Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 |C;=-|
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 G\/zkrxmv
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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 V%7WUq
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分页支持类: =1FRFZI!j
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java代码: Uu10)/.LC
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package com.javaeye.common.util; [i21FX
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import java.util.List; L:KF_W.I+
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publicclass PaginationSupport { >a!/QMh
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publicfinalstaticint PAGESIZE = 30; q~b&
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privateint pageSize = PAGESIZE; |sJ[0z
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privateList items; y2Q&s9$Do
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privateint totalCount; d\&U*=
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privateint[] indexes = newint[0]; Dzpq_F!;V
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privateint startIndex = 0; SB;&GHq"n
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public PaginationSupport(List items, int }/0X'o
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totalCount){ j"t(0m
setPageSize(PAGESIZE); WrnrFz
setTotalCount(totalCount); ^H p; .f.
setItems(items); .wEd"A&j
setStartIndex(0); *<$*"p
} SXSgld2uS
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public PaginationSupport(List items, int & TCkpS
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totalCount, int startIndex){ }kw#7m54
setPageSize(PAGESIZE); wjU9ZGM
setTotalCount(totalCount); GL>O4S<`
setItems(items); afCW(zHp
setStartIndex(startIndex); / H[=5
} Hck]aKI+
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public PaginationSupport(List items, int a(m2n.0'>
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totalCount, int pageSize, int startIndex){ 3H'sHuK"X
setPageSize(pageSize); k%]3vRo<
setTotalCount(totalCount); iQ0KfoG?U
setItems(items); aG-vtld
setStartIndex(startIndex); $f$SNx)),
} f%A;`4`q
n QF(vTDN
publicList getItems(){ %e8@*~h@
return items; ]vB$~3||
} pE3?"YO
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publicvoid setItems(List items){ ^)470K`%)
this.items = items; /`Ug9,*
} 7zl5yKN
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publicint getPageSize(){ v8w q,CYV
return pageSize; vRYQ{:
} mtpeRVcF
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publicvoid setPageSize(int pageSize){ <jBF[v9*m(
this.pageSize = pageSize; +i6GHBn~J
} (=FRmdeYl1
1>.Ev,X+e
publicint getTotalCount(){ VnSCz" ?3
return totalCount; P7ao5NP
} 3#n_?-
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publicvoid setTotalCount(int totalCount){ kl"hBK#D%
if(totalCount > 0){ "-Mp_O]
this.totalCount = totalCount; =?5]()'*n
int count = totalCount / w$>u b@=
8:q1~`?5"b
pageSize; (Nq=H)cm8
if(totalCount % pageSize > 0) p
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count++; #]-SJWf3
indexes = newint[count]; ;'gWu
for(int i = 0; i < count; i++){ xW+6qtG`
indexes = pageSize * 9V a}I-
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i; ^23~ZHu
} m%0p\Y-/
}else{ I<DL=V
this.totalCount = 0; 7:e{;iG
} ynp 8rf
} YByLoM*
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publicint[] getIndexes(){ V~qNyOtA]
return indexes; ~\r*
} HGl|-nW>
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publicvoid setIndexes(int[] indexes){ \a<wKTkn
this.indexes = indexes; a1+oj7
} |o7[|3:M
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publicint getStartIndex(){ UklUw
return startIndex; D=TvYe
} O/^%2mG
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publicvoid setStartIndex(int startIndex){ >:SHV W
if(totalCount <= 0) PhLn8jNti
this.startIndex = 0; Q(G#W+r
elseif(startIndex >= totalCount) pt?bWyKG
this.startIndex = indexes NCveSP
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[indexes.length - 1]; -+-?w|}qV
elseif(startIndex < 0) YH$-g
this.startIndex = 0; 53_Hl]#qZ
else{ 7K12 G!)
this.startIndex = indexes }f%} v
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[startIndex / pageSize]; `Uq#W+r,
} aNsBcov3O
} O}gV`q;
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publicint getNextIndex(){ eNh39er
int nextIndex = getStartIndex() + ^+ml5m
t6rRU~;}
pageSize; KA5v +~
if(nextIndex >= totalCount) m5n#v
return getStartIndex(); qyb?49I
else H;mSkRD3N
return nextIndex; VD AaYDi
} "37lx;CH
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publicint getPreviousIndex(){ /*~EO{o
int previousIndex = getStartIndex() - $B+8Of
Q) #B0NA;T
pageSize; SZ7:u895E
if(previousIndex < 0) ME$[=?7XX
return0; m<G,[Yc
else je\Ph5 "
return previousIndex; S
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} 2F;y;l%
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} _{ue8kGt
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抽象业务类 Z9E\,Ly
java代码: >dXGee>'M
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/** krxo"WgD
* Created on 2005-7-12 W.jGGt\<\
*/ $QF{iV@6d4
package com.javaeye.common.business; ,oe <
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import java.io.Serializable; hR
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import java.util.List; ~hH REI&
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import org.hibernate.Criteria; ITQA0PISL
import org.hibernate.HibernateException; G't$Qx,IC
import org.hibernate.Session; ;O5zUl-`
import org.hibernate.criterion.DetachedCriteria; }Bh8=F3O
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import org.hibernate.criterion.Projections; + 480 l}
import )m+W
j
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org.springframework.orm.hibernate3.HibernateCallback; FXCMR\BsQ
import ~At7 +F[
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org.springframework.orm.hibernate3.support.HibernateDaoS :G=fl)!fE
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upport; s[*rzoA
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import com.javaeye.common.util.PaginationSupport; s)t@ol
@;4zrzQi7
public abstract class AbstractManager extends EWt[z.`T1
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HibernateDaoSupport { n6>#/eUH
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privateboolean cacheQueries = false; Jr4Ky<G_i
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privateString queryCacheRegion; B@))8.h]
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publicvoid setCacheQueries(boolean QL/(72K
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cacheQueries){ U>SShpmZA
this.cacheQueries = cacheQueries; Vt~{Gu-Y
} Pm?KI<TH~
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publicvoid setQueryCacheRegion(String `[yKFa
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queryCacheRegion){ fbvL7*
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this.queryCacheRegion = /s?`&1v|r
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queryCacheRegion; VGN5<?PrN
} !|uWH
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publicvoid save(finalObject entity){ Uc>lGo1j
getHibernateTemplate().save(entity); $wa{~'
} Vp\,CuQ
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publicvoid persist(finalObject entity){ ^DLfY-F+j
getHibernateTemplate().save(entity); 6|=f$a
} QIEJ6`
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publicvoid update(finalObject entity){ W@IQ^
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getHibernateTemplate().update(entity); ,qwuLBW
} R\f+SvE
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publicvoid delete(finalObject entity){ H8jpxzXv
getHibernateTemplate().delete(entity); 1GRCV8"Z^
} !BF;
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publicObject load(finalClass entity, >Tx?%nQ
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finalSerializable id){ |e&\<LwsP
return getHibernateTemplate().load /nsX]V6i
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(entity, id); r5/0u(\LB
} T>Z<]s
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publicObject get(finalClass entity, WU`
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finalSerializable id){ 6MW{,N
return getHibernateTemplate().get ajT*/L!0_
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(entity, id); @mBQ?;qlK
} Y=KT eYW`
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publicList findAll(finalClass entity){ $PPi5f}HD
return getHibernateTemplate().find("from Zi
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" + entity.getName()); b|DdG/O
} JbbzV>
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publicList findByNamedQuery(finalString qDIZJh
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namedQuery){ =nS3p6>rZ
return getHibernateTemplate #!#
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().findByNamedQuery(namedQuery); N+xP26D8
} WH} y"W
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publicList findByNamedQuery(finalString query, SfyQ$$Z
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finalObject parameter){ 'H!Uh]!
return getHibernateTemplate EVSX.'&f
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().findByNamedQuery(query, parameter); _{KG
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} ND;#7/$>
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publicList findByNamedQuery(finalString query, 7}>E J
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finalObject[] parameters){ t*u:hex
return getHibernateTemplate +6\Zj)
# W']6'O
().findByNamedQuery(query, parameters); 0S~rgq|O
} ~0$&3a<n1
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publicList find(finalString query){
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return getHibernateTemplate().find (A#^l=su
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(query); eauF~md,
} 0h_|t-9j
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publicList find(finalString query, finalObject `;C V=,M
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parameter){ L4HI0Mx
return getHibernateTemplate().find /4Gt{ygSr
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(query, parameter); ~>|ziHx
} .q>iXE_c
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public PaginationSupport findPageByCriteria bAMdI 5Zk?
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(final DetachedCriteria detachedCriteria){ |{ip T SH
return findPageByCriteria C6PdDRf
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 1+s;FJ2}
} sgFEK[w.y
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public PaginationSupport findPageByCriteria *2l7f`K
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(final DetachedCriteria detachedCriteria, finalint hgq;`_;1,
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startIndex){ qE"OB
return findPageByCriteria <5051UEu
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(detachedCriteria, PaginationSupport.PAGESIZE, ;V!D:5U
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startIndex); }K(TjZR
} &D<y X~
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public PaginationSupport findPageByCriteria !a\^Sk
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(final DetachedCriteria detachedCriteria, finalint Bzf^ivT3L
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pageSize, i
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finalint startIndex){ H5|;{q:j
return(PaginationSupport) Pm7}"D'/
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getHibernateTemplate().execute(new HibernateCallback(){ :2`e(+Uz
publicObject doInHibernate ,P0) 6>
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(Session session)throws HibernateException { :ws<-Qy
Criteria criteria = (bS&D/N.
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detachedCriteria.getExecutableCriteria(session); 3v-~K)hl?
int totalCount = *;FdD{+
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((Integer) criteria.setProjection(Projections.rowCount (ZlU^Gw#UB
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()).uniqueResult()).intValue(); Ewz!O`
criteria.setProjection %hP^%'G
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(null); .%-8 t{dt
List items = c+ie8Q!
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criteria.setFirstResult(startIndex).setMaxResults BgT*icd8d
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(pageSize).list(); !4!~Lk=
PaginationSupport ps = ;tf=gdX;
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new PaginationSupport(items, totalCount, pageSize, EU#^7
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startIndex); !G|@6W`
return ps; 7tp36 TE
} 3so%gvY.'
}, true); l]SX@zTb
}
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public List findAllByCriteria(final zQ PQ
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DetachedCriteria detachedCriteria){ fP1!)po
return(List) getHibernateTemplate :4|4 =mkr
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().execute(new HibernateCallback(){ XWw804ir
publicObject doInHibernate +ZV5o&V>
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(Session session)throws HibernateException { -?a 26o%e
Criteria criteria = ]M3yLYK/P
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detachedCriteria.getExecutableCriteria(session); U0+-W07>
return criteria.list(); ,zc(t<|-y
} V]^$S"Tv
}, true); X8\GzNE~R
} An@t?#4gxi
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public int getCountByCriteria(final 7HWmCaa[
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DetachedCriteria detachedCriteria){ v@pky0
Integer count = (Integer) 2AdDIVYC
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getHibernateTemplate().execute(new HibernateCallback(){ unxqkU/<Z
publicObject doInHibernate ]$hBMuUa
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(Session session)throws HibernateException { "N#Y gSr
Criteria criteria = 8Fub<UhJ
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detachedCriteria.getExecutableCriteria(session); Y:`&=wjP~
return i#O SC5ZI
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criteria.setProjection(Projections.rowCount 'ga/
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()).uniqueResult(); vQ.R{!",>
} EM_d8o)`B
}, true); gM]:Ma
return count.intValue(); Y-9I3?ar
} c@Is2
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} (k P9hcV
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用户在web层构造查询条件detachedCriteria,和可选的 zm# ?W
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Ul# r
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PaginationSupport的实例ps。 n+p }\msH
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ps.getItems()得到已分页好的结果集 XP}<N&j
ps.getIndexes()得到分页索引的数组 +|f@^-
ps.getTotalCount()得到总结果数 YYS0`
ps.getStartIndex()当前分页索引 O0:q;<>z
ps.getNextIndex()下一页索引 |BYRe1l6l
ps.getPreviousIndex()上一页索引 #K&Gp-
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 A(X KyEx
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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 /V By^ L:
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一下代码重构了。 sRfcF`7
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我把原本我的做法也提供出来供大家讨论吧: }a/Cro.~4
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首先,为了实现分页查询,我封装了一个Page类: M\=2uKG#
java代码: ,u m|1dh
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/*Created on 2005-4-14*/ 2zpr~cB=
package org.flyware.util.page; DwF hK*
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/** <N@Gu!N8
* @author Joa *ui</+
* 6B-16
*/ Y*hCMy;
publicclass Page { h];I{crh
2SLU:=<3
/** imply if the page has previous page */ rlD8D|ZG
privateboolean hasPrePage; L(\cH b9`
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/** imply if the page has next page */ ce(#2o&`
privateboolean hasNextPage; P;*(hY5&
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/** the number of every page */
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privateint everyPage; p[cX O=
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/** the total page number */ $!DpjN
privateint totalPage; @ P|y{e6
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/** the number of current page */ EV?z`jE9
privateint currentPage; j.YA2mr
n`KY9[0U=
/** the begin index of the records by the current @pxcpXCy
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query */ I_BJH'!t
privateint beginIndex; ~s{$WL&
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/** The default constructor */ 7o4\oRGV
public Page(){ '<M{)?
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} Wjc'*QCPl
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/** construct the page by everyPage ElXFeJ%[G
* @param everyPage s @C}P
* */ w>YDNOk
public Page(int everyPage){ YS ][n_
this.everyPage = everyPage; qWw=8Bq
} o(HbGHIP
Y ay?=Y{
/** The whole constructor */ Mfs?x
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public Page(boolean hasPrePage, boolean hasNextPage, N;gfbh]
;\]@K6m/Ap
#1[u(<AS
int everyPage, int totalPage, =QsYXK7Mn4
int currentPage, int beginIndex){ o}!PQ#`M
this.hasPrePage = hasPrePage; cu6Opq9
this.hasNextPage = hasNextPage; ry!!9Z>9n
this.everyPage = everyPage; T;uX4,|(
this.totalPage = totalPage; 6nQq
this.currentPage = currentPage; +q oRP2
this.beginIndex = beginIndex; n| ;Im&,
} ~m |BC*)
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/** 626r^c=
* @return rGO8!X 3d
* Returns the beginIndex. ]?*wbxU0
*/ 7 3m1
publicint getBeginIndex(){ f<H2-(m
return beginIndex; yjAL\U7`T
} 8_8l.!~
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/** ^s=8!=A(
* @param beginIndex L$-T,Kze
* The beginIndex to set. PM+[,H
*/ =}*0-\QG
publicvoid setBeginIndex(int beginIndex){ <qSC#[xu
this.beginIndex = beginIndex; OYd !v`<
} `]X>V,
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/** YMgNzu
* @return G?ZXWu.
* Returns the currentPage. ;fJ.8C
*/ Ib`XT0k
publicint getCurrentPage(){ ! z**y}<T
return currentPage; P'2Qen*
} E3i4=!Y
w &(ag$p'
/** ,^:.dFH6
* @param currentPage [~^0gAlQC
* The currentPage to set. i$@:@&(~Y
*/ G#CXs:1pd+
publicvoid setCurrentPage(int currentPage){ liZxBs
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this.currentPage = currentPage; q@&6#B
} J1vR5wbu
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/** G"6 !{4g
* @return O}P`P'Y|'
* Returns the everyPage. OPi0~s
*/ $Y;RKe9
publicint getEveryPage(){ U17d>]ka
return everyPage; yr6V3],Tp
} "zc l|@
R=dC4;
/** <[v[ci
* @param everyPage %RVZD#zr
* The everyPage to set. y(&Ac[foS}
*/ 6mE\OS-I
publicvoid setEveryPage(int everyPage){ y2v^-q3
this.everyPage = everyPage; _&x%^&{
} C}X\|J
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/** qLCR] _*
* @return C+]I@Go'Tk
* Returns the hasNextPage. !<oe=)Iz|
*/ TseGXYH
publicboolean getHasNextPage(){ [Zrr)8A
return hasNextPage; %)|s1B'd
} @co
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/** *_e3 @g
* @param hasNextPage >usL*b0%
* The hasNextPage to set. =v\.h=~~
*/ ':q p05t
publicvoid setHasNextPage(boolean hasNextPage){ 5s XXM
this.hasNextPage = hasNextPage; 9$Y=orpWxr
} fOHxtHM
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/** jylD6IT
* @return :DNjhZ
* Returns the hasPrePage. $:6!H:ty
*/ D=$)n_F
publicboolean getHasPrePage(){ #z(]xI)"
return hasPrePage; *hrvYil2b
} .X&9Q9T=#
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/** 3'Rx=G'
* @param hasPrePage I'Hf{Erw
* The hasPrePage to set. #G3<7PK
*/ ta0|^KAA
publicvoid setHasPrePage(boolean hasPrePage){ xG 1nGO
this.hasPrePage = hasPrePage; [WJ+h~~
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} FwK]$4*
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/** rjP/l6
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* @return Returns the totalPage. 0_/[k*Re
* V+\Wb[zDJ
*/ d5b%
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publicint getTotalPage(){ N[hG8f
return totalPage; QPx^_jA
} k+/6$pI
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/** yauvXosX
* @param totalPage LD?sh"?b
* The totalPage to set. l] vm=7:
*/ +_!QSU,@
publicvoid setTotalPage(int totalPage){ \wZe] G%S
this.totalPage = totalPage; bD^owa
} TpaInXR
K"6vXv4QO
} iscz}E,Y
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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 $qiya[&G4
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个PageUtil,负责对Page对象进行构造: VTM/hJmwJ
java代码: +q4O D$}
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/*Created on 2005-4-14*/ wkq 66?
package org.flyware.util.page; baasGa3}s
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import org.apache.commons.logging.Log; hgmCRC
import org.apache.commons.logging.LogFactory; W^Yxny
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/** .`lCWeHN
* @author Joa 6863xOv{T
* 1oS/`)
*/ h8P)%p
publicclass PageUtil { M}a6Vu9
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privatestaticfinal Log logger = LogFactory.getLog 0sqFF[i
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(PageUtil.class); ^~dWU>
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/** dM5-;
* Use the origin page to create a new page 7_L;E~\
* @param page RN1_S
* @param totalRecords ig!+2g
* @return _#niyW+?~
*/ do%&m]#;
publicstatic Page createPage(Page page, int eRYK3W
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totalRecords){ _-D{-Bu#
return createPage(page.getEveryPage(), uZ5p#M_
+z( Lr=G
page.getCurrentPage(), totalRecords); #R"*c
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} eavV?\uV%
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/** |=w@H]r
* the basic page utils not including exception f 2.HF@
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handler &&+H+{_Q
* @param everyPage Ey2^?
* @param currentPage 'V {W-W<
* @param totalRecords QY/w
* @return page %{|p j
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*/ \<' ?8ri#
publicstatic Page createPage(int everyPage, int L#J1b!D&<6
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currentPage, int totalRecords){ \Z/@C lCm
everyPage = getEveryPage(everyPage); s#11FfF`
currentPage = getCurrentPage(currentPage); n[z+<VGwC
int beginIndex = getBeginIndex(everyPage, Z~CjA%l
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currentPage); JI}'dU>*U:
int totalPage = getTotalPage(everyPage, 3$ pX
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totalRecords); %Zi} MPx
boolean hasNextPage = hasNextPage(currentPage, $I=~S[p
nKY6[|!#
totalPage); xEI%D|)<
boolean hasPrePage = hasPrePage(currentPage); 0;k# *#w
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returnnew Page(hasPrePage, hasNextPage, wp_0+$?s
everyPage, totalPage, Upe%rC(
currentPage, u_enqC3
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beginIndex); J zl6eo[;
} ,F|f. 7;
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privatestaticint getEveryPage(int everyPage){ }tz7b#
return everyPage == 0 ? 10 : everyPage; [WmM6UEVS
} ueudRb
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privatestaticint getCurrentPage(int currentPage){ $i&zex{\
return currentPage == 0 ? 1 : currentPage; uFE)17E
} C]6O!Pb0
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privatestaticint getBeginIndex(int everyPage, int Da|z"I
x
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currentPage){ @]j1:PN-
return(currentPage - 1) * everyPage; A"]YM'.
} Psf#c:*_)
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privatestaticint getTotalPage(int everyPage, int Y4-t7UlS;
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totalRecords){ eFgA 8kY)
int totalPage = 0; 7dWS
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if(totalRecords % everyPage == 0)
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totalPage = totalRecords / everyPage; _f83-':W6
else ^('wy};
totalPage = totalRecords / everyPage + 1 ; %EH)&k
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return totalPage;
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} LV Ge]lD
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privatestaticboolean hasPrePage(int currentPage){ tw;}jh
return currentPage == 1 ? false : true; 1Mzmg[L8
} 'L'R9&o<X
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privatestaticboolean hasNextPage(int currentPage, 7.Op<
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int totalPage){ X'srL j.
return currentPage == totalPage || totalPage == dV_G1'
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0 ? false : true; la!~\wpa
} :TbgFQ86~
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} o/E >f_k[
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ';CNGv -
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面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Ud?Q%)X
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做法如下: t Q)qCk07
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >:-$+I
j#|ZP-=1_
的信息,和一个结果集List: Z.,MVcd
java代码: oA
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VA%J\T|G2\
/*Created on 2005-6-13*/ I7onX,U+
package com.adt.bo; B,@i
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import java.util.List; m
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import org.flyware.util.page.Page; |yCMt:Hk
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/** e~OpofJNb
* @author Joa 2y4bwi
*/ *dQSw)R
publicclass Result { 5pX6t
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private Page page; /~1+i'7V.,
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private List content; dysS9a,
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/** [Xkx_B
* The default constructor &>O+}>lr9
*/ \bXa&Lq
public Result(){ =;L|gtH"
super(); 4W75T2q#
} 2?C)&
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/** F ,kZU$
* The constructor using fields 8*X4\3:*N
* &=[WIG+rk
* @param page Qs!5<)6
* @param content w0.
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*/ + {]j]OP
public Result(Page page, List content){ WJi]t9 3
this.page = page; ]Ljf?tk
this.content = content; %d@z39-;
} [),ige
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/** Ry&6p>-
* @return Returns the content. tbr=aY$jY
*/ gGYKEq{j(
publicList getContent(){ +`4A$#$+y
return content; T{"(\X$
} 4+n\k
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/** 9r9NxKuAO
* @return Returns the page. Z+SRXKQ
*/ /
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public Page getPage(){ y =@N|f!
return page; }V>T M{
} Om&Dw|xG8
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/** Ri'n
* @param content ]~-r}`]
* The content to set. @EAbF>>
*/ P>T"cv
public void setContent(List content){ NK+o1
this.content = content; KvSG;
} 4i bc
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/** 7)m9"InDI
* @param page 1C.VnzRnJ
* The page to set. :UdF
*/ }Z>)DN=+
publicvoid setPage(Page page){ `oJ [u:b
this.page = page; KoY F]
} pAEx#ck
} ~[: 2I
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2. 编写业务逻辑接口,并实现它(UserManager, ysN3
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UserManagerImpl) 9uY'E'm*
java代码: <3iMRe
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/*Created on 2005-7-15*/ a.'*G6~Qgw
package com.adt.service; ^.tg 7%dJ
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import net.sf.hibernate.HibernateException; qR.Q,(b|
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import org.flyware.util.page.Page; ^8tEach
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import com.adt.bo.Result; )"LJ
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/** )[ ,A_3E
* @author Joa .hiSw
*/ -di o5a
publicinterface UserManager { mmsPLv6
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public Result listUser(Page page)throws VL^EHb7
d _
e WcI
HibernateException; Q\)F;: |
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} *"kM{*3:v
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java代码: pp2~Meg
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/*Created on 2005-7-15*/ Qd6F H2Pl
package com.adt.service.impl; WHI`/FM
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import java.util.List; E9}C #
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import net.sf.hibernate.HibernateException; H"KCK6
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import org.flyware.util.page.Page; r>\bW)e
import org.flyware.util.page.PageUtil; }Lv;!
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import com.adt.bo.Result; eQ"E
import com.adt.dao.UserDAO; :4s1CC+@\
import com.adt.exception.ObjectNotFoundException; _U0f=m
import com.adt.service.UserManager; 1}37Q&2
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/**
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* @author Joa _6Ha
*/ 9kojLqCT
publicclass UserManagerImpl implements UserManager { 7KPwQ?SjT
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private UserDAO userDAO; V1?]|HTQcT
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/** ca}2TT&t
* @param userDAO The userDAO to set. -+5>|N#
*/ {t!!Uz 7
publicvoid setUserDAO(UserDAO userDAO){ Zov~B-Of:
this.userDAO = userDAO; .o8t+X'G
} &R siVBA
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/* (non-Javadoc) m4& /s
* @see com.adt.service.UserManager#listUser nie% eC&U
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(org.flyware.util.page.Page) I|J/F}@p
*/ Mlq.?-QgIL
public Result listUser(Page page)throws e%6QTg5#
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HibernateException, ObjectNotFoundException { i&k7-<
int totalRecords = userDAO.getUserCount(); vj*%Q(E6Pt
if(totalRecords == 0) P&q7|ST%N
throw new ObjectNotFoundException cFv8 Od
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("userNotExist"); rbQR,Nf2x
page = PageUtil.createPage(page, totalRecords); CNIsZv@Q
List users = userDAO.getUserByPage(page); RL<c>PY
returnnew Result(page, users); Ha ]YJ}
} 5?L<N:;J_
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} Q &t<Y^B
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >Se,;cB'/]
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询,接下来编写UserDAO的代码: /@Zrq#o
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3. UserDAO 和 UserDAOImpl: 8X0z~&
java代码: (ik\|y% A
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/*Created on 2005-7-15*/ `"~%bS
package com.adt.dao; QM]YJr3rE
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import java.util.List; T)})
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import org.flyware.util.page.Page; ipILG4
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import net.sf.hibernate.HibernateException; j7c3(*Pl
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/** pmilrZmm]
* @author Joa d[35d J7F
*/ ;$tSb ~K+
publicinterface UserDAO extends BaseDAO { |CzSU1ma
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publicList getUserByName(String name)throws '\GbmD^F
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HibernateException; Z)\@i=m
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publicint getUserCount()throws HibernateException; :@)>r9N
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publicList getUserByPage(Page page)throws [9 RR8
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HibernateException; 3Y~>qGQwh
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}
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java代码: PuO&wI]:
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/*Created on 2005-7-15*/ YF:L)0H'O
package com.adt.dao.impl; @vB!u[{
3 9|MX21k
import java.util.List; 4H-'Dr=G
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import org.flyware.util.page.Page; iyp=lLk
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import net.sf.hibernate.HibernateException; FE{FGMq
import net.sf.hibernate.Query; LDg?'y;2
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import com.adt.dao.UserDAO; T5:G$-qL(
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/** [h:T*(R?
* @author Joa ]d%8k}U
*/ +H
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public class UserDAOImpl extends BaseDAOHibernateImpl "}JZU!?
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implements UserDAO { |a%Tp3Q~
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/* (non-Javadoc) Z:7fV5b(
* @see com.adt.dao.UserDAO#getUserByName TuYCR>P[
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(java.lang.String) sse.*75U
*/ $a%MOKr
publicList getUserByName(String name)throws M|[o aanY'
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HibernateException { =kqt
String querySentence = "FROM user in class :Lug7bUVD
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com.adt.po.User WHERE user.name=:name"; Y)a^(!<H<
Query query = getSession().createQuery evJ.<{M
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(querySentence); Yir
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query.setParameter("name", name); 0{[,E.
return query.list(); C{bgkzr
} ,'iE;o{Tu
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/* (non-Javadoc) (2
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* @see com.adt.dao.UserDAO#getUserCount() .-X8J t
*/ :U(A;U1,
publicint getUserCount()throws HibernateException { ;]jNk'oa
int count = 0; K}U-w:{
String querySentence = "SELECT count(*) FROM WSY}d
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user in class com.adt.po.User";
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Query query = getSession().createQuery zZC9\V}R
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(querySentence); -FlzEZ
count = ((Integer)query.iterate().next ED&
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()).intValue(); kn"(A.R
return count; f0aKlhEC
} gOOPe5+ J
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/* (non-Javadoc) (NnH:J`
* @see com.adt.dao.UserDAO#getUserByPage 0k(a VkZ I
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(org.flyware.util.page.Page) 9]wN Bd
*/ m7>JJX3=<
publicList getUserByPage(Page page)throws [\b0Lem
")HFYqP>9
HibernateException { ~<OSYb
String querySentence = "FROM user in class L`EBfz\n
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com.adt.po.User"; {s{j~M
Query query = getSession().createQuery w(TJ*::T
QW~1%`
(querySentence); `%Al>u5
query.setFirstResult(page.getBeginIndex()) Q'mM3pq4r
.setMaxResults(page.getEveryPage()); +|>kCtZH%
return query.list(); nmi|\mof
} N<KS(@v
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} xLZG:^(I
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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 a,#j =
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userManager.listUser(page)即可得到一个Page对象和结果集对象
H =^`!
Sw^u3
的综合体,而传入的参数page对象则可以由前台传入,如果用 ~PahoRS
\qK&q
webwork,甚至可以直接在配置文件中指定。 nSAdCJ;4
wtV#l4
下面给出一个webwork调用示例: X<; f
java代码: Jl9k``r*
yU}qOgXx
8d-t|HkN
/*Created on 2005-6-17*/ df #$9-
package com.adt.action.user; :e%Pvk
1!T1Y,w
import java.util.List; =-lb)Z"d
{9aE5kR
import org.apache.commons.logging.Log; "djw>|,N<
import org.apache.commons.logging.LogFactory; tlp@?(u
import org.flyware.util.page.Page; 3az&