Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 nWg)zj:
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 IOsDVIXL\
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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 fae yk]u
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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 dQoMAsxzM
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分页支持类: ]t0S_UH$
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java代码: MPw7!G(qj
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package com.javaeye.common.util; +m},c-,=$w
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import java.util.List; [~0q )
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publicclass PaginationSupport { Qi L
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publicfinalstaticint PAGESIZE = 30; F#R\Ot,hv
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privateint pageSize = PAGESIZE; _ o3}Ly}
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privateList items; ZOsn,nF
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privateint totalCount; Q2PwO;E.`C
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privateint[] indexes = newint[0]; [Y~ s
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privateint startIndex = 0; CplRnKra
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public PaginationSupport(List items, int _ h-X-s Y
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totalCount){ jg/<"/E
setPageSize(PAGESIZE); 00TdX|V`
setTotalCount(totalCount); `v
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setItems(items); 8hA=$}y&x
setStartIndex(0); h}_q
} w\4m-Z{
f ebh1rUX
public PaginationSupport(List items, int |Q;1;QXd
pP&M]'
totalCount, int startIndex){ TD9`SSpP
setPageSize(PAGESIZE); z#/*LP#oY
setTotalCount(totalCount); U0T N8O}Z
setItems(items); u{z{3fW_
setStartIndex(startIndex); %q^]./3p
} EC/R|\d?Un
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public PaginationSupport(List items, int DVH><3FF
}5Uf`pM8
totalCount, int pageSize, int startIndex){ mAa]Et.
setPageSize(pageSize); EUqG"h5#A{
setTotalCount(totalCount); bS<p dOX_
setItems(items); S\(_"xJPp
setStartIndex(startIndex); Mr(3]EfgO
} sxtGl^,mU:
4r&~=up]
publicList getItems(){ 4N&}hOM'S
return items; >d\I*"C+d
} !NjE5USi
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publicvoid setItems(List items){ NBX/V^
this.items = items; 8),Y|4
} %b9M\
Z%R^;8 !~
publicint getPageSize(){ iqeGy&F-
return pageSize; I5]zOKlVR
} \mloR
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publicvoid setPageSize(int pageSize){ [qB=OxH?
this.pageSize = pageSize; tP-c>|cz
} Wt=[R 4=
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publicint getTotalCount(){ |1o]d$3m
return totalCount; 0'uj*Y{L
} m`~ Qr~
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publicvoid setTotalCount(int totalCount){ 75y#^pD?c
if(totalCount > 0){ Yi`.zm
this.totalCount = totalCount; RiklwR#~r/
int count = totalCount / ff0,K#-
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pageSize; uY,FugWbl
if(totalCount % pageSize > 0) 0dW1I|jR
count++; xlAaIo)T
indexes = newint[count]; e]QkZg2?Yn
for(int i = 0; i < count; i++){ DVd/OU
indexes = pageSize * ?jbam!A
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i; j*"s~8u4
} CJ_B.
}else{ c1i7Rc{q
this.totalCount = 0; 2r,fF<WQ
} IWkBq]Y
} dU,/!|.K
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publicint[] getIndexes(){ A.[T#ZB.4
return indexes; LBg#KQ@
} V4 7Fp
I ;_.tG
publicvoid setIndexes(int[] indexes){ 1na[=Q2
this.indexes = indexes; -?uwlpm#
} J [1GP_
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publicint getStartIndex(){ k(MQ:9'|
return startIndex; *M{1RMc
} ~'ovJ46tx
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publicvoid setStartIndex(int startIndex){ f*Kipgp
if(totalCount <= 0) |^ qW
this.startIndex = 0; #\}hN~@F
elseif(startIndex >= totalCount) E$cr3 t7Xy
this.startIndex = indexes &5B+8>
?F-,4Ox{/
[indexes.length - 1]; | c;S'36
elseif(startIndex < 0) !MbRI
this.startIndex = 0; m'pihFR:f
else{ _2|,j\f;L
this.startIndex = indexes >@t]M`#&h
j1BYSfX'
[startIndex / pageSize]; U}UIbJD*=
} As"'KR
} @-hy:th#
^#G>P0mG%
publicint getNextIndex(){ @FQ@*XD
int nextIndex = getStartIndex() + U<*dDE~z
kr3ZqMfeI
pageSize; @gZ%>qe
if(nextIndex >= totalCount) }%VHBkuc
return getStartIndex(); YXmLd'F^3
else 1r;Q5[@
return nextIndex; hVd63_OO
} m8FKr/Z-
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publicint getPreviousIndex(){ V482V#BP
int previousIndex = getStartIndex() - .9`.\v6R
n|(Y?`(
pageSize; d~.#K S
if(previousIndex < 0) +jHL==W&
return0; Z!*Wn`d-k
else jML}{>Gy8S
return previousIndex; wt-)5f'{
} 6n>+cX>E
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} <}|+2f233+
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抽象业务类 S]k<Ixvf
java代码: M*%iMz
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/** si)920?E&
* Created on 2005-7-12 `2{x8A
*/ ptX;-'j(
package com.javaeye.common.business; uZi]$/ic
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import java.io.Serializable; nd-y`@z
import java.util.List; {D$#m
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import org.hibernate.Criteria; fAYm3+.l3
import org.hibernate.HibernateException; ij/ |~-!
import org.hibernate.Session; ~fEgrF d
import org.hibernate.criterion.DetachedCriteria; Fj|C+;Q.
import org.hibernate.criterion.Projections; 9=Y-w s
import qY0p)`3!%
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org.springframework.orm.hibernate3.HibernateCallback; sAWUtJ
import gTm[ <Y
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org.springframework.orm.hibernate3.support.HibernateDaoS V{ECDgP
9tWu>keu
upport; cV=h8F
dFK/
import com.javaeye.common.util.PaginationSupport; ?(4=:o
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public abstract class AbstractManager extends NO8)XJ3s
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HibernateDaoSupport { UOi8>;k`
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privateboolean cacheQueries = false; H9F\<5n]-l
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privateString queryCacheRegion; *{/BPc0*
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publicvoid setCacheQueries(boolean f9?\Q'v8
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cacheQueries){ t32
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this.cacheQueries = cacheQueries; V*"-@
} xp.~i*!`
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publicvoid setQueryCacheRegion(String 6=0"3%jn@
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queryCacheRegion){ mfc\w'
this.queryCacheRegion = %77v'Pz1
:q/%uca9
queryCacheRegion; }4b
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} j}ywdP`a
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publicvoid save(finalObject entity){ FCgr
getHibernateTemplate().save(entity);
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} y@Z@ eK3
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publicvoid persist(finalObject entity){ m-Z<zEQ
getHibernateTemplate().save(entity); NitsUg@<
} MH7 n@.t
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publicvoid update(finalObject entity){ ?Dm={S6
getHibernateTemplate().update(entity); P|*c7+q
} 7uQiP&v
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publicvoid delete(finalObject entity){ yq]= +X>(
getHibernateTemplate().delete(entity); 9K,PT.c
} nI]8w6eCV
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publicObject load(finalClass entity, /6",#B}%b
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finalSerializable id){
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return getHibernateTemplate().load n .is+2t
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(entity, id); o?5m^S14[1
} U1nObA
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publicObject get(finalClass entity, I[nSf]Vm>
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finalSerializable id){ orBB5JJ
return getHibernateTemplate().get V9`?s0nn^
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(entity, id); kA/4W^]Ws
} +q*WY*gX
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publicList findAll(finalClass entity){ 6sjd:~J:
return getHibernateTemplate().find("from U/ds(*g@
+%Z#!1u
" + entity.getName()); Wdk]>w
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} <cm(QNdcC
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publicList findByNamedQuery(finalString ^k J>4
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namedQuery){ ibP IT!5c
return getHibernateTemplate ,F%2'W
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().findByNamedQuery(namedQuery); LO;7NK
} f/PqkHF
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publicList findByNamedQuery(finalString query, iWGn4p'
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finalObject parameter){ z!s1$5:" 0
return getHibernateTemplate po9f[/s'+o
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().findByNamedQuery(query, parameter); ]A=yj@o$xN
} lxsn(- j
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publicList findByNamedQuery(finalString query, y
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finalObject[] parameters){ 3d`u!i?/
return getHibernateTemplate k*4!rWr0r&
&K*Kr=9N
().findByNamedQuery(query, parameters); 8-B6D~i
} ;RK;kdZ
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publicList find(finalString query){ #=V\WQb
return getHibernateTemplate().find 4iDqd
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(query); O70#lvsM;
} 8S`
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publicList find(finalString query, finalObject
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parameter){ ~ <36vsk
return getHibernateTemplate().find SM8f"H28
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(query, parameter); ]JR2Av
} JU#m?4g
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public PaginationSupport findPageByCriteria *C);IdhK%y
bU \T
(final DetachedCriteria detachedCriteria){ pAws{3(Q
return findPageByCriteria 9m.MGJbQ_f
[<|$If99\
(detachedCriteria, PaginationSupport.PAGESIZE, 0); sd%m{P2
} 1N[9\Yi
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public PaginationSupport findPageByCriteria Eunmc
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(final DetachedCriteria detachedCriteria, finalint $>7T s>8
{FX]1:
startIndex){ 7p-
RPC
return findPageByCriteria + 9I|Fm
|c>.xt~
(detachedCriteria, PaginationSupport.PAGESIZE, GYg.B<Q.
+z[+kir
startIndex); ==UYjbuU
} Cmp5or6d
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public PaginationSupport findPageByCriteria *+XiBho
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(final DetachedCriteria detachedCriteria, finalint rog1
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pageSize, MsZx 0]
finalint startIndex){ N/'8W9#6
return(PaginationSupport) =XtQ\$Pax
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getHibernateTemplate().execute(new HibernateCallback(){ :+
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publicObject doInHibernate 1]9w9!j
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(Session session)throws HibernateException { 61b*uoq0w?
Criteria criteria = `!spi=f
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detachedCriteria.getExecutableCriteria(session);
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int totalCount = N:CQ$7T{ j
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((Integer) criteria.setProjection(Projections.rowCount <W>A }}q
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()).uniqueResult()).intValue(); c1r+?q$f
criteria.setProjection Qwt0~9n(
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(null); 0w:
3/WO
List items = OR*JWW[]
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criteria.setFirstResult(startIndex).setMaxResults FZW`ADq]
nF_q{e7
(pageSize).list(); ;c>"gW8
PaginationSupport ps = 6VC|]
|*
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new PaginationSupport(items, totalCount, pageSize, ]8fn1Hx\
C
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startIndex); [*Ai@:F
return ps; %)r:!R~R
} R<Mc+{*>
}, true); ;Ce?f=4
} ^N[ Cip}8
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public List findAllByCriteria(final <F(S_w62
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DetachedCriteria detachedCriteria){ !'~L dl
return(List) getHibernateTemplate +uSp3gE"
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().execute(new HibernateCallback(){ _@y uaMoW=
publicObject doInHibernate 6)ibXbH
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(Session session)throws HibernateException { ;y. ;U#O
Criteria criteria = dqJ 8lU?
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detachedCriteria.getExecutableCriteria(session); Im\ ~x~{
return criteria.list(); [8UZ5_1W L
} Tx~w(A4:
}, true); Uz_p-J0
} @IsUY(Gu
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public int getCountByCriteria(final T0")Ryu
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DetachedCriteria detachedCriteria){ Jk-WD"J6
Integer count = (Integer) F<4:P=
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate y705
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(Session session)throws HibernateException { 2F`#df
Criteria criteria = \fEG5/s}T
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detachedCriteria.getExecutableCriteria(session); ]o]`X$n
return lY"l6.c
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criteria.setProjection(Projections.rowCount .z_nW1id
a'|]_`36x
()).uniqueResult(); esA^-$
} APF`b
}, true); PdVx&BL*
return count.intValue(); #*.4Jv<R
} lqv}~MC
} #*qV kPX
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用户在web层构造查询条件detachedCriteria,和可选的 TM{m:I:Z*n
r9u'+$vmF
startIndex,调用业务bean的相应findByCriteria方法,返回一个 ]~dB|WB
EiC["M'}
PaginationSupport的实例ps。 >S`=~4
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ps.getItems()得到已分页好的结果集 cJq{;~
ps.getIndexes()得到分页索引的数组 .Qn#wub
ps.getTotalCount()得到总结果数 ufR>*)_+
ps.getStartIndex()当前分页索引 .O0eSp|e
ps.getNextIndex()下一页索引 9-m_
e=jk6
ps.getPreviousIndex()上一页索引 ,/Gp>Yqx
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HI D6h!
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~!TrC<ft
`{"V(YMEV
,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 8cY5:plK
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一下代码重构了。 ;_<
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我把原本我的做法也提供出来供大家讨论吧: 79)iv+nf\l
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首先,为了实现分页查询,我封装了一个Page类: H/x9w[\+[
java代码: -6F\=
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/*Created on 2005-4-14*/ [C
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package org.flyware.util.page; _%rkN0-(a
r7U[QTM%
/** ?j!/Hc/b4
* @author Joa 9Y# vKb{>
* CD?b.Cxai
*/ |1OF!(:
publicclass Page { w"Zws[pm]
'zt}\ Dt
/** imply if the page has previous page */ P6^\*xkMr
privateboolean hasPrePage; +)(
"!@
Pa\yp?({q
/** imply if the page has next page */ fEK%)Z:0
privateboolean hasNextPage; ABtv|0K
uZ1G,9
/** the number of every page */ <3k9 y^0
privateint everyPage; i}:^<jDv?
EJ:2]!O
/** the total page number */ G
@L`[Wu
privateint totalPage; {
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Y V"
/** the number of current page */ kafj?F
privateint currentPage; [DSzhi]
)hA)`hL
F
/** the begin index of the records by the current kf",/?s2Z
UUgc>
query */ L{6Vi&I84[
privateint beginIndex; ss7Z-A 4z
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)!`>Q|]}Zd
/** The default constructor */ 98l-
public Page(){ 'khhn6itA
+^aM(4K\
} nfr..4,:
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/** construct the page by everyPage /(ArA=#
* @param everyPage /@s(8{;
* */ .TRp74
public Page(int everyPage){ UbwD2>
this.everyPage = everyPage; a*@4W3;7
} ,?!4P+ob
+@C|u'
/** The whole constructor */ qc^qCGy!z
public Page(boolean hasPrePage, boolean hasNextPage, a: OuDjFp
L)Ru]X`
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int everyPage, int totalPage, o{
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int currentPage, int beginIndex){ Q(YQ$i"S
this.hasPrePage = hasPrePage; h)C`w'L
this.hasNextPage = hasNextPage; 9"k^:}8.
this.everyPage = everyPage; :.EVvuXI
this.totalPage = totalPage; yB^_dE
this.currentPage = currentPage; Z0%Qy+%
this.beginIndex = beginIndex; Jyu*{
} _NJq%-,'
6oLq2Z8uP
/** Jq?"?d|:
* @return W[tX%B
* Returns the beginIndex. |b:91l
*/ .EoLJHL
}
publicint getBeginIndex(){ B mxBbg
return beginIndex; 3DO
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} ~~'UQnUN4
d>NM4n[h8
/** ;7Y4v`m
* @param beginIndex %CiZ>`5n#
* The beginIndex to set. n$y)F} .-
*/ 4#y
publicvoid setBeginIndex(int beginIndex){ Od:,r
this.beginIndex = beginIndex; `[Xff24(eb
} #!X4\+)
7Z<ba^r}
/** ?5g0#wqI
* @return 9Iod[ x
* Returns the currentPage. 1tQl^>r16
*/ )9QeVf
publicint getCurrentPage(){ tZ]/?+1G
return currentPage; L.@o
} IZkQmA=
dLMKfh/4Q
/** jQ s"8[=s
* @param currentPage $NtbI:e{
* The currentPage to set. tb-:9*2j-
*/ u/BCl!`
publicvoid setCurrentPage(int currentPage){ 80M"`6
this.currentPage = currentPage; -C|1O%.
} ZsPT!l,
vA*Ud;%R
/** _JjR=
m
* @return KPOr8=Rc
* Returns the everyPage. T.sib&R
*/ TYQ7jt0=.-
publicint getEveryPage(){ E$'Zd,|f=
return everyPage; AVys`{*c
} ljij/ C=
n~g,qEI;<x
/** <y}`PmIM I
* @param everyPage 2,Og(_0>
* The everyPage to set. M@V.?;F},
*/ L"akV,w4p
publicvoid setEveryPage(int everyPage){ 4_E{
this.everyPage = everyPage; y-TS?5Dr]
} SG{> t*E
!?o661+b
/** w>:~Ev]
* @return S(c ,Sinc
* Returns the hasNextPage. Xq9n-;%zL
*/ w~eF0{h
publicboolean getHasNextPage(){ G.3qg%
return hasNextPage; @"9^U_Qf1z
} Sxrbhnx
s!Xj'H7K
/** 0pWF\<IZ
* @param hasNextPage 0B^0,d(s
* The hasNextPage to set. w
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*/ 5JE8/CbH
publicvoid setHasNextPage(boolean hasNextPage){ }vRs n-E@
this.hasNextPage = hasNextPage; /hPgOaB
} +1Ha,Ok
xD}ha
/** +)C?v&N
* @return VuDSjh
* Returns the hasPrePage. M+X>!Os
*/ fA!uSqR$V
publicboolean getHasPrePage(){ #<X+)B6t
return hasPrePage; :xitV]1.
} (c `t'e
qm-G=EX
/** 28u)q2s^W|
* @param hasPrePage Ctpr.
* The hasPrePage to set. ~yH<,e
*/ X'4g\)*
publicvoid setHasPrePage(boolean hasPrePage){ .]+oE$,!
this.hasPrePage = hasPrePage; >y C1X|d~t
} b{|Ha3;w
HtUFl
/** .0l0*~[
* @return Returns the totalPage. Bb^CukS:
* 'u }|~u?m
*/ LXr
yv;H
publicint getTotalPage(){ }Yt/e-Yg%r
return totalPage; a"^0;a
} qJ=4HlLno
UD|Qa
/** [hs_HYqJ
* @param totalPage ]sBSLEie
'
* The totalPage to set. a%"mgCB
*/ !424K-nW
publicvoid setTotalPage(int totalPage){ 1b:3'E.#w
this.totalPage = totalPage; V @A+d[
} (0jT#&#
h}&WBN
} h xO}'`:
h+FM?ct6}
7Q}pKq]P
#Vq9 =Q2
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Y^eN}@]?&
!@ ^6/=
个PageUtil,负责对Page对象进行构造: ci~#G[_$S
java代码: !GqFX+!Ju
_QPqF{iI
5?kfE
/*Created on 2005-4-14*/ ANM#Kx+
package org.flyware.util.page; Z[oF4 z
uzy5rA==
import org.apache.commons.logging.Log; 1qRquY
import org.apache.commons.logging.LogFactory; r
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a5D|#9
/** WAa45G
* @author Joa Aqyw
* u,sR2&Fe
*/ )6OD@<r{
publicclass PageUtil { a+w2cN'
;M:AcQZ|_
privatestaticfinal Log logger = LogFactory.getLog ?b
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X0lPRk53(
(PageUtil.class); uU H4vUa
AUnfhk@$
/** ]juPm8eF
* Use the origin page to create a new page <xI<^r'C9e
* @param page jm}CrqU
* @param totalRecords VW-qQe
* @return hyI7X7Hy
*/ `Ij@;=(
publicstatic Page createPage(Page page, int AI|vL4*Xd
"tJ+v*E
totalRecords){ _olQ;{ U:
return createPage(page.getEveryPage(), &@0~]\,D7
oz)[-
page.getCurrentPage(), totalRecords); ;J%:DD
} ^/f~\#R
NXW*{b
/** I'/3_AX
* the basic page utils not including exception n6/Ous
st-{xC#N#
handler L)e"qC_-
* @param everyPage XkaREE
* @param currentPage uYh!04u
* @param totalRecords ij"~]I
* @return page spEdq}
*/ e &6 %
publicstatic Page createPage(int everyPage, int |Y9>kXM l
&V].,12x
currentPage, int totalRecords){ CMt<oT6.?
everyPage = getEveryPage(everyPage); VY?9|};f
currentPage = getCurrentPage(currentPage); WtT;y|W
int beginIndex = getBeginIndex(everyPage, r&gvP|W%
Iy<>-e"|
currentPage); :U6`n
int totalPage = getTotalPage(everyPage, (MwRe?Ih
gq=t7b
totalRecords); honh'j
boolean hasNextPage = hasNextPage(currentPage, PDNl]?
w"hd_8cO
totalPage); mRk)5{
boolean hasPrePage = hasPrePage(currentPage); 7=^{~5#
kiTC)S=])
returnnew Page(hasPrePage, hasNextPage, _$~>O7
everyPage, totalPage, ).~
"
currentPage, (3Db}Hnn
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beginIndex); 6^`iuC5
} PR:k--)D
.#[ 9q-
privatestaticint getEveryPage(int everyPage){
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return everyPage == 0 ? 10 : everyPage; u]p21)m$x
} 4~fYG| a
l;-Ml{}|0
privatestaticint getCurrentPage(int currentPage){ fzsy<Vl",
return currentPage == 0 ? 1 : currentPage; Ailq,c
} DiFLat]X
I G1];vX
privatestaticint getBeginIndex(int everyPage, int ,\4]uZ<
dC C*|b8h
currentPage){ U^m#!hp
return(currentPage - 1) * everyPage; %:3XYO.w-
} f{BF%;
pMfb(D"
privatestaticint getTotalPage(int everyPage, int EX,>V,.UV
SNj-h>&Mha
totalRecords){ Al>d
21U
int totalPage = 0; qO6M5g:
jJ$\ WUQ.
if(totalRecords % everyPage == 0) g=Xf&}&=x
totalPage = totalRecords / everyPage; IJ^~,+
else z.Cj%N
totalPage = totalRecords / everyPage + 1 ; b3A0o*
0|&@)`
return totalPage; Ho &Q}<(
} O8]e(i
rA~f68h|
privatestaticboolean hasPrePage(int currentPage){ R%UTYRLUn
return currentPage == 1 ? false : true; -WC0W
} ,#Z%0NLe
:_e[xB=Yy
privatestaticboolean hasNextPage(int currentPage, Af3|l
AtQ.H-8r
int totalPage){ I&-r^6Yx
return currentPage == totalPage || totalPage == IuwE&#
<)7aNW.
0 ? false : true; nCQtn%j't
} /7}pReUj
C;W@OS-;
M(X
_I`\E
} B;k'J:-"
__=53]jGE
ibkB>n{(
IkCuw./
h;V4|jM
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 BH:A]#_{
56;u7
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ^r~[3NT
u*C*O4f>OC
做法如下: X1#Ar)
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 J"aw 1
7zu\tCWb
的信息,和一个结果集List: 63l3WvoK
java代码: ?fxM1<8
KqI:g*H'x7
/.]u%;%r[
/*Created on 2005-6-13*/ #/oH #/?
package com.adt.bo; Pe<VPf9+
y3~`qq
import java.util.List; u
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DTO_IP
import org.flyware.util.page.Page; lHM+<Z
Fb{N>*l.
/** +>PsQ^^x
* @author Joa -06G.;W\^
*/ !v8R(
publicclass Result { 5*44QV
u@Hz7Q}
P
private Page page; ?UsCSJ1V
<$s6?6P
private List content; xJ>5 ol
TAG@Ab
/** JwI99I'
* The default constructor #D9.A7fCc5
*/ 'g%:/lwA
public Result(){ CnZ!b_J
super(); f&<+45JI
} JCcYFtW
d88A.Z3w
/** \ ca<L
* The constructor using fields eha|cAq
* w"{DLN[Qw
* @param page a3 }V/MY
* @param content ]N 9N][n
*/ /?;'y,(Q
public Result(Page page, List content){ qur2t8gnxq
this.page = page; )K[\j?
this.content = content;
h(=<-p@
} UVux[qX<
S%- kN;
/** %SC Jmn2
* @return Returns the content.
,IB\1#
*/ wN.S]
publicList getContent(){ @)d_zWE
return content; {D[6=\F
} XP)^81i|
*v%y;^{k[/
/** Mp/l*"(
* @return Returns the page. >@7$=Y>D
*/ *QQeK#$s
public Page getPage(){ ,ayEZ#4.m
return page; QF/ULW0G!
} V8/4:Va7s
- VJx)g
/** jfG of*
* @param content 9s<4`oa
* The content to set. {dZ]+2Z~+
*/ qFWN._R
public void setContent(List content){ ^i|R6oO_5
this.content = content; 8xENzTR
} =.z;:0]'n
Qa,=
/** "}v.>L<P
* @param page v \i"-KH
* The page to set. #][i!9$
*/ *b>RUESF
publicvoid setPage(Page page){ A1/@KC"&{G
this.page = page; US$$ADq
} O q$_ q
} 0BDw}E\
(T*$4KGV
d@ K-ZMq
|'z8>1
2
`>a(
2. 编写业务逻辑接口,并实现它(UserManager, @$jV"Y
"`ftcJUd
UserManagerImpl) >[Vc$[62
java代码: ./ {79
b7>'ARdbzX
*|S6iSn9R!
/*Created on 2005-7-15*/ +4-T_m/W/
package com.adt.service; $6Q^ur:
p?f\/
import net.sf.hibernate.HibernateException; XSC=qg$
u79- B-YW^
import org.flyware.util.page.Page; ^7yt>
ZxNTuGOB:
import com.adt.bo.Result; _f0AV;S:vd
s21}
a,eB
/** *#YZm>h
* @author Joa qA GjR!=^
*/ D#LV&4e>.E
publicinterface UserManager { jM\{*!7b
v\,N"X(,
public Result listUser(Page page)throws eMRH*MyD
Ef#LRcG-Z
HibernateException; ~bZ=]i
C=+9XfP 0
} tle`O)&uo
O#U maNj/
5VV}w R
@N4~|`?U
wS}c\!@<,
java代码: M<Wi:r:
I&+.I K_
X8*g#lO?
/*Created on 2005-7-15*/ uHI(-!O
package com.adt.service.impl; cp@Fj"
~W21%T+
import java.util.List; Q!P%duO
S=k!8]/d|
import net.sf.hibernate.HibernateException; itzUq,T
4<-Kd~uL
import org.flyware.util.page.Page; 8b?nr;@
import org.flyware.util.page.PageUtil; yq-~5ui
,4H? + |!
import com.adt.bo.Result; 6X@z(EEL
import com.adt.dao.UserDAO; NwF"Zh5eMW
import com.adt.exception.ObjectNotFoundException; #p(c{L!
import com.adt.service.UserManager; w80X~
4fKvB@O@.
/** YcA. Bn|as
* @author Joa h q7f"`
*/ Leb
Kzqe
publicclass UserManagerImpl implements UserManager { yF)J7a:U
I#MPJ@*WT
private UserDAO userDAO; %!\=$ s}g
i?/Q7D<P
/** 0i\>(o
* @param userDAO The userDAO to set. pX_
*/ :=hL}(~]
publicvoid setUserDAO(UserDAO userDAO){ h A ){>B<;
this.userDAO = userDAO; iAH,f5T
} 9Vm
aB
)(]rUJ~+~A
/* (non-Javadoc) rpiuFst
* @see com.adt.service.UserManager#listUser 7SHllZ
f4p*!e
(org.flyware.util.page.Page) ?c?@j}=?yY
*/ t#.}0Te7
public Result listUser(Page page)throws eA1g}ipm
ahXcQ9jzFi
HibernateException, ObjectNotFoundException { *R+M#l9D`
int totalRecords = userDAO.getUserCount(); ug]2wftlQ
if(totalRecords == 0) #+o$Tg
throw new ObjectNotFoundException OFr"RGW"
2e\"?y OD
("userNotExist"); q%G[tXw
page = PageUtil.createPage(page, totalRecords); = -oP,$k
List users = userDAO.getUserByPage(page); gba1R
returnnew Result(page, users); h~Ir=JV
} p|gVIsg[-e
-F/)-s6#!'
} 93n%:?l"<W
cy@oAoBq
_kBmKE
e5AsX.kvB
.*N,x(V
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fP<==DK
F7<M{h5s
询,接下来编写UserDAO的代码: gA=Pz[i)p
3. UserDAO 和 UserDAOImpl: $E[O}+L$#
java代码: jy~hLEt7
Bj{J&{
)Jvo%Y
/*Created on 2005-7-15*/ t~qSiHw
package com.adt.dao; n=b!c@f4
?6*\M
import java.util.List; L__{U_p
gGNo!'o
import org.flyware.util.page.Page; R}(Rv3>Xx
T=w0T-[f
import net.sf.hibernate.HibernateException; YP!}Bf
!JdZ0l
/** Zah<e6L
* @author Joa 4NRj>y
*/ wy|b Hkr_
publicinterface UserDAO extends BaseDAO { O\q6T7bfRW
"uZ^zV`"
publicList getUserByName(String name)throws >G1]#'6;
YO.ddy*59
HibernateException; Rex86!TO
, MqoX-+
publicint getUserCount()throws HibernateException; 'ym Mu}q
V9KRA 1
publicList getUserByPage(Page page)throws ??Urm[Y.Z
0f_`;{
HibernateException; 8fQfu'LyjY
B !x6N"
} `}ZtK574
uu-M7>+
"KCG']DF
?;w`hA3ei
0T@axQ[%
java代码: AH#a+<;a
(uHyWEHt
c=-qbG0`
/*Created on 2005-7-15*/ s{c|J#s
package com.adt.dao.impl; +u |SX/C
\ %xku:
import java.util.List; @G>eCj
1uyd+*/(xP
import org.flyware.util.page.Page; !mVq+_7]
W3('1
import net.sf.hibernate.HibernateException; L;Yn q<x
import net.sf.hibernate.Query; f6(1jx"
0}`
-<(
import com.adt.dao.UserDAO; 3k8nWT:wT
x'G_z_<V
/** <RbsQ^U
* @author Joa .f[z_%ar
*/ pL*aU=FjQ
public class UserDAOImpl extends BaseDAOHibernateImpl K4RQ{fWpm
y(a>Y! dgU
implements UserDAO { C!1)3w|
'aeuL1mz
/* (non-Javadoc) A58P$#)?
* @see com.adt.dao.UserDAO#getUserByName rNm_w>bq
hq&9S{Ep
(java.lang.String) ]R^xO;g'
*/ PgP\v -.
publicList getUserByName(String name)throws EZp >Cf7
~XXNzz]?
HibernateException { }t|i1{%_
String querySentence = "FROM user in class Vvv;m 5.
McbbEs=)
com.adt.po.User WHERE user.name=:name"; y\9#"=+
Query query = getSession().createQuery "2tKh!?Q
@bAuR
(querySentence); &tiJ=;R1
query.setParameter("name", name); nb*`GE
return query.list(); A^|~>9
} ]Ee$ulJ02
05jjLM'e
/* (non-Javadoc) #g2&x sU
* @see com.adt.dao.UserDAO#getUserCount() cQ`0d3
*/ ra@CouR^c{
publicint getUserCount()throws HibernateException { G~4G$YL*
int count = 0; +'VYqu/
String querySentence = "SELECT count(*) FROM k2#|^N
p%#'`*<a_
user in class com.adt.po.User"; Nn?$}g
Query query = getSession().createQuery D mky!Cp
y M-k]_
(querySentence); _1YC9}
count = ((Integer)query.iterate().next z$ {[Z=
nYBa+>3BDf
()).intValue(); ZC^NhgX
return count; 7^d7:1M
} NE Zu?g
{DUtdu[
/* (non-Javadoc) sfy}J1xIL
* @see com.adt.dao.UserDAO#getUserByPage E>r7A5Uo
eq<!
(org.flyware.util.page.Page) pWH,nn?w.
*/ f)r6F JLU
publicList getUserByPage(Page page)throws b0x%#trA{
['K}p24,
HibernateException { f'M([gn^_
String querySentence = "FROM user in class _lm^v%J$
)$d~HA@B
com.adt.po.User"; #veV {,g
Query query = getSession().createQuery zXbA$c
M7&G9SGZ
(querySentence); T)ISDK4>S"
query.setFirstResult(page.getBeginIndex()) EP+LK?{%
.setMaxResults(page.getEveryPage()); K7nyQGS
return query.list(); 0f'LXn
} qmvQd8|XR
C\dk}A
} G68@(<<Z
(S?DKPnR
D`KaIqLz
L9F71bs59
_8\B~;0
至此,一个完整的分页程序完成。前台的只需要调用 7QoMroR
~_g{P3
userManager.listUser(page)即可得到一个Page对象和结果集对象 R-wz+j#
$~%h4
的综合体,而传入的参数page对象则可以由前台传入,如果用 j"VDqDDz
lWT`y
webwork,甚至可以直接在配置文件中指定。 4:/^ .:
/?Mr2!3N
下面给出一个webwork调用示例: ZNL+w4
java代码: a(ml#-M
tE-g]y3
?zbW z=nq
/*Created on 2005-6-17*/
<$WS~tTz
package com.adt.action.user; (vvD<S*
J(wFJg\/
import java.util.List; k1s5cg=n(
qV/>d',
import org.apache.commons.logging.Log; XP?)xDr8
import org.apache.commons.logging.LogFactory; #VVfHCy
import org.flyware.util.page.Page; x($Djx
=q`T|9v
import com.adt.bo.Result; evNe6J3
import com.adt.service.UserService; )}t't"
import com.opensymphony.xwork.Action; m4Ue)
X>P|-n#
/** <^_crJONom
* @author Joa BBv+*jj
*/ &|db}\jT
publicclass ListUser implementsAction{ vAqj4:j
1xkrhqq
privatestaticfinal Log logger = LogFactory.getLog \j3dB
tc
*c&|2EsZ
(ListUser.class);
5C^@w
=Vazxt@[
private UserService userService; 3JkdP h
fFWi
3.
private Page page; 9cU9'r# h
R^P>yk8
privateList users; GG +T-
%~gI+0HK
/* t8rFn
* (non-Javadoc) HEIg_6sb
* o0|Ex\
* @see com.opensymphony.xwork.Action#execute() I~@8SSO,vH
*/ FF!PmfF'
publicString execute()throwsException{ VuH ->
Result result = userService.listUser(page); ws^Ne30 R
page = result.getPage(); pRL:,q\
users = result.getContent(); )|^8`f
return SUCCESS; rjO{B`sV*
} '[%#70*
fb>$p_s]
/** +@?'dw
* @return Returns the page. x&0kIF'lq
*/ -B1YZ/.rz"
public Page getPage(){ `,wcQ
return page; 8RdP:*HY
} -@''[m .*
m|pTn#*`
/** iQt!PMF.
* @return Returns the users. 1~%o}+#-
*/ S|"Fgoj r
publicList getUsers(){ Dp*:Q){>E
return users; g b -Bxf
} * R%.a^R
z!fdx|PUX
/** I-xwJi9?,
* @param page (NX)oP
* The page to set. ZP"yq6!i
*/ OI+E
(nA
publicvoid setPage(Page page){ $[,l-[-+
this.page = page; BBcj=]"_
} Bwjg#1 E
\}Dpb%^\
/** Dy su{rL
* @param users |K%}}g[<e;
* The users to set. sf`PV}a1
*/ a\=-D:
publicvoid setUsers(List users){ d7* CwY9"
this.users = users; }mKwFVZ
} LZ{YmD&6]
( :{"C6x
/** 80Ag
* @param userService ,'~#Ch
* The userService to set. <"?*zx&