Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 lO^Ly27
^3~+| A98M
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ((KNOa5
bm/pLC6%.
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 cyYsz'i m
X S:W{tL!
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Tx+!D'>
"rxhS;
R1>
。 /mS|Byx
kpF")0qr
分页支持类: %LI[+#QE
z}Y23W&sX
java代码: i;:gBNmo=
5Bwr\]%$P
/~sNx
package com.javaeye.common.util; A'A5.\UN
&lbZTY}
import java.util.List; ^eF%4DUC;
War<a#0
publicclass PaginationSupport { bUv}({
yg}zK>j^vC
publicfinalstaticint PAGESIZE = 30; Ug :3)q[O
_FpZc?=
privateint pageSize = PAGESIZE; 8+}yf.`
RbOEXH*]
privateList items; <4lR
B=<>OYH
privateint totalCount; 9, A(|g
=*paa
privateint[] indexes = newint[0]; +M )ep\j
(L`7-6e(Ab
privateint startIndex = 0; 18`YY\u(
Myj5qh
public PaginationSupport(List items, int 5(9SIj^O
C8^h`B9z&I
totalCount){ r'|V z*/h
setPageSize(PAGESIZE); d6(R-k#B
setTotalCount(totalCount); kmNa),`{s
setItems(items); ^Om0~)"q
setStartIndex(0); \xCI8 *W
} ?=u/&3Cw
]o!rK<
public PaginationSupport(List items, int nK!yu?mS
e6G=Bq$
totalCount, int startIndex){ c#)!-5E~H
setPageSize(PAGESIZE); ,)&ansN
setTotalCount(totalCount); r6,EyCWcCs
setItems(items); I,7~D!4G
setStartIndex(startIndex); +,;"?j6<p
} )Cas0~ RM
c<k=8P
public PaginationSupport(List items, int \@\r`=WgB
2wCSjAWWh(
totalCount, int pageSize, int startIndex){ JD\yl[ac%
setPageSize(pageSize); cWp5' e]A
setTotalCount(totalCount); W;Pdbf"
setItems(items); 3VI[*b
setStartIndex(startIndex); Fx@ovI- 5
} g?7I7W~?`
7LFJi@*8
publicList getItems(){ F.rNh`44
return items; OM>,1;UH]
} YLXLaC[
A{Kc"s4fO
publicvoid setItems(List items){ :.VI*X:aQh
this.items = items; V
yOuw9
} @Sr{6g*I
b(E}W2-t
publicint getPageSize(){ ^uWPbW&/q
return pageSize; Ux/|D_rlf
} lmGVSdo
hSN{jl{L`
publicvoid setPageSize(int pageSize){ 5SB!)F]
this.pageSize = pageSize; R^p'gQc$
} \X*Es.;|x
mRurGaR
publicint getTotalCount(){ k4C3SI*`4
return totalCount; 3-=f@uH!
} &g;&=<#I
;c/|LXc\
publicvoid setTotalCount(int totalCount){ pftnFOLO
if(totalCount > 0){ $q$G
this.totalCount = totalCount; X_3*DqY
int count = totalCount / -n:~m
p
AT:L&~O.
pageSize; "^froQ{"T
if(totalCount % pageSize > 0) ia9=&Hy])
count++; z [|:HS&
indexes = newint[count]; 2iWSk6%R
for(int i = 0; i < count; i++){ 74w Df
indexes = pageSize * cj64.C
= :/4)
i; x]Pp|rHj
} >eC>sTPQ{
}else{ \PzJ66DL!
this.totalCount = 0; *HONA>u
} hl/) 1sOIR
} F HK{cE
A3uF 0A
publicint[] getIndexes(){ hEh` cBO
return indexes; %&5PZmnW
} /g]NC?
K\trT!I
publicvoid setIndexes(int[] indexes){ w-j^jU><3
this.indexes = indexes; L-9AJk>V
} c%+_~iBUN
tH)fu%:p
publicint getStartIndex(){ <G_71J`MLC
return startIndex; zk;'`@7
} w paI}H#
sU$<v( `"
publicvoid setStartIndex(int startIndex){ mB5Sm|{
if(totalCount <= 0) ufi:aE=}
this.startIndex = 0; 5%jy7)8C
elseif(startIndex >= totalCount) n~Yr`5+Z
this.startIndex = indexes rj
] ~g
<r1/& RW,
[indexes.length - 1]; c;B: o
elseif(startIndex < 0) v,L@nlD]
this.startIndex = 0; T!jMh-8
else{ 3sK^
(
this.startIndex = indexes ?u4t;
'lMDlTU O
[startIndex / pageSize]; P!yOA_)as
} Y-s6Z\
} Yh["IhjR
jX;$g>P
publicint getNextIndex(){ nZX`y
-AZ
int nextIndex = getStartIndex() + 96d&vm~m1
Z VyJ%"(E
pageSize; s/0bXM$^
if(nextIndex >= totalCount) pV(qan,
return getStartIndex(); ,@]*Xgt=
else v8y !zo'
return nextIndex; 3^,p$D<T:,
} 0aqq*e'c
U1)!X@F{
publicint getPreviousIndex(){ =&" a:l
int previousIndex = getStartIndex() - ,ll<0Atg
bIXD(5y
pageSize; RgD %pNhI
if(previousIndex < 0) 3(,c^F
return0; $Xr4=9(|7
else ;r BbLM`
return previousIndex; FmhT^
} s>I~%+V.?:
W) ?s''WE;
} FvXpqlp
n#S?fsQN
{rzvZ0-j}
"H\R*\-0
抽象业务类 B.4Or]
java代码: _&RGhA
fP/;t61Z
w&>*4=^a
/** #OwxxUeZ
* Created on 2005-7-12 wD92Ava
*/ +TC##}Zmb
package com.javaeye.common.business; Rjn%<R2nW
0C4Os p
import java.io.Serializable; b=kY9!GN,v
import java.util.List; L>n^Q:M
"#8I &xZK
import org.hibernate.Criteria; zXW;W$7V4
import org.hibernate.HibernateException; T}jW,Ost
import org.hibernate.Session; MP
p
import org.hibernate.criterion.DetachedCriteria; ujLje:Yc
import org.hibernate.criterion.Projections; l:OXxHxRi
import o0_H(j?
]zz%gZz
org.springframework.orm.hibernate3.HibernateCallback; )Vo%}g?6!
import i8!err._
XZ"oOE0=
org.springframework.orm.hibernate3.support.HibernateDaoS TMD*-wYr
uBw[|,yn2*
upport; -FS!v^
F8&L'@m9>
import com.javaeye.common.util.PaginationSupport; zbJ}@V
]Na; b
public abstract class AbstractManager extends cv_t2m
: cPV08i
HibernateDaoSupport { fS3%
I2gSgv%
privateboolean cacheQueries = false; J4Ca0Ag
m A('MS2
privateString queryCacheRegion; wlDo(]mj=O
8:U0M'}u>
publicvoid setCacheQueries(boolean epI~w
o QR?H
cacheQueries){ t!59upbN}3
this.cacheQueries = cacheQueries; .M s$)1
} Rl'xEtaN
xLP8*lvy
publicvoid setQueryCacheRegion(String 24*3m&fA*K
#n+sbx5~7
queryCacheRegion){ Of#"nu
this.queryCacheRegion = b?/Su<q
\[
W`hhJ
queryCacheRegion; 1
J[z ![Tf
} @9lGU#
~FVbL-2
publicvoid save(finalObject entity){ L+Gi
getHibernateTemplate().save(entity); uT
Y G/O
} p2gu@!
0zk054F'
publicvoid persist(finalObject entity){ cqp^**s
getHibernateTemplate().save(entity); 9t7 e~&R
} ?lm<)y?I7+
;x&3tN/I
publicvoid update(finalObject entity){ jX,A.
getHibernateTemplate().update(entity); c^R "g)gr
} `(]mUW
ceLr;}?Ws
publicvoid delete(finalObject entity){ PiLLUyQx
getHibernateTemplate().delete(entity); (L!u[e0[#
} ;L,yJ~
lUiO |
publicObject load(finalClass entity, `FK qVd
eGUe#(I /
finalSerializable id){ o3`0x9{
return getHibernateTemplate().load d>/4z#R}-
_I%mY!x\`
(entity, id); r#d]"3tH
} Xy9'JVV6
h1#l12k^'
publicObject get(finalClass entity, U+uIuhz
OA7=kH@3c
finalSerializable id){ ~]BR(n
return getHibernateTemplate().get )+.AgqxI
M#yUdl7d
(entity, id); qJ$S3B
} R%JEx3)0m
USXPa[
publicList findAll(finalClass entity){ BbI),iP
return getHibernateTemplate().find("from }dSFv
Y5TBWcGU%
" + entity.getName()); (CE2]Nv9")
} .yb8<q s
tfv@
)9
publicList findByNamedQuery(finalString fVq,?
XX*f
namedQuery){ 0qBXL;sE
return getHibernateTemplate M+4S >Sjw
M<@9di7c
().findByNamedQuery(namedQuery);
K4^B ~0~
} ?hW(5]p|
lb]k"L%KU7
publicList findByNamedQuery(finalString query, Lya?b
^fM=|.?
finalObject parameter){ CF5%&B
return getHibernateTemplate ;8gODj:dO
b{W ,wn
().findByNamedQuery(query, parameter); K=2j}IPe
} }80n5X<9
V{0 V/Nv
publicList findByNamedQuery(finalString query, 7wqD_Xr
Z8pZm`g)T
finalObject[] parameters){ Kw>gg
return getHibernateTemplate E}]SGU"
_xdttO^N
().findByNamedQuery(query, parameters); ;~s@_}&
} 73M;-qnU
*kDV ^RBfq
publicList find(finalString query){ Q1
vse
return getHibernateTemplate().find j MA%`*r
_[
`"E'
(query); 98WJ"f_ #
} <zu)=W'R]
F,XJGD*
publicList find(finalString query, finalObject 9a.[>4}
BCHI@a
parameter){ @HXXhYH
return getHibernateTemplate().find %$!EjyH9
yNQ 9~P2
(query, parameter); ^[zF IO
} l1RFn,Tzr
{K2F(kz?T
public PaginationSupport findPageByCriteria ,@2d4eg4
< YuI}d~'
(final DetachedCriteria detachedCriteria){ \y/+H
return findPageByCriteria W/;qMP1"-
+z\O"zlj
(detachedCriteria, PaginationSupport.PAGESIZE, 0); .]Z,O>N
} {c$%3iQq
fGLOXbsA
public PaginationSupport findPageByCriteria .{]=v
R7By=Y!t
(final DetachedCriteria detachedCriteria, finalint 0M>%1*
lc0Z fC
startIndex){ Y'%_--
return findPageByCriteria ^F1zkIE
mH3{<^Z6
(detachedCriteria, PaginationSupport.PAGESIZE, >JhIRf
=j~}];I
startIndex); or]s
} sfNAGez
m;I;{+"u
public PaginationSupport findPageByCriteria <kor;exeJ
+<I1@C
(final DetachedCriteria detachedCriteria, finalint O~&l.>??
/h%MWCZWm^
pageSize, :hxZ2O?5_
finalint startIndex){ @)8C
return(PaginationSupport) }~5xlg$B<<
K#{E87G(
getHibernateTemplate().execute(new HibernateCallback(){ %x7l`.)N
publicObject doInHibernate 8JAT2a61ur
`24:Eg6r
(Session session)throws HibernateException { N,_ej@L8
Criteria criteria = y/2U:H
'lNl><e-
detachedCriteria.getExecutableCriteria(session); HM1y$ej
int totalCount = yQ8H-a.
4B}w;d@R
((Integer) criteria.setProjection(Projections.rowCount P6 G/J-
Dy^4^ J5+
()).uniqueResult()).intValue(); ]R{=|
criteria.setProjection 2=NYBOE
zR3Z(^]v
(null); _mL 9G5~r
List items = wh:`4Yw
`\P :rn95;
criteria.setFirstResult(startIndex).setMaxResults Y<.F/iaH
Ic&t_B*i}]
(pageSize).list(); "$8<\k$LGT
PaginationSupport ps = et ]*5Y6
;3sT>UB
new PaginationSupport(items, totalCount, pageSize, U^0vLyqW^5
.< vg[
startIndex); 7\U1K^q
return ps; /ADxHw`k
} {UZli[W1
}, true); h?YjG^'9
} TJ5{Ee GV
emS +%6U
public List findAllByCriteria(final k*c:%vC!
[I4FU7mpH
DetachedCriteria detachedCriteria){ MgMLfgt"V
return(List) getHibernateTemplate U w`LWG3T
y!!+IeReS
().execute(new HibernateCallback(){ xD?{Hw>QT#
publicObject doInHibernate N<> dg
_zmx
(Session session)throws HibernateException { d8RpL{9\7
Criteria criteria = 83l)o$S
Z#o\9/{(R
detachedCriteria.getExecutableCriteria(session); iK%Rq
return criteria.list(); c8"I]Qc7
} r IK|} 5
}, true); ZJ[ Uz_%W
} nLfnikw&
*E)Y?9u"
public int getCountByCriteria(final }5tn
AYZds >#Q
DetachedCriteria detachedCriteria){ -6tF
Integer count = (Integer) rw\4KI@ L
H@j ^,
getHibernateTemplate().execute(new HibernateCallback(){ b);}x1L.T
publicObject doInHibernate o"1us75P
}lb.3fqiA
(Session session)throws HibernateException { \+AH>I;vO
Criteria criteria = 5PL,~Y
n
~3c<{coZ
detachedCriteria.getExecutableCriteria(session); YKc{P"'/|
return \!V6` @0KC
xBG1up<z
criteria.setProjection(Projections.rowCount dw4)4_
+tN-X'u##
()).uniqueResult(); uATBt
} (P>vI'
}, true); +%Gm2e;_u
return count.intValue(); gwYd4
} e #OU {2X
} [1UqMkXtf
Nb9pdkf0
x+TNF>%'D
!aEp88u
V7@xr
M
zn~m;0Xi
用户在web层构造查询条件detachedCriteria,和可选的 v1lj /A
P%lLKSA
startIndex,调用业务bean的相应findByCriteria方法,返回一个 T?ZMmUE
6e*b;{d
PaginationSupport的实例ps。 /(0d{
_/=ZkI5
ps.getItems()得到已分页好的结果集 N_DgnZ7*
ps.getIndexes()得到分页索引的数组 7f$Lb,\y
ps.getTotalCount()得到总结果数 5~X%*_[],
ps.getStartIndex()当前分页索引 d#tUG~jc
ps.getNextIndex()下一页索引 M:SxAo-D2
ps.getPreviousIndex()上一页索引 09?<K)_G
?hu 9c
O&s6blD11
X>6a@$Mx P
_#F'rl6'
4>E2G:
*3K"Kc2
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~GeYB6F
,'673PR
,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 FS}z_G|4]
)-{Qa\6(%
一下代码重构了。 MnI $%
L' pZ
我把原本我的做法也提供出来供大家讨论吧: ({9!P30:
7| T:TbY>
首先,为了实现分页查询,我封装了一个Page类: ^Bb_NcU
java代码: HW G~m:km
S_CtEM
vSA%A47G
/*Created on 2005-4-14*/ 8#Z5-",iw
package org.flyware.util.page; /fq6-;co+
PS22$_}
/** ("oA{:@d
* @author Joa 0R]CI
* bsry([N>w
*/ XL3h ;$,
publicclass Page { z&0V21"l
f.$o|R=v
/** imply if the page has previous page */ z)~!G~J]
privateboolean hasPrePage; +;Gl>$
~e+w@ lK
/** imply if the page has next page */ Q=8
cBRe
privateboolean hasNextPage; u3:Q t2^S
,')bO*Ng
/** the number of every page */ -!cAr
<
privateint everyPage; b9N4Gr
o%%fO
/** the total page number */ ^!qmlx*
privateint totalPage; 0)]1)z(P
>i%w'uU
/** the number of current page */ | dwxea
privateint currentPage; VWv0\:,G
? ^CGJ1
/** the begin index of the records by the current 72zuI4&
A%1=6
query */ MGzF+ln^U
privateint beginIndex; V2,WP
n y)P
YMTA`T(+
/** The default constructor */ ([-=NT}Aq
public Page(){ syf"{bBe
,`zRlkX
} WN#lfn8 7
#L0I+ K,K\
/** construct the page by everyPage K, 5ax@
* @param everyPage /AW>5r]
* */ B7MW" y
public Page(int everyPage){ ] <3?=$
this.everyPage = everyPage; }GDG$QI]K&
} !nq\x8nU
0Zh
_Q
/** The whole constructor */ 8M9\<k6
public Page(boolean hasPrePage, boolean hasNextPage, ^&H=dYcV>/
A'1AU:d
R?~h7 d
int everyPage, int totalPage, \]A;EwC4C
int currentPage, int beginIndex){ _vV&4>
this.hasPrePage = hasPrePage; vqOLSE"t*O
this.hasNextPage = hasNextPage; ~!F4JRf
this.everyPage = everyPage; 5I1J)K;
this.totalPage = totalPage; \{zAX~k6
this.currentPage = currentPage; bV*zMoD#
this.beginIndex = beginIndex; A9Wqz"[
} vfUfrk@D~
Gc!8v}[7J
/** <]^;/2.B
* @return :V~*vLvR
* Returns the beginIndex.
c dbSv=r
*/ dMmka
publicint getBeginIndex(){ -QPWi2:k
return beginIndex; u7&'3 ef
} 5MY}(w
;nKHm
/** B8AzN9v&"N
* @param beginIndex SM+fG: 4d
* The beginIndex to set. kdh9ftm*\
*/ @1?]$?u&
publicvoid setBeginIndex(int beginIndex){ (Q8?)
this.beginIndex = beginIndex; |p -R9A*>h
} OsL%SKs|
Vnj/>e3
/** *X
l<aNNx
* @return }FiN 7#
* Returns the currentPage. ,i?!3oLT
*/ :n9xH
publicint getCurrentPage(){ KzX
,n_`an
return currentPage; E(!6n= qR
} Z#6~N/b
C%_
/** (}1v^~FXj
* @param currentPage - (_e=3$
* The currentPage to set. p?$G>nkdq
*/ R:OU>HsdX
publicvoid setCurrentPage(int currentPage){ } .3]
this.currentPage = currentPage; QrckTO
} `XSc >
Lp`<L -s
/** xGEmrE<;
* @return ^]qV8
* Returns the everyPage. OZ'.}((?n
*/ M2E87w
publicint getEveryPage(){ vk)0n=
return everyPage; 2"+x(Ax
} =ym
4^[}]'w
/** aaz"`,7_
* @param everyPage +'['HQ)
* The everyPage to set. |@ZqwC=
*/ (#B^Hyz!
publicvoid setEveryPage(int everyPage){ 6{ +_T
this.everyPage = everyPage; }u-S j/K
} lIVxW+
w"a 9'r
/** L;S*.Ol>
* @return HIX=MprL<
* Returns the hasNextPage. )'!ml
*/ ?S@R~y0K
publicboolean getHasNextPage(){ P,/13tZ#3
return hasNextPage; } }f_
} 2rO)qjiH
M*O(+EM
/** IQw
%|^
* @param hasNextPage 974eY
* The hasNextPage to set. PPCTc|G
*/ Q&upxE4-~
publicvoid setHasNextPage(boolean hasNextPage){ <DXmZ1
this.hasNextPage = hasNextPage; D#d8 ^U
} tCbr<Ug
0ck&kpL:9
/** eMN+qkvH
* @return Wg`+u
* Returns the hasPrePage. L7Qo-
*/ =s0g2Zv"\
publicboolean getHasPrePage(){ pfL2v,]g
return hasPrePage; r}R^<y@I
} dqD;y#/
8K.s@<
/** oE!hF }O
* @param hasPrePage }0BL0N`_
* The hasPrePage to set. cB ab2/
*/ 8lOZIbwS
publicvoid setHasPrePage(boolean hasPrePage){ ..jq[(;N
this.hasPrePage = hasPrePage; 8B *E+f0
} x/%7%_+'
rkfQr9Vc
/** 9V=<| 2
* @return Returns the totalPage.
8>Du
* /[Bl
*/ }%!FMXe
publicint getTotalPage(){ Lf^5Eo/
5A
return totalPage; (Bt;DM#>
} .'5'0lR5
8Wdkztp/S
/** ~VqFZasV
* @param totalPage yX7CN5vVl
* The totalPage to set. }c`
?0FQ
*/ (B>)2: T1
publicvoid setTotalPage(int totalPage){ TRgY :R_
this.totalPage = totalPage; M8^.19q;
} F2bm+0vOJ
e86Aqehle
} 'bB>$E
Mx/h?}u;
$ yDW.pt
1Q&cVxA"\
tLS<0
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 E\R raPkQT
Z!wD~C"D73
个PageUtil,负责对Page对象进行构造: /rIm7FW)
java代码: yy1>r }L
<G\
<QV8W
6sYV7w,'@
/*Created on 2005-4-14*/ |x d@M-ln
package org.flyware.util.page; cP*c(k~N
:
cFF
import org.apache.commons.logging.Log; rD0k%-{{
import org.apache.commons.logging.LogFactory; M MAAHo
?_VRfeztw
/** _Fy4DVCg
* @author Joa #04{(G|~+E
* ,'FD}yw4v
*/ $Q8P@L)[
publicclass PageUtil { k(zs>kiP
GhqgRzX
privatestaticfinal Log logger = LogFactory.getLog
*-9# /Cp
T$H2'tK|
(PageUtil.class); Rr+qgt;f5
=LXvlt'Q34
/** `]K,'i{R
* Use the origin page to create a new page ;c>>$lr
* @param page 6RH/V:YY
* @param totalRecords + jp|Y?6Z
* @return gWFL
*/ UskZ%J
publicstatic Page createPage(Page page, int /GsSrP_?]
}US7Nw
totalRecords){ uyL72($
return createPage(page.getEveryPage(), &}zRH}s;
w`M]0'zls
page.getCurrentPage(), totalRecords); OYBotk]{1
} M'^(3#ZU
C0zrXhY_v
/** @(i*-u3Tq
* the basic page utils not including exception jZrY=f
+``>,O6
handler :tKbz
nd/
* @param everyPage ZR1+
O8
* @param currentPage LPq2+:JpS
* @param totalRecords DXKyRkn6e
* @return page /ca(a\@R
*/ h=hoV5d@
publicstatic Page createPage(int everyPage, int DeA @0HOxh
}g}6qCv7
currentPage, int totalRecords){ 3nwz<P
everyPage = getEveryPage(everyPage); !loO%3_)
currentPage = getCurrentPage(currentPage); ]a)IMIh;
int beginIndex = getBeginIndex(everyPage, =Q@6c
yHl@_rN
sC
currentPage); M6\7FP6G
int totalPage = getTotalPage(everyPage, @|^jq
Z%Vr+)!4
totalRecords); ?hKm&B;d
boolean hasNextPage = hasNextPage(currentPage, 6%>/og\%
_~ v-:w
totalPage); w-lrnjs
boolean hasPrePage = hasPrePage(currentPage); ^Ss<X}es-
yP
x\ltG3
returnnew Page(hasPrePage, hasNextPage, 2.]~*7
everyPage, totalPage, P!5Z]+B#
currentPage, AQ-mE9>P
^ b@!dS
beginIndex); ?F1wh2oq
} "s% 686Vz
BjYOfu'~z
privatestaticint getEveryPage(int everyPage){ H;qJH1EdD
return everyPage == 0 ? 10 : everyPage; )+?HI^-[S
} 0"TgLd
Y7-*2"!
privatestaticint getCurrentPage(int currentPage){ 4*iHw+%mq
return currentPage == 0 ? 1 : currentPage; 9-b 8`|s
} R^w}o,/
$cq!RgRn
privatestaticint getBeginIndex(int everyPage, int 7iP5T
?C}sR: K/
currentPage){ ^ZR8s^X
return(currentPage - 1) * everyPage; O"qR }W
} ):S!Nl
2pz4rc
privatestaticint getTotalPage(int everyPage, int $1~c_<DN
uw_H:-J
totalRecords){ =w6}\ 'X
int totalPage = 0; L/)B}8m\
*y{+W
if(totalRecords % everyPage == 0) V+46R
]
totalPage = totalRecords / everyPage; `6P?G|'
else J8J!#j.
totalPage = totalRecords / everyPage + 1 ; w3d34*0$
^eobp.U
return totalPage; |Hfl&3
} =C#*!N73
G&jZ\IV
privatestaticboolean hasPrePage(int currentPage){ a/34WFC
return currentPage == 1 ? false : true; 5.dl>,
} KhrFg1|
*(icR
privatestaticboolean hasNextPage(int currentPage, b )Tl*
>zFD$
int totalPage){ B_cgWJ*4
return currentPage == totalPage || totalPage == :Z[(A"dA
~U9q-/(J/
0 ? false : true; 4Ppop
} &;s<dDQK
};^}2Xo+
]'tJ
S]
} 4b=Gg
\KCWYi]
N2T&,&,t
YIO.yN"0
'^DUq?E4
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~#%&
W1hX?!xp!
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 -n-Z/5~ X
"
<Qm
-
做法如下: s@PLS5d"
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 QypZH"Np
\ZsP]};*
的信息,和一个结果集List: 2
^oGwx @
java代码: Wa<-AZnh
9ZhDZ~)p,
gX_SKy
/*Created on 2005-6-13*/ ]hL:33
package com.adt.bo; a}dw9wU!:
L@?e:*h
import java.util.List; V,m3-=q
q=+wI"[
import org.flyware.util.page.Page; %W&1`^Jl
"Vx6 #u@}
/** 6`Lcs
* @author Joa >O3IfS(l
*/ V,vc_d?,_o
publicclass Result { Bh,Q8%\6
vbaC+AiX
private Page page; [Teh*CV
>e/ r2U
private List content; z>p]/Sa
++0rF\&
/** )T/J
* The default constructor Zt_r9xs>
*/ 5x2L(l-2
public Result(){ yuv4*
super(); "|hlDe<
} 8+ hhdy*b
` .$&T7
/** `
jyKCm.$#
* The constructor using fields &//2eL
* TA| s@T{
* @param page ?9Ma^C;}
* @param content E>"8/
*/ {"t5\U6cKM
public Result(Page page, List content){ \FXp*FbQ
this.page = page; ~?d>fR:X
this.content = content; ;Yv14{T!
} >uHb ^
{!r#f(?uT
/** _ ~[M+IO
* @return Returns the content. 1fR P1
*/ %4/xH9
publicList getContent(){ JRo;(wqZ
return content; Bq;1^gtpe
} x9D/s`!
Sz)b7:
/** jqtVpNwM
* @return Returns the page. _JA:.V^3gm
*/ !=y Q)l2
public Page getPage(){ @h9K
return page; d>/Tu_ y
} TL'0T,Jo
fM2^MUp[=1
/** wV>c" J
* @param content YXRjx.srf
* The content to set. WL:0R>0
*/ c 6q/X*
public void setContent(List content){ "koo` J
this.content = content; *6P'q4)
} -;/
Y
\%4|t,en
/** h$/JGm5uDb
* @param page H?{MRe
* The page to set. "k, K ~@}
*/ QF&6?e06p0
publicvoid setPage(Page page){ ]'UgZsJ
this.page = page; ~of,,&
} _#vGs:-x&
} ^)<