Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Fnzv&
rMdOE&5G
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 6Y`eYp5A
mXAX%M U
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 ;Ze}i/l
VNp[J'a>VZ
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 ,1a6u3f,
18zv]v
%
。 dE%rQE7'
?WKFDL'_0j
分页支持类: +YI/(ko=
zw_Xh~4"b
java代码: zr-HL:js
6H53FMqr
}[ld=9p(
package com.javaeye.common.util; {M )Y6\v
sV%<U-X
import java.util.List; 5.q2<a :
|p-, B>p!
publicclass PaginationSupport { to|O]h2*U2
-2{NI.-Xd
publicfinalstaticint PAGESIZE = 30; 9!NL<}]{
%7xx"$P:R
privateint pageSize = PAGESIZE; ;w a-\Z
l#Ipo5=
privateList items; U_K"JOZ
nxS|]
privateint totalCount; )R(kXz=M
wzwEYZN(q
privateint[] indexes = newint[0]; W_Z%CBjcT
@4#q
privateint startIndex = 0; 0r*E$|zZ
onI%Jl sq
public PaginationSupport(List items, int iV58 m
; $i{>mDT
totalCount){ bqWo*>l
setPageSize(PAGESIZE); LPc)-t|p"
setTotalCount(totalCount); @!"w.@Y
setItems(items); {P&{+`sov
setStartIndex(0); iqreIMWz
} TwH%P2)x
=8?y$WE
public PaginationSupport(List items, int ?\"GT] 5D
V|gW%Z,j
totalCount, int startIndex){ >B!E 6ah
setPageSize(PAGESIZE); ,.A@U*j
setTotalCount(totalCount); m9 o{y6_j*
setItems(items); T~8= =Z{[
setStartIndex(startIndex); jhgS@g=@ZC
} iyKAw
6!*be|<&
public PaginationSupport(List items, int ($pN OGH
;|}N\[fk%]
totalCount, int pageSize, int startIndex){ Fku~'30
setPageSize(pageSize); )CJXkzOX
setTotalCount(totalCount); -d1 YG[1|
setItems(items); zl^ %x1G
setStartIndex(startIndex); &kUEnwQ-
} `<2k.aW4e8
Q3[MzIk 4
publicList getItems(){ =(2y$,6g?
return items; )S@e&a|
} b"Hc==`
u1a0w
publicvoid setItems(List items){ "\cDSiD
this.items = items; R/ix,GC
} CT1@J-np
<:/Lap#D^
publicint getPageSize(){ &W+lwEu
return pageSize; ;)$bhNFHx
} >Q3_-yY+
: fMQ,S0
publicvoid setPageSize(int pageSize){ 6B`XHdCq
this.pageSize = pageSize; "jV:L
} <+Eu.K&
m#1>y}
publicint getTotalCount(){ !xk`oW
return totalCount; .8e]-^Z
} Oy
EOb>
P1C{G'cR
publicvoid setTotalCount(int totalCount){ /S2lA>
if(totalCount > 0){ (KxI*
this.totalCount = totalCount; C# zYZ JZ
int count = totalCount / )l?1dR:sP
2 tD{c^
9<
pageSize; VaP9&tWXj
if(totalCount % pageSize > 0) 4PK/8^@7)>
count++; uDD{O~wF,
indexes = newint[count]; f#mNx
for(int i = 0; i < count; i++){ + OKk~GYf
indexes = pageSize * k;/K']4y
>x?x3 #SX
i; J;HYGu:
} I\e/
Bv^
}else{ zUq ^
this.totalCount = 0; qlSI| @CO
} =jv3O.z q
} # dA9v7
*.%z
publicint[] getIndexes(){ X* 4C?v
return indexes; I+2#k\y
}
#zmt x0
$40G$w
publicvoid setIndexes(int[] indexes){ T*o!#E.
this.indexes = indexes;
=&T%Jm}
} d?:KEi-<7
M>qqe! c*
publicint getStartIndex(){ L a>fvm
return startIndex; CWBlDz
} .A6D&-&z
w#6)XR|+,.
publicvoid setStartIndex(int startIndex){ HuT4OGBFpC
if(totalCount <= 0) 5
w-Pq&q
this.startIndex = 0; $8>kk
elseif(startIndex >= totalCount) hgg8r#4q
this.startIndex = indexes ='A VI-go5
<+y%k~("
[indexes.length - 1]; "m#17J_
elseif(startIndex < 0) ;*%3J$T+
this.startIndex = 0; ,J6t
1V
else{ YCl&}/.pA
this.startIndex = indexes >Nam@,hm
ZLDO&}
[startIndex / pageSize]; "DO|B=EejP
} |N5r_V
} ~=GwNo_
P2Jo^WS
publicint getNextIndex(){ RGgePeaw
int nextIndex = getStartIndex() + 8Z|A'M
p!>5}f6
pageSize; <-6f}wN
if(nextIndex >= totalCount) %$Dn);6=
return getStartIndex(); VLPPEV-u
else 2Tp@;[!3
return nextIndex; zMke}2
} FEH+ PKSc
|)VNf.aJZ
publicint getPreviousIndex(){ B>}B{qi|
int previousIndex = getStartIndex() - z:^(#G{
9dVHh?E
pageSize; q nb#~=x^
if(previousIndex < 0) .oS[ DTn5S
return0; &w!(.uDO
else e0<Wed
return previousIndex; u>ZH-nw O
} F MX^k
y(ceEV
} 23d*;ri5
redMlHM
jl>jy6T
0fGt7 "Q
抽象业务类 s%QCdU ]
java代码: tWyl&,3?1
E4$y|Ni"
2=
Y8$-
/** w=_q<1a
* Created on 2005-7-12 }y1r
yeW<
*/ CKnPMvmz
package com.javaeye.common.business; 2T?8{yO7
c(b2f-0!4
import java.io.Serializable; l(Ya,/4
import java.util.List; s
!IvUc7'
8e5imei
import org.hibernate.Criteria; W(}2R>$
import org.hibernate.HibernateException; b*(,W
import org.hibernate.Session; p;qFMzyS9
import org.hibernate.criterion.DetachedCriteria; wpWZn[j
import org.hibernate.criterion.Projections; I`77[
import `_()|; !y
-lqD
org.springframework.orm.hibernate3.HibernateCallback; oI5^.Dr FW
import j[,XJ,5=
5g%D0_e5
org.springframework.orm.hibernate3.support.HibernateDaoS y@@h )P#
IyEfisOK?
upport; &^`[$LtYd
bt*
import com.javaeye.common.util.PaginationSupport; o@ m7@$7
\[G"/]J
public abstract class AbstractManager extends ;qO3m-(d
c|@OD3w2lM
HibernateDaoSupport { f?r{Q
AJ>$`=
privateboolean cacheQueries = false; 'rNLh3
Wf3{z
D~
privateString queryCacheRegion; #_Zkke~{
ef7 BG(
publicvoid setCacheQueries(boolean wV\7
Fh/psd
cacheQueries){ Q\W)}
this.cacheQueries = cacheQueries; foUBMl
} l_s#7 .9$
x~i\*Ox^
publicvoid setQueryCacheRegion(String P2&0bNY
HVdB*QEH
queryCacheRegion){ ^M1jv(
this.queryCacheRegion = Uw]o9 e0S
t7yvd7
queryCacheRegion; Py?e+[cN
} |{ =Jp<}s
K8/jfm
publicvoid save(finalObject entity){ E9b>wP
getHibernateTemplate().save(entity); 1+"d-`'Z2O
} #)#J`s1R
X(O:y^sX}
publicvoid persist(finalObject entity){ T_qM@/f
getHibernateTemplate().save(entity); ]4/C19Fe!
} SQ*%d.1
c'XSs
publicvoid update(finalObject entity){ xU2i&il^!
getHibernateTemplate().update(entity); .+mP#<mAg
} odDVdVx0
guVuO
publicvoid delete(finalObject entity){ yf[1?{iVo
getHibernateTemplate().delete(entity); beBv|kI4
} iMv):1p>8
D^xg2D
publicObject load(finalClass entity, \x<,Ma=D
QL @SE@"
finalSerializable id){ #)m[R5g(
return getHibernateTemplate().load Em4'b1mDX%
XTA:Y7"O
(entity, id); #]QS
} V*r/0|vd
}+}Cl T
publicObject get(finalClass entity, L{GlDoFk
Z<W f/
finalSerializable id){ S'`G7ht
return getHibernateTemplate().get pI.~j]*:{
}
@
[!%hE
(entity, id); G*=&yx."E
} KzX)6|g{"
i03=Af3
publicList findAll(finalClass entity){ mq}UUk@
return getHibernateTemplate().find("from uP$i2Cy
c_,pd
" + entity.getName()); d04gmc&*
} %__ @G_M
x?]fHin_
publicList findByNamedQuery(finalString ul
b0B"
mML B?I
namedQuery){ '"XVe+.O
return getHibernateTemplate P9R-41!
txm6[Io
().findByNamedQuery(namedQuery); 'f0R/6h\3s
} gV$0J?Pr.
Vx:uqzw#
publicList findByNamedQuery(finalString query, mE=Tj%+x
6kMEm)YjT
finalObject parameter){ 3sRI7g
return getHibernateTemplate V
lkJ$f5l
_dECAk
&b
().findByNamedQuery(query, parameter); |9F-ZH~6
} 4]E1x l
_j4K
publicList findByNamedQuery(finalString query, R6`mmJ+'
9':Hh'
finalObject[] parameters){ _v8u%
return getHibernateTemplate bMsThoePT
5z_Kkf?o
().findByNamedQuery(query, parameters); N"0>)tG
} 4uh~@ Lv
<IBUl}|\
publicList find(finalString query){ *y(UI/c
return getHibernateTemplate().find <;@E
.I\N
[h_d1\ Cr
(query); \rT>&o .i
} -;;m/QM
s0CDp"uJY
publicList find(finalString query, finalObject Z%b1B<u$
]ncK M?'O
parameter){ 6;@:/kl t
return getHibernateTemplate().find YE:5'@Z
J0YNzC4
(query, parameter); \ [M4[Qlq
} "rc QS
H
[w-#
!X2y
public PaginationSupport findPageByCriteria ?!$Dr0r
7<L!" 2VB
(final DetachedCriteria detachedCriteria){ !s !el;G
return findPageByCriteria KNN$+[_;H4
+;*4.}
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ^jcVJpyT@R
} 6JeAXj1g+
qVO,sKQ{
public PaginationSupport findPageByCriteria Ef@)y&hn
O;&5>
W,Z
(final DetachedCriteria detachedCriteria, finalint I.>8p]X
(WP^}V5
startIndex){ c/=\YeR
return findPageByCriteria n
4cos
hQz1zG`z7
(detachedCriteria, PaginationSupport.PAGESIZE, ~0o>B$xJ
IFZw54
startIndex); sO!m,pK(
} ~Y;Z5e=
_;/+8=
public PaginationSupport findPageByCriteria m?1r@!/y
+bR|;b(v
(final DetachedCriteria detachedCriteria, finalint 1. <g C
;>fM?ae5
pageSize, biForT_no
finalint startIndex){ PBcb*7W
return(PaginationSupport) *(XGNp[0
bPkz= ^-
getHibernateTemplate().execute(new HibernateCallback(){ pB]*cd B?
publicObject doInHibernate T1 1>&K)
Q ~n%c7
(Session session)throws HibernateException { _KBa`lhE
Criteria criteria = \/nSRAk
~]9EhC'l
detachedCriteria.getExecutableCriteria(session); cXr_,>k
int totalCount = I"QU{]|J
|+JC'b?,
((Integer) criteria.setProjection(Projections.rowCount ccx0aC3@I
}AiF 7N0
()).uniqueResult()).intValue(); 'geN
dx
criteria.setProjection /%F,
I>6zX
(null); ??LE0i
List items = X`-o0HG
W59 xe&l
criteria.setFirstResult(startIndex).setMaxResults *o!#5c
p;D
{?H/
(pageSize).list(); !/!Fc'A
PaginationSupport ps = E8wkqZN
L$"pk{'
new PaginationSupport(items, totalCount, pageSize, Po.by~|
e?
|4O<@
startIndex); U'Y,T$Q
return ps;
ttt4h
} u6:$AA
}, true); +1\t0P24
} G_WHW(8
fEtBodA)
public List findAllByCriteria(final T{N8 K K
o{l]n*
DetachedCriteria detachedCriteria){ B1%xU?
return(List) getHibernateTemplate 5`i+aH(
EY
c)v6[
().execute(new HibernateCallback(){ tWQ$`<h
publicObject doInHibernate Qw"%Xk
r;>.*60AT
(Session session)throws HibernateException { 10GU2a$0"$
Criteria criteria = =.):tGDp
gO@LJ
detachedCriteria.getExecutableCriteria(session); uu>R)iTQ%S
return criteria.list(); sheCwhV
} }D3hP|.X
}, true); ; 3sjTqD
} 9/I
xh?
Sw? EF8}[
public int getCountByCriteria(final axK/YE7t
[ L
' >
DetachedCriteria detachedCriteria){ 6JRFYgI
Integer count = (Integer) }}"|(2I
ZXIz.GFy+
getHibernateTemplate().execute(new HibernateCallback(){ (B?ZUXM,
publicObject doInHibernate m& D#5C
vTWm_ed+^
(Session session)throws HibernateException { Bo'v!bI7
Criteria criteria = 5aXE^.`
k@gQY _
detachedCriteria.getExecutableCriteria(session); LW9F%?e!>
return gkca{BJ
qagR?)N)u
criteria.setProjection(Projections.rowCount U]9k,#
WZP1g kX&M
()).uniqueResult(); b?,=|H
} KYl!Iw67d
}, true); [8Z
!dj
return count.intValue(); xX Dj4j,
} J: I@kM
} O3#eQs
e5'U[bQm
QHnC(b
j6L (U~%
58eO|c(
9g.5:
用户在web层构造查询条件detachedCriteria,和可选的 H!l9a
wLvM<p7OX
startIndex,调用业务bean的相应findByCriteria方法,返回一个 IABF_GwF
CT'#~~QB
PaginationSupport的实例ps。 XPnHi@x
lB8gD
ps.getItems()得到已分页好的结果集 NK:! U
ps.getIndexes()得到分页索引的数组 eax"AmO
ps.getTotalCount()得到总结果数 HXkXDX9&'.
ps.getStartIndex()当前分页索引 :-(qqC:
ps.getNextIndex()下一页索引 EW+QVu@
ps.getPreviousIndex()上一页索引 >t%@)]*N
.Sv/0&O
@18}'k
#qK5i1<
\: B))y?}d
Q5sJ|]Bc
yW"[}Lh4
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 a zO7C*_
*55unc
,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 b"B:DDw00
-MFePpUt
一下代码重构了。 e_cK#9+
BKgCuz:y
我把原本我的做法也提供出来供大家讨论吧: &)_
z!
I8YCXh
首先,为了实现分页查询,我封装了一个Page类: [X>f;;h
java代码: kdhwnO
|t~>Xs
U~M!T#\s
/*Created on 2005-4-14*/ gP |>gy#e
package org.flyware.util.page; _6g(C_m'T?
s=556
/** Py?Q::
* @author Joa iJCv+p_f
* jvo^I$|2h
*/ ,lFp4 C
publicclass Page { m1xR uj]
'ud[#@2
/** imply if the page has previous page */ #Jr4LQ@A9
privateboolean hasPrePage; QV4FA&f&
4=N(@mS
/** imply if the page has next page */ Yb1Q6[!
privateboolean hasNextPage; a>Zp?*9
g${k8.TV
/** the number of every page */ L^bX[.uZw
privateint everyPage; rZE+B25T~
Lu5X~6j"$
/** the total page number */ o/oLL w
privateint totalPage; w"?RbA
LC\U6J't1
/** the number of current page */ Z9Z\2t
privateint currentPage; MIb[}w=
<d >!%
/** the begin index of the records by the current QX-n l~
{faIyKtW
query */ M+:9U&>
privateint beginIndex; )ybF@emc
~R50-O
z\woTL6D]
/** The default constructor */ {Byh:-e<
public Page(){ 15r=d
{w7/M]m-
} ExeZj8U
E=`/}2
/** construct the page by everyPage c5:X$k\
* @param everyPage Z[eWey_
* */ 2(m#WK7>F
public Page(int everyPage){ sz%_9;`dpL
this.everyPage = everyPage; `3@?)xa
} l,zhBnD
h[Uo6`
/** The whole constructor */ gYe6(l7m
public Page(boolean hasPrePage, boolean hasNextPage, O~Bh(_R&
W!Fc60>p@f
6Rmdf>a
int everyPage, int totalPage, Rz[3cN)?q
int currentPage, int beginIndex){ VKf&}u/
this.hasPrePage = hasPrePage; /'b7q y
this.hasNextPage = hasNextPage; d[XMQX
this.everyPage = everyPage; "\=Phqw
this.totalPage = totalPage; cLw|[!5:
this.currentPage = currentPage; `*D"=5G+
this.beginIndex = beginIndex; Qkhor-f0
} $48Z>ij?f
D3%2O`9
/** 1Kd6tnX
* @return mrr~ #Bb>
* Returns the beginIndex. 1 vtC4`
*/ 8m=O408Q
publicint getBeginIndex(){ f8`dJ5i
return beginIndex; n9n)eI)R
} p@[ fZj
<fV][W
/** yc`*zLWh
* @param beginIndex q6<P\CSHy<
* The beginIndex to set. P,F
eF'J^
*/ -4P `:bF
publicvoid setBeginIndex(int beginIndex){ o{^`Y
this.beginIndex = beginIndex; K Hgn
} d ez4g
]}p<P):hO
/** w~ON861
* @return $2RSYI`py
* Returns the currentPage. lW|v_oP9
*/ Aa4Tq2G
publicint getCurrentPage(){ j4+Px%sW
return currentPage; R<(xWH
} 4 Tw~4b
>[;=c0(
/** $*T?}r>
* @param currentPage >P&1or)e%
* The currentPage to set. 1@Ju sS0^K
*/ PB?2{Cj
publicvoid setCurrentPage(int currentPage){ c&FOt
this.currentPage = currentPage; !a-B=pn!]
} 0!7p5
! Dj2/][
/** Poa&htxe1
* @return py+\e"s
* Returns the everyPage. S(?A3 H
*/ [[zNAq)"
publicint getEveryPage(){ _SJ:|I
return everyPage; u6Lx3
} bI8uw|c
,isjiy
J
/** S#$Kmm
|
* @param everyPage T ~(Sc'8
* The everyPage to set. m}\QGtJ6
*/ aWJj@',_
publicvoid setEveryPage(int everyPage){ p:z~>ca
this.everyPage = everyPage; i7e6l C
} Y#tur`N
y&-QLX L
/** nosD1sS.K8
* @return B4wRwrVI>
* Returns the hasNextPage. [~ 2imS
*/ j49Uj}:j
publicboolean getHasNextPage(){ $LFL4Q
return hasNextPage; %yu =,J j
} $Ery&rX.
ovBmo2W/
/** xLDD;Qm,
* @param hasNextPage g\
vT7x
* The hasNextPage to set. tiHR&v
*/ q$mc{F($D
publicvoid setHasNextPage(boolean hasNextPage){ ]z/R?SM
this.hasNextPage = hasNextPage; $2?j2}M
} fe,6YXUf
=I)43ahd
/** ~~ rR< re
* @return !hhL",
* Returns the hasPrePage. ~rJG4U
*/ |E.BGdS
publicboolean getHasPrePage(){ [nP s
return hasPrePage; /:'>-253
} n2hV}t9O
>( [,yMIY
/** 3m`>D
e
* @param hasPrePage ~IS8DW$;
* The hasPrePage to set. fyA-*)oHv
*/ kMMgY?
publicvoid setHasPrePage(boolean hasPrePage){ $i5J}
this.hasPrePage = hasPrePage; W>)0=8#\
} mpMAhm:
%kjG[C
/** !W9:)5^X
* @return Returns the totalPage. `+"(GaZ
* y{>f^S<
*/ gJ'pwSA
publicint getTotalPage(){ eY5mwJ0K
return totalPage; Xa?O)Bq.
} ng"=vmu
?(R3%fU
/** Es%f@$0uy
* @param totalPage qul#)HI
* The totalPage to set. dkZe.pv$j
*/ >m,hna]RZ
publicvoid setTotalPage(int totalPage){ U5OX.0
this.totalPage = totalPage; pUb1#=
} ^hmV?a:Y
U`mX
f#D
} bIAE?D
P<<+;']
,0. kg
yJq< &g
y]m:
{
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 AcPLJ!y
Aj4 a-vd.
个PageUtil,负责对Page对象进行构造: `KFEzv
java代码: 8b)WOr6n
At4\D+J{Vs
1x:W 3.
/*Created on 2005-4-14*/ \}s/<Q
package org.flyware.util.page; !i^"3!.l,]
2Lf,~EV
import org.apache.commons.logging.Log; D=TS IJ@
import org.apache.commons.logging.LogFactory; SG&,o=I$
ir_XU/ve
/** a(~Y:v
* @author Joa >+P}S@
* ?K>)bA&l'
*/ <m]0!ii
publicclass PageUtil { IMH4GVr"
$Es\ld
privatestaticfinal Log logger = LogFactory.getLog fRQ,Z
0\P5=hD)K
(PageUtil.class); >.d/@3
'
o$sD9xx
/** .d]/:T
-0
* Use the origin page to create a new page h|CZ~
* @param page oAQQ OtpZN
* @param totalRecords hul,Yd) Z
* @return 6 dRhK+|
*/ %^IQ<
publicstatic Page createPage(Page page, int )8@-
j Q5 F}
totalRecords){ zjQ746<&)i
return createPage(page.getEveryPage(), 73;Y(uh9
Q[biy{(b8
page.getCurrentPage(), totalRecords); L0fe
} .B:ZyTI
K381B5_h
/** -e/}DGL
* the basic page utils not including exception SIJ7Y{\.
pCs3-&rI3
handler FvpU]
* @param everyPage ^l!SIu
* @param currentPage 3%kUj
* @param totalRecords 4>*=q*<V5E
* @return page .|
4P
:r
*/ 4v\HaOk
publicstatic Page createPage(int everyPage, int 9Da{|FyrD
gyw=1q+
currentPage, int totalRecords){ |LZ;2 i
everyPage = getEveryPage(everyPage); eiKY az
currentPage = getCurrentPage(currentPage); 'Qy6m'esW
int beginIndex = getBeginIndex(everyPage, mr\,"S-`
(p-q>@m
currentPage); Kjd3!%4mB
int totalPage = getTotalPage(everyPage, Qr$'Q7
e*7O!Z=O
totalRecords); fEHFlgN3Ap
boolean hasNextPage = hasNextPage(currentPage, &B{zS K$N
Qn*l,Z]US
totalPage); -V/y~/]J
boolean hasPrePage = hasPrePage(currentPage); 7g\v (P
o$*(N
returnnew Page(hasPrePage, hasNextPage, <fvu)
f
everyPage, totalPage, Nw*<e ]uD
currentPage, FEjO}lTK
3W?7hh
beginIndex); 5whW>T
} pU7;!u:c4%
lL)f-8DX
privatestaticint getEveryPage(int everyPage){ \sNgs#{7E7
return everyPage == 0 ? 10 : everyPage; /ox7$|Jyr
} 5Z>a}s_i
Q,3kaR@O
privatestaticint getCurrentPage(int currentPage){ ~
WWhCRq
return currentPage == 0 ? 1 : currentPage; tvI<Why\p
} jJ#D`iog5
g0B] ;Y>(
privatestaticint getBeginIndex(int everyPage, int s2O()u-
ip-X r|Bq
currentPage){ |a{;<a
return(currentPage - 1) * everyPage; Nny*C`uDF
} =XR~I
MB)<@.A0
privatestaticint getTotalPage(int everyPage, int )U %`7(bN
wL0[Slf}
totalRecords){ {`!6w>w0
int totalPage = 0; \3JCFor/
d{S'6*`D
if(totalRecords % everyPage == 0) c4fH/-
totalPage = totalRecords / everyPage; cp`Jep<T
else $${I[2R)
totalPage = totalRecords / everyPage + 1 ; dc)%5fV\
7{m>W!
return totalPage; 3``JrkPI
} 5#.m'a)
Jt8;ddz
privatestaticboolean hasPrePage(int currentPage){ \s)MNs
return currentPage == 1 ? false : true; pJHdY)Cz
} UIAazDyC
vbid>$%
privatestaticboolean hasNextPage(int currentPage, I$;`^z
l
U/Xi
int totalPage){ IC
cr
return currentPage == totalPage || totalPage == cGV%=N^BE<
KQfWpHwfj
0 ? false : true; )>ZT{eF
} $g>bp<9v4
]o] VS
Lz 1.+:Ag
} Qt.*Z;Gs
s5*4<VxQN.
`%Ih'(ne
VIAq$iu7
EH844k8
p
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。 mjD^iu8?
x=DxD&I!J
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 Bp^LLH
_lv{ 8vf1B
做法如下: z*},N$2=
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 fpf]qQ
W~7
YiZk|K_
的信息,和一个结果集List: m9[ 7"I
java代码: nah?V"
?Y
,WyEwc]
p/Ul[7A4e
/*Created on 2005-6-13*/ KU8,8:yY
package com.adt.bo; @aS)=|Ls\
0F)v9EK(W4
import java.util.List; sC3Vj(d!i
|=q~X}DA
import org.flyware.util.page.Page; M(C">L]8
);!ND%
/** \TP$2i%W
* @author Joa Q:P)g#suc
*/ %6Gg&Y$j!
publicclass Result { _HwA%=>7
c6:uM1V{
private Page page; IHEbT
XUP{]w`.Z
private List content; r?DCR\Jq
'l'3&.{Yfk
/** :ts3_-cr
* The default constructor O\<zQ2m
*/ )BJkHED{
public Result(){ 6:8s,a3&[k
super(); GN_L"|#)=
} FAM{p=t]HT
Au2?f~#Fv
/** Htgo=7!?\3
* The constructor using fields 9^/Y7Wp/@
* `KZV@t
* @param page N:lE{IvRJ
* @param content ,V1"Typ#<
*/ wNmpUO ?
public Result(Page page, List content){ ]gBnzh.
this.page = page;
Ek<Qz5)
this.content = content; v]SxZLa
} )WoH>D
Z#.d7B"
/** Fip
5vrD
* @return Returns the content. ^SpQtW118
*/ 1]/;qNEv
publicList getContent(){ iZNS? ^U
return content; Mxl;Im]!`.
} :)lS9<Y}
]T)N{"&N/
/** HO<|EH~lu
* @return Returns the page. 1'f_C<.0
*/ |:C0_`M9
public Page getPage(){ s)WA9PiC
return page; ~\am%r>
} j
sPavY
i8?oe%9l
/** [!)HWgx
* @param content 1J[$f>%n]
* The content to set. $I9&cNPv
*/ Cf(WO-F^
public void setContent(List content){ # `^nmC/F
this.content = content; 1@Jp3wW
} M-t9M~
,P9F*;Dj
/** lrJV"H
* @param page Pm%xX~H
* The page to set. /0\g!29l<
*/ ~u%$ 9IhM
publicvoid setPage(Page page){ 3zB'AG3b
this.page = page; WVR/0l&bU
} a{xJ#_/6
} qy'-'UlIr
zr!7*,
p
*+rfRH]a
},d^y:m
]EHsRd
2. 编写业务逻辑接口,并实现它(UserManager, ?7fqWlB
\:+\H0Bz
UserManagerImpl) :!_l@ =l
java代码: 8gavcsVE[
0U7Gl9~
[~8U],?1
/*Created on 2005-7-15*/ 'd2
:a2C]
package com.adt.service; <TVJ9l
;j9%D`u<
import net.sf.hibernate.HibernateException; *OA(v^@tx7
_>vH%FY
import org.flyware.util.page.Page; @RPQ1da
AZ(zM.y!#_
import com.adt.bo.Result; S`vt\g$ dN
I3 "6"
/** GeJ}myD O
* @author Joa s'yR2JYv
*/ 2Vti|@JYp
publicinterface UserManager { Jk%5Fw0
m}z6Bbis 0
public Result listUser(Page page)throws -F?97&G$
q;[HUyY,
HibernateException; a]*{!V{$i
x_~_/&X5
} z6)N![X
UJ,vE}=_{
oaQW~R`_
f+9WGNpw
E"'u2jEG^
java代码: -Kg.w*\H7/
#M~yt`R~
+\ftSm>
/*Created on 2005-7-15*/ s=:)!M.i
package com.adt.service.impl; -r,v3n
[s$x"Ex
import java.util.List; ?;oJ=.T
MB;rxUbhe3
import net.sf.hibernate.HibernateException; B>1,I'/$.
(W#CDw<ja
import org.flyware.util.page.Page; FaCW +9B
import org.flyware.util.page.PageUtil; )Wle
CS_
<cOjtq,0
import com.adt.bo.Result; VHPqEaR
import com.adt.dao.UserDAO; eGT&&Y
import com.adt.exception.ObjectNotFoundException; kBqgz|jE%
import com.adt.service.UserManager; Ye]K 74M.
lD0a<L3
/** !D F~]&
* @author Joa 6fw7\u
*/ C!:Lk,Z
publicclass UserManagerImpl implements UserManager { j*>Df2z
]*P9=!x|M
private UserDAO userDAO; gHc1_G]
5/Qu5/
/** l@&-be
* @param userDAO The userDAO to set. 0S:&wb
*/ ,y'6vW`%g9
publicvoid setUserDAO(UserDAO userDAO){ +EjXoW7V
this.userDAO = userDAO; C)c*s C5N
} C&Qt*V#,
i#4+l$q
/* (non-Javadoc) f/c&Ya(D~
* @see com.adt.service.UserManager#listUser C$0u-Nx8
bM"?^\a&Q