Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 gn"_()8cT
;B>2oq
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 | W:JI
fdP[{.$?(
据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 YOo?.[}@
!Ziq^o.
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 \NwL #bQ~
mle"!*
。 ?'uxYeX6
N6H/J_:
分页支持类: NFTEp0eP
:9!?${4R
java代码: 0]3%BgZ(a8
Hp;Dp!PLa
Uv'.]#H<
package com.javaeye.common.util; GWa_^
"QA <5P
import java.util.List; u(V4KUk
sxcpWSGA^
publicclass PaginationSupport { oZ;u>MeZ
?z>ZsD
publicfinalstaticint PAGESIZE = 30; $FUWB6M
AG6tt
privateint pageSize = PAGESIZE; ~L
j[xP
A7@5lHMF
privateList items; FRpTYLA2
hp?hb-4l
privateint totalCount; ;i|V++$_
6Ouy%]0$I3
privateint[] indexes = newint[0]; TGx:#x*k
|pk1pV |
privateint startIndex = 0; odAeBQy
QU0K'4Yx5j
public PaginationSupport(List items, int 6+HpN"?e
KrN#>do&<
totalCount){ X]d["
setPageSize(PAGESIZE); l%@>)%LA
setTotalCount(totalCount); >(+g:p
setItems(items); g@]G
[(
setStartIndex(0); +4U ?*:n
} fnV^&`BB
xe5|pBT
public PaginationSupport(List items, int !X721lNP
g|_-O"l
totalCount, int startIndex){ Kj;gxYD>6
setPageSize(PAGESIZE); $8#zPJR&
setTotalCount(totalCount); z;`o>Ja2
setItems(items); {~7VA
setStartIndex(startIndex); xFcJyjo^z
} S;[g0j
i_8q!CL@{
public PaginationSupport(List items, int A9^t$Ii
8*yhx
totalCount, int pageSize, int startIndex){ _:F0>=$
setPageSize(pageSize); Nq
%@(K
setTotalCount(totalCount); Ym
IVtQ
setItems(items); XUeBK/aQ{
setStartIndex(startIndex); g}nlb.b]{m
} iDej{95
xKIzEN
&
publicList getItems(){ "F%w{bf
return items; _hlLM,p
} @#[<5ld
tpp. 9
publicvoid setItems(List items){ P wL]v. :
this.items = items; *cn,[
} ],{b&\
*k$&U3=
publicint getPageSize(){ R<aF;Rvb5
return pageSize; ]H8,}
} j8kax/*[
MzLnD D^
publicvoid setPageSize(int pageSize){ W]cJP
this.pageSize = pageSize; lrg3n[y-l
} ?.66B9Lld
p%A
s6.
publicint getTotalCount(){ Zhb)n
return totalCount; F8{"Rk}
} :[f2iZ"
wRu+:<o^.
publicvoid setTotalCount(int totalCount){ R5=2EwrGP
if(totalCount > 0){ A?I/[zkc
this.totalCount = totalCount; ,YzrqVY
int count = totalCount / )`5kfj
R B7?T5G
pageSize; 92g#QZs&W
if(totalCount % pageSize > 0) ?g*#ld()
count++; /y/O&`X(
indexes = newint[count]; .|x\6
jf
for(int i = 0; i < count; i++){ )i@j``P
indexes = pageSize * F&?&8.
=8BMCedH|
i; $S{B{FK
} /7Z5_q_
}else{ }S84^2J_
this.totalCount = 0; 04{*iS95J
} p&'oJy.P
} PMPB}-d
.{U@Hva_K
publicint[] getIndexes(){ f?)BAah
return indexes; y>}dKbCN
} S !Dq8
3D<s#
publicvoid setIndexes(int[] indexes){ dd4g?):
this.indexes = indexes; #P[d?pY
} oJ}!qrrH
~"-+BG(5
publicint getStartIndex(){ >
cFH=um
return startIndex; os/_ObPiX
} yhF{
cK=
yu8xTh$:
publicvoid setStartIndex(int startIndex){ k@QU<cvI
if(totalCount <= 0) Nm;(M=
this.startIndex = 0; Hrb67a%b
elseif(startIndex >= totalCount) LRNgpjE}
this.startIndex = indexes &|rh~;:jUX
{OHaI ;
[indexes.length - 1]; M1(+_W`
elseif(startIndex < 0) -P"9KnsO
this.startIndex = 0; Bn>"lDf,
else{ uA]Z"
this.startIndex = indexes yk
r5bS
]ADj9
[startIndex / pageSize]; Y![m'q}K
} @uru4>1_dy
} J'99
@wa2Z
publicint getNextIndex(){ ]PlDe8
int nextIndex = getStartIndex() + ,khB*h14;h
t+C9QXY
pageSize; bvVEV
if(nextIndex >= totalCount) dg#w/}}m
return getStartIndex(); l)@Zuh
else lP$bxUNt
return nextIndex; JBY`Y]V3
} >^mNIfdE^=
!ho~@sc{W
publicint getPreviousIndex(){ 1eiV[z$?
int previousIndex = getStartIndex() - 3{wr*L1%-~
ySC;;k'
pageSize; A6D.bJ)
if(previousIndex < 0) _^{!`*S
return0; xqV>m
else 7S"W7O1>
return previousIndex; {J_1.uN=
} D|zlC,J,
X}XTEk3[
} 6 <&jY
t^N
92$|
a>w@9
VKzY6
抽象业务类 z
D&5R/I
java代码: d1&RK2
Mlr]-Gu5Z
Grot3a
/** P3[!-sv
* Created on 2005-7-12 uK_ Q l\d
*/ )"Ef* /+
package com.javaeye.common.business; lHg&|S&J
G-5wv
import java.io.Serializable; Ps<6 kQ(
import java.util.List; w.tQ)x1h
rgth2y]
import org.hibernate.Criteria; }d<xbL!#
import org.hibernate.HibernateException; ^Rgm3?7
import org.hibernate.Session; Z^P]-CB|6A
import org.hibernate.criterion.DetachedCriteria; :` FL95
import org.hibernate.criterion.Projections; (wxdT6RVm\
import |$$gj[+^
z&a%_
]Q*
org.springframework.orm.hibernate3.HibernateCallback; ;W ZA
import ;'^5$q
WD"3W)!
org.springframework.orm.hibernate3.support.HibernateDaoS bf~gWzA
cQ:Y@f 9
upport; z5~{WAAI
k-o(Q"[ '
import com.javaeye.common.util.PaginationSupport; l)JNNcej
() l#}H`m
public abstract class AbstractManager extends -Oj}PGj$e\
a'sa{>
HibernateDaoSupport { 4';~@IBf
%by8i1HR
privateboolean cacheQueries = false; L;wfTZa
{Q/XV=
privateString queryCacheRegion; [&IJy
1J(` kQ)c
publicvoid setCacheQueries(boolean z|';Y!kQ
`5VEGSP]
cacheQueries){ ~d+.w%Z`
this.cacheQueries = cacheQueries; Gz>M Y4+G
} <<xUh|zE
B/P E{ /
publicvoid setQueryCacheRegion(String 9XU"Ppv
942(a
queryCacheRegion){ Ww8C}2g3
this.queryCacheRegion = 5C03)Go3Z
w!~%v
#
queryCacheRegion; YMlnC7?_/
} f:/[
wHGiN9A+
publicvoid save(finalObject entity){ (:JX;<-
getHibernateTemplate().save(entity); Pfy2PpA
} |AY`OVgcKD
l4 @
publicvoid persist(finalObject entity){ :/F=j;o
getHibernateTemplate().save(entity); }sbh|#
} Eb9 eEa<W
K^H{B& b8
publicvoid update(finalObject entity){ $d<vPpJ3
getHibernateTemplate().update(entity); Ek0zFnb[Gx
} O$'BJKj-4
?*2DR:o>@
publicvoid delete(finalObject entity){ (k{rn3,
getHibernateTemplate().delete(entity); ^lF'KW$
} $L~?!u&N
J>H$4t#HX
publicObject load(finalClass entity, i{#5=np H
^jY'Hj.Bs
finalSerializable id){ RnvPqNs
return getHibernateTemplate().load oCl
$ 0x
QkEIV<T&)l
(entity, id); F XpI-?#E<
} ]n8
5.DF
r2KfZ>tWg"
publicObject get(finalClass entity, -vRZCIj!
r&^xg`i[z>
finalSerializable id){ MfX1&/Z+
return getHibernateTemplate().get 3LxhQVx2
>mk}
(entity, id); })I_@\q
} Z6.0X{6nA
.?16w`Y
publicList findAll(finalClass entity){ a>3#z2#
return getHibernateTemplate().find("from O
WJv<3
U
Bo[iZ|%
" + entity.getName()); F&ud|X=m
} -r.Qy(}p
:h4Nfz(
publicList findByNamedQuery(finalString &#keI.,
j|Q*L<J
namedQuery){ \Vc-W|e
return getHibernateTemplate @
m' zm:
xJ2DkZ
().findByNamedQuery(namedQuery); z0@{5e$#Y
} oWJ0>)
/QA:`_</oh
publicList findByNamedQuery(finalString query, k<bA\5K
?3f-"K_r
finalObject parameter){ L7\rx w
return getHibernateTemplate XXx]~m
fyRSg B00$
().findByNamedQuery(query, parameter); Ia>07av
} b7thu5
{LwV&u(
publicList findByNamedQuery(finalString query, K
*<+K<Tp
*%[L
@WF
finalObject[] parameters){ ,'7 X|z/_>
return getHibernateTemplate -y@#
^SrJ
rA=iBb3`
().findByNamedQuery(query, parameters); nUp, %z[
} z5V~m_RO
RDX$Wy$@L
publicList find(finalString query){ E%B:6
return getHibernateTemplate().find B+8lp4V9%
1E1oy(\V
(query); w1#1s|
} [iT*L)R4
m$ubxI)
publicList find(finalString query, finalObject hd~3I4D
2{- };
parameter){ 4[&L<D6h
return getHibernateTemplate().find m%=]
j<A
vpnOc2 -
(query, parameter); +>w %j&B
} '@jP$6T&
D-v}@tS'
public PaginationSupport findPageByCriteria jcC"SqL
uR;m<wPH,f
(final DetachedCriteria detachedCriteria){ d*M:PjG@
return findPageByCriteria z 1~2w:
VL[}
(detachedCriteria, PaginationSupport.PAGESIZE, 0); n`W7g@Sg#I
} Rxl )[\A*
`$fKS24u
public PaginationSupport findPageByCriteria WbIf)\
^]{)gk8P~2
(final DetachedCriteria detachedCriteria, finalint V2v}F=
?}mbp4+j[
startIndex){ q_J)68B R
return findPageByCriteria bhqV2y*'
{.,-lFb\
(detachedCriteria, PaginationSupport.PAGESIZE, +NM`y=@@
3Z taj^v
startIndex); pA~eGar_J
} +\Zr\fOe|%
j\/Rjn+:[
public PaginationSupport findPageByCriteria "DpgX8lG_
.%\lYk]
(final DetachedCriteria detachedCriteria, finalint rV5QKz6'
"\CUHr9k
pageSize, [v,Y-}wQ)
finalint startIndex){ t'7A-K=k3
return(PaginationSupport) vrGx<0$
#9's^}i
getHibernateTemplate().execute(new HibernateCallback(){ eeix-Wt*E
publicObject doInHibernate (8XP7c]5
x/)o'#d$|l
(Session session)throws HibernateException { @v:p)|Ne;
Criteria criteria = (E*pM$
/x2MW5H
detachedCriteria.getExecutableCriteria(session); 8c1ma
int totalCount = Ig.9:v`
o 9?#;B$
((Integer) criteria.setProjection(Projections.rowCount [f8mh88r
)C1ihm!7\
()).uniqueResult()).intValue(); GIs
*;ps7w
criteria.setProjection 20NotCM
<$:Hf@tpMo
(null); YXFUZ9a#e
List items =
l
;fO]{
r;~2NxMF/
criteria.setFirstResult(startIndex).setMaxResults pOmHxFOOK
=Zt7}V
(pageSize).list(); HOY@<'
PaginationSupport ps = fxcCz 5
'^6jRI,
new PaginationSupport(items, totalCount, pageSize, ZD`9Ez)5
(Y[q2b
startIndex); ;_ TP Jy
return ps; vIK+18v7
} 7)FI_uW
}, true); Y/Dah*
} v"~0 3-SX
Y6R+i0guz
public List findAllByCriteria(final U~nW>WJ+.
2Jl$/W 3
DetachedCriteria detachedCriteria){ EPn0ZwnS:M
return(List) getHibernateTemplate Ra~|;(
%d
Y!0ZwwW
().execute(new HibernateCallback(){ k04CSzE"%
publicObject doInHibernate eGEeWJ}[$
1|Q-|jq`
(Session session)throws HibernateException { F Tk`Mq
Criteria criteria = 920 o]Dh=t
{i!@C(M3
detachedCriteria.getExecutableCriteria(session); %aHQIoxg
return criteria.list(); xUw)mUn@N
} -Y:^<C^^&8
}, true); VW%eB
} Zf [#~4
V9SkB3-'
public int getCountByCriteria(final ndB [f
6.0/asN}
DetachedCriteria detachedCriteria){ !=t.AgmL
Integer count = (Integer) kH9fK80
T=-$ok`G
getHibernateTemplate().execute(new HibernateCallback(){ V]fsjpvlmr
publicObject doInHibernate )RZ:\:c
{YT@$K]w,
(Session session)throws HibernateException { !92zC._
Criteria criteria = c1CUG1i
mY& HK)
detachedCriteria.getExecutableCriteria(session); [$+N"4
return fdCN?p[_
Ac,Qj`'V
criteria.setProjection(Projections.rowCount uLK4tQ
0.4Q-?J
()).uniqueResult(); ]
1:pnd
} ML= :&M!ao
}, true); -sqoE*K[8
return count.intValue(); UwQyAD]Ht
} jykY8;4
} Y{v\m(D
~6HaZlBB
to%n2^^K
y G{;kJ P
2dpTU=K4
x[w!buV0\
用户在web层构造查询条件detachedCriteria,和可选的 kNnI$(H"H
Dg_AoC
startIndex,调用业务bean的相应findByCriteria方法,返回一个 %Q2<bj]
iAWd
9x
PaginationSupport的实例ps。 __Tg1A
PL6f**{-
ps.getItems()得到已分页好的结果集 ~ v21b?
ps.getIndexes()得到分页索引的数组 =Kh1HU.F
ps.getTotalCount()得到总结果数 '
6#en9{L
ps.getStartIndex()当前分页索引 Kz`g Q |S
ps.getNextIndex()下一页索引 { :~D
ps.getPreviousIndex()上一页索引 #383W)n
IBY(wx[5S
}.$5'VGO
tPb$ua|
B[8`l} t
pndAXO:v
Z8yt8O
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 A@I ( &Z
C2/B1ba
,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 }vGWlNd#g
%=t8
一下代码重构了。 4#c-?mh_
1p%75VW
我把原本我的做法也提供出来供大家讨论吧: Vr1yj
zG0191f
首先,为了实现分页查询,我封装了一个Page类: q8_8rp-@
java代码: <JyF5
74u_YA<"
x6BO%1
/*Created on 2005-4-14*/ 'U8% !
package org.flyware.util.page; o7A+O%dX
2&+Nr+P
/** ^o@N.+`&<
* @author Joa u#&ZD|
* =,4iMENm!
*/ X":T>)J-
publicclass Page { I6B`G Im5
q(C <w
/** imply if the page has previous page */ ]g0h7q)79
privateboolean hasPrePage; o8A1cb4<T
D+u#!t[q
/** imply if the page has next page */ X\yy\`o
privateboolean hasNextPage; 4sCzUvI~Y1
5?{ytNCY
/** the number of every page */ `Zm-F
privateint everyPage; F CbU> 1R
HL*Fs /W
/** the total page number */ /`b(} m
privateint totalPage; 2xx
c<c"n'
/** the number of current page */ HT:
p'Yyi
privateint currentPage; *sPG,6>
j0F'I*Z3
/** the begin index of the records by the current P
nxx W?
R
| &+g\{;
query */ 0:SR29(p1
privateint beginIndex; 3cH`>#c
(Q /Kp*a
$0OWPC1
/** The default constructor */ ER ^#J**
public Page(){ [|)Eyd[G
X4bB
} 0M=U>g)
`7))[._
/** construct the page by everyPage BnL [C:|
* @param everyPage S.#IC
lV
* */ k m(Mv
public Page(int everyPage){ Fz 6&.f
this.everyPage = everyPage; W_sAk~uK/
} f L}3I(VK
IB
sQaxt.
/** The whole constructor */ <:tD m
public Page(boolean hasPrePage, boolean hasNextPage, e/{1u$
^q$m>|KI
:{YOJDtR
int everyPage, int totalPage, <Z -d5D>
int currentPage, int beginIndex){ 1l(_SD;90t
this.hasPrePage = hasPrePage; zv%9?:
this.hasNextPage = hasNextPage; p903*F^[,
this.everyPage = everyPage; rpZ^R}B%*v
this.totalPage = totalPage; Gd]!D~[1
this.currentPage = currentPage; x^ J}]5{0
this.beginIndex = beginIndex; |1@/gqa
} l?AWG&
1$]hyC/f
/** Cqy)+x_OQ,
* @return N!u(G
* Returns the beginIndex. iLyJ7zby
*/ 6u'+#nm
publicint getBeginIndex(){ a+--2+~=
return beginIndex; !RJuH;8
} aUBGp: (
f.~-31
/** wj'5D0
* @param beginIndex tsLi5;KA]
* The beginIndex to set. )l|/lj
*/ Ca?:x tt
publicvoid setBeginIndex(int beginIndex){ Pl>S1
this.beginIndex = beginIndex; t5qNfiKC
} %nmD>QCe
6]/LrM, 23
/** h
dw~AGO#
* @return >H*?ktcW
* Returns the currentPage. F_?aoP&5
*/ [ ;$(;
publicint getCurrentPage(){ 20O\@}2q2M
return currentPage; n'&Cr0{
} _2wU(XYH
!='?+Ysxs
/** xjplJ'jB
* @param currentPage m-M.F9R
* The currentPage to set. nisW<Q`uB
*/ %pR:.u|
publicvoid setCurrentPage(int currentPage){ :+G1=TuXw~
this.currentPage = currentPage; BfcpB)N&.K
} *A>I)a<:
QNk\y@yKw
/** ?/SI A9VK
* @return 3V,$FS]
* Returns the everyPage. 4}4K6y<q
*/ h]DS$WZ
publicint getEveryPage(){ 3%g\)Cs
return everyPage; R43yr+p
} 5$(qnOi
ncGg@$E
/** L*rND15
* @param everyPage *gJ:irah
* The everyPage to set. #-0}r
*/ \KGi54&Y
publicvoid setEveryPage(int everyPage){ sI@y)z
this.everyPage = everyPage; 3Pj 6(cf
} A`Nk gVq5:
:z^VI M
/** r fl-(_3
* @return @-7h}2P Q
* Returns the hasNextPage. )YB@6TiD
*/ LFi 8@
publicboolean getHasNextPage(){ {GTOHJ2
return hasNextPage; E>bK-jG
} bpQ5B'9
#`1@4,iC
/** sbxOnwP\
* @param hasNextPage tML[~AZh
* The hasNextPage to set. ,<pk&54.@'
*/ ]
BJ]
publicvoid setHasNextPage(boolean hasNextPage){ ~w&_l57
this.hasNextPage = hasNextPage; 8:x{
} Q*W`mFul
)YP"\E
/** gCVgL]jj(
* @return y)s+ /Teb
* Returns the hasPrePage. *~t&Ux#hj
*/ vy
<(1\
publicboolean getHasPrePage(){ <3[,bTIk
return hasPrePage; Y[hTO.LF
} yBd#*3K1
U]aH4N
/** K>"]*#aBv
* @param hasPrePage ?"d25LyN
* The hasPrePage to set. WSt&?+Y
*/ x*Lm{c5+
publicvoid setHasPrePage(boolean hasPrePage){ u~WE}VC
this.hasPrePage = hasPrePage; Ik4FVL8~
} hzT,0<nw
O%1X[
/** ?k5m1,fHW
* @return Returns the totalPage. D8`dEB2|S
* !rK,_wH
*/ qmWK8}F.cE
publicint getTotalPage(){ 6`ZHFem
return totalPage; vZDM}u
} 0/1Ay{ns
YA";&|V
/** KA=cIm
* @param totalPage 1ZUmMa1(
* The totalPage to set. Rl. YF+YH
*/ *A2D}X3s
publicvoid setTotalPage(int totalPage){ W?`%it5
this.totalPage = totalPage; w^_[(9
`
} b5-W K;
-^Pn4y]A)
} k>2tC<
=JqKdLH
tX<.
Ud
2MV!@rx
jkzC^aG
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 l7+[Zn/v *
nB;yS<
个PageUtil,负责对Page对象进行构造: 4iXB`@k
java代码: R\^n2gK
u%o2BLx
4RLuv?,)~
/*Created on 2005-4-14*/ &<oZl.T
package org.flyware.util.page; ([mC!d@a
\:'|4D]'I
import org.apache.commons.logging.Log; a2'si}'3
import org.apache.commons.logging.LogFactory; MmZs|pXk
9kpCn.rJ
/** yF~iVt
* @author Joa 6N6}3J5
* qu}&4_`%:V
*/ 4
Qo(Wl
publicclass PageUtil { q ,C)AZ
W)RCo}f
privatestaticfinal Log logger = LogFactory.getLog G2
#QWG5
(PageUtil.class); k*?Axk#
.4t-5,7s%
/** 1ymq7F(2
* Use the origin page to create a new page @T
}p.
* @param page /^m3?q[a
* @param totalRecords 82EH'C
* @return hC nqe
*/ @TvoCDeI
publicstatic Page createPage(Page page, int z_A:MoYfo
|i}5vT78
totalRecords){ RPXkf71iM
return createPage(page.getEveryPage(), 0~)_/yx?S
+&U{>?.u
page.getCurrentPage(), totalRecords); |JR;E$
} 2tEA8F~k
v0d<P2ix
/** C6!P8qX
* the basic page utils not including exception B!;qz[]I
-F]0Py8(
handler FL,av>mV
* @param everyPage l'K3)yQEJ
* @param currentPage YFGQPg
* @param totalRecords SWrt 4G
* @return page 5ree3 quh
*/ T!iRg=<bz
publicstatic Page createPage(int everyPage, int snl$v
voD0u
currentPage, int totalRecords){ >h[ {_+
everyPage = getEveryPage(everyPage); MPn
6sf9M
currentPage = getCurrentPage(currentPage); $69ef[b
int beginIndex = getBeginIndex(everyPage, |?kZfr&9q
miq"3
currentPage); gvoo1 Sa
int totalPage = getTotalPage(everyPage, ThvVLK
e%B;8)7
totalRecords); ~&UfnO
boolean hasNextPage = hasNextPage(currentPage, ZjOUk;H?
`;:zZ8*
totalPage); B?-~f^*,jG
boolean hasPrePage = hasPrePage(currentPage);
a2z1/Nh
cP]5Qz
returnnew Page(hasPrePage, hasNextPage, SU {U+
everyPage, totalPage, B(omD3jzN
currentPage, ;'|Mt)\
uia[>&2
beginIndex); 3hPj;-u
} Zl:Z31
}gfs
privatestaticint getEveryPage(int everyPage){ ~@v<B
I
return everyPage == 0 ? 10 : everyPage; ?)60JWOJ1
} #wvmVB. 5~
:'t+*{ff
privatestaticint getCurrentPage(int currentPage){ W{{{c2 .
return currentPage == 0 ? 1 : currentPage; nJ ZQRRa:C
} ?eU=xO
gmU0/z3&
privatestaticint getBeginIndex(int everyPage, int Gp PlO]
]h`<E~
currentPage){ xpzQ"'be
return(currentPage - 1) * everyPage; Hy_}e"
} 2".^Ma^D!
clcj5=:
privatestaticint getTotalPage(int everyPage, int uqN:I)>[P
s-z*Lq*
totalRecords){ QIcg4\d%s
int totalPage = 0; 9T#JlV
EE^
N01<"\
if(totalRecords % everyPage == 0) 1l~(J:DT
totalPage = totalRecords / everyPage; YXBU9T{r
else (Vvs:h%H
totalPage = totalRecords / everyPage + 1 ; Ep@NT+VnI
tR;? o,T
return totalPage; s*XwU
} b')Lj]%;k
:Hn*|+'
privatestaticboolean hasPrePage(int currentPage){ ^LO`6,
return currentPage == 1 ? false : true; \k8| 3Y~g
} 9qqzCMrI0e
Y?^1=9?6
privatestaticboolean hasNextPage(int currentPage, &>0ape
+mr\AAFn
int totalPage){ @`hnp:
return currentPage == totalPage || totalPage == JLZ[sWP='
~I+}u]J
0 ? false : true; q,W6wM;,E
} pO;BX5(x
L&i _
RCS91[
} f a9n6uT
cITF=Ez
:EXH8n&|
N~w4|q!]
mJ>@Dh3>G
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。 bhIyq4N
r%QnV0L^
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 U;QN+fF]u
CQLh;W`Dc
做法如下: XO=UKk+EK
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 R
m{\ R
@rTAbEk{U
的信息,和一个结果集List: "DW; 6<m
java代码: )k@+8Yfa1p
S b9In_*
0
Ww
}qK|D
/*Created on 2005-6-13*/ \[-z4Fxg|'
package com.adt.bo; LEUD6 M+~t
kRyt|ryWh
import java.util.List; >-~2:d\M3
0B4&!J
import org.flyware.util.page.Page; q$;'Fy%oy
CkJU5D
/** xSQ0] vE
* @author Joa q0}?F
*/ /eoS$q
publicclass Result { #2F 6}
OfR\8hAY
private Page page; ""dX4^gtU
~+y0UEtq7
private List content; /!r#=enG7
Vs)%*1><
/** UacGq,
* The default constructor ATeXOe
*/ W[dMf!(
public Result(){ )BuS'oB
super(); n(mS
} }>
51oBgk_
e<wRA["
/** 0P5!fXs*
* The constructor using fields 9}4EW4
* .?TPoqs7Z
* @param page "dKYJ&$
* @param content $J~~.PUXQ
*/ +Oae3VFf;
public Result(Page page, List content){ "!yKX(aTX
this.page = page; 9"@P.8_
this.content = content; jJpSn[{
} r "^{?0
%HRFH
/** >PsP y.
* @return Returns the content. a?+Ni|+
*/ !
Z e
publicList getContent(){ S;o U'KOY
return content; )$#r6fQO
} dh7PpuN{
_HT*>-B
/** 0I.9m[<Fc
* @return Returns the page. 3X+uJb2
*/ !lSxBr[dQ
public Page getPage(){ c=YJ:&/5&
return page; b&$ ?.z
} =A6/D
`0r=ND5.
/** (1bz.N8z
* @param content `.# l_-U{
* The content to set. @G
vDl=.
*/ G -U%
public void setContent(List content){ pai>6p
this.content = content; ."m6zq
} u}QB-oU
Dm@wTt8N(
/** $jYwV0
* @param page ub"(,k P
* The page to set. s$Il;
*/ {__Z\D2I
publicvoid setPage(Page page){ !b O8apn
this.page = page; JJnZbJti
} SL;\S74
} Z=O 2tR
7Q<uk[d0
+uF!.!}
~Od4(
}/G
Sx,O)
2. 编写业务逻辑接口,并实现它(UserManager, K_V44f1f
@jW_
rj:<
UserManagerImpl) i<g|+}I
java代码: ObC
<v?9:}
(}Ql#q
K
/*Created on 2005-7-15*/
qO
package com.adt.service; >G2o
'3>kD H+
import net.sf.hibernate.HibernateException; +#5nk,1c>
j+3~
import org.flyware.util.page.Page; ]JX0:'x^
TEZ^Ia
import com.adt.bo.Result; o~
.[sn5l-
W{Cc wq
/** QdKxuG
* @author Joa (o_fY.
*/ %/dYSC
publicinterface UserManager { P'#m1ntxQ
fGiN`j}j
public Result listUser(Page page)throws y2V9!
$]CZ]EWts
HibernateException; Y&xmy|O#
ce{GpmW
} /&=E=S6
h<.G^c)
6Q,-ZM=Z_p
#Zpp*S55
8<$6ufvOv
java代码: j380=?7
Qp7|p
{&G7 Xa
/*Created on 2005-7-15*/ w,NK]<dU@
package com.adt.service.impl; pN<wO1\9
lgZ3=h
import java.util.List; 4Vj|k\vE4
Lj"~6l`)
import net.sf.hibernate.HibernateException; xm>RLx}9
uROt h_/
import org.flyware.util.page.Page; tRYMK+
import org.flyware.util.page.PageUtil; >9W ;u`
. m_y5J
import com.adt.bo.Result; eL9RrSXz
import com.adt.dao.UserDAO; E|D~:M%~
import com.adt.exception.ObjectNotFoundException; *=L3bBu?
import com.adt.service.UserManager; E%\i NU!
ZLdvzH@'
/** cgsM]2ZYs
* @author Joa -@%*~^~z'
*/ |KF X0*70
publicclass UserManagerImpl implements UserManager { 'v4#mf
m~9Qx`fi`
private UserDAO userDAO; 1)u
3
PIo/|1
/** `rC9i5:
* @param userDAO The userDAO to set. 1oaiA/bq
*/ .-+_>br~
publicvoid setUserDAO(UserDAO userDAO){ v?rjQ'OP
this.userDAO = userDAO; ]]$s"F<
} *L8Pj`zR
Q44Pg$jp
/* (non-Javadoc) ks7g*; 3{@
* @see com.adt.service.UserManager#listUser PYqx&om
4VPL
-":6
(org.flyware.util.page.Page) @`aR*B
*/ IC+Z C
public Result listUser(Page page)throws KzZ!
CB\
rX6"w31
HibernateException, ObjectNotFoundException { m;{_%oQ;
int totalRecords = userDAO.getUserCount(); K1Nhz'^=D
if(totalRecords == 0) .]%PnJM9K
throw new ObjectNotFoundException T[s_w-<7$
@(PYeXdV6&
("userNotExist"); I,vy__sZ
page = PageUtil.createPage(page, totalRecords); 7/NXb
List users = userDAO.getUserByPage(page); oK@!yYv
returnnew Result(page, users); S =q.Y
} Lm\N`
.ps'{rl8
} au2ieZZ[
;A~S){
T%K(opISc(
tfj6#{M5
i$)bZr\
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 &^4\Rx_I
_*6nTSL
询,接下来编写UserDAO的代码: r_T\%
3. UserDAO 和 UserDAOImpl: ZA zn-n
java代码: T F&xiL^
vrdlI^
wly#|
/*Created on 2005-7-15*/ +vaz gO<u
package com.adt.dao; Ix g.^>62
%(Sy XZ
import java.util.List; M(x5D;db/
y%k\=:m
import org.flyware.util.page.Page; p>=YPi/d
M*BDrM
import net.sf.hibernate.HibernateException; 7+JQaYO`"
kVw5z3]Xg
/** KgX~PP>
* @author Joa [wP;g'F
*/ O^|dc=
publicinterface UserDAO extends BaseDAO { R6]/g
,xB&{J
publicList getUserByName(String name)throws Bv
\ihUg/
,K .P,z~*
HibernateException; p!>FPS
=2pGbD;*
publicint getUserCount()throws HibernateException; U 9TEC)
Lv+lLK
publicList getUserByPage(Page page)throws *W,"UL6U8y
E~ _2Jf\U
HibernateException; |E0>-\6
!Sfy'v.
} R!;tF|]
8s pGDg\g
CL|t!+wU/
:}TT1@
ej>8$^y
java代码: AU} e^1h
z:bxnM2\
F"VNz^6laV
/*Created on 2005-7-15*/ 5#s?rA%u
package com.adt.dao.impl; *:bNK5I.t
&Qy_= -]
import java.util.List; bKj#HHy\I
X0J@c "%0
import org.flyware.util.page.Page; a \B<(R.
e~=fo#*2?@
import net.sf.hibernate.HibernateException; q.FgX
import net.sf.hibernate.Query; 0e9W>J9
1w'iD
X
import com.adt.dao.UserDAO; 16)@<7b]J
|_8::kir:
/** g<{/mxv/
* @author Joa RK#e7
*/ GrjL9+|x
public class UserDAOImpl extends BaseDAOHibernateImpl _aL:XKM
^RrufwUA
implements UserDAO { OaRtGJnR
Q*Per;%J
/* (non-Javadoc) #ebT$hf30
* @see com.adt.dao.UserDAO#getUserByName @FIR9XJ
e*jt(p[Ge
(java.lang.String) NmYSk6kWJ
*/ rc1EJ(c
publicList getUserByName(String name)throws e@*Gnh<&
u&?J+
HibernateException { ]78I
String querySentence = "FROM user in class *5 ]fjh{
1u75
com.adt.po.User WHERE user.name=:name"; ZN-J!e"`
Query query = getSession().createQuery +"6_rbeuO
!L:!X88
(querySentence); /lkIbmV
query.setParameter("name", name); 3g9xTG);eA
return query.list(); 7)S`AQ2:)
} oQI3Yz
sguE{!BO
/* (non-Javadoc) +b1(sk=4z
* @see com.adt.dao.UserDAO#getUserCount() xcwyn\93)
*/ ?~uTbNR
publicint getUserCount()throws HibernateException { rcMVYSj0
int count = 0; 1i4KZ"A5+
String querySentence = "SELECT count(*) FROM 0vNEl3f'O
96T.xT>&
user in class com.adt.po.User"; HE(|x1C)j
Query query = getSession().createQuery ]S<eO6z
wQWokpP;T7
(querySentence); 4_3Jpz*
count = ((Integer)query.iterate().next v>YdPQky
{\jh?P|
()).intValue(); -q|K\>tgU
return count; } *|_P
} BusD}9QqB
=HmV0
/* (non-Javadoc) gN$.2+:
* @see com.adt.dao.UserDAO#getUserByPage >Jt,TMMlt
cOcF VPQ
(org.flyware.util.page.Page) p;`jmF
*/ z8{ kwz
publicList getUserByPage(Page page)throws trnjOm
&Z/aM?
HibernateException { `Gzukh
String querySentence = "FROM user in class =z'- B~
_HX1E
com.adt.po.User"; t%ye:
Query query = getSession().createQuery f1(V~{N,+
5p}Y6Lc\j
(querySentence); v~e@:7d i
query.setFirstResult(page.getBeginIndex()) j*nZ
.setMaxResults(page.getEveryPage()); 8PB(<|}u
return query.list(); _'0HkT{I
} r-v;A
>J^bs &j
} 0? (
WM5s
Wk"4mq
V|KYkEl
r1
'; ,DgR;'
至此,一个完整的分页程序完成。前台的只需要调用 ne] |\]
n3t1'_/TU}
userManager.listUser(page)即可得到一个Page对象和结果集对象 h
1G`z
$'*@g1vY
的综合体,而传入的参数page对象则可以由前台传入,如果用 eyf\j,xP&
iM+K&\{_h
webwork,甚至可以直接在配置文件中指定。 fu'iG7U M
%l%5Q;t
下面给出一个webwork调用示例: -hj@^Auf
java代码: Ks.m5R
u"XqWLTV
xr+K:
bw
/*Created on 2005-6-17*/ |F[E h
~
package com.adt.action.user; Vd~{SS2>
Hq[d!qc
import java.util.List; ]J+}WR
YMOy6C
import org.apache.commons.logging.Log; #-dfG.*
import org.apache.commons.logging.LogFactory; JUXIE y^
import org.flyware.util.page.Page; pXf@Y}mH
P1)f-:;
import com.adt.bo.Result; W#87T_7T[
import com.adt.service.UserService; U.is:&]E
import com.opensymphony.xwork.Action; y}*rRm.:
l|z
'Lwwm5
/** ?9xaBWf
* @author Joa ?F]Yebp^
*/ Xd/gvg{??0
publicclass ListUser implementsAction{ y
E-H-r~I
8Kt_irD
privatestaticfinal Log logger = LogFactory.getLog ^IGutZov
#Ki(9oWd
(ListUser.class); x=Z\c,@O
n_\VG[f
private UserService userService; U<{8nMB
w^Qb9vTa8
private Page page; ln%xp)t
J/S 47J~
privateList users; _Qg^>}]A1
</F@5*
/* :W(3<D7\
* (non-Javadoc) LWE[]1=
* nlJ~Q_E(
* @see com.opensymphony.xwork.Action#execute() o:B?gDM
*/ )j(13faW|
publicString execute()throwsException{ B2t.;uz(,
Result result = userService.listUser(page); 5('_7l
page = result.getPage(); $~vy,^
users = result.getContent(); p>4$&-
return SUCCESS; JF!?i6V
} ~6m-2-14q
uqwB`<>KJ
/** fmZ5rmw!
* @return Returns the page. P5/K?I~/So
*/ 7sKN`
public Page getPage(){ $s<,xY 9
return page; #A<|hh
} J.Mj76\_
>(5*y=\i
/** nD6mLNi%a
* @return Returns the users. m<)0XE6w
*/ Z&FC:4!!
publicList getUsers(){ g*C&Pr3
return users; :acnrW>i[@
} +g,:!5pg
{Ts@#V=:
/** N<o3pX2i]
* @param page ._@Scd
* The page to set. vWY}+#
*/ su6x
okt
publicvoid setPage(Page page){ Jcf'Zw"\
this.page = page; vRa|lGeW
} p6m](Jg
C{>@b:]p
/** nB"r<?n<
* @param users u4TU"r("A
* The users to set. nM:e<`r
*/ }R-eQT
publicvoid setUsers(List users){ wuE] ju<
this.users = users; 0STtwfTr:
} `$oGgz6ZT
)1ia;6}
/** wy6> ^_z
* @param userService 2|]$hjs
* The userService to set. qS<a5 `EA
*/ H&jK|]UXoO
publicvoid setUserService(UserService userService){ W5,e;4/hL
this.userService = userService; WccTR
aq
} ^$qr6+
} edld(/wu~
x*td
nor&
z`UL)W
cF!ygz//
=ic"K6mhq
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, KrE:ilm#^Y
K +n
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 2[f8"'lUQ
?dMyhU}
么只需要: z{:T~s
java代码: P#-9{T
*y[i~{7:
Jydz2
zt!
<?xml version="1.0"?> )6U&^9=
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ;okFm
`tA~"J$32l
1.0//EN" "http://www.opensymphony.com/xwork/xwork- K] ;`
j`jF{k b
1.0.dtd"> !4-B
xeNY\
3wZA,Z
<xwork> z%cq%P8g
O8:$sei$
<package name="user" extends="webwork- .;j} :<
k(1]!c4J0
interceptors"> m<L.H33'
rT$J0"*=
<!-- The default interceptor stack name =9$hZ c
2w)[1s[
--> p12'^i |
<default-interceptor-ref `Wq4k>J}*
2g
shiY8_
name="myDefaultWebStack"/> :*|%g
2u 8z>/G
<action name="listUser" lM
]n
&}}c>]m
class="com.adt.action.user.ListUser"> gN#&Ag<?
<param w$I<WS{J:Z
S9kagiFX\
name="page.everyPage">10</param> 8a{S*
<result BeP]M1\?>
q#9JJWSs
name="success">/user/user_list.jsp</result> =^ur@E
</action> :m*r(i3
k(l
</package> &?L
K>QV
)>,;
GVu"
</xwork> tlhYk=yq
"e]1|~
{2wfv2hQ
^q``f%Xt
7A0D[?^xe
m(Ghe2T:
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 #B7_5y^
qOaI4JP@
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 _ dFZR
o&45y&
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 =#)Zm?[;
5J!ncLNm{
j8/rd
I*cB
Ha
.)Xyzd
我写的一个用于分页的类,用了泛型了,hoho g/H:`J
<vS J<WY
java代码: b+/XVEsr
]pUf[^4
,>(/}=Z.
package com.intokr.util; i}SJ
9MfBsp}c
import java.util.List; E?%SOU<
5!WQ
/** Y r3h=XY
* 用于分页的类<br> v:otR%yt
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 1=LI))nV
* TAfLC)
* @version 0.01 5 :O7c Br
* @author cheng 3I0=^>A
*/ ,G2]3
3Z
public class Paginator<E> { ^R\et.W`s
privateint count = 0; // 总记录数 !OwRx5
privateint p = 1; // 页编号 :4 9ttJl
privateint num = 20; // 每页的记录数 yZ7aH|Q81B
privateList<E> results = null; // 结果 _@U?;73"5
]Tmx;[D
/** jSMvZJX3n
* 结果总数 y&8' V\
*/ +E.}k!y
publicint getCount(){ i4 BCm/h
return count; 8r"$o1!
} 6J/"1_
jP*5(*[&y
publicvoid setCount(int count){ z?o16o-:
this.count = count; r$3{1HXc
} O'tVZ!C#J
#i$/qk=N
/** "#7~}ZB
* 本结果所在的页码,从1开始 z"4UObVs
* ~!o\uTVr
* @return Returns the pageNo. ^kg[n908Nw
*/ w74)kIi
publicint getP(){ 32DT]{-N!
return p; CXC,@T
} QcZ*dI7]:
l| 1O9I0Gd
/** /?<tjK' "H
* if(p<=0) p=1 *#ccz
* =HJ)!(
* @param p tqI]S
X
*/ V&7jd7
2{
publicvoid setP(int p){ qmzg68
if(p <= 0) h\+U+?u
p = 1; oK cgP
this.p = p; py9zDWk~
} R@lmX%Z1
4VtI8f!
/** 4-P'e%S
* 每页记录数量 {(mT,}`4
*/ rn1^6qy)
publicint getNum(){ sW/^82(dM
return num; ~G0\57;h
} HsA4NRF'7
u\~dsD2)q
/** r;3{%S._
* if(num<1) num=1 g\sW2qXEw
*/ |&JCf=
publicvoid setNum(int num){ 88 fH!6b
if(num < 1) T /iKz
num = 1; Yh`P+L
this.num = num; VCOz?Y*
} t*<@>] k
DDdMWH^o7
/** J%|!KQl
* 获得总页数 9 *>@s
*/ *E"QFirk0
publicint getPageNum(){ 8KqrB!
return(count - 1) / num + 1; @ 2r9JqR[=
} b21c} rI3
r:h\{DVf
/** OnO56,+S^
* 获得本页的开始编号,为 (p-1)*num+1 Q;p?.GI?-
*/ oqzx}?0
publicint getStart(){ #:rywz+
return(p - 1) * num + 1; xO8-vmf2
} :1Jg;G
}?f%cRT$
/** 0IHcyb
* @return Returns the results. J}?F4
*/ $N$
ZJC6(@
publicList<E> getResults(){ I@dS/
return results; sSVgDQ~q
} yya"*]*S
}UwDHq=
public void setResults(List<E> results){ @4h{#
this.results = results; _M
n7zt1^
} U=_O*n?N-d
XA`<*QC<
public String toString(){ rUC@Bf
StringBuilder buff = new StringBuilder FI@!7@
`<I+(8]Uz
(); \B _g=K
buff.append("{"); V=!tZ[4z$h
buff.append("count:").append(count); 'J+dTs;0
buff.append(",p:").append(p); B j!{JcM-^
buff.append(",nump:").append(num); ]Lg$p
buff.append(",results:").append ya7/&Z
)0
g70B22!y
(results); r+8%oWj
buff.append("}"); r5ONAa3.
return buff.toString(); WLr\ l29
} 5a
moK7
X}?`G?'
} #h'F6
#7S[Ch}O
ZJev_mj