Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ka655O/)&
JpN+'/
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4~DoqT
N|wI=To
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 %kUIIHV}
|?g k%g
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 dG\dGSZ\h
D >$9(
。 G 7b>r
J'W6NitMr
分页支持类: }<m9w\pA
XI@;;>D1=U
java代码: ,iV|^]X3$/
*Mk5*_
u.43b8!
package com.javaeye.common.util; Y<odXFIS
<7-3j{065
import java.util.List; ;.+sz(:hm
f!AcBfaLr
publicclass PaginationSupport { bkTk:-L5:
#!qa#.Yi
publicfinalstaticint PAGESIZE = 30; Tc$Jvy-G4A
@p~f*b4H?
privateint pageSize = PAGESIZE; R1)v;^B|)
:+06M@
privateList items; [f 4Nq \i
`ZhDoLpH<
privateint totalCount; 7b7@"Zw*
8Th{(J_
privateint[] indexes = newint[0]; ,t2M ur
yy8h8{=g
privateint startIndex = 0; ei%L[>N
Pv@Lx+k
public PaginationSupport(List items, int j#6@cO'`
2[zFKK
totalCount){ 5FKb7
setPageSize(PAGESIZE); Z#+lwZD
setTotalCount(totalCount); m`_s_#
setItems(items); cgY+xd@
setStartIndex(0); -*HR0:H
} F/}(FG<'>I
WTK )SKa,.
public PaginationSupport(List items, int W!6&T [j>
&V"9[0
totalCount, int startIndex){ v"-@'qN'
setPageSize(PAGESIZE); d|I?%LX0p
setTotalCount(totalCount); kzozjh%`9h
setItems(items); "h58I)O
setStartIndex(startIndex); 2Tt^^Lb
} 2z#gn9Wb
?9W2wqN>o
public PaginationSupport(List items, int GE?M. '!{{
6)5Akyz4V
totalCount, int pageSize, int startIndex){ A}"aH
setPageSize(pageSize); |%\>+/j$
setTotalCount(totalCount); A43 mX!g\
setItems(items); q}x+#[Ef
setStartIndex(startIndex); n06T6oc
} 'Sk-L
5
Ct@O S227x
publicList getItems(){ Lgr(j60s
return items; ;fiH=_{us
} 9IfeaoZZ4q
so=Ux2
publicvoid setItems(List items){ KcPI,.4{
this.items = items; ny++U;qi
} NRIp@PIF:"
85gdmla@9
publicint getPageSize(){ ';,Rq9-'
return pageSize; ,;%F\<b
} uz
U2)n3y
jc0Trs{Jf
publicvoid setPageSize(int pageSize){ cI#! Y
this.pageSize = pageSize; I)s~kA.e
} KdN+$fe*g
v2K6y|6,
publicint getTotalCount(){ 5-[bd I
return totalCount; D^dos`L0b
} fC|NK+Xd`
m0M;f+^
publicvoid setTotalCount(int totalCount){ ;;f&aujSHD
if(totalCount > 0){ 9lU"m_
QT4
this.totalCount = totalCount; &GKtD)
int count = totalCount / A*x3O%zH
`bAOhaB,/
pageSize; 25R6>CXsi
if(totalCount % pageSize > 0) #]SiS2lM#
count++; x b6X8:
indexes = newint[count]; p Xap<T
for(int i = 0; i < count; i++){ M?[~_0_J
indexes = pageSize * FV~ENpncP
x%]5Q/|Ur
i; vHmsS\\~9
} nGoQwKIW
}else{ K3*8-Be
this.totalCount = 0; )y#~eYn
} ;:Kd?Tz$
} A,fP l R
hAi`2GP.
publicint[] getIndexes(){ CO5>Q o
return indexes; K+P:g%M
} %Eq4>o?D
myq:~^L
;
publicvoid setIndexes(int[] indexes){ _]aA58,j
this.indexes = indexes; AhA4IOG`.
} hH.X_X?d%
D #Ku5~j
publicint getStartIndex(){ p 3`odmbN
return startIndex; wbImE;-Z
} $v \@mW*R
D}i_#-^MH
publicvoid setStartIndex(int startIndex){ P;' xa^Y
if(totalCount <= 0) rfH'&k
this.startIndex = 0; .e Jt]K
elseif(startIndex >= totalCount) f=,(0ygt/
this.startIndex = indexes f%gdFtJ &
/\-iV)h1@
[indexes.length - 1]; ]
-}Zd\Rs
elseif(startIndex < 0) W|,Y*l
this.startIndex = 0; I
7 B$X=
else{ XLq%nVBM8\
this.startIndex = indexes Ec4+wRWk85
P/?'ea
[startIndex / pageSize]; c|hT\1XR,
} ) 1PjI9M
} m ,|)$R
0x1#^dII
publicint getNextIndex(){ jt6q8
int nextIndex = getStartIndex() + KEfx2{k b
Ex`!C]sQ
pageSize; 3v?R"2\qS
if(nextIndex >= totalCount) aePLP
return getStartIndex(); Oye:V
else TQ`4dVaf
return nextIndex; `=QRC.b
} &)Z!A*w]
K3I|d;Y~X!
publicint getPreviousIndex(){ A8jj]J+
int previousIndex = getStartIndex() - }<7S%?TY
GYJ
lX
pageSize; &ZR} Z7E*=
if(previousIndex < 0) V'Z Z4og
return0; V;-$k@$b.
else 9\J6G8b>|I
return previousIndex; @o/126(k
} L0QF(:F5
[+8in\T i
} r!C#PiT}I
YYs/r
W3~xjS"h
xp68-&
抽象业务类 d) i64"
java代码: }bA@QEJ
%j4AX
?nc:B]=pTY
/** , b;WCWm
* Created on 2005-7-12 GUH-$rA
*/ lXnzomU
package com.javaeye.common.business; N)0V6q"
-qW[.B
import java.io.Serializable; UZD Xv=r|
import java.util.List; ]8~{C>ch$
YZ.?
k4>
import org.hibernate.Criteria; -#agWqUM|T
import org.hibernate.HibernateException; ]ML(=7z"
import org.hibernate.Session; l.3|0lopX)
import org.hibernate.criterion.DetachedCriteria; IMT]!j&Y,
import org.hibernate.criterion.Projections;
|08'd5
import e]Q bC"
W[4 V#&Z
org.springframework.orm.hibernate3.HibernateCallback; ='z4bU
import Yb?L:,a(I
zho$g9*
org.springframework.orm.hibernate3.support.HibernateDaoS Op>l~{{{
+>*! 3x+sE
upport; J&w'0
1Vi3/JM@
import com.javaeye.common.util.PaginationSupport; D\CjR6DE
u+_6V
public abstract class AbstractManager extends "'@>cJ=
+B#+'
HibernateDaoSupport { *^=zQ~
\YMe&[C:o
privateboolean cacheQueries = false; _GF{Duxh
i[V\RKH*F
privateString queryCacheRegion; P+2@,?9#
wRsh@I<
publicvoid setCacheQueries(boolean ra]lC7<H
15dbM/Gj
cacheQueries){ 2b89th
this.cacheQueries = cacheQueries; E Z+L'
} -:~"c@D
>Y8\I
publicvoid setQueryCacheRegion(String ]mZN18#
\&#IK9x{
queryCacheRegion){ X Z4q{^o
this.queryCacheRegion = 7^<{aE:
Nay&cOz
queryCacheRegion; S:YQVj
} dHO8 bYBH
.sBwJZ
publicvoid save(finalObject entity){ vp2s)W8W
getHibernateTemplate().save(entity); , SB5"
} 5u=$m^@{
/_{B_2i/>
publicvoid persist(finalObject entity){ yNDplm|9*
getHibernateTemplate().save(entity); [#mRlL0yk
} ;'i>^zX`
<yg!D21Y
publicvoid update(finalObject entity){ B$D7}=|kc
getHibernateTemplate().update(entity); 8lZB3p]X
} @F/yc
mK_2VZj&
publicvoid delete(finalObject entity){ :ND e<6?u
getHibernateTemplate().delete(entity); dK d"2+fH
} kPvR ,
8H@] v@Z2
publicObject load(finalClass entity, W"[Q=$2<<
I:=rwnd
finalSerializable id){ 5!jU i9
return getHibernateTemplate().load 3Q:Hzq G
O;8 3A
(entity, id); hRaX!QcG3
} D\0qlCAs
zbgH}6b
publicObject get(finalClass entity, ({!S!k
1G`zwfmh~
finalSerializable id){ }[mLtv%&
return getHibernateTemplate().get b2Oj 1dP1
Zp qb0ro
(entity, id); HF;$Wf+=J
} MfG8=H2#|
PW QRy
publicList findAll(finalClass entity){ MiN|u
return getHibernateTemplate().find("from C.N#y`g
3;Y9<
" + entity.getName()); @|6#]&v`
} $az9Fmta
>hv8zHOO:
publicList findByNamedQuery(finalString vlVHoF;&
.8]buM5_G
namedQuery){ WWgJ !Uz
return getHibernateTemplate 7w5C
NV
Qy7 pM8~h
().findByNamedQuery(namedQuery); opfg %*
} v7b+
}F4%5go
publicList findByNamedQuery(finalString query, ;|r<mT/,
=HHtLW.|,
finalObject parameter){ JsK_q9]$e
return getHibernateTemplate BK)3b6L=%
Dj9ecV`
().findByNamedQuery(query, parameter); EV[ BB;eb
} %v)+]Ds{
{&uN q^Ch
publicList findByNamedQuery(finalString query, ap wA
+N2R'Phv
finalObject[] parameters){ g+%Pg@[
return getHibernateTemplate ,Fzuo:{uy
L2>
)HG
().findByNamedQuery(query, parameters); ]=G dAW
} r,Tq";N'
}DFZ9,gQ
publicList find(finalString query){ ( q}{;
return getHibernateTemplate().find ,buo&DT{L
;U[W $w[
(query); 7-("ppYX=
} @d_9NOmNT
;MH_pE/m
publicList find(finalString query, finalObject ZLlAK ?N
@pN6uDD}R
parameter){ yW@YW_2;4
return getHibernateTemplate().find @S)p{T5G
#3}!Q0
(query, parameter); yi:1cLq2
} 1k!$#1d<
=;{8)m
public PaginationSupport findPageByCriteria D!rD-e
"Tnmn@
(final DetachedCriteria detachedCriteria){ rYO~/N
return findPageByCriteria 'k9Qd:a}
Z)!#+m83>-
(detachedCriteria, PaginationSupport.PAGESIZE, 0); %TYe]^/'y
} 1
EwCF
'#u=wyp
public PaginationSupport findPageByCriteria Z> <,t~o}
S.|%dz
(final DetachedCriteria detachedCriteria, finalint }WnoI2
chXTFLC~
startIndex){ UHS{X~CS
e
return findPageByCriteria aC#{@t
o+g\\5s
(detachedCriteria, PaginationSupport.PAGESIZE, iJb-F*_y
>2ny/AK|
startIndex); O2S{*D={
} (".WJXB\
qdxDR
2]U
public PaginationSupport findPageByCriteria L8?;A9pc()
plgiQr #
(final DetachedCriteria detachedCriteria, finalint 7VW/v4n
IPk"{T3
pageSize, \4Z"s[8}
finalint startIndex){ 'tY y_
return(PaginationSupport) C^ZDUj`
&uXu$)IZ
getHibernateTemplate().execute(new HibernateCallback(){ N4w&g-
publicObject doInHibernate Dpkc9~z
g-<[* nF
(Session session)throws HibernateException { 5@EX,$h
Criteria criteria = wpa^]l
<4Ik]Uz^
detachedCriteria.getExecutableCriteria(session);
u"-."_
int totalCount = ,B$e'KQ
1i}p?sU
((Integer) criteria.setProjection(Projections.rowCount pykRi#[UrX
nmoC(| r
()).uniqueResult()).intValue(); t'* 2)U
criteria.setProjection /_i]bM7W
$!K,5^+
(null); k(dNHT
List items = $j&2bO5M
O4T_p=Xc
criteria.setFirstResult(startIndex).setMaxResults N:UA+
^3ysY24 Q
(pageSize).list(); Kgb<uXk
PaginationSupport ps = C8$/z>tQ
Q+Ya\1$6A
new PaginationSupport(items, totalCount, pageSize, /JmWiBQIn
0RP{_1k
startIndex); {}tv(8]^
return ps; m_b_)/
} [t"#4[
}, true); )w0K2&)A
} hSXZu?/
UB7C,:"
public List findAllByCriteria(final Xagz(tm/
VV"1I R
DetachedCriteria detachedCriteria){ \=
Wrh3
return(List) getHibernateTemplate w
C-x'
T^H`$;\
().execute(new HibernateCallback(){ 7vEZb.~4z
publicObject doInHibernate .`+N+B(4
yT h60U
(Session session)throws HibernateException { j]
Criteria criteria = U}SN#[*
&W?
hCr
detachedCriteria.getExecutableCriteria(session); %J:2y
return criteria.list(); \"l/D?+Q
} 2$1D+(5;
}, true); 0]2@T=*kTY
} *7K)J8kq
1VB{dgr
public int getCountByCriteria(final aKw7m={
_}Ec[c
DetachedCriteria detachedCriteria){ qQe23,x@5
Integer count = (Integer) @^^,VgW[
tV9 K5ON
getHibernateTemplate().execute(new HibernateCallback(){ ya'OI P `
publicObject doInHibernate no8FSqLUS~
kXW$[R
(Session session)throws HibernateException { W)2ZeH*
Criteria criteria = T4x[
\v5d
;{ESo?$*
detachedCriteria.getExecutableCriteria(session); -](3iPy}
return WxS$yUu
N>',[4pJ|
criteria.setProjection(Projections.rowCount 6adXE
rM)-$dZ
()).uniqueResult(); ?#VkzT
} Fr]B]Hj
}, true); b_-?ZmV^r
return count.intValue(); p"o_0{8
} #i|AE`
} 8&++S> <
we2D!Ywr
9pq-"?vHY0
HsAKz]Mq
E(0 [/N~
j/w*2+&v
用户在web层构造查询条件detachedCriteria,和可选的 lU% L
<amdPo+2D
startIndex,调用业务bean的相应findByCriteria方法,返回一个 t"FB}%G
6F08$,%Y
PaginationSupport的实例ps。
bj U]]
j(];b+>
ps.getItems()得到已分页好的结果集
BYXMbx
ps.getIndexes()得到分页索引的数组 +{@hD+
ps.getTotalCount()得到总结果数 o|c%uw
ps.getStartIndex()当前分页索引 Nx<%'-9)|
ps.getNextIndex()下一页索引 z#t;n
ps.getPreviousIndex()上一页索引 IGcYPL\&
Un{ 9reX5
@M8vPH
[h~#5x
"yc@_+"\+
qb>mUS
V.~C.x
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 j$}W%ibj
dnstm@0k
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ~ A4_
H@BU/{
一下代码重构了。 +BkmI\
afj[HJbY
我把原本我的做法也提供出来供大家讨论吧: t^(wbC
^.(i!BG'
首先,为了实现分页查询,我封装了一个Page类: ^y3snuLtE
java代码: +4m~D`fqt[
uz[5h0c
mNnt9F3Eq
/*Created on 2005-4-14*/ d9yfSZ
package org.flyware.util.page; f>jAu;S
7Un5Y[FZo
/** _J-3{a
* @author Joa `T~~yM)q
* rd!4u14
*/ g;t>jgX
publicclass Page { G|.5.FK^
Yp8GW1@
/** imply if the page has previous page */ z.]
privateboolean hasPrePage; V]0~BV
2^T`> ?{X
/** imply if the page has next page */ \EOPlyf8x
privateboolean hasNextPage; U+'h~P'4
e$=0.GWT
/** the number of every page */ t+m
ug
privateint everyPage; ylBjuD+
zIh`Vw ,t0
/** the total page number */ J#jx)K!
privateint totalPage; 6xAR:
B3-;]6
/** the number of current page */ DXc3u^
L
privateint currentPage; dMjAG7U
#ybtjsu'"U
/** the begin index of the records by the current I.RmBUq):s
WR@TH
bU
query */ w}
1~
privateint beginIndex; gDBdaxR<
9M!J7 W
Qlgii_?#@
/** The default constructor */ T{Y;-m
public Page(){ @>SirYh
o@blvW<v7
} CJ#1j>
^E`SR6_cmj
/** construct the page by everyPage |XoW
Z,K
* @param everyPage mQy!*0y
* */ Y> f 6
public Page(int everyPage){ C6cEt5
this.everyPage = everyPage; BaUcmF2Q
} S6bW?8`
i\z ,)xp
/** The whole constructor */ .iXIoka
public Page(boolean hasPrePage, boolean hasNextPage, jj8h>"d
@O Rk
euc|G Xs
int everyPage, int totalPage, *mTx0sQz(J
int currentPage, int beginIndex){ 1Wy0#?L
this.hasPrePage = hasPrePage; :{ Q[kYj
this.hasNextPage = hasNextPage; ";$rcg"%X
this.everyPage = everyPage; qZ|>{^a*
this.totalPage = totalPage; MW$
X4<*KD
this.currentPage = currentPage; pQf5s7
this.beginIndex = beginIndex; *='J>z.]
} j65qIw_Z
j`pX2S
/** -OPJB:7Z
* @return )S2GPn7
* Returns the beginIndex. B+8B<xZ
*/ SWrP0Qjc
publicint getBeginIndex(){ j`A 3N7;
return beginIndex; -"Hy%wE
} ~v+A6N:qC
HbXYinG%
/** p&|:,|jo5
* @param beginIndex ytg' {)
* The beginIndex to set. c mI&R(
*/ uF89B-t
publicvoid setBeginIndex(int beginIndex){ 236,o
{9e
this.beginIndex = beginIndex; 8%W(",nd
} 1 /dy@'
ir/-zp_
/** 27q=~R}
* @return "Gh5
^$w?j
* Returns the currentPage. aS,M=uqqK
*/ >GV= %
publicint getCurrentPage(){ yE4X6
return currentPage; eW>Y*l%B
} a8wQ,
m^M sp:T,
/** +#a_Y
* @param currentPage \Q m1+tg
* The currentPage to set. />,KWHR|:
*/ RC>79e/u<
publicvoid setCurrentPage(int currentPage){ qZz?i
this.currentPage = currentPage; !9ytZR*
} ub,GF?9
)ir*\<6Y=
/** WQ>y;fi5/{
* @return U3UDA
* Returns the everyPage. \2Atm,#4
*/ mOQN$d [
publicint getEveryPage(){ e[)oT
return everyPage; yRF
%SWO
} {InD/l'v6n
?@uyqi~:U
/** U&}v1wdZ3
* @param everyPage ^;@Q3~DpP%
* The everyPage to set. Y)oF;ko:
*/ ^vA"3Ixb!
publicvoid setEveryPage(int everyPage){ $>csm
this.everyPage = everyPage; }>
pNf
} lujUEHzp
7j22KQ|EX^
/** |k ]{WCD]
* @return S(\<@S&
* Returns the hasNextPage. w#Di
*/ `BOG e;pl
publicboolean getHasNextPage(){ z&a>cjt_;
return hasNextPage; n#Y=y#
} %{*A@jQsg
-m"9v%>Y
/** 2:4:Q[{A
* @param hasNextPage JsZLBq*lP
* The hasNextPage to set. 9\J.AAk~/
*/ <<5x"W(,
publicvoid setHasNextPage(boolean hasNextPage){ LI`H,2Km
this.hasNextPage = hasNextPage; [')C]YQb=
} ,N`cH\
e*?@6E
/** )GC9%mF;
* @return _a`J>~$
* Returns the hasPrePage. _d`)N
*/ &u}]3E'-k
publicboolean getHasPrePage(){ :*6#(MX
return hasPrePage; ,u&K(Z%
} |Y")$pjz
"gCqb;^
/** CL)*cu6zG
* @param hasPrePage N" =$S|Gs
* The hasPrePage to set. XJI
ff$K
*/ h:3^FV
publicvoid setHasPrePage(boolean hasPrePage){ :)eU)r"s4
this.hasPrePage = hasPrePage; B65"jy
} k`u.:C&
ObyF~j}j
/** ["65\GI?
* @return Returns the totalPage. DbIn3/WNe
* ' ] $mt
*/ 5dXDL~/2p
publicint getTotalPage(){ j
:$Ruy
return totalPage; 4!k0
} li7"{+ct
L7rH=gZ&!]
/** l =Is-N`
* @param totalPage ZtofDp5B
* The totalPage to set. D%%@+3a
*/ D]StDOmM
publicvoid setTotalPage(int totalPage){ "t!_bma
this.totalPage = totalPage; "eb+O
} !bGMVw6_
__OH
gp 1
} *< ?~
y|Vwy4tK9
PC55A1(T
=`W#R
=f\BAi
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 EWNm }C9
:|PI_
$4H
个PageUtil,负责对Page对象进行构造: .wvgHi
java代码: $z[r(a^a
kX8Ey
L+N;mI8
/*Created on 2005-4-14*/ 5`QN<4?%
package org.flyware.util.page; dc=~EG-_rM
>tQ$V<YB
import org.apache.commons.logging.Log; 57`*5X
import org.apache.commons.logging.LogFactory; YU6D;
9J4gDw4<
/** E~K5n2CI
* @author Joa f C_H0h3
* H5X.CcI&}
*/ r
t\eze_5A
publicclass PageUtil { "IuPg=|#
8d|#W
privatestaticfinal Log logger = LogFactory.getLog +txHj(Y`
U%u%_{-
(PageUtil.class); >V|KS(}s
y??^[ sB
/** ^"!)p2=
* Use the origin page to create a new page ;9"6g=q
* @param page Cj1nll8c
* @param totalRecords DR
c-L$bD
* @return 5ji#rIAhxh
*/ sMHP=2##
publicstatic Page createPage(Page page, int uz'MUT(68
r[W
Ir|r7
totalRecords){ 8Luw<Q
return createPage(page.getEveryPage(), ,WgEl4
qx2M"uFJ
page.getCurrentPage(), totalRecords); R
Y ";SfYb
} 8;GuJP\
MG(qQ#;j/
/** cj@ar^=`K
* the basic page utils not including exception /&!4oBna
"R
%3v.Z
handler o%_Hmd;_'
* @param everyPage *)xjMTJ%
* @param currentPage dQ`=CIr
* @param totalRecords O;H|nW}
* @return page m>&:)K}m
*/ * G0I2
publicstatic Page createPage(int everyPage, int $-p#4^dg
kpLx?zW--q
currentPage, int totalRecords){ TJ+,G4z
everyPage = getEveryPage(everyPage); kDWMget$
currentPage = getCurrentPage(currentPage); V PaW-o
int beginIndex = getBeginIndex(everyPage, rPXy(d1<`S
;JV(!8[
currentPage); 3\E G
int totalPage = getTotalPage(everyPage, '8V>:dy>
-W'T3_
totalRecords); cZl/8?dj}
boolean hasNextPage = hasNextPage(currentPage, linvK.Lf
}
3JOC!;;
totalPage); bW?cb5C
boolean hasPrePage = hasPrePage(currentPage); &E0L 2gbI
Q1^kU0M }
returnnew Page(hasPrePage, hasNextPage, v)s;
wD
everyPage, totalPage, Gz kvj:(V
currentPage, cTu"Tu\Qw
45U!\mG
beginIndex); 2e|m3
} Q~zs]{\
t*(buAx
privatestaticint getEveryPage(int everyPage){ ck\TTNA
return everyPage == 0 ? 10 : everyPage; \SyG#.$
} .Hm1ispq
(K`@OwD
privatestaticint getCurrentPage(int currentPage){ K(75)/
return currentPage == 0 ? 1 : currentPage; |$G|M=*LN
} =l+~}/7'Z
eiJ~1HX)
privatestaticint getBeginIndex(int everyPage, int {jOV8SVL
GFfZ TA
currentPage){ 3fd?xhWbN
return(currentPage - 1) * everyPage; 7;3;8Q FX
} $9rQ w1#e
D]NJ^.X
privatestaticint getTotalPage(int everyPage, int k4+ Q$3"
Ux+UcBKm-
totalRecords){ 9`T2
int totalPage = 0; qLa6c2o,
yP0XA=,Y
if(totalRecords % everyPage == 0) v]c+|nRs
totalPage = totalRecords / everyPage; I08W I u
else u`Abko<D
totalPage = totalRecords / everyPage + 1 ; ':#DROe!
:)DvZx HE@
return totalPage; Z Is=%6""&
} Apbgm[m|{
RhD
privatestaticboolean hasPrePage(int currentPage){ z#Db~
return currentPage == 1 ? false : true; |"i"8~/@<
} 0@/C5 v
rq![a};~
privatestaticboolean hasNextPage(int currentPage, mIah[~G
cxpG6c
int totalPage){ -s&7zqW
return currentPage == totalPage || totalPage == ^k5# {?I
fx*Q,}t
0 ? false : true; O\q-Ai
} Tu&W7aoX5
ufvjW]
!eA6Ejf
} ?L+|b5RS
<m0m8p"G
dLtmG:II
M@<r8M]G
4;V;8a\A
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 NEW0dF&)
qx";G
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 7_CX6:
8T}Dn\f
做法如下: 0s.X
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 1BOv|xPjZ
EFzPt?l
的信息,和一个结果集List: 8)XAdAr
java代码:
, )PpE&
;uN&yj<}a
Zy=DY
/*Created on 2005-6-13*/ ]/{iIS_
package com.adt.bo; V@pUU~6R
nQ08(8
import java.util.List; N4$ K{
Ls/*&u
import org.flyware.util.page.Page; |u_fVQj
tOxTiaa=
/** 04#<qd&ob@
* @author Joa Tl L\&n.$
*/ j|%>NB ):
publicclass Result { 3,)[Q?nKD
*QA{xvT
private Page page; 9{CajtN
Ib2n Bg>j
private List content; ;"JgNad
'c#AGi9
/** L7nW_
* The default constructor BE)&.}l
*/ MN[D)RKh;
public Result(){ & {=}U
super(); [7h/ 2La#
} l`rO)7
.s\_H,
/** J6gn!
* The constructor using fields B_S))3
* ccwz:7r
* @param page g4&f2D5
* @param content FXh*!%"*
*/ SS!b`
public Result(Page page, List content){ <['ucp
this.page = page; d"OYq
this.content = content; 3hfv^H
} hq?F81
ZwMd 22
/** 3u/ GrsF
* @return Returns the content. N*SUA4bnuM
*/ @`XbM7D 5
publicList getContent(){ EAV6qW\r5]
return content;
+Ou<-EQV
} g1I8_!}~
~T!D:2G
/** @T] G5|\ok
* @return Returns the page. S2:G#%EAa
*/ bK k7w#y
public Page getPage(){ iz3Hoj
return page; C=(~[ Y
} ";TqYk=-
k,LaFe`W
/** 7ea%mg\
* @param content &(h@]F!
* The content to set. L~*nI d
*/ T@mYHKu
public void setContent(List content){ Mo]aB:a
this.content = content; >%A~ :
} wU-Cb<^
zICAV -&
/** DaqlL
* @param page oF_
'<\ly=
* The page to set. ;i!$rL
*/ Z_s]2y1
publicvoid setPage(Page page){ F%$lcQ04%
this.page = page; 0Ok[`r`
} 2]V8-
} X0 ]Se(
m@"p#pt(_
Kh{_BdN
(5kL6d2
~^>g<YR[
2. 编写业务逻辑接口,并实现它(UserManager, (dP9`Na]
|8fdhqy_
UserManagerImpl) 9Us'Q{CD
java代码: wlpcuz@
0s6eF+bs
/4$ c-k
/*Created on 2005-7-15*/ 1w#vy1m J
package com.adt.service; Y4N)yMSl"
ekd;sEO
import net.sf.hibernate.HibernateException; tG[v@-O
G%U!$\j:qd
import org.flyware.util.page.Page; k#G+<7c<
$]MOAj"LH
import com.adt.bo.Result; U04)XfO;]
!,{-q)'D
/** -BH T'zq1S
* @author Joa \~.elKw<U
*/ n<Ki.;-ZE
publicinterface UserManager { rB_ESNx
Mo\nY5
public Result listUser(Page page)throws ([]\7}+8
gB0Q0d3\G,
HibernateException; M7ug<
8i
[ZD`t,x(
} X/H2c"!t
)2J#pz?.
EUS^Gtc
1-Q>[Uz,
G{0f*
cH)
java代码: !J(6E:,b#
a>S-50
$YK~7!!
/*Created on 2005-7-15*/ ~>$z1o&}.
package com.adt.service.impl; ' wKTWmf?\
|sB L(9
import java.util.List; -v=tM6
|T{ZDJ+
import net.sf.hibernate.HibernateException; 5#::42oE
iOiXo6YE
import org.flyware.util.page.Page; Hnf?`j>
import org.flyware.util.page.PageUtil; Z|j\_VKhl
p7[&H