Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 f~LM-7!zf}
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 oA _,jsD4
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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 v/4Bt2J
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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 .mse.$TK.^
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分页支持类: vB :_|B
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java代码: K'`N(WiL
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package com.javaeye.common.util; 9Okb)K95
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import java.util.List; kO]],Vy`
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publicclass PaginationSupport { J&xH"U
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publicfinalstaticint PAGESIZE = 30; O>=D1no*
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privateint pageSize = PAGESIZE; mgB7l0)b
i#@3\&{J>
privateList items; $6ZO
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privateint totalCount; USKa6<:{W
8?lp:kM
privateint[] indexes = newint[0]; -NG`mfu
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privateint startIndex = 0; piRP2Lbm*
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public PaginationSupport(List items, int >-s\$8En'
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totalCount){ :E ISms
setPageSize(PAGESIZE); pq"3)+3:
setTotalCount(totalCount); cG|ihG5)
setItems(items); 7/"g}
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setStartIndex(0); .c[v /SB]
} PKoB~wLH
K<HF!YU#I2
public PaginationSupport(List items, int >Lh+(M;+F
NR8YVO)5$
totalCount, int startIndex){ [@U2a$k+d
setPageSize(PAGESIZE); /( /)nYAjk
setTotalCount(totalCount); hw?'aXK{
setItems(items); VO|2
setStartIndex(startIndex); QU/Q5k
} |2 2~.9S
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public PaginationSupport(List items, int w<?v78sT
[p%@ pV
totalCount, int pageSize, int startIndex){ CU3[{a
setPageSize(pageSize); FFH9$>A
setTotalCount(totalCount); 4{Vw30DZ
setItems(items); nRpZ;X)'.
setStartIndex(startIndex); lW! U:
} \de824
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publicList getItems(){ o#X|4bES
return items; (>THN*i
} @\,WJmW
@D!KFJ
publicvoid setItems(List items){ |k~\E|^
this.items = items; VXforI
} y6|&bJ @
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publicint getPageSize(){ AP=mj
return pageSize; =;.#Bds
} @ \ip?=
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publicvoid setPageSize(int pageSize){ D*d@<&Bl4<
this.pageSize = pageSize; r40#-A$
} k'uN2m
A~ugx~S0
publicint getTotalCount(){ HH[b1z2D
return totalCount; |t^7L )&y
} 7<V(lX.{
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publicvoid setTotalCount(int totalCount){ FyN@mX
if(totalCount > 0){ s8T}ah!
this.totalCount = totalCount; Ug=8:a(U.
int count = totalCount / eiB5 8b3
EB'(%dH
pageSize; 3 }Z[d
if(totalCount % pageSize > 0) a%>p"4WL
count++; M$L1!o1Xf
indexes = newint[count]; ~ g$Pb[V
for(int i = 0; i < count; i++){ {uEu
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indexes = pageSize * mBgMu@zt)
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i; K1O0/2O
} dxlaoyv:
}else{ [nBlHI;&
this.totalCount = 0; cCN[c)[c|
} z5Hz-.
} jj8AV lN
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publicint[] getIndexes(){ IpQ51
return indexes; Jq) !)={
} )`]w\s
#
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publicvoid setIndexes(int[] indexes){ I3o6ym-i
this.indexes = indexes; Oa=0d;_
} O G#By6O
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publicint getStartIndex(){ +.MHI
return startIndex; ?}y?e}y*xZ
} {zhN>n_
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publicvoid setStartIndex(int startIndex){ I0oM\~#
if(totalCount <= 0) u(\O
this.startIndex = 0; ;Ad$Q9)EE
elseif(startIndex >= totalCount) bWAhK@epI
this.startIndex = indexes 'Uqz ,
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[indexes.length - 1]; 3=V79&
elseif(startIndex < 0) h_L-M}{OG
this.startIndex = 0; DOiL3i"H
else{ ?cf9q@eAH
this.startIndex = indexes ^yiRrcOo
1t/#ZT!X/
[startIndex / pageSize]; zuR!,-W
} k_.%(ZE
} 9r!psRA:`)
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publicint getNextIndex(){ iqURlI);P
int nextIndex = getStartIndex() + hkeOe
h\afO
pageSize; 2ku\R7
if(nextIndex >= totalCount) g|8G!7O
return getStartIndex(); `qp[x%7^
else p7}xgUxX
return nextIndex; !},_,J~(|
} !lp*0h(7
8W
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publicint getPreviousIndex(){ (gZKR2hO
int previousIndex = getStartIndex() - w N9I )hB
yZ=wT,Y
pageSize; IGEs1
if(previousIndex < 0) >
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return0; W>+\A"
else =m6;]16D
return previousIndex; tWy0%
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} < I[ Vv'x
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} 'Y{fah
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抽象业务类 F[mL_JU
java代码: .XQ_,
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/** daS l.:1
* Created on 2005-7-12 dq[X:3i
*/ X}C}
package com.javaeye.common.business; <hazrKUn
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import java.io.Serializable; swEE >=
import java.util.List; }cuU5WQ?%
kX!TOlk3
import org.hibernate.Criteria; eCHT)35u
import org.hibernate.HibernateException; #wn`choT'
import org.hibernate.Session; V*HkFT
import org.hibernate.criterion.DetachedCriteria; i|A0G%m] $
import org.hibernate.criterion.Projections; V4kt&61
import I[u%kir
;^VLx)q
org.springframework.orm.hibernate3.HibernateCallback; H]2cw{2
import I\eM8`Y$
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org.springframework.orm.hibernate3.support.HibernateDaoS M{:}.H<a
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upport; ^]_[dqd
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import com.javaeye.common.util.PaginationSupport; #qqIOjS^w
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public abstract class AbstractManager extends k$j4~C'$
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HibernateDaoSupport { H4l*
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privateboolean cacheQueries = false; i> }P V
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privateString queryCacheRegion; -DWyKR= j"
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publicvoid setCacheQueries(boolean w"?H4
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cacheQueries){ h0i/ v
this.cacheQueries = cacheQueries; R'M=`33M
} i|5.DhK}
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publicvoid setQueryCacheRegion(String 4KH8dau.fF
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queryCacheRegion){ 9eG{"0)
this.queryCacheRegion = #m
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queryCacheRegion; |%p;4b
} fjD/<`}v
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publicvoid save(finalObject entity){ D}.Pk>5
getHibernateTemplate().save(entity); V 5ve
} k&TZ
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publicvoid persist(finalObject entity){ ~8fy
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getHibernateTemplate().save(entity); k
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} z`)i"O]-K_
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publicvoid update(finalObject entity){ {Y0Uln5u
getHibernateTemplate().update(entity); yiourR)H<
} D7v-+jypp
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publicvoid delete(finalObject entity){ QkY]z~P4
getHibernateTemplate().delete(entity); "#<P--E 9
} c4\Nuy
} vx+/J
publicObject load(finalClass entity, kMJf!%L (
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finalSerializable id){ WR5@S&fU`
return getHibernateTemplate().load |{STkV]
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(entity, id); Ah_,5Z@&R
} D]P_tJI
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publicObject get(finalClass entity, QGC%, F"+
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finalSerializable id){ W##~gqZ/
return getHibernateTemplate().get Es7+bFvsE8
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(entity, id); Xc>M_%+R
} L
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publicList findAll(finalClass entity){ @N(*1,s2
return getHibernateTemplate().find("from Z?@oe-mz
@Yu=65h
" + entity.getName()); <SPT2NyX
} (4GDh%
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publicList findByNamedQuery(finalString h<1pGQV
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namedQuery){ [yyL2=7
return getHibernateTemplate `!um)4
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().findByNamedQuery(namedQuery); ^!FLi7X
} bJWPr
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publicList findByNamedQuery(finalString query, SJ%h.u@&@F
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finalObject parameter){ F<YXkG4pO
return getHibernateTemplate LBw$K0
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().findByNamedQuery(query, parameter); @OB7TI_/
} }G3:QD
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publicList findByNamedQuery(finalString query, 23iMG]J&
lx H3a :gm
finalObject[] parameters){ ^sP-6 ^
return getHibernateTemplate @5,Xr`]
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().findByNamedQuery(query, parameters); "C~Zl&3
} LJ{P93aq`^
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publicList find(finalString query){ cvk$ I"q+
return getHibernateTemplate().find 4UISuYg'
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(query); i2yE-sgF
} AEw~LF2w
;) (F4
publicList find(finalString query, finalObject I%b}qC"5M
~2L]K4Z^
parameter){ h3YWqSj
return getHibernateTemplate().find huTWoMU
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(query, parameter); 5f-eWW]!
} Ty5}5)CRZ
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public PaginationSupport findPageByCriteria z:JQ3D7/we
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(final DetachedCriteria detachedCriteria){ T:|PSJc0
return findPageByCriteria g?1! /+
#k/NS
(detachedCriteria, PaginationSupport.PAGESIZE, 0); L
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} i!7|YAu
7|Bg--G1
public PaginationSupport findPageByCriteria 2)4oe
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(final DetachedCriteria detachedCriteria, finalint %kXg|9Bx!
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startIndex){ v$]eCj'
return findPageByCriteria S
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(detachedCriteria, PaginationSupport.PAGESIZE, ^E}};CsT
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startIndex); 1
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} qf?X:9Wt
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public PaginationSupport findPageByCriteria ) |Md"r_B
j3_vh<U\
(final DetachedCriteria detachedCriteria, finalint /5&'U!:+
VqBb=1r%o7
pageSize,
#Ks2a):8
finalint startIndex){ |9x H9@^f
return(PaginationSupport) ;'7gg]
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getHibernateTemplate().execute(new HibernateCallback(){ %DIZgPd\
publicObject doInHibernate uh
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(Session session)throws HibernateException { (N/KP+J$n
Criteria criteria = T$vDw|KSVP
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detachedCriteria.getExecutableCriteria(session); /j(3 ~%]o4
int totalCount = t/Y)% N
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((Integer) criteria.setProjection(Projections.rowCount ;($" _h
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()).uniqueResult()).intValue(); hY[Vs5v
criteria.setProjection Unc_e
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(null); e0cVg
List items = ]s<}'&
EN/e`S$)
criteria.setFirstResult(startIndex).setMaxResults #24eogo~
Yj#4{2A
(pageSize).list(); 2/4,iu(T`c
PaginationSupport ps = "79"SSfOc
^!yJ;'H\
new PaginationSupport(items, totalCount, pageSize, 8-uRn38
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startIndex); d^W1;0
return ps; =*Ru2
} 9}*<8%PSt,
}, true); Z`{ZV5
} wr{ [4$O
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public List findAllByCriteria(final d@IV@'Q7u
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DetachedCriteria detachedCriteria){ W &HF*Aw
return(List) getHibernateTemplate jt,dr3|/n
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().execute(new HibernateCallback(){ ne-;gTP;
publicObject doInHibernate 7,:$, bL
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(Session session)throws HibernateException { ]UFbG40Zo
Criteria criteria = h.WvPZ2U
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detachedCriteria.getExecutableCriteria(session); Pt^SlX^MM
return criteria.list(); 3qNLosm#M
} K]s*rPT/,
}, true); }V I}O{
} KCc7u8
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public int getCountByCriteria(final 6l,oL'$}P1
9#iv|X
DetachedCriteria detachedCriteria){ B?pNF+?'z
Integer count = (Integer) >jH%n(TcC
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getHibernateTemplate().execute(new HibernateCallback(){ 5kbbeO|0G
publicObject doInHibernate 'j27.Ry.
L^><APlX
(Session session)throws HibernateException { _&xi})E^O]
Criteria criteria = 6X`i*T$.
).D+/D/"2
detachedCriteria.getExecutableCriteria(session); A$Tp0v`t
return (eEs0
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criteria.setProjection(Projections.rowCount "Di8MMGOY
q47:kB{d
()).uniqueResult(); f:hsE
} fd1z
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}, true); _^w^tfH]
return count.intValue(); 7(zY:9|(
} )-LSn
} cvnRd.&
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用户在web层构造查询条件detachedCriteria,和可选的 4--[.j*W
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ^/Frg<>'p
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PaginationSupport的实例ps。 #mc GT\tQ
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ps.getItems()得到已分页好的结果集 Gn?<~8a
ps.getIndexes()得到分页索引的数组 B#x.4~YX
ps.getTotalCount()得到总结果数 }tH6E
ps.getStartIndex()当前分页索引 C%kIxa)
ps.getNextIndex()下一页索引 UxVxnJ_
ps.getPreviousIndex()上一页索引 5]@"f/
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.
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 HFrwf{J
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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 qCgoB 0
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一下代码重构了。 Oi4tG&q
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我把原本我的做法也提供出来供大家讨论吧: $|bdeQPr\
)Fh5*UC
首先,为了实现分页查询,我封装了一个Page类: H)l7:a
java代码: ;B!u=_'
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/*Created on 2005-4-14*/ [}t^+^/
package org.flyware.util.page; u~q6?*5
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/** Ov PTgiI!N
* @author Joa &x<y4ORH|
* ._IBO; *@
*/ Sn!5/9Y
publicclass Page { R\d)kcy4
IG=# 2 /$
/** imply if the page has previous page */ $c<NEt_\
privateboolean hasPrePage; A
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/** imply if the page has next page */ hO] vy>i;
privateboolean hasNextPage; M"Q{lR
u</LgOP`-
/** the number of every page */ NANgV~Y&
privateint everyPage; T.?}iz=ZEq
's_[#a;Vp
/** the total page number */ p]erk
privateint totalPage; dcbE<W#ss
@pkQ2OM
2
/** the number of current page */ f*46,`x
privateint currentPage; SM8Wg>
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/** the begin index of the records by the current 4(D/~OG-6
#4BwYj(Sl
query */ xfK@tLEZ-1
privateint beginIndex; j9^V)\6)
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K|sk]2.
/** The default constructor */ @Z2^smf
public Page(){ zW9/[Db
9mRP%c#(
} '4"c#kCKL
$@^*lUw
/** construct the page by everyPage <kOdd)X
* @param everyPage *r(Qy0(
* */ ve f9*u`
public Page(int everyPage){ u%sfHGrH
this.everyPage = everyPage;
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} #G!\MYfQt
8 @A}.:
/** The whole constructor */ 9zE/SDu7\
public Page(boolean hasPrePage, boolean hasNextPage, / ?Hq
9oQ$w?=#$
g$h`.Fk,
int everyPage, int totalPage, ZgA+$}U)uW
int currentPage, int beginIndex){ tE WolO[\
this.hasPrePage = hasPrePage; }?^]-`b
this.hasNextPage = hasNextPage; ]8f$&gw&A
this.everyPage = everyPage; D=@bP B>
this.totalPage = totalPage; Z;~ 7L*|
this.currentPage = currentPage; V
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this.beginIndex = beginIndex; o@sL/5,
} )|wC 1J!L
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/** d.$0X/0
* @return suHisc*
* Returns the beginIndex. [*U.bRs
*/ yb6gYN
publicint getBeginIndex(){ P&IS$FC.\
return beginIndex; ~s*kuj'%+
} moRo>bvN~
GBY{O2!3u
/** w8cbhc
* @param beginIndex |[!7^tU*
* The beginIndex to set. V3(8?Fz.
*/ Ug )eyu
publicvoid setBeginIndex(int beginIndex){ !v.
<H]s)
this.beginIndex = beginIndex; lYT_Y.%I
} MY'T%_id
B ?l0u
/** 9Ed=`c
* @return tMH2
* Returns the currentPage. M|fC2[]v B
*/ B`)TRt+'.
publicint getCurrentPage(){ |3 mcL'
return currentPage; VS3lz?o?6g
} %7[q%S
:. u2^*<
/** G=er0(7<
* @param currentPage RFPcH8-u7
* The currentPage to set. c#-*]6x
*/
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publicvoid setCurrentPage(int currentPage){ _Kbj?j
this.currentPage = currentPage; Ca-.&$f
} 7(d#zu6n
*dN_=32u
/** KM?w{ ~9
* @return -S#jOr
* Returns the everyPage. <99/7>#
*/ YJ|U|[
publicint getEveryPage(){ 8jY<S+[o
return everyPage; _nM 7SK
} iJ`zWpj+{Q
CB#B!;I8v
/** Xk!wT2;
* @param everyPage B(f_~ ]
* The everyPage to set. Xl:.`{5L
*/ a(kY,<}
publicvoid setEveryPage(int everyPage){ v
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this.everyPage = everyPage; 5O;D\M{>
} l#~pK6@W
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/** V|~o`(]
* @return U>sEFzBup
* Returns the hasNextPage. eD8e0
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*/ gVrfZ&XF84
publicboolean getHasNextPage(){ !hjF"Pa
return hasNextPage; tSe[*V4{'
}
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/** `{m,&[n
* @param hasNextPage %j/pln&
* The hasNextPage to set. KcUR
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*/ X]o"4#CQIX
publicvoid setHasNextPage(boolean hasNextPage){ B#?rW*yEe
this.hasNextPage = hasNextPage; 'S|7<<>4k
} +,cd$,18
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/** zI\+]U'
* @return U9K'O !i>
* Returns the hasPrePage. t1NGs-S3
*/ j#xGB]
publicboolean getHasPrePage(){ "dT"6,
return hasPrePage; 10)RLh|+
} {T-^xwc
1 e]D=2y
/** Z;,G:@,
* @param hasPrePage 0
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* The hasPrePage to set. nSRNd
A
*/ |o+*Iy)
publicvoid setHasPrePage(boolean hasPrePage){ b
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this.hasPrePage = hasPrePage; [H{@<*
} @vB-.XU
jz]}%O
/**
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* @return Returns the totalPage. MiR$N
* ~FQHT?DAo
*/ #d06wYz=
publicint getTotalPage(){ /='Q-`?9
return totalPage; u:Ye`]~o
} BMqr YW
CRD=7\0(D+
/** Ql%B=vgKL
* @param totalPage UNK.39
* The totalPage to set. Nukyvse
*/ V]GF53D
publicvoid setTotalPage(int totalPage){ ^tjw }sE
this.totalPage = totalPage; SUv'cld
} P]TT8Jgw
{9X mFa
} vCNq2l^CW
#6v357-5
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bt(Y@3;
)EQz9
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 v~yw-}fk%
H^54o$5
个PageUtil,负责对Page对象进行构造: KVh#"]<WV
java代码: 1)jeawVmj
`SOQPAnK+;
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/*Created on 2005-4-14*/ \yZVn6GVr
package org.flyware.util.page; i7Cuc+j8
3%Eu$|B
import org.apache.commons.logging.Log; :U *8S\$
import org.apache.commons.logging.LogFactory; 5Zd oem
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/** a+\<2NXYD
* @author Joa 5ba e-
* >MSK.SNh
*/ >*opE I+
publicclass PageUtil { oK
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privatestaticfinal Log logger = LogFactory.getLog ;obOr~Jx'5
d7mn(= &
(PageUtil.class); }2;iIw`
<:NahxIlu
/** :WX
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* Use the origin page to create a new page u|T]Ne
* @param page /zb/am1#
* @param totalRecords (z.n9lkfi
* @return ZNM9@;7
*/ |TP,
publicstatic Page createPage(Page page, int 8|<</v8i
=[&+R9s
totalRecords){ 6)*B%$?x
return createPage(page.getEveryPage(), 1G.?Y3DC<
Z^z{,
u;!
page.getCurrentPage(), totalRecords); 2~l7WW+lx,
} F_9
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/** MmfBFt*
* the basic page utils not including exception +3o0GJ
< \fA}b
handler ?|/K(}
* @param everyPage x;$ESPPg
* @param currentPage M:/(~X{?
* @param totalRecords /e[m;+9^&
* @return page zi3v,Kq
*/ iETUBZ
publicstatic Page createPage(int everyPage, int ~[dL:=?c
}A,!|m4
currentPage, int totalRecords){ KvEv0L<ky
everyPage = getEveryPage(everyPage); `GW&*[.7
currentPage = getCurrentPage(currentPage); |59)6/i
int beginIndex = getBeginIndex(everyPage, |JF,n~n
*4NY"EwjN
currentPage); gzn:]Y^
int totalPage = getTotalPage(everyPage, n|6G\99l+M
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totalRecords); 8h }a:/
boolean hasNextPage = hasNextPage(currentPage, *~shvtq
U# S-x5Gn
totalPage); 2oV6#!{Z
boolean hasPrePage = hasPrePage(currentPage); F6111Q </
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returnnew Page(hasPrePage, hasNextPage, LAo$AiTUR{
everyPage, totalPage, li
v=q
currentPage, CHZ/@gc
<5}I6R;
beginIndex); ygj%VG
} U~)5 {
7M7Lj0Y)L
privatestaticint getEveryPage(int everyPage){ 8/(}Wet
return everyPage == 0 ? 10 : everyPage; >l><d!hw
} wdfbl_`T
2uN3:_w
privatestaticint getCurrentPage(int currentPage){ ^|p D(v
return currentPage == 0 ? 1 : currentPage; LH)1IGAx2y
} i!*<LIq
G+Z ,ic
privatestaticint getBeginIndex(int everyPage, int ,Yx<"2 W
#b;k+<n[X
currentPage){ mRRZ/m?A(
return(currentPage - 1) * everyPage; E;{CoL
} |h6!b t!=
gaz",kK<
privatestaticint getTotalPage(int everyPage, int hnB`+!
xvl{o
totalRecords){ #n{4f1TZ
int totalPage = 0; @s
cn ?t
" "m-5PGYo
if(totalRecords % everyPage == 0) 9
@ <
totalPage = totalRecords / everyPage; d^nO&it
else t0e5L{ QJ
totalPage = totalRecords / everyPage + 1 ; -dO8Uis$
q4w]9b/
return totalPage; p+|8(w9A${
} Z!~_#_Ugl
{6 h 1
privatestaticboolean hasPrePage(int currentPage){ ^h2+""
return currentPage == 1 ? false : true; 3^%2,
} ?%$O7_ThvA
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privatestaticboolean hasNextPage(int currentPage, ;22?-F^
3IQI={:k|D
int totalPage){ +DXP&Q
return currentPage == totalPage || totalPage == fX 1%I
KYw7Jx`l
0 ? false : true; 4-SU\_
} Pg:xC9w4
&z40l['4bz
4gC(zJ
} @O'NJh{D`
}Vob)r{R@
dWiNe!oY2
P ?f${t+
@(35I
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 r>ed/<_>m;
mY/"rm
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Q"~%T@e
oF>`>
做法如下: Z81;Y=(
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 9/e>%1.
c`\/]
的信息,和一个结果集List: ]tT=jN&(
java代码: y[85eM
qQ^CSn98J
B-w`mcqp$
/*Created on 2005-6-13*/ Vdxo
package com.adt.bo; `r-Jy{!y4
vJGH8$%;,
import java.util.List;
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g$#A'Du
import org.flyware.util.page.Page; Qx,#Hj
G4:\6fu
/** z"yW):X
* @author Joa mOh?cjOi
*/ aWJ
BYw6{L
publicclass Result { PkyX,mr#1
i&lW&]
private Page page; B-]bhA4|:
!9NF@e'&!
private List content; A32Sdr'D
?2da6v,t
/** f!yl&ulKU
* The default constructor 5j.@)XXe
*/ WHBGhU
public Result(){ X9|*`h <
super(); Uv>e :U7 ;
} %i3[x.M
%.f%Q?P
/** |wv+g0]Pg^
* The constructor using fields ,~38IIS>_
* +`gU{e,p
* @param page /{hT3ncb
* @param content [<U=)!Swg
*/ Ewr2popK
public Result(Page page, List content){ kI!@J6
this.page = page; ~ !mY0odH
this.content = content; F*#!hWtb
} mMXDzAllB
_;5zA"~c#@
/** q?mpvpLG
* @return Returns the content. @]#[TbNo
*/ O>hh
publicList getContent(){ goyDG/
return content; *&Iv Eu
} BNjMq
H/M]YUs/3
/** 1+-Go}I
* @return Returns the page. ktynIN
*/ h>*3i#
public Page getPage(){ Hs8JJGXWB
return page; F7jkl4
} 3]9wfT%d
>f Hu
/** HxW/t7Z(
* @param content 8$]SvfX
* The content to set. G$'UK
*/ eP:\\;
;
public void setContent(List content){ 6p&2A
this.content = content; `u_MdB}<x;
} zQ,M795@EA
vv2[t
/** E A55!
* @param page P(I%9
* The page to set. ji4bz#/B0
*/ DAf@-~c
publicvoid setPage(Page page){ gV9bt~
this.page = page; 'j{o!T0
} N.Q}.(N0
} ^fO9oPM|
Oh10X.)i
XPdqE`w=$p
f$5pp=s: n
2#yDVN$
2. 编写业务逻辑接口,并实现它(UserManager, wBw(T1VN
V>obMr^5
UserManagerImpl) ?-2s}IJO
java代码: \v=@'
`S4*~Xx
j-"34
/*Created on 2005-7-15*/ ^yl}/OD
package com.adt.service; 60ciI,_`
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import net.sf.hibernate.HibernateException; >iG3!Td)y
:|ahu
import org.flyware.util.page.Page; 3Ur_?PM+C
*]R5bj.!o
import com.adt.bo.Result; 4bw4!z9G
`bV&n!Y_
/** stW
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* @author Joa {fV$\^c
*/ ,H.5TQ#
publicinterface UserManager { h0dZr-c
Nr*X1lJ6
public Result listUser(Page page)throws d)Z&_v<|
umnQ$y
0
HibernateException; kMLJa=]$
tEo-Mj5:
} NMhpKno
rx9y^E5T`;
?>V>6cDQ
YjL'GmL<
v?,@e5GZ
java代码: I][&*V1
!J@!2S9
5#X R1#`
/*Created on 2005-7-15*/ q7soV(P
package com.adt.service.impl; .$y'>O*$G
BAvz @H
import java.util.List; o6~JAvw
~9#x=nU:+V
import net.sf.hibernate.HibernateException; ;P;c!}:\b
:qB|~"9O
import org.flyware.util.page.Page; R6;#+ 1D
import org.flyware.util.page.PageUtil; Z.Dg=>G]
#XqCz>Z
import com.adt.bo.Result; UA~ 4O Q]
import com.adt.dao.UserDAO; aMHC+R1X
import com.adt.exception.ObjectNotFoundException; w8 UUeF
import com.adt.service.UserManager; xb0,dZb
LCj3{>{/=
/** 'PFjZGaKR
* @author Joa ae@!M
*/ |=,jom
publicclass UserManagerImpl implements UserManager { p"jze3mF
I
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private UserDAO userDAO; u=]*,,5<
C$C>RYE?.
/** 7 j=KiiI
* @param userDAO The userDAO to set. 9c,/490Q
*/ #l:
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publicvoid setUserDAO(UserDAO userDAO){ BV7P_!vt
this.userDAO = userDAO; Ac|dmu
} puWMgvv
(>x05nh
/* (non-Javadoc) mDbTOtD
* @see com.adt.service.UserManager#listUser Z^4+ 88
M,li\)J!&
(org.flyware.util.page.Page) aTeW#:m
*/ $Q'z9ghEg
public Result listUser(Page page)throws +0Q +0:
<BZC5b6
HibernateException, ObjectNotFoundException { $^?VyHXvY
int totalRecords = userDAO.getUserCount(); xJ. kd
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if(totalRecords == 0) g:y4C6b
throw new ObjectNotFoundException ~UO}PI`C
* O?Yp%5NH
("userNotExist"); ]plp.f#av
page = PageUtil.createPage(page, totalRecords); [v*q%Mi_
List users = userDAO.getUserByPage(page); x
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returnnew Result(page, users); M
| "'`zc
} \**j\m
?fq!BV
} ' F9gp!s8~
p0zC(v0*
l,l6j";ohd
vS0 ii
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 S1y6G/e9
J+
S]Qoz
询,接下来编写UserDAO的代码: u)o-H!a
3. UserDAO 和 UserDAOImpl: ,~ZD"'*n6g
java代码: GCO: !,1
?H@<8Ra=3
$^{#hYq)o
/*Created on 2005-7-15*/ L2EQ 9i'[
package com.adt.dao; @d 7V@F0d
Fih
pp<
import java.util.List; +M_ _\7
L{8_6s(:
import org.flyware.util.page.Page; Rky]F+J
_]4p51r0
import net.sf.hibernate.HibernateException; a%b E}
jED.0,+K!
/** =|IlORf<
* @author Joa g([:"y?
*/ ]2)A/fOW
publicinterface UserDAO extends BaseDAO { zEW+1-=)+7
|%XTy7^a
publicList getUserByName(String name)throws SKnYeT
jLVD37 P^
HibernateException; *OFG3 uM
B^P&+,\[}
publicint getUserCount()throws HibernateException;
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eU%49 A
publicList getUserByPage(Page page)throws o&%v"#H2
D0 p*Sg
HibernateException; wv{ Qx^
C2v_],]
} !.mR]El{K
4l%W]'
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o68i0aFW
T
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java代码: DWKQ>X6
*1`X}
b1 w@toc
/*Created on 2005-7-15*/ 1s=Q~*f~d
package com.adt.dao.impl; G)}[!'<rR
jD9u(qAlH
import java.util.List; Y&O2;q/B
&U]/SFY
import org.flyware.util.page.Page; <O'U-.
Gc
>rEZ$h
import net.sf.hibernate.HibernateException; naf ~#==vc
import net.sf.hibernate.Query; ySO\9#Ho
9c)#j&2?H
import com.adt.dao.UserDAO; ;n(f?RO3X
Fk 3(( n=
/** P%e7c,
* @author Joa = N*Jis
*/ *
CR#D}F
public class UserDAOImpl extends BaseDAOHibernateImpl N?vb^?
5<ruN11G
implements UserDAO { k B]`py!
L7 }nmP>aR
/* (non-Javadoc) ; o_0~l=-/
* @see com.adt.dao.UserDAO#getUserByName Dbn344s
g[pU5%|"[
(java.lang.String) -\?-
*/ xWzybuLp
publicList getUserByName(String name)throws m-
<y|3
a&b/C*R_
HibernateException { NLL"~
String querySentence = "FROM user in class Ju47} t%HB
VM\R-[
com.adt.po.User WHERE user.name=:name"; ~bb6NP;'L
Query query = getSession().createQuery P5_Ajb(@'
{ %X2K
(querySentence); lF!PiL
query.setParameter("name", name); vNs%e/~vj
return query.list(); <<MpeMi
} gp`@dn';
cHF W"g78
/* (non-Javadoc) )>FAtE
* @see com.adt.dao.UserDAO#getUserCount() "PI;/(kR
*/ o( zez
publicint getUserCount()throws HibernateException { *FC8=U2\X
int count = 0; C
6
\
String querySentence = "SELECT count(*) FROM C][hH?.
L4/ns@e
user in class com.adt.po.User"; n~yKq"^
Query query = getSession().createQuery St%x\[D
+-|""`I1I
(querySentence); ^ul1{
count = ((Integer)query.iterate().next 0@"'SKq
'xqyG XI
()).intValue(); ?Cf'IBpN
return count; E72N=7v"
} tz;o6,eb
F7JO/U^oU
/* (non-Javadoc) 6L8nw+mEK
* @see com.adt.dao.UserDAO#getUserByPage %MHL@Nn>e
BNdq=|,+"
(org.flyware.util.page.Page) jJiuq#;T3
*/ X.4WVI
publicList getUserByPage(Page page)throws U%:%. Bys
[l5jPL}6
HibernateException { ~q566k!Ll!
String querySentence = "FROM user in class 9/0H,qZc
*>=tmW;%
com.adt.po.User"; }}TPu8Rl
Query query = getSession().createQuery /8qR7Z^HZ
Wu$ryX
(querySentence); Z .gb'
query.setFirstResult(page.getBeginIndex()) EWDsBNZaI
.setMaxResults(page.getEveryPage()); PM[W7gT
return query.list(); j? BL8E'
} Q*#Lr4cm{
ON\bD?(VY
} $EFS_*<X
i;%G Z8
!I?C8)
2: gh q
-"nkC
至此,一个完整的分页程序完成。前台的只需要调用 IwnDG;+Ap
S,:!H@~B
userManager.listUser(page)即可得到一个Page对象和结果集对象 1w7tRw
}kmAUaa,Z
的综合体,而传入的参数page对象则可以由前台传入,如果用 cF15Mm2
I*a@_EO
webwork,甚至可以直接在配置文件中指定。 #(614-r/
?fy37m(M}
下面给出一个webwork调用示例: /Kli C\
java代码: OoA!N-Q
t!rrYBSCr
-rcEG!
/*Created on 2005-6-17*/ E6~VHQa2?
package com.adt.action.user; }~@/r5Zl
Lf%3-P
import java.util.List; n^[a}DX0
V"4L=[le
import org.apache.commons.logging.Log; }V]b4t
import org.apache.commons.logging.LogFactory; rwj+N%N
import org.flyware.util.page.Page; >WLX5i&
NHyUHFY
import com.adt.bo.Result; }cMkh
import com.adt.service.UserService; h<&GdK2U+
import com.opensymphony.xwork.Action; 4Px|:7~wT8
a+LK~mC*
/** ,HDhP
* @author Joa ASy?^Jrs5
*/ 7(o`>7x*
publicclass ListUser implementsAction{ D@uVb4uK
moxmQ>xoH
privatestaticfinal Log logger = LogFactory.getLog %l&oRBC
JR`$t~0t
(ListUser.class); Q9OCf"n $
B`eK_'7t
private UserService userService; UeFJ5n'x:
&l2xh~L
private Page page; ?X|q
{ax]t-ZwJ5
privateList users; r*b+kSh
9RlJf=Z#H
/* afX|R
* (non-Javadoc) ((]i}s0S
* [(*Eg!?W=
* @see com.opensymphony.xwork.Action#execute() b(N\R_IQ~
*/ Wx-0Ip'9
publicString execute()throwsException{ !~C%0{9+u@
Result result = userService.listUser(page); Nxt:U{`T'
page = result.getPage(); _}p[(sTV
users = result.getContent(); >+7{PF+sB
return SUCCESS; ]
hK}ASC
} %7mGMa/
n32"cFPpT
/** _s@PL59,
* @return Returns the page. '-A;B.GV%
*/ 5XX)8gAo
public Page getPage(){ P0>2}/;o
return page; +:^l|6%}
} -'qVnu
J(}PvkA
/** 15J"iN2"W
* @return Returns the users. &