Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 N*J!<vY"
y
{&"g
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 /wt!c?wR
vy:-a G
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 GSHJ?}U,
%pikt7,Z~
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 (8JL/S;Z$
Lek!5Ug
。 *$%ch=
NOC8h\s}(
分页支持类: {RG4 m{#9
v'0WE
java代码: sBN"eHg
QcW6o,
, %8keGhl
package com.javaeye.common.util; LS"_-4I}
s5`CV$bz
import java.util.List; !hMD>B2Z
eo#2n8I>=1
publicclass PaginationSupport { j{8;5 ?x
Th\w#%'N
publicfinalstaticint PAGESIZE = 30; @2yoy&IO
S*aVcyDEP
privateint pageSize = PAGESIZE; 6_G[&
71S~*"O0f
privateList items; <0EVq8h
*5e"suS2
privateint totalCount; ~__r-z
cDkq@H:
privateint[] indexes = newint[0]; <\44%M"iC-
V(lxkEu/Fj
privateint startIndex = 0; 0mt lM(
teQ<v[W.
public PaginationSupport(List items, int OON]E3yy
*KMW6dg;
totalCount){
=,MX%-2
setPageSize(PAGESIZE); QL].)Vgf
setTotalCount(totalCount); jDO"?@+
setItems(items); 2|6E{o
setStartIndex(0); Ihn#GzM?u
} !7rk>YrY
.RazjXAY
public PaginationSupport(List items, int j7(S=
EPd9'9S
totalCount, int startIndex){ )ajF ca@v
setPageSize(PAGESIZE); h!~Qyb>W
setTotalCount(totalCount); v=pkze
setItems(items); bZ5cKQ\6
setStartIndex(startIndex); 6E^h#Ozl
9
} BN_I#8r
nB|m!fi<
public PaginationSupport(List items, int KbXENz&C
4MFdhJoN
totalCount, int pageSize, int startIndex){ IPVD^a?
setPageSize(pageSize); Kggc9^ 7
setTotalCount(totalCount); _c z$w5`
setItems(items); s)A=hB-V
setStartIndex(startIndex); -X]?ql*%`
} o8RVmOXe
fb=[gK#*,
publicList getItems(){ ku3(cb!2
return items; Md*~hb8J
} /bSAVSKR
iBXS
publicvoid setItems(List items){ a_T3<
this.items = items; J<vVsz+7:
} 'kBq@>
dzbFUDJ
publicint getPageSize(){ af>^<q
return pageSize; O0Pb"ou_h.
} V*I2
Pb]EpyAW
publicvoid setPageSize(int pageSize){ { qJ(55
this.pageSize = pageSize; x :? EL)(
} pba`FC4R
J$D/-*/@
publicint getTotalCount(){ _O$7*k
return totalCount; Puq
} )azK&f@tR|
W<c95QD.
publicvoid setTotalCount(int totalCount){ |?gO@?KDZ
if(totalCount > 0){ N<N uBtkA
this.totalCount = totalCount; NI^jQS
M]
int count = totalCount / olxnQYFo
)*`cJ_t
pageSize; fo"%4rkL
if(totalCount % pageSize > 0) -+HD5Hc
count++; )JXlPU
indexes = newint[count];
PKg>|]Rf.
for(int i = 0; i < count; i++){ PNp-/1Cx
indexes = pageSize * >(\Z-I&YQ
lc(}[Z/|V
i; =K;M\_k%y
} (7 O?NS
}else{ 8-s7s!j
this.totalCount = 0; =M ."^X
} ^Z>Nbzr{
} {3qlx1w
-}CMNh
publicint[] getIndexes(){ K[^BRn
return indexes; [r0`D^*=
} `gX$N1(
hRI?>an
publicvoid setIndexes(int[] indexes){ =,J-D6J?
this.indexes = indexes; nr?| !gj
} m85Hx1!p.
~vscATQ
publicint getStartIndex(){ {%BPP{OFk
return startIndex; Yl`)%6'5|
} (&!x2M
(7A- cC
publicvoid setStartIndex(int startIndex){ d",VOhW7)S
if(totalCount <= 0) DEQ7u`6
this.startIndex = 0; *%n(t+'q
elseif(startIndex >= totalCount) /4YxB,
this.startIndex = indexes H{,qw%.|KA
^US ol/
[indexes.length - 1]; >* h3u7t
elseif(startIndex < 0) |0nt u+
this.startIndex = 0; %hVI*p3
else{ ~[Z,:=z
this.startIndex = indexes mO0}Go8
.YlhK=d4
[startIndex / pageSize]; _W
} oqa8v6yG'
} 0]Qk *u<
y7T<Auue`
publicint getNextIndex(){ NI85|*h
int nextIndex = getStartIndex() + :I(d-,C
sEHA?UP$<F
pageSize; X!|K 4Z!k
if(nextIndex >= totalCount) b#W(&b^q
return getStartIndex();
x0||'0I0
else -J;;6aA
return nextIndex; =Bos>;dl
} 7{Zs"d{s
!7n`-#)
publicint getPreviousIndex(){ 6B!v;93U
int previousIndex = getStartIndex() - &R,QJ4L
&W{<Yf9
pageSize; V$g!#V
if(previousIndex < 0) OV/
&'rC
return0; XaH;
else X@\ 9}*9
return previousIndex; oIGF=x,e8
} 5 89P$2e1X
W.^R/s8O%5
} i$6o>V6
B)BR
y%
|e91KmiqJ
Ge ?Q)N
抽象业务类 +ctJV>
java代码: w,-4A
o2x
Sr>5V
U"535<mR
/** ]92=PA>75
* Created on 2005-7-12 >rY^Un{Z
*/ 3
p!t_y|SX
package com.javaeye.common.business; jJV1 /]TJ
D77s3AyHK
import java.io.Serializable; "eIE5h
import java.util.List; TGZr
[
e3WEsD+
import org.hibernate.Criteria; >">grDX
import org.hibernate.HibernateException; ss4YeZa
import org.hibernate.Session; E&;;2
import org.hibernate.criterion.DetachedCriteria; XB<Q A>dLh
import org.hibernate.criterion.Projections; P=m
l;xp
import 9)$gD
H`nd |
org.springframework.orm.hibernate3.HibernateCallback; *})Np0k
import >"[Nmx0;w
\xKhbpO~
org.springframework.orm.hibernate3.support.HibernateDaoS 5Un)d<!7&u
t[:G45].-k
upport; /Zg4JQ~
,VZ<r5NT
import com.javaeye.common.util.PaginationSupport; +@dgHDJ
wg^'oy
public abstract class AbstractManager extends = ,c!V
-/R?D1kOq
HibernateDaoSupport { "DSRy D0M
9P*p{O{_
privateboolean cacheQueries = false; 1"No~/_
I+rLKGZC
privateString queryCacheRegion; fv:&?gc
h]WW?.
publicvoid setCacheQueries(boolean ,p
V3O`z
I^m9(L4%
cacheQueries){ I\f\k>;
this.cacheQueries = cacheQueries; y'_2|5!Qs
} 0Vj!'=Ntv
p:xVi0
publicvoid setQueryCacheRegion(String w|:ev_c|
#kp+e)F
queryCacheRegion){ o`.5NUn
this.queryCacheRegion = %$F_oO7"
X<d`!,bn@
queryCacheRegion; [0H]L{yV
} .[o`TlG%
BOme`0A
publicvoid save(finalObject entity){ ?>q5Abp[
getHibernateTemplate().save(entity); pE6r7
} w
sbzGW~=
,f$ftn\~j/
publicvoid persist(finalObject entity){ r[P+F
getHibernateTemplate().save(entity); }LryRcrD-n
} 2U) 0k*
R(IYb%L
publicvoid update(finalObject entity){ [s F/sa3
getHibernateTemplate().update(entity); Hd{@e6S
}
*z__$!LR
O5ZR{f&
publicvoid delete(finalObject entity){ q{pa _
getHibernateTemplate().delete(entity); Q+dLWFI
} }Io5&ww:U
Is>~ P*2Y=
publicObject load(finalClass entity, U,V+qnS
*rmM2{6
finalSerializable id){ S'=}eeG
return getHibernateTemplate().load 7w.9PNhy
hlGrnL
(entity, id); .Ix[&+LsY
} iu QMVtv
ORhvo,.u
publicObject get(finalClass entity, d?A!0;(*
(f
finalSerializable id){ j`%a2
return getHibernateTemplate().get |b+CXEzo
QW2SFpE
(entity, id); %VS+?4ww
}
M 9KoQS
HJ;!'@
publicList findAll(finalClass entity){ n4 o}}tI
return getHibernateTemplate().find("from 2I{kLN1TY
U3|9a8^H
" + entity.getName()); okH*2F(-
} 0lS=-am
?D=C8[NEX
publicList findByNamedQuery(finalString ]l6niYVB2
s/Q8(sF5
namedQuery){ n W:Bo#
return getHibernateTemplate )F4BVPI
Y,{pG]B$w
().findByNamedQuery(namedQuery); [p_<`gU?
} 2 @t?@,c
$J*lD-h-
publicList findByNamedQuery(finalString query, @gk{wh>c
[n&SA]a
finalObject parameter){ :i*
=s}cv
return getHibernateTemplate ; - 8]
$tDM
U3,W
().findByNamedQuery(query, parameter);
|A#\5u
} Ym
1; /'
V:2{LR<R8
publicList findByNamedQuery(finalString query, 3y yVI#
&S8,-~U
finalObject[] parameters){ ["15~9
return getHibernateTemplate a6 w'.]m
9z7rv,
().findByNamedQuery(query, parameters); HrHtA]
} b&*N
JwdvY]
publicList find(finalString query){ LQJC ]*b1
return getHibernateTemplate().find n= FOB0=
L+_
JKc
(query); O T .bXr~
} U2jlDx4yg
nRcy`A%
publicList find(finalString query, finalObject 5QZ}KNJ|t~
x2tcr+o
parameter){ :\~YbA
return getHibernateTemplate().find 8BX9JoDi
vo^2k13
(query, parameter); K?*p|&Fi?8
} g:Ry.=F7W
4f'!,Q ;
public PaginationSupport findPageByCriteria YtA<4XHU
# aIV\G
(final DetachedCriteria detachedCriteria){ (BIg
return findPageByCriteria -?vVV@W-O^
wLy:S .r
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ];\XA;aOl}
} ="
pNE#
.GIygU_
public PaginationSupport findPageByCriteria co{i~['u
op61-:q/
(final DetachedCriteria detachedCriteria, finalint cq}i)y
cRP!O|I`]
startIndex){ `+@r0:G&v
return findPageByCriteria
>)VWXv0
CQH^VTQ
(detachedCriteria, PaginationSupport.PAGESIZE, -lb%X3`
C#P7@ JE
startIndex); 4tz@?TCb
} Fz2CXC
r:H.VAD
public PaginationSupport findPageByCriteria (1)b> 6
yHn8t]{
(final DetachedCriteria detachedCriteria, finalint qE M,~:lTn
hI,+J>
pageSize, Vsd4;
finalint startIndex){ B* k|NZj
return(PaginationSupport) ?gG%FzfQ/
$'COsiK7
getHibernateTemplate().execute(new HibernateCallback(){ )p[Qj58
publicObject doInHibernate n7hjYNJ
LrdX^_,nt
(Session session)throws HibernateException { 5Vlm?mPU
Criteria criteria = L
|
#"Yn
3V3 q
vd
detachedCriteria.getExecutableCriteria(session); Dp^6|T* HU
int totalCount = "s7}eWM*a
wexa\o
((Integer) criteria.setProjection(Projections.rowCount LknV47vd
,soXX_Y>
()).uniqueResult()).intValue(); h`4!Qv
criteria.setProjection ;$FMOMR
fkD-mRKw
(null); @*iT%p_L
List items = [#+klP$
=H?^G[ y
criteria.setFirstResult(startIndex).setMaxResults cX|(/h,W/
R_b)2FU1y
(pageSize).list(); ZV$!dHW/
PaginationSupport ps = C^*}*hYk$
-+kTw06_C
new PaginationSupport(items, totalCount, pageSize, n\u3$nGL1`
_g6H&no[
startIndex); i7\MVI8
return ps; ;TboS-Y
} 56H~MnX
}, true); oWBjPsQ
} 0r]-Ltvl?}
0[Z wtfL1
public List findAllByCriteria(final U\dLq&=V
Z._%T$8aJv
DetachedCriteria detachedCriteria){ `/9&o;qM
return(List) getHibernateTemplate 4v.i!U#
{
+HoCG;C{
().execute(new HibernateCallback(){ bM"d$tl$?'
publicObject doInHibernate =:m6ge@C&H
ai;- _M+$
(Session session)throws HibernateException { 3q.HZfN~
Criteria criteria = Y/qs\c+
\{ff7_mLo
detachedCriteria.getExecutableCriteria(session); CykvTV Q
return criteria.list(); T*](oA@
} dl+:u}9M$
}, true); LcGG~P|ML
} vue=K
WTUC\}#E\
public int getCountByCriteria(final z
9~|Su
"`
kSI&2
DetachedCriteria detachedCriteria){ ?y,z
Integer count = (Integer) {r:5\
A4Tjfc,rx9
getHibernateTemplate().execute(new HibernateCallback(){ O@-(fyG
publicObject doInHibernate \hZye20
E|x t\*
(Session session)throws HibernateException { )No> Q :t
Criteria criteria = 7|X.E
4']eJ==OH
detachedCriteria.getExecutableCriteria(session); 7&1dr
return l42tTD8Awz
\!zM4ppr
criteria.setProjection(Projections.rowCount ^-%O
8HL8)G6
()).uniqueResult(); tfPe-U
} 4AYW'j C
}, true); sNsWz.DLT#
return count.intValue(); M~5Ja0N~
} &o7"L;
} X"S")BQ
q
I04c7cDp
B }
d+%Rg\v
d ZxrIWx
D()tP
用户在web层构造查询条件detachedCriteria,和可选的 Ummoph7_@
Ev,b5KelD
startIndex,调用业务bean的相应findByCriteria方法,返回一个 5KL??ao-
7rIEpN>*
PaginationSupport的实例ps。 #F ;@Qi3z
j:[#eC
ps.getItems()得到已分页好的结果集 AV;x'H7G
ps.getIndexes()得到分页索引的数组 b.QL\$a
&
ps.getTotalCount()得到总结果数 <O4W!UVg
ps.getStartIndex()当前分页索引 Dj'+,{7,u
ps.getNextIndex()下一页索引 @H8CU!J
ps.getPreviousIndex()上一页索引 =o_zsDv
(gF{S*`
}!jn%@_y@
oC|']r6
U2*kuP+n
)CG,Udu
Us4#O&
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 o=Ia{@
$zJ!L
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 !Er)|YP
6yedl0@wa!
一下代码重构了。 SAokW,
Tr"Bz!
我把原本我的做法也提供出来供大家讨论吧: EsjZ;D,c(
#~`d
;MC
首先,为了实现分页查询,我封装了一个Page类: ejlau#8"
java代码: C*Wyw]:r
AQgm]ex<
t`'5|
/*Created on 2005-4-14*/ mZ#h p}\.
package org.flyware.util.page; !.[H!-V.
,W5!=\Gg(
/** .Tc?PmN
* @author Joa b*<Fi#x1=
* ]ujXPK=t
*/ 6}?5Oy_XF2
publicclass Page { P/T`q:<H
3/EJ^C
/** imply if the page has previous page */ SVqKG+{My
privateboolean hasPrePage; eOs 4c`
@T&w
nk
/** imply if the page has next page */ ;
nYR~~
privateboolean hasNextPage; K# BZ Jcb
QR h %S{
/** the number of every page */ !_+ok$"d
privateint everyPage; &6\f;T4
E\*M4n\!
/** the total page number */ @_Es|(4
privateint totalPage; &eWnS~hJ
;BW9SqlN
/** the number of current page */ xv0y?#`z
privateint currentPage; P7
R}oO_n:
Q=F^Y f
/** the begin index of the records by the current iB3C.wd-
-[xbGSj{
query */ /gq\.+'{
privateint beginIndex; </23*n]
yIqRSqM
yI. hN
/** The default constructor */ Nuc2CB)J
public Page(){ o~ReeZ7)Zg
o3a%u(
} a_k~z3wG
?HP{>l0r
/** construct the page by everyPage K8/I+#j
* @param everyPage QUz_2rN^
* */ j:xm>X'
public Page(int everyPage){ uF<\|y rFt
this.everyPage = everyPage; YL9Tsw
} XrN]}S$N
vfOG(EkG.?
/** The whole constructor */ T,5(JP(h3
public Page(boolean hasPrePage, boolean hasNextPage, *DPKV$
/|,:'W%U
Y!3i3D
int everyPage, int totalPage, oE$zOS&2
int currentPage, int beginIndex){ :}[D;cx
this.hasPrePage = hasPrePage; 9 N9Q#o$!.
this.hasNextPage = hasNextPage; F{F SmUxzK
this.everyPage = everyPage; JwcC9
O
this.totalPage = totalPage; RgLk AHA
this.currentPage = currentPage; JeU1r-i
this.beginIndex = beginIndex; apv"s+
} E
rnGX#@v
4|xQQv
/** f(.t0{Etq
* @return BaOPtBYA:
* Returns the beginIndex. 1JF>0ijU@
*/ %oiA'hz;*
publicint getBeginIndex(){ vz`r
!xj)
return beginIndex; @S?D}myD
} G[\3)@I
GFgh{'|
/** q.v_?X<_
* @param beginIndex ?tf<AZ=+^L
* The beginIndex to set. |eH*Q%M
*/ tz_WxOQ0
publicvoid setBeginIndex(int beginIndex){ 9~yp=JOV@
this.beginIndex = beginIndex; a\Dw*h?b~
} I_On0@%T5b
bh UghHT
/** ;#S4$wISw`
* @return !E9A=u{
* Returns the currentPage. jQY^[A
*/ 4L)Ox;6>
publicint getCurrentPage(){ !k=~a]
return currentPage; -ZBSkyMGy
} W Z^u%Z
+3k#M[Bn}
/** wPH1g*U
* @param currentPage 5c-'m?k
* The currentPage to set. *","u;&
*/ <77v8=as5
publicvoid setCurrentPage(int currentPage){ ,=y8[(h
this.currentPage = currentPage; UjH+BC+9`b
} }7Y@u@R
Df=zrs["
/** A3zO&4f
]
* @return
`sJv?
* Returns the everyPage. n^k Uu2g|
*/ x).`nZ1
publicint getEveryPage(){ %y R~dt'
return everyPage; ^li(q]g1!
} ~:):.5o
5vj tF4}7!
/** xZp`Ke!
* @param everyPage 7G9o%!D5
* The everyPage to set. o]m56
*/ BV6
U -
publicvoid setEveryPage(int everyPage){ LKI2R_|n
this.everyPage = everyPage; 'tun;Y
} p$bR M`R&s
;Ak 6*Sr
/** 6%2\bI.#
* @return )}5f'TK
* Returns the hasNextPage. c9axzg
UA
*/ n]J;BW&Av
publicboolean getHasNextPage(){ 7wwlZ;w
return hasNextPage; !-Md+I_
} n<66 7
<
,: 4+hJ<q
/** C}cYG
* @param hasNextPage R#33ACCX
* The hasNextPage to set. F)4;:".zna
*/ S9@)4|3C|p
publicvoid setHasNextPage(boolean hasNextPage){ h,)UB1
this.hasNextPage = hasNextPage; =1h> N/VJ
} OQa;EBO
-H
AUKY@;5
/** HLp'^
* @return S`Wau/7t
* Returns the hasPrePage. GXx/pBdy[4
*/ iJ 8I#
j+N
publicboolean getHasPrePage(){ \[;Qqn0
return hasPrePage; ]^?V8*zL]
} b1frAA
^+q4* X6VB
/** 8WL*Pr1I
* @param hasPrePage o9L$B
* The hasPrePage to set. u4;#~##
*/ {_1zIt|
publicvoid setHasPrePage(boolean hasPrePage){ (S#nA:E
this.hasPrePage = hasPrePage; 7T-}oNaJA\
} Wf!<Qot|R#
d@,3P)?
/** &P3ep[]j
* @return Returns the totalPage. Y"Y+U`Qt
* Pg/$N5->
*/ zoI0oA
publicint getTotalPage(){ 9Z;"9$+M
return totalPage; QX&1BKqWn
} coFQu ;i
osW"b"_f
/** a gM I$
* @param totalPage ;,F:.<P
* The totalPage to set. CXfPC[o
*/ 3QO*1P@q
publicvoid setTotalPage(int totalPage){ ql
c{k/
u
this.totalPage = totalPage; f+j-M|A
} (DrDWD4_
~q05xy8
} /E0/)@pDq
)#_:5^1
qLh[BR
(L7@ez
Z=\wI:TY1
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 @8qo(7<~Q
IL2OVL X
个PageUtil,负责对Page对象进行构造: J|GEt@o3
java代码: NgPY/R>
1>e%(k2w%
(&t8.7O
/*Created on 2005-4-14*/ ]@bu%_s"
package org.flyware.util.page; @-F[3`HeA
?v$kq}Rg
import org.apache.commons.logging.Log; ~G*eJc0S:
import org.apache.commons.logging.LogFactory; /QK H30E
\" W_\&X
/** Bfz]PN78.G
* @author Joa [_SV$Jz
* wSP'pM{#2
*/ 0?d}Oj
publicclass PageUtil { 5u3SP?.&
qD/X% `>Q
privatestaticfinal Log logger = LogFactory.getLog .B|a.-oA4
M<"H1>q@
(PageUtil.class); e[AwR?=
xfJ&11fG2
/** bTN0 n
* Use the origin page to create a new page TScI_8c>
* @param page 7o5~J)qIC
* @param totalRecords JK@"
&
* @return (D5.NB%@
*/ _pS!sY~d
publicstatic Page createPage(Page page, int 7y2-8eL
L-v-KO6
totalRecords){ c (Gl3^
return createPage(page.getEveryPage(), Q!_@Am"h
mfpL?N
page.getCurrentPage(), totalRecords); _wM YA8n
} pJpTOq\h
rAZsVnk?
/** cw)'vAE
* the basic page utils not including exception ubvXpK:.
C-6m[W8S
handler 4RXF.kJ3=
* @param everyPage 5? rR'0
* @param currentPage 3"XS#~l%
* @param totalRecords V0!.>sX9
* @return page A(<"oAe|
*/ AJ`R2
$
publicstatic Page createPage(int everyPage, int |?KdQeL
h-`*S&mZ
currentPage, int totalRecords){ WOaj_o
everyPage = getEveryPage(everyPage); hd E? %A
currentPage = getCurrentPage(currentPage); g Q@fe3[
int beginIndex = getBeginIndex(everyPage, [hT|]|fJS;
o/Cu^[an
currentPage); -WX{y Ci
int totalPage = getTotalPage(everyPage, ?6[X=GeUs
c3NUJ~>=y
totalRecords); p0S;$dH\D
boolean hasNextPage = hasNextPage(currentPage, D+:} D*_&
t/HUG#W{
totalPage); %ymM#5A
boolean hasPrePage = hasPrePage(currentPage); j%y)%4F8
yA#-}Y|]b
returnnew Page(hasPrePage, hasNextPage, oA1d8*i^E
everyPage, totalPage, 6%&RDrn
currentPage, U;Ne"Jh
Q:4euhz*
beginIndex); qr~=S
} MJ+]\(
,9:0T LLR
privatestaticint getEveryPage(int everyPage){ `p.O
return everyPage == 0 ? 10 : everyPage; k}o*=s>M
} IT~pp_6g
8aSH0dX
privatestaticint getCurrentPage(int currentPage){ T)QT_ST.9
return currentPage == 0 ? 1 : currentPage; EhBYmc"&
} p*^[
~} N
F;&a=R!.
privatestaticint getBeginIndex(int everyPage, int DY~zi
~Uet)y<
currentPage){ 9J!@,Zsh
return(currentPage - 1) * everyPage; 5U3b&0
} QNzx(IV@
-#ta/*TT:
privatestaticint getTotalPage(int everyPage, int 8eVQnp*
HAi'0%"
totalRecords){ C"We>!
int totalPage = 0; Ehv*E
'n)]"G|
if(totalRecords % everyPage == 0) z'FJx2
totalPage = totalRecords / everyPage; ys3&$G
else Wr%E}mX-
totalPage = totalRecords / everyPage + 1 ; iq!u}# x_
07?| "c.
return totalPage; /4f4H?A -
} l]GUQcN=
?z2k74&M^
privatestaticboolean hasPrePage(int currentPage){ Rf~? u)h1
return currentPage == 1 ? false : true;
oq>8
} xqua>!mqS
{{\
d5CkX
privatestaticboolean hasNextPage(int currentPage, pM^r8kIH
zeZ}P>C
int totalPage){ r^$4]@Wn
return currentPage == totalPage || totalPage == F5#P{zk|
9Fkzt=(E~
0 ? false : true; :&/b}b!)AX
} *
@QC:1k
/4R|QD
?5> Ep:{+/
} 'z=QV {ni
Y_}DF.>I P
1gZW~6a}
5ecAev^1-
TZ]D6.mD
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 }4; \sY
j/FFxlFNL
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 o$=D`B
.-6B6IEI_"
做法如下: >$.lM~k
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 LJ+fZ
N
@\=%M^bx
的信息,和一个结果集List: HZ#<+~J
java代码: f_&bwfbo
{y[T3(tt
k365.nc
/*Created on 2005-6-13*/ \*C}[D
package com.adt.bo; $
+`
Xiyh3/%yy
import java.util.List; jE!W&0
Q+O3Wgjy
import org.flyware.util.page.Page; !H5r+%Oo|
`qjiC>9
/** vPV=K+1
* @author Joa q0oNRAvn"
*/ 1i.t^PY
publicclass Result { <R6$ kom`
Rw54`_kFEB
private Page page; t/= xY'7
UY_'F5X
private List content; !1:364
~vVsxC$.
/** R9/(z\'}
* The default constructor `xO9xo#
*/ hY?x14m$3
public Result(){ o+H;ZGT5H
super();
{ws:g![
} -L&FguoVB
U-P\F-
/** gUoL8~
* The constructor using fields Sc<%$ Gd
* {~"&$DY2
* @param page 7h4"5GlO0
* @param content 03iD(,@
*/ eQ}o;vJN
public Result(Page page, List content){ &J\V
!uVo
this.page = page; *}t,:N;i
this.content = content; )1KlcF
} JVzU'd;1!
]"3(UKx
/** @bN`+DC!<
* @return Returns the content. H$
!78/f
*/ v Kzq7E
publicList getContent(){ O6LuFT.
return content; #'qEm=%
} USKa6<:{W
2qb,bp1$
/** ;xnJ+$//U
* @return Returns the page. kp~@Ub
@O3
*/ wX3x.@!:
public Page getPage(){ Z;^UY\&X
return page; A
'Q
nL
} >g+ogwZ
xwwy9:ze*l
/** J~0_
* @param content >-s\$8En'
* The content to set. *Ge2P3
*/ D(MolsKc?
public void setContent(List content){ ?lh
`>v
this.content = content; pZu2[
} pq"3)+3:
,qj
/** !+?,y/*5(
* @param page ,FvBZ.4c3=
* The page to set. :
kVEB<G
*/ .c[v /SB]
publicvoid setPage(Page page){ : -@o3Syg
this.page = page; ^K4#_H#"
} r@_`ob RW;
} aj1o
>Lh+(M;+F
'J&&