Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 bVLBqa=
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 h^QLvOuR
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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
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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 FIMM\W
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。 -!@]z2uU
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分页支持类: 0P_=Oy"l-
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java代码: NL^;C3u
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package com.javaeye.common.util; V; pRw`
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import java.util.List; X%C`('"R
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publicclass PaginationSupport { CMhl* dH
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publicfinalstaticint PAGESIZE = 30; $?Km3N\?v
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privateint pageSize = PAGESIZE; ltWEA
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privateList items; t.rlC5
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privateint totalCount; =I.uf
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privateint[] indexes = newint[0]; &0*7]Wo*
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privateint startIndex = 0; m~I@q
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public PaginationSupport(List items, int /wi*OZ7R
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totalCount){ &gLXS1O
setPageSize(PAGESIZE); 9kzJ5}
setTotalCount(totalCount); V3S"LJ
setItems(items); *Uw" `l
setStartIndex(0); gB<1;_KW
} m2a[E0
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public PaginationSupport(List items, int %!\iII
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totalCount, int startIndex){ :
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setPageSize(PAGESIZE); sC'PtFK8z
setTotalCount(totalCount); rff_=(?i
setItems(items); :Z[|B(U
setStartIndex(startIndex); h
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} Gh5 3Pne
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public PaginationSupport(List items, int *b4W+E
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totalCount, int pageSize, int startIndex){ ,. HS )<B
setPageSize(pageSize); |jI|},I
setTotalCount(totalCount); gJH^f3
setItems(items); 79z/(T+
setStartIndex(startIndex); t`-
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} }~v&
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publicList getItems(){ rDWwu'
return items; /EW=OZ/
} Wh)>E!~9
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publicvoid setItems(List items){ v t_lM
this.items = items; {,=U]^A
} 2Rqpok4
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publicint getPageSize(){ yJ:rry
return pageSize; F Jp<J
} 7 \AoMk}
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publicvoid setPageSize(int pageSize){ yRivf.wH
this.pageSize = pageSize; j;<s!A#
} ]pWn%aGv*Y
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publicint getTotalCount(){ d"=)=hm!
return totalCount; )GfL?'Z
} 2U`!0~pod
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publicvoid setTotalCount(int totalCount){ F]L96&
if(totalCount > 0){ ?BX}0RWMh7
this.totalCount = totalCount; m f\tMik<
int count = totalCount / ~#dfZa&
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pageSize; ?X+PNw|pf
if(totalCount % pageSize > 0) C1uV7t*\
count++; zWrynJ}s
indexes = newint[count]; L0R$T=~%)
for(int i = 0; i < count; i++){ %KPQ|^WE
indexes = pageSize * X"V)oC
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} C{G;G@/7
}else{ Byh!Snoe
this.totalCount = 0; OWp`Wat
} E&ReQgBft
} -nZDFC8y$
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publicint[] getIndexes(){ eF(oHn,
return indexes; uvRX{q4
} Eb8~i_B-
1 XpqnyL&
publicvoid setIndexes(int[] indexes){ ~Zw37C9J
this.indexes = indexes; !iL6 /
} y[/:?O}g4
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publicint getStartIndex(){ h%5keiA
return startIndex; h^YUu`P
} yJ>Bc
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publicvoid setStartIndex(int startIndex){ v=daafO
if(totalCount <= 0) Z6nQW53-
this.startIndex = 0; FP")$
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elseif(startIndex >= totalCount) Q?bC'147O
this.startIndex = indexes hG}gKs
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[indexes.length - 1]; y,6KU$G
elseif(startIndex < 0) >x]ir
this.startIndex = 0; 8yybZ@
else{ \' &,9lP
this.startIndex = indexes RJ-J/NhWyI
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[startIndex / pageSize]; `*xSn+wL`_
} <Wd_m?z
} &{bNa:@
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publicint getNextIndex(){ +fHqGZ]
int nextIndex = getStartIndex() + 4YXp,U
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pageSize; 8g?2( MT;
if(nextIndex >= totalCount) Y}h&dAr
return getStartIndex(); 39x
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else %6x3G
return nextIndex; Knp}88DR^j
} ~ymSsoD^
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publicint getPreviousIndex(){ 55Xfu/hQ
int previousIndex = getStartIndex() - <.ZD.u
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pageSize; 2gW+&5;4
if(previousIndex < 0) mj ,Oy
return0; bV:MOj^
else (e32oP"
return previousIndex; ^[EXTBk@:
} u}7r\MnwK,
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} miV 8jaV
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抽象业务类 &-KQ
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java代码: {~V_6wY g
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/** GXR7Ug}k
* Created on 2005-7-12 \,G19o}`Es
*/ '<h@h*R
package com.javaeye.common.business; 7'7o^>
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import java.io.Serializable; ,]4.|A_[Rq
import java.util.List; U\q?tvn'J
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import org.hibernate.Criteria; D7C%Y^K]>E
import org.hibernate.HibernateException; MNX-D0`g
import org.hibernate.Session; E6xWo)`%5s
import org.hibernate.criterion.DetachedCriteria; hOe$h,E']
import org.hibernate.criterion.Projections; q X]ej2
import 9$^v*!<z\
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org.springframework.orm.hibernate3.HibernateCallback; +}C M2>M
import G 'CYvV
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org.springframework.orm.hibernate3.support.HibernateDaoS zU#
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upport; Ifj%" RI
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import com.javaeye.common.util.PaginationSupport; u2 U4MV1C
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public abstract class AbstractManager extends ;{rl
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HibernateDaoSupport { =@k3*#\
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privateboolean cacheQueries = false; _LLE~nUK"/
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privateString queryCacheRegion; |bmc6G[
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publicvoid setCacheQueries(boolean }J:WbIr0!
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cacheQueries){ 8;P_KRaE
this.cacheQueries = cacheQueries; _1?Fyu&<5
} nHB`<B
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publicvoid setQueryCacheRegion(String Xqas[:)7+
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queryCacheRegion){ (ZEDDV2
this.queryCacheRegion = D"n
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queryCacheRegion; )h(yh50
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} g$S<_$Iey
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publicvoid save(finalObject entity){ Xu\2 2/Co
getHibernateTemplate().save(entity); LWP&Si*j
} q8vRUlf
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publicvoid persist(finalObject entity){ <*&2b
getHibernateTemplate().save(entity); cWL7gv\|
} {%z}CTf#
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publicvoid update(finalObject entity){ +yu^Z*_
getHibernateTemplate().update(entity); |y7#D9m
} _Y,d|!B#L
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publicvoid delete(finalObject entity){ wB W]w
getHibernateTemplate().delete(entity); PRF^<%mkI
} (`Q_^Bfyl
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publicObject load(finalClass entity, zgHF-KEV
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finalSerializable id){ ;hp?wb
return getHibernateTemplate().load ppM^&6x^
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(entity, id); \)T4NN
} &:*|K xX
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publicObject get(finalClass entity, }[I|oV5*+&
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finalSerializable id){ eEkbD"Q
return getHibernateTemplate().get RJZ4fl
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(entity, id); D*#r
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} '5"`H>[
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publicList findAll(finalClass entity){ a=3{UEi'o
return getHibernateTemplate().find("from T Jp0^&Q
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" + entity.getName()); (s.S
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} ur2`.dY>3"
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publicList findByNamedQuery(finalString &za~=+
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namedQuery){ tmI2BBv
return getHibernateTemplate s"\o6r
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().findByNamedQuery(namedQuery); o\YF_235
} nANoy6z:
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publicList findByNamedQuery(finalString query, 5zH?1Z~*
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finalObject parameter){ hkL[hD
return getHibernateTemplate 8TnByKZz
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().findByNamedQuery(query, parameter); y(RK|r
} 0Ie9T1D=
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publicList findByNamedQuery(finalString query, =j1rw
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finalObject[] parameters){ ul$YV9[\
return getHibernateTemplate 5:H9B
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().findByNamedQuery(query, parameters); GlVD!0
} -*EK-j
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publicList find(finalString query){ KD7RI3'?
return getHibernateTemplate().find cTeEND)
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(query); O2Mo ~}
} bu#}`/\_
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publicList find(finalString query, finalObject ]l'W=_XDg
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parameter){ J$?*qZ(oO
return getHibernateTemplate().find 8vcV-+x
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(query, parameter); ivbuS-f=r
} Whq@>pX8
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public PaginationSupport findPageByCriteria 0VB~4NNR
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(final DetachedCriteria detachedCriteria){ Osdw\NNH~M
return findPageByCriteria ?b~V uo
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Xo*=iD$Jys
} 1v4(
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public PaginationSupport findPageByCriteria h+x"?^
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(final DetachedCriteria detachedCriteria, finalint 5"5D(
( {H5k''
startIndex){ Rt<8&.m4
return findPageByCriteria t "J"G@1)
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(detachedCriteria, PaginationSupport.PAGESIZE, 1;[\xqJ
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startIndex); q@p-)+D;
} !\H!9FR
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public PaginationSupport findPageByCriteria tw]RH(g+#
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, 78\:{i->ta
finalint startIndex){ (@dh"=Lt\
return(PaginationSupport) Qc z7IA
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getHibernateTemplate().execute(new HibernateCallback(){ _gB`;zo
publicObject doInHibernate lu(<(t,Lbs
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(Session session)throws HibernateException { 92GO.xAD?
Criteria criteria = ho_;;y
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detachedCriteria.getExecutableCriteria(session); /GNRu
int totalCount = $LZf&q:\]*
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((Integer) criteria.setProjection(Projections.rowCount pAYH"Q6~)I
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()).uniqueResult()).intValue(); oQ 5g0(J~
criteria.setProjection iZQwo3"8r
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(null); Z
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List items = l,*v/95h
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criteria.setFirstResult(startIndex).setMaxResults \CL |=8[2
cX@~Hk4=\
(pageSize).list(); o*\kg+8
PaginationSupport ps = T"'"T]^
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new PaginationSupport(items, totalCount, pageSize, UcDJ%vI
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startIndex); _`L,}=um'
return ps; ?^us(o7-
} bv>;%TF
}, true); Ix%h/=I
} LKG],1n-
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public List findAllByCriteria(final ~!'%m(g
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DetachedCriteria detachedCriteria){ -@G|i$!
return(List) getHibernateTemplate ]6</{b
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().execute(new HibernateCallback(){ BUv;BzyV
publicObject doInHibernate ~-Rr[O=E
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(Session session)throws HibernateException { R)t"`'6|
Criteria criteria = MwL'
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detachedCriteria.getExecutableCriteria(session); d5]9FIj
return criteria.list(); Y*O7lZuF%
} S)z
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}, true); BN@*CG
} dh%C@n:B
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public int getCountByCriteria(final R5G~A{w0
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DetachedCriteria detachedCriteria){ #;a
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Integer count = (Integer) UKQ,]VC
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getHibernateTemplate().execute(new HibernateCallback(){ 5SK{^hw
publicObject doInHibernate ?};}#%971
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(Session session)throws HibernateException { /]T#@>('
Criteria criteria = Xcicqywe?
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detachedCriteria.getExecutableCriteria(session); P@p(Y2&~g
return FgNO# %
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criteria.setProjection(Projections.rowCount 8^$}!9B~JZ
];^A8?
()).uniqueResult(); RM-|?%
} NyJU?^f&v
}, true); Q}W6?XDu
return count.intValue(); 09 eS&J<R
} lKI1bs]i
} 6CLrP}
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用户在web层构造查询条件detachedCriteria,和可选的 $B*E k>EK
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 "}Ch2K
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PaginationSupport的实例ps。 >z
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ps.getItems()得到已分页好的结果集 ;)5d
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ps.getIndexes()得到分页索引的数组 hv}rA,Yd
ps.getTotalCount()得到总结果数 Yp./3b VO
ps.getStartIndex()当前分页索引 n%3rv?m7
ps.getNextIndex()下一页索引 q+3Z3v
ps.getPreviousIndex()上一页索引 ,!|/|4vh
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 d%81}4f:
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 A0cC)bd&
bAeC=?U
一下代码重构了。 @ _U]U
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我把原本我的做法也提供出来供大家讨论吧: iRS )Z)
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首先,为了实现分页查询,我封装了一个Page类: x<"1T
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java代码: KFdV_e5lU
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/*Created on 2005-4-14*/ dfiA- h
package org.flyware.util.page; &kHp}\
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/** hewX)
* @author Joa x
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* tjBs>w
*/ rC14X} X6
publicclass Page { \$/)o1SG
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<
/** imply if the page has previous page */ d `>M-:dF
privateboolean hasPrePage; UQaLhKv:
~urIA/
/** imply if the page has next page */ 8t!(!<iF0
privateboolean hasNextPage; #gMMhB=
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/** the number of every page */ %UI.E=`n
privateint everyPage; (#BkL:dg
e Pq(:ih
/** the total page number */ a57Y9.H`o
privateint totalPage; Mhm3u
}\:3}'S.$
/** the number of current page */ 8E&}+DR?
privateint currentPage; |o6
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/** the begin index of the records by the current ?FVX &{{V
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query */ @vss:'l
privateint beginIndex; #M$[C d
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/** The default constructor */ &8_]omuNV
public Page(){ R5g-b2Lm
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} h8Q+fHDYv
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/** construct the page by everyPage 9 JBPE
* @param everyPage .9
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* */ C<?}?hhb
public Page(int everyPage){ WW{5[;LYiB
this.everyPage = everyPage; +(x^5~QX
} O%H_._#N`
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/** The whole constructor */ mM!'~{r[-
public Page(boolean hasPrePage, boolean hasNextPage, jGl8y!aM
)XmV3.rI
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int everyPage, int totalPage, "X T7;!
int currentPage, int beginIndex){ ]|it&4l
this.hasPrePage = hasPrePage; :'91qA%Wr
this.hasNextPage = hasNextPage; =@AWw:!:,
this.everyPage = everyPage; V&;1n
this.totalPage = totalPage; J 05@SG':
this.currentPage = currentPage; U&yXs'3a&
this.beginIndex = beginIndex; .+MJ' bW
} 1uZ[Ewl]
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/** "~(qp_AI
* @return z8_m<uewz
* Returns the beginIndex. ns[v.YDL
*/ B8UtD
publicint getBeginIndex(){ veAg?N<c
p
return beginIndex; RbzSQr>a\
} /:3:Ky3
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/** /x,gdZPX
* @param beginIndex e:fp8 k<
* The beginIndex to set. cjAKc|N J
*/ <`k\kZM
publicvoid setBeginIndex(int beginIndex){ ."&,_F
this.beginIndex = beginIndex; id<i|
} |t+M/C0y/
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/** .<`i!Ls
* @return ZQXv-"
* Returns the currentPage. I_6NY,dF
*/ ,yus44w[
publicint getCurrentPage(){ 1rKKp h
return currentPage; l9KLP
} s:3 altv
#"-?+F=rk
/** 5Ds/^fA
* @param currentPage I=o[\?u*_
* The currentPage to set. to,DN2rN
*/ x|U~?
publicvoid setCurrentPage(int currentPage){ F-[zuYGp
this.currentPage = currentPage; PtCO';9[
} NAjY,)>'K
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/** 1^XuH('
* @return 'N^\9X0
* Returns the everyPage. d0Xb?-
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*/ Z:DEET!c'k
publicint getEveryPage(){ RO[Ko-m|/N
return everyPage; ^]l^q'?>:
} PPk\W7G
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/** :f%FM&b
* @param everyPage DX GClH
* The everyPage to set. CF"$&+ s9
*/ rCfr&>nn
publicvoid setEveryPage(int everyPage){ 7K.&zn
this.everyPage = everyPage; J!5BH2bg
} Z?X0:WK
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/** _J(n~"eR
* @return xxkUu6x#
* Returns the hasNextPage. /WlK*8C
*/ @Gp=9\L
publicboolean getHasNextPage(){ ?PVJeFH
return hasNextPage; !$Aijd s5
} ]T|9>o!
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/** [p[nK=&r
* @param hasNextPage F}3<q
* The hasNextPage to set. !`=ms1%U
*/ ]@X5'r"
publicvoid setHasNextPage(boolean hasNextPage){ z@;]Hy
this.hasNextPage = hasNextPage; W%LTcm
} 3D_Ky Z~M+
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/** [M>Md-pj
* @return :*bv(~FW
* Returns the hasPrePage. %x@
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*/ Ww5c9orXn
publicboolean getHasPrePage(){ 6BM[RL?T
return hasPrePage; \{r-e
} Ft%HWGE
vzV,}
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/** vvA=:J4/i)
* @param hasPrePage h 'VN& T,
* The hasPrePage to set. ?_mcg8A@@*
*/ (ii6w d<*
publicvoid setHasPrePage(boolean hasPrePage){ 0\v98g<[+
this.hasPrePage = hasPrePage; )006\W|t9
}
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/** }L
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* @return Returns the totalPage. r=GF*i[3
* q/y4HT,x
*/ MuNM)pyxp
publicint getTotalPage(){ r@C2zF7
return totalPage; P^m+SAAB
} z'@j9vT
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/** Y[%1?CREP
* @param totalPage RC7|@a
* The totalPage to set. *Q2;bmIc
*/ C!Cg.^;
publicvoid setTotalPage(int totalPage){ VBc[(8o
this.totalPage = totalPage; eduaG,+k7p
} \#4??@+Xf
|GuIp8~
} V3;4,^=6Dd
s( @w1tS.
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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 D|8vS8p
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个PageUtil,负责对Page对象进行构造: u@|izRk
java代码: aE}1~`
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/*Created on 2005-4-14*/ _;mN1Te
package org.flyware.util.page; DLMG<4Cd~
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import org.apache.commons.logging.Log; 7#n<d879e%
import org.apache.commons.logging.LogFactory; J ytY6HF
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/** V:F;Nq%+j
* @author Joa w0QN5?
* 'Cy^G;
*/ /lAB
publicclass PageUtil { EtN@ 6xP
bc}X.IC
privatestaticfinal Log logger = LogFactory.getLog vW4~\]
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(PageUtil.class); 34VyR
a
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/** O+;0|4V%
* Use the origin page to create a new page jvx9b([<sG
* @param page J6x\_]1:*
* @param totalRecords "8K>Yu17
* @return R'a%_sACj>
*/ ;9r
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publicstatic Page createPage(Page page, int Q(SVJ
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totalRecords){ $>E\3npV
return createPage(page.getEveryPage(), "bZV<;y6
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page.getCurrentPage(), totalRecords); `x:znp} '
} Oq"(oNG@
e;b,7Qw
/** L(!4e
* the basic page utils not including exception iO=xx|d
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handler >}QRMn|@H
* @param everyPage w?CbATQ
* @param currentPage 2}j2Bhc
* @param totalRecords ={' "ATX(U
* @return page y7SOz'd
*/ :0o
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publicstatic Page createPage(int everyPage, int Z4FyuWc3
OJE<2:K
currentPage, int totalRecords){ :PtpIVAosg
everyPage = getEveryPage(everyPage); ^}; 4r
currentPage = getCurrentPage(currentPage); 0?uX}8w
int beginIndex = getBeginIndex(everyPage, xw: v|(
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currentPage); !mFo:nQ)}
int totalPage = getTotalPage(everyPage, J5L P#o(V
$mm =$.
totalRecords); n+@}8;oeP
boolean hasNextPage = hasNextPage(currentPage, g+/%r91hZ
!-
f>*|@
totalPage); JV'd!5P
boolean hasPrePage = hasPrePage(currentPage); /=Ug}%.
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returnnew Page(hasPrePage, hasNextPage, g!n1]- 1
everyPage, totalPage, ,oe
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currentPage, )gdv!
||
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beginIndex); 5A 1oZ+C#
} 2rHw5Wn]~
Wu)ATs}
privatestaticint getEveryPage(int everyPage){ "?,3O2t
return everyPage == 0 ? 10 : everyPage; FD(zj ^*
} =fMSmn1S
O{8"f\*
privatestaticint getCurrentPage(int currentPage){ zO{$kT\r&
return currentPage == 0 ? 1 : currentPage; )6)|PzMQ'
} `7jm
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privatestaticint getBeginIndex(int everyPage, int vl$! To9R"
Wm:3_C +j
currentPage){ Pb?H cg
return(currentPage - 1) * everyPage; Ku LZg
} wo2^,Y2z+
R#~}ZUk2
privatestaticint getTotalPage(int everyPage, int G B!3`
A%&
7HPLD&WPt
totalRecords){ k/l@P
int totalPage = 0; 4,9AoK)yp
7UHqiA`L
if(totalRecords % everyPage == 0) ?97MW a
totalPage = totalRecords / everyPage; %Hv$PsSJ
else aM 0kV.O
totalPage = totalRecords / everyPage + 1 ; <mHptgd,
L1BpkB
return totalPage; $}oQ=+c5
} e<5+&Cj
R+]p
-NI^
privatestaticboolean hasPrePage(int currentPage){ 80$P35Q"
return currentPage == 1 ? false : true; 9CJUOB>]
} Af=%5%
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privatestaticboolean hasNextPage(int currentPage, 3sGrX"0D
5!#"8|oY
int totalPage){ 7^sU/3z
return currentPage == totalPage || totalPage == WAY<X:|We
,2JqX>On>Y
0 ? false : true; ~m!>e])P?X
} qq-&z6;$
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} VR?7{3
<6<uO\B\
s
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X1<)B]y
js`zQx'
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。 JmNeqpbB`w
@usQ*k
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 B0p>' O2
}#!o^B8
做法如下: v ;MI*!E
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 _zh}%#6L
Oi
BK
的信息,和一个结果集List: {\|? {8f
java代码: yE9JMi0
6(9Ta'ywZ
lk.Q6saI1
/*Created on 2005-6-13*/ };o R x)
package com.adt.bo; zQ{ Q>"-
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import java.util.List; 5YS`v#+
vlIdi@V
import org.flyware.util.page.Page; mMN oR]
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/** EfDo%H^!j
* @author Joa :#TJ-l:#
*/ ,_NO[+5U
publicclass Result { 9Z*` {
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pW=G
private Page page; %h|z)
jLr8?Hyf
private List content; 4L!{U@'
IUd>jHp`6
/** A!^K:S:@
* The default constructor /bCrpcH
*/ YD@V2gK
public Result(){ tB(Q-c
super(); hph 3kfR
} Jq6p5jr"
W[^XG\
/** ac+7D:X
* The constructor using fields P]Gsc
* *\VQ%_wg
* @param page o\|dm."f
* @param content KD,b.s
*/ :@:R4Ac
public Result(Page page, List content){ Slv}6at5
this.page = page; ~fCD#D2KU
this.content = content; -HoPECe
}
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0@AK
/** $Z{ fKr
* @return Returns the content. )>\Ne~%
*/ ,?&hqM\
publicList getContent(){ (3]7[h7
return content; $Fr2oSTT)
} M8juab%y
|:!0`p{R
/** D<xP x
* @return Returns the page. U7PA%
*/ {qLnwy!i
public Page getPage(){ Mqc[IAcd]
return page; Kq{s^G
} ~ S-x-cZ
?WAlW,H>
/** [j93Mp
* @param content 0A 4(RLGg
* The content to set. @Wx_4LOhf
*/ dDpe$N
public void setContent(List content){ N#,4BU
this.content = content; Q;5\( 0w5
} $oxPmELtpe
(^Nf;E
/** + !_^MB kk
* @param page ;U20g:K
* The page to set. |;D[Al5AMc
*/ 55$by.rf?
publicvoid setPage(Page page){ ).ugMuk
this.page = page; R4IFl
z
}
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} a3O_8GU
~7~nU>Vv
i6X/`XW'
c7iu[vE'+
J=\Y 4- "
2. 编写业务逻辑接口,并实现它(UserManager, E0)v;yRcw
9 l,Gd
UserManagerImpl) p^L6uM
java代码: r`S]`&#}(
j ^_G
2iH,U
/*Created on 2005-7-15*/ .5dZaI)
package com.adt.service; e9%6+9Y
%djx0sy
import net.sf.hibernate.HibernateException; ! prU!5-
@'}X&TN<a
import org.flyware.util.page.Page; -TD6s:'
DJ<c
import com.adt.bo.Result; zZf#E@=$|
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/** G %#us3x
* @author Joa F5MWxAS,>
*/ s#d# *pgzh
publicinterface UserManager { ^
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n:#ji|wM
public Result listUser(Page page)throws Xp{gh@#dr
QPFpGS{d
HibernateException; !4 hs9b
@x=CMF15
} rBny*! n
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9s7B1Pf
0c3G_I=
lZ.,"F@
java代码: Q`//HOM,
H/L3w|2+
Z2$-},i
/*Created on 2005-7-15*/ +pFz&)?
package com.adt.service.impl; #);
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ZDVaKDqZ_
import java.util.List; .4^Paxz
8wy"m=>=b}
import net.sf.hibernate.HibernateException; ]7VK&YfN
/S;?M\
import org.flyware.util.page.Page; ?&X6VNbU
import org.flyware.util.page.PageUtil; sP+S86
u
XBr>K>(
import com.adt.bo.Result; z?gJHN<
import com.adt.dao.UserDAO; Zv-6H*zM6
import com.adt.exception.ObjectNotFoundException; FcWu#}.p}
import com.adt.service.UserManager; B[$SA-ZHi
Lte\;Se.tu
/** Awr]@%I
* @author Joa 5S7Z]DXiT8
*/ [wu%t8O2
publicclass UserManagerImpl implements UserManager { kh5V&%>?
d")r^7
private UserDAO userDAO; t*<c+Ixu
'rF TtT
/** 6XG+YIG6w
* @param userDAO The userDAO to set. PAc~p8S
*/ MRC5c:(
publicvoid setUserDAO(UserDAO userDAO){ ,>g
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this.userDAO = userDAO; .6'T;SoK>
} J`V6zGgW
3{c&%F~!
/* (non-Javadoc) *FAg^G&1
* @see com.adt.service.UserManager#listUser Ec[:6}
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(org.flyware.util.page.Page) ' 5Ieqpm9
*/ A9R}74e4g
public Result listUser(Page page)throws 3n/L;T,X
^{Vm,nAQqs
HibernateException, ObjectNotFoundException { cbteNA!>
int totalRecords = userDAO.getUserCount(); C9nNziws
if(totalRecords == 0) z^b\hR
throw new ObjectNotFoundException x``!t>)O
mb/3
#)
("userNotExist"); O^<6`ku
page = PageUtil.createPage(page, totalRecords); D{4
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List users = userDAO.getUserByPage(page); /;lk.-yU
returnnew Result(page, users); l9jcoVo.
} tT
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} bHMlh^{`%
fSP~~YSeU
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_<~05Eh
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 4 '+)9&g
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询,接下来编写UserDAO的代码: "s*{0'jo
3. UserDAO 和 UserDAOImpl: !kIw835U
java代码: eGE%c1H9a
hT_snb;ow
%z2nas$$g
/*Created on 2005-7-15*/ F+6ZD5/
package com.adt.dao; p!691LI
lfKknp#B/O
import java.util.List; ZHBwoC#5}
5 4OYAkPCk
import org.flyware.util.page.Page; PY2`RZ/ @
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q
import net.sf.hibernate.HibernateException; K1hw'AaQ
V4"AFArI
/** .dygp"*
* @author Joa 4a 5n*6G!
*/ :vr,@1c
publicinterface UserDAO extends BaseDAO { 226s:\d
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publicList getUserByName(String name)throws U!'lc}5
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HibernateException; =MXF`k^}
*K)v&}uw
publicint getUserCount()throws HibernateException; _ E%[D(
mSzwx/3"
publicList getUserByPage(Page page)throws :X!(^a;]
b^xf,`D
HibernateException; ~U1iB
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} <Kh\i'8
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JC#@sJ4az)
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G^R;~J*TDE
java代码: Cb13 Qz
)_=&)a1U
oY]VP+b!
/*Created on 2005-7-15*/ aw 7f$Fqk
package com.adt.dao.impl;
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lfA
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import java.util.List; ^DH*@M
cC[n~OV
import org.flyware.util.page.Page; <r kW4
RgO 7> T\
import net.sf.hibernate.HibernateException; {,
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import net.sf.hibernate.Query; `~}7k)F(
X=hgLK^3<,
import com.adt.dao.UserDAO; U\[V !1O
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/** R*y[/Aw
* @author Joa .~8+s.y
*/ :+5afv}
public class UserDAOImpl extends BaseDAOHibernateImpl gv,T<A?Z2
c,qCZ-.Sg
implements UserDAO { )k1,oUx
\XN5))
/* (non-Javadoc) $7r
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* @see com.adt.dao.UserDAO#getUserByName `SW
" RLS3
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(java.lang.String) KFhn}C3
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*/ YfalsQ8
publicList getUserByName(String name)throws q!TbM"
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HibernateException { s,k1KTXg<B
String querySentence = "FROM user in class IX(yajc[~M
HLk"a-+'
com.adt.po.User WHERE user.name=:name"; aC},h
Query query = getSession().createQuery S3'g(+S
Z:hrrq9
(querySentence); hq*JQb;Y}
query.setParameter("name", name); \,EPsQV0?
return query.list(); 9H}&Ri%
} Z)A+ wM
_HK&KY
/* (non-Javadoc) 8?YW i
* @see com.adt.dao.UserDAO#getUserCount() `|w#K28t"
*/ v6VhXV6$|
publicint getUserCount()throws HibernateException { J){\h-4
int count = 0; `Y;gMrp
String querySentence = "SELECT count(*) FROM \k=Qq(=
wUeOD.;#F
user in class com.adt.po.User"; |BkY"F7m9
Query query = getSession().createQuery IpJ v\zH7
O)|4>J*B
(querySentence); I`TD*D
count = ((Integer)query.iterate().next !S!03|
@qDrTH]5
()).intValue(); 4sQAR6_SW~
return count; {?y7'
} +E~`H^
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/* (non-Javadoc) WS/+Yl
* @see com.adt.dao.UserDAO#getUserByPage %`1vIr(7
ewG21 q$
(org.flyware.util.page.Page) h /QP=Zd
*/ ug,|'<G+
publicList getUserByPage(Page page)throws D:E_h
;QQ7vo
HibernateException { 5#)<rK
String querySentence = "FROM user in class HdUW(FZ
yTt (fn:;
com.adt.po.User"; ->&VbR)
Query query = getSession().createQuery ~k0)+D}
*F*fH>?C#
(querySentence); b6Hk20+B;
query.setFirstResult(page.getBeginIndex()) <M?#3&5A
.setMaxResults(page.getEveryPage()); Pu*HZW3l
return query.list(); 8VmN?"5v
} 1!wEXH(
{l&2Kd*
} %QgAilj,
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=k=2~
j
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pf@}4PN}
至此,一个完整的分页程序完成。前台的只需要调用 (y=o]Vy
FTnQqDuT
userManager.listUser(page)即可得到一个Page对象和结果集对象 [0ffOTy
><MgIV
的综合体,而传入的参数page对象则可以由前台传入,如果用 Gy6qLM
6xIYg ^
webwork,甚至可以直接在配置文件中指定。 _`{{39 F
5b`xN!c
下面给出一个webwork调用示例: 25c!-.5D
java代码: .0E4c8R\X
R(83E
B~_
nvK7*-
/*Created on 2005-6-17*/ <`_OpNxqW
package com.adt.action.user; K_|~3g
yLO
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import java.util.List; :@`(}5F4
s|j<b#<xQ
import org.apache.commons.logging.Log; E9B*K2l^{
import org.apache.commons.logging.LogFactory; ;3}EBcw)
import org.flyware.util.page.Page; H
L|spl(c
? < O
import com.adt.bo.Result; pb6^sA%l
import com.adt.service.UserService; `vxrC&,As
import com.opensymphony.xwork.Action; kqvJ&7
N%rL=zE
/** FgQ_a/*
* @author Joa fk7Cf"[w
*/ NZC='3Uz
publicclass ListUser implementsAction{ @Du}
Y`7#[g
privatestaticfinal Log logger = LogFactory.getLog #!Cter2
#G+
(ListUser.class); L^Q+Q)zTh
,Q=)$ `%
private UserService userService; Eh@T W%9*
k\c &2T]W
private Page page; EcU'*
-iDEh_pts
privateList users; b({Nf,(a2
;IuK2iDt<
/* CxA\yG3L&
* (non-Javadoc) 7vpN6YP
* k g,ys4
* @see com.opensymphony.xwork.Action#execute() hHc^ZA
*/ RQpIBsj
publicString execute()throwsException{ 2WPF{y%/
Result result = userService.listUser(page); TjUZv 1(L
page = result.getPage(); fAMD2C
users = result.getContent(); ,B~lwF9
return SUCCESS; QI#*5zm
} (}FW])y
V4eng "
/** v*H &