Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 f>'Y(dJ'W
+% /s*EC'w
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 0CSv10Tg
Iff9'TE
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 '65LKD
I%|>2}-_U
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 f= >OJ!:
!=;XBd-
。 aA7=q=
W\1i,ew>
分页支持类: f%5zBYCgC
9nu3+.&P
java代码: kq\)MQ"/X
.CP&bJP%
s
{^yj
package com.javaeye.common.util; +_-bJo2a
^Rm
import java.util.List; No2b"G@
t1E[uu ,V8
publicclass PaginationSupport { 6c0>gUQx-
/0\
mx4u
publicfinalstaticint PAGESIZE = 30; 6TP7b|
4Llo`K4
privateint pageSize = PAGESIZE; lKk/p^:
Q)"A-"y
privateList items; a >\vUv*
Ym;*Y !~[
privateint totalCount; cqxVAzb
+r3IN){jz
privateint[] indexes = newint[0]; 8[6o (
y
qtKy
privateint startIndex = 0; o1nURJ!
(8_\^jJ
public PaginationSupport(List items, int h6dPO"
ETs>`#`6o
totalCount){ r$)w7Gk<
setPageSize(PAGESIZE); ">?vir^
setTotalCount(totalCount); <\?wAjc,
setItems(items); h gJ[LU| >
setStartIndex(0); |>@W
]CX[
} G[jW<'f
iQ{G(^sZN
public PaginationSupport(List items, int \"hJCP?,
A!^q
J#
totalCount, int startIndex){ V|\7')Qq
setPageSize(PAGESIZE); qZ@s#UiB
setTotalCount(totalCount); w3jO6*_ M
setItems(items); vq34/c^
setStartIndex(startIndex); r(gXoq_w
} 4&l10fR5
!A48TgAeE
public PaginationSupport(List items, int >:lnt /N3
LR"9D
totalCount, int pageSize, int startIndex){ YuB+k^
setPageSize(pageSize); Ar~"R4!
setTotalCount(totalCount); HaIM#R32T
setItems(items); qWw\_S
setStartIndex(startIndex); sVex
(X
} b86}% FM
JU&+c6>
publicList getItems(){ vm>b m
return items; (h:Rh
} ?6'rBH/w
rj!0GI
publicvoid setItems(List items){ #c2ymQm
this.items = items; R:B^
} qe5feky
J=/5}u_gw
publicint getPageSize(){ (Cqn6dWK
return pageSize; :%IoM E
} irjP>3_e
m# =z7.XrX
publicvoid setPageSize(int pageSize){ $ `7^+8vHV
this.pageSize = pageSize; 7 [0L9\xm
} sJNFFOz
$ MC)}l
publicint getTotalCount(){ GgKEP,O
return totalCount; )p*}e8L
} $tl\UH7%2
F:a ILx
publicvoid setTotalCount(int totalCount){ yr,=.?C-
if(totalCount > 0){ {s;U~!3aY
this.totalCount = totalCount; ElUEteZ
int count = totalCount / 6uR^%W8]
%j7XEh<'
pageSize; @V!r"Bkg.
if(totalCount % pageSize > 0) bV"G~3COy
count++; 5 (A5Y-B
indexes = newint[count]; cph:y
for(int i = 0; i < count; i++){ NFv>B>
indexes = pageSize * ^Ox3XC
0V?F'<qy
i; 8g7<KKw
} -44l^}_u
}else{ =JmT:enV
this.totalCount = 0; {p,]oOq\
} NF?
vg/{
} )+fh-Ui
ZK)%l~J
publicint[] getIndexes(){ #Qkroji
qw
return indexes; fum0>tff
} x#:| }pR
"^Ybs'-
publicvoid setIndexes(int[] indexes){ xMBaVlEN
this.indexes = indexes; -
|gmQG
} LW(6$hpPp
bcupo:N
publicint getStartIndex(){ n93=8;&
return startIndex; 8,uB8C9
} TjG4`:*y#m
aFLO{t r`
publicvoid setStartIndex(int startIndex){ ~ar=PmYV7
if(totalCount <= 0) :<|<|qJWo
this.startIndex = 0; `He,p -
elseif(startIndex >= totalCount) 1x,tu}<u^
this.startIndex = indexes +sJrllrE(
(P`3 @H
[indexes.length - 1]; +U@<\kIF
elseif(startIndex < 0) ZzX~&95G
this.startIndex = 0; D|.ic!w'
else{ twx[s$O'b
this.startIndex = indexes e#k<d-sf6
dh $bfAb
[startIndex / pageSize]; h?pkE
} 3g6j?yYqb
} ()H:Uv M=t
^I+)o1%F
publicint getNextIndex(){ *2GEnAZb7n
int nextIndex = getStartIndex() + +}a ]GTBgA
{*ob_oc
pageSize; BX yo
if(nextIndex >= totalCount) y.q(vzg\_
return getStartIndex(); x+]\1p
else QeK*j/
return nextIndex; @62Mk},9 c
} *Aa?yg:=
!3ctB3eJ
publicint getPreviousIndex(){ %D[0nt|X
int previousIndex = getStartIndex() - 5>TK^1
:
l\n@cQR
pageSize; 9 '2_
if(previousIndex < 0) 2r ZxSg
return0; ivz{L-
else -(b kr+N
return previousIndex; <Z/x,-^*<
} +U3m#Y )k
.e3+s*
} S1?-I_t+]
s@7H1)U
)sT> i
J.|+ID+
抽象业务类 YSe.t_K2C
java代码: 9tqF8pb7v
_x5 3g
A
tq|hPd<C
/** ~T89_L
* Created on 2005-7-12 mN19WQ(r
*/ 6!(@@^7{*
package com.javaeye.common.business; Q0ON9gqqv
,zT y?OQ
import java.io.Serializable; (zFi$
import java.util.List; VZl6t;cn
+) m_o"hl
import org.hibernate.Criteria; .?hP7;hhI
import org.hibernate.HibernateException; 1&U>,;]*
import org.hibernate.Session; cx0*X*
import org.hibernate.criterion.DetachedCriteria; BGu?<bET
import org.hibernate.criterion.Projections; a 7,C>%I
import j ku}QM^
g"> {9YE
org.springframework.orm.hibernate3.HibernateCallback; `FC(
import Kc^;vT>3
*C:|X b<9
org.springframework.orm.hibernate3.support.HibernateDaoS +PuPO9jKO@
c7FRI0X
upport; 0a "c2J
TU
1I} ,
import com.javaeye.common.util.PaginationSupport; lgtC |kM=
` 5C~
public abstract class AbstractManager extends D= h)&
O7 $hYk
HibernateDaoSupport { ~7Tc$
"I
m
RO~aD!N
privateboolean cacheQueries = false; x
a06i#
(#E.`e1#6
privateString queryCacheRegion; 4tS.G
=>! Y{:
y(
publicvoid setCacheQueries(boolean '^"6+ k
X.e7A/ClEo
cacheQueries){ 5>\/[I/!
this.cacheQueries = cacheQueries; BV[ 5}
} w&KK3*=""
X<%Q"2hW
publicvoid setQueryCacheRegion(String mFZ?hOyP.
]V#M%0:Q82
queryCacheRegion){ {b
this.queryCacheRegion = ~Wa6J4B{K
_n` a`2C|m
queryCacheRegion; UZpIcj cL
} <N9[?g)
5x>}O3Q_
publicvoid save(finalObject entity){ gE?|_x#
getHibernateTemplate().save(entity); !!? Mw
} BFOq8}fX2
jE/AA!DC#
publicvoid persist(finalObject entity){ '4#}e[e
getHibernateTemplate().save(entity); jYhB
+|
} jWE:ek*
"UJ
S5[7$
publicvoid update(finalObject entity){ & J2M1z%
getHibernateTemplate().update(entity); cu/5$m?xx
} 9BuSN*4
/Dj=iBO
publicvoid delete(finalObject entity){ 8!Ww J
Oe
getHibernateTemplate().delete(entity); 7F{3*`/6
} '5|h)Q5
`p;I}
publicObject load(finalClass entity, 9Q+'n$s0^
la+[bm<v
finalSerializable id){ 9AJ7h9L
return getHibernateTemplate().load XnWr5-;
N/K.%<h
(entity, id); wLOB}ZMT
} 9^G/8<^^>
[+DW >Et
publicObject get(finalClass entity, <U\B!fO'
gY8>6'~mS
finalSerializable id){ @("a.;1#o
return getHibernateTemplate().get p$3sME$L
_ "VkGG
(entity, id); hK,Sf ;5V
} pxh"B\"4*
L=sYLC6d
publicList findAll(finalClass entity){ Nu?-0>
return getHibernateTemplate().find("from AGYc |;
7*Ej. HK
" + entity.getName()); j+,d^!
} +y3%3EKs1~
YS *9t
Q{
publicList findByNamedQuery(finalString -3=#u_
?qWfup\S
namedQuery){ W|g4z7Pb
return getHibernateTemplate 7M<'/s
bKN@j'M
().findByNamedQuery(namedQuery); <yH4HY
} J.xPv)1'
$NZ-{dY{
publicList findByNamedQuery(finalString query, zp%Cr.)$
c5D)
finalObject parameter){ "$N+"3I
return getHibernateTemplate Gf<'WQ[
.w8J*JZ
().findByNamedQuery(query, parameter); r 0iK
} wlqpn(XR
esMX-.8Cx
publicList findByNamedQuery(finalString query, 283F)T\Rv
SX#
e:_
finalObject[] parameters){ `u
teg=
return getHibernateTemplate R&BTA
tAv@R&W,
().findByNamedQuery(query, parameters); e(GP^oK
} 9E"vN
Ke2ccN
publicList find(finalString query){ [VsKa\9u
return getHibernateTemplate().find HTS%^<u
V#S9H!hm$
(query); \(^nSy&N
} m;GbLncA
8)10o,#L
publicList find(finalString query, finalObject a@UZb
<?riU\-]y
parameter){ ='s(|
return getHibernateTemplate().find [nrYpb4
G?;e-OhV
(query, parameter); f-`)^5E
} yEhTNBa*h{
:<bB?N(
public PaginationSupport findPageByCriteria rzm:Yx
4O )1uF;
(final DetachedCriteria detachedCriteria){ n O\"HLM
return findPageByCriteria 0dGAP
%B5wH_p
(detachedCriteria, PaginationSupport.PAGESIZE, 0); }:KEj_~.
} zGAq-<
_0]S69lp
public PaginationSupport findPageByCriteria #AL=f'2=f
AK*LyR?
(final DetachedCriteria detachedCriteria, finalint t>`asL
R |(q
startIndex){ I uMQ9&
return findPageByCriteria Tk:h@F|B.|
`\#B18eU
(detachedCriteria, PaginationSupport.PAGESIZE, `OXpU,Z 6U
j/f?"VEr
startIndex); [d1mLJAR
} hPUYyjXPB
"NXB$a!:
public PaginationSupport findPageByCriteria y)W@{@{kl
%'s>QF]'
(final DetachedCriteria detachedCriteria, finalint D*gFV{Ws
=E.t`x=
pageSize, 117EZg]O
finalint startIndex){ 4,CXJ2
return(PaginationSupport) }dWq=)*
o7sT=x9
getHibernateTemplate().execute(new HibernateCallback(){ ToXki,
publicObject doInHibernate MbZJ;,e?
V@cM |(
(Session session)throws HibernateException { 7b;I+q
Criteria criteria = _/6!yyl
zxbpEJzpn
detachedCriteria.getExecutableCriteria(session); 8&?s#5zA
int totalCount = i]6`LqlO
hRrn$BdLX
((Integer) criteria.setProjection(Projections.rowCount XINu=N(g
ZjQ
|Wx
()).uniqueResult()).intValue(); s'E2P[:
criteria.setProjection JGsx_V1t
2.l Z:VLN
(null); ^Eb.:}!D6
List items = %_RQx2
D#il*
criteria.setFirstResult(startIndex).setMaxResults /H(?
2IHC
cDFO; Dr
(pageSize).list(); si`A:14R
PaginationSupport ps = 52 fA/sx
Crho=RJPR
new PaginationSupport(items, totalCount, pageSize, ZniB]k1
-QM:
q
startIndex); JORGj0v
return ps; aB{vFTD5
} )z73-M V"
}, true); j53*E
)d
} h_:C+)13`x
vq^f}id
public List findAllByCriteria(final 5_I->-<
;#xmQi'`
DetachedCriteria detachedCriteria){ 4'`{H@]tb
return(List) getHibernateTemplate 6K-_pg]
'=nQ$/!q
().execute(new HibernateCallback(){ % NA9{<I
publicObject doInHibernate fPn>v)lN{
5NS[dQG5
(Session session)throws HibernateException { %r%M lj:#
Criteria criteria = =vDEfO/T
Rs-]N1V
detachedCriteria.getExecutableCriteria(session); 86 W9rR
return criteria.list(); F)&@P-9+
} aY'C%^h]
}, true); ]iN'x?Fo
} #{?PbBE}
P9^-6;'Y
public int getCountByCriteria(final >/kcdWl
uxtWybv
DetachedCriteria detachedCriteria){ Q[vJqkgT
Integer count = (Integer) wRcAX%n&
CFzNwgv]z
getHibernateTemplate().execute(new HibernateCallback(){ \Xm,OE_v"
publicObject doInHibernate WQ[_hg|k
"?ucO4d
(Session session)throws HibernateException { q>$ev)W
Criteria criteria = DnCP
aM4%
iYORu3
detachedCriteria.getExecutableCriteria(session); Tl$[4heE
return L;VoJf
Co (.:z~
criteria.setProjection(Projections.rowCount iop2L51eJ
C([phT;
()).uniqueResult(); Vr6@>@SC
} S1p;nK
}, true); cC=[Saatsf
return count.intValue(); 3 Nreqq
} 42e|LUZg
} WG6FQAo^8
W-x?:X<}
\
e\?I9
{QcLu"?c
gVq;m>\|F
4L ;% h
用户在web层构造查询条件detachedCriteria,和可选的 WHsgjvh"
tBq
nfv
startIndex,调用业务bean的相应findByCriteria方法,返回一个 pm*xb]8y
#MX'^RZ>2
PaginationSupport的实例ps。 =|M>l
o<<xY<
ps.getItems()得到已分页好的结果集 1rv)&tKs
ps.getIndexes()得到分页索引的数组 ])|d"[ur=
ps.getTotalCount()得到总结果数 //T>G_1
ps.getStartIndex()当前分页索引 M9V
q
-U18
ps.getNextIndex()下一页索引 rR9|6l
3
ps.getPreviousIndex()上一页索引 mef<=5t
[5zx17'
T&%ux=Jt
Kqp(%8mf
G;v8$)Zj
#33fGmd[
jhXkSj
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Q<h-FW8z
yaah*1ip[
,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 8P^ITL z%
Rv#]I#O
一下代码重构了。 E~%jX
}/
1Ty<\bZ=
我把原本我的做法也提供出来供大家讨论吧: |B'9\OkP[=
xIxn"^'
首先,为了实现分页查询,我封装了一个Page类: sm0x LZ
java代码: 5b!vgm#])
-~v|Rt
uJFdbBDSh
/*Created on 2005-4-14*/ fBRo_CU8!
package org.flyware.util.page; 4]h
=yc R
$
et0s;GBv
/** J)`-+}7$v
* @author Joa f|h|q_<;
* :n0vQ5a
*/ h\5OrD@L
publicclass Page { ln?v
j)j
;'5>q&[qbP
/** imply if the page has previous page */ (d(hR0HKE
privateboolean hasPrePage; AvdXEY(-
7![,Q~Fy
/** imply if the page has next page */ M,/mE~
privateboolean hasNextPage; 3&u&x(
\@8+U;d
/** the number of every page */ z.GMqW%B
privateint everyPage; K8>zF/# +
BybW)+~
/** the total page number */ 85n1eE
privateint totalPage; .QA }u ,EN
tNGp\~
/** the number of current page */ |?qquD 4=
privateint currentPage; 62 O.?Ij
7B!xT2{T
/** the begin index of the records by the current k"NVV$;
DE%KW:Hug
query */ ~-EOjX(X'E
privateint beginIndex; ]z l[H7
9cf:pXMi
@!`Xl*l
/** The default constructor */ }dp=?AFg
public Page(){ 2.% .Z_k)
^C_#<m_k
} ppZDGpp
{$R' WXVs
/** construct the page by everyPage IB[)TZ2m
* @param everyPage i'9vL:3
* */ ~~v3p>z Rr
public Page(int everyPage){ ?Lyxw]
this.everyPage = everyPage; :?/cPg'D
} 8-BflejX
gW-V=LV (
/** The whole constructor */ ft$RSb#
public Page(boolean hasPrePage, boolean hasNextPage, a"FCZ.O1
BReJ!|{m}
4:|S` jm
int everyPage, int totalPage, D@Vt^_
int currentPage, int beginIndex){ kuol rfGB
this.hasPrePage = hasPrePage; ;?8_G%va
this.hasNextPage = hasNextPage; tS|(K=$
this.everyPage = everyPage; fjU8gV
this.totalPage = totalPage; $lLz3YS
this.currentPage = currentPage; 'R
c,Mq'
this.beginIndex = beginIndex; lEhk'/~
} R $&o*K`?
K Pt5=a
/** byTh/ H
* @return Olh<,p+x
* Returns the beginIndex. /4g1zrU
*/ l y(>8F
publicint getBeginIndex(){ o| #Qu8Lk
return beginIndex; c
)G3k/T5
} 4WJ.^ (
cFeXpj?GV
/**
yls
^ cyX
* @param beginIndex v#.r.{t
* The beginIndex to set. '=Rs/EDME
*/ z"0I>gl
publicvoid setBeginIndex(int beginIndex){ 8Le||)y,\
this.beginIndex = beginIndex; (>r[-Bft
} <-[wd.M_
pov)Z):}G<
/** gLy&esJl1
* @return m06ALD_
* Returns the currentPage. {buo^kgj`]
*/ B)qWtMZx
publicint getCurrentPage(){ k&,~qoU
return currentPage; Q
aS\(_
} rNB_W.
B oC5E#;G
/** W3 'q\+
* @param currentPage P/Q!<I
* The currentPage to set. LN@F+CyDc
*/ i'#E)
publicvoid setCurrentPage(int currentPage){ ~zJ?H<>
this.currentPage = currentPage; Ib+Y~
XYR
} V+VkY3
4<k9?)~(J
/** /+@p7FqlE
* @return }Q=!Y>Tc
* Returns the everyPage. e A#;AQm
*/ T3k#VNH
publicint getEveryPage(){ vvKEv/pN7
return everyPage; A1.7O
} zmSUw}-4N
_Em.
/** {=F/C,-
* @param everyPage pKit~A,Q
* The everyPage to set. bT^I"
*/ %?p1d!
publicvoid setEveryPage(int everyPage){ ~v6OsH%vx
this.everyPage = everyPage; =Ur}~w&H8
} aB7+Tb
][?G/*k
/** qI~xlW
* @return Tl2C^j
* Returns the hasNextPage. @wE5S6! B\
*/ (X?%^^e!
publicboolean getHasNextPage(){ 4}4Pyjh
return hasNextPage; A29gz:F(
} &NH$nY.r
m]5Cq6
/** F.w5S!5Q
* @param hasNextPage .HkL2m
* The hasNextPage to set. ?TU }~}
*/ t.`@{R$hoA
publicvoid setHasNextPage(boolean hasNextPage){ 9J9)AV
this.hasNextPage = hasNextPage; fjs
[f'L
} f"qga/
iZaI_\"__
/** !f&Kf,#b`
* @return :=wTvz
* Returns the hasPrePage. N4L|;?
*/ a hR ^
publicboolean getHasPrePage(){ =jX8.K4]
return hasPrePage; 2JJ"O|Ibz
} L1Iz<>
}>VG~u8
/** ,PWgH$+
* @param hasPrePage v"OY 1<8
* The hasPrePage to set. XgLL!5`
*/ gG-BVl"59
publicvoid setHasPrePage(boolean hasPrePage){ 1@QZnF5[
this.hasPrePage = hasPrePage; /+\uqF8F
} dt`{!lts'
V&Xe!S
/** -3;*K4z$/
* @return Returns the totalPage. n#wI@W>%+
* .zn;:M#T
*/ Db;G@#x
publicint getTotalPage(){ YRh BRE
return totalPage; Y6Lf@}2(i
} ]8f ms(
+(C6#R<LI
/** B,TB3
{
* @param totalPage WXmn1^"kK}
* The totalPage to set. vfq%H(
*/ ds?v'|
publicvoid setTotalPage(int totalPage){ lJE93rXU
this.totalPage = totalPage; 59O?_F9
} WIv?}gi:
X
=y/8^^
} i1>-QDYnJ
\9/ b!A
Lz:(6`S
{ Fawt:
~wJFa'2
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 IGtl\b=
.h>8@5/s
个PageUtil,负责对Page对象进行构造: IuNiEtKx
java代码: r9
!Tug*>m
+TQ47Zc
hA33K #bC
/*Created on 2005-4-14*/ *g[^.Sg
package org.flyware.util.page; /Rg*~Ers
*
)w0AC"2O~
import org.apache.commons.logging.Log; > 3&: 5
import org.apache.commons.logging.LogFactory; o9F/y=.r=
K00
87}H
/** s;64N'HH
* @author Joa /C4^<k\
* -eN\ !
*/ \U[{z&]~
publicclass PageUtil { T)Y=zIQ1]7
hNd}Y'%V
privatestaticfinal Log logger = LogFactory.getLog lhw()u
wAxrc+
(PageUtil.class); /6h(6 *JI
<oo
/** '*?WU_L(g
* Use the origin page to create a new page &9"-`-[e:
* @param page }b0; 0j
* @param totalRecords <_XWWT%
* @return 9\]^|?zQ`
*/ yq NzdzX
publicstatic Page createPage(Page page, int Wh%ucX&
T+<A`k: -
totalRecords){ `/~8}Y{
return createPage(page.getEveryPage(), -tyK~aasQ
ngat0'oa
page.getCurrentPage(), totalRecords); /l<<_uk$
} 1$81E.
V2i@.@$j
/** _<NMyRJo
* the basic page utils not including exception W~p/,H cM
aOiR l,
handler tc!wLnhG
* @param everyPage m/qbRk68s
* @param currentPage YJl("MZ
* @param totalRecords 61jI
* @return page [fKUyIY_
*/ !V,{_(LT
publicstatic Page createPage(int everyPage, int {FG|\nPw
EoxQ
*/
currentPage, int totalRecords){ e&qh9mlE
everyPage = getEveryPage(everyPage); ^4`Px/&
currentPage = getCurrentPage(currentPage); =@8H"&y`
int beginIndex = getBeginIndex(everyPage, * C6a?]
i![dPM
currentPage); (>I`{9x>6
int totalPage = getTotalPage(everyPage, l+g9 5mjP
pTyi!:g3W
totalRecords); 3Bx:Ntx<
boolean hasNextPage = hasNextPage(currentPage, !ZI7&r`u;
;x8k[p~2
totalPage); T7d9ChU\#.
boolean hasPrePage = hasPrePage(currentPage); &2=dNREJ}1
K.z64/H:
returnnew Page(hasPrePage, hasNextPage, ]Wq?H-B{
everyPage, totalPage, \;mH(-
currentPage, !k/Pv\j/R
Kbb78S30
beginIndex); !\,kZ|#>
} e4z1`YLsG
+5&wOgx
privatestaticint getEveryPage(int everyPage){ -M1YE
return everyPage == 0 ? 10 : everyPage; P7x =
} H_ez'yy
,+
#6Y_
privatestaticint getCurrentPage(int currentPage){ }A:<%N
return currentPage == 0 ? 1 : currentPage; \C`~S7jC
} ?&^?-S% p
a
/:@"&Y
privatestaticint getBeginIndex(int everyPage, int bgK<pi)d
|-CnT:|o
currentPage){ "/nNM{^
return(currentPage - 1) * everyPage; !E-Pa5s
} 3^Q]j^e4Ny
UD)e:G[Gat
privatestaticint getTotalPage(int everyPage, int PGARXw+
^_%kE%I
totalRecords){ j*
*s^Sg
int totalPage = 0; vUnRi=:|
!QT'L,_
if(totalRecords % everyPage == 0) 2"d!(J6}K
totalPage = totalRecords / everyPage; u]ZqOJXxu
else KV*xApb9y
totalPage = totalRecords / everyPage + 1 ; }irn'`I
bC3 F
return totalPage; 4ON_$FUe
} @5[kcU>
]Y| 9?9d
privatestaticboolean hasPrePage(int currentPage){ s #S%#LM
return currentPage == 1 ? false : true; vc]cNz:mQ
} Y&^ P"Dw
1<h>B:
privatestaticboolean hasNextPage(int currentPage, Vm|Y$C
{"
4e+y
int totalPage){ ad_`x
return currentPage == totalPage || totalPage == 2]c{P\
j}AFE
0 ? false : true; bLnrbid
} c. A|Ir
&BvZF
[*Z`Kc
} gn{=%`[
@Kgl%[NmX
7lo|dg80
QERU5|.wc
F>X-w+b4r
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。 "sgjWo6
P/ oXDI8
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 tWdhDt8$&
Fbp{,V@F2
做法如下: 07/L}b`P
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >2?aZ`r+
ZK'-U,Y.H7
的信息,和一个结果集List: 0iZGPe~
java代码: ~kCwJ<E
&
``d
l6u&5[C
/*Created on 2005-6-13*/ _NcYI
package com.adt.bo; m"9XT)N
WpLZQ6wH
import java.util.List; [,aqQ6S
JNFIT;L
import org.flyware.util.page.Page; BvU"4d;x
P &)1Rka
/** -OYDe@Wb]
* @author Joa nCKbgM'"
*/ gs
W0
publicclass Result { YUdxG/~'
NA.1QQ;e
private Page page; 6UE(f@
CZEW-PIhj
private List content; CVi`bO 4\
Ce'pis
/** 3},Zlu
* The default constructor sK 2
e&
*/ 9%IlW
public Result(){ Q#Y k?Kv~
super(); jb /8?7
} 4{qB X?
i\H+X
/** XTDE53Js&
* The constructor using fields 60Z]M+8y8
* ?Mp1~{8
* @param page E&B{5/rv
* @param content to6;?uC+|i
*/ z\/53Sy<
public Result(Page page, List content){ 6TH!vuQ1(
this.page = page; .]|Zf!>}s
this.content = content; QI_59f>
} C#w]4 $/
ofW+_DKB?l
/** &)pK%SAM
* @return Returns the content. fB+b}aoV
*/ ap}5ElMR
publicList getContent(){ YGsS4ia*4i
return content; m/`IGT5J
} fRm}S>Nibb
p[WX'M0f
/** y>\S@I
* @return Returns the page. ;:mY JV
*/ M)cGz$Q|
public Page getPage(){ /dDzZ%/@
return page; E-1"+p
} ^UA(HthY
Iwpbf Z
/** Qeb}!k2A
* @param content xiyxrR;
* The content to set. \O7J=6fn
*/ XV'fW~j\
public void setContent(List content){ 89cVJ4]g~!
this.content = content; !~lW3
} l>v{
JLb6C52
/** x:t<ZG&Xwg
* @param page Ewo*yY>
* The page to set. (3*UPZv
*/ &2EBk= X
publicvoid setPage(Page page){ yoqa@ V
this.page = page; ODf4+& u
} *(cU]NUH_
} YYRT.U'
!ax;5 @J
^t'3rft
&k
T"oK
F3ZxhkF
2. 编写业务逻辑接口,并实现它(UserManager, J -Qh/d%]
i9UI,b%X
UserManagerImpl) LNQSb4
java代码: !k~z5z'=py
?kt=z4h9(
jnoL2JR[=-
/*Created on 2005-7-15*/ 30FykNh
package com.adt.service; ~_ !ts{[E
&WZP2Q|
import net.sf.hibernate.HibernateException; MY-.t-3
a%hGZCI
import org.flyware.util.page.Page; @XOi62(
G+)?^QTn
import com.adt.bo.Result; YDiN^q7
-O&"|
/** z^sST
* @author Joa ,m07p~,V
*/ S 2$5!(P
publicinterface UserManager { .#^0pv!
dDKqq(9(`
public Result listUser(Page page)throws F,G,b
Fc0jQ@4=
HibernateException; pH9HK
h'^FrWaU/
} ZHy><=2
?gV'(3
!
!=[uT+v
7tH]*T9e>
CKTrZxR"
java代码: qmmv7==
Q?;C4n4]l
L2Ux9_S
/*Created on 2005-7-15*/ 9y"TDo
package com.adt.service.impl; p
q-!WQ
lSc,AOXp
import java.util.List; |l90g|isJ
/BzA(Ic/
import net.sf.hibernate.HibernateException; (Cj,\r
6MrKi|'X@
import org.flyware.util.page.Page; sT<{SmBF
import org.flyware.util.page.PageUtil; E_[ONm=,
R @r{
import com.adt.bo.Result; g'G8 3F
import com.adt.dao.UserDAO; 3kLOoL?
import com.adt.exception.ObjectNotFoundException; Kp_jy.e7&
import com.adt.service.UserManager; }(=ml7 )v
GqjO>v fy
/** ZBj6KqfST%
* @author Joa 7b.U!Ju
*/ `=!p$hg($
publicclass UserManagerImpl implements UserManager { J1-):3A
rh $1-Y
private UserDAO userDAO; \ j]~>9
v+tO$QZ`
/** ^\YQ_/\~L
* @param userDAO The userDAO to set. 3%NE/lw1
*/ K<,Y^3]6?
publicvoid setUserDAO(UserDAO userDAO){ N&B>#:
this.userDAO = userDAO; Cnur"?w@o
} hCLk#_
TczXHT}G
/* (non-Javadoc) GUCM4jVT^
* @see com.adt.service.UserManager#listUser mcMb*?]
A*Q[k 9B
(org.flyware.util.page.Page)
-HT L5
*/ zjoo{IH}
public Result listUser(Page page)throws ,#%SK;1<
#5d8?n
HibernateException, ObjectNotFoundException { a97Csxf;7
int totalRecords = userDAO.getUserCount(); ^@ UjQ9[>
if(totalRecords == 0) <t6d)mJ%
throw new ObjectNotFoundException m9g^ -X
=n
}Yqny
("userNotExist"); f)tc 4iV
page = PageUtil.createPage(page, totalRecords); ~\bHfiIDy
List users = userDAO.getUserByPage(page); Fhi5LhWe+.
returnnew Result(page, users); `Y\QUj
} 1OPfRDn.bk
8g5.7{ky
} !'PlDGD
~D!ESe*=
8XkIk7
Qy%xL9
*08+\ed"#
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 j}RM.C\7
akrCs&Kka5
询,接下来编写UserDAO的代码: hE5G!@1F
3. UserDAO 和 UserDAOImpl: 3d U#Ueu
java代码: 5|m9:Hv[#
J]]\&MtaO
#x|VfN5f
/*Created on 2005-7-15*/ >;.*
package com.adt.dao; MZiF];OY
|bvGYsn_#=
import java.util.List; W["HDR
WV~SL/k|
import org.flyware.util.page.Page; HtS#_y%(
M[vCpa
import net.sf.hibernate.HibernateException; _pW'n=}R
@_uFX!;
/** V"U~Q=`K
* @author Joa `NoCH[$!+
*/ I9:%@g]uYw
publicinterface UserDAO extends BaseDAO { j>g9\i0O1
+9}' s{
publicList getUserByName(String name)throws 0, "ZV}
JSUzEAKe
HibernateException; 2?pM5n
R''Sfz>8
publicint getUserCount()throws HibernateException; ;>'SV~F
(aBP|rxg
publicList getUserByPage(Page page)throws 'iDu0LX
(T;1q^j
HibernateException; SFOQM*H
'U*udkn 2]
} ?xf~!D
kz|[*%10
)rS^F<C
2PI #ie4
b__n~\q_
java代码: PKATw>zg<
~CJYQFt
cxk=|
?l
/*Created on 2005-7-15*/ "vvFq ,c
package com.adt.dao.impl; s~#?9vW
!zl/0o
import java.util.List; "9.6\Y\*
~v,!n/('
import org.flyware.util.page.Page; E'fX&[
@)06\h
import net.sf.hibernate.HibernateException; Q,O]x#
import net.sf.hibernate.Query; <6gU2@1
ir"* iL=
import com.adt.dao.UserDAO; =I{S;md
uJ7,rq
/** :nTkg[49pJ
* @author Joa )8\Z=uC
*/ C=M?
public class UserDAOImpl extends BaseDAOHibernateImpl FJ nG<5Rh
MEDskvBG
implements UserDAO { AZ}%MA;q
/}[zA@
/* (non-Javadoc) ..]B9M.
* @see com.adt.dao.UserDAO#getUserByName c
'/2F0y
oF`-cyj"
(java.lang.String)
8APTk
*/ Q&tFv;1w6
publicList getUserByName(String name)throws baA HP"
>hh"IfIZ4
HibernateException { 9eksCxFg
String querySentence = "FROM user in class 7Ljs4>%l9j
chM t5L+5
com.adt.po.User WHERE user.name=:name"; `<bCq\+`
Query query = getSession().createQuery =] 6_{#Z<
D_]i/
F%
(querySentence); vs*_;vx
query.setParameter("name", name); A/r;;S)%2
return query.list(); F&-5&'6G+
} %_cg|yy
b49|4
/* (non-Javadoc) &xF4p,7
* @see com.adt.dao.UserDAO#getUserCount() %pQdq[J={
*/ V:$[~)k8
publicint getUserCount()throws HibernateException { t"4Rn<-
int count = 0; 8'>.#vyMGv
String querySentence = "SELECT count(*) FROM eo-XqiJ,]
u_$6LEp-
user in class com.adt.po.User"; t%ou1&SO
Query query = getSession().createQuery W"#j7p`d
'Sm/t/g"|
(querySentence); *T1L)Cp
count = ((Integer)query.iterate().next 9$}+-Z
axt6u)4%7:
()).intValue(); WllCcD1
return count; Zm?G'06
} JT}dor
OqUE4.vIP
/* (non-Javadoc) :z}~U3,JE
* @see com.adt.dao.UserDAO#getUserByPage K.c6Rg
Fvcq^uZ
(org.flyware.util.page.Page) >V77X+!
*/ ,5%aP%
publicList getUserByPage(Page page)throws U*c{:K-C
jFK9?cLT
HibernateException { uT@8 _9
String querySentence = "FROM user in class xQcMQ{&;
!dYX2!lvT
com.adt.po.User"; p2M?pV
Query query = getSession().createQuery .XZ 71E
\3
O-}n1S
(querySentence); y^vfgP<@
query.setFirstResult(page.getBeginIndex()) S<)RVm,!e
.setMaxResults(page.getEveryPage()); $]`'Mi
return query.list(); ~%::r_hQ
} :5n"N5Go
INeWi= 1
} 4l#T_y
SvCK;$:
w2RESpi
9^=t@
M?:f^
至此,一个完整的分页程序完成。前台的只需要调用 vs)HbQ
(>kBmK1Aj
userManager.listUser(page)即可得到一个Page对象和结果集对象 3w6J V+?
`"1{Sx.
的综合体,而传入的参数page对象则可以由前台传入,如果用 S(YHwH":
xw/h~:NT
webwork,甚至可以直接在配置文件中指定。 UOOR0$4
+5seT}h
下面给出一个webwork调用示例: MWp\D#H
java代码: Mf,Mcvs
h1D~AgZOVj
*]DJAF]
/*Created on 2005-6-17*/ XJV3oj
package com.adt.action.user; <y b=!
HtS1N}@
import java.util.List; rVIb'sa
/s-jR]#VA
import org.apache.commons.logging.Log; cnjj)
c
import org.apache.commons.logging.LogFactory; t8wz'[z
import org.flyware.util.page.Page; -;DE&~p
"|~B};|MFF
import com.adt.bo.Result; EZa{C}NQ$2
import com.adt.service.UserService; QL|:(QM
import com.opensymphony.xwork.Action; ?geWR_Z
{?kKpMNNn
/** :@z5& h
* @author Joa *X=f
*/ \?Oly171
publicclass ListUser implementsAction{ _tR.RAaa"
4jZi62
privatestaticfinal Log logger = LogFactory.getLog jd*%.FDi{
PxCl]~v
(ListUser.class); M,v@G$pW
4<K ,w{I
private UserService userService; LMhY"/hAXa
j#.-MfB
private Page page; Duo#WtC
FZ'>LZ
privateList users; PY3Vu]zD
\c@qtIc
/* cq+M
*1;
* (non-Javadoc) sD8xH
* sou$qKoG01
* @see com.opensymphony.xwork.Action#execute() \?`d=n=
*/ ,BN}H-W\2
publicString execute()throwsException{ 9"u@<]
Result result = userService.listUser(page); C`K9WJOD
page = result.getPage(); qjRiTIp9q
users = result.getContent(); :4L5@>b-
return SUCCESS; ztxQv5=:,
} =B 4g EWR
VAB&&AL
/** h"Yqm"U/
* @return Returns the page. 0m|
Gp
*/ xuH<=-O>ki
public Page getPage(){ gQcr'[[a
return page; Qak@~b
} F|3FvxA
z$im4'\c
/** TB3T:A>2
* @return Returns the users. g)G7
kB/<p
*/ SO jDtZ
publicList getUsers(){ HjY-b*B
return users; 7g<`wLAH
} {XUfxNDf
xo"4mbTV
/** 0b QiUcg/
* @param page 06W=(fY
* The page to set. YKS'#F2
*/ y&I|m
publicvoid setPage(Page page){ igbb=@QBJ
this.page = page; p<nBS"/
} .j4ziRa-
]j#$. $q
/** Z
5YW L4s
* @param users 8`*9jr
* The users to set. %D6Wlf+^n
*/ 9P>S[=
publicvoid setUsers(List users){ OL9C#er
this.users = users; =$z$VbBv
} s&_O2(l
7JwWM2N?V
/** S2GBX1
* @param userService ?g*T3S"
* The userService to set. HyYQQ
*/ i3WmD@
publicvoid setUserService(UserService userService){ u2\qg;dP
this.userService = userService; Fea\ eB
} \ A UtGP
} c\rbLr}l)
5pyvs ;As
<T% hfW
uV:uXQni``
7[<sl35
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, &,kB7r"
I;4CvoT
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 9}Ave:X^
{3uSg)
么只需要: Wjk;"_"gd
java代码: !P^$g
R
1? hd
oK1[_ko|
<?xml version="1.0"?> i|noYo_Ah\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork -&$%m)wN
R;,HtN
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Gqc6).tn
H+&w