Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 RCLeA=/N@0
61
~upQaR
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 yR.Ong
jlg(drTo
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 CVR3
A'
5rUdv}.
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 gltBC${7wZ
uSBaDYg
。 6\S~P/PkE
Pr,q*_Yy
分页支持类: *HB-QIl
/,Jqmm#s^
java代码: FU<Jp3<%
>i-"<jG
9Lfv^V0
package com.javaeye.common.util; 5nVt[Puw
FNId;
import java.util.List; pFz`}?c0
PE 5G
publicclass PaginationSupport { RY*U"G0#w
y L~W.H
publicfinalstaticint PAGESIZE = 30; 5QO9Q]I#_\
y$R_.KbO
privateint pageSize = PAGESIZE; HiJE}V;Vq
w"&n?L
privateList items; efE.&]
Pd]|:W< E
privateint totalCount;
^L&iR0
mUx+Y ]Ep
privateint[] indexes = newint[0]; zs#@jv$
SOvF[,+
privateint startIndex = 0; qA5r
% +\."eC
public PaginationSupport(List items, int VTHH&$ZNq
(0kK_k'T
totalCount){ KdbHyg<4
setPageSize(PAGESIZE); 42ivT_H
setTotalCount(totalCount); 3%=~)7cF
setItems(items); "`1bA"E
setStartIndex(0); R0
} }|5Pr(I
4#hSJ(~7S
public PaginationSupport(List items, int ?=fyc1
4x[S\,20
totalCount, int startIndex){ .y:U&Rw4
setPageSize(PAGESIZE); $\y'IQ%
setTotalCount(totalCount); )p%E%6p
setItems(items); Q#[9|A9
setStartIndex(startIndex); >Wg hn:^
} fXQNHZ|4
2*#|Nj=^
public PaginationSupport(List items, int ."y1_dDql
Bo%NFB;
totalCount, int pageSize, int startIndex){ o J;$sj
setPageSize(pageSize); ]- QA'Lq
setTotalCount(totalCount); $l&(%\pp
setItems(items); p0<\G
setStartIndex(startIndex); hTi$.y!k
} EG |A_m85
@/-\k*T
publicList getItems(){ l"]}Ts#
return items; Bh]P{H%
} ]+:^W^bs:
,',o'2=!
publicvoid setItems(List items){ F6flIG&h
this.items = items; 7g}w+p>
} r<Kx0`y
)gy!GK
publicint getPageSize(){ QbpFE)TYJ|
return pageSize; D]Xsvv
#
} 55c|O
q;>7*Y&
publicvoid setPageSize(int pageSize){ M} v/tRI
this.pageSize = pageSize; |64~K\X
} YcK|.Mq':
_X"N1,0
publicint getTotalCount(){ K1!j fp
return totalCount; /HRFAqep
} G?/DrnK:
_D(rI#q
publicvoid setTotalCount(int totalCount){ 2u*KM`fa`
if(totalCount > 0){ A#'8X w|
this.totalCount = totalCount; Px`!A EFd[
int count = totalCount / L"Olwwmk
PQ$%H>{
pageSize; ;)^`3`
if(totalCount % pageSize > 0) EV@X*| w
count++; u-G+ j)
indexes = newint[count]; d-r@E3
for(int i = 0; i < count; i++){ 5>N2:9We
indexes = pageSize * D#JL!A%O
@eIJ]p
i; [>5-$Y OT
} t$#jL5
}else{ vJOw]cwq
this.totalCount = 0; xCl1g4N
} dZ0vA\z|
} s
3f-7f<
O]Qd<%V'x
publicint[] getIndexes(){ =\:qo'l
return indexes; s?,Ek
} G`BU=Fi
J B]q
publicvoid setIndexes(int[] indexes){ iaE^a^*
this.indexes = indexes; zz4N5["
} ktBj|-'>
ZO$m["|
publicint getStartIndex(){ 91-o}|3v
return startIndex; I5n^,@md
} $jqq
`n_
UH-*(MfB
publicvoid setStartIndex(int startIndex){ @{tz:f
if(totalCount <= 0) F Yzi~L
this.startIndex = 0; 3!oi +_
elseif(startIndex >= totalCount) dD|OSB7I7
this.startIndex = indexes ^pF&`2eD
hD*SpVIU
[indexes.length - 1]; YhE+W
elseif(startIndex < 0) WE.{p>
this.startIndex = 0; ll.N^y;a
else{ Jx7C'~,J
this.startIndex = indexes H0`]V6+<f
-0{r>,&Mm
[startIndex / pageSize]; #S*/bao#
} |\IN.W[EL
} K<Iv:5-2
4\u1TYR
publicint getNextIndex(){ "x*egI
int nextIndex = getStartIndex() + PV\+P6aIb
^^as'Dk
pageSize; }Nm#q@o$P
if(nextIndex >= totalCount) jiS_G%G
return getStartIndex(); fc-iAj
else ]J$eDbaEjT
return nextIndex; >\=3:gb:
} "wnzo,
h"_;IUZ!
publicint getPreviousIndex(){ yt=3sq
int previousIndex = getStartIndex() - 7gvnl~C(
92x(u%~E
pageSize; hYNY"VB
if(previousIndex < 0) 3|4|*6
return0; VE{3} S
else EGzzHIZ`!
return previousIndex; (b~T]3Es
} 6ZG+ZHUC&
[] `&vWZ
} _'>oXQJ
``Dq
s!c`=
9c#+qH
抽象业务类 pU%n]]qF
java代码: p~^D\jR.
'H&2HXw&2
XJ` ]ga
/**
(SDr!!V<
* Created on 2005-7-12 9~mh@Kgv
*/ JedmaY06=
package com.javaeye.common.business; L>9V&\
8WbgSY`
import java.io.Serializable; &d+Kg0 :
import java.util.List; 0y;*Cfi9
uRRQyZ
import org.hibernate.Criteria; Nj
xoTLI
import org.hibernate.HibernateException; Ba*,-i3ZK
import org.hibernate.Session; m4&h>9. 8
import org.hibernate.criterion.DetachedCriteria; gL[yA?GoM
import org.hibernate.criterion.Projections; !GLz)#SBl
import ,)Ju [
9N<<{rQ,F
org.springframework.orm.hibernate3.HibernateCallback; 6) -X
import 57zSu3v4Y
[los dnH^?
org.springframework.orm.hibernate3.support.HibernateDaoS -o[x2u~n\
=;3Sx::=
upport; 7/ysVWt
PMh^(j[
import com.javaeye.common.util.PaginationSupport; m-*i>4;
];a=Pn-:}G
public abstract class AbstractManager extends l@ H
@}OL9Ch
HibernateDaoSupport { EB=-H#
jN>{'TqW4
privateboolean cacheQueries = false; D@|W<i-
jR22t`4
privateString queryCacheRegion; ^ZhG>L*
fA<[f
publicvoid setCacheQueries(boolean (m.ob+D
8a="/J
cacheQueries){ XKttZOiGT
this.cacheQueries = cacheQueries; i;jw\ed
} QM
O!v;
QP)pgAc
publicvoid setQueryCacheRegion(String %Nhx;{
,TPISs
queryCacheRegion){ g[Ib,la_a
this.queryCacheRegion = ang~<
Xr2ou5zAn
queryCacheRegion; .DR<Te
} C>$E%=h+_
LbG_ z =A
publicvoid save(finalObject entity){ J'fQW<T4wU
getHibernateTemplate().save(entity); jbu8~\"
} 8p9bCE>\
e~@[18
publicvoid persist(finalObject entity){ 'fF;(?
getHibernateTemplate().save(entity); a / #PLP
} S<u-n8bv
=p?WBZT|:
publicvoid update(finalObject entity){ 4EZ9hA9+
getHibernateTemplate().update(entity); n9A7K$ZD@
} "D'B3; uWK
I8/DR z$A
publicvoid delete(finalObject entity){ n;U`m$vL%
getHibernateTemplate().delete(entity); Tekfw
} h0-hT
/D^"X
4!"
publicObject load(finalClass entity, :GW&O /Yo
1_
C]*p
finalSerializable id){ D
<&X_
return getHibernateTemplate().load H5]^
6
HwX
(+u39NQV
(entity, id); J-)
XQDD
} \XM^oE#G
'|*?*6q
publicObject get(finalClass entity, dd%h67J2<
:
G`hm{
finalSerializable id){ DrBUe'RH:M
return getHibernateTemplate().get \ZhfgE8{%
~r$jza~o(
(entity, id); ]Xf% ,iu
} @`Eg(
XC "'Q+
publicList findAll(finalClass entity){ gV`=jAE_
return getHibernateTemplate().find("from [],1lRYI9_
13%t"-@bh
" + entity.getName()); *U$!I?
} ] GTAq
~L_hZso4
publicList findByNamedQuery(finalString ;3@YZM'wt
CQr<N w
namedQuery){ $w0lrh[+
return getHibernateTemplate @qjfZH@
f7~9|w&
().findByNamedQuery(namedQuery); mp?78_I)
} !$Tw^$n
,4,V4 N
publicList findByNamedQuery(finalString query, 0}FOV`n
6"t;gSt4
finalObject parameter){ L%$|^T=%
return getHibernateTemplate jfx8EbQ
g'u?Rn7*J
().findByNamedQuery(query, parameter); {W~q
z^>u4
} pM&YXb?
V8wKAj
Ux
publicList findByNamedQuery(finalString query, jhX[fT1m
@81Vc<dJ
finalObject[] parameters){ <~X >[PK<
return getHibernateTemplate gEhN3(
@]c(V%x
().findByNamedQuery(query, parameters); hj$e|arB
} `^Eae
N2$I}q%
publicList find(finalString query){ E)-r+ <l
return getHibernateTemplate().find }KK Y6D|d>
X3:XTuV
(query); 2gjGeM
} zrv#Xa!O\
^6P3%
publicList find(finalString query, finalObject L9ap(
zT|)uP*
parameter){ 7Irau_
return getHibernateTemplate().find o/
mF#
'K*AV7>E
(query, parameter); OxtOd\0$
} l|+BC
|Uk"
{
public PaginationSupport findPageByCriteria q;D+ai
xc:!cA{V
(final DetachedCriteria detachedCriteria){ -;XKcS7Ue
return findPageByCriteria ~!d/8?!
y}K\%;`[a
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Bo+DJizu
} m8JR@!t7
Ty@=yA17
public PaginationSupport findPageByCriteria ,j ',x\
"ZHtR/;
(final DetachedCriteria detachedCriteria, finalint \[>9UC%
FvuGup`w
startIndex){ bo=ZM9
return findPageByCriteria !.<T"8BUpv
LrV{j?2@
(detachedCriteria, PaginationSupport.PAGESIZE, mNAY%Wn6k
9
ASb>A2~
startIndex); #4h+j%y[H
} p|/j4@-h
[;oCYb$9
public PaginationSupport findPageByCriteria ,chf~-d
dj&}Gedy
(final DetachedCriteria detachedCriteria, finalint ZC4*{
3q:{1rc
pageSize, #Hh^3N
finalint startIndex){ LsGiu9~S
return(PaginationSupport) DtWwGC
0g<K [mPr7
getHibernateTemplate().execute(new HibernateCallback(){ zT* .jv
publicObject doInHibernate +wk`;0s A
V*$L;xbC|
(Session session)throws HibernateException { !b-bP,q
Criteria criteria = Na,_
pA#}-S%
detachedCriteria.getExecutableCriteria(session); (|fm6$
int totalCount = zggB$5
)g@S%Yu
((Integer) criteria.setProjection(Projections.rowCount l0Ti Z
rba;&D;
()).uniqueResult()).intValue(); v !Kw<
fp|
criteria.setProjection 1fL<&G
tAFti+Qb
(null); YIp-Y}6
List items = sK=}E=
>7U>Yh
criteria.setFirstResult(startIndex).setMaxResults j#6|V]l
iG,t_??
(pageSize).list(); \hP=-J [~C
PaginationSupport ps = jN+N(pIi.o
X7|.T0{=x
new PaginationSupport(items, totalCount, pageSize, 6ZqgY1
0gF!!m
startIndex); W;Jx<-#1
return ps; `wTlyS3[
} &Rz,
J]
}, true); npu6E;'l*
} ? {F{;r
6vf\R*D|A
public List findAllByCriteria(final *NSlo^R-[
pY^9l3y^
DetachedCriteria detachedCriteria){ l t]B#, '
return(List) getHibernateTemplate gCVryB@z2
Y"eEkT\
().execute(new HibernateCallback(){ ]yX@'f
publicObject doInHibernate QI!i
#S+Z$DQD
(Session session)throws HibernateException { 7yiJ1K<bIt
Criteria criteria = m^\TUj
4`2$_T$F
detachedCriteria.getExecutableCriteria(session); P8gXCX!>U
return criteria.list(); x@cN3O
} K,}w]b
}, true); .Nx
W=79t
} g.#+z'l
Rh] P8
public int getCountByCriteria(final {R&ZqEo'D
re,.@${H
DetachedCriteria detachedCriteria){ a%J6f$A#
Integer count = (Integer) dyFKxn`,
qG>DTKIU
getHibernateTemplate().execute(new HibernateCallback(){ ;
a/cty0Ch
publicObject doInHibernate jlKGXD)Q[
U06o;s(
(Session session)throws HibernateException { /k"hH\Pp
Criteria criteria = K{}4zuZ
L]2<&%N2
detachedCriteria.getExecutableCriteria(session); \w)?SVp
return 76#.F
*"G 8
criteria.setProjection(Projections.rowCount {%']w
d\XRUO[
()).uniqueResult(); $-@$i`Kf/
} CYB=Uq,
}, true); K:qOoY
return count.intValue(); Ha ZFxh-(
} bEr.nF
} nY) .|\|i
de-0?6
8tWE=8<
i@<~"~>]7
/?zW<QUI
j+748QAhh
用户在web层构造查询条件detachedCriteria,和可选的 bGh0<r7R
%7`d/dgR
startIndex,调用业务bean的相应findByCriteria方法,返回一个 Wm6dQQ;Bj
iWXMKu
PaginationSupport的实例ps。 ^w6eWzI
5urE
ps.getItems()得到已分页好的结果集 Y%vP#>h
ps.getIndexes()得到分页索引的数组 ixOw=!@
ps.getTotalCount()得到总结果数 r2G*!qK*1
ps.getStartIndex()当前分页索引 "jU
ps.getNextIndex()下一页索引 bBE^^9G=Z
ps.getPreviousIndex()上一页索引 }g,X5v?W
z=?0)e(H,
'rV2Bt,
6hbEO-(
C"T ,MH
'}O!2W&Y]%
8SD}nFQ
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 =O^7TrM
R/N<0!HZ
,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 l:tpL(%
ofEqvoi@
一下代码重构了。 {qAu/ixp
'=%i,
我把原本我的做法也提供出来供大家讨论吧: `QCD$=
jCWu\Oe
首先,为了实现分页查询,我封装了一个Page类: R;=6VH
java代码: 6bL"LM`s
lgG8!Ja
.D@/y uV
/*Created on 2005-4-14*/ !yCl(XT
package org.flyware.util.page; 6IF|3@yD
[u\CD sX
/** px&=((Z7>
* @author Joa H*qD: N
* gO{W#%
*/ "X?LAo
publicclass Page { !\w\ ]7ls
M-91
JOt~
/** imply if the page has previous page */ ~M[>m~8
privateboolean hasPrePage; O&P>x#w
ag/u8
/** imply if the page has next page */ OX,F09.C
privateboolean hasNextPage; &kq7gCd
pFH?/D/q
/** the number of every page */ 0N1' $K$\
privateint everyPage; VEo^ :o)r
xDe47&qKM
/** the total page number */ ]EX--d<_`
privateint totalPage; .%hQJ{vf-^
wR1K8b".DC
/** the number of current page */ wG6FS
privateint currentPage; "w1(g=n
XkoW L
/** the begin index of the records by the current ,yi2O]5e>!
vcD'~)G(*
query */ 6Wu*.53
privateint beginIndex; InX{V|CW?
o;'4c
fsb=8>}63}
/** The default constructor */ /op/g]O}
public Page(){ "x.88,T6
c( 8W8R
} k%a?SU<f
x_pMG!2
/** construct the page by everyPage ;op'V6iG
* @param everyPage _PdAN= C3
* */ 1uj05aZh}
public Page(int everyPage){ c; d"XiA
this.everyPage = everyPage; bAdAp W
} up7x)w:
QZ9M{Y/
/** The whole constructor */ vD"_X"v
public Page(boolean hasPrePage, boolean hasNextPage, nvwDx*[qN
J4&XPr9
8Y]}Gb!
int everyPage, int totalPage, kt5YgW
int currentPage, int beginIndex){ $/y%[ .
this.hasPrePage = hasPrePage; 7@\GU].2
this.hasNextPage = hasNextPage; #s/{u
RYQ
this.everyPage = everyPage; hG[4O3jo\
this.totalPage = totalPage; f#2#g%x
this.currentPage = currentPage; /TG|
B Eb
this.beginIndex = beginIndex; -<12~HKK::
} gtl;P_
aSxG|OkKy
/** Ny[s+2?
* @return "Vq@bNtu+
* Returns the beginIndex. y>&VtN{E
*/ )<tzm'Rc
publicint getBeginIndex(){ +&zb^C`J
return beginIndex; !cv6 #:
} =NI.d>kvC
E{?L= ^cU
/** ~|J*E38
* @param beginIndex xBt4~q;#sE
* The beginIndex to set. xg4T` ])
*/ }$&);7(w
publicvoid setBeginIndex(int beginIndex){ [cY?!Qd0
this.beginIndex = beginIndex; T\.7f~3
} W=!F8g|Qz
W=(MsuirO
/** ~m3V]v(q7
* @return @ICejB<
* Returns the currentPage. =k_XKxd
*/ `mWQWx$V!
publicint getCurrentPage(){ 1@s^$fvW
return currentPage; y`T--v3mI
} Y|Nfwqz
a'o}u,e5
/** ,OFq'}q
* @param currentPage w@4t$bd7
* The currentPage to set. oT$(<$&<
*/ jw2_!D
publicvoid setCurrentPage(int currentPage){ v_[)FN"]Y.
this.currentPage = currentPage; F?!};~$=Z
} fB@K'JQG
nA|gQibA
/** hG< a
* @return 0:PH[\Z
* Returns the everyPage. k,yc>3P;U
*/ U`HXsq
p}
publicint getEveryPage(){ /[p?_EX@
return everyPage; #%9oQ6nO
} *tIdp`xT/T
m[//_TFf]
/** ~t1O]aO(
* @param everyPage MLEIx()
* The everyPage to set. d)pz
*/ :%+^}
publicvoid setEveryPage(int everyPage){ Ki&WS<,0Z
this.everyPage = everyPage; `bBfNI?3d*
} mRg ,A\
a)YJ4\Qg[
/** !4DGP28
* @return nEeQL~:
* Returns the hasNextPage. `lH1IA/3
*/ FCUVP,"T
publicboolean getHasNextPage(){ Po2_ 0uX
return hasNextPage; v3=&{}+j.
} ^\Ue7,H-
3Qm
t]q
/** oP 6.t-<dU
* @param hasNextPage {PP ^Rb)
* The hasNextPage to set. FkB6*dm-
*/ G
"c&C
publicvoid setHasNextPage(boolean hasNextPage){ VPq5xSc?
this.hasNextPage = hasNextPage; F}VS)
} dM>j<JC=
Cw9@2E'b
/** "^e}C@
* @return /\oyPD`((
* Returns the hasPrePage. -&f]Xu
*/ EU&6Tg
publicboolean getHasPrePage(){ ]x5(bnWx
return hasPrePage; GgZEg
?@
} {+9^PC_hm;
cQUH %7m
/** QiQ2XW\E
* @param hasPrePage oX=*MEfX
* The hasPrePage to set. v#T?YK
*/ ?[NTw./'7A
publicvoid setHasPrePage(boolean hasPrePage){ )l 4>=y
this.hasPrePage = hasPrePage; w[J
(E
} p4<M|1Z&
n9mM5H47
/** ImT+8pa
* @return Returns the totalPage. rTm>8et
* P?yOLG+)l)
*/ WsK"^"Z
publicint getTotalPage(){ @[[Cs*-
return totalPage; |zRoXO`]-*
} h>mBkJ
{
7><*
9iOW
/** X=*Yzz}
* @param totalPage x3p;H02i\
* The totalPage to set. *cI6&;y
*/ !z"a_
publicvoid setTotalPage(int totalPage){ 3f7t%
this.totalPage = totalPage; }tl8(kjm
} K2cp f
|P[D2R}
} {YxSH%
,_TH@0{
s$+: F$Y0
NL>[8#
lN=m$ J
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 US*<I2ZLh
GFy0R"&d[
个PageUtil,负责对Page对象进行构造: T[8"u<O96
java代码: \V!X& a
qKI4p3&E
Fc{6*wtO
/*Created on 2005-4-14*/ [/#k$-
package org.flyware.util.page; @poMK:
4BUK5)B
import org.apache.commons.logging.Log; iJynR [7
import org.apache.commons.logging.LogFactory; ,&pF:qlF
Pvb+
/** h9)]N&07b
* @author Joa 1_dMe%53
* BW(DaNt^
*/ :n%sU*'T
publicclass PageUtil { "*H'bzK
a_}BTkfHa
privatestaticfinal Log logger = LogFactory.getLog T/spUlWu
D/%b@Ls2ze
(PageUtil.class); IZ(CRKCGBl
"YdDaj</
/** |WwFE|<
* Use the origin page to create a new page dBD4ogo1
* @param page \qK}(xq[
* @param totalRecords +%cr?g
* @return 8d*<Aki?;
*/ *M\i4FO8
publicstatic Page createPage(Page page, int 88+\mX;A#
4'4s EjyA
totalRecords){ w|UKMbRMU]
return createPage(page.getEveryPage(), Kt&$Si
0Ts_"p
page.getCurrentPage(), totalRecords); FO3eg"{N
} Wp~4[f`,
#I{Yf(2Z
/** tRrY)eElS
* the basic page utils not including exception w
_6Y+
1{fwr1b
handler piM11W}|/
* @param everyPage pmpn^ZR
* @param currentPage sR0e&Y
* @param totalRecords qKb-aP-
* @return page !kk %;XSZ
*/ gm%bxr@X~
publicstatic Page createPage(int everyPage, int 3lrZ-k+S{
x#}eC'Q
currentPage, int totalRecords){ 1 0Tg> H
everyPage = getEveryPage(everyPage); Gv2./<{#
currentPage = getCurrentPage(currentPage); PTc\I
int beginIndex = getBeginIndex(everyPage, G<WDyoN=O
@W5hrei
currentPage); a^)4q\E
int totalPage = getTotalPage(everyPage, :tS>D5dz(
@xM!:
totalRecords); d}B_ll#j-
boolean hasNextPage = hasNextPage(currentPage, :$Di.|l@7
,I:m*.q
totalPage); sZP3xh[B
boolean hasPrePage = hasPrePage(currentPage); hZ /
Gy Xs{*
returnnew Page(hasPrePage, hasNextPage, Tk|;5^#H
everyPage, totalPage, .)pRB7O3
currentPage, lIc9,|FL
%Fm;LQa ]
beginIndex); r+.4|u
} x%?*]*W
>b"z`{tE
privatestaticint getEveryPage(int everyPage){ {O,M}0Eg
return everyPage == 0 ? 10 : everyPage;
F3r
} lp%.n= '\
:g:h 0'G
privatestaticint getCurrentPage(int currentPage){ 1AkHig,
return currentPage == 0 ? 1 : currentPage; YM/3VD
} rOf
$Aoqtz d\
privatestaticint getBeginIndex(int everyPage, int F p=Q$J|
YKxA2`3v%
currentPage){ tVh4v#@+
return(currentPage - 1) * everyPage; dcTM02kEh
} R~c vml
o0+BQ&A)s*
privatestaticint getTotalPage(int everyPage, int oX~$'/2v
TdOWdPvYj
totalRecords){ $=QO_t)?
int totalPage = 0; %oKc?'L0
lNeF>zz
if(totalRecords % everyPage == 0) >nW}zkfn
totalPage = totalRecords / everyPage; 7a_n\]t465
else d"`>&8*
totalPage = totalRecords / everyPage + 1 ; +6Fdi*:
&)}:Y!qiu
return totalPage; >xMhA`l
} eeTaF!W
~I^[rP~
privatestaticboolean hasPrePage(int currentPage){ (GOrfr
return currentPage == 1 ? false : true; "?(Fb_}i
} 8PVs!?Nne
W>s9Mp
privatestaticboolean hasNextPage(int currentPage, U;dt-3?=.h
2o}G<7r
int totalPage){ yzzre>F
return currentPage == totalPage || totalPage == 6uE1&-:L
;Sl0kSu
0 ? false : true; Gqb-3ngH
} q@Yt`$VTN
4J2F>m40
GoA>sK
} T@.m^|~
naCI55Wx
z"C(#Y56 x
ij5=f0^4.
DH*|>m&
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ew ,ed U
mqc Z3lsv
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 3Ty{8oUs^
-#M~NbI,
做法如下: T.N7`
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 :=7;P)
Ywq+l]5/p
的信息,和一个结果集List: bjX$idL
java代码: 4J|t}
w3UJw
_ShJ3\,K
/*Created on 2005-6-13*/ /4BXF4ksi,
package com.adt.bo; s(LqhF[N2]
qinQ5 t
import java.util.List; r>@/XYK&\
b<cM[GaV~
import org.flyware.util.page.Page; n.>'&<H>9
\-id[zKb
/** T0)y5
* @author Joa ~}ZX^l&k{P
*/ 1h0ohW
publicclass Result { 'MlC
1HEp
Zpd>' ${4
private Page page; 2Yjysn
Q*{
2
private List content; ,IB)Kk2
I<-"J^2
/** 2~'quA
* The default constructor %K,,Sl_
*/ v@SrEmg
public Result(){ [cs8/Q8+
super(); @(?d0xCg
} L%Hm#eFx
j2n@8sCSO
/** . M$D
* The constructor using fields ts$UC $
* G\AQql(f4
* @param page )fr\V."
* @param content +38P$Koz{r
*/ {<BK@U
public Result(Page page, List content){ ,gD i)]
this.page = page; d7gSkna`5c
this.content = content; |mA*[?ye@
} bJ}+<##
h /Nt92
/** q0<`XDD`
* @return Returns the content. EZW?(%b>H
*/ h2<$L
publicList getContent(){ 4(ZV\}j1
return content; >GRuS\B
} %c{)'X
K.zs;^
/** ,Ou)F;r
* @return Returns the page. EHjhez
*/ !!>G{
public Page getPage(){ bm?TMhC
return page; 1nmWL0
} c:T P7"vG
!IU*Ayg
/** DR=1';63
* @param content @ U|u _S@
* The content to set. PS1~6f"D
*/ Yw
`VL)v(y
public void setContent(List content){ $sJfxh
r
this.content = content; z<*]h^!3
} 'M/&bu r
>fQN"(tf
/** fXj
* @param page \[jItg,+
* The page to set. v$Z1Lh
*/ cxdM!L; `
publicvoid setPage(Page page){ (5
hu
W7v
this.page = page; XPKcF I=
} (
PlNaasV
} `6su_8Hno
sJ=B:3jS0
{D< ?.'
wl9icrR>
LPF?\mf ^4
2. 编写业务逻辑接口,并实现它(UserManager, &9tsk#bA.g
@RW%EXKt
UserManagerImpl) 5 <poN)"
java代码: 2T5ZbXc+x
{\I\4P
[j39A`t7
o
/*Created on 2005-7-15*/ KG@hjO
package com.adt.service; uI/
A_
jRc#>;dN
import net.sf.hibernate.HibernateException; Yw0@O1Cel
^`THV
import org.flyware.util.page.Page; vD t?N9
DK;-2K
import com.adt.bo.Result; g=8e.Y*Fr
?Fu.,srt
/** 5N0H^
* @author Joa g>f394j
*/ $-73}[UA 4
publicinterface UserManager { zT8K})#
x`&W[AA4
public Result listUser(Page page)throws }$jIvb,3?
`^ok5w"oi
HibernateException; J%'|IwA
t[Q\T0E
} AsOI`@FV
~7g6o^A>
SrIynO
F44")fY
#q%/~-Uk
java代码: zF7T5Ge
b._pG(o1
e6Y0G,K
/*Created on 2005-7-15*/ ]h6<o*
package com.adt.service.impl; tEl_A"^e
}<p%PyM
import java.util.List; I]58;|J
L 'y+^L|X
import net.sf.hibernate.HibernateException; %o>1$f]
b.(^CYYQ
import org.flyware.util.page.Page; 7JbrIdDl|
import org.flyware.util.page.PageUtil; =zdRoXBY[b
A7se#"w
import com.adt.bo.Result; kmwFw>#
import com.adt.dao.UserDAO; ~Q5HM
import com.adt.exception.ObjectNotFoundException; QMP:}
import com.adt.service.UserManager; ?uQpt(
lOZZ-
/** f|!zjX`
* @author Joa 7-)KTBFL
*/ ~<-i7uM
publicclass UserManagerImpl implements UserManager { Gwe9<
y
zK v}J
private UserDAO userDAO; }/|1"D
rnUe/HjH
/** t V</x0#
* @param userDAO The userDAO to set. }I"^WCyH
*/ (Q&Z/Fe
publicvoid setUserDAO(UserDAO userDAO){ kq+L63fZ
this.userDAO = userDAO; HUH=Y;
} hz!.|U@,{<
{dDU^7O
/* (non-Javadoc) Q =Z-vTD+
* @see com.adt.service.UserManager#listUser j1)w1WY0@
*=rl<?tX
(org.flyware.util.page.Page) {8eNQ-4I
*/ sqhM[u
k
public Result listUser(Page page)throws }QK-@T@4<
o 0B`~7(
HibernateException, ObjectNotFoundException { gO29:L[t
int totalRecords = userDAO.getUserCount(); \RJ428sxn
if(totalRecords == 0) w5p+Yx=q
throw new ObjectNotFoundException UWz<~Vy
]*).3<Lw
("userNotExist"); #H|]F86 (
page = PageUtil.createPage(page, totalRecords); o&zeOJW
List users = userDAO.getUserByPage(page); #~"jo[
returnnew Result(page, users); iVE+c"c!2&
} kAMt8
%j
yLRT]H
} R b'"09)$
b@Fa|>"_
wNn6".S
wml`3$"cf
s<:J(gD
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q/':<QY
"Mth<%i
询,接下来编写UserDAO的代码: 'j|;M
3. UserDAO 和 UserDAOImpl: MOXDR
java代码: 2!A/]:[F
9!tRM-
."${.BPn~
/*Created on 2005-7-15*/ >354O6
package com.adt.dao; =4G9ev
4
Vx'_fb?wap
import java.util.List; C+_ NG
_("{fJ,A
import org.flyware.util.page.Page; o`G@Je_}x
*x$\5;A
import net.sf.hibernate.HibernateException; rQU;?[y
>#SQDVFf
/** pl5!Ih6
* @author Joa J*.qiUAgW
*/ mhL,:UE
publicinterface UserDAO extends BaseDAO { )tB mSVprl
R4{2+q=0
publicList getUserByName(String name)throws ;L|%H/SH
13Q|p,^R
HibernateException; ^$VOC>>9
WL<Cj_N_{H
publicint getUserCount()throws HibernateException; H13|bM<
2%QY~Ku~
publicList getUserByPage(Page page)throws J?HYN%
}{s<!b
HibernateException; jlItPdCv
_rOKif?5
} !9B)/Xi
YoJN.],gf
OPar"z^EV
qm2
dF"Sz4DY#
java代码: V1M oW;&
k/Z}nz
A#*0mJ8IK
/*Created on 2005-7-15*/ mV6\gR[h
package com.adt.dao.impl; ht` !@B
\xwE4K
import java.util.List; +c?1\{M
kP3'BBd,
import org.flyware.util.page.Page; ):1NeJOFF
to2dkU
import net.sf.hibernate.HibernateException; y8VLFe;
import net.sf.hibernate.Query; wUab)L
;kY'DKL(
import com.adt.dao.UserDAO; !>+YEZ"
b k 30d
/** Z3)1!|#Q
* @author Joa Zj%l (OVq
*/ ,*Jm\u
public class UserDAOImpl extends BaseDAOHibernateImpl 1 %K^(J;
j"hfsA<_I
implements UserDAO { !q mnMY$
t0(1qFi
/* (non-Javadoc) 5^+>*z
* @see com.adt.dao.UserDAO#getUserByName ;CD@RP{$n
gq!|0
(java.lang.String) 1d,;e:=j
*/
hT]\*},
publicList getUserByName(String name)throws X0O@,
8V?O=3<a
HibernateException { HsO4C)/
String querySentence = "FROM user in class B/7c`V
P
>HEV
a
com.adt.po.User WHERE user.name=:name"; va[@XGaC3
Query query = getSession().createQuery )Z2HzjE
NLf6}
(querySentence); LNPwb1)
query.setParameter("name", name); u?r=;:N|y
return query.list(); *H8(G%a!^
}
$ac
VJI?
Ou>L|#=!
/* (non-Javadoc) 0P_qtS
* @see com.adt.dao.UserDAO#getUserCount() ?VmEbl
*/ ]X%T^3%G
publicint getUserCount()throws HibernateException { 9q(*'rAm
int count = 0; \L Gj]mb1
String querySentence = "SELECT count(*) FROM V*U{q%p(
Ey4%N`H-^
user in class com.adt.po.User";
bVaydJ*
Query query = getSession().createQuery gP:mZ7
kdcr*7w
(querySentence); ]lV\D8#
count = ((Integer)query.iterate().next PRa#;Wb
5ELKL#(
()).intValue(); Zl^#U c"
return count; bxLeQWr6
} )2~Iqzc4
U=QfInB
/* (non-Javadoc) Z:j6AF3;
* @see com.adt.dao.UserDAO#getUserByPage b=(?\
'[g@A>xDvW
(org.flyware.util.page.Page) z]:{ruvH
*/ PZ06
_
publicList getUserByPage(Page page)throws KsZd.Rf=@
v0v%+F#>@
HibernateException { x=s=~cu4,
String querySentence = "FROM user in class ruiAEC<Ej
fsRRnD
com.adt.po.User"; f}qR'ognUu
Query query = getSession().createQuery Gpv9~&