Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 <.DFa/G
"kLu]M<
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 .,)C^hs@
j^t#>tZS
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 9q?\F
_TB,2 R
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 1eg/<4]hA
dG6 G
。 H`js1b1n
F"3LG"
分页支持类: 4CzT<cp
=~)J:x\F
java代码:
G_fP%ovh
'T(7EL3$}
C^}2::Qu
package com.javaeye.common.util; 9WXJz;
@Axwj
import java.util.List; X*Ibk-PUM
7^{M:kYC!
publicclass PaginationSupport { ]h(}%fk_
P1<Y7+n
publicfinalstaticint PAGESIZE = 30; lJ+05\pE
HFJna2B`
privateint pageSize = PAGESIZE; QB<9Be@e
*W'F6Hpu
privateList items; mN>7vJ
y"|QY!fK
privateint totalCount; K$S:V=y%r7
Z9:erKT
privateint[] indexes = newint[0]; 7pB5o2CD0
j,q8n`@
privateint startIndex = 0; E0;KTcZi
c:
/Wk
public PaginationSupport(List items, int 6$1dd#
ZRDY`eK
totalCount){ ?o@5PL
setPageSize(PAGESIZE); 0]x g E
setTotalCount(totalCount); hXsd12
setItems(items); BPp`r_m8w}
setStartIndex(0); q Ee1OB
} gW{<:6}!*
a[<'%S#3x
public PaginationSupport(List items, int w"s;R8
U@W3x@
totalCount, int startIndex){ 8|>$M
setPageSize(PAGESIZE); %SKp<>;9
setTotalCount(totalCount); 9:|z^r
setItems(items); XcOfQs
setStartIndex(startIndex); "}_b,5lkGK
} 4)L(41h
9(;5!q,Gsg
public PaginationSupport(List items, int TO&ohATp
.A;e`cKb
totalCount, int pageSize, int startIndex){ hE|Z~5\Y,>
setPageSize(pageSize); c/l%:!A
setTotalCount(totalCount); r-M:YB
setItems(items); ZLsfF
=/G
setStartIndex(startIndex); /.Yf&2X\
} "N"$B~W*
ao4"=My*G
publicList getItems(){ P`/;3u/P
return items; "/ N ?$
} m3Mo2};?
;7id![KI4
publicvoid setItems(List items){ [E9V#J89
this.items = items; ,EkzBVgo
} H .F-mm
qJjXN+/D
publicint getPageSize(){ ws"{Y+L
return pageSize; NSQ}:m
} (IlHg^"
9g*O;0 uz
publicvoid setPageSize(int pageSize){ cT2&nZ
this.pageSize = pageSize; (mO{W
} ~d0:>8zQR
kEQ1&9
publicint getTotalCount(){ T:v.]0l~
return totalCount; bW"bkA80
} _n6ge*,E
kF%EJuu
publicvoid setTotalCount(int totalCount){ C5}c?=#bdf
if(totalCount > 0){ w %4SNR
this.totalCount = totalCount; 75@!j[QL<
int count = totalCount / |l4tR
bjn: e!}
pageSize; W<f-
if(totalCount % pageSize > 0) W''%{A/'
count++; icO$9c
indexes = newint[count];
fQW1&lFT
for(int i = 0; i < count; i++){ w=NM==cLj
indexes = pageSize * mS\gh)<h
j6!C/UgQ
i; o#"U8N%r
} i-.]onR
}else{ / //
this.totalCount = 0; :n#8/'%1
} \a#{Y/j3
} PK C}!>2
KT5amct
publicint[] getIndexes(){ M~rN17S
return indexes; ZmLA4<
} 6o5NeKZ
\d'>Ky;GD
publicvoid setIndexes(int[] indexes){ [Rj_p&'
this.indexes = indexes; !.2tv
} 7
KuUV!\h`
C VXz>oM
publicint getStartIndex(){ @AB}r1E2
return startIndex; F"-u8in`
} ?-Qq\D^+
n-"(lWcp
publicvoid setStartIndex(int startIndex){ W
u C2LM
if(totalCount <= 0) _p^?_
this.startIndex = 0; {PGiNY%q
elseif(startIndex >= totalCount) mNII-XG
this.startIndex = indexes pZ`^0#Fo
9QXBz=Fnf
[indexes.length - 1]; ut*sx9l
elseif(startIndex < 0) <)68ol~<
this.startIndex = 0; (]@yDb4
else{ qjm6\ii:)
this.startIndex = indexes (DIMt-wz
KgH_-REN
[startIndex / pageSize]; Jkx_5kk/\
} gmqL,H#
} i5*BZv>e
QmKEl|/{u
publicint getNextIndex(){ .),Fdrg
int nextIndex = getStartIndex() + LJgGX,Kp
(y^svXU}a
pageSize; qg06*$%
if(nextIndex >= totalCount) 0Yk$f1g
return getStartIndex(); NiSyb yR$
else tqFE>ojlI
return nextIndex; p
2>\
} j5:/Gl8
Z?f-_NHg
publicint getPreviousIndex(){ Q{o ]^tN
int previousIndex = getStartIndex() - $=9g,39
|e_'%d&
pageSize; 5M&<tj/[a0
if(previousIndex < 0) {9XN\v=$"*
return0; HkQ rij6
else pwg\b
return previousIndex; 9 gc0Ri[4m
} $xqX[ocor
D & Bdl5g
} u.@B-Pf[Eo
"oT&KW
zq'KX/o
P,s>xM
抽象业务类 AsfmH-4)
java代码: szs.B|3X@*
(:>Sh0.
3rj7]:Vr
/** veAdk9
* Created on 2005-7-12 8dLK5"_3
*/ _Wtwh0[r*
package com.javaeye.common.business; 1wy?<B.f
`sLD>@m
import java.io.Serializable; f;%=S:3
import java.util.List; Q%QIr
blKF78
import org.hibernate.Criteria; 2Ah B)8bG
import org.hibernate.HibernateException; HE:]zH
import org.hibernate.Session; a] P0PH~
import org.hibernate.criterion.DetachedCriteria; K*P:FCz
import org.hibernate.criterion.Projections; 6J<R;g23R]
import Oh3A?!y#
2-%9k)KH
org.springframework.orm.hibernate3.HibernateCallback; KjK-#F,@
import r-AD*h@QZ
629ogJo8
org.springframework.orm.hibernate3.support.HibernateDaoS &<EixDi4q
EvptGM
upport; |~B` [p]5H
moCR64n
import com.javaeye.common.util.PaginationSupport; =J`M}BBx
skF}_
public abstract class AbstractManager extends 1Q7]1fRu
/<k]mY cu
HibernateDaoSupport { M7=|N:/_
32p9(HQ
privateboolean cacheQueries = false; #s{EIj~YR_
<q`|,mc
privateString queryCacheRegion; dN@C)5pm5`
4t 0p!IxG
publicvoid setCacheQueries(boolean L=gG23U&
'yR\%#s6
cacheQueries){ 0lU
pil
this.cacheQueries = cacheQueries; W)AfXy
} <=!FB8 .
Q[9W{l+
publicvoid setQueryCacheRegion(String EUbyQL
zFr#j~L"
queryCacheRegion){ ,+v>(h>q
this.queryCacheRegion = /H$:Q|T}
gkDXt^Ob
queryCacheRegion; |<JBoE]3B
} WO*dO9O
kBtzJ#j B
publicvoid save(finalObject entity){ SP;1XXlL
getHibernateTemplate().save(entity); 1sq1{|NW~
} &kQj)
"(iQ-g Mm
publicvoid persist(finalObject entity){ '26
,.1
getHibernateTemplate().save(entity); /k KVIlO
} q!WiX|P
2LS91
publicvoid update(finalObject entity){ ~<"{u-q#K
getHibernateTemplate().update(entity); {a,U{YJ\H
} A3|X`X
%>1C($^
publicvoid delete(finalObject entity){ 2]E i4%jo
getHibernateTemplate().delete(entity); k/i&e~! \
} oGL2uQXX
Ah;`0Hz;
publicObject load(finalClass entity, :Aj[#4-=
(Ft#6oK"
finalSerializable id){ +*G<xW :M
return getHibernateTemplate().load lt%9Zgr[u
lr=quWDY
(entity, id); c1<jY~U
} |Ew&. fgz
26MoYO!k
publicObject get(finalClass entity, zANsv9R~
OG^#e+
finalSerializable id){ :/6u*HwZh
return getHibernateTemplate().get @Py?.H
VP^{-mDph
(entity, id); %F(lq*8X
} 7b(r'b@N
N~DO_^
publicList findAll(finalClass entity){ 5:T}C@
return getHibernateTemplate().find("from fz rH}^
HFX,EE
" + entity.getName()); ?+L7Bd(EF%
} ~I@ %ysR
gH0Rd
WX
publicList findByNamedQuery(finalString Dk}txw}#
mzcxq:uZ5
namedQuery){ CIQ9dx7>
return getHibernateTemplate \F<C$cys\
uCj)7>}v{M
().findByNamedQuery(namedQuery); _3{8Zg
} V5+|H1=
}BiA@n,
publicList findByNamedQuery(finalString query, [pz1f!Wn
rGzGbI=
finalObject parameter){ ki8Jl}dr
return getHibernateTemplate |al'_s}I
B]PG
().findByNamedQuery(query, parameter); I9YMxf>nI
} >viLvDng
z=TuUl@
publicList findByNamedQuery(finalString query, \n-.gG
R".*dC,0'B
finalObject[] parameters){ 3#idXc
return getHibernateTemplate .19_EQ>+
1t7T\~+F
().findByNamedQuery(query, parameters); ;MW=F9U*
} QS<)*
C`\yc_b9Pf
publicList find(finalString query){ (n2=.9k!
return getHibernateTemplate().find aK8X,1g%)
/Mw0<#
(query); _
Uv3glK
} *-s':('R
]gVW&3ZW
publicList find(finalString query, finalObject `'ak/%Krh
>"D0vj
parameter){ ;eP.B/N
return getHibernateTemplate().find xsg55`
|q 0iX2W
(query, parameter); `Wu.wx
} MwWN;_#EO)
3#h@,>Z;
public PaginationSupport findPageByCriteria Ar`U/ %Cu
<KZ J
(final DetachedCriteria detachedCriteria){ tS[@?qP
return findPageByCriteria e_llW(*l8^
bRx}ih
(detachedCriteria, PaginationSupport.PAGESIZE, 0); y9K'(/
} `W %R
nc:K!7:
public PaginationSupport findPageByCriteria }nWW`:t kx
3EyVoS6D
(final DetachedCriteria detachedCriteria, finalint K}Lu1:~
_%<qZT
startIndex){ NJ(H$tB@
return findPageByCriteria 6{2 9cX.
|]OI)w*
(detachedCriteria, PaginationSupport.PAGESIZE, <2fvEW/#v
SoB6F9
startIndex); Yu|L6#[E
} C oO0~q
^%/d]Zwb
public PaginationSupport findPageByCriteria 3$ BYfI3H
"XKd#ncP
(final DetachedCriteria detachedCriteria, finalint |$c~Jq
M;E$ ]Z9
pageSize, vFsl]|<;8
finalint startIndex){ %~qY\>
return(PaginationSupport) t<znz6
?^
`EI}g
getHibernateTemplate().execute(new HibernateCallback(){ ;V4f6[<]'z
publicObject doInHibernate 4"Pf0PD:
6g'+1%O
(Session session)throws HibernateException { ),f d,
Criteria criteria = f_ UwIP
\>
detachedCriteria.getExecutableCriteria(session); hi9@U]H#
int totalCount = N"2P]Zr
L_}F.nbS5
((Integer) criteria.setProjection(Projections.rowCount \rmge4`4
1)ZdkTF@H
()).uniqueResult()).intValue(); &y.6Hiy&
criteria.setProjection 1'9YY")#
IJofbuzw:
(null); yx/.4DW1Ua
List items = hB-<GGcO <
iPt{v5}]
criteria.setFirstResult(startIndex).setMaxResults `Qo}4nuRs
??=7pFm
(pageSize).list(); $|}PL[aA#
PaginationSupport ps = 6#1:2ZHKG
>y
iE}
new PaginationSupport(items, totalCount, pageSize, XnV$}T:?X
FY <77i
startIndex); B e2yS]U
return ps; "6o5x&H
} F[==vte|
}, true); Ixv/xI
} qn~:B7f
!<j)D_
public List findAllByCriteria(final Q)}z$h55
73kL>u
DetachedCriteria detachedCriteria){ kS$m$
D
return(List) getHibernateTemplate c9R|0Yn^J
]$?\,`
().execute(new HibernateCallback(){ =E'
.T0v
publicObject doInHibernate f2RIOL,
>X-*Hu'U#
(Session session)throws HibernateException { M]M(E) *5
Criteria criteria = t'L#8MJ
UvM_~qo
detachedCriteria.getExecutableCriteria(session); qn|~z@"
return criteria.list(); ${)s
~[
} g\foBK:GE
}, true); '7TT4~F
} ad[oor/7|
?tFsSU
public int getCountByCriteria(final lM-*{<B
YR}By;Bq
DetachedCriteria detachedCriteria){ R3Ka^l8R|
Integer count = (Integer) XbKNH>
D^e7%FX
getHibernateTemplate().execute(new HibernateCallback(){ YN 31Lo
publicObject doInHibernate DB;Nr3x
q X>\*@
(Session session)throws HibernateException { Q XV8][
Criteria criteria = f!aE/e\
%e'Z.vm
detachedCriteria.getExecutableCriteria(session); K5SP8<.
return Ig M_l=
o:"^@3
criteria.setProjection(Projections.rowCount m5rJY/
58H%#3Fy
()).uniqueResult(); .WT^L2l%
} VPqMbr"L[
}, true); BbdJR]N/!h
return count.intValue(); K]Onb{QY
} ;5wr5H3
} &b7i> ()
gaXKP1m^
Y94/tjt
WbP*kV{
"~HV!(dRMC
duk:: |{F
用户在web层构造查询条件detachedCriteria,和可选的 s.7s:Q`
a4L0Itrp
startIndex,调用业务bean的相应findByCriteria方法,返回一个 81<0B@E
1_z6O!rx
PaginationSupport的实例ps。 ^#A[cY2eM
`Ufv,_n
ps.getItems()得到已分页好的结果集 @ dF]X
ps.getIndexes()得到分页索引的数组 /P3s.-sL
ps.getTotalCount()得到总结果数 /K@{(=n
ps.getStartIndex()当前分页索引 p*
ps.getNextIndex()下一页索引 tuiQk=[c
ps.getPreviousIndex()上一页索引 XgmblNp1
s"solPw
,$qqHSd1M
MlM2(/ok
5h4E>LB.B
6b8@6;&LI
@~l?hf
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 FTg4i\Wp
j{;RuNt
,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 GqrOj++>
23;e/Qr
一下代码重构了。 WZ<kk T
X0.-q%5
我把原本我的做法也提供出来供大家讨论吧: EdPN=
E(&GZ QE
首先,为了实现分页查询,我封装了一个Page类: l^IPN'O@
java代码: C;jV{sb9c
>Lo!8Hen
VnJ-nfA
/*Created on 2005-4-14*/ D-8>?`n\
package org.flyware.util.page; -|DSfI#j
R "&(Ae?LR
/** yq?_#r
* @author Joa u%7a&1c
* <}E^r_NvD
*/ /I'n]
publicclass Page { Hhbf9)
Y"uFlHN&i
/** imply if the page has previous page */ ')9%eBaeK
privateboolean hasPrePage; %acy%Sy
sX&M+'h
/** imply if the page has next page */ !k&~|_$0@
privateboolean hasNextPage; mF>CH]k3
MGO.dRy_
/** the number of every page */ Or9@ X=C
privateint everyPage; T$]2U>=<J
2.2Z'$W
/** the total page number */ ?;,Al`/^
privateint totalPage; |<.b:e\4
v`hv5wQ
/** the number of current page */ eh'mSf^=p
privateint currentPage; 7[-jr;v
9xg_M=72
/** the begin index of the records by the current \QUvImT
f*~ 4Kv
query */ 34C
^vBp
privateint beginIndex; l\^q7cXG
%6<Pt
71tMX[x
/** The default constructor */ Et'C4od s
public Page(){ bIm$7a`T
$UjSP
} JMOP/]%D
&Jj> jCg
/** construct the page by everyPage 4Uf+t?U9
* @param everyPage +&\TdvNI4
* */ P&aH6*p1
public Page(int everyPage){ >V(2Ke Y
this.everyPage = everyPage; U8-9^}DBA
} 5?kA)!|UB
eq/5$b(
/** The whole constructor */ \| >eG u
public Page(boolean hasPrePage, boolean hasNextPage, VP 4t~$"
H>XbqIkL@
w=e,gNO
int everyPage, int totalPage, Xy*X4JJh^
int currentPage, int beginIndex){ |V9%@
Y?
this.hasPrePage = hasPrePage; 8
(^2
this.hasNextPage = hasNextPage; <(p1
j0_Q
this.everyPage = everyPage; \Di~DN1
this.totalPage = totalPage; ,f?#i%EF&
this.currentPage = currentPage; J+*rjdI
this.beginIndex = beginIndex; 3}:pD]`h
} J#V`W&\,6
nv $
/** Aq'%a)Y2
* @return j|G-9E
* Returns the beginIndex. deTbvl
*/ ex!^&7Q(
publicint getBeginIndex(){ $PS5xD~@
return beginIndex; x>8f#B\Mr
}
18A&[6"!
H9)uni
/** 2FVKgyV
* @param beginIndex 8e\v5K9
* The beginIndex to set. UdI>x 4bI
*/ :
m5u=:t
publicvoid setBeginIndex(int beginIndex){ rFy9K4D
this.beginIndex = beginIndex; Ba+OoS
} zRJy3/>
oM7^h3R
/** ONGe/CEXT
* @return ^p7(
* Returns the currentPage. qBNiuV;*
*/ ,xh9,EpBk
publicint getCurrentPage(){ yX~[yH+Pn
return currentPage; CXQ?P
} #wjBMR%
'j3'n0o
/** C95,!q
* @param currentPage o7T|w~F~R
* The currentPage to set. 7.Mh$?;i9
*/ Y>#c2@^i<
publicvoid setCurrentPage(int currentPage){ #]
GM#.
this.currentPage = currentPage; 5?fk;Q9+\
} UA8!?r-cR
ww,c)$
/** *"CvB{XF&Z
* @return {;}8Z $
* Returns the everyPage. >gSerDH8\
*/ /<
:;^B
publicint getEveryPage(){ jFXU
xf
return everyPage; VxFy[rP
} -0X> y
[]]3"n
/** 0&\Aw'21
* @param everyPage 'AAY!{>
* The everyPage to set. w?tKL0c
*/ E&+^H
on
publicvoid setEveryPage(int everyPage){ 84[^#ke
this.everyPage = everyPage; =e;wEf%`
} UH.cn|R
O%&@WrFq
/** ?W
n(ciO
* @return HIq1/)
* Returns the hasNextPage. EDo@J2A
*/ t4IJ%#22
publicboolean getHasNextPage(){ 4B]61|A
return hasNextPage; `g1Oon_
} {Pb^Lf >
9^ r
/** -"e}YN/
* @param hasNextPage RNdnlD#P
* The hasNextPage to set. 4iz&"~&1
*/ #FB>}:L{h*
publicvoid setHasNextPage(boolean hasNextPage){ m=MT`-:
this.hasNextPage = hasNextPage; B0i}Y-Z
} Y*k<NeDyn
yU|ji?)e
/** \vsrBM
* @return pCmJY
* Returns the hasPrePage. :6?&FzD`
*/ g8+,wSE
publicboolean getHasPrePage(){ ge?-^s4M
return hasPrePage; 3~</lAm;
} l~YNmmv _
M@g
gLW
/** udGGDH
* @param hasPrePage 5{q/z^]
* The hasPrePage to set.
_)E8XyzF
*/ ennz/'
publicvoid setHasPrePage(boolean hasPrePage){ t4@g;U?o
this.hasPrePage = hasPrePage; xD#I&.
} #U52\3G
!2|`aa
/** A9UaLSe
* @return Returns the totalPage. 8MeXVhM
* iFG5%>5F
*/ 3Z:!o$
publicint getTotalPage(){ :5M}Iz7
return totalPage; |/^aLj^u
} .eNwC .8i
Kw0V4UF
/** Z034wn\N
* @param totalPage K}`p_)(
* The totalPage to set. b*F~%K^i$
*/ Y"kS!!C>[
publicvoid setTotalPage(int totalPage){
Jf<yTAm
this.totalPage = totalPage; tc<M]4-
} yr9A0F0
^Pg
YP
} Zmbz-##HQ
qb>r\bc
BMWeD
E'S;4B5?
L+rySP
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 +'j*WVE%5
sQ:VrXwP
个PageUtil,负责对Page对象进行构造: JJ9e{~0I
java代码: i?_D]BY4
!BQ ELB$0
5'c+313 lm
/*Created on 2005-4-14*/ a^\- }4yR
package org.flyware.util.page; G'?f!fz;
Ky9No"o
import org.apache.commons.logging.Log; ZYR,8 y
import org.apache.commons.logging.LogFactory; [^d6cMEOlc
KT;C RO>
/** _l!U[{l*d
* @author Joa e|5B1rMM
* 76_8e{zbr
*/ v(@+6#&
publicclass PageUtil { .H(}[eG_
[+MH[1Vr={
privatestaticfinal Log logger = LogFactory.getLog t:"=]zUU
w
HHF=Q
(PageUtil.class); @t;O"q'|
;TV'PJ
/** W`/jz/
* Use the origin page to create a new page \B>[je-d
* @param page kL PO+lg+
* @param totalRecords \|pK Z6*s
* @return MY?O/,6
*/ !w#ru?L{
publicstatic Page createPage(Page page, int JM+sHHs
Qk~0a?#y5
totalRecords){ h*\TCl)
return createPage(page.getEveryPage(), WrHgF*[
$E`iqRB
page.getCurrentPage(), totalRecords); PD}SPOA`U3
} HzG~I8o(d
!|Xl 8lV`
/** ?`T6CRZhr
* the basic page utils not including exception r>Qyc
=Y]'5cn{
handler #zSi/r/=1
* @param everyPage K.#,O+-Kg`
* @param currentPage `hK>bHj
* @param totalRecords {?
K|(C
* @return page @ yg|OA}
*/ zqvRkMWc M
publicstatic Page createPage(int everyPage, int XMeL^|D
_
r^90
currentPage, int totalRecords){ A4#3O5kij
everyPage = getEveryPage(everyPage); 6cQeL$,SQ
currentPage = getCurrentPage(currentPage); iJdrY6qd
int beginIndex = getBeginIndex(everyPage, j:v~MrQ7|
BYr_Lz|T
currentPage); $K6?(x_
int totalPage = getTotalPage(everyPage, ,Ou1!`6?t
i3M?D}(Bs
totalRecords); ')P2O\YS
boolean hasNextPage = hasNextPage(currentPage, [U%ym{be^
1IOo?e=/bM
totalPage); F=
_uNq
boolean hasPrePage = hasPrePage(currentPage); as\<nPT{Fj
kO..~@aY
returnnew Page(hasPrePage, hasNextPage, nl)_`8=
everyPage, totalPage, ?dJ/)3I%F
currentPage, ~{1/* &P
e9z$+h
beginIndex); B&4fYpn
} )d770Xg+
iioct_7,g<
privatestaticint getEveryPage(int everyPage){ 097Fvt=#
return everyPage == 0 ? 10 : everyPage; 2A*X Hvwb
} vi[#?;pkF
GZ/pz+)i&
privatestaticint getCurrentPage(int currentPage){ mHK@(D7X
return currentPage == 0 ? 1 : currentPage; Aj8l%'h[
} w|!YoMk+o
tsTR2+GZS
privatestaticint getBeginIndex(int everyPage, int Z-^uM`],G
iX8h2l
currentPage){ G*P[z'K=
return(currentPage - 1) * everyPage; N`,7 FI}
} 936Ff*%(l
_L&n&y1+%
privatestaticint getTotalPage(int everyPage, int Ij;==f~G
rmY,v
totalRecords){ 88 Fb1!a5Z
int totalPage = 0; ntrY =Y
JwN}Jm
if(totalRecords % everyPage == 0) b34zhZ
totalPage = totalRecords / everyPage; :0
W6uFNOU
else +G*"jI8W
totalPage = totalRecords / everyPage + 1 ; &ui:DZAxj|
h|J;6Sm@
return totalPage; tj#=%m?8V;
} m.1LxM$8
<u6c2!I{
privatestaticboolean hasPrePage(int currentPage){ RpHpMtvNo/
return currentPage == 1 ? false : true; 07.nq;/R
} /HB+ami,
u/z,92mmS
privatestaticboolean hasNextPage(int currentPage, @rPI$ia1~
KotPV
int totalPage){ fC=fJZU7$
return currentPage == totalPage || totalPage == #=X)Jx~
I["F+kt^^
0 ? false : true; 8!Wfd)4=,F
} GLo\q:5A
T$: >*
WuBmdjZ
} DBQOxryP>o
*D\0.K,o
Kg4QT/0VA
"V:
~Y\QGuT
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 hmc\|IF`
uQeqnGp
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 %l Q[dXp
I)[`ZVAXR
做法如下: t[%x}0FP-F
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 uK$=3[;U/!
VT'0DQ!NIq
的信息,和一个结果集List: C>AcK#-x,{
java代码: 3Z_t%J5QZ$
VMaS;)0f@
uZ@-e|qto
/*Created on 2005-6-13*/ Bk&-1>cY
package com.adt.bo; YkSuwx@5_q
)\8URc|J
import java.util.List; 3.(.*>
|a%B|CX
import org.flyware.util.page.Page; @XeEpDn]
iwvt%7
/** DLU[<!C
* @author Joa (RExV?:
*/ _B}9f
publicclass Result { ' Q\ @19
+e U`H[iu
private Page page; 3 sl=>;-
R|-6o)$
private List content; {z=j_;<]
P= e4lF.
/** ]Qd{ '}+
* The default constructor b9`i Z
*/ 5bXHz5i
public Result(){ i^R{Ul[
super(); JwjI{,jY
} ~xw5\Y^
\N? 7WQ
/** Yhe+u\vGs\
* The constructor using fields %Mh Q
* 6nc0=~='$
* @param page c!mG1lwD.
* @param content UkZ\cc}aC/
*/ h!v/s=8c
public Result(Page page, List content){ 8qN"3 Et
this.page = page; l^ARW
E
this.content = content; !5&%\NSv
} ~> PgJ^G
`%oIRuYG]j
/** O"\nR:\
* @return Returns the content. H/^B.5RYE>
*/ \04mLIJr9
publicList getContent(){ t}VwVf<K
return content; x)3~il5
} Q{[@`bZB
La9r
/** F;pQ \Y
* @return Returns the page. M'DWu|dIBA
*/ wYjQV?,
public Page getPage(){ 9s(i`RTM
return page; Fom>'g*
} q4k.f_{
\"'\MA
/** }"n7~|
* @param content ;gUXvx~~r
* The content to set. d/]|657u
*/ 'y.JcS!|
public void setContent(List content){ x#mtS-sw2Q
this.content = content; @; ;G88=
} ;%WdvnW
(N0sE"_~I5
/** [x5mPjgw
* @param page {]`p&@
* The page to set. J(e7{aRJ9
*/ H2U:@.o2&
publicvoid setPage(Page page){ U-g9C.
this.page = page; HxIoA
} \2>?6zs
} hVM2/j
4H-j
.|e
6G}c1nWU
.,M;huRg
AF$\WWrB
2. 编写业务逻辑接口,并实现它(UserManager, aMJ;bQD
kiX%3(
UserManagerImpl) .$0Pr%0pWI
java代码: $;`I,k$0>~
c`jDW S
p411 `]Zf
/*Created on 2005-7-15*/
\bold"
package com.adt.service; X;VQEDMPU
M{E{N K
import net.sf.hibernate.HibernateException; k ZxW"2
S-!=NX&C
import org.flyware.util.page.Page; CGZ^hoh/
<lj\#'G3
import com.adt.bo.Result; 3m=2x5{L
`!i-#~n
/** r~>,$[|n})
* @author Joa X;!~<~@Y
*/ /oL8;:m
publicinterface UserManager { 1bSD,;$sQ
P1V1as
public Result listUser(Page page)throws )yj:PY]
78]gtJ
HibernateException; g_q<ze
re`t ]gzb
} Gx'TkU=
iM5vrz`n
<kbyZXV@K
2f,2rW^i
Yb:pAzw6
java代码: .=<$S#x^Hb
8\Hr5FqB(
XUSvhr$|
/*Created on 2005-7-15*/ R#eg^7HfX
package com.adt.service.impl; H l<$a"K7\
LchnBtjn
import java.util.List; zwr\:Hu4
50n}my'2h
import net.sf.hibernate.HibernateException; Z
cpmquf8L
8l>CR#%@C
import org.flyware.util.page.Page; BX< dSK
import org.flyware.util.page.PageUtil; =SBBvnPLI
ln<]-)&C
import com.adt.bo.Result; 8)wt$b
import com.adt.dao.UserDAO; T):SGW
import com.adt.exception.ObjectNotFoundException; "A[ b
rG
import com.adt.service.UserManager; Y*LaBxt Q
c/aup
/** b,<9
* @author Joa I1"MPx{
*/ >M;u*Go`QO
publicclass UserManagerImpl implements UserManager { Cifd21v4
_[K#O,D,
private UserDAO userDAO; 1*Ar{:+ua
n&Yk<
/** k6**u
* @param userDAO The userDAO to set. IL!=mZ>2O
*/ n$["z
w
publicvoid setUserDAO(UserDAO userDAO){ }!s!;BOx
this.userDAO = userDAO; glUo7^ay7
} \a|L/9%
Ee2c5C!|C
/* (non-Javadoc) x\@*60o
* @see com.adt.service.UserManager#listUser )qU7`0'8
Tg
?x3?kw
(org.flyware.util.page.Page) " I+p
*/ jC, FG'P
public Result listUser(Page page)throws
l]_=:)" ]
%NARyz
HibernateException, ObjectNotFoundException { %[QV,fD'E
int totalRecords = userDAO.getUserCount(); 0$P/jt
if(totalRecords == 0) O'DW5hBL0
throw new ObjectNotFoundException W/+K9S25
o>lmst%<
("userNotExist"); \%A%s*1
page = PageUtil.createPage(page, totalRecords); C>QIrZu
List users = userDAO.getUserByPage(page); -yx/7B5@
returnnew Result(page, users); Z)"61)
)
} z1V#'$_5-
adO&