Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Rap =&
'Im&&uSkr
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Epm%/ {sHV
&B@qb?UE1
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 G&\!!i|IQ
$E35W=~)
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 ;Ebpf J
&^JYIRn1\
。 VCCG_K9'
yiAusl;
分页支持类: Zoyo:vv&
jx-8%dxtZ
java代码: N,?D<NjXl
dY$jg
*rmwTD"
package com.javaeye.common.util; U\`yLsKvH`
q,fk@GI'2
import java.util.List; x5YHmvy/l
kOLS<>.
publicclass PaginationSupport { qp`G5bw
.9u,54t
publicfinalstaticint PAGESIZE = 30; a4D4*=!G0
2\L}Ka|v
privateint pageSize = PAGESIZE; hZDv5]V:0
O/{W:hJjd
privateList items; ~\~XD+jy"
*h Bo,
privateint totalCount; d
A' h7D
L}.V`v{zc
privateint[] indexes = newint[0]; :taRCh5
#7dM %
privateint startIndex = 0; JrVBd hLr
fH[:S9@
public PaginationSupport(List items, int !|;w(/
M$AQZ')9
totalCount){ ko<VB#pOMr
setPageSize(PAGESIZE); d){Al(/
setTotalCount(totalCount); GcA!I!j/
setItems(items); a&~]77)
setStartIndex(0); )`gE-udR
} #^;^_
Q=cbHDB
public PaginationSupport(List items, int WA 79(B
5jBBk*/\
totalCount, int startIndex){ _=oNQ
setPageSize(PAGESIZE); Gj(UA1~1
setTotalCount(totalCount); n:5*Tg9
setItems(items); zV=(e( [
setStartIndex(startIndex); 6P:H`
} ;3k6_ub
G9uWn%5r
public PaginationSupport(List items, int `Ao;xOJ
8L}N,6gC4_
totalCount, int pageSize, int startIndex){ Zjh9jvsW
setPageSize(pageSize); ?FRQ!R
setTotalCount(totalCount); fl18x;^I
setItems(items); R@H}n3,
setStartIndex(startIndex); BlvNBB1^
} !WReThq
h8uDs|O9n
publicList getItems(){ u:7=Yy
:
return items; DUK.-|a7
} ;q&\>u:
vXi}B
publicvoid setItems(List items){ ds9`AiCW>
this.items = items; 3`aJ"qQE
} 59I}
Bt^];DjH
publicint getPageSize(){ `[J(au$z
return pageSize; #O.-/&Z
} b1{XGK'
.cX,"2;n
publicvoid setPageSize(int pageSize){ lZupn?
this.pageSize = pageSize; AFcA5:ja
} E~|`Q6&Y
i|Y_X
publicint getTotalCount(){ =7Y gES
return totalCount; 4$+9k;m'
} n! (g<"
Q,A`"e#:
publicvoid setTotalCount(int totalCount){ iAlFgOk'
if(totalCount > 0){ @9rmm)TZ
this.totalCount = totalCount; NX*9nwp^
int count = totalCount / V-(LHv
8@a|~\3-
pageSize; m'%Z53&
if(totalCount % pageSize > 0) r6-'p0|
count++; OWK)4[HY(
indexes = newint[count]; \T_?<t,UT
for(int i = 0; i < count; i++){ ?JD\pYg[/
indexes = pageSize * IJn r^S8
J}.y+b>8\
i; fV.43E
} 6)eU &5z1?
}else{ }PY?
ZG
this.totalCount = 0; aUy=D:\
} h;KI2k_^
} {&c%VVZb:Z
V8xv@G{;
publicint[] getIndexes(){ 1% )M-io
return indexes; 'c<@SVF{Zz
} #:68}f"$
:;XHA8
publicvoid setIndexes(int[] indexes){ 7=ZB;(`L1
this.indexes = indexes; xUD$i?3z
} (;T;?v`-
1LjYV
publicint getStartIndex(){ ;6 1m
return startIndex; lC1X9Op
} vN7ihe[C
o+O\VNW
publicvoid setStartIndex(int startIndex){ 8[FC
if(totalCount <= 0) FK#>E[[
this.startIndex = 0; lm&C!{K
elseif(startIndex >= totalCount) ~::gLm+f
this.startIndex = indexes =k[!p'~jD
*0R=(Gy
[indexes.length - 1]; QLH
s 3eM
elseif(startIndex < 0) ii*Ty!Sa
this.startIndex = 0; i
c]f o
else{ 5hp b=2
this.startIndex = indexes j>s%q.
,7M9f
[startIndex / pageSize]; C_#0Y_O
} F
,{nG[PL
} 3@}HdLmN|
%'* |N[
publicint getNextIndex(){ YS{
int nextIndex = getStartIndex() + ,oP-:q!PC
2+GF:[$
pageSize; 3a{QkVeV7
if(nextIndex >= totalCount) hP,1;`[1
return getStartIndex(); wrn[q{dX
else ?k_=?m
return nextIndex; "eQ9 6^'J
} !*|CIxk(
y::;e#.
publicint getPreviousIndex(){ ~9oS~fP?I
int previousIndex = getStartIndex() - =QyO$:t
#OWwg`AWv
pageSize; ~ilbW|s?=k
if(previousIndex < 0) B>Nxc@=D
return0; `s:| 4;.
else .(S,dG0P
return previousIndex; /p>"|z
} 6XQ)Q)
66'TdF]"
} }C#YR(]
6w}:w?=6
MO#%w
m2|0<P@k!
抽象业务类 !gf&l ^)
java代码: JpDYB
5Cy)#Z{
]NAPvw#p
/** X\%],"9%
* Created on 2005-7-12 {b<8Z*4W
*/ )X^nzhZ2O"
package com.javaeye.common.business; XY4s
+]]wf'w
import java.io.Serializable; g'Xl>q
import java.util.List; 7FDraEr#f
T>uLqd{hH
import org.hibernate.Criteria; F'j:\F6C;
import org.hibernate.HibernateException; )edM@beY_
import org.hibernate.Session; Z=F=@ <!
import org.hibernate.criterion.DetachedCriteria; Wt3\&.n
import org.hibernate.criterion.Projections; 6!"15dPN
import N M8F
Z@ws,f^e
org.springframework.orm.hibernate3.HibernateCallback; ?|hzAF"U
import e#'`I^8l
,Fr{i1Ky
org.springframework.orm.hibernate3.support.HibernateDaoS -~(0:@o ;
u8<=FV3
upport; x:2[E-
9i`LOl:;
import com.javaeye.common.util.PaginationSupport; tIr66'8
d ,QJf\fc"
public abstract class AbstractManager extends ]owH [wvX
A:NY:#uC
HibernateDaoSupport { >Le
mTr
Dea;9O
privateboolean cacheQueries = false; F'#3wCzt
Q49|,ou[H
privateString queryCacheRegion; [#Yyw8V#<
vl*RRoJ
publicvoid setCacheQueries(boolean ;OKQP~^iH2
,Xh4(Gn#b
cacheQueries){ .M!
(|KE4
this.cacheQueries = cacheQueries; i5n'f6C
} QHM39Eu]
@P.l8|w
publicvoid setQueryCacheRegion(String }]s~L9_z['
*TXq/
3g
queryCacheRegion){ Xl aNR+
this.queryCacheRegion = ]52_p[hZ}<
.Nf*Yqs0
queryCacheRegion; +'Ge?(E4_
} <K0lS;@K
k{bba=<
publicvoid save(finalObject entity){ q/3}8BJ
getHibernateTemplate().save(entity); 8EE7mEmLH
} 3Q ]MT
Yr31GJ}K
publicvoid persist(finalObject entity){ SUVr&S6Nk
getHibernateTemplate().save(entity); & aLR'*]6
} OKU P
SA&wW\Ym]
publicvoid update(finalObject entity){ n)=&=Uj`f
getHibernateTemplate().update(entity); \ D[BRE+
} Qxvz}r.l]
QAJ>93
publicvoid delete(finalObject entity){ @KpzxcEoO
getHibernateTemplate().delete(entity); l1:j/[B=
} /.?\P#9)
DuE>KX{<!R
publicObject load(finalClass entity, )3
r1; ^W
d}=p-s.GA
finalSerializable id){ zm}1~A
return getHibernateTemplate().load evs2dz<eA
-( iJ<
(entity, id); p>zE/Pw~
} g<C})84y3
z]WT>4
publicObject get(finalClass entity, + mcN6/
2
g8PU$T
finalSerializable id){ 0I _;?i
return getHibernateTemplate().get wLO/2V}/
/0c&!OP
(entity, id); _NkN3f5 1L
} 4J_%quxO
Rk=B;
publicList findAll(finalClass entity){ z%KChU
return getHibernateTemplate().find("from qb<gh D=j
H xlw1(zS
" + entity.getName()); 1,QRfckks
} Xm4wuX"e=
QXz!1o+"
publicList findByNamedQuery(finalString S&Sf}uK
m\>x_:sE
namedQuery){ h>/ViB@"W|
return getHibernateTemplate vuZ<'?Nm
L~$RF {$
().findByNamedQuery(namedQuery); 1=X=jPwO C
} G](K2=
mOB\ `&h5
publicList findByNamedQuery(finalString query, Lv4=-mWv&0
bDo'hDmW
finalObject parameter){ _"bx#B*
return getHibernateTemplate J53;w:O
}:mI6zsNj
().findByNamedQuery(query, parameter); c`.:"i"k3
} r &[~/m8zl
la4,Z
publicList findByNamedQuery(finalString query, HA%ye"(y8
Esjv^* v9-
finalObject[] parameters){ M($},xAvDU
return getHibernateTemplate >
95Cs`>d
(`NRF6'&1L
().findByNamedQuery(query, parameters); P Cf|^X#B
} wl%1B64
NIfc/%
publicList find(finalString query){ #dft-23
return getHibernateTemplate().find =<05PB
_:L*{=N
(query); K)?^b|D
} xD=D *W
rYJ))@
publicList find(finalString query, finalObject R}>Do=hAO
,gvX ~k
parameter){ !D3}5A1,
return getHibernateTemplate().find W!k6qTz)
}D^Gt)
(query, parameter); #+;=ijyF
} taQ[>x7b
6`C27
public PaginationSupport findPageByCriteria 7|-xM>L$A
DX";v
J
(final DetachedCriteria detachedCriteria){ zEW:Xe)
return findPageByCriteria K*9b `%
=;H'~
(detachedCriteria, PaginationSupport.PAGESIZE, 0);
%\cC]<>
} 4Le5Ms/
Z|c9%.,
public PaginationSupport findPageByCriteria Lvq]SzOw
dx}/#jMa
(final DetachedCriteria detachedCriteria, finalint ry
?2 o!
~@8d[Tb
startIndex){ Yg[IEy
return findPageByCriteria S nHAY<
l5[xJH
(detachedCriteria, PaginationSupport.PAGESIZE, m_2P{
!r*;R\!n2
startIndex); M9#QS`G
} p|d9g
^
=!^iiHF
public PaginationSupport findPageByCriteria [,^dM:E/
3ms/v:\
(final DetachedCriteria detachedCriteria, finalint CD_f[u
7]%il[
pageSize, (;&?B.<\:
finalint startIndex){ yU"G|Ex
return(PaginationSupport) Ij1]GZ`A(
G)hH?_U#T
getHibernateTemplate().execute(new HibernateCallback(){ p2vBj. *J
publicObject doInHibernate jtv Q<4
pT@!O}'$
(Session session)throws HibernateException { \&5@ yh
Criteria criteria = nZCpT
|M5
xbC8Amo;8"
detachedCriteria.getExecutableCriteria(session); UD2<!a'T
int totalCount = +^?-}v
2g6_qsqi
((Integer) criteria.setProjection(Projections.rowCount //lZmyP?
Iv72;ZCh?6
()).uniqueResult()).intValue(); 41o!2(e$
criteria.setProjection ,6O9#1A&i
@/~k8M/
(null); e6HlOGPVQH
List items = tR*W-%
_]UDmn[C
criteria.setFirstResult(startIndex).setMaxResults 9*;isMkq<
;j U-<
(pageSize).list(); 6 ]PM!6
PaginationSupport ps = m5w9l"U]H
9K46>_TyH
new PaginationSupport(items, totalCount, pageSize, Czr4
-#2
MLBg_<
startIndex); kA%OF*%|6
return ps; .k`*$1?73x
} s2?,' es
}, true); `B\KS*Gya#
} : .o=F`W
=jIT"rk
public List findAllByCriteria(final V`,[=u?c
n>:c}QAJH
DetachedCriteria detachedCriteria){ 8EG8!,\I
return(List) getHibernateTemplate Cw[Od"B\?U
#A/J^Ko
().execute(new HibernateCallback(){ tH,K\v`f
publicObject doInHibernate ~,!hE&LE~
yp{F8V 8
(Session session)throws HibernateException { UD<^r]'x
Criteria criteria = v?D
kDnta
W(a'^
#xe
detachedCriteria.getExecutableCriteria(session); ZqbM%(=z(`
return criteria.list(); 1mn$Rh&dO
} C}=_8N
}, true); h2|vB+W-
} 9U9c"'g
V,XP&,no\j
public int getCountByCriteria(final Z#Zzi5<
4zqE?$HM'
DetachedCriteria detachedCriteria){ \kV7NA
Integer count = (Integer) uP{+?#a_-\
P}+|`>L
getHibernateTemplate().execute(new HibernateCallback(){ qa$[L@h>
publicObject doInHibernate 7tl)4A6
k]$E8[.t
(Session session)throws HibernateException { 9hR:y.
Criteria criteria = K~Au?\{
im\YL<
detachedCriteria.getExecutableCriteria(session); I0l.KiBm
return '5xuT _
Ec*--]j*c
criteria.setProjection(Projections.rowCount $qlqWy-s
p=-B~:
()).uniqueResult(); ?%dCU~ z
} bpF@}#fT
}, true); |T$a+lHMD
return count.intValue(); eW"x%|/Q7
} }`9fZK{. @
} ~e`;"n@4
{7TJgS
>b4YbLkI#
$: 4mOl
=>:% n
C`)^~C_]`3
用户在web层构造查询条件detachedCriteria,和可选的 N
t>HztXd
P96Cw~<Q?
startIndex,调用业务bean的相应findByCriteria方法,返回一个 `z$uw
v;bM.OL
PaginationSupport的实例ps。 D)*_{
a(x.{}uG,
ps.getItems()得到已分页好的结果集 yo?g"vbE
ps.getIndexes()得到分页索引的数组 &Qtp"#{
ps.getTotalCount()得到总结果数 f=_Bx2ub
ps.getStartIndex()当前分页索引 b#Fk>j
ps.getNextIndex()下一页索引 M=\d_O#;Z
ps.getPreviousIndex()上一页索引 A|
gs Uh
!8
wid&
SA`J.4yn
} `>J6y9
,WO%L~db
t7*G91Hoq&
mq{$9@3
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 )WP]{ W)r
>uyeI&z
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 c69U1
s=q%:uCO
一下代码重构了。 sxN>+v11z
c?p0#3%L#
我把原本我的做法也提供出来供大家讨论吧: 4[5lX C
u,Q_WR-wJ
首先,为了实现分页查询,我封装了一个Page类: nj~$%vmA
java代码: pu2 wEQ
,);=
(r9
u-%r~ }
/*Created on 2005-4-14*/ f\x@ C)E
package org.flyware.util.page; _o &,
P;L)1 g
/** XDP6T"h
* @author Joa r|\5'ZMx
* %67G]?EXB
*/ r{R[[]p
publicclass Page { w!B,kqTG
)T.pjl
/** imply if the page has previous page */ VeNNsg>&
privateboolean hasPrePage; fXF=F,!t
Xa{~a3Wy
/** imply if the page has next page */ =9DhO7I'
privateboolean hasNextPage; uS:
A4tN
?;:9
W
/** the number of every page */
8(vC jL
privateint everyPage; 7GBZA=J
d5w_[=9U
/** the total page number */ DqurHQ z)m
privateint totalPage; Ad}-I%Ie
;I!+lx3[
/** the number of current page */ R
(tiIo
privateint currentPage; :c~9>GCE&
PSP1>-7)w
/** the begin index of the records by the current fB;&n
wc6
E-rB
query */ +X* F<6mZ
privateint beginIndex; ' D)1ka.
K)Df}fVOc
CU#L *kz
/** The default constructor */ eHVdZ'%x
public Page(){ r!=]Q}`F
;1{iF2jZ:
} %Lh-aP{[e
Vr&el
/** construct the page by everyPage RR[)UQ
* @param everyPage i$`|Y*
* */ P;)2*:--)
public Page(int everyPage){ >~`Y
this.everyPage = everyPage; _SMT.lG
} }"%!(rx
di]$dl|Wi
/** The whole constructor */ rt5oRf:wY
public Page(boolean hasPrePage, boolean hasNextPage, ql{^"8x
=R8f)UQYx
(ZE%tbm2
int everyPage, int totalPage, CbTf"pl
int currentPage, int beginIndex){ Qag|nLoT
this.hasPrePage = hasPrePage; ;x!,g5q"q
this.hasNextPage = hasNextPage; Z-4K?;g'k
this.everyPage = everyPage; X;s3y{ku
this.totalPage = totalPage; t/v@vJ`vSH
this.currentPage = currentPage; pX>ua5Z
this.beginIndex = beginIndex; 7%:??*"~
} Qq`3S>
NDB*BmG
/** "?oo\op
* @return ?dp-}3/G
* Returns the beginIndex. %-h7Z3YcN
*/ x\Nhix}1D
publicint getBeginIndex(){ D 7Gd%
return beginIndex; f0-RhR
} &q," !:L]
>QYh}Z-/%
/** r\A@&5#q
* @param beginIndex kbfuvJ>
* The beginIndex to set. 89*S?C1
*/ bh= \
publicvoid setBeginIndex(int beginIndex){ J>f
/u:.
this.beginIndex = beginIndex; 3q'K5}
_
} +O|_P`HBoI
t!6\7Vm/
/** gzl%5`DB w
* @return ^z[_U}N\}
* Returns the currentPage. q1N4X7<_
*/ sl~b\j
publicint getCurrentPage(){ =1gDjF9|
return currentPage; ^K7q<X ,
} keT?,YI
/- DKV~
/** C#A@)>
* @param currentPage )v${&H
* The currentPage to set. &tlR~?$e*
*/ B*9
publicvoid setCurrentPage(int currentPage){ fswZM\@
this.currentPage = currentPage; Eem 2qKj
} M.o?CX'
,$HHaoog
/** ,3G$`
* @return UqD5
A~w
* Returns the everyPage. fdd~e52f
*/ NY~ dM\
publicint getEveryPage(){ "F&Tnhh4
return everyPage; LTg?5GwD\j
} \ua9thOG
*Zc9yZl2
/** Rb{+Ki
* @param everyPage 5/Ydv
RB67
* The everyPage to set. 4qqF v?O[r
*/ x2sN\tOh^
publicvoid setEveryPage(int everyPage){ s ;48v
this.everyPage = everyPage; eA`]KalH
} ?2H{^\<(e
613/K`o
/** {]+ jL1
* @return TAXd,z N
* Returns the hasNextPage. F?!FD>L{`
*/ `ffj8U
publicboolean getHasNextPage(){ Z$Z`@&U=
return hasNextPage; 2}D,df'W4
} ].LJt['%8
CoKiQUW
/** Us1@\|]
* @param hasNextPage !.9l4@z#
* The hasNextPage to set. 5r'=O2AZX
*/ A$/KP\0Y2
publicvoid setHasNextPage(boolean hasNextPage){ ]a8eDy
this.hasNextPage = hasNextPage; g* %bzfk=|
} Y3D3.T6Q
1oB$MQoc
/** |p;4dL
* @return fwRGT|":B
* Returns the hasPrePage. 0rV/qMo;K
*/ *^n^nnCwp
publicboolean getHasPrePage(){ :RPVT,O}
return hasPrePage; ZmNZS0j
} AzZi{Q ?
pMOD\J:l,
/** N[>:@h
* @param hasPrePage 3QH(4N
* The hasPrePage to set. _\p`4-.V
*/ /#29Y^Z)=
publicvoid setHasPrePage(boolean hasPrePage){
wtlB
this.hasPrePage = hasPrePage; H1Q''$}Z.
} Mk<m6E$L
IT,"8s
/** QDP-E[
* @return Returns the totalPage. SzRL}}I
* 2%bhW,?I
*/ S<*' ;{5~
publicint getTotalPage(){ '=$TyiU
return totalPage; MdLj,1_T
} tAaYL
\~
e "_&z#
2_
/** /\~l1.6`
* @param totalPage ^<!Ia
* The totalPage to set. #&k8TY
*/ gEE9/\>%-
publicvoid setTotalPage(int totalPage){ ;
/=L
this.totalPage = totalPage; u]R$]&<
} T{ok +$w2
av$
} nz>K{(
) 9xX
V):`&@
f;R>Pr;rD
fD0{ 5
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 .6LS+[
Sq<3Rw
个PageUtil,负责对Page对象进行构造: :r\xkHg/f
java代码: So?m?,!W
"8FSA`>=
y`({ .L
/*Created on 2005-4-14*/ }N@n{bu+
package org.flyware.util.page; TWtC-wI;
3=IG#6)~C
import org.apache.commons.logging.Log; $%B5$+
import org.apache.commons.logging.LogFactory; _n7%df
h:_NA
/** FbmsN)mv!%
* @author Joa u9BjgK(M
* f0OgK<.>T
*/ 'w:bs!
publicclass PageUtil { CNq[4T'~A
3XnE y
+
privatestaticfinal Log logger = LogFactory.getLog # 9V'';:
RTZ:U@
(PageUtil.class); Q~8y4=|#CY
hc"6u\>
/** &eU3(F`.
* Use the origin page to create a new page f
P+QxOz
* @param page `6UtxJSx
* @param totalRecords W5|j1He&
* @return
C[R`Ml
*/ +eC3?B8rN
publicstatic Page createPage(Page page, int uC)Zs, _5
zqY)dk
totalRecords){ ]uAS+shQ&
return createPage(page.getEveryPage(), (NPxab8e*
@FU~1u3d
page.getCurrentPage(), totalRecords); CPVmF$A-
} #sS9vv7i
/;7ID41
/** ]?M)NRk%S
* the basic page utils not including exception .5]{M\aA
4'` C1 a
handler X'jr|s^s
* @param everyPage _%;M9Sg3
* @param currentPage 3h LqAj
* @param totalRecords 72u db^
* @return page :1*zr
*/ 9Eu #lV
publicstatic Page createPage(int everyPage, int sLZ>v
8sH50jeP
currentPage, int totalRecords){ B O]=vH
everyPage = getEveryPage(everyPage); v"/TmiZ
currentPage = getCurrentPage(currentPage); l!/!?^8|f
int beginIndex = getBeginIndex(everyPage, >GmN~"iJ
QTfu: m{
currentPage);
RvR:e|
int totalPage = getTotalPage(everyPage, >2u y
lf6|.
totalRecords); XO%~6Us^
boolean hasNextPage = hasNextPage(currentPage, loBtd%wY
TH YVT%v
totalPage); [t$4Tdd
boolean hasPrePage = hasPrePage(currentPage); ,&[7u9@
CB6 o$U
returnnew Page(hasPrePage, hasNextPage, _!%M%
everyPage, totalPage, *Er? C;
currentPage, ]H>+m
9
h mds(lv7
beginIndex); yZ5x88 >
} }f]b't
M}u1qXa
privatestaticint getEveryPage(int everyPage){ f0u56I9
return everyPage == 0 ? 10 : everyPage; 4
A5t*e
} 1TIlINlJ
F(;jM(
privatestaticint getCurrentPage(int currentPage){ Fh^ox"3c
return currentPage == 0 ? 1 : currentPage; nGns}\!7'
} GyuV
%
8?kP*tmcZ
privatestaticint getBeginIndex(int everyPage, int j3{HkcjJG
mTJ"l(,3
currentPage){ jFG5)t<D
return(currentPage - 1) * everyPage; aLYLd/ KV
} 'g~@"9'oe
Y<aO
privatestaticint getTotalPage(int everyPage, int o)p[
C
gJK KR]4*
totalRecords){ HS7_MGU
int totalPage = 0; ^&-a/'D$,
(_U^
if(totalRecords % everyPage == 0) -,|ha>r
totalPage = totalRecords / everyPage; VVFV8T4
else jWSb5#Pw
totalPage = totalRecords / everyPage + 1 ; |Q5+l.%
K\aAM;)-
return totalPage; JN|VPvjE
} q1w|'V
,z[(k"
privatestaticboolean hasPrePage(int currentPage){ t$5jx
return currentPage == 1 ? false : true; ZtR&wk
} Za0gs @$
St2Q7K5s{
privatestaticboolean hasNextPage(int currentPage, 0E1=W6UZ
~{P:sjsU
int totalPage){ vtZ?X';wh
return currentPage == totalPage || totalPage == >D~w}z/fk
1AT'S;`
0 ? false : true; pqH4w(;
} "$DldHC
c|Y!c!9F
R^6Zafp
} {-h, ZdH^
fnWsm4
S/fW/W*/}
CL1
oAk
MJ\r 4n
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 +sRP<as
&XtRLtgS
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 8%-%AWF]
Hd374U<8]T
做法如下: BGzO!s*@j
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 hlC%HA
]-a{IWVN
的信息,和一个结果集List: FT(iX`YQ
java代码: ZV(
w
l&Q!mU}
wV:C<Mg7q
/*Created on 2005-6-13*/ jtCZfFD?
package com.adt.bo; `kPc!I7Y
wVE:X3Ei
import java.util.List; M~p=#V1D
(Q_2ODKo
import org.flyware.util.page.Page; K$ AB} Fvc
1`QsW&9=b
/** lQL:3U0DjU
* @author Joa Ihqs%;V
*/ c
D7FfJ
publicclass Result { fv2=B)8$
4.'JLArw
private Page page; GS4_jvD-
C_Gzv'C"L
private List content; e9:P9Di(b
!F$R+A+L
/** ^yJ:+m;6K
* The default constructor vI|As+`$d
*/ ESv:1o`?n
public Result(){ L/fRF"V
super(); 7wi%j!
} Q;wB{vr$
'F7VM?HBfg
/** %t[K36,p
* The constructor using fields )$_,?*fq:
* )*D'csGc
* @param page +v-LL*fa
* @param content M _ (2sq
*/ k!owl+a
public Result(Page page, List content){ ;{Jb6'K1h
this.page = page; ^mf jn-=3
this.content = content; <[<247%
} y
1nU{Sc@
xqv[?
?
/** .Q[yD<)Ubs
* @return Returns the content. F.
T@)7
*/ a:}E& ,&M
publicList getContent(){ ?wCs&tM
return content; |[LE9Lq/
} jyQVSQs
K(OaW)j
/** Y 1y E
* @return Returns the page. l#xw.2bo
*/ Xm@aYNV
public Page getPage(){ }N]!0Ka
return page; g_M^E-3
} ~6HDW
e8q4O|I_
/** >3P9 i ;W
* @param content Noz&noq
* The content to set. }NwN2xTB
*/ $eX*
public void setContent(List content){ s5AgsMq
this.content = content; iC*U $+JG
} O^NP0E
WK4@:k
m6)
/** \O? u*
* @param page > UWStzH<
* The page to set. ZAeQ~ j~
*/ <T4(H[9B
publicvoid setPage(Page page){ a.,i.2
this.page = page; G=cNzr9
} OoM_q/oI
} c[:Wf<%|
t:T?7-XIE
Nb1J ~v
oyW00]ka
&^+3errO
2. 编写业务逻辑接口,并实现它(UserManager, u`6/I#q`
L|J~9FM
UserManagerImpl) 9wMEvX70
java代码: EneAX&SG
MA6P"?
@\PpA9ebg%
/*Created on 2005-7-15*/
qpTm
package com.adt.service; W_m!@T"@H
MS{{R+&
import net.sf.hibernate.HibernateException; 74]a/'4
@d)LRw.I
import org.flyware.util.page.Page; ohsH 2]C
qiU5{}
import com.adt.bo.Result; :k N5?t=
d$[8w/5Of
/** BSDk9Oc
* @author Joa 7E\gxQ(vU
*/ WgPgG0VJE
publicinterface UserManager { ytz8=\p_b
(#z;(EN0t
public Result listUser(Page page)throws ^#w{/C/n
}4vjKSV
HibernateException; =GTD"*vwr
_[JkJwPTx
} ;
8E;
G_+Ph^
.[,6JU%
6|oWaA\gI
}{mG/(LX8
java代码: n^Vxi;F
ymkR!
o8tS
/*Created on 2005-7-15*/ 0[9I0YBJ
package com.adt.service.impl; Mr.JLW
L$}g3{
import java.util.List; LU(%K{9
M')bHB(~v
import net.sf.hibernate.HibernateException; I%i:)6Un-y
j6og3.H-
import org.flyware.util.page.Page; PY-+ Bf
import org.flyware.util.page.PageUtil; A8!Ed$@
H
pFb{
import com.adt.bo.Result;
0Ve%.k
import com.adt.dao.UserDAO; MHl^/e@
import com.adt.exception.ObjectNotFoundException; eE9|F/-L
import com.adt.service.UserManager; 6F-JK1i
9`INC~h
/** z5 pc3:
* @author Joa ~<eVl
l=
*/ oAnigu;
publicclass UserManagerImpl implements UserManager { K7Gm-=%
y1u9B;Fd
private UserDAO userDAO; ?@3&dk~ni
zp#:EZ
/** 5%&]
* @param userDAO The userDAO to set. H!. ZH(asY
*/ #s{aulx
publicvoid setUserDAO(UserDAO userDAO){ pw;r 25
this.userDAO = userDAO; f8#*mQ
} $`v+4]
:ol6%Z's
/* (non-Javadoc) )Oe`s(O@[I
* @see com.adt.service.UserManager#listUser N33AcV!*8
UM`nq;>
(org.flyware.util.page.Page) .HCaXFW
*/ R=Ymo.zs6
public Result listUser(Page page)throws 5v3RVaqZ
O8[k_0@
HibernateException, ObjectNotFoundException { 6y9C@5p}B
int totalRecords = userDAO.getUserCount(); u?Z
<n:
if(totalRecords == 0) `I{ tZ$iD
throw new ObjectNotFoundException ?U JSxL
?~ ?Hdv
("userNotExist"); {wv&t R;
page = PageUtil.createPage(page, totalRecords); n.I2$._(b
List users = userDAO.getUserByPage(page); ?$16A+
returnnew Result(page, users); `[bJYZBc2
} (Z
8,e
lvx]jd\
} c>rKgx
{=6)SBjf
x,f>X;04
Mlwdha0
!3?yG
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 +0dT^Jkqg
.OV-`TNWj
询,接下来编写UserDAO的代码: ,m3":{G:t.
3. UserDAO 和 UserDAOImpl: mZE8.`
java代码: w#<p^CS
egWx9xX
I8Kb{[?q
/*Created on 2005-7-15*/ Bi
XTC$Oi
package com.adt.dao; M=6G:HHY
sNf
+ lga0
import java.util.List; >+SZd7p
>"b[r
import org.flyware.util.page.Page; 8(^
,r#Gy
u6pIdt
import net.sf.hibernate.HibernateException; c(CJ{>F%
?y46o2b*)
/** ZBC@xM&-
* @author Joa 6: GN(R$0
*/ /vy?L\`)#
publicinterface UserDAO extends BaseDAO { Mn{XVXY@qm
R~c IT:i
publicList getUserByName(String name)throws p&uCp7]U
a-:pJE.'p
HibernateException; 716hpj#*
OiF ]_"
publicint getUserCount()throws HibernateException; RJLFj
A-;^~I
publicList getUserByPage(Page page)throws ^F&A6{9f/h
3@'lIV
?,q
HibernateException; ^1Yo-T(R
uD[^K1Ag]^
} 0H<4+
*`K
Z7oaQ\fR
@f%wd2
)lOji7&e
=nw0# '
java代码: u
X>PefR
Q~b_dx{m
boIVU`F-!
/*Created on 2005-7-15*/ d _uFY:
package com.adt.dao.impl; g*28L[Q~
}`#Bf
import java.util.List; t+J)dr
zG<0CZQ8
import org.flyware.util.page.Page; "!^c
'cYQ?;
import net.sf.hibernate.HibernateException; ze
?CoDx2
import net.sf.hibernate.Query; tbY SK
=:;YTie
import com.adt.dao.UserDAO; RpjSTV8Tkm
pb6 Q?QG,
/** Z+Xc1W^
* @author Joa dhs#D:/{9
*/ K# /Ch5?
public class UserDAOImpl extends BaseDAOHibernateImpl dw3'T4TC?
bYK]G+Ww
implements UserDAO { hg{ &Y(J!U
@
E >eq.m
/* (non-Javadoc) 0T=jR{j!o
* @see com.adt.dao.UserDAO#getUserByName uV!MW= )
W!y)Ho
(java.lang.String) GgT=t)}wu
*/ 48;~bVr}
publicList getUserByName(String name)throws Na-q%ru
~yd%~|
HibernateException { W;91H'`?H
String querySentence = "FROM user in class ynx WQ%d(`
?$2q P`-
com.adt.po.User WHERE user.name=:name"; I51M}b,[d
Query query = getSession().createQuery FU'^n6[<B
q;KshpfRMD
(querySentence); 0:s8o@}
query.setParameter("name", name); g:;Ya?5N
return query.list(); !\3}R25
} Qf"6PJ
= >P_mPP=
/* (non-Javadoc) 5 =*@l
* @see com.adt.dao.UserDAO#getUserCount() )\(lg*?:
*/ ~T;K-9R
publicint getUserCount()throws HibernateException { X4XFu
int count = 0; e
W9)@nVJ
String querySentence = "SELECT count(*) FROM ~>4@;
E*h0#m|)
user in class com.adt.po.User"; bU:V%B?=]
Query query = getSession().createQuery Z"4VHrA
p_A5C?&
(querySentence); 4{g:^?1=
count = ((Integer)query.iterate().next %+D-y+hn
9t.fij
()).intValue(); Wn2Ny jX
return count; "^18&>^
} 5f/@:~
x_]",2 W'
/* (non-Javadoc) |:dCVd<du
* @see com.adt.dao.UserDAO#getUserByPage \YjB+[.
sb8z_3
(org.flyware.util.page.Page) FfZ{%E
*/ XryQ)x(
publicList getUserByPage(Page page)throws u=1B^V,6V
5?D1][
HibernateException { q#l.A?rK\
String querySentence = "FROM user in class =ZFcxGo
f2BS[$oV4
com.adt.po.User"; 2Zv,K- G
Query query = getSession().createQuery Mr#oT?
ScM}m
(querySentence); O_qu;Dx!
query.setFirstResult(page.getBeginIndex()) XCKY
xv&
.setMaxResults(page.getEveryPage()); 5?<|3
return query.list();
h4J{j h.
} FZM
]o
V]+o)A$
} ?3.(Vqwog
^A:!ni@3
*2w_oKE'+5
eUzU]6h
&C
CHxjsKR
至此,一个完整的分页程序完成。前台的只需要调用 L3-<Kop
1v>
userManager.listUser(page)即可得到一个Page对象和结果集对象 WHZe)|n
Q=)"om
的综合体,而传入的参数page对象则可以由前台传入,如果用 e);bF>.~
K7)j
webwork,甚至可以直接在配置文件中指定。 ,Zf
:R
Y*]l|)a6_]
下面给出一个webwork调用示例: MoC*tImWR
java代码: >u'/$k
>#Grf)@"6
dqIZ#;:g
/*Created on 2005-6-17*/ D}=/w+
package com.adt.action.user; |JirBz
j+z'
import java.util.List; AAeQ- nbP
Dx p>
import org.apache.commons.logging.Log; }rFsU\]:q
import org.apache.commons.logging.LogFactory;
w0q?\qEX
import org.flyware.util.page.Page; KZ367&>b7
I{i:B
import com.adt.bo.Result; yfRUTG
import com.adt.service.UserService; 03i?"MvNo
import com.opensymphony.xwork.Action; 6Cop#kW#
n"K {uj))
/** ==PQ-Ia
* @author Joa +ZD[[+
*/ Eg287B
publicclass ListUser implementsAction{ E.5*Jr=J
!#cKF6%
privatestaticfinal Log logger = LogFactory.getLog 4OqE.LFu
a PcGI
(ListUser.class); {9m!UlTtw
~@)-qV^~
private UserService userService; 0ECO/EuCg
n $D}0wSM/
private Page page; XL"v21X
Bd N{[2
privateList users; sWojQ-8}
Wo1V$[`Dy
/* F3H:I"4
* (non-Javadoc) P?WT)C2)u
* $=@9 D,R
* @see com.opensymphony.xwork.Action#execute() 7(nz<z p
*/ <