Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 cUc:^wvLS
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 KN"<f:u
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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 "E%3q 3|"l
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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 0'~Iv\s
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分页支持类: _/cL"Wf
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java代码: n_@cjO
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package com.javaeye.common.util; dmk_xBy s|
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import java.util.List; >PONu]^
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publicclass PaginationSupport { 5yQ\s[;o3
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publicfinalstaticint PAGESIZE = 30; n+:}pD
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privateint pageSize = PAGESIZE; ~oE@y6Q
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privateList items; v7G&`4~
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privateint totalCount; Gey j`t
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privateint[] indexes = newint[0]; hO0g3^
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privateint startIndex = 0; S F&EVRv
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public PaginationSupport(List items, int v `7` '
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totalCount){ Z^r?
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setPageSize(PAGESIZE); rxQ&N[r2
setTotalCount(totalCount); d{:0R9
setItems(items); &~#y-o"
setStartIndex(0); o6A1;e
} ^>m"j6`h,
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public PaginationSupport(List items, int jRNDi_u?Wb
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totalCount, int startIndex){ eD?f|bif
setPageSize(PAGESIZE); &AhkP=Yw
setTotalCount(totalCount); zHk7!|%Y
setItems(items); TI}Y U
setStartIndex(startIndex); q@Oe}
} *PF=dx<8
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public PaginationSupport(List items, int g<PglRr"
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totalCount, int pageSize, int startIndex){ 2^4OaHY88
setPageSize(pageSize); )l[bu6bM
setTotalCount(totalCount); g0>Q* x
setItems(items); 98LyzF9
setStartIndex(startIndex); :C9vs
} \TnRn(Kw
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publicList getItems(){ wi@Qf6(mn
return items; 'rDai[
} :FX|9h
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publicvoid setItems(List items){ a+PVi
this.items = items; K | '`w.
} W+u-M>Cj6
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publicint getPageSize(){ 5Sz}gP('
return pageSize;
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} gt)wk93d>
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publicvoid setPageSize(int pageSize){ #gSLFM{p
this.pageSize = pageSize; #9CLIYJAd
} G*%:"qleT$
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publicint getTotalCount(){ `PS>"-AY2
return totalCount; w'7=CzfYn
} 5Sx.'o$
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publicvoid setTotalCount(int totalCount){ lL"ANlX-P
if(totalCount > 0){ ki'CW4x
this.totalCount = totalCount; /a?qtRw
int count = totalCount / -~v1@
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pageSize; ndS8p]P&o(
if(totalCount % pageSize > 0) /MZ^;XG
count++; Ri;_
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indexes = newint[count]; *=zv:!
for(int i = 0; i < count; i++){ ch]{=61
indexes = pageSize * jH?!\F2)+
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} 5[Uv%A?H#_
}else{ \h5!u1{L
this.totalCount = 0; B/Z-Cpz]
} D-4{9[
} 'b:e8m
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publicint[] getIndexes(){ AA<QI' 6
return indexes; JasA
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} ]-cSTtO
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publicvoid setIndexes(int[] indexes){ !!d?o
this.indexes = indexes; DT vCx6:!
} cG,zO-H
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publicint getStartIndex(){ fi [4F
return startIndex; vX|5*T`(
} ZaF9Q%
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publicvoid setStartIndex(int startIndex){ <h%I-e6
if(totalCount <= 0) 0t7vg#v|
this.startIndex = 0; Z7p!YTA
elseif(startIndex >= totalCount) 8\Bb7*
this.startIndex = indexes K/M2L&C
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[indexes.length - 1]; '
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elseif(startIndex < 0) .?kq\.rQ
this.startIndex = 0; vn4z C
else{ V6Y0#sTU
this.startIndex = indexes CD[}|N
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[startIndex / pageSize]; <nc6&+
} vwAtX($
} u6SQq-)d
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publicint getNextIndex(){ *USG
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int nextIndex = getStartIndex() + fwNj@fl_,e
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pageSize; 8kT`5`}lB
if(nextIndex >= totalCount) U1O8u -X
return getStartIndex(); vUhgM'
else GglGFXOL-
return nextIndex; 45rG\$%#
} t~|J2*9l
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publicint getPreviousIndex(){ f$ 7C 5
int previousIndex = getStartIndex() - qHnX)
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pageSize; 1Eb2X}XC
if(previousIndex < 0) b8E7/~<z3
return0; Bk[C=< X
else 0+e
return previousIndex; e,
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} Kr;;aT0P
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} e~7FK_y#0
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抽象业务类 .3&(Y
java代码: ")<5VtV
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/** inh
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* Created on 2005-7-12 A9;,y'm^8
*/ $O%"[w
package com.javaeye.common.business; sou~m,#
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import java.io.Serializable; O]'2<;
import java.util.List; RL3*fRlb
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import org.hibernate.Criteria; .><-XJ
import org.hibernate.HibernateException; D -d
import org.hibernate.Session; x#gZC1$Y
import org.hibernate.criterion.DetachedCriteria; fUr%@&~l^
import org.hibernate.criterion.Projections; <@P. 'rE
import LosRjvQ:
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org.springframework.orm.hibernate3.HibernateCallback; XJ5@/BW
import '6;
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org.springframework.orm.hibernate3.support.HibernateDaoS \*[DR R0
vn!5@""T
upport; hQ'W7EF
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import com.javaeye.common.util.PaginationSupport; +abb[
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public abstract class AbstractManager extends .+kg1=s
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HibernateDaoSupport { 4XAs^>N+
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privateboolean cacheQueries = false; D|ra ;d
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privateString queryCacheRegion; ;dPaWS1D
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publicvoid setCacheQueries(boolean g9fYt&
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cacheQueries){ D<|$ZuB4
this.cacheQueries = cacheQueries; XRO(p`OE-
} < Sgc6>)
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publicvoid setQueryCacheRegion(String 6~Dyr82"B
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queryCacheRegion){ Yxbg _RQm
this.queryCacheRegion = T*%rhnTv0
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queryCacheRegion; r}es_9*~Z
} ?|98Y"w
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publicvoid save(finalObject entity){ M[~{!0Uz
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getHibernateTemplate().save(entity); P;o{t
} JsNj!aeU%
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publicvoid persist(finalObject entity){ 1y\bJ
getHibernateTemplate().save(entity); 3&CV!+z
} OTE,OCB[
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publicvoid update(finalObject entity){
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getHibernateTemplate().update(entity); zyhM*eM.7
} oyr b.lu/
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publicvoid delete(finalObject entity){ o$eCd{HuX
getHibernateTemplate().delete(entity); : NA(nA
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} 3UaW+@
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publicObject load(finalClass entity, qxDMDMN
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finalSerializable id){ Hy1$Kvub
return getHibernateTemplate().load AH :uG#
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(entity, id); f;Oh"Yt
} Zp^O1&\SK?
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publicObject get(finalClass entity, !Ve0 :$
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finalSerializable id){ 1Acs0`3
return getHibernateTemplate().get tsL
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(entity, id); ^8_yJ=~V
} n1{[CCee@
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publicList findAll(finalClass entity){ 4>i\r
return getHibernateTemplate().find("from =\|,hg)c
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" + entity.getName()); =PciLh
} C\;l)h_{
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publicList findByNamedQuery(finalString icIn>i<m
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namedQuery){ nq HpYb6I0
return getHibernateTemplate {0w2K82
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().findByNamedQuery(namedQuery); @fYVlHT%E
} g(9* !g
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publicList findByNamedQuery(finalString query, Ht4O5yl"
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finalObject parameter){ '(FC
return getHibernateTemplate IycZ\^5 *-
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().findByNamedQuery(query, parameter); `
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} .Y{x!Q"
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publicList findByNamedQuery(finalString query, \Q(a`6U
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finalObject[] parameters){ lYCvYe
return getHibernateTemplate -f&vH_eK
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().findByNamedQuery(query, parameters); 4pf@.ra,
} 0t%]z!
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publicList find(finalString query){ w(&EZDe
return getHibernateTemplate().find Jh 0Grq
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(query); mf$YsvPq*+
} YB7n}r23
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publicList find(finalString query, finalObject RW+u5Y
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parameter){ :Q> e54]'&
return getHibernateTemplate().find p$9Aadi]
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(query, parameter); 6vsA8u(|V#
} eZAMV/]jH
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public PaginationSupport findPageByCriteria TT/H"Ri}Jp
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(final DetachedCriteria detachedCriteria){ QF/_?Tm4
return findPageByCriteria M%`CzCL
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); sFz0:SqhE
} `
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public PaginationSupport findPageByCriteria %S;AM\o4
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(final DetachedCriteria detachedCriteria, finalint x)Bbo9J
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startIndex){ 2P^|juc)sU
return findPageByCriteria s{Qae=$Q
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(detachedCriteria, PaginationSupport.PAGESIZE, up'`)s'
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startIndex); __'4Qt
} uL^; i""
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public PaginationSupport findPageByCriteria cl4z%qv*
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(final DetachedCriteria detachedCriteria, finalint ^#<L!yo^
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pageSize, KJ'ID
finalint startIndex){ mG\QF0h
return(PaginationSupport) 'G l~P><e
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getHibernateTemplate().execute(new HibernateCallback(){ `^SRg_rH=`
publicObject doInHibernate P-Y_$Nv0g
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(Session session)throws HibernateException { e9{0hw7
Criteria criteria = BA:x*(%~
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detachedCriteria.getExecutableCriteria(session); #j~FlY5
int totalCount = }8x+F2i
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((Integer) criteria.setProjection(Projections.rowCount VQHB}Y@^
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()).uniqueResult()).intValue(); Sc[#]2 }
criteria.setProjection s)]j X
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(null); tJ6@Ot
List items = J;>epM;*
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criteria.setFirstResult(startIndex).setMaxResults =4eJ@EVM
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(pageSize).list(); !l0]IX`
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PaginationSupport ps = Jx.fDVJ
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new PaginationSupport(items, totalCount, pageSize, 3@I0j/1#k1
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startIndex); pNb2t/8%%
return ps; Sk|e#{
} )*]A$\Oc[
}, true); R7Y_ 7@p
} x8rg/y
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public List findAllByCriteria(final WT ;2aS:
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DetachedCriteria detachedCriteria){ r&E gP
return(List) getHibernateTemplate =%7drBo D
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().execute(new HibernateCallback(){
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publicObject doInHibernate ~-zTY&c_
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(Session session)throws HibernateException { NbU`_^oC
Criteria criteria = 2L](4Q[M
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detachedCriteria.getExecutableCriteria(session); <}RI<96
return criteria.list(); n>ui'}L
} TF/NA\0c$
}, true); U*r54AyP
} }pMVl
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public int getCountByCriteria(final .kBkYK8*t
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DetachedCriteria detachedCriteria){ M
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Integer count = (Integer) h~ k<"
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getHibernateTemplate().execute(new HibernateCallback(){ \l:R]:w;ZI
publicObject doInHibernate <==uK>pET
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(Session session)throws HibernateException { l/G+Xj4M
Criteria criteria = dxs5woP
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detachedCriteria.getExecutableCriteria(session); s-"KABEE
return _Z0 .c@0
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criteria.setProjection(Projections.rowCount `MI;.t
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()).uniqueResult(); g{]6*`/Z
} #%;Uh
}, true); Nu"v
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return count.intValue(); |eu8;~A
} ytIPY7E
} oVpZR$
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用户在web层构造查询条件detachedCriteria,和可选的 "bhK%N;
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [K3
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PaginationSupport的实例ps。 F\DiT|?}
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ps.getItems()得到已分页好的结果集 C .S BJ
ps.getIndexes()得到分页索引的数组 d0 )725Ia
ps.getTotalCount()得到总结果数
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ps.getStartIndex()当前分页索引 nc;eNB
ps.getNextIndex()下一页索引 C1D:Xi-
ps.getPreviousIndex()上一页索引 y47N(;vy
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 wo0j/4o
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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 \t!~s^ Oox
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一下代码重构了。 7% D 4
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我把原本我的做法也提供出来供大家讨论吧: oy8jc];SO
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首先,为了实现分页查询,我封装了一个Page类: Q7aPW\-
java代码: Jo {:]:
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/*Created on 2005-4-14*/ N#ggT9>X
package org.flyware.util.page; FLW VI4*
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/** QJ XP-
* @author Joa <<0sv9qw1
* \\k=N(n
*/ <Z%=lwtX
publicclass Page { ,\6Vb*G|E>
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/** imply if the page has previous page */ G`FYEmD
privateboolean hasPrePage; I}_}VSG(
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/** imply if the page has next page */ vIRT$W' O}
privateboolean hasNextPage; fxd+0R;f
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/** the number of every page */ 9f!
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privateint everyPage; ~$u9
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/** the total page number */ g=t`3X#d
privateint totalPage; v'i'I/
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/** the number of current page */ T01Iu
privateint currentPage; I0+6p8,
8* A%k1+
/** the begin index of the records by the current v@=qVwX
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query */ ,>-j Ztm
privateint beginIndex; !h.hJt
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/** The default constructor */ 8oJl ]
public Page(){ [#Qf#T%5h
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} G[>NP#P
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/** construct the page by everyPage 1d< b\P0
* @param everyPage %6 *c40
* */ Z<;W*6J
public Page(int everyPage){ N
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this.everyPage = everyPage; ~2Wus8X-
} #Nh'1@@
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/** The whole constructor */ -Rpra0o.
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public Page(boolean hasPrePage, boolean hasNextPage, <