Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 mZUfn%QXb(
-Qn=|2Mm?
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &
=/
C
XHy.&Vt
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 *x)8fAr
TW^/sx
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 ^S6u<,
z.rh]Zq
。 @ps1Dr4s
1 tR_8lC
分页支持类: C^)*Dsp
Zec <m8~
java代码: 6b!F 1
OnWx#84
w4LScvBg
package com.javaeye.common.util; f}D1|\7
F"N60>>
import java.util.List; ;Q+xKh%
|_G )qp;
publicclass PaginationSupport { RV&^g*;E
cr;g5C
V
publicfinalstaticint PAGESIZE = 30; {$ep7;'d
`f'K@
privateint pageSize = PAGESIZE; o:6@Kw^
dZ _zg<
privateList items; FCkf#
HD N9.5S
privateint totalCount; 07Edfe
6 K-5g/hL
privateint[] indexes = newint[0]; -[qq(E
K6olYG>
privateint startIndex = 0; wd/<
8>2X
f>ZyI{
public PaginationSupport(List items, int ^`<w&I@
q%5eVG
totalCount){ xTGxvGv8
setPageSize(PAGESIZE); smm]6
setTotalCount(totalCount); ]!IVz)<E&
setItems(items); 1@gg uRF:
setStartIndex(0); G7=pBf
} W0=O+0$^
9!><<7TS
public PaginationSupport(List items, int MaD3[4@#
Tz9`uW~Mf
totalCount, int startIndex){ \(">K
setPageSize(PAGESIZE); {Ha8]y
setTotalCount(totalCount); KzQ3.)/q
setItems(items); 3~#h|?
setStartIndex(startIndex);
=~I-]4
} IuZ) [*W
TT9z_Q5~
public PaginationSupport(List items, int {-A^g!jT&
|+$%kJR=
totalCount, int pageSize, int startIndex){ 1jX3ey~
setPageSize(pageSize); 6;
Y0a4Ax
setTotalCount(totalCount); S\CRG>
setItems(items); a" H WGY
setStartIndex(startIndex); Skz|*n|eY
} 76vy5R(.
~y$ !48o
publicList getItems(){ !`mZ0c+
return items; ,E|m.
} $3,ryXp7
d(:3
publicvoid setItems(List items){ ]qB:PtX
this.items = items; *GUAO){'
} Yhp]x
_sy'.Fo
publicint getPageSize(){ oy<WUb9W
return pageSize; B>Wu;a.:L
} 'q * Bdx
:pRpvhm
publicvoid setPageSize(int pageSize){ sK=0Np=`
this.pageSize = pageSize; H\1qI7N C
} KQ[!o!%
=H<0o?8?c
publicint getTotalCount(){ StI1){Wf
return totalCount; a=TG[* s
} ?`[NFqv_]
AfC>Q!-w
publicvoid setTotalCount(int totalCount){ .qA{x bu
if(totalCount > 0){ FWC5&tM
this.totalCount = totalCount; P_u|-~|\
int count = totalCount / f+.T^es
7E!7"2e
a
pageSize; O@iu aeEW
if(totalCount % pageSize > 0) VzJ5.mRQ
count++; kbPE "urR
indexes = newint[count]; 3DaQo0N
for(int i = 0; i < count; i++){ 4Z*U}w)
indexes = pageSize * OUP?p@%]<
gGMWr.!
8
i; NU(AEfF
} 0hZ1rqq8C
}else{ g=T/_
this.totalCount = 0; C[WCg9Av
} _j>;ipTb+
} Y
qcD-K
eh R{X7J
publicint[] getIndexes(){ gN {'UDg
return indexes; 7DlOW1|
} dO7;}>F$n
?r_l8
publicvoid setIndexes(int[] indexes){ K)Zlc0e
this.indexes = indexes; #'4OYY.
} =:+0)t=ao
joul<t-
publicint getStartIndex(){ gh6d&ucQ^
return startIndex; !AJ]j|@VBd
} iqW1#)3'R
$mGvJ*9
publicvoid setStartIndex(int startIndex){ iK{T^vvk
if(totalCount <= 0) %PJhy 2
this.startIndex = 0; ftBq^tC
elseif(startIndex >= totalCount) IaFr&
this.startIndex = indexes ;W:6{9m ze
oVCmI"'
[indexes.length - 1]; [Vf}NF
elseif(startIndex < 0) _7a'r</@
this.startIndex = 0; Q:6VYONN
else{ ESb
]}c:
this.startIndex = indexes tZ2e!<C
D@X+{
[startIndex / pageSize]; /XS&d%y
} E2B>b[
} 7-_vY[)/
`P@- %T
publicint getNextIndex(){ Tp<k<uKD
int nextIndex = getStartIndex() + 8&V_$+ U
x|eeRf|
pageSize; V,%L~dI
if(nextIndex >= totalCount) djT5X
return getStartIndex(); *R% wUi
else 6k?`:QK/sl
return nextIndex; 7m5Co>NkuK
} .I$}KE)
bXM/2Z?6
publicint getPreviousIndex(){ A\te*G0:S
int previousIndex = getStartIndex() - (P6vOo
NE|[o0On
pageSize; VF0dE
if(previousIndex < 0) +pqM ^3t|y
return0; cjULX+h
else [RU
NuO
return previousIndex; /-0'
Qa+*
} TOI4?D]
h7qBp300
} DlE_W+F
@kD8^,( oH
'PdmI<eXQ
@{Py %
抽象业务类 wX1ig
java代码: >Cd9fJ&0gP
iz}sM>^
"PpjoM
~
/** S T8!i`Q$
* Created on 2005-7-12 2pyt&'NJua
*/ <rK=9"$y(t
package com.javaeye.common.business; -.vDF?@G
zXc}W*ymj
import java.io.Serializable; X`20f1c6q>
import java.util.List; Fm j=
't>r
sp+#
import org.hibernate.Criteria; w! q&
import org.hibernate.HibernateException; 2f:Mm'XdB
import org.hibernate.Session; q"aPJ0ni'
import org.hibernate.criterion.DetachedCriteria; <d$A)S};W
import org.hibernate.criterion.Projections; WBppKj_M
import r25Z`X Z
K^i"9D)A
org.springframework.orm.hibernate3.HibernateCallback; VfSGCe
import q/6UK =
]O!s'lC
org.springframework.orm.hibernate3.support.HibernateDaoS Di??Q_$ak
StQ@g
upport; L]zNf71RD
c"Y!$'|Q
import com.javaeye.common.util.PaginationSupport; Mz|L-62
Da,&+fZI!
public abstract class AbstractManager extends s'2Rs^,hN
k0&lu B%
HibernateDaoSupport {
Q&+c.S
,hE/II`-d'
privateboolean cacheQueries = false; Kd{#r/HZ
}V^e7d
privateString queryCacheRegion; <%,'$^'DS
SgSk!lj
publicvoid setCacheQueries(boolean )W9_qmYd"
41;)-(1
cacheQueries){ TU%"jb5
this.cacheQueries = cacheQueries; q,,j',8kq/
} c/$*%J<
k&DGJ5m$.
publicvoid setQueryCacheRegion(String :,C%01bH|l
Zps&[;R$-
queryCacheRegion){ -lp"#^ ;
this.queryCacheRegion = ?Y!U*& 7
RSH/l;ii
queryCacheRegion; OWV/kz5'H
} ?cBO6^
PdM*5g4
publicvoid save(finalObject entity){ /W9
&Ke
getHibernateTemplate().save(entity); rU*q@y
Px
} t,?,F4j
e-!?[Ujv*%
publicvoid persist(finalObject entity){ BQU/Qo DY
getHibernateTemplate().save(entity); _sm;HH7'*
} nhT;b,G.Z
rys<-i(
publicvoid update(finalObject entity){ AgI >
getHibernateTemplate().update(entity); zn[QvY
} `G0*l|m>
g$gS7!u,
publicvoid delete(finalObject entity){ Z%;)@0~f
getHibernateTemplate().delete(entity); Gx;xj0-"
} O99mic
Ge~,[If+
publicObject load(finalClass entity, zg7G^!PU
aL 8Gnqf2
finalSerializable id){ _y-B";Vmm
return getHibernateTemplate().load %6Rp,M9=
0k.v0a7%
(entity, id); Xvq^1Y?
} 4n4j=x]@
6ZTaQPtm
publicObject get(finalClass entity, U%n,XOJ
W7W3DBKtSm
finalSerializable id){ i9y3PP)
return getHibernateTemplate().get Wv NI=>
km}MqBQl
(entity, id); CX.SYr&!R
} v#Sj|47
>.n;mk
publicList findAll(finalClass entity){ To">DOt
return getHibernateTemplate().find("from 0 S2v"(_T
KZW'O
b>[
" + entity.getName()); psu OJ-
} tw-fAMwU
DQMPAj.
publicList findByNamedQuery(finalString
{&0mK"z_
#>"}q3RO
namedQuery){ F G3Sk!O6
return getHibernateTemplate Hw y5G;
KjBOjD'I
().findByNamedQuery(namedQuery); (Hl8U
} >6IXuq
hR!}u}ECd
publicList findByNamedQuery(finalString query, ^DzL$BX
A3z/Bz4]:#
finalObject parameter){ &adY
return getHibernateTemplate W _J&M4
_Q)d+Fl
().findByNamedQuery(query, parameter); z;[gEA+I
} W"dU1]
AvyQ4xim+
publicList findByNamedQuery(finalString query, r)OO&. P@j
Z^{+,$H@
finalObject[] parameters){ qFrt^+@
return getHibernateTemplate VccM=w%*
9LH=3Qt
().findByNamedQuery(query, parameters); T<f2\q8Uo=
} gxI&f
Q! Kn|mnN
publicList find(finalString query){ F%9cS
:
return getHibernateTemplate().find #FEa 5
B*y;>q "{U
(query); ] xb]8]
} %)8d{1at
`b#/[3
publicList find(finalString query, finalObject XO 0>t{G
qx Wgt(Os
parameter){ nDyvX1]
return getHibernateTemplate().find yQ8M >H#J
"|F.'qZrm
(query, parameter); EbG_43SV
} Tku/OG'
-T 2~W!
public PaginationSupport findPageByCriteria _t$lcOT
&aY/eD
(final DetachedCriteria detachedCriteria){ {-o7w0d_
return findPageByCriteria lr`?yn1D(
7X(rLd
6#
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?F)_T
} ]#vWKNv:;
2_Pz^L
public PaginationSupport findPageByCriteria :/>7$)+
BHF{-z
(final DetachedCriteria detachedCriteria, finalint ^Yf3"D?&
J'|=*#
startIndex){ Bh\
[CY
return findPageByCriteria o~Bk0V=
nsZDZ/jx
(detachedCriteria, PaginationSupport.PAGESIZE, (hpTJsZ
?+bTPl;%'
startIndex); pZc9q8j3
} imo'(j7
!}iLO0
public PaginationSupport findPageByCriteria )EhTM-1
FI3sLA
(final DetachedCriteria detachedCriteria, finalint :X3rd|;kc
|hu"5*
pageSize, NFdJb\
finalint startIndex){ !JT<(I2
return(PaginationSupport) ;6DR.2}?>
&Tf=~6
getHibernateTemplate().execute(new HibernateCallback(){ zb@L)%
publicObject doInHibernate /IGrp.}
Q'FX:[@x-S
(Session session)throws HibernateException { 0|WOReskK
Criteria criteria = &@mvw=d
0|],d?-h
detachedCriteria.getExecutableCriteria(session); ZkJY.H-F
int totalCount = ,2=UuW"K
OU0xZ=G
((Integer) criteria.setProjection(Projections.rowCount 5A0KV7N5
wo,""=l
()).uniqueResult()).intValue(); h1Ke$#$6
criteria.setProjection v&t`5-e-A
5O;/ lX!u
(null); jK ?
List items = eLHa9R{)B
Y;a6:>D%cT
criteria.setFirstResult(startIndex).setMaxResults +=n
x|:no
>i><s>=I`
(pageSize).list(); X}65\6
PaginationSupport ps = UiGUaB mF*
TE*> a5C|
new PaginationSupport(items, totalCount, pageSize, R7\{w(`K
,g<>`={kK+
startIndex); % xH>0
return ps; ~2, wI<Nz
} 4YU 1Kr4
}, true); 30gZ_8C>}
} sT;=7L<TA
S 2{ ?W
public List findAllByCriteria(final MkluK=$
l(0&6ENyj
DetachedCriteria detachedCriteria){ T }8r;<P6
return(List) getHibernateTemplate ?kT~)k
PBPJ/puW
().execute(new HibernateCallback(){ >$k4@eg!
publicObject doInHibernate d-A%ZAkE]
R'1vjDuv
(Session session)throws HibernateException { H|(*$!~e
Criteria criteria = X*p:&=o
Og%zf1)aZM
detachedCriteria.getExecutableCriteria(session); #!<+:y'S?
return criteria.list(); S+e-b'++?
} 1W6n[Xg
}, true); U4mh!
} OFPd6,(E
R&-W_v+
public int getCountByCriteria(final c_DB^M!h
$F
/p8AraK
DetachedCriteria detachedCriteria){ WLj_Zo*^x
Integer count = (Integer) 8Vg`;_ -
:,J86#S)
getHibernateTemplate().execute(new HibernateCallback(){ #L1yL<'
publicObject doInHibernate \`<s@U
K\%"RgF@&
(Session session)throws HibernateException { "b+3 &i|
Criteria criteria = \gPNHL*
=tvm=
detachedCriteria.getExecutableCriteria(session); 1J!tcj1(
return 9M-]~.O
`A}{
I}xq
criteria.setProjection(Projections.rowCount ph|2lLZ
Pq_ApUZa
()).uniqueResult(); s-YV_
} >5z`SZf
}, true); B#/~U`t*
return count.intValue(); 5x L,~"
} -iZ js
} b ffml
k3htHCf*G$
Ml_:Q]kl^
{7MgN'4
t)kr/Z*p\
u[% J#S
用户在web层构造查询条件detachedCriteria,和可选的 {10+(Vl
Jut'xA2Dr
startIndex,调用业务bean的相应findByCriteria方法,返回一个 @0x.n\M_
tGy%n[ \
PaginationSupport的实例ps。 cqU/Y_%l'
\=:g$_l
ps.getItems()得到已分页好的结果集 ;U:o'9^9T
ps.getIndexes()得到分页索引的数组 zYl+BM-j,6
ps.getTotalCount()得到总结果数 ]r{#268
ps.getStartIndex()当前分页索引 l9Cy30O6
ps.getNextIndex()下一页索引 &^Q~G>A
ps.getPreviousIndex()上一页索引 /URj$|
:\HN?_?{4
fJ+E46|4
&cv/q$W4
N7|W.(
"i5AAP?_]{
<P)%Ms
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 orN2(:Ct7
FU3IK3}
,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 <8}9s9Nk
qb/!;U_
一下代码重构了。 Y&:\s8C
}jy7,+
我把原本我的做法也提供出来供大家讨论吧: Iw-6Z+ 94
%4g4 C#
首先,为了实现分页查询,我封装了一个Page类: hD~/6bx
java代码: hCx#H eh
ViC76aJ
vf'jz`Z
/*Created on 2005-4-14*/ UgBY
){<
package org.flyware.util.page; mgl'
d
'k) P(H
/** 6Yi,%#
* @author Joa ZkG##Jp\>
* 4w
*/ SodW5v a
publicclass Page { Wh&Z *J
cN(QTbyl6Q
/** imply if the page has previous page */ )9P
privateboolean hasPrePage;
TOP'Bmb
m*WEge*$t
/** imply if the page has next page */ x-P_}}K 79
privateboolean hasNextPage; @n y{.s+
+hYmL
Sq
/** the number of every page */ iDe0 5f1R
privateint everyPage; A}+r;Y8[h
O&1p2!Bk4
/** the total page number */ "e?#c<p7
privateint totalPage; O4+w2'.,
Ki6BPi^
/** the number of current page */
6}ewBAq%
privateint currentPage; /IR5[67
~wV98u-N
/** the begin index of the records by the current X>YOo~yS5
wH5O>4LO
query */ x~I1(l7r
privateint beginIndex; VY26Cf"
NQ{Z
gnK!"!nL
/** The default constructor */ IBHG1<3
public Page(){ Tl{r D(D
)4O`%9=M&
} MjosA R
:)S4MoG
/** construct the page by everyPage y3$\ m
* @param everyPage ZI*A0_;L
* */ `9)2nkJk'z
public Page(int everyPage){
Rf$6}F
this.everyPage = everyPage; eHZl-|-
} ~w%+y
v\T1,Z@N^
/** The whole constructor */ \YyU5f7';
public Page(boolean hasPrePage, boolean hasNextPage, %=>xzP(z
U-:Z^+Y
YS6az0ie
int everyPage, int totalPage, MA QY/s~F
int currentPage, int beginIndex){ DxG'/5jQ[
this.hasPrePage = hasPrePage; Y\F H4}\S
this.hasNextPage = hasNextPage; ijSYQ
this.everyPage = everyPage; Vc<n6
this.totalPage = totalPage; <GlV!y
this.currentPage = currentPage; H`..)zL|
this.beginIndex = beginIndex; ,l"2MXD
} %6?}gc_
;qQzF
/** e 2&i
* @return KAaeaiD
* Returns the beginIndex. `qEm5+`
*/ DEuW' .o>
publicint getBeginIndex(){ ImW~Jy
return beginIndex; UeTp,
} ?=Qg
clV/i&]Qa
/** k18V4ATE]
* @param beginIndex vK/Z9wR*05
* The beginIndex to set. WWzns[$f
*/ oMf h|B
publicvoid setBeginIndex(int beginIndex){ l$@lk?dc
this.beginIndex = beginIndex; 1a4 $.
{
} !0_Y@>2
q&x#S_!
/** "lAS
<dq
* @return FV,SA3
* Returns the currentPage. LB0=V0|
*/ 2)]*re)
publicint getCurrentPage(){ [^P2Kn
return currentPage; iIRigW
} !7|9r$
BE;iC.rW
/** ou4?`JF)-
* @param currentPage 1@Gv`{v
* The currentPage to set. <\NXCUqDpo
*/ $^GnY7$!>
publicvoid setCurrentPage(int currentPage){ 8`<GplO
this.currentPage = currentPage; :RG6gvz
} p8bTR!rvz
TR7TF]itb
/** $l0w {m!P
* @return EPfVS
* Returns the everyPage. ,\"gN5[$(
*/ /d;l:
publicint getEveryPage(){ ~0:c{v;4
return everyPage; n\,W:G9AR7
} X ^)5O>>|t
Ue%5
:Sdr
/** ]>j_
Y,
* @param everyPage -': tpJk
* The everyPage to set. QJ'C?hn
*/ KO7cZME
publicvoid setEveryPage(int everyPage){ J>&GP#7}
this.everyPage = everyPage; J]e&z5c
} 2j|Eh
".=EAXVU
/** S d -+a
* @return *8+YR
* Returns the hasNextPage. ru
Lcu]
*/ }Qo8Xps
publicboolean getHasNextPage(){ b?,y%D)'
return hasNextPage; AG%aH=TKp
} ^\;5O(9
UNHHzTsr?
/** YTA&G
* @param hasNextPage "Y6mM_flq
* The hasNextPage to set. p5ihuV,
*/ Qmn5-yiw1d
publicvoid setHasNextPage(boolean hasNextPage){ >Li?@+Zl
this.hasNextPage = hasNextPage; -tJ*F!w6U
} Z]CH8GS~<
~I74'
/** :}-[%LSV
* @return nz+KA\iW
* Returns the hasPrePage. eA_4,"{
*/ 4v7RX
publicboolean getHasPrePage(){ ujedvw;sO
return hasPrePage; ^}#!?"Y
} KYaf7qy]
D=$<Ex^p
/** W1z5|-T
* @param hasPrePage 8B5%IgA
* The hasPrePage to set. J!>oC_0]8
*/ !h~\YE)
publicvoid setHasPrePage(boolean hasPrePage){ d29HEu
this.hasPrePage = hasPrePage; {DR+sE
} 3lqhjA
X"sN~Q.0
/** TM;)[R@
* @return Returns the totalPage. WfVie6
* Z^3Risi
*/ dLq!t@?iu>
publicint getTotalPage(){ -1:asM7
return totalPage; W\ckt]'
} /r6DPR0\
J^T66}r[f,
/** *W
l{2&
* @param totalPage L
$~Id
* The totalPage to set. `y(3:##p
*/ YDwns
publicvoid setTotalPage(int totalPage){
+gkB
this.totalPage = totalPage; g`1i[Iu2
} N C&1l]
4$rO,W/&0
} =/;(qy9.-R
Q\Eq(2p
@{G(.S
l;ugrAo?
!ibp/:x
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 e;$s{CNo
xnTky1zq
个PageUtil,负责对Page对象进行构造: N
Jf''e3
java代码: *MNY1+RJ
C*$/J\6xy
>4c 1VEi
/*Created on 2005-4-14*/ 4^r}&9C~
package org.flyware.util.page; ME.LS2'n
}z[se)s
import org.apache.commons.logging.Log; Ic*Q(X
import org.apache.commons.logging.LogFactory; Hs9uDGWp
R B!g,u
/** Gu-Sv!4p
* @author Joa *,(`%b[
* NNT9\JRv_
*/ C^a~)r.h
publicclass PageUtil { MB)xL-j O
2WoB ;=
privatestaticfinal Log logger = LogFactory.getLog Ok@5`?08
R*U>T$
(PageUtil.class); RK,~mXA
Z7Kc`9.0|
/** 5R4 dN=L*1
* Use the origin page to create a new page ZO,]h9?4
* @param page _Cs.%R!r
* @param totalRecords +hfl.OBy
* @return ;O CYx[|
*/ G8SJ<\?
publicstatic Page createPage(Page page, int cG<?AR?wDT
GZ1>]HB>r^
totalRecords){ ^l9S5
{
return createPage(page.getEveryPage(), <MYD`,$yu
q&vr;fB2
page.getCurrentPage(), totalRecords); pJmn;XbME
} \%)p7PNY
ojaZC,}
/** {0|^F!1z
* the basic page utils not including exception w/UsEIr
+mY(6|1
handler p(Sfw>t(
* @param everyPage lr1i DwZV
* @param currentPage [W2k#-%G
* @param totalRecords .hvIq
.vr
* @return page >7n(*M
*/ vXc<#X9
publicstatic Page createPage(int everyPage, int N;htKcZ
pCq{F*;
currentPage, int totalRecords){ )XD_Yq@E
everyPage = getEveryPage(everyPage); )Z62xK2
currentPage = getCurrentPage(currentPage); 9]Y@eRI<
int beginIndex = getBeginIndex(everyPage, UZyo:*yB
O_E[FE:+
currentPage); {AZW."?
int totalPage = getTotalPage(everyPage, az w8BK
51~:t[N|
totalRecords); @~"0|,6VC
boolean hasNextPage = hasNextPage(currentPage, /as1
P^
a$?
totalPage); 4`i_ 4&TS
boolean hasPrePage = hasPrePage(currentPage); 3h4>edM
&ha39&I
returnnew Page(hasPrePage, hasNextPage, UW\.!TV
everyPage, totalPage, 'p<(6*,"
currentPage, yPL@uCzA@
$zJ.4NA
beginIndex); )msqt!Ev
} :5ji.g* 0
:wIbKs.r
privatestaticint getEveryPage(int everyPage){ G,J$lTX
return everyPage == 0 ? 10 : everyPage; ;&iQNXL
} RsE+\)
y'(;!5w
privatestaticint getCurrentPage(int currentPage){ K\uR=L7
return currentPage == 0 ? 1 : currentPage; FsD}Nk=m~
} !4|7U\;
HH>]"mv
privatestaticint getBeginIndex(int everyPage, int /@0wbA
.6r&<*
currentPage){ U:_&aY_
return(currentPage - 1) * everyPage; :Bl $c,J
} 5RqkAC
V97Eb>@
privatestaticint getTotalPage(int everyPage, int SA'
zy45
hse$M\5
totalRecords){ Up8#Nz
T
int totalPage = 0; 5{{u #W%=
MgA6/k
if(totalRecords % everyPage == 0) u{HB5QqK
totalPage = totalRecords / everyPage; 4-sUy
else m#Rll[
totalPage = totalRecords / everyPage + 1 ; O4 [[9
*vht</?J
return totalPage; sI#K01;"
} cBU>/
zIp
ucyxvhH^-
privatestaticboolean hasPrePage(int currentPage){ 0rF{"HM~
return currentPage == 1 ? false : true; x6m21DW w
} kYx|`-PA<r
0nBAO
privatestaticboolean hasNextPage(int currentPage, zg[ksny
d]CRvzW
int totalPage){ J3C"W794}
return currentPage == totalPage || totalPage == -V(5U!^B
3HWI;
0 ? false : true; E:#VS~
} Bisht%]^
k{uc%6s
V0"UFy?i
} JWC{ "6
!YCYmxw#
B|#"dhT
;l"z4>kt7
^IY1^x
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。 ._#|h5
p^NYJV
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 UDhW Y.`'~
5X'[{'i,
做法如下: #k*e>d$
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 '\P6NszY~
*joM[ML` 6
的信息,和一个结果集List: iN<Tn8-YH6
java代码: a>6!?:Rj
)/UPDdO
FSC74N/
/*Created on 2005-6-13*/ s@Y0"
package com.adt.bo; a,!c6'QE
1jO/"d.8n
import java.util.List; Za5*HCo
Gw$U0 HA[,
import org.flyware.util.page.Page; o^biO!4,
0fwo8NgX
/** T-uI CMEf
* @author Joa 5_#wOz0u$
*/ Y ~xcJH
publicclass Result { c=h{^![$
l\JoWL
private Page page; )FYz*:f>&
NbSkauF~b
private List content; X^7bOFWE
eE+zL~CE
/** 4cl}ouG
* The default constructor ]&jXD=a"
*/ S!0<aFh
public Result(){ ==~X8k|{E
super(); 9H`Q
|7g(5
} gM '_1zs
U
[YLaRr
/** ['Hl$2 j
* The constructor using fields 0PjWfM8%
* k& 2U&
* @param page -$>R;L
* @param content LY-fp+
*/ ?l
&S:`
L
public Result(Page page, List content){ p$0G EYwM
this.page = page; IR(qjm\V
this.content = content; km|;T!
} ] K3^0S/
TW"
TgOfd
/** n>"0y^v
* @return Returns the content. 5(]=?$$*t
*/ mR)Xq=
publicList getContent(){ VE`5bD+%e
return content; Ys|tGU
} .i)
H1sD
z1{kZk
/** N`h, 2!(j
* @return Returns the page.
:?S1#d_
*/ V>>"nf,YO
public Page getPage(){ ,6uON@
return page; |@`F!bnLr
} d,tGW
%wzDBsX
/** W1dpKv
* @param content ycz6-kEp
* The content to set. )"`(+Ku&c
*/ G~5EAeG
public void setContent(List content){ {N42z0c
this.content = content; 0Ihp`QGU:
} [+\=x[q
6vAq&Y{JB'
/** l 8qCg/ew
* @param page O~?H\2S
* The page to set. 1t w>C\
*/ &mXJL3iN
publicvoid setPage(Page page){ z~\a]MB
this.page = page; Z?ZiK1) K
} Up*1j:_O
} ND $m|V-C
I|8'#QX
Wn6~x2 LaV
aDceOhfx
6O"?wN%$
2. 编写业务逻辑接口,并实现它(UserManager, jM]B\cvN
h8B:}_Cu
UserManagerImpl) _IYd^c
java代码: -}#=L@
Jh`Pq,B:
dCc"Qr[k
/*Created on 2005-7-15*/ T5H[~b|9-
package com.adt.service; T;!: A
BPs|qb-
import net.sf.hibernate.HibernateException; jGy%O3/
R-QSv$
import org.flyware.util.page.Page; Yz7H@Y2i
6Y9F U
import com.adt.bo.Result; a@4
Zx
p)2
!_0
/** }% 2hBl/
* @author Joa WRrCrXP
*/ s2F<H#
publicinterface UserManager { }.*"ezaZw
Jy<hTd*q
public Result listUser(Page page)throws oHh~!#u
11Sflj
HibernateException; ~C M%WvS
w(Jf;[o
} K
?uHAm
),cozN=NM
@ByD=
RBuerap
]+4QsoFNt
java代码: VgGMlDl
^EtBo7^t
v<0\+}T1R
/*Created on 2005-7-15*/ 5>CmWMQ
package com.adt.service.impl; (B+CI%=
D
Q+bZZMK5,U
import java.util.List; "-
2HKs
WX~:Y,l+u
import net.sf.hibernate.HibernateException; ]]Bqte
l$_q#Kd
import org.flyware.util.page.Page; OeMI
import org.flyware.util.page.PageUtil; vX?MB
P'}WmE'B}F
import com.adt.bo.Result; 2:[
-
import com.adt.dao.UserDAO; J:D{5sE<|
import com.adt.exception.ObjectNotFoundException; [7Fx#o=da
import com.adt.service.UserManager; r{LrQ
}`fFzb
/** 96ydcJY0'
* @author Joa @~p;.=1]F
*/ y-#{v.|L
publicclass UserManagerImpl implements UserManager { k]>1@t
WzinEo{f
private UserDAO userDAO; 1F|e/h%^
dlv1liSXL5
/** &,*G}6wa;&
* @param userDAO The userDAO to set. Q+<{2oVz
*/ <[l0zE5Z8'
publicvoid setUserDAO(UserDAO userDAO){ qe/dWJBa
this.userDAO = userDAO; LOO<)XFJ
} {^8->V
WR|n> i@m
/* (non-Javadoc) bv:M
zYS
* @see com.adt.service.UserManager#listUser LI~ofCp
78~;j1^6u
(org.flyware.util.page.Page) J^w!?nk
*/ <ztcCRov
public Result listUser(Page page)throws \|@u)n_
<Pn]{N
HibernateException, ObjectNotFoundException { WMi$ATq
int totalRecords = userDAO.getUserCount(); >PbB /->
if(totalRecords == 0) ~SzHIVj:6
throw new ObjectNotFoundException Nh^
lC
4
*n4P
("userNotExist"); I@/s&$H`l
page = PageUtil.createPage(page, totalRecords); PP*',D3
List users = userDAO.getUserByPage(page); 6 Mc&gnN
returnnew Result(page, users); Ot<vn34mt:
} y/vGt_^;3<
xcHuH-}
} 3aY^6&
L$zB^lSM
1XppC[))
!+EE*-c1c
E\Qm09Dj`<
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 1Zo"Xb
8pXului
询,接下来编写UserDAO的代码: 9cqq"-$G`
3. UserDAO 和 UserDAOImpl: wH0m^?a!3
java代码: '}5Yc,
[`n)2}
k
XG!s+ShFV
/*Created on 2005-7-15*/ :aHLr[%Mz
package com.adt.dao; TC* 78;r
mVsghDESJ)
import java.util.List; ` W}Bc
OF1fS\P<>
import org.flyware.util.page.Page; <$>Jsv
<rn26Gfr
import net.sf.hibernate.HibernateException; CT0 ~
+tCNJ<S@l$
/** S_ER^Pkg
* @author Joa
}K.2
*/ 59MpHkr
publicinterface UserDAO extends BaseDAO { #?_8 *?
V44M=c7E
publicList getUserByName(String name)throws DG-XX.:z
]jRaR~[UN
HibernateException; B:]%Iu|
PZ.q
publicint getUserCount()throws HibernateException; WKvG|YRDq
zL@FN sYVM
publicList getUserByPage(Page page)throws "i^<
H
`^mY*Cb e
HibernateException; BM>'w,$KL
dWi:V7t+
} [/Vi*Z
oYmLJzCf
78UE?) X"
%0Mvd;#[
pd\x^F`sk.
java代码: _`~\zzUZ
ZnNl3MKV
1m4Xl%KS>
/*Created on 2005-7-15*/ t3 rQ5m
package com.adt.dao.impl; GwM(E^AG
2A(?9
R9&h
import java.util.List; YIn
H8Ex
!v\_<8
import org.flyware.util.page.Page; w!--K9
x='T`*HD
import net.sf.hibernate.HibernateException; EQ%,IK/
import net.sf.hibernate.Query; De`p@`+<#~
5H79-QLd
import com.adt.dao.UserDAO; = P@j*ix
|y$8!*S~(
/** | k?r1dj%O
* @author Joa i$gH{wn\`
*/ :G[6c5j|V
public class UserDAOImpl extends BaseDAOHibernateImpl RlUX][)
M" vd/FV
implements UserDAO { 4S1\5C9
E(-@F%Q
/* (non-Javadoc) "n%0L4J
* @see com.adt.dao.UserDAO#getUserByName kNk$[Yfs
BI|YaZa+p
(java.lang.String) 0K'^g0G
*/ ]AB'POa
publicList getUserByName(String name)throws rHpxk
fP8iz `n
HibernateException { rv <_'yj
String querySentence = "FROM user in class T=,A p a
YmPNaL
com.adt.po.User WHERE user.name=:name"; /Bs42uJ3
Query query = getSession().createQuery N9cCfB\`
U["-`:>jfp
(querySentence); C8W4~~1S
query.setParameter("name", name); 9D[Jn}E:
return query.list(); /8Ru O
} 0BrAgv"3a_
$_f"NE}
/* (non-Javadoc) .I %`yhCW
* @see com.adt.dao.UserDAO#getUserCount() E+z"m|G
*/ <44A*ux
publicint getUserCount()throws HibernateException { kHb H{])
int count = 0; *bSxobn
String querySentence = "SELECT count(*) FROM <c.8f;1F
gGE&}EoLU
user in class com.adt.po.User"; "ph<V,lg
Query query = getSession().createQuery +)ba9bJ|
;ZoEqMv
(querySentence); wfQ^3HL
count = ((Integer)query.iterate().next b Od<x
>@
~-f"&@){,
()).intValue(); >K n7A
return count; &>A<{J@VL
} D~b_nFD
Xkp?)x3~X
/* (non-Javadoc) Sp/<%+2(
* @see com.adt.dao.UserDAO#getUserByPage h>"j!|#!s
2Y~nU(
(org.flyware.util.page.Page) EE5mVC&
*/ 0vZ49}mb)
publicList getUserByPage(Page page)throws ;~-M$a
}4
Xe2Zf
HibernateException { )skz_a}]8
String querySentence = "FROM user in class BcxALRWE
"cz'|z`
com.adt.po.User"; n?:%>O s$
Query query = getSession().createQuery VT [TE
-?p4"[
(querySentence); {Jc.49
query.setFirstResult(page.getBeginIndex()) Om_-#S
.setMaxResults(page.getEveryPage()); ;<l#k7 /
return query.list(); >
JV$EY,
} YL&)@h
Q!y%N&
} `8/D$
nArG
I}@
s("\]K
ipC
<p?PpR
vYg>^!Q
至此,一个完整的分页程序完成。前台的只需要调用 n7/>+V+
Hu$y8_Udw
userManager.listUser(page)即可得到一个Page对象和结果集对象 <DZ$"t
kRqe&N e
的综合体,而传入的参数page对象则可以由前台传入,如果用 Ay0.D FL
Z(I=KBI
webwork,甚至可以直接在配置文件中指定。 s63!]LDr
[H@71+_Q
下面给出一个webwork调用示例: ~L4L|q 7
java代码: TPVB{
107
g.pR4Mf=Z
,c,@WQ2:-
/*Created on 2005-6-17*/ k~*%Z!V}C
package com.adt.action.user; .Ta (v3om%
mXs.@u/
import java.util.List; ?$#P
=VK
G|YNShK4=9
import org.apache.commons.logging.Log; |:]}u|O
import org.apache.commons.logging.LogFactory; m5v IS
import org.flyware.util.page.Page; ;;|.qgxc~
4L_)@n}
import com.adt.bo.Result; zbI|3
import com.adt.service.UserService; ZeqsXz
import com.opensymphony.xwork.Action; e2yCWolmTS
:gn&wi
/** {H*
* @author Joa :$*@S=8 O
*/ NfWL3"&X
publicclass ListUser implementsAction{ bTt1y O
F*T$n"^
privatestaticfinal Log logger = LogFactory.getLog ]\y]8v5(
(H8JV1J
(ListUser.class); i1ScXKO
[1nUq!uTm
private UserService userService; Mc&Fj1h5
J7Mbv2D
private Page page; IN75zn*%
Tje(hnN
privateList users; -3u ;U,}
V8#NXUg<!
/* oFGWI#]ts>
* (non-Javadoc) >a&IFi,j
* t.#ara{
* @see com.opensymphony.xwork.Action#execute() '<s54 Cb
*/ {isL<
publicString execute()throwsException{ 2u$rloc$b
Result result = userService.listUser(page); f]_'icP
page = result.getPage(); 0xY</S
users = result.getContent(); p zZ+!d
return SUCCESS; =*R6O,
} _+.JTk
q~^!Ck+#*
/** [{`2FR:Cd
* @return Returns the page. Q'Tg0,,S
*/ mVFo2^%v
public Page getPage(){ BOWBD@y
return page; <_c8F!K)T
} bObsj]
txvo7?Y*4
/** 6bPl(.(3
* @return Returns the users. 0U~*uDU
*/ PW82
Vp.
publicList getUsers(){ dyk(/#*7W
return users; CW2)1%1iz
} +w-J;GLSy
a|jZg
/** oKCv$>Y
* @param page :_tt9J
* The page to set. uXk]
*/ jwUX?`6jX
publicvoid setPage(Page page){ I _gE`N
this.page = page; R1*4
} wSw> UU
6']HmM
/** gJCZ9{Nl
* @param users ;s;3cC!
* The users to set. xW]65iav
*/ xK_oV+
publicvoid setUsers(List users){ XT4Gz|k
this.users = users; VZq~ -$
} TkJ[N4'0
#f<v%
/** u`&lTJgF/O
* @param userService RWGf]V]6
* The userService to set. dOa9D
*/ v+I-*,R
publicvoid setUserService(UserService userService){ Io|Du
this.userService = userService; [F'|KcE3
} 3%hq<
} :PtZKt;~X
dt^h9I2O
fvcS=nRQv
P#,;)HF
*yaS^k\
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, :W5W
@8Y
(0B?OkQ
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 DzQ
l#`G4Vf
么只需要: #fYB4.i~
java代码: Fs].Fa
TN1pg
N0.|Mb"?t
<?xml version="1.0"?> g;v;xlY`N
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork fGO\f;P
^lAM /
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 8;V9%h`P>
tq}45{FH3
1.0.dtd"> 5nUJ9sqA
Ml7
(<J
<xwork> BHf$ %?3z,
__2<v?\
<package name="user" extends="webwork- P RWb6
2ozh!8aL
interceptors"> %IX)+
Lp`
r!+{In+Z
<!-- The default interceptor stack name W*t]
d
wWy;dma#
--> ~Ix2O
<default-interceptor-ref 'gvR?[!t
o87kF!x
name="myDefaultWebStack"/> %VH, (}i
nuXL{tg6
<action name="listUser" 3f] ;y<Km
QYboX~g~p
class="com.adt.action.user.ListUser"> =29IHL3
<param iN[x
*A|h
=9X1 +x
name="page.everyPage">10</param> z@i4
<result $[A\i<#
pYx,*kG:HW
name="success">/user/user_list.jsp</result> NS~;{d\
</action> DK\XC%~m
\xj;{xc
</package> +yp:douERi
Z*ip=FYR
</xwork> 4P&2Z0
"FWx;65CR
Y @p<f5[c
/{\ /e"5
I I+y
WJ25fTsG
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 0RT 8N=B83
du66a+@t
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。 [mA-sl]
A^>@6d $2
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 3R3H+W0{
O\ZC$XF
lL:a}#qxU
N2v/<
(4T0U5jgT
我写的一个用于分页的类,用了泛型了,hoho 5e/YEDP
x,!Dd
java代码: (?fU l$q\
<X:JMj+
x#J9GP.
package com.intokr.util; gSz<K.CT
x9"Cm;H%
import java.util.List; j#1G?MF
lh8QtPe
/** P.'.KZJ:WD
* 用于分页的类<br> X.eOw>.
* 可以用于传递查询的结果也可以用于传送查询的参数<br> h0'*)`;z
* vR!+ 8sy$
* @version 0.01 QQM:[1;RT
* @author cheng kAQ(8xV
*/ "lI-/G
public class Paginator<E> { dU$VRgP/
privateint count = 0; // 总记录数 ; :P4~R
privateint p = 1; // 页编号 m2c'r3 UEu
privateint num = 20; // 每页的记录数 BDB*>y7(
privateList<E> results = null; // 结果 ]YgR
>fH0>W+!
/** Vr1}Zv3K'
* 结果总数 6ZqU:^3
*/ bj
pruJ`=
publicint getCount(){ @>)VQf8s1
return count; -&Z!b!jN
} _MBhwNBxZ
hOY@vm&
publicvoid setCount(int count){ >}+{;d
this.count = count; Q":_\inF
} m/KaWrw/)
BNfj0e 5b
/** V\cbIx(Z^
* 本结果所在的页码,从1开始 <]qNjsdb9"
* 3iCe5VF
* @return Returns the pageNo. S&_03
*/ 'D+xs}\
publicint getP(){ rH3U;K!
return p; ~"#0rPT
} ?veeW6E(
,/\`Rc^n
/** 2d D"^z{
* if(p<=0) p=1 o,*m,Qc
* r&{8/ 5"
* @param p nTeA=0 4
*/ @dWA1tM
publicvoid setP(int p){ * Gg7(cnpw
if(p <= 0) Ew/MSl6}
p = 1; &C9IR,&
this.p = p; AY AU
} FA+HR
6}^x#9\
/** sL$sj|" S
* 每页记录数量 p&(0e,`z/
*/ -9b=-K.y
publicint getNum(){ ;_,jy7lf
return num; 7Qd4L.
} *k{Llq
h`&TDB2
/** Kxsd@^E
* if(num<1) num=1 yu;EL>G_AY
*/ 3:,%>#"
publicvoid setNum(int num){ ^E70$yB^
if(num < 1) <Wn~s=
num = 1; + -<8^y
this.num = num; .>"xp6
} '12m4quO
JHxcHh
/** :Awwt0
* 获得总页数 Z",0 $Gxu
*/ .I`>F/Sjr
publicint getPageNum(){ O*u
return(count - 1) / num + 1; K*@?BE
} 56Wh<i3
$u<;X^
/** 56pj(}eq
* 获得本页的开始编号,为 (p-1)*num+1 G4|C227EO
*/ L4 po1
publicint getStart(){ /@`"&@W'
return(p - 1) * num + 1; G8repY
} w7MRuAJ4
x1@,k=qrd
/** MXA?rjd0
* @return Returns the results. :` SIuu~@
*/ $<-a>~^Tp
publicList<E> getResults(){ OLG)D#m(4/
return results;
,$6si
} 1I2ndt
[J2evi?
public void setResults(List<E> results){ >!fTWdD^
this.results = results; B&MDn']fV/
} D[>:az`
=v3o)lU
public String toString(){ ;6V~yB
StringBuilder buff = new StringBuilder C6>_wl]
/Z2u0jNArP
(); )
gl{ x
buff.append("{"); ug%7}&
buff.append("count:").append(count); \; XJ$~>
buff.append(",p:").append(p); k)+{Y v*
buff.append(",nump:").append(num); 8(? &=>@
buff.append(",results:").append {L$$"r,
Ic3a\FTr\
(results); ^iH[
22b4
buff.append("}"); K"l~bFCZ8
return buff.toString(); Aw7N'0K9UN
} $?ss5:
S
?8753{wk
} PS~_a
YMo8C(
x1~AY/)v