Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 p]Q(Z
BYZllwxwTE
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 'e*:eBoyb
3A'9=h,lVK
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 fiQ/ &]|5
F-<c.0;6
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 vpP8'f.
:auq#$B
。 X<uH [
NC%)SG \
分页支持类: OyATb{`'
yJ2A!id
java代码: rW[7
_4
)AXa.y
2$O6%0
package com.javaeye.common.util; :9W)CwZ)V
W:1GY#Pe
import java.util.List; jF6[+bW<
66'AaA;0^i
publicclass PaginationSupport { IRbZ ;*3dO
7,ffY/
publicfinalstaticint PAGESIZE = 30; *]e9/f
(P 9$Ei0fv
privateint pageSize = PAGESIZE; TB#oauJm,
p;rT#R&6>
privateList items; EoOwu-{
;|.IUXEgcF
privateint totalCount; V&>mD"~MP
, R $ZZ4
privateint[] indexes = newint[0]; 7Yly^
/S`d?AV
privateint startIndex = 0; e[%g'}D:-
ktiC*|fd
public PaginationSupport(List items, int K~
VUD(
_j?/O)M
c
totalCount){ }>?"bcJ
setPageSize(PAGESIZE); k2DBm q;
setTotalCount(totalCount); |\/V1
setItems(items); !z_VwZ#,
setStartIndex(0); PHqIfH [
} ^:]~6p#
3ms{gZbw
public PaginationSupport(List items, int AjMx \'(C
S*a_
totalCount, int startIndex){ $qk(yzY
setPageSize(PAGESIZE); CDGN}Q2 _
setTotalCount(totalCount); u
=|A
setItems(items); "kkZK=}Nv
setStartIndex(startIndex); qW t 9Tr
} BZRC0^-C@
r&D&xsbQ
public PaginationSupport(List items, int Gu\lV c
c{cJ>d 0
totalCount, int pageSize, int startIndex){ xyRZ
v]K1
setPageSize(pageSize); Z{
b($po
setTotalCount(totalCount); ?iaD;:'qE
setItems(items); S1W(]%0/
setStartIndex(startIndex); -{a&Zkz>V
} v`9n'+h-c6
<rFKJ^ B
publicList getItems(){ r?wE ;gH
return items; Pt8 U0)i)
} Xw<N nvz6
"~aCW~
publicvoid setItems(List items){ X5wYfN
this.items = items; Wj#Gm
} 5mF"nY&lI
IQQWp@w#8
publicint getPageSize(){ "P{T]
return pageSize; F<N{ x^
} I:,D:00+
Wo~#R
publicvoid setPageSize(int pageSize){ y1+~IjY
this.pageSize = pageSize; ee{8C~
} O;~dao
Pdw[#X<[`
publicint getTotalCount(){ 9Sk?tl
return totalCount; -<.b3M h
} mqb6 MnK -
e$y VV#
publicvoid setTotalCount(int totalCount){ ~$Pz`amT|
if(totalCount > 0){ FT.;}!"l
this.totalCount = totalCount; Oj^qh+r
int count = totalCount / J,]U"+;H
y}!}*Qj+/
pageSize; BjIKs~CT
if(totalCount % pageSize > 0) KsBi<wY
count++; -A17tC20J1
indexes = newint[count]; \t
04-
for(int i = 0; i < count; i++){ H}B%OFI \+
indexes = pageSize * [_?dp aTt
q/HwcX+[b
i; mo-
Y %
} iLD:}yK
}else{ &ZUV=q%g9n
this.totalCount = 0; &
!I$
} 5rx;?yvn
} sy;_%,}N
c;pv< lX'
publicint[] getIndexes(){ 6_h'0~3?`
return indexes; O6$d@r;EK]
} N M_Xy<.~E
9WhZ=
Xk
publicvoid setIndexes(int[] indexes){ ]7yr.4?a
this.indexes = indexes; }Pn]j7u!
} 27-GfC=7*
^E(:nxQ6s
publicint getStartIndex(){
dr iw\
return startIndex; P85@G
2
} BNe6q[ )W~
{*J{1)2
publicvoid setStartIndex(int startIndex){ X,"(G}KUA
if(totalCount <= 0) mIX[HDy:V$
this.startIndex = 0;
+*aZ9g
elseif(startIndex >= totalCount) *eonXJYD
this.startIndex = indexes Juqe%he`
~E tW B
[indexes.length - 1]; I>( \B| \6
elseif(startIndex < 0) vMB`TpZ
this.startIndex = 0; Wy`ve~y
else{ :AM5EO
this.startIndex = indexes
BHa'`lCb
-%eBip,'yl
[startIndex / pageSize]; z<c%Xl\$%
} .V Cfh+*J#
} ^yo~C3r~
>MeM
publicint getNextIndex(){ n6Qsug$z
int nextIndex = getStartIndex() + #[C=LGi
_rU%DL?
pageSize; 1SGLA"r
if(nextIndex >= totalCount) x<es1A'u6
return getStartIndex(); F+3}Gkn
else Lradyo44u\
return nextIndex; <yHa[c`L
} 3/i_?G
nF!6
publicint getPreviousIndex(){ bYKe5y=
int previousIndex = getStartIndex() - n$oHr
.!pr0/9B
pageSize; %!X|X,b^O
if(previousIndex < 0) ?' :v):J}
return0; awic9uMH
else P@wu k1
return previousIndex; %P2l@}?a
} =
olmBXn/
yxx'g+D*
} GF=rGn@,)`
B3V;
HDY2<Hzc
EDf"1b{PX
抽象业务类 0;V "64U
java代码: /
!@@
9$[PAjwk
NM{/rvM
/** =W_Pph
* Created on 2005-7-12 k:qS'
*/ G (o9*m1
package com.javaeye.common.business; /eO:1c
r$
8^K\oF
import java.io.Serializable; >{HQ"{Q
import java.util.List; PV\aQO.mo
8$TSQ~
import org.hibernate.Criteria; ;qN;oSK
import org.hibernate.HibernateException; cfP9b8JG
import org.hibernate.Session; QU;bDNq,c
import org.hibernate.criterion.DetachedCriteria; qG<3H!Z!ky
import org.hibernate.criterion.Projections; Lq6R_udp
import UqwU3
CVy\']
org.springframework.orm.hibernate3.HibernateCallback; nde_%d$
import W Y]
+\_c*'K>
org.springframework.orm.hibernate3.support.HibernateDaoS 6B=: P3Y
IGQcQ/M
upport; j*'+f~A
p"UdD
import com.javaeye.common.util.PaginationSupport; L<62-+e`
o<8('j
public abstract class AbstractManager extends e>] gCa
=+z +`ot
HibernateDaoSupport { NtfzAz/
aVvma=
privateboolean cacheQueries = false; w$##GM=Tq
A 6IrA/b
privateString queryCacheRegion; bQlv b
g]Jt (aYK
publicvoid setCacheQueries(boolean w5+H9R6
+ ;LO|!
cacheQueries){ lPyY
this.cacheQueries = cacheQueries; J_S8=`f%
} $&~moAl
2t,N9@u=UN
publicvoid setQueryCacheRegion(String qC x|}5:
Kt#_Ln_6
queryCacheRegion){ M(/ATOJ(
this.queryCacheRegion = W2Ik!wEe&
"\k|Z
queryCacheRegion; JuKG#F#,
} |W#(+m
6Lc{SR
publicvoid save(finalObject entity){ yt@7l]I
getHibernateTemplate().save(entity); cTJi8f=g
}
-k8<LR3
0Fw4}f.o
publicvoid persist(finalObject entity){ >'1[Bh
getHibernateTemplate().save(entity); }]
p9
} Fc6o6GyL|o
S 6CI+W
publicvoid update(finalObject entity){ -^aJ}[uaI
getHibernateTemplate().update(entity); [o"<DP6w
} ?:$\
t?e^
, UsY0YC
publicvoid delete(finalObject entity){ 2<FEn$n[
getHibernateTemplate().delete(entity); 2z9s$tp
} "P9(k>
PS}'LhZ
publicObject load(finalClass entity, KcvstC`
l+A)MJd oj
finalSerializable id){ ;l %$-/%
return getHibernateTemplate().load ?Gl]O3@3
"qrde4O
(entity, id); S"4eS,5L|
} @xXVJWEU:
nZ'-3
publicObject get(finalClass entity, ?XbM
`FGYc
finalSerializable id){ {sfA$ d0
return getHibernateTemplate().get vh#81}@N7*
4iI4+
(entity, id); :pfLa2f+
} ?Kt F!:_C
=(]Z%Q-V
publicList findAll(finalClass entity){ k-Yli21-/|
return getHibernateTemplate().find("from 'eo/"~/*w
;,}Dh/&E
" + entity.getName()); Z%Fc
-KVt
} 5%%e$o+
4`B3Kt`o
publicList findByNamedQuery(finalString _a#k3r
,v%'2[}
namedQuery){ 4_`(c1oA
return getHibernateTemplate 1Q/=s,{u
Kh$Q9$
().findByNamedQuery(namedQuery); E<l/o5<nC
} *4ido?
RH.qbPjx
publicList findByNamedQuery(finalString query, 5-hnk'
~
Z)}UCi+/".
finalObject parameter){ zM,r0Z
return getHibernateTemplate C-@[=
.VCF[AleS
().findByNamedQuery(query, parameter); D5bPF~q
} )bWopc
l*?_ @
publicList findByNamedQuery(finalString query, Z]e`bfNnI
+Bf?3 5LP
finalObject[] parameters){ s&hr$`V4
return getHibernateTemplate lA pZC6Iwk
P8(hHuO
().findByNamedQuery(query, parameters); ^Z-oO#)h#
} mqj-/DN6*
~Pj q3etk
publicList find(finalString query){ (3"N~\9m
return getHibernateTemplate().find %.m+6
zaF
ZTibF'\5N
(query); D4b-Y[/"
} VV{>Kq+&,v
aeISb83Y |
publicList find(finalString query, finalObject }T0O~c{$i
PY;tu#W!%
parameter){ <.mH-Y5i
return getHibernateTemplate().find AhD C5ue=
dU#-;/}o
(query, parameter); CLTkyS)C
} ;=7K*npT
V)5K/ U{
public PaginationSupport findPageByCriteria rlaeqG
W6Mq:?+ D
(final DetachedCriteria detachedCriteria){ '4nJ*Xa
return findPageByCriteria D#AqZS>B
Q~tXT_
(detachedCriteria, PaginationSupport.PAGESIZE, 0); m8=n `XI
} 0,nz*UDk
-V:HT
j
public PaginationSupport findPageByCriteria ,3!$mQL=
*E*oWb]H
(final DetachedCriteria detachedCriteria, finalint {zWR)o .=
9b/Dswxjx
startIndex){ ESNI$[`
return findPageByCriteria @ 5^nrB
a}uYv:
(detachedCriteria, PaginationSupport.PAGESIZE, hLbWqF
(Vr%4Z8
startIndex); %@Z;;5 L
} FpiTQC7d
b8e\( Dww
public PaginationSupport findPageByCriteria u4_QLf@I
3 3|t5Ia
(final DetachedCriteria detachedCriteria, finalint \nt~K}a
)q[P&f(h
pageSize, {9yf0n
finalint startIndex){ BY.k.]/
return(PaginationSupport) V
^+p:nP
J*[@M*R;&
getHibernateTemplate().execute(new HibernateCallback(){ 4Wp5[(bg
publicObject doInHibernate 'L7qf'RV
SIV !8mz
(Session session)throws HibernateException { h~m,0nGO
Criteria criteria = .07`nIs"
~N/r;omVc
detachedCriteria.getExecutableCriteria(session); mUbm3JIjJ
int totalCount = 4;I\%qes
|DV?5>>
((Integer) criteria.setProjection(Projections.rowCount ~W [I
mwo:+^v(
()).uniqueResult()).intValue(); !(rAI
criteria.setProjection QXZyiJX}
`XhH{*Q"X
(null); qx'0(q2Ii(
List items = c7jmzo
>;^/B R=
criteria.setFirstResult(startIndex).setMaxResults %\v8FCb
P{--R\
(pageSize).list(); H;
NV?CD
PaginationSupport ps = {2h*NFp
{_Wrs.a'8
new PaginationSupport(items, totalCount, pageSize, }! EVf
=nGFLH6)
startIndex); E=N$JM
return ps; uYMn VE"
} KGYbPty}
}, true); dMH_:jb
} UPI- j#yc
y)fMVD"(
public List findAllByCriteria(final +Yc^w5 !(
"esuLQC
DetachedCriteria detachedCriteria){ &em~+83
return(List) getHibernateTemplate -67Z!N
k1<^Ept
().execute(new HibernateCallback(){ $<v4c5r]O
publicObject doInHibernate KClkPL!jP
4<i#TCGex3
(Session session)throws HibernateException { NX&dJ
6a
Criteria criteria = >$JE!.p%o
i%-yR DIX
detachedCriteria.getExecutableCriteria(session); Hz.i $L0}
return criteria.list(); xoKK{&J
} )X0=z1$
}, true); ~.:{
Ik]
} G*I
lo$G*LWu:
public int getCountByCriteria(final R iLl\S#
+]eG=.
u
DetachedCriteria detachedCriteria){ = LNU%0m
Integer count = (Integer) a;xeHbE
mD'nF1o
Ly
getHibernateTemplate().execute(new HibernateCallback(){ W3,r@mi^s7
publicObject doInHibernate TcaW'&(K
)#m{"rk[x,
(Session session)throws HibernateException { F9
r5 Z
Criteria criteria = p<
7rF_?W0
G'\[dwD,u
detachedCriteria.getExecutableCriteria(session); ^3dc#5]Xf
return z}[u~P,
K=N&kda
criteria.setProjection(Projections.rowCount mD9Iao%4~
z\m$>C|
()).uniqueResult(); 7Mh'x:p
} a51(ySC}<s
}, true); AwZ@)0Wy
return count.intValue(); 1Vy8eI`4
} %unn{92)
} {N2GRF~c-y
H1k)ya x4_
|KhpF1/(
hoFgs9
jA1S|gV
SSI> +A
用户在web层构造查询条件detachedCriteria,和可选的 ]Ozz"4Z
8'Q+%{?1t
startIndex,调用业务bean的相应findByCriteria方法,返回一个 ] V/5<O1
}ekNZNcuM
PaginationSupport的实例ps。 f!+d*9
wo&IVy@s$
ps.getItems()得到已分页好的结果集 0aY|:
ps.getIndexes()得到分页索引的数组 %`bs<ZWT
ps.getTotalCount()得到总结果数 %g7j7$c
ps.getStartIndex()当前分页索引 I%4eX0QY=z
ps.getNextIndex()下一页索引 1O Ft}>1
ps.getPreviousIndex()上一页索引 e)HFI|>
{Vu=qNx
@{IX
do
f4S}Nga(
iX?j "=!
l3u [
D!* SA
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \ ERBb.
8;qOsV)UDT
,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 9uxoMjR-
AIP0PJI3
一下代码重构了。 ~e|E5[-i
tG]W!\C'h
我把原本我的做法也提供出来供大家讨论吧: iu=@h>C
#pWy%U
首先,为了实现分页查询,我封装了一个Page类: ~&,S xQT
java代码: <DqFfrpc
UaG&HGg]!
5aVZ"h"
/*Created on 2005-4-14*/ HZ(giAyjq
package org.flyware.util.page; di;~$rI!?
hB'rkjt
/** b 2\J<Nw
* @author Joa = m|<~t
* -4Q\FLC'k
*/ <&+0[9x
publicclass Page { v%#@.D!)
'QpDx&~QP
/** imply if the page has previous page */ "SuG6!k3
privateboolean hasPrePage; ,*[N_[
;Gp9
? 0
/** imply if the page has next page */ U8aNL
sw
privateboolean hasNextPage; IM,d6lN6s
=g%<xCp
/** the number of every page */ iOAn/[^xk
privateint everyPage; C,O9?t
ra
,.vJuT
/** the total page number */ ow+_g R-
privateint totalPage; ?J|
?nJv f
/** the number of current page */ k/Urz*O
privateint currentPage; 5HB*
U[pR`u
/** the begin index of the records by the current iYW<qgz
Bi/E{k,
query */ Lm^vS u
privateint beginIndex; Dz$dJF1
8
(nkiuCO
H ~<.2b
/** The default constructor */ H.Z<T{y;
public Page(){ ?wIw$p>wT
x9]vhR/av
} "?_af
Q{
g{
/** construct the page by everyPage eS%8WmCV9<
* @param everyPage ^%1u3
* */ #/t+h#jG
public Page(int everyPage){ {XXnMO4uR;
this.everyPage = everyPage; ;b|=osyT\
} n"I{aJ]K
j\@&poJ(,
/** The whole constructor */ 'O
7>w%#
public Page(boolean hasPrePage, boolean hasNextPage, ws;|fY
M>*xbBl
b-#oE{(\'
int everyPage, int totalPage, $}H,g}@0
int currentPage, int beginIndex){ nbv}Q-C
this.hasPrePage = hasPrePage; z
wn#E
this.hasNextPage = hasNextPage; ziQ&M\
this.everyPage = everyPage; Wq25, M'
this.totalPage = totalPage; ayg^js2,
this.currentPage = currentPage; V>4v6)N
this.beginIndex = beginIndex; 8y4t9V
} (F*y27_u
(s51GRC
/** :c:}_t{%
* @return
bIuOB|
* Returns the beginIndex. b-J6{=k^
*/ d(vt0
publicint getBeginIndex(){ ,W$&OD
return beginIndex; =+4om*
} k5X-*^U=V}
F\<{:wu
/** c&g*nDuDj
* @param beginIndex 0.~s>xXp
* The beginIndex to set. E,/nK
*/ QwnqysNx4
publicvoid setBeginIndex(int beginIndex){ S`h yRw
this.beginIndex = beginIndex; ] $F%
} uOx"oR|
BWkTQd<t
/** z|<?=c2P
* @return 5hDm[*83
* Returns the currentPage. bW GMgC
*/ Rf!$n7& \
publicint getCurrentPage(){ mW3IR3b
return currentPage; -c[fg+L9
} "i%=QON`
HC$}KoZkC
/** A4)TJY
3g
* @param currentPage 5_rx$avm
* The currentPage to set. $L72%T
*/ |4Os_*tRKU
publicvoid setCurrentPage(int currentPage){ ?0d#O_la3
this.currentPage = currentPage; $F@ ,,*
} ,/eAns`ZU
cZ,}1?!
/**
*n9=Q9
* @return e'3y^Vg
* Returns the everyPage. K{iC'^wP
*/ &3 x
[0DV
publicint getEveryPage(){ K*tomy
return everyPage; xE6hE'rh.O
} p%+'iDb
<@>l9_=R
/** }4q1"iMlO
* @param everyPage N3\vd_D(
* The everyPage to set. B*}:YV
*/ 2GRv%:rZ
publicvoid setEveryPage(int everyPage){ v+DXs!O{
this.everyPage = everyPage; NqN}] nu6
} gq.l=xS
CH0Nkf
/** j
HEt
* @return m :2A[H+
* Returns the hasNextPage. p|w0
i[hc
*/ oUL4l=dj.
publicboolean getHasNextPage(){ rotu#?B
return hasNextPage; "8\2w]"
} _rW75n=3b7
d M;v39
/** ]9}^}U1."
* @param hasNextPage wu0q.]
* The hasNextPage to set. rouaT
*/ $nNCBC=
publicvoid setHasNextPage(boolean hasNextPage){ O-n JuZJgX
this.hasNextPage = hasNextPage; !{b4+!@p
} G^le91$
G54`{V4&s
/** \$xj>b;
* @return AK&=/[U>
* Returns the hasPrePage. 6P02=
*/ PeJIa
%iE
publicboolean getHasPrePage(){ !WTL:dk
return hasPrePage; Fzy5k?R
} q!YAA\'31
Fm[3Btn
/** wT +\:y
* @param hasPrePage #l!nBY ~
* The hasPrePage to set. [6\b(kS+
*/ sL#MYW5E
publicvoid setHasPrePage(boolean hasPrePage){
,: qk+
this.hasPrePage = hasPrePage; ggy9euWV
} CsN^u H
cT
nC
/** V}Ce3wgvA
* @return Returns the totalPage. BR:Mcc
* eaDG7+iS
*/ D=}\]Krmay
publicint getTotalPage(){ sAoxLI
return totalPage; YVPLHwh/5
} 6K^O.VoV^J
wQ81wfr1:
/** No*[@D]g
* @param totalPage FzG>iC}
* The totalPage to set. %RzCJxT
*/ EKEJ9Y+47H
publicvoid setTotalPage(int totalPage){ 'i4L.&
this.totalPage = totalPage; M<P8u`)>4H
} :a9
tNz(s)
} P[tYu:
TrBW0Bn>p
U|x#'jGo'
[gj>ey8T
@]Lu"h#u=
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 LX#gc.c
gmZ] E45
个PageUtil,负责对Page对象进行构造: \85~~v@
java代码: 664D5f#EJ
/|isRh|
\J(kM,ZJ
/*Created on 2005-4-14*/ 9T0g%&
package org.flyware.util.page; `yO'-(@"gY
BO.Db``
import org.apache.commons.logging.Log; ^%!#Q].
import org.apache.commons.logging.LogFactory; y2=yh30L0E
G"h}6Za;DO
/** Nt/hF>"7
* @author Joa S q{@4F}d
* -_XTy!I
*/ z7TyS.z
publicclass PageUtil { n/S+0uT
~ 7<M6F
privatestaticfinal Log logger = LogFactory.getLog PlCj<b1D:
gyuBmY
(PageUtil.class); U*?`tdXJ$
Zn[ppsz|
/** qQ8+gZG$R
* Use the origin page to create a new page b7B|$T,
* @param page nlA:C>=
* @param totalRecords (p<pF].
* @return W||&Xb
*/ .eLd0{JtN
publicstatic Page createPage(Page page, int mv^X{T
: [7O=[pk
totalRecords){ l2I%$|)d
return createPage(page.getEveryPage(), SYa
O'c
%`YR+J/V
page.getCurrentPage(), totalRecords); [2E(3`-u
} h`iOs>
Hz)i.AA 4
/** l>KkAA
* the basic page utils not including exception lc3Gu78 A/
M=3gV?N
handler m=SI *V
* @param everyPage "lSh4X
* @param currentPage bc3`x1)\^
* @param totalRecords na"!"C
s3
* @return page T"<)B^8f
*/ 7Gy:T47T\@
publicstatic Page createPage(int everyPage, int o4wSt6gBcJ
jcb&h@T8kv
currentPage, int totalRecords){ |gIE$rt-~W
everyPage = getEveryPage(everyPage); fH$#vRcq
currentPage = getCurrentPage(currentPage); mhy='AQJ
int beginIndex = getBeginIndex(everyPage, 9zY6hh**
3R0ioi 7
currentPage); $sS~hy*
int totalPage = getTotalPage(everyPage, pdvnpzj
>F s/Wet
totalRecords); Qj*.Z4ue
boolean hasNextPage = hasNextPage(currentPage, xF@&wg
jFUpf.v2
totalPage); MpBdke$
boolean hasPrePage = hasPrePage(currentPage); FRQ0t!b<M1
ncMzHw
returnnew Page(hasPrePage, hasNextPage, &}
{ #g
everyPage, totalPage, um}q @BU
currentPage, &BRa5`
|Wjpnz
beginIndex); Pc2!OQC'""
} UtP|<]{
-Jw4z#/-
privatestaticint getEveryPage(int everyPage){ FSn3p}FVa
return everyPage == 0 ? 10 : everyPage; 6)7cw8^
} B(k tIy
@&Bh!_TWc
privatestaticint getCurrentPage(int currentPage){ E&eY79
return currentPage == 0 ? 1 : currentPage; ;j7G$s9
} K/K-u
I]E 3&gnC
privatestaticint getBeginIndex(int everyPage, int Qd{8.lB~LQ
qR_>41JU"
currentPage){ ^'a#FbMtt
return(currentPage - 1) * everyPage; bwH[rT!n
} 7ej u%d
>7zC-3
privatestaticint getTotalPage(int everyPage, int lo(C3o'
w jD<"p;P
totalRecords){ (zsv!U
int totalPage = 0; F"UI=7:o
6 dV )pJd
if(totalRecords % everyPage == 0) n\3#69VY
totalPage = totalRecords / everyPage; J=t}9.H~=
else N9-7YQ`D
totalPage = totalRecords / everyPage + 1 ; m|F1_Ggz
^6 z"@+;*
return totalPage; N2"B\
} bd~m'cob>
kS8?N`2}LV
privatestaticboolean hasPrePage(int currentPage){ 6(rN(C
return currentPage == 1 ? false : true; T7^;!;i`X
} `Z8k#z'bN
*=.~PR6W{
privatestaticboolean hasNextPage(int currentPage, }Sbk qd5
pCA`OP);=
int totalPage){ IEMa/[n/
return currentPage == totalPage || totalPage == -v.\W y~\
zh*D2/r
0 ? false : true; k$JOHru
} Uq$/Q7
.<F46?HS
U/^#nU.,
} 6]Is"3ca
^n(FO,8c
D2kmBZ3
nqm=snh
Z$JJ0X
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。 UZ2_FP
YLGE{bS
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 kuD$]A
Q`&
^2nrA pF
做法如下: {0Y6jk>I
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 BZ1wE1 t
/HpM17
的信息,和一个结果集List: +tT"
java代码: <D ~hhGb
T\uIXL?3
7I
XWv-
/*Created on 2005-6-13*/ e,/]]E/o
package com.adt.bo; ZK+F<}
jDpA>{O[
import java.util.List; }7[]d7
$Dj8 a\L
import org.flyware.util.page.Page; WSu6chz)
kpIn_Ea
/** Z%]K,9K
* @author Joa G?'^"ae"Z
*/ gVfFEF.
publicclass Result { uBx\xeI
$jg[6`L$
private Page page; _&hM6N
"u!gfG?oH
private List content; dX cbS<
<@KIDZYC
/** <&l$xn
* The default constructor =JIceLL
*/ gZ$
8Y7
public Result(){ Lz.khE<
super(); R+Hu?Dv&F
} |p&EP2?T
BZ?3=S1*
/** CF{b Yf^%
* The constructor using fields E5n7
<
* $qQYxx@
* @param page ]O"f %
* @param content M/=36{,w-
*/ ,r w4Lo
public Result(Page page, List content){ /B@{w-N
this.page = page; a31e.36g
this.content = content; k
i<X ^^
} 9f( X7kt
:}zyd;Rc
/** |NZi2Bu
* @return Returns the content. $:F+Nf
8
*/ OX]$Xdb2:
publicList getContent(){ _M%S
return content; ~4{q
} FpRYffT 9u
n?EgC8b9
/** KUUA>'=
* @return Returns the page. K>$f#^
*/ !Zj]0,^
public Page getPage(){ pY"WW0p"C
return page; &L+uu',M0c
} \Mg_Q$
1n8[fgz
/** e.n(NW
* @param content "=Br&FN{|
* The content to set. 1 P!)4W
*/
[P`e@$
public void setContent(List content){ ~V8z%s@
this.content = content; aZ4EcQ@-$]
} +)sX8zb*gY
lA5Dag'
/** n^4R]9U
* @param page 2Cz haO
* The page to set. ;|5-{+2 U%
*/ f,cd=vGj
publicvoid setPage(Page page){ P }sr
this.page = page; *H
Qc I-
} u1%URen[x
} ^9[Q;=R
.xsfq*3e5
Y~I<L ocv
`pfIgryns
*U[yeE].
2. 编写业务逻辑接口,并实现它(UserManager, @Dh2@2`>
FOXSs8"c]!
UserManagerImpl) LORcf 1X/
java代码: ,2S!$M
]c/E7|0Q
2FIL@f|\7z
/*Created on 2005-7-15*/ p\w<~pN[
package com.adt.service; 4nsJZo#S/
H$h#n~W~
import net.sf.hibernate.HibernateException; j<p.#jkT
I%3[aBz4
import org.flyware.util.page.Page; G\@pg;0|y
ljKIxSvCFp
import com.adt.bo.Result; +X=*>^G(-
Y,}_LS$f
/** Jl/w P
* @author Joa WoEK #,I;
*/ nq M7Is
publicinterface UserManager { p~$cwbQ!
O(T5
public Result listUser(Page page)throws FH~:&;
!T`oHs
HibernateException; dJ"M#X!Zu
'#'noB;,
} 4VJUu`[
3Z
b]@n
dvB=Zk]m
/|0-O''
6zi>Q?] 1
java代码: <CyU9`ye
]q]xU,
n=.P46|
/*Created on 2005-7-15*/ G !q[NRu
package com.adt.service.impl; G*CPj^O
o:Fq|?/e
import java.util.List; !zA@{gvEc
oW3"J6,S
import net.sf.hibernate.HibernateException; m@Z#
$h#sb4ek
import org.flyware.util.page.Page; o`bc/3!
import org.flyware.util.page.PageUtil; 2d&F<J<sU
9bM\ (s/
import com.adt.bo.Result; <Riz!(G
import com.adt.dao.UserDAO; 5C Dk5B_
import com.adt.exception.ObjectNotFoundException; [4z,hob
import com.adt.service.UserManager; p#@ #$u-
VfoWPyWD#
/** 3^sbbm.8
* @author Joa 5;a*Xf%V
*/ IO%kXF.[
publicclass UserManagerImpl implements UserManager { [l23b{
q(KjhM
private UserDAO userDAO; g>lZs
]S6Gz/4aV+
/** ?KC(WaGJQ
* @param userDAO The userDAO to set. x)PW4{3qR
*/ \9?[|m
z
publicvoid setUserDAO(UserDAO userDAO){ or]v]*:~l
this.userDAO = userDAO; 7UfNz60+~
} ZVjB$-do
WXQ@kQD
/* (non-Javadoc) X6Ha C+P
* @see com.adt.service.UserManager#listUser 02-ql
F@i
MEDh
(org.flyware.util.page.Page) /F0q8j0
*/ ^ ""edCs
public Result listUser(Page page)throws I|@+O#
/DQYlNa
HibernateException, ObjectNotFoundException { gEh/m.L7
int totalRecords = userDAO.getUserCount(); da$FY7
if(totalRecords == 0) zxyl+tU &
throw new ObjectNotFoundException :`bC3Mr
+jLy>=u
("userNotExist"); ^b8~X [1J_
page = PageUtil.createPage(page, totalRecords); H[=\_X1o(
List users = userDAO.getUserByPage(page); (80m'.X
returnnew Result(page, users); s0SzO,Vi
} 4#$#x=:
?
#K|l*
} ]E`<8hRB
Pe,>ny^J1
lTx_E#^s
^m>4<~/
^6s im 2
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 c!6D{(sfh
/5@YZ?|#2
询,接下来编写UserDAO的代码: 8w0~2-v.?V
3. UserDAO 和 UserDAOImpl: (@?mm
java代码: Rlq7.2cP
|L2>|4
SQodk:1)
/*Created on 2005-7-15*/ 384n1?
package com.adt.dao; DH(<{ #u
FQZ*i\G>>
import java.util.List; R<|\Z@z
].d2C J'
import org.flyware.util.page.Page; @^,q/%;
>ahDc!Jyu
import net.sf.hibernate.HibernateException; Y
;Ym=n'
Xaq;d'
/** hkMeUxS
* @author Joa 8!_jZ f8
*/ gQnr.
publicinterface UserDAO extends BaseDAO { 3jx%]S^z|
t~Q9}+
publicList getUserByName(String name)throws r.C6`
a
Z\!,f.>g
HibernateException; D!j/a!MaKk
xl}rdnf}
publicint getUserCount()throws HibernateException; S=@+qcI
}k^uup*{
publicList getUserByPage(Page page)throws p Cz6[*kC
]J7qsMw
HibernateException; J%&LQ