Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 'z=WJV;Vs
Yp_ L.TTb
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3F5Y#[L`
72hN%l
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 2V6=F[T
Gp0H[-oF
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 X<\E
'v`~
{Y>5 [gp
。 #6< X
^Eu]i
分页支持类: \;al@yC=T
x-wIgo+
java代码: m3Mo2};?
;7id![KI4
[E9V#J89
package com.javaeye.common.util; XILB>o.^3
P}So>P~2
import java.util.List; qJjXN+/D
ws"{Y+L
publicclass PaginationSupport { \!!qzrq
~SI`%^L
publicfinalstaticint PAGESIZE = 30; l;*/F`>c
F.zx]][JV
privateint pageSize = PAGESIZE; HGuU6@~hu
c$Vu/dgx
privateList items; RJpH1XQ
j
G`n|fuv
privateint totalCount; "I[a]T}/
KpHt(>NR
privateint[] indexes = newint[0]; J1i{n7f=@
w_c)iJ
privateint startIndex = 0; L1'PQV
UL9]LEGG
public PaginationSupport(List items, int BZS%p
oXC|q-(C
totalCount){ -^1}J
setPageSize(PAGESIZE); tcDWx:Q
setTotalCount(totalCount); A
-C.Bi;/
setItems(items); F$L2bgQR?'
setStartIndex(0); (`W_ -PI
}
j,DF' h
<x QvS^|[
public PaginationSupport(List items, int KCBA`N8
myq@X(K
totalCount, int startIndex){ 5j8aMnv s
setPageSize(PAGESIZE); cTC -cgp
setTotalCount(totalCount); X8}m
%
setItems(items); A-n@:` n~
setStartIndex(startIndex); s3(mkdXv
} ;mT|0&o>#
oI\Lepl*
public PaginationSupport(List items, int ,6J{-Iu
~Q+E" "
totalCount, int pageSize, int startIndex){ /)%$xi
setPageSize(pageSize); d4ga6N3'
setTotalCount(totalCount); _i3?;Fds
setItems(items); dd+hX$,
setStartIndex(startIndex); c
-sc*.&
} W
u C2LM
_p^?_
publicList getItems(){ A#o ~nC<
return items; o+],L_Ab
} ugu|?z*dI
Ub,5~I+`
publicvoid setItems(List items){ lXT+OJF
this.items = items; x/S:)z%X
} <`Xt?K
vVbBg; {
publicint getPageSize(){ ngt?9i;N
return pageSize; =(==aP
} htuYctu`
3>T2k }
publicvoid setPageSize(int pageSize){ 4)Bk:K
this.pageSize = pageSize; J16t&Ha`
} B>;`$-
Al
MMN"j
publicint getTotalCount(){ .A Dik}o
return totalCount; ,q K'!
} F(;=^w
I^GZ9@UE
publicvoid setTotalCount(int totalCount){ _x` oab0@
if(totalCount > 0){ ,
3&DA
this.totalCount = totalCount; V;LV),R?
int count = totalCount / R:5uZAx
T;M4NGmvd
pageSize; W^,(we
if(totalCount % pageSize > 0) :!QT ,
count++; {9XN\v=$"*
indexes = newint[count]; HkQ rij6
for(int i = 0; i < count; i++){ [BTOs4f
indexes = pageSize * cK1 Fv6V#
D~zk2
i; wBlo2WY
} ` yYYyB[
}else{ mVd%sWD
this.totalCount = 0; h:=W`(n5u
} M nnVk=
} I]-"Tw
o_sb+Vn|
publicint[] getIndexes(){ ^2`*1el
return indexes; gl~9|$ivj>
} zi_0*znw
0TqIRUz "C
publicvoid setIndexes(int[] indexes){ }vEMG-sxX
this.indexes = indexes; f;%=S:3
} BC)1FxsGf
$}JWJ\-]
publicint getStartIndex(){ `PtfPt<{
return startIndex; ROJ=ZYof
} f~?kx41dq
ID~}pEQ
publicvoid setStartIndex(int startIndex){ =<X4LO)C
if(totalCount <= 0) >{{0odBF
this.startIndex = 0; T2_b5j3i
elseif(startIndex >= totalCount) ";Q}Gs}
this.startIndex = indexes 3~\,VO''
' 7H"ezt
[indexes.length - 1]; @5h(bLEP
elseif(startIndex < 0) 8'Iei78Ov
this.startIndex = 0; EvptGM
else{ b/d1(B@
this.startIndex = indexes 7;a
I&f!>y?,Z
[startIndex / pageSize]; D$Ao-6QE
W
} '3=@UBs
} 0*,]`A=
m>f8RBp]'
publicint getNextIndex(){ o|APsQE
int nextIndex = getStartIndex() + ,rX|_4n*
|`pDOd
pageSize; GsoD^mjY
if(nextIndex >= totalCount) S])*LUi
return getStartIndex(); _Mi*Fvj
else 0py29>"t
return nextIndex; )
D5JA`
} s)#TT9BbV
Jo\karpb
publicint getPreviousIndex(){ "%w E>E
int previousIndex = getStartIndex() - ),lE8A{ H
E-deXY
pageSize; X2`n&JE
if(previousIndex < 0) MaZVGrcC
return0; ft$!u-`
else 8{ )N%r
return previousIndex; |(=b
} &kQj)
W$J@|i
} 6('CB|ga
v?l*jr1-2
h#Z~x
5Vr#>W
抽象业务类 C8 y[B1Y
java代码: 2BO"mc<#$
cRWYS[O?-
7>3+]njw
/** %>1C($^
* Created on 2005-7-12 2]E i4%jo
*/ VuuF _y;
package com.javaeye.common.business; HE-ErEtGB
q:mqA$n
import java.io.Serializable; (d['f]S+&
import java.util.List; \^dYmU
:ay`Id_tm
import org.hibernate.Criteria; ]) #?rRw
import org.hibernate.HibernateException; cHJ4[x=
import org.hibernate.Session; Sc:)H2k`$
import org.hibernate.criterion.DetachedCriteria; p+CK+m
import org.hibernate.criterion.Projections; j rg B56LL
import /}S1e P6
ZeH=]G4Zv7
org.springframework.orm.hibernate3.HibernateCallback; B3p79j
import G4%dah 5
a[J_H$6H!
org.springframework.orm.hibernate3.support.HibernateDaoS {w]L'0ES[
V=E5pB`Pr
upport; ^ R3g7 DG
{*X|)nr
import com.javaeye.common.util.PaginationSupport; -ug-rdXV
:MGIp%3
public abstract class AbstractManager extends _+<AxE9\
Mlo:\ST|
HibernateDaoSupport { ~sTn?~
[@0Hmd7
privateboolean cacheQueries = false; -Zqw[2Q4
rfOrh^
privateString queryCacheRegion; \cQ+9e)
_r`(P#Hy
publicvoid setCacheQueries(boolean pEY zB;
_3{8Zg
cacheQueries){ +XAM2uN5_.
this.cacheQueries = cacheQueries; }BiA@n,
} `rpmh7*WV
\7Fp@ .S3
publicvoid setQueryCacheRegion(String wpOM~!9R
64SRW8AH
queryCacheRegion){ *a`_,Q{x
this.queryCacheRegion = &7KX`%K"D
l?KP/0`
queryCacheRegion; A6#v6 iT
} >|hqt8lY
$ ~/x;z:
publicvoid save(finalObject entity){ ^;;gPhhWV
getHibernateTemplate().save(entity); |q 0iX2W
} 8e_9u@p+w
MwWN;_#EO)
publicvoid persist(finalObject entity){ LP}j0)n
getHibernateTemplate().save(entity); '^BTa6W}m
} B &)wJG
2MDY nMy
publicvoid update(finalObject entity){ |w.5*]?H
getHibernateTemplate().update(entity); 2XV3f$, H
} 67 wq8|
.;37 e
publicvoid delete(finalObject entity){
1Pd2%
getHibernateTemplate().delete(entity); t8Giv89{
} #a!qJeWm0
UeaHH]U
publicObject load(finalClass entity, eit %U
(?z"_\^n/
finalSerializable id){ ]Waa7)}DM
return getHibernateTemplate().load y{QF#&lW
8o,"G}Hjk
(entity, id); Uy$?B"Z
} 0|~3\e/QV
?I 7hbqQd
publicObject get(finalClass entity, 86~q pN
<is%lx(GDX
finalSerializable id){ 0vcFX)]yW
return getHibernateTemplate().get ''B}^yKEW
|$c~Jq
(entity, id); M;E$ ]Z9
} vFsl]|<;8
%~qY\>
publicList findAll(finalClass entity){ RGLi#:0_.x
return getHibernateTemplate().find("from .Yxf0y?uv
|3 v+&eVi
" + entity.getName()); <*DP G\6Ma
} NV9H"fI
t+n+_X
publicList findByNamedQuery(finalString =kn-F T
X&.LX
namedQuery){ ]D|Hq4ug
return getHibernateTemplate W.
p'T}2
.$"69[1H
().findByNamedQuery(namedQuery); .0]Odf:@
} ;Y`k-R:E6A
"$|ne[b2
publicList findByNamedQuery(finalString query, Y> PC>
&(rR)cG
finalObject parameter){ D,,
x<JG|
return getHibernateTemplate S$ 91L
t`vIcCXqyl
().findByNamedQuery(query, parameter); 4AuJ1Z
} 3H@29TrJ+
TS;?>J-
publicList findByNamedQuery(finalString query, gR8vF
|=ljN7]!
finalObject[] parameters){ FY <77i
return getHibernateTemplate B e2yS]U
"6o5x&H
().findByNamedQuery(query, parameters); p`{ | [<
} lcEin*Oc
;>B06v
publicList find(finalString query){ Zcxj.F(,
return getHibernateTemplate().find 2^=.jML[
Fx' E"d
(query); a1#
'uS9W
} o|7
h
f)!7/+9>
publicList find(finalString query, finalObject hS+R/7
J1{ucFa
parameter){ {A MoE+U
return getHibernateTemplate().find \o{rw0w0
nwPU{4#l<
(query, parameter); xzTF| Z\
} [49Ae2W`
~F=,)GE
public PaginationSupport findPageByCriteria +~1~f'4J
(&a<6k
(final DetachedCriteria detachedCriteria){ ]
336FgT
return findPageByCriteria U.B=%S
\"u3x.!
(detachedCriteria, PaginationSupport.PAGESIZE, 0); f;"6I
} %Fg}"=f1
0piBK=tE/
public PaginationSupport findPageByCriteria P_w\d/3
,LHQ@/}A C
(final DetachedCriteria detachedCriteria, finalint 6Q6l?!|W4
A|esVUo<3^
startIndex){ ]$vJK
return findPageByCriteria <.h\%&'U
3koXM_4_{)
(detachedCriteria, PaginationSupport.PAGESIZE, v 8`)h<:W?
X}5aE4K/
startIndex); k<M~co;L
} P;dp>jL
s;0eD5b>x
public PaginationSupport findPageByCriteria p~sfd
+H K)A%QI
(final DetachedCriteria detachedCriteria, finalint R;XR?59:.
^3-Wxn9&
pageSize, 7(<49bb.V
finalint startIndex){ yO6
_Gq{
return(PaginationSupport) w$5N6
g1uqsqYt
getHibernateTemplate().execute(new HibernateCallback(){ i~IQlyGr.
publicObject doInHibernate Iy}r'#N
Z`?<A da
(Session session)throws HibernateException { E00zf3Jgv'
Criteria criteria = G=8w9-Ww
(Jw[}&+
detachedCriteria.getExecutableCriteria(session); !_`T8pJ`
int totalCount = FNDLqf!j
%(-YOTDr
((Integer) criteria.setProjection(Projections.rowCount (jD..qMs#
{I|k@
()).uniqueResult()).intValue(); X*~NE\
criteria.setProjection j}R4mh
gkpNT)
(null); *x|
<\_+
List items = 7[-jr;v
0<L@f=i
criteria.setFirstResult(startIndex).setMaxResults x~GV#c
3D~Fu8Hg1
(pageSize).list(); LIH>IpamN
PaginationSupport ps = Q;P ~'
(nrrzOax
new PaginationSupport(items, totalCount, pageSize, Et'C4od s
D,eJR(5I
startIndex); $EJ*x$
return ps;
F!>K8 q
} 4Uf+t?U9
}, true); ](0Vm_es
} J'O`3!Oy/
^@L[0Z`
public List findAllByCriteria(final bT-G<h*M
Wsz='@XvB
DetachedCriteria detachedCriteria){ >`NY[Mn
return(List) getHibernateTemplate ioi
H>XbqIkL@
().execute(new HibernateCallback(){ gSj-~kP
publicObject doInHibernate [/uKo13
&up/`8
(Session session)throws HibernateException { >KY\Bx
Criteria criteria = *gz {:}NX
a`pY&xq::
detachedCriteria.getExecutableCriteria(session); ,f?#i%EF&
return criteria.list(); xYu~}kMu
} Mty]LMK
}, true); h.=B!wKK
} )Elr8XLw
Z `\7B e
public int getCountByCriteria(final f!$J_dz
aJ)5 DlfLR
DetachedCriteria detachedCriteria){ Bhq(bV
Integer count = (Integer) yL
Q&<\
)vU{JY;
getHibernateTemplate().execute(new HibernateCallback(){ ''v1Pv-
publicObject doInHibernate _TPo=}Z
Y|VzeJC
(Session session)throws HibernateException { `u>BtAx8
Criteria criteria = 93WYZNpX
;5|EpoM
detachedCriteria.getExecutableCriteria(session); 5ZKnxEW,(
return }"&(sYQ*`
0KQ8;&a|
criteria.setProjection(Projections.rowCount *i?qOv/=>
YqJIp. Z
()).uniqueResult(); I@S<D"af
} ;ZqFrHI M`
}, true); a;S^<8
return count.intValue(); w%_BX3GTO
} o7T|w~F~R
} Ksp;bfe
ibuI/VDF
B)Q'a3d#
]s -6GT
>Qx#2x+
>ATW/9r
用户在web层构造查询条件detachedCriteria,和可选的 jF;4
8g@^
$"FdS,*qKl
startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;dFe >`~
*@&
"MZ/M
PaginationSupport的实例ps。 =@w:
1}uDgz^
ps.getItems()得到已分页好的结果集 lewDR"0Kx
ps.getIndexes()得到分页索引的数组 9>#|~P&FE
ps.getTotalCount()得到总结果数 \+uqP:Ty
ps.getStartIndex()当前分页索引 0l=}v%D
ps.getNextIndex()下一页索引 =e;wEf%`
ps.getPreviousIndex()上一页索引 qc6IH9i`
K(d!0S
eI}VH BAz
@,MdvR+a
cBI)?
yx2.7h3
C P#79=1
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ]1&9~TL
(OqJet2{+
,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 Ng"vBycy
1,j9(m2
一下代码重构了。 4iz&"~&1
x5SQ+7
我把原本我的做法也提供出来供大家讨论吧: A,{D9-%
$)3PF
首先,为了实现分页查询,我封装了一个Page类: I{zE73
java代码: .e"Qv*[^
5gD)2Q6
5Mr;6
]I<
/*Created on 2005-4-14*/ wP/9z(US
package org.flyware.util.page; zb/Xfu.)?6
&XRFX 5gP
/** y.:-
* @author Joa {0e{!v
* f^4*. ~cB
*/ j#,M@CE
publicclass Page { LH#LBjOZk
Q)BoWd
/** imply if the page has previous page */ 1ckw[ 0d
privateboolean hasPrePage;
_CJr6Evs
%"Q!5qH&
/** imply if the page has next page */ )_e"Nd4
privateboolean hasNextPage; E$tk1SVo
a{HgIQg_>R
/** the number of every page */ ' 1'1T5x~
privateint everyPage; `U_>{p&x
Kw0V4UF
/** the total page number */ 6r=)V$K<
privateint totalPage; k^5Rf
%C6zXiO"
/** the number of current page */ $lAb6e$n
privateint currentPage; UUf1T@-
D2:a
/** the begin index of the records by the current ?VZXJO{^
DgT.Lku?
query */ uAS8F=9xP
privateint beginIndex; Z*(!`,.bB
z!C4>,
p:<gFZb
/** The default constructor */ 8^/Ek<Qb|
public Page(){ a-A+.7
0rJ\e
} \v3>Eo[
,cy/fW
/** construct the page by everyPage QjjJtKz
* @param everyPage ZYR,8 y
* */ ok%a|Zz+]
public Page(int everyPage){ 2@m(XT
(
this.everyPage = everyPage; aU.0dsq
} },EUcVXk
v(@+6#&
/** The whole constructor */ zGL<m0C
public Page(boolean hasPrePage, boolean hasNextPage, b8{h[YJL2
`b#nC[b6|v
<W=[
sWJ
int everyPage, int totalPage, v`+n`DT
int currentPage, int beginIndex){ !OoaE* s
this.hasPrePage = hasPrePage; j&[3Be'pQ
this.hasNextPage = hasNextPage; )'
x/q
this.everyPage = everyPage; AY/-j$5+?
this.totalPage = totalPage; U8QR*"GmT
this.currentPage = currentPage; z)W#&JFF
this.beginIndex = beginIndex; uWR,6\_jY
} <7FP"YU
|Y8Mk2,s
/** 7\0|`{|R@
* @return CdzkMVH
* Returns the beginIndex. {GX
&)c4
*/ Z\*5:a]
publicint getBeginIndex(){ N1+4bR
return beginIndex; ."F'5eTT~
} ,Og[[0g
lNA'M&
/** S4 k^&$;
* @param beginIndex QSn;a 4f
* The beginIndex to set. 7SA-OFM
*/ "S B%02
publicvoid setBeginIndex(int beginIndex){ s`Be#v
this.beginIndex = beginIndex; 3lLW'g&=
} y?Hj%,
C>JekPeM
/** *@ <8&M9x
* @return ,Ou1!`6?t
* Returns the currentPage. &e HM#as
*/ AT%*
~tr
publicint getCurrentPage(){ vR%j#v|s
return currentPage; QLF,/"
} .y %pGi
<4l.s
/** [D<RV3x9
* @param currentPage NRHr6!f>
* The currentPage to set. #uD)0zdw
*/ zqekkR]
publicvoid setCurrentPage(int currentPage){ <K DH
this.currentPage = currentPage; B91S
h`
} q9>Ls-k
*2 qh3
/** Tsm)&$JI8
* @return
^MWEfPt
* Returns the everyPage. GZ/pz+)i&
*/ *}
*!+C3
publicint getEveryPage(){ AkYupP2]v
return everyPage; x38SSzG:L
} TRs[ ~K)n
PtVo7zOye
/** +Fc ET
* @param everyPage )CC?vV
* The everyPage to set. ULp)T`P
*/ avu*>SB
publicvoid setEveryPage(int everyPage){ t7jh?]
this.everyPage = everyPage; Cp .1/
} ntrY =Y
s"I-YFP%c
/** 4o1Q7
* @return \]Y\P~n
* Returns the hasNextPage. azao`z
*/ jGO9n
publicboolean getHasNextPage(){ 9nT?|n]>
return hasNextPage; m.1LxM$8
} BKa A=Bl
4mEzcwo'
/** @+}rEe_(
* @param hasNextPage j4E H2v
* The hasNextPage to set. *0=fT}&!
*/ >]>0KQfO
publicvoid setHasNextPage(boolean hasNextPage){ fC=fJZU7$
this.hasNextPage = hasNextPage; r/UYC"K3
} Jy]FrSm^
6!4';2Q
/** y<O@rD8iA
* @return pp/#Am
* Returns the hasPrePage. Oamv9RyDvC
*/ l'|E,N>X
publicboolean getHasPrePage(){ v*&Uk'4E
return hasPrePage; <\>+~p,
} uQeqnGp
!nec 7
/** N YCj; ,V
* @param hasPrePage gsnP!2cR
* The hasPrePage to set. '
be P
*/ &J\B\`
publicvoid setHasPrePage(boolean hasPrePage){ $8jaapNm@
this.hasPrePage = hasPrePage; _GE=kw;:
} :lgHL3yl
.6\T`6H=a
/** E|Q{]&$;Z"
* @return Returns the totalPage. )V=0IZi
* 66/Z\H^d
*/ DP|TIt ,Rl
publicint getTotalPage(){ 9~=gwP
return totalPage; 64?Pfir6
} Nfr:`$k
z9^c]U U)E
/** /j11,O?72
* @param totalPage |pBMrN+is
* The totalPage to set. FH4u$g+
*/ n;%y
publicvoid setTotalPage(int totalPage){ 3QIdN
this.totalPage = totalPage; 4 ^4d9?c
} S)+CTVVE
RV}GK
L>gn
} q1STRYb
JwjI{,jY
-H`\?
R
4b]_
#7Qm
d`85P+Qen|
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 Tj&'KF8?L
`-o5&>'nf
个PageUtil,负责对Page对象进行构造: o/WC@!wg K
java代码: _$8{;1$T?
`v~!H\q
\9'!"-i
/*Created on 2005-4-14*/ EA6t36|TX
package org.flyware.util.page; ]dq5hkjpU
mGO>""<:
import org.apache.commons.logging.Log; 0potz]}
import org.apache.commons.logging.LogFactory; Gbn4*<N
,7<DGI_y
/** p!}ZdX[u
* @author Joa L@nebT;\'
* []"=]f{1};
*/ Z2#`}GI_m
publicclass PageUtil { +1/b^Ac
Rjq a_hxrS
privatestaticfinal Log logger = LogFactory.getLog H'Ln
P>@n#
z{|LQt6q
(PageUtil.class); v77fQ0w3
9_UN.]
/** -6`;},Yr
* Use the origin page to create a new page \DS^i`o)rY
* @param page 3b@VY'P
* @param totalRecords tFiR!f)
* @return 5,R`@&K3D
*/ 3 z=\.R
publicstatic Page createPage(Page page, int AWT"Y4Ie
R*bmu
totalRecords){ G mA!Mo
return createPage(page.getEveryPage(), Xu6K%]i^
?}8IQxU
page.getCurrentPage(), totalRecords); Bc<n2 C0
} SO3cY#i
z"
"r. .
/** . :a<2sp6
* the basic page utils not including exception Y\(;!o0a
6,+nRiZ
handler +c) TDH
* @param everyPage 5un^yRMB-
* @param currentPage 0hwj\{"
* @param totalRecords +s~.A_7)
* @return page X;VQEDMPU
*/ smup,RNZRX
publicstatic Page createPage(int everyPage, int utH%y\NMF|
uPLErO9Es[
currentPage, int totalRecords){ :YNp8!?T?
everyPage = getEveryPage(everyPage); 74f9|~%
currentPage = getCurrentPage(currentPage); g5Td("&n
int beginIndex = getBeginIndex(everyPage, TzKK;(GX
S4bBafj[I
currentPage); K5`Rk"s
int totalPage = getTotalPage(everyPage, MhxDV d
"U8S81'
totalRecords); OCK>%o$[
boolean hasNextPage = hasNextPage(currentPage, P^i.La,
.~mCXz<x
totalPage); 0+ `Pg
boolean hasPrePage = hasPrePage(currentPage); *||d\peQ
2f,2rW^i
returnnew Page(hasPrePage, hasNextPage, Fo}7hab
everyPage, totalPage, E FY@Y[
currentPage, W)4QOS&
Oy_c
beginIndex); -^SA8y
} Fn+?u
LM"y\q ]
privatestaticint getEveryPage(int everyPage){ v>mn/a
return everyPage == 0 ? 10 : everyPage; Z
cpmquf8L
} _0(7GE13p
926Tl
privatestaticint getCurrentPage(int currentPage){ X?o(
b/F-
return currentPage == 0 ? 1 : currentPage; fn}UBzED\
} T):SGW
ax|1b`XUr"
privatestaticint getBeginIndex(int everyPage, int -F1-
e+=
S$[k Q|Am
currentPage){ 2Z/K(J"&J
return(currentPage - 1) * everyPage; shgAhx
} 'C>U=cE7
uaw <
privatestaticint getTotalPage(int everyPage, int aGoE,5
n&Yk<
totalRecords){ N1x@-/xa|
int totalPage = 0; m,_d^
%y<]Yzv.
if(totalRecords % everyPage == 0) $_X|,v9
totalPage = totalRecords / everyPage; ,)fkr]`<
else ,k0r
totalPage = totalRecords / everyPage + 1 ; ;#k-)m%
:`Az/U[
return totalPage; 5VE2@Fn}
} Y+-xvx
:
"!UVs+)]
privatestaticboolean hasPrePage(int currentPage){ P?ep]
return currentPage == 1 ? false : true; Qt+:4{He
} }e]f
XbXA+ey6
privatestaticboolean hasNextPage(int currentPage, ^TFs;|..
KMK`F{
int totalPage){ \%A%s*1
return currentPage == totalPage || totalPage == C>QIrZu
BavO\{J#|0
0 ? false : true; { T]?o~W
} @QEqB_W
6oL1_)
8E^@yZo{
} 6][1<}8
.ln8|;%
8cxai8
;%!m<S|%k
UlovXb
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 RW7(r/C
2k
-+^}r
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 /SR^C$h'I
HgRwiIt
做法如下: F[`ZqW
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0@=MOGQb
z3?\:Yz
的信息,和一个结果集List: mZvG|P$}
java代码: 6[dur'x
-w6
"?
kODK@w V-
/*Created on 2005-6-13*/ c6AWn>H
package com.adt.bo; 'c`jyn
&xSa7FY
import java.util.List; Qvoqx>2p5
{padD p
import org.flyware.util.page.Page; .p6+l!"
15H6:_+=0
/** 2%UBwSiqR
* @author Joa g@v
s*xE
*/ NX6nQ
publicclass Result { )mcEQ -!b
"5|Lz) =
private Page page; K\.5h4k
|;vi*u
private List content; j|_E$L A\
H#d:kil Ny
/**
j2n,f7hl.
* The default constructor arZ@3]X%a
*/ U]4pA#*{|
public Result(){
u=l1s1>
super(); {bNXedZ\
} ]`=X'fED
j6}R7$JR
/** c'fSu;1
* The constructor using fields P>QpvSd_#
* RMYP"
* @param page f|7u_f
* @param content 9h,u6e
*/ OyG"1F
public Result(Page page, List content){ hZ\+FOx;
this.page = page; )h$NS2B`
this.content = content; Vy)hDa[&
} \k8rxW
U HO_Z
/** alFjc.~}
* @return Returns the content. ZXb0Y2AVx
*/ 2(YPz|~W
publicList getContent(){ \>/M .2
return content; m>&HuHf
} )hKS0`$|
d.<~&.-$
/** <I*x0BM=
* @return Returns the page. P* #8ZMA<
*/ o@E/r.uK
public Page getPage(){
p#d+>7
return page; pb;")Q'
} D@YP7
r8M Zvm2
/** "E!mva*NU
* @param content V1=*z
* The content to set. }qPhx6nP
*/ @!tVr3;N$
public void setContent(List content){ D #2yIec
this.content = content; rjA@U<o
} g9h(sLSF
obClBO)@Y
/** |?m` xO
* @param page Al"3 kRJJ
* The page to set. L wJ0
*/ ilLBCS}
publicvoid setPage(Page page){ 2h~-
this.page = page; %uESrc-;
} ;1AG3P'
} VkmRh,T
iAO5"(>}?
Y0uvT7+[hi
>O`l8tM
dXvt6kF
2. 编写业务逻辑接口,并实现它(UserManager, =J'P.
aC=['a>)
UserManagerImpl) C*Vd -U
java代码: h,t|V}Wb
qojXrSb"y
T`YwJ6N
/*Created on 2005-7-15*/ q%3<Juq~$
package com.adt.service; GRYe<