yx~0
} O:T
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/** |]?W`KN0
* @return 8f)pf$v`
* Returns the currentPage. fi ~@J`
*/ )t7MD(
publicint getCurrentPage(){ GVn'p
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return currentPage; 7
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} n6Uf>5
<
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/** wmXI8'~F&
* @param currentPage
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* The currentPage to set. ;1nXJ{jKw
*/ Y9vi&G?Jl
publicvoid setCurrentPage(int currentPage){ iCh8e>+
this.currentPage = currentPage; rLmc(-q
} S*J\YcqSC
S>*i\OnI'
/** o]qwN:8^
* @return ~dLbhjden
* Returns the everyPage. '|5o(6u'
*/ y x#ub-A8
publicint getEveryPage(){ ev+H{5W8
return everyPage; h?B1Emlq
} l. l)w
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/** _!Tjb^
* @param everyPage <Uf`'X\e6
* The everyPage to set. Cd]A1<6s
*/ a&)!zhVP
publicvoid setEveryPage(int everyPage){ gE=9K @
this.everyPage = everyPage; wS&D-!8v
} KECW~e`
di9OQ*6a7
/** ^u"WWLZ
* @return 0nB[Udk?
* Returns the hasNextPage. FyPG5-
*/ qIQ
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publicboolean getHasNextPage(){ VQG$$McJ
return hasNextPage; @H+L1H%9n
} 9(z) ^G
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/** e00}YWf%
* @param hasNextPage hDZyFRg
* The hasNextPage to set. em )%U
*/ )flm3G2u
publicvoid setHasNextPage(boolean hasNextPage){ \awkt!Wa
this.hasNextPage = hasNextPage; -Q?c'e
} 0a<h,s0"2
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/** /7p(%vr
* @return r#&JfAo
* Returns the hasPrePage. &V+KM"Ow
*/ X%(NI(+x,
publicboolean getHasPrePage(){ Ej6ho 0_
return hasPrePage; 3k(tv U+eC
} ?K2}<H-
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/** >b5 ;I1o=y
* @param hasPrePage %N(>B_t\
* The hasPrePage to set. #9.%>1{6Y
*/ HJym|G>%?
publicvoid setHasPrePage(boolean hasPrePage){ BtKor6ba
this.hasPrePage = hasPrePage; Hy,""Py
} _FcTY5."S
UHU ,zgM
/** aot2F60J,
* @return Returns the totalPage. xaoR\H
* (&r`
l&0
*/ [UC_
publicint getTotalPage(){ Iu`S0#+
return totalPage; En\q. 3
5
} ^q&|7Ou-
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/** P?n4B \!
* @param totalPage ^EkxZ4*g
* The totalPage to set. 5jwv! L<n
*/ bqA`oRb\
publicvoid setTotalPage(int totalPage){ VmQ'
this.totalPage = totalPage; mEi(DW)(
} 6vps`k$,~
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} +,$pcf<[V
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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 Qo^(r$BD
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个PageUtil,负责对Page对象进行构造: mD&I6F[s
java代码: %eIaH!x:
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/*Created on 2005-4-14*/ 3"v>y]$U
package org.flyware.util.page; ']I!1>v$[
o~\.jQQxa
import org.apache.commons.logging.Log; _-543B}
import org.apache.commons.logging.LogFactory; p[].4_B;
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/** &IzNoB
* @author Joa w3sU& |N
* aBG^Xhx
*/ *x]*%
publicclass PageUtil { ~x<?Pj
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privatestaticfinal Log logger = LogFactory.getLog n=F
r v*"Z
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(PageUtil.class); Xy!NBh7I
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/** ~I;x_0iY4
* Use the origin page to create a new page -Q
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* @param page v7KBYN
* @param totalRecords {7]maOg>7J
* @return pmWy:0 R
*/ /J/V1dC}]D
publicstatic Page createPage(Page page, int ]d7A|)q
8Yf*vp>T/x
totalRecords){ (s&]V49
return createPage(page.getEveryPage(), OPj NmdeS
DmPsE6G}
page.getCurrentPage(), totalRecords); pOn &D
} hxM{}}.E
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/** %,HUn`
* the basic page utils not including exception j3`YaWw
hi/d%lNZ
handler MMpId
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* @param everyPage '7oCWHq[
* @param currentPage ITqAy1m@C
* @param totalRecords 6_u!{
* @return page 7qUg~GJX
*/ 39
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publicstatic Page createPage(int everyPage, int U!uJ )mm
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currentPage, int totalRecords){ n^l*oEl
everyPage = getEveryPage(everyPage); 6m(? (6+;K
currentPage = getCurrentPage(currentPage); jIrfJ*z
int beginIndex = getBeginIndex(everyPage, ob2_=hQnC
6D2ot&5WW
currentPage); TlkhI
int totalPage = getTotalPage(everyPage, kp<Au)u
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totalRecords); 0#8, (6
boolean hasNextPage = hasNextPage(currentPage, ;]m;p,$
32SkxcfrCK
totalPage); )AR-b8..o
boolean hasPrePage = hasPrePage(currentPage); ^gp]tAf
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returnnew Page(hasPrePage, hasNextPage, {6RA~
everyPage, totalPage, _a& Z$2O
currentPage, Z8Y&#cB
9{j`eAUZl
beginIndex); lZ[J1:%
} |? fAe{*
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privatestaticint getEveryPage(int everyPage){ N'&>bO?@`
return everyPage == 0 ? 10 : everyPage; ^9 LoxU-
} oA~0"}eS
AA=rjB9
privatestaticint getCurrentPage(int currentPage){ 4[]*=
return currentPage == 0 ? 1 : currentPage; glU9A39qx?
} ^AJ
2Y_}v
V?"U)Y@Y
privatestaticint getBeginIndex(int everyPage, int f"*4R
kG
=P9rOK=
currentPage){ k\T]*A
return(currentPage - 1) * everyPage; U>.5vK.+
} >]gB@tn[
LiQH!yHW
privatestaticint getTotalPage(int everyPage, int LA59O@r
cl]W]^q-Cx
totalRecords){ Te?PYV-
int totalPage = 0; &-Wt!X 3
5EI"5&`*
if(totalRecords % everyPage == 0) id :
^|
totalPage = totalRecords / everyPage; 4~$U#$u_
else ~J+
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totalPage = totalRecords / everyPage + 1 ; e],(d7 Jo
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return totalPage; t g-(e=S4P
} DBcR1c&<H
vf<Dqy <M.
privatestaticboolean hasPrePage(int currentPage){ rKslgZhQ
return currentPage == 1 ? false : true; @jMo/kO/A
} -X7x~x-
uaKbqX
privatestaticboolean hasNextPage(int currentPage, V(0Y
`RE>gX
int totalPage){ G9QvIXRi
return currentPage == totalPage || totalPage == H*3u]Ebh
Q#ksf
h!D
0 ? false : true; DA>nYj-s
} piIz ff
>d]-X]
-#/DK
} a`^$xOK,
n[K%Xs)
Q{uO/6
-]u>kjiIT
is^R8a
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。 K3tW Y
4-
Oe@w$?
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 PX&}g-M9
1(# H%
做法如下: ,Fkq/h
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 #`%S[)RT
A=|a!N/
的信息,和一个结果集List: P(8
u L|^
java代码: |P|2E~[r
&Fuk+Cu{
Zj ` ;IYFG
/*Created on 2005-6-13*/
fB]2"(
package com.adt.bo; OiZ-y7;k^
'@#(jY0_
import java.util.List; ~-lUS0duh
)c9Xp:
import org.flyware.util.page.Page; uBg#zx
"oZ_1qi<
/** k$J!,!q
* @author Joa Nr,I`x\N
*/ GtIAsC03
publicclass Result { )y:))\>
RN@)nc_
private Page page; bZfq?
4,X CbcC
private List content; G^SJhdO(Q
>rP[Xox'
/** iS.gN&\z^
* The default constructor =+DhLH}8
*/ P2s\f;Dwr
public Result(){ mA,{E-T
super(); f8r7SFwUv
} +/mCYI
#sjGju"#_
/** $kmY[FWu?
* The constructor using fields 4o@:+T:1
* 811QpYA
* @param page 1?8M31
* @param content T9r6,yY
*/ \?8q&o1=]
public Result(Page page, List content){ &;JeLL1J
this.page = page; 8
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this.content = content; 3jJV5J'"
} k6z]"[yu
L5KcI
/** AFYdBK]
* @return Returns the content. ]S9Z5l0
*/
:-hVbS0I
publicList getContent(){ S-Vxlku]
return content; =c&.I}^1L
} FdEUZ[IT`{
%Q]thv:
/** ,g"JgX
* @return Returns the page. 2dJE`XL
*/ Rx&.,gzj[
public Page getPage(){ LXrk5>9
return page; HP<a'| r
} KXcRm)
152s<lu1Z
/** c`lL&*]
* @param content I|;zGmg#k
* The content to set. !a!4^zqp
*/ IFa~`Gf [
public void setContent(List content){ +tg${3ti_
this.content = content; Rd]<591
} 'T7 3V
^4\0,>
/**
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* @param page Z:x`][vg
* The page to set. mC0Dj O
*/ toOdL0hCe
publicvoid setPage(Page page){ w&VDe(:~
this.page = page; SXJjagAoML
} 8+Gwv
SDU
} 9}fez)m:g0
-*J!Ws(9
1Id"|/b%$
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H%Lln#
2. 编写业务逻辑接口,并实现它(UserManager,
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UserManagerImpl) 2 1+[9
java代码: @g" vuaG}
2!b##`UjA7
`Nz`5}8.?
/*Created on 2005-7-15*/ .XkVdaX
package com.adt.service; `P:[.hRu
H<?s[MH[
import net.sf.hibernate.HibernateException; -2 8bJ,
"d}ey=$h4
import org.flyware.util.page.Page; fuF{8-ua
(#z6w#CU(
import com.adt.bo.Result; ^7;s4q
yO7#n0q
/** :c8d([)$
* @author Joa n)35-?R/M
*/ 'W("s
publicinterface UserManager { %yl17:h#
A
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public Result listUser(Page page)throws a <F2]H=J
0B}2~}#
HibernateException; j}(m$j'
6'<[QoW];
} G!%8DX5
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88?O4)c
&rX#A@=
C[#C/@
java代码: [9MbNJt 8~
3Z#WAhfS:
?*7Mn`
/*Created on 2005-7-15*/ -g|ji.
package com.adt.service.impl; @^ m0>H
fd>&RbUp
import java.util.List; DrxQ(yo}
yg~@}_C2_
import net.sf.hibernate.HibernateException; n;>=QG
-v
*8)va
import org.flyware.util.page.Page; $P%cdJ T0
import org.flyware.util.page.PageUtil; ~$"2,&
P4/~_$e
import com.adt.bo.Result; L*vKIP<EMM
import com.adt.dao.UserDAO; gA@Zx%0j
import com.adt.exception.ObjectNotFoundException; ]T2Nr[vu
import com.adt.service.UserManager; E7aG&K
n"Bc2}{
/** :rjfAe=s
* @author Joa %&V%=-O_7
*/ S)4p'cUwq
publicclass UserManagerImpl implements UserManager { HTvUt*U1
_)~VKA]""
private UserDAO userDAO; n}(A4^=4KQ
K1]3zLnS
/** *-Vr=e<8
* @param userDAO The userDAO to set. *0Fz." v
*/ y%kZ##
publicvoid setUserDAO(UserDAO userDAO){ lNWP9?X
this.userDAO = userDAO; Vi}E9I4
} 4fjwC,,
X:g#&e_
/* (non-Javadoc) 'V&Uh]>
* @see com.adt.service.UserManager#listUser x',6VTz^
r`h".=oD
(org.flyware.util.page.Page) ~<s^HP2U{
*/ S'hUh'PZ
public Result listUser(Page page)throws ~{vB2
kY{$[+-jR
HibernateException, ObjectNotFoundException { LNHi}P~
int totalRecords = userDAO.getUserCount(); { w sT
if(totalRecords == 0) v'S5F@ln
throw new ObjectNotFoundException ]6A wd A
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("userNotExist"); 9
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page = PageUtil.createPage(page, totalRecords); ZrZDyXL
List users = userDAO.getUserByPage(page); K4YD}[
returnnew Result(page, users); v_WQ<G?
} U/|JAg#
D>HbJCG4^
} $&KkZ
*)6\V}`
;^E_BJm
pIYXYQ=Z
s;*
UP
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 -V[x
q
VfP\)Rl
询,接下来编写UserDAO的代码: mw;4/
/R
3. UserDAO 和 UserDAOImpl: 0(:SEiz6s
java代码: FOMJRq
[ ;sTl~gC
BOq9\g`5s
/*Created on 2005-7-15*/ IAq
o(Qm
package com.adt.dao; Y#~A":A
a'dlAda
import java.util.List; %d(= >
8"ZS|^#
import org.flyware.util.page.Page; .5}Gt>4XM
z0SF2L H
import net.sf.hibernate.HibernateException; .Y^cs+-o
c:>&YGmhu
/** V %D1Q}X
* @author Joa nb<o o:^
*/ jC{KI!kPt
publicinterface UserDAO extends BaseDAO { K5BL4N
#d-zH:uq
publicList getUserByName(String name)throws &vn2u bauS
+`g&hO\W
HibernateException; TB+k[UxB
k,k>w#&
publicint getUserCount()throws HibernateException; G
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6pbCQ
q
publicList getUserByPage(Page page)throws ,u PcQ
72yJv=G
HibernateException; QHf&Z*Xtl
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} `&