Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 jx]P: ]
BMy3tyO
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 TI8r/P?
]V
'gvR?[!t
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 mL=d EQ
ocFk#FW
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 z
-!w/Bv@
Aeb(b+=
。 XzHR^^;u"*
b:D92pH
分页支持类: 8.[F3Tk=
S0)JIrrHC
java代码: &CQO+Yr$l
Y.\x.Hg
$[A\i<#
package com.javaeye.common.util; tqZ+2c<W3
NS~;{d\
import java.util.List; DK\XC%~m
\xj;{xc
publicclass PaginationSupport { +yp:douERi
:-B+W9'5
publicfinalstaticint PAGESIZE = 30; d=PX}o^
N+=|WeZ
privateint pageSize = PAGESIZE; 80Dn!9j*
[/CGV8+
privateList items; a:fP
U}RBgPX!
privateint totalCount; UowvkVa
y
%Q. (
privateint[] indexes = newint[0]; <Gi%+I@szl
+cfEyiub
privateint startIndex = 0; z*EV>Y[
y:W6;R
public PaginationSupport(List items, int V0=%$tH
[b:&y(
totalCount){ gvA}s/
setPageSize(PAGESIZE); -2M~KlYl
setTotalCount(totalCount); S^eem_C
setItems(items); x9vSekV
setStartIndex(0); G}fBd
} @kWL "yy,
+e-F`k
public PaginationSupport(List items, int x#J9GP.
gSz<K.CT
totalCount, int startIndex){ x9"Cm;H%
setPageSize(PAGESIZE); YQn<CjZ8af
setTotalCount(totalCount); "XR=P>
xk
setItems(items); +?$J8Paf
setStartIndex(startIndex); *Jd"3Si/
} _&uJE&xl}
#i[:oC6m:
public PaginationSupport(List items, int H#~gx_^U
,~1'L6Ri?
totalCount, int pageSize, int startIndex){ L"qJZU
setPageSize(pageSize); zuV%`n
setTotalCount(totalCount); ; :P4~R
setItems(items); 2'DCB{Jv
setStartIndex(startIndex); )l7XZ_gw'
} ;=Ma+d#
*an Ng<@
publicList getItems(){ >fH0>W+!
return items; "' JnFM
}
/MGapmqV9
|9#q7kM
publicvoid setItems(List items){ {A/r)
this.items = items; EtKq.<SJ
} j_~KD}
2R[v*i^S
publicint getPageSize(){ a!9'yc
return pageSize; b=,BLe\
} mn7I# ~
R2,9%!iiX
publicvoid setPageSize(int pageSize){ m+<&NDj.
this.pageSize = pageSize; #\0m(v
} T/_u;My;
BJj'91B[d
publicint getTotalCount(){ H9mN nZ_k
return totalCount; E^1yU
} }QFL
YThVG0I =
publicvoid setTotalCount(int totalCount){
W,xdj! ^t
if(totalCount > 0){ sbW+vc
this.totalCount = totalCount; oY)eN?c
int count = totalCount / o,*m,Qc
/Y#8.sr
pageSize; ;@wa\H[3v2
if(totalCount % pageSize > 0) )A8#cY!<
count++; b`jR("U
indexes = newint[count]; :_8K8Sa
for(int i = 0; i < count; i++){ ;m]V12
indexes = pageSize * ZcN0:xU
|+Y-i4t
i; _:r8UVAT.
} ,:?ibE=
}else{ J,=K1>8s
this.totalCount = 0; hX.cdt_?
} /5NWV#-
} 'Z{`P0/^o`
kL'4m
publicint[] getIndexes(){ ~H}Z;n]H
return indexes; T
lXS}5^
} C4mkt2Eb0a
gP%<<yl
publicvoid setIndexes(int[] indexes){ x{1 v(n8+=
this.indexes = indexes; !> sA.L&=
} ~7:q+\
`<YMkp[
publicint getStartIndex(){ QVT0.GzR
return startIndex; G\sx'#Whc
} w
<r*&
uw+nll*W%
publicvoid setStartIndex(int startIndex){ >z<L 60S
if(totalCount <= 0) q,P.)\0A
this.startIndex = 0; G_F_TNO
elseif(startIndex >= totalCount) *~PB
this.startIndex = indexes mdc?~?? 8
A;co1,]gR
[indexes.length - 1]; -H60T,o
elseif(startIndex < 0) G*=HjLmZg
this.startIndex = 0; !VD$uT
else{ (HAdr5
this.startIndex = indexes ygz2bHpD~
~VsN\! G
[startIndex / pageSize]; w7MRuAJ4
} x1@,k=qrd
} >WZ.Dj0n
F 'uqL+jVO
publicint getNextIndex(){ :` SIuu~@
int nextIndex = getStartIndex() + RuHDAJ"&a
zA#pgX[#
pageSize; b 8@}Jv
if(nextIndex >= totalCount) i+`8$uz
return getStartIndex(); ,a5q62)q
else nAP*w6m0j
return nextIndex; K_MEd1l
} g2f"tu_/%
(Yy#:r;U
publicint getPreviousIndex(){ !XTzsN
int previousIndex = getStartIndex() - %w&+o.k/
y;az&T
pageSize; q,[;AHb
if(previousIndex < 0) !!.@F;]W
return0; jZ~girA
else o6u^hG6~'
return previousIndex; Mc?_2<u-
} 3Dr\ O_`u
3cJ'tRsp<
} #?Ix6 {R
y>C
!cYB
"smU5 s,P
/
B!j`UK
抽象业务类 \4 b^*`d
java代码: 9"[,9HN
PS~_a
YMo8C(
/** E?]$Y[KJKs
* Created on 2005-7-12 gYt=_+-
*/ 5B~]%_gZr
package com.javaeye.common.business; ^qL<=UC.
'A[PUSEE
import java.io.Serializable; +P))*0(c_
import java.util.List; }X9&!A8z
P*k n}:
import org.hibernate.Criteria; 3uw3[
SR1
import org.hibernate.HibernateException; N!7?D'y
import org.hibernate.Session; l(1.Ll
import org.hibernate.criterion.DetachedCriteria; ` 0@m,
import org.hibernate.criterion.Projections; 3X Y"s"
import 3=wcA/"!
[Vbdsu9
org.springframework.orm.hibernate3.HibernateCallback; @Ov}X]ELi
import 7b~uU@L`
m2m
;|rr
org.springframework.orm.hibernate3.support.HibernateDaoS ,tXI*R
-medD G
upport; $\m:}\%p
c{kpgN
import com.javaeye.common.util.PaginationSupport; LTf)`SN %'
<mJ8~
public abstract class AbstractManager extends 0=+feB1T
z$QoMq]
HibernateDaoSupport { GN(,` y
+/_XSo
privateboolean cacheQueries = false; iklZ[G%A0
l>|scs;TI
privateString queryCacheRegion; ~;b}_?%o
9<&*iIrM
publicvoid setCacheQueries(boolean kh}h(z^
fbM>jK
cacheQueries){ ShQ! '[J
this.cacheQueries = cacheQueries; +6:
} oHfr
glGX
#)L}{mHLM-
publicvoid setQueryCacheRegion(String E\}A<r
5ms]Wbh)
queryCacheRegion){ +L=Xc^
this.queryCacheRegion = E
6#/@C,
md bi@ms@
queryCacheRegion; BJ_"FG
} jcC"vr'u|
) M8,Tv*~
publicvoid save(finalObject entity){ zv"NbN
getHibernateTemplate().save(entity); SWtqp(h]'
} Xtz29
mCn:{G8+
publicvoid persist(finalObject entity){ .Tl,Ek(
getHibernateTemplate().save(entity); ~zZOogM<
} M]%dFQ
{ Mf-?_%
publicvoid update(finalObject entity){ ga,kKPL
getHibernateTemplate().update(entity); x;SY80D
} ~p'|A}9[/
#t2N=3dOj
publicvoid delete(finalObject entity){ Z molL0y
getHibernateTemplate().delete(entity); 97HI9R
} ;wJe%Nw?
-~RGjx
publicObject load(finalClass entity, e2fv%
2WLLI8
finalSerializable id){ nWc@ufY
return getHibernateTemplate().load eKuF7Oo
Sz|kXk6&9
(entity, id); p5"pQeS
} %Cj_z
:W>PKW`^
publicObject get(finalClass entity, =i}lh}(
8,F|*YA
finalSerializable id){ Aua}.Fl,
return getHibernateTemplate().get \HrtPm`e
T++q.oFc
(entity, id); @#^Y#
rxb
} "Uf1;;b
Qe!3ae`Z
publicList findAll(finalClass entity){ ?v:FGO
return getHibernateTemplate().find("from Z{t `f[
PZ#up{[o
" + entity.getName()); BK)<~I
} *Ej;}KSv
0nBDF79
publicList findByNamedQuery(finalString b)#rUI|O
g9;s3qXiG
namedQuery){ MtF^}/0w!`
return getHibernateTemplate =[:E
E`xpZ>$mPx
().findByNamedQuery(namedQuery); a*}>yad
} 4o";p}[b
Cb|1Jtb
publicList findByNamedQuery(finalString query, 2 ( I4h[
-da: j-_
finalObject parameter){ K}
T=j+
return getHibernateTemplate KSS]% 66Y
R-<8j`[0
().findByNamedQuery(query, parameter); Wt@hST
} G{,DoCM5WL
pd`m//G
publicList findByNamedQuery(finalString query, CAx
eJ`Q
r9!s@n
finalObject[] parameters){ 9Nna-}e?W
return getHibernateTemplate uzmYkBv
d@$bPQQ$,
().findByNamedQuery(query, parameters); m<k6oev$
} )FG/
b>i5r$S8G
publicList find(finalString query){ *ZLisq-f
return getHibernateTemplate().find
T*8S7l
T~L V\}h
(query); q$b4S4Z7
} FG!hb?_1
z`$c4p6G6
publicList find(finalString query, finalObject #*w)rGkU2
Ahbh,U
parameter){ {98e_z w
return getHibernateTemplate().find O0
Uh
k'
Fu&r
(query, parameter); bYpeI(zK
} IsJx5GO
PJ?C[+&
public PaginationSupport findPageByCriteria (C
uM*-
SO STtuT
(final DetachedCriteria detachedCriteria){ Ahba1\,N$
return findPageByCriteria Bxw(pACf
Dm}M8`|X
(detachedCriteria, PaginationSupport.PAGESIZE, 0); zkqn>
} 4W49*Je
z%T|L[(6
public PaginationSupport findPageByCriteria fI<d&5&g
]91QZ~4a
(final DetachedCriteria detachedCriteria, finalint ^Z\"d#A
.p o,.}
startIndex){ &Ruq8n<
return findPageByCriteria '/X]96Ci7
!J!&JQ|
(detachedCriteria, PaginationSupport.PAGESIZE, v.4G>0 0^
n53c}^
startIndex); /J!:_Nq
} @x743}Y\
QS\wtTXj
public PaginationSupport findPageByCriteria P zM yUv
FIVC~LDd
(final DetachedCriteria detachedCriteria, finalint k.c.7%|~;
RP+)sCh
pageSize, 2P^qZDG 8I
finalint startIndex){ Wi!"Vcn
return(PaginationSupport) 7Nk|9t
Y6)o7t
getHibernateTemplate().execute(new HibernateCallback(){ KUm?gFh
publicObject doInHibernate P7Qel ,
gJ9"$fIPc
(Session session)throws HibernateException { e3p:lu
Criteria criteria = Ok\X%avq
aHYISjZ]>
detachedCriteria.getExecutableCriteria(session); -/Wf iE
int totalCount = *TI?tD
`]@=Hx(
((Integer) criteria.setProjection(Projections.rowCount 6@8z3JW.A
79d(UG'O
()).uniqueResult()).intValue(); XpE847!soL
criteria.setProjection aH@-"Wi
;y1/b(t
(null); yf8kBT:&S
List items = "8cI]~V
&|RTLGwX
criteria.setFirstResult(startIndex).setMaxResults vlEW{B;)Z
t#t[cgI
(pageSize).list(); gJrWewEe
PaginationSupport ps = Q@NFfJJ
W-&V:S{<
new PaginationSupport(items, totalCount, pageSize, 1 0c.#9$
p nI=
startIndex); )78T+7Kq
return ps; ]cmX f
} uZJfIC<>
}, true); g|$;jQ\_
} \M._x"
ybJ wFZ80
public List findAllByCriteria(final NT5'U
j4#uj[A
DetachedCriteria detachedCriteria){ PR$;*|@
return(List) getHibernateTemplate ^i!6z2/
v0E6i!D/
().execute(new HibernateCallback(){ Hk h'h"_r
publicObject doInHibernate &{+ 0a[rN
y5+%8#3
(Session session)throws HibernateException { {Y Y,{H
Criteria criteria = E0&d*BI2
fbbbTZy
detachedCriteria.getExecutableCriteria(session); Dat',5
return criteria.list(); +0UBP7kn
} 9:VUtx#}2
}, true); 8 p[n>qV9
} Q3&q%n|<
!8cV."~
public int getCountByCriteria(final kC
6*An_f
ykPiZK
DetachedCriteria detachedCriteria){ uh2_Rzln
Integer count = (Integer) 73Jm
fCJjFL:
getHibernateTemplate().execute(new HibernateCallback(){ [?KGLUmTAI
publicObject doInHibernate 5~ :/%+F0=
B,w
ZI4oi*
(Session session)throws HibernateException { O x-eB
Criteria criteria = emnT;kJ>
|b.xG_-s1
detachedCriteria.getExecutableCriteria(session); bP#!U'b" =
return HBtk)
]- `wXi"
criteria.setProjection(Projections.rowCount \y=oZk4
q^EY?;Y
()).uniqueResult(); DmLx"%H3
} |llJ%JhF
}, true); _(kaa WJ
return count.intValue(); 0.n[_?<(
} flFdoEV.U)
} d,JDfG)
@&WHX#
Jut&J]{h
u YT$$'S
G7al@
JDE_*xaUV
用户在web层构造查询条件detachedCriteria,和可选的 VLkAsM5}%
_"yA1D0d_
startIndex,调用业务bean的相应findByCriteria方法,返回一个 e}d(.H%l0
uij^tN%
PaginationSupport的实例ps。 RLnL9)`W
!+^'Ej)z
ps.getItems()得到已分页好的结果集 Y`bTf@EP>
ps.getIndexes()得到分页索引的数组 Op?"G
ps.getTotalCount()得到总结果数 ^sLx3a
ps.getStartIndex()当前分页索引 "W(Ae="60
ps.getNextIndex()下一页索引 +W*~=*h|
ps.getPreviousIndex()上一页索引 y@!o&,,mq
g)#{<#*2
d>8"-$
'"\M`G
k<^M >` $
&EQhk9j
LtMM89u
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }\7UU?@ n
~!r;?38V`
,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 NSB6 2
Kh(`6 f
一下代码重构了。 `/P/2{,~
Wa<<"x$
我把原本我的做法也提供出来供大家讨论吧: i!?gga
Q]xkDr?
首先,为了实现分页查询,我封装了一个Page类: \BXzmok
java代码: +C{-s
vCaN [
:Tg+)c Z
/*Created on 2005-4-14*/ ?";SUku
package org.flyware.util.page; ,=m.WmXE
Jd>~gA}l
/** s51$x M
* @author Joa J @"#
* 5h#h>0F
*/ .w.:o2L
publicclass Page { LJ(WU)CPc
=
(F
/** imply if the page has previous page */ "lL+Heq>V
privateboolean hasPrePage; -y+>^45
: OY~Q3
@
/** imply if the page has next page */ 'cXdc
privateboolean hasNextPage; UUJQc~=
ilL0=[2
/** the number of every page */ "S%t\
privateint everyPage; EX`P(=zD
EbQLMLD%
/** the total page number */ `S@TiD*
privateint totalPage; lZ\8W^
S 13cQ?4
/** the number of current page */ GrL{q;IO
privateint currentPage; 'kZ,:.v
xLz=)k[''
/** the begin index of the records by the current -[V-f> :
^[tE^(|T
query */ ~y!'\d>q<
privateint beginIndex; hJ'H@L7
6@J=n@J$p
ZYwcB]xEz
/** The default constructor */ c~Ka) dF|
public Page(){ m.e]tTe
)?*YrWO{
} I9*cEZ!l=e
o|(5Sr&H
/** construct the page by everyPage NXY jb(4:
* @param everyPage $RPW/Lyiq
* */ }~XWtWbd-
public Page(int everyPage){ 'jtC#:ePK
this.everyPage = everyPage; Wp=3heCa6
} ~f1g"
f&^(f1WO
/** The whole constructor */ pIJXP$v3
public Page(boolean hasPrePage, boolean hasNextPage, 4]y)YNQ(
pE4a ~:
'-;[8:y.
int everyPage, int totalPage, e<L@QNX
int currentPage, int beginIndex){ 7^q~a(j
this.hasPrePage = hasPrePage; {3tzr ;c?
this.hasNextPage = hasNextPage; x%G3L\5
this.everyPage = everyPage; L[G O6l
this.totalPage = totalPage; 6Xlzdt
this.currentPage = currentPage; nVb@sI{{k
this.beginIndex = beginIndex; 0mY Y:?v
} 5</$dcG
,S8 K!
/** @w[i%F,&`
* @return iq(PC3e`V
* Returns the beginIndex. g{65 QP
*/ @X2*O9
publicint getBeginIndex(){ |p11Jt[
return beginIndex; {*ak>Wud
} $cCC
1=dW
V#t_gS
/** T #\
* @param beginIndex "ZuuSi
* The beginIndex to set. &XP(D5lf`B
*/ ff"wg\O4
publicvoid setBeginIndex(int beginIndex){ %@/^UE:
this.beginIndex = beginIndex; J-F".6i5
} G 6sK3K
XIeLu"TSL
/** ~Iu! B
Y
* @return ggr
* Returns the currentPage. ;;Q^/rkC
*/ )O]T}eI
publicint getCurrentPage(){ @;Ttdwg#J
return currentPage; 6o3
bq|
} AlSO
6OES'3 Cy
/** '|C3t!H`
* @param currentPage ly[LF1t
* The currentPage to set. X%1TsCKMj
*/ rH+OXGoB
publicvoid setCurrentPage(int currentPage){ 3FEJ
9ZyG
this.currentPage = currentPage; b'H'QY
} hRcb}>pr
U@lc1#
/** *sho/[~_
* @return ^URCnJ67Se
* Returns the everyPage. mP(3[a_Q
*/ @fL ^I&++
publicint getEveryPage(){ Nk`UQ~g$
return everyPage; Hd|l6/[xz
} p5Q]/DhG
yzA05 npTl
/** {|+Y;V`
* @param everyPage (L_-!=e
* The everyPage to set. !d*[QD8
*/ S2~cAhR|M
publicvoid setEveryPage(int everyPage){ Zo9<96I&
this.everyPage = everyPage; JE?p'77C
} V|7YRa@
L+%"ew
/** )
nfoDG#O
* @return N+-Tp&:wY
* Returns the hasNextPage. XZ
rI w
*/ v0^9"V:y
publicboolean getHasNextPage(){ LSo!_tY
return hasNextPage; 8!g
`bC#%
} S)rZE*~2
z`y9<+
/** E*_^+ %
* @param hasNextPage ));#oQol9
* The hasNextPage to set. 5sD,gZ7
*/ g;IlS*Ld
publicvoid setHasNextPage(boolean hasNextPage){ T)C@6/
this.hasNextPage = hasNextPage; BxY t*b%
} h$>F}n
j
!,J#
r
/** 73WSW/^F
* @return H#-3
* Returns the hasPrePage. cw;wv+|k
*/ ZO}Og&%
publicboolean getHasPrePage(){ #m+!<
return hasPrePage; l{3B}_,
} t<%0eu|
8OfQ :
/** '[F:uA
* @param hasPrePage +)Te)^&v%
* The hasPrePage to set. Z5{a7U4z_
*/ &dtk&P{
publicvoid setHasPrePage(boolean hasPrePage){ <G"cgN#]
this.hasPrePage = hasPrePage; fGgt[f[
} ;?6vKpj;
A=CeeC]}
/** L\yVE
J9x
* @return Returns the totalPage. y>{:[L9*
* :fRXLe1=
*/ mp|pz%U
publicint getTotalPage(){ -@uFRQt
return totalPage; b^Hrzn
}
idmU.`
QbU5FPiN
/** B(
[x8A]
* @param totalPage eh#37*-
* The totalPage to set. FR(W.5[
*/ =O/Bte.
publicvoid setTotalPage(int totalPage){ vNv?trw
this.totalPage = totalPage; T}~TW26v
} BT{;^Hp
J=V
} gmTBT#{6yH
WxdQ^#AE
)cfi@-J+#
g14*6O:
#kg`rrFr
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 _iwG'a[`
4"@<bKx
个PageUtil,负责对Page对象进行构造: aCQtE,.
java代码: NgNGq\!
Hg+<GML
P{L=u74b{x
/*Created on 2005-4-14*/ 7GA8sK
package org.flyware.util.page; Wj{lb_Rj
B|(g?
import org.apache.commons.logging.Log; ! VwU=5
import org.apache.commons.logging.LogFactory; \j)Evjw
-K"'F`;W
/** }v1wpv/b(
* @author Joa >DL
* pjl%Jm
*/ 4Z)4WGp!
publicclass PageUtil { N'^>pSc4W|
:}Jx
privatestaticfinal Log logger = LogFactory.getLog N_t,n^i9>*
(1/Sf&2i
(PageUtil.class); OhF55,[
DF%d/a{]
/** 3)OZf{D[
* Use the origin page to create a new page #86N
!&x
* @param page %cNN<x8
* @param totalRecords gv!8' DKn
* @return Z0|5VLk,<{
*/ pP\Cwo #,
publicstatic Page createPage(Page page, int !3Dq)ebBz
o7y<Zd`Bj
totalRecords){ J?4{#p
return createPage(page.getEveryPage(), $CcjuPsK
%wD#[<BGn>
page.getCurrentPage(), totalRecords); yCX5
5:
}
l\U
Q2i
37bMe@W
/** Iil2R}1
* the basic page utils not including exception WR+j?Fcf
#-az]s|N
handler ^[ae
)}
* @param everyPage {9IRW\kn
* @param currentPage W5jwD
* @param totalRecords , 3R=8
* @return page Sn:>|y~
*/ I2}W /}
publicstatic Page createPage(int everyPage, int 0AZ9I!&i
wG3L+[,
currentPage, int totalRecords){ .=y=Fv6X
everyPage = getEveryPage(everyPage); 09Hrn
currentPage = getCurrentPage(currentPage); D#jwI,n}x
int beginIndex = getBeginIndex(everyPage, 9#E *o~1
Khq\@`RaT
currentPage); ci,(]T+!
int totalPage = getTotalPage(everyPage, $`pf!b2Z
UBo0c?,4
totalRecords); 1N5
E
boolean hasNextPage = hasNextPage(currentPage, wl=tN{R
NP>v@jO
totalPage); SH*'<
boolean hasPrePage = hasPrePage(currentPage); ^Z (cVg
/E>;O47a
returnnew Page(hasPrePage, hasNextPage, f5}afPk
everyPage, totalPage, Gz`Jzh
j
currentPage, X)g
X9DA
BRFsw`c
beginIndex); I=`? 4%
} &9jJ\+:7
-:}vf?
privatestaticint getEveryPage(int everyPage){ VPCI5mS_
return everyPage == 0 ? 10 : everyPage; ^}j~:EZb
} ODJ"3 J
N=mvr&arP
privatestaticint getCurrentPage(int currentPage){ f/\!=sa:
return currentPage == 0 ? 1 : currentPage; 8 Ku9;VEk
} N'1I6e"
*0U#Z]t
privatestaticint getBeginIndex(int everyPage, int y"?`MzcJ0
(>`_N%_
currentPage){ 4^(x)r
&(?
return(currentPage - 1) * everyPage; e9acI>^w
} 32GI+NN
s>9I#_4]
privatestaticint getTotalPage(int everyPage, int Vjs2Yenx
K^{j$
totalRecords){ &{)<Q(g
int totalPage = 0; 01Jav~WR
>N3X/8KL%
if(totalRecords % everyPage == 0) EeaJUK]z9
totalPage = totalRecords / everyPage; ,\`ruWWLb=
else / Pjd"
totalPage = totalRecords / everyPage + 1 ; nC:T0OJv
^Ks1[xc* `
return totalPage; @`.4"*@M
} 0+&WIs
DksYKv
privatestaticboolean hasPrePage(int currentPage){ NT6jwK.?)?
return currentPage == 1 ? false : true; sbvP1|P8%
} 97c0bgI!+
jMT[+f
privatestaticboolean hasNextPage(int currentPage, r$<!?Z
-J]?M
int totalPage){ 0GMb?/
return currentPage == totalPage || totalPage == /cS8@)e4
\mF-L,yu
0 ? false : true; <XL%*
} 6 `6I<OJ\
Z@Rqm:e
GEPWb[Oa
} GzEw~JAs
c<13 r=+
kn#?+Q
lh-.I]>&`
Vy&X1lG:
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。 n'rq
?M90K)&g{
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 +kI}O*s
(JU8F-/9
做法如下: (4Db%Iw
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 za>%hZf\
P, x"![6
的信息,和一个结果集List: |E13W
java代码: Jq1oQu|rs
R0M>'V?e
fMwF|;
/*Created on 2005-6-13*/ _d!sSyk`
package com.adt.bo; :7@[=n
tFcQ.1
import java.util.List; |@d(2f8
]n=z(2Z9lD
import org.flyware.util.page.Page; ?`TQ!m6y
II^Rp],>
/** ~U+<JC Z
* @author Joa h`Jc%6o
*/ <mX5VGY9^
publicclass Result { J
rK{MhO
Eq@sU?j
private Page page; R14&V1 tZ
>MJ%6A>
private List content; Gn7\4,C
mq{Z
Q'
/** )t~ad]oM
* The default constructor nANl9;G
*/ 4=MVn
public Result(){ '4{@F~fu
super(); ~vP_c(8f
} A._CCou
+R?E @S
/** x~'_;>]r_
* The constructor using fields u!xgLf'`
* 4][VK/v+
* @param page DN9x<%/-
* @param content !/`AM<`o
*/ r
E1ouz!D
public Result(Page page, List content){ '"Cqq{*
this.page = page; ks$5$,^T2o
this.content = content; wz+mFf
} :WH{wm|
H F*~bL
/** )fXxkOd
* @return Returns the content. 5hqXMs
*/ ko.%@Y(=
publicList getContent(){ `B?+1Gv
return content; @MQfeM-@
} |yNyk7~
y**L^uvr
/** Q3r]T.].h
* @return Returns the page. };2Lrz9<
*/ !}A`6z
public Page getPage(){ 4PC'7V=S
return page; y2k's
} DvN_}h^nX
&2@"zD
/** zt((TD2
* @param content "=s dn
* The content to set. dyqk[$(
*/ ?n<sN"
public void setContent(List content){ w8>lWgN
this.content = content; 7d{xXJ-
} ^`-Hg= d
%jUZc:06
/** E.'6p \
* @param page Gj#BG49g2
* The page to set. )p!")
:'fv
*/ >yyu:dk-;
publicvoid setPage(Page page){ 1>_$O|dE
this.page = page; -8:O?]+Q/
} WbFCj0
} lYS4Q`z$
qq^[(n
823y;
AED
9vDE
j%vxCs>
2. 编写业务逻辑接口,并实现它(UserManager, HVC|0}
11$v~<M
UserManagerImpl) (1,4egMpR
java代码: uxrNkZia
Ux,dj8=o
F&/}x15
/*Created on 2005-7-15*/ p<VW;1bt5
package com.adt.service; 4J[bh
v&^N +>p
import net.sf.hibernate.HibernateException; RplcM%YJn
kSJ:4! lFU
import org.flyware.util.page.Page; X7aj/:fXe
hO3C _}
import com.adt.bo.Result; Y5>'(A>
8BIPEY -I?
/** Xp^>SSt:4
* @author Joa B]D51R\}VE
*/ X bV?=
publicinterface UserManager { -r_ Pp}s
XF4NRs
public Result listUser(Page page)throws RvW>kATb_F
m[5ed1+
HibernateException; lKirc2
UR`pZ.U?
} @[(%b{TE;
HV3D$~g F
wZ8LY;
`Q^Vm3h
B@3>_};Ct
java代码: BW)t2kR&
zHj_q%A
Z}O0DfT;
/*Created on 2005-7-15*/ `O=LQ m`
package com.adt.service.impl; M+Y^ A7
Z*5]qh2r8
import java.util.List; FLlL0Gu
I8hmn@ce
import net.sf.hibernate.HibernateException; *u<@_Oa
"jl`FAu)q
import org.flyware.util.page.Page; 3TD!3p8
import org.flyware.util.page.PageUtil; E<_+Tc
!I8(Y
import com.adt.bo.Result; r,Pu-bhF
import com.adt.dao.UserDAO; Y0OVzp9 b
import com.adt.exception.ObjectNotFoundException; {QLqf
import com.adt.service.UserManager; )3_g&&
HPWjNwM
/** PJcz] <
* @author Joa #`Et{6WS
*/ \=g%W^i
publicclass UserManagerImpl implements UserManager { #lm1"~`5
|Oaj
Jux
private UserDAO userDAO; ]| =#FFz
Xp3cYS*u
/** dv\oVD
* @param userDAO The userDAO to set. d7QQ5FiB
*/ z3}4+~~
publicvoid setUserDAO(UserDAO userDAO){ xZ"kJ'C4}
this.userDAO = userDAO;
t#g6rh&
} 4fzM%ku
Ib4 8`
/* (non-Javadoc) $VJ=A<
* @see com.adt.service.UserManager#listUser >^Z!
ph1veD<ZZ
(org.flyware.util.page.Page) ? Kn~fs8
*/ 0r\hX6 k
public Result listUser(Page page)throws Ol@
YSk d
\+w -{"u$
HibernateException, ObjectNotFoundException { K31rt-IIt
int totalRecords = userDAO.getUserCount(); aKCXV[PO
if(totalRecords == 0) A&0sD}I\K
throw new ObjectNotFoundException Uz!cVs?-
8:A6Ew&\]O
("userNotExist"); mY1$N}8fm
page = PageUtil.createPage(page, totalRecords); - r82'3]
List users = userDAO.getUserByPage(page); ~#~Kxh
returnnew Result(page, users); l>9ZAI\^
} m;LeaD}0
HPj7i;?O
} f&>Q6 {*]
Om2
)$(
L7*~8Y
BT+ws@|[
'x10\Q65[
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 hpym!G
MhB kr{8
询,接下来编写UserDAO的代码: p.1|bXY`
3. UserDAO 和 UserDAOImpl: yHoj:f$$x
java代码: r).S/
Fx0<!_tY-
T3{qn$t8
/*Created on 2005-7-15*/ jX{lo
package com.adt.dao; $wVY)p9Q
c>3W1"
import java.util.List; %P9Zx!i>
@ B3@M
import org.flyware.util.page.Page; .Isg1qrC
: C;=<$
import net.sf.hibernate.HibernateException; ;comL29l2`
W~QZ(:IK
/** +kl@`&ga
* @author Joa R16"lG
*/ T ,gMc
publicinterface UserDAO extends BaseDAO { ]?Ru~N}
bLoYg^T/
publicList getUserByName(String name)throws sM~|}|p
F+AShh
HibernateException; y#Ch /Jg?|
.x1EdfHed/
publicint getUserCount()throws HibernateException; >UuLSF}
uBs[[9je(
publicList getUserByPage(Page page)throws ~GS`@IU}
Px K
HibernateException; te'<xfG
d8
ve$X
} @v2kAOw[
n|L.dBAs]
obX|8hTL%
_&JlE$ua7
Ty]CdyL$
java代码: G#CWl),=
t L;;Yt
7IZ(3B<87t
/*Created on 2005-7-15*/ q^dI!93n|
package com.adt.dao.impl; nS'0i&<{1
w];t ]q|
import java.util.List; iygdX2
/sdkQ{J!.
import org.flyware.util.page.Page; ,)Z^b$H]
Mi'eViH
import net.sf.hibernate.HibernateException; 'J<KL#og
import net.sf.hibernate.Query; 'L0 2lM
<v[,A8Q
import com.adt.dao.UserDAO; y)#Ib*?
M* QqiE
/** kAbT&Rm"
* @author Joa FAU^(]-5m
*/ ;Z.}~d6>!
public class UserDAOImpl extends BaseDAOHibernateImpl P/Sv^d5=e
i' |S
g
implements UserDAO { K#F~$k|1B
.6OE8w
1
/* (non-Javadoc) o~^hsm[44J
* @see com.adt.dao.UserDAO#getUserByName D@4hQC\
CWI(Q`((>
(java.lang.String) P RX:*0
*/ Nc]oAY
publicList getUserByName(String name)throws Yq)
wE|k/
\&AmX8" [
HibernateException { v=SC*
String querySentence = "FROM user in class iQin|$F_O
wTIOCj
com.adt.po.User WHERE user.name=:name"; ";",r^vr\
Query query = getSession().createQuery Fz)z&WT
t_@%4Wn!1L
(querySentence);
{v]A`u)
query.setParameter("name", name); c+|,2e
0T
return query.list(); %qfEFhRC
} >48zRi\N
R0\E?9P
/* (non-Javadoc) Yw+_( 2
9=
* @see com.adt.dao.UserDAO#getUserCount() ;U}lh~e11
*/ t]"3vE>
publicint getUserCount()throws HibernateException { t91v%L
int count = 0; }QG6KJh_%
String querySentence = "SELECT count(*) FROM HHoh//(\
Z:9"7^+
user in class com.adt.po.User"; ZZFa<AK4
Query query = getSession().createQuery W/{HZ< :.
uj;-HN)6
(querySentence); <tgJ-rnL
count = ((Integer)query.iterate().next [al$7R&
4(
^Ht
()).intValue(); (D{9~^EO>a
return count; yHk/8
} )0RH"#,2L
x8gUP
/* (non-Javadoc) ep,kImT
* @see com.adt.dao.UserDAO#getUserByPage H-0A&oG
(?YTQ8QR
(org.flyware.util.page.Page) i+T$&$b
*/ Al'
sY^B
publicList getUserByPage(Page page)throws 0sk*A0HX-
)MW.Y
HibernateException { oXV
String querySentence = "FROM user in class Gv6EJV1i
],&WA?>G
com.adt.po.User"; hq$:62NYg
Query query = getSession().createQuery vQ26U(7\>
qeSxE`E"
(querySentence); Uq0RJ<n
query.setFirstResult(page.getBeginIndex()) >K;p+( <6
.setMaxResults(page.getEveryPage()); 8KT|ixs
return query.list(); m[Px|A5{
} x"5/1b3aq
XrtB&h|C
} }N*6xr*X+
i@Q)`>4
4wMKl6mL
-&D~TL#
"F}anPY
至此,一个完整的分页程序完成。前台的只需要调用 qS|bpC0x
:kflq
userManager.listUser(page)即可得到一个Page对象和结果集对象 70a7}C\/o
^cDHyB=v4d
的综合体,而传入的参数page对象则可以由前台传入,如果用 .0cm
mpUNq
wp-*S}TT
webwork,甚至可以直接在配置文件中指定。 -GDX#A-J
X]tjT
下面给出一个webwork调用示例: _)zSjFX9
java代码: HpuHJ#l
*>9#a0cp
X9#Od9cNaC
/*Created on 2005-6-17*/ 'X"@C;q
package com.adt.action.user; Mfuw y
92bvmP*o4
import java.util.List; 9eH(FB
6|rqsk
import org.apache.commons.logging.Log; 2zh?]if
import org.apache.commons.logging.LogFactory; b,$H!V*
import org.flyware.util.page.Page; #ZRQVC; b;
QOcB ]G
import com.adt.bo.Result; 8@|+-)t
import com.adt.service.UserService; [&j!g
import com.opensymphony.xwork.Action; j#9p0[
ShxB!/s
/** |Ah26<&