Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 V@%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 UQI
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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{1#~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 6):Xzx,
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。 rk|a5-i
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分页支持类: }"_j0ax
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java代码: Yp1bH+/u
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package com.javaeye.common.util; R?pR xY
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import java.util.List; ;:mu}
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publicclass PaginationSupport { ~e">_;k6
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publicfinalstaticint PAGESIZE = 30; ^$-Ye]<
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privateint pageSize = PAGESIZE; +}@8p[`)
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privateList items; B4ZIURciGz
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privateint totalCount; @I-Lv5
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privateint[] indexes = newint[0]; AIRr{Y
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privateint startIndex = 0; &aG*k*
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public PaginationSupport(List items, int qAY%nA>jO
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totalCount){ 55Gtp\L
setPageSize(PAGESIZE); P0Z!?`e=M
setTotalCount(totalCount); R Oc`BH=
setItems(items); Uxu\u0*
setStartIndex(0); hs+kr?Pg`
} jrMe G.e=D
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public PaginationSupport(List items, int 'ZP)cI:+X
831JwSR
totalCount, int startIndex){ o)Z=m:t,lK
setPageSize(PAGESIZE); Sr_VL:Gg
setTotalCount(totalCount); &miexSNeF
setItems(items); ]N{0:Va@D
setStartIndex(startIndex); 'CR)`G_'[
} +q<B.XxkA
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public PaginationSupport(List items, int z=7|{ G
V5`^Y=X(%
totalCount, int pageSize, int startIndex){ CC^E_j T
setPageSize(pageSize); GV.A+u
setTotalCount(totalCount); TX [%(ft
setItems(items); %A/_5;PZ/
setStartIndex(startIndex); vZj`|
} 2aN<w'pA
Gi2$B76<
publicList getItems(){ t.Nb?/
return items; tw=oH9c80
} bM,1 f/^
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publicvoid setItems(List items){ "=/ f$Xf
this.items = items; kgdT7
} c]-*P7W
q.YfC
publicint getPageSize(){ 4LH[4Yj?`
return pageSize; V5F%_,No
} {LHR!~d}5f
@%ip7Y]e
publicvoid setPageSize(int pageSize){ 7R4z}2F2
this.pageSize = pageSize; a|7a_s4(
} !k3e\v|
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publicint getTotalCount(){ pCh2SQ(Q>
return totalCount; q$(5Vd:
} %V9ZyQg%*
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publicvoid setTotalCount(int totalCount){ WYB{% yf
if(totalCount > 0){ =Z=o#46JY
this.totalCount = totalCount; 5irwz4.4
int count = totalCount / l5xCz=dw
mm[2wfTE
pageSize; EtbnE*S
if(totalCount % pageSize > 0) 7/7Z`
count++; =@2FX&&E_
indexes = newint[count]; )SryDRT
for(int i = 0; i < count; i++){ ~lNsa".c
indexes = pageSize * OU5*9_7.
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i; g_5Q A)4x
} O,aS`u &
}else{ qd3Q}Lk
this.totalCount = 0; ~'37`)]z
} FR2=
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} 3(TsgP>`
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publicint[] getIndexes(){ HbP!KVHyk1
return indexes; su*Pk|6%
} T91moRv
sf&]u;^DY
publicvoid setIndexes(int[] indexes){ .ERO|$fv
this.indexes = indexes; "&Po,AWa
} "-@[R
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publicint getStartIndex(){ }neY<{z
return startIndex; {uzf"%VtP
} >pUtwIP
|rm g#;/D
publicvoid setStartIndex(int startIndex){ PkI:*\R
if(totalCount <= 0) quY:pqG38q
this.startIndex = 0; \&U>LwZd?
elseif(startIndex >= totalCount) N F)~W#
this.startIndex = indexes w]N!S;<N
l;o1 d-n]
[indexes.length - 1]; 4apL4E"r
elseif(startIndex < 0) fb^fVSh>
this.startIndex = 0; mI 74x3 [
else{ vWAL^?HUP
this.startIndex = indexes )GHq/:1W
8WnwQ%;m?
[startIndex / pageSize]; sr8cYLm5R
} sQkhwMg
} H;RwO@v
v:H$<~)E|
publicint getNextIndex(){ #%DE;
int nextIndex = getStartIndex() + 6Ybg^0m
Gz.|]:1
pageSize; Hh+ 2mkg
if(nextIndex >= totalCount) eJg8,7WC
return getStartIndex(); 3Z1CWzq(
else Bve.C
return nextIndex; Bz,?{o6s)Q
} p,#o<W
Mo^ od<
publicint getPreviousIndex(){ ~@}Bi@*
int previousIndex = getStartIndex() - ^0Mt*e{q
ZHa"isl$e
pageSize; $< JaLS
if(previousIndex < 0) z<Nfm
return0; q<M2,YrbAI
else 7Op>i,HZk\
return previousIndex; lnjXDoVb<
}
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\kZ?
} |p ,P46I
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抽象业务类 ;=MU';o
java代码: uLV#SQ=bZN
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/** (JOgy.5C~
* Created on 2005-7-12 a^I\ /&aw'
*/ F'21jy&
package com.javaeye.common.business; ~nay" g:
.:F%_dS D
import java.io.Serializable; %lGl,me H
import java.util.List; r97pOs#5:
EFM5,gB.m
import org.hibernate.Criteria; %iQD /iT5
import org.hibernate.HibernateException; {ttysQ-
import org.hibernate.Session; _z|65H
import org.hibernate.criterion.DetachedCriteria; 7fZDsj:
import org.hibernate.criterion.Projections; |IzPgC
import RMdk:YvBg
YIG~MP
org.springframework.orm.hibernate3.HibernateCallback; I=`U7Bis"
import 3`DQo%<
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org.springframework.orm.hibernate3.support.HibernateDaoS a.k.n<
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upport; T4Pgbop
!$gR{XH$]
import com.javaeye.common.util.PaginationSupport; k%WTJbuG<)
Pd_U7&w,5
public abstract class AbstractManager extends -lY6|79bF
_Tm3<o.
HibernateDaoSupport { qm/22:&v5
x??+~$}\*-
privateboolean cacheQueries = false; Rl?_^dPx
tEvut=k'
privateString queryCacheRegion; Z 2V.3
r@H /kD
publicvoid setCacheQueries(boolean <L8'! q}
,/Z%@-rF
cacheQueries){ K0|FY=#2y
this.cacheQueries = cacheQueries; &5B'nk"
} Kqb#_hm
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publicvoid setQueryCacheRegion(String ];[}:f
^ @s1Z7
queryCacheRegion){ Y!w`YYKP
this.queryCacheRegion = vc;$-v$&
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queryCacheRegion; Z&+ g;(g
} 6H.0vN&
@k,#L`3^
publicvoid save(finalObject entity){ k8&;lgO'
getHibernateTemplate().save(entity); 3nO]Ge"w'n
} d;Ym=YHJtn
5H<m$K4z
publicvoid persist(finalObject entity){ l*Gvf_UH
getHibernateTemplate().save(entity); NX*Q F+
} !C':
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publicvoid update(finalObject entity){ NvceYKp:
getHibernateTemplate().update(entity); 3w*R&
} AUG#_HE]k
oM>l#><nq
publicvoid delete(finalObject entity){ fgp]x&5Q
getHibernateTemplate().delete(entity); |.: q
} )0]'QLH
r,73C/*&/
publicObject load(finalClass entity, V(I8=rVH
G"qvz{*
finalSerializable id){ gV's=cQ
return getHibernateTemplate().load mp1@|*Sn
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(entity, id); G5BfNU
} #jvtUS \
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publicObject get(finalClass entity, hn
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finalSerializable id){ gh]cXuph
return getHibernateTemplate().get BA:VPTZq
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(entity, id); r(TIw%L$
} UcHJR"M~c
Q->sV$^=T
publicList findAll(finalClass entity){ \;Biq`
return getHibernateTemplate().find("from q"lSZ;
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kiaw4_
" + entity.getName()); `Y$4 H,8L
} D%pF;XY
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_
publicList findByNamedQuery(finalString "%w u2%i
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namedQuery){ BL}\D;+t
return getHibernateTemplate H/
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().findByNamedQuery(namedQuery); v@L;x [Q
} %J?xRv!
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publicList findByNamedQuery(finalString query, *w\W/ Y
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finalObject parameter){ g*_&
return getHibernateTemplate 83_h J
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().findByNamedQuery(query, parameter); G9cUD[GB
} 6A-|[(NS
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publicList findByNamedQuery(finalString query, 7Ovi{xd@
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finalObject[] parameters){ &j"?\f?
return getHibernateTemplate ^}o 2
{4Cmu;u
().findByNamedQuery(query, parameters); dR,fXQm
} /
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publicList find(finalString query){ ]2KihP8z
x
return getHibernateTemplate().find _]H&,</
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(query); %7.30CA|#
} VpDbHAg
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publicList find(finalString query, finalObject `M8i92V\qY
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parameter){ 9WyhZoPD*
return getHibernateTemplate().find rjYJs*#
z<?)Rq"
(query, parameter); -FaJ^CN~
} }K|oicpUg
h S&R(m
public PaginationSupport findPageByCriteria &V/MmmT
(O3nL.
(final DetachedCriteria detachedCriteria){ u^ ~W+
return findPageByCriteria UP,c |
XXa|BZ1RX
(detachedCriteria, PaginationSupport.PAGESIZE, 0); (*iHf"=\
} h2d(?vOT
VMWf>ZU
public PaginationSupport findPageByCriteria $ddCTS^
4,DeHJjAlE
(final DetachedCriteria detachedCriteria, finalint &D*b|ilvc
( a#BV}=
startIndex){ aPL+=5 8r
return findPageByCriteria 4.t-i5
H/M@t\$Dc
(detachedCriteria, PaginationSupport.PAGESIZE,
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startIndex); ]h5tgi?_l
} G4"F+%.
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public PaginationSupport findPageByCriteria pEA:L$&
utV_W&
(final DetachedCriteria detachedCriteria, finalint 6Z"X}L,*
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pageSize, Zj'9rXhrM1
finalint startIndex){ X"%gQ.1|{j
return(PaginationSupport) ;aVZ"~a+\
cw
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getHibernateTemplate().execute(new HibernateCallback(){ f3y=Wxk[
publicObject doInHibernate b&U62iq
^U/O!GK
(Session session)throws HibernateException { K{+2G&i
Criteria criteria = 493*{
;!Fn1|)
detachedCriteria.getExecutableCriteria(session); p5*EA
x
int totalCount = a d\ot#V
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((Integer) criteria.setProjection(Projections.rowCount B%68\
8 LCb+^
()).uniqueResult()).intValue(); #GFr`o0$^
criteria.setProjection Wx#;E9=Im
CWKm(@"5
(null); gjlx~.0d
List items = E"IZ6)Q
Q+{n-? :
criteria.setFirstResult(startIndex).setMaxResults Q/Rqa5LI:
#5uOx(>
(pageSize).list(); 2~[juWbz
PaginationSupport ps = \{NO?%s0p
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new PaginationSupport(items, totalCount, pageSize, 8{ I|$*nB
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startIndex); R.3q0yZ
wF
return ps; x?<FJ"8"k
} [#iz/q~}
}, true); 5bb(/YtFy
} "J1
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public List findAllByCriteria(final Iu6
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DetachedCriteria detachedCriteria){ : rVnc =k
return(List) getHibernateTemplate Ho]su?
),!qTjD
().execute(new HibernateCallback(){ St^5Byd<
publicObject doInHibernate Uw:"n]G]D?
'N(R_q6MW
(Session session)throws HibernateException { {.]7!ISl5
Criteria criteria = 'c~4+o4co
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detachedCriteria.getExecutableCriteria(session); !@"OB~
return criteria.list(); VtohL+
} L RF103nw
}, true); !`r$"}g
} v` r:=K
V~ _>U}
public int getCountByCriteria(final 4&iCht
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DetachedCriteria detachedCriteria){ `0R./|bv\I
Integer count = (Integer) E(|>Ddv B&
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getHibernateTemplate().execute(new HibernateCallback(){ fB,_9K5i
publicObject doInHibernate LH6vLuf
t$ *0{w
E
(Session session)throws HibernateException { >R=|Wo`Ri
Criteria criteria = T]$U""
| f##5fB
detachedCriteria.getExecutableCriteria(session); BJ0?kX@
return j+YJbL v
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criteria.setProjection(Projections.rowCount wyG;8I
-F>jIgeC2v
()).uniqueResult(); :hA#m[
} 3uMy]HUQ
}, true); i mM_H;-X
return count.intValue(); [S<";l8
} l;V173W=&
} .e5Mnd%$M
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用户在web层构造查询条件detachedCriteria,和可选的 9>$p
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 4.(4x&
BORA(,
PaginationSupport的实例ps。 Rva$IX^]
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ps.getItems()得到已分页好的结果集 mcok/,/
ps.getIndexes()得到分页索引的数组 zn(PI3+]!
ps.getTotalCount()得到总结果数 )CyS#j#=
ps.getStartIndex()当前分页索引 ze;KhUPRm
ps.getNextIndex()下一页索引 @lt#Nz
ps.getPreviousIndex()上一页索引 3N:D6w-R
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 U%<Inb}ad
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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 RFH0
Ca3~/KrM
一下代码重构了。 s9d_GhT%-
v.ui!|c
我把原本我的做法也提供出来供大家讨论吧: yOKI*.}
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首先,为了实现分页查询,我封装了一个Page类: FCn_^l)EA
java代码: =I~mKn
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/*Created on 2005-4-14*/ 3yXY.>'
package org.flyware.util.page; ]0\MmAJRn
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/** xP,hTE
* @author Joa zv"Z DRW
* Qw)c$93
*/ "wHFN>5B
publicclass Page { eR" <33{
9&ids!W~yx
/** imply if the page has previous page */ kSh( u
privateboolean hasPrePage; *WT`o>
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/** imply if the page has next page */ = 9]~yt
privateboolean hasNextPage; {.\TtE
(!N|Kl
/** the number of every page */ 0K2`-mL
privateint everyPage; r0gJpttDl
o0vUj
/** the total page number */ :08,JL{
privateint totalPage; baK$L;Xo:
&JI8]JmU)
/** the number of current page */ 6i~WcAs
privateint currentPage; 3Ims6I]
{!dVDf_
/** the begin index of the records by the current :Zz
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C 6AUNRpl
query */ ,WB{i^TD
privateint beginIndex; \} :PLCKT
cjIh}:|'
NTI+
/** The default constructor */ 3kMf!VL
public Page(){ j^2wb+`
j ?(&#
} 0=E]cQwh
4Wm@W E
/** construct the page by everyPage l2P=R)@{
* @param everyPage 'CkIz"Wd
* */ $'hEz/
public Page(int everyPage){ n#OB%@]<V
this.everyPage = everyPage; %Q dn
} q(2'\ _`u
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/** The whole constructor */ 8q}q{8
public Page(boolean hasPrePage, boolean hasNextPage, C&rkvM8
_t #k,;
R',rsGd`6j
int everyPage, int totalPage, hNmJ!Uo
int currentPage, int beginIndex){ 'u |c
this.hasPrePage = hasPrePage; K}MK<2vU
this.hasNextPage = hasNextPage; +s DV~\Vu
this.everyPage = everyPage; l&Q`wR5e
this.totalPage = totalPage; zv,jM0-
this.currentPage = currentPage; (S\[Y9
this.beginIndex = beginIndex; l#Y,R 0
} ~gZLY ls
FSW_<%
/** <s<n
* @return AogVF
* Returns the beginIndex. 9H`XeQ.
*/ *]/zc1Q4M
publicint getBeginIndex(){ G^4hd i3@
return beginIndex; GM f
`A,>
} 'XP7"
N47O
qm8B8&-
/** 41?HY{&2
* @param beginIndex qL3;}R
* The beginIndex to set.
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*/ N.{H,oO `
publicvoid setBeginIndex(int beginIndex){ JL}_72gs
this.beginIndex = beginIndex; c>:wd@w
} Hp!-248 S
lbl?k5
/** hxd`OG<gF
* @return ,,Q O^j]4~
* Returns the currentPage. f=gW]x7'R+
*/ J({Xg?
publicint getCurrentPage(){ CiLg]va
return currentPage; {~"/Y@&]R
} &n}f?
`l){!rg8IC
/** `yXg{lk
* @param currentPage O6a<`]F
* The currentPage to set. P& -Qc
*/ /saIs%(fU
publicvoid setCurrentPage(int currentPage){ Tc &z:
this.currentPage = currentPage; /dQl)tL
} Ed,~1GanY
JZ*/,|1}EC
/** +tIF
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* @return L<-_1!wh
* Returns the everyPage. 2E/"hQw
*/ a /l)qB#
publicint getEveryPage(){ lN?qp'%H`
return everyPage; _w(7u(Z
} xU>WEm2
vkd.)x`J,
/** 5Y'qaIFR
* @param everyPage (%e.:W${
* The everyPage to set. xPk8$1meZM
*/ E+R1 !.
publicvoid setEveryPage(int everyPage){ OSWYGnZg
this.everyPage = everyPage; YYl 4"l
} A8fOQ
aa?b`[Xa
/** ZQoU3AD;
* @return [.'|_l
* Returns the hasNextPage. QP^Cx=
*/
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publicboolean getHasNextPage(){ otl0JHt*+
return hasNextPage; LX7FaW
} |\<`Ib4j
X!Mx5fg
/** k)= X}=w
* @param hasNextPage W*4-.*U8a
* The hasNextPage to set. +xSHL|:b
*/ o]` *M|
publicvoid setHasNextPage(boolean hasNextPage){ uK#4(eY=W
this.hasNextPage = hasNextPage; ] =xE
} " 4K(jXq|
/-ch`u md
/** BNl5!X^{
* @return Z!#!Gu*V
* Returns the hasPrePage. ,p@y]
cr
*/ ./k/KSR
publicboolean getHasPrePage(){ I^]2K0+x x
return hasPrePage; axRV:w;E<
} ZrxD`1L
ia~HQ$'+n
/** *@r/5pM2}
* @param hasPrePage e*(!^Q1
* The hasPrePage to set. Eh;'S"{/?j
*/ mpEK (p
publicvoid setHasPrePage(boolean hasPrePage){ Ae^~Cz1qz
this.hasPrePage = hasPrePage; 3cyHfpx-W
} dulI&_x
eRstD>r
/** y8Z_Itlf
* @return Returns the totalPage. hh)`645=x
* C12Fl
*/ Oo8VeRZ
publicint getTotalPage(){ V/LLaZTE
return totalPage; Nk
8 B_{
} ?.-wnz
mh{d8<Q2
/** ]G=L=D^cK
* @param totalPage \*y-g@-{W$
* The totalPage to set. =/+-<px
*/ F>6|3bOR
publicvoid setTotalPage(int totalPage){ (sTpmQx,b
this.totalPage = totalPage; )0W{]2
} f#"J]p
YnS#H"
} 5iw<>9X*
SC!RbW@3
Uh4%}-;
7~%?#
x7w4[QYw
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 6qpJUkd
t?&|8SId
个PageUtil,负责对Page对象进行构造: :$|HNeDO
java代码: NC`aP0S
2'\H\|
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/*Created on 2005-4-14*/ t!X.|`h
package org.flyware.util.page; EhvX)s
P{jbl!UD7
import org.apache.commons.logging.Log; u8g~
import org.apache.commons.logging.LogFactory; "ycJ:Xv49
8z`G,qh
/** 9uO 2Mm
* @author Joa W:nef<WH
* *W1dG#Np}
*/ @)M9IOR
publicclass PageUtil { EU;9*W<
ZzpUUH/r
privatestaticfinal Log logger = LogFactory.getLog EjR9JUu
]Sz:|%JP1
(PageUtil.class); uym*a4J
XJ\DVZ
/** (gU!=F?#m
* Use the origin page to create a new page NB#OCH1/9
* @param page j0aXyLNX
* @param totalRecords m,w A:o$'
* @return h"Q8b}$^)
*/ #L;dI@7C
publicstatic Page createPage(Page page, int q!7ANib6O
pa3{8x{9m
totalRecords){ P>D)7V9Hh
return createPage(page.getEveryPage(), lNh70G8^p
p38-l'{#
page.getCurrentPage(), totalRecords); -f^tE,-
} b\!_cb~ "@
ie95rZp
/** o#Dk&
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* the basic page utils not including exception "Gzz4D
ZvX*t)VjTz
handler _ <V)-Y
* @param everyPage I;(L%TT `
* @param currentPage |aS.a&vwR
* @param totalRecords B dfwa
* @return page -@2iaQ(5a2
*/ -d/
=5yxL
publicstatic Page createPage(int everyPage, int $8h%a
8I
9Q.Yl&A
currentPage, int totalRecords){ :eCwY
everyPage = getEveryPage(everyPage); ec;o\erPG
currentPage = getCurrentPage(currentPage); +TL%-On
int beginIndex = getBeginIndex(everyPage, !9e=_mY
J*A,o~U|
currentPage); v ;{#Q&(
int totalPage = getTotalPage(everyPage, EME|k{W
LonxT&"!D
totalRecords); a58H9w"u)
boolean hasNextPage = hasNextPage(currentPage, uH^-R_tQ
<'Eme
totalPage); ;igIZ$&
boolean hasPrePage = hasPrePage(currentPage); vA{-{Q
.~;\eW [
returnnew Page(hasPrePage, hasNextPage, :3Ox~o
everyPage, totalPage, ? OM!+O
currentPage, M7~2iU<#
Wn2NMXK
beginIndex); ]_gU#,8
} q<|AZ2Ai
JH9J5%sp
privatestaticint getEveryPage(int everyPage){ K\r8g=U
return everyPage == 0 ? 10 : everyPage; {JT&w6Jz
} FW4<5~'
ES7s1O$#
privatestaticint getCurrentPage(int currentPage){ v\ )W?i*l
return currentPage == 0 ? 1 : currentPage; $6 f3F?y7
} {;1\+f
=dKtV.L
privatestaticint getBeginIndex(int everyPage, int %tGO?JMkd
1))8
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currentPage){ x 9fip-
return(currentPage - 1) * everyPage; ZY+qA
} "!^"[mX4
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privatestaticint getTotalPage(int everyPage, int NXrlk
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totalRecords){ Y$_B1_
int totalPage = 0; PJH&
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if(totalRecords % everyPage == 0) #"~<HG}bR/
totalPage = totalRecords / everyPage; F JyT+
else } q8ASYNc
totalPage = totalRecords / everyPage + 1 ; Q;rX;p^W
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return totalPage; 6i/(5 nQ
} ?UoBV$
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privatestaticboolean hasPrePage(int currentPage){
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return currentPage == 1 ? false : true; @o`AmC.
8
} G 3ptx!
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privatestaticboolean hasNextPage(int currentPage, |+9&rAg
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int totalPage){ 3Y$GsN4ln
return currentPage == totalPage || totalPage == D0f] $
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0 ? false : true; tCt#%7J;a
} X&H"51
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} ox.F%)eQ
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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。 %W S+(0*1
K|=A:
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 _+MJ%'>S
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做法如下: aN3;`~{9
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 E]r?{t`]
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的信息,和一个结果集List: wMN]~|z>
java代码: _aeBauD
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;
/*Created on 2005-6-13*/ 5"H=zJ=r
package com.adt.bo; '|=;^Z7.K
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import java.util.List; F:DrX_O%
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import org.flyware.util.page.Page; Flb&B1
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/** ?aMOZn?
* @author Joa ;dhQN}7
*/ 08{@rOr
publicclass Result { /qw.p#
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private Page page; i@J;G`
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private List content; TL#3;l^
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/** 6W
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* The default constructor i}?>g -(
*/ a'IdYW0
public Result(){ :BTq!>s
super(); zx7{U8*`<
} dgePPhj
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/** :Ux_qB
* The constructor using fields jZ;
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* vr^qWn
* @param page 40
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* @param content /u+e0BHo
*/ ReeH@.74
public Result(Page page, List content){ ;*&-C9b
this.page = page; ,7b[!#?8
this.content = content; #3d(M
} )\^-2[;
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/** 5/z/>D;
* @return Returns the content. )sp+8
*/ 0qT%!ku&
publicList getContent(){ 7t_^8I%[
return content; KY]C6kh
} s"?3]P
3oG,E;(
/** {FTqu.
* @return Returns the page. HUO j0T
*/ C{wEzM:
public Page getPage(){ pY$Q
return page; OK
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} xAP+FWyV
5rUdv}.
/** C2)2)
* @param content 6\S~P/PkE
* The content to set. W`*r>`krVJ
*/ H7+,*
public void setContent(List content){ .w,q0<}
this.content = content; dGTsc/$
} :P=(k2
Oz#{S:24M+
/** pFz`}?c0
* @param page S>;
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* The page to set. VOh4#%Vj
*/ $xdy&
publicvoid setPage(Page page){ VgS_s k
this.page = page; $
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} _oDz-
} t<?,F
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t@+}8^M
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2. 编写业务逻辑接口,并实现它(UserManager, ?#Q #u|~
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UserManagerImpl) zs#@jv$
java代码: yJe>JK~)
R
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/*Created on 2005-7-15*/ VTHH&$ZNq
package com.adt.service; (0kK_k'T
v1,oilL
import net.sf.hibernate.HibernateException; H~z`]5CN
VBcPu
import org.flyware.util.page.Page; zT?D<XW>1
P J[`|
import com.adt.bo.Result; WvZ8/T'x
-!]ZMi9
/** ^@NU}S):yN
* @author Joa g5r(>, vY
*/ G?Hdq;
publicinterface UserManager { ZO$%[ftb
c<$OA=n
public Result listUser(Page page)throws )p%E%6p
P\)iZiGc
HibernateException; )q3p-)@kQ
}txX;"/
} >`ZyG5
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wZZ t
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XACm[NY_
java代码:
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mF^v ~
/*Created on 2005-7-15*/ 0b(N^$js'
package com.adt.service.impl; Z!X0U7&U
^eYVWQ'
import java.util.List; b(O3@Q6[
Bh]P{H%
import net.sf.hibernate.HibernateException; NGO fb
oIj#>1~c%
import org.flyware.util.page.Page; S\!ana])
import org.flyware.util.page.PageUtil; o`N9!M
"vE4E|
import com.adt.bo.Result; w!clI8v/
import com.adt.dao.UserDAO; j^rIH#V
import com.adt.exception.ObjectNotFoundException; )
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import com.adt.service.UserManager; l$bu%SZ
>]5P
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/** }s<4{:cv+
* @author Joa Y#$%iF
*/ o"R7,N0rB
publicclass UserManagerImpl implements UserManager { ur7q [n
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private UserDAO userDAO; 2'MZ s]??w
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/** ':m,)G5&
* @param userDAO The userDAO to set. a\YV3NJ/A
*/ oJ|j#+Ft
publicvoid setUserDAO(UserDAO userDAO){ (|1A?@sJ#h
this.userDAO = userDAO; +l{=
} e|WJQd4+S
.O}%
/* (non-Javadoc) i5?q,_
* @see com.adt.service.UserManager#listUser @eIJ]p
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(org.flyware.util.page.Page) vJOw]cwq
*/ xCl1g4N
public Result listUser(Page page)throws d8=x0~7
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HibernateException, ObjectNotFoundException { JKmIvZ)8
int totalRecords = userDAO.getUserCount(); C-6F]2:
if(totalRecords == 0) iaE^a^*
throw new ObjectNotFoundException 3H6lBF
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("userNotExist"); l &5QZI0I
page = PageUtil.createPage(page, totalRecords); $jqq
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List users = userDAO.getUserByPage(page); 8jo p_PG'
returnnew Result(page, users); 8~z~_TD6m@
} J!pygn O
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} "PTZ%7YH}
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fnX`Q[b4\A
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 (I{rLS!o,L
xQXXC|T
询,接下来编写UserDAO的代码: "x*egI
3. UserDAO 和 UserDAOImpl: sjwo/+2
java代码: _zn.K&I-*k
cacr=iX
p=GBUII #
/*Created on 2005-7-15*/ yiC^aY=-
package com.adt.dao; z(Pe,zES
:L RYYw
import java.util.List; >TnTnF WX
a>]uU*Xm
import org.flyware.util.page.Page; ?Unb?
{,&2
kJzoFFWo$
import net.sf.hibernate.HibernateException; }v!$dr,j'
b TM{l.Aq3
/** jW3!6*93
* @author Joa *@v)d[z_
*/ T| V:$D'
publicinterface UserDAO extends BaseDAO { ke]Lw
o(LFh[
publicList getUserByName(String name)throws Ix!Iw[CNd
_c*=4y
HibernateException; MVTMwwO \[
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publicint getUserCount()throws HibernateException; F6OpN"UM'
?Exv|e
publicList getUserByPage(Page page)throws r1.nTO%
4c$ zKqz
HibernateException; w' OXlR
(k) l=]`}
} NI#:|}CYS
XY)&}u.
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Hl/
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];a=Pn-:}G
java代码: D 38$`j
h[1MtmNw
D@|W<i-
/*Created on 2005-7-15*/ )5%'.P>
package com.adt.dao.impl; \h D dU+
o/6-3QUak
import java.util.List; Wi2WRJdyu
Q6AC(n@:FV
import org.flyware.util.page.Page; rI>aAW'
feNdMR7eM
import net.sf.hibernate.HibernateException; :x{NBvUIc
import net.sf.hibernate.Query; ,M6Sy]Aj
'wI"Bo6e
import com.adt.dao.UserDAO; "
'6;/N
? glSC$b
/** gb> }v7
* @author Joa wX[8A/JPD
*/
\ 3?LqJ
public class UserDAOImpl extends BaseDAOHibernateImpl [}8|R0KF
W$rH"_@m
implements UserDAO { M^iU;vo
Tekfw
/* (non-Javadoc) rN<