Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 o.j;dsZ
,cbP yg
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 :!aFfb["
&=s{ +0
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 %0"o(y+zt
(T`x-wTl
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 5Pv>`E2^
b\;QR?16R
。 BKJW\gS2
D{G#|&;
分页支持类: ,sJ{2,]~
n){\KIU/O
java代码: @o>2:D1G
3EzI~Zsx
cvc.-7IO
package com.javaeye.common.util; j[=f;&1
0eb`9yM
import java.util.List; Lqz}h-Ei
2>s:wABb /
publicclass PaginationSupport { Cu9,oU+N
67f#Z&r2k
publicfinalstaticint PAGESIZE = 30; HK
;C*;vC%
f5`exfdHE
privateint pageSize = PAGESIZE; KXR
B%r)~?6DM
privateList items; h{>8W0W*
N(F9vZOs
privateint totalCount; Le_?x
II[qWs>RG[
privateint[] indexes = newint[0]; R=PjLH&)
eaCEZHr$
privateint startIndex = 0; 33
N5> }
k.0$~juu
public PaginationSupport(List items, int ,!Ah+x
#mtlgK'
totalCount){ <v0 d8
setPageSize(PAGESIZE); Ee4oTU5Mb
setTotalCount(totalCount); |ss_<
setItems(items); 'm-s8]-W
setStartIndex(0); iiO4.@nT
} w'U;b
|%TH|?kB
public PaginationSupport(List items, int 5w{_WR6,
!_zmm$bR
totalCount, int startIndex){ "rkP@ja9n
setPageSize(PAGESIZE); 9g "?`_
setTotalCount(totalCount); M|76,2u
setItems(items); Riu0;U( \
setStartIndex(startIndex); @XB/9!
} 6kYn5:BhIi
?1 ?m4i
public PaginationSupport(List items, int wVw3YIN#
=y^N'1q
totalCount, int pageSize, int startIndex){ r=s2wjk
setPageSize(pageSize); Tpkm\_
setTotalCount(totalCount); -YRF^72+
setItems(items); P>jlFm
setStartIndex(startIndex); IDwneFO
} Fe`$mtPu .
6(X(f;MEl
publicList getItems(){ S,qsCnz
return items; r@k&1*&
} }&EPH}V2n
I?5#Q0,b
publicvoid setItems(List items){ #@lLx?U
this.items = items; M0n@?S
} LXfDXXF
L?<V KT
publicint getPageSize(){ )1&[uE#L
return pageSize; 1^Ci$ra
} _fa2ntuS=f
i>>_S&!9p
publicvoid setPageSize(int pageSize){ lYD-U8
this.pageSize = pageSize; "J7=3$CA
}
g$9Yfu
zTm&m#){3A
publicint getTotalCount(){ *|ubH?71%Y
return totalCount; ~b\bpu
} AfFFu\
E*j)gj9
publicvoid setTotalCount(int totalCount){ oTT/;~ I
if(totalCount > 0){ {N/(lB8
this.totalCount = totalCount; jQ(qaX&
int count = totalCount / 0P&rTtU6
1Ep!U#Del
pageSize; @6(4}&sEdm
if(totalCount % pageSize > 0) A0
x*feK?
count++; ?0Z?Z3)%w4
indexes = newint[count]; `a98+x?JF
for(int i = 0; i < count; i++){ d1vC-n
N
indexes = pageSize * 34&n{ xv
vRYfB{~
i; #4DEb<D
} <jY"+@rF
}else{ 2LEf"FH0~
this.totalCount = 0; `o)rAD^e
} ,J!G-?:@n
} q0SYV
cxp>4[gH
publicint[] getIndexes(){ dzKI?i)x
return indexes; 3g0[(;
} w0q.cj@nd
`XE8[XY
publicvoid setIndexes(int[] indexes){ :Fm;0R@/k
this.indexes = indexes; ~K&ko8
} H?m9HBDpn
GNgPf"}K
publicint getStartIndex(){ \U\ W Q
return startIndex; ncuqo'r
} DW\';"
d
*!) wt
publicvoid setStartIndex(int startIndex){ ^M0e 0
if(totalCount <= 0) dmgoVF_qR
this.startIndex = 0; iOYC1QFi?
elseif(startIndex >= totalCount) < HlS0J9
this.startIndex = indexes :D\M.A
N \1
EWi
[indexes.length - 1]; fzT|{vG8
elseif(startIndex < 0) S8(Y+jgk;a
this.startIndex = 0; 3WHj|ENW
else{ p%/Z
this.startIndex = indexes lyc
]E
9
AqM}@2#%%
[startIndex / pageSize]; dUegHBw_`R
} w~{NNK;"j
} V+G.TI
P
%{?EfULg
publicint getNextIndex(){ HRS^91aK
int nextIndex = getStartIndex() + Ro\ U T64
j>Ce06G
pageSize; plcz m 2
if(nextIndex >= totalCount) &Azfpv
return getStartIndex(); o/??w:'
else lR3`4bHA
return nextIndex; F6^Xi"R[
} X`
r~cc
uJhB>/Og
publicint getPreviousIndex(){ =]i[gs)B
int previousIndex = getStartIndex() - V9
Z
82d~>i%T
pageSize; S<fSoU+RJ
if(previousIndex < 0) c~ x
return0; .{r 0Szm.
else !(2rU @.
return previousIndex; r Z)?uqa
} TC[(mf:8
K{DsGf,
} mcO/V-\5'
s9^r[l@W0U
pe%$(%@v
\MhSIlM#
抽象业务类 5jMI33D
java代码: qrdA4S
[9N>*dKB
F{,<6/ayRz
/** }[2
* Created on 2005-7-12 B L^?1x
*/ $?`-} wY
package com.javaeye.common.business; *BdKQ/Dk
' 5tk0A
import java.io.Serializable; _`|te|ccF
import java.util.List; LeP;HP|
Q6qIx=c4
import org.hibernate.Criteria; 9pF@#A9p
import org.hibernate.HibernateException; GQ-fEIi{
import org.hibernate.Session; `_;sT8
import org.hibernate.criterion.DetachedCriteria; ^\"@r%|
import org.hibernate.criterion.Projections; 1 >}x9D
import NAg9EaWja{
n VNz5B
org.springframework.orm.hibernate3.HibernateCallback; (Mzv"F N]
import t,P_&0X
.R";2f3
org.springframework.orm.hibernate3.support.HibernateDaoS
}.DE521u
Qvc$D{z
upport; !{S& "
AT{rg/oSf
import com.javaeye.common.util.PaginationSupport; Sj(5xa[
\5
S^~(iL
public abstract class AbstractManager extends azBYh*s=5{
L|hoA9/]
HibernateDaoSupport { Acix`-<
C
9{8!fYp
privateboolean cacheQueries = false; a*kvU "]
3bU(ea^e$
privateString queryCacheRegion; XK+"
x!
dilom#2l
publicvoid setCacheQueries(boolean =Ts5\1sc>
ko-,l6E
cacheQueries){ d94Le/E
this.cacheQueries = cacheQueries; [aS<u`/g|
} >))f;$D=
:HiAjaA1pg
publicvoid setQueryCacheRegion(String R\T1R"1
T9'd?nw9
queryCacheRegion){ '$q=r x
this.queryCacheRegion = >}7Ml
je#OV,uHM
queryCacheRegion; m%s&$
} T1*%]6&V|
Q1[3C(
publicvoid save(finalObject entity){ 0d|DIT#>?
getHibernateTemplate().save(entity); CM`B0[B
} S*3*Q l*
*}h#'+
publicvoid persist(finalObject entity){ 1Qk]?R/DN
getHibernateTemplate().save(entity); I6e[K(7NY
} %
|^V)
)q|a Sd
publicvoid update(finalObject entity){ `EdZ
getHibernateTemplate().update(entity); nRHxbE}::
} <y2HzBC
Fm#`}K_
publicvoid delete(finalObject entity){ YwizA}a#
getHibernateTemplate().delete(entity); dTrz7ayH
} E'
_6v
IzI2w6a
publicObject load(finalClass entity, MUW&m2
qokCVI-\
finalSerializable id){ UFzC8
return getHibernateTemplate().load IQ\5!e
or
qL0i
(entity, id); e.VQ!)>
} >[0t@Tu,D
5HC5
publicObject get(finalClass entity, s1>d)2lX
K41Gn
finalSerializable id){ H8!)zZ
return getHibernateTemplate().get OPuty/^!Gw
.LI(2lP
(entity, id); I} .9
} !nDiAjj
w| eVl{~p
publicList findAll(finalClass entity){ 8pXqgIbmb
return getHibernateTemplate().find("from cH:9@> '$a
XGb*LY+Db6
" + entity.getName()); @j<Q2z^
} !~Ptnr`;
AL{iQxQ6
publicList findByNamedQuery(finalString z7_h$v
3}2;*:p4Y
namedQuery){ S|
|OSxZ
return getHibernateTemplate eb>jT:
d6e$'w@(\T
().findByNamedQuery(namedQuery); $1y8X K7r
} n{I1ZlEeh
RxE.t[
publicList findByNamedQuery(finalString query, :/R>0 n,
l T#WM]
finalObject parameter){ l:+$K s
return getHibernateTemplate Hxx]q+DAS
* hmoi
().findByNamedQuery(query, parameter); _BoYyJQH
} muMd9\p
w0X})&,{`m
publicList findByNamedQuery(finalString query, Vg(FF"
4rLc]
>
finalObject[] parameters){ ?c<uN~fC=
return getHibernateTemplate T3NH8nH9"z
9aBz%* xo
().findByNamedQuery(query, parameters); 0Ibe~!EiQJ
} Q7]bUPDO
z.Vf,<H
publicList find(finalString query){ ~ycWcZi>
return getHibernateTemplate().find Vn65:" O
E9\u^"GVO
(query); \}J"`J\Q
} ZypK''&oc
~^PNMZk
publicList find(finalString query, finalObject NiYT%K%
'p[*2J"K4
parameter){ d;nk>6<|
return getHibernateTemplate().find @KRia{
^Y%<$IFG
(query, parameter); N;a' `l
} z31g"
1)3'Y2N*
public PaginationSupport findPageByCriteria ,Jx.Kj.,
EE*|#
(final DetachedCriteria detachedCriteria){ p=V1M-
return findPageByCriteria D&x.io
}USOWsLSt
(detachedCriteria, PaginationSupport.PAGESIZE, 0); NHcA6y$Cz
} W$<Y**y9m
yg6o#;
public PaginationSupport findPageByCriteria .Fx3WryF
N85ZbmU~
(final DetachedCriteria detachedCriteria, finalint 2%|n}V[
p,tkVedR
startIndex){ k;K-6<^h
return findPageByCriteria ] &SmeTe
BSL+Gjj~}
(detachedCriteria, PaginationSupport.PAGESIZE, CM6! 1 7
IBUFXzl
startIndex); \t%iUZ$
} P$]K
#.vp\W
public PaginationSupport findPageByCriteria I%b5a`7
w}s5=>QG%
(final DetachedCriteria detachedCriteria, finalint ^M\X/uq$E
]E)D})r`#
pageSize, ~~O4!|t
finalint startIndex){ :9e4(7~ona
return(PaginationSupport) mM~&mAa+Z
; K,5qs
getHibernateTemplate().execute(new HibernateCallback(){ #M<YNuE#"
publicObject doInHibernate i/Nc)kKL
49HP2E
(Session session)throws HibernateException { C^c<s
Criteria criteria = \qTp#sF
Hy -)yR
detachedCriteria.getExecutableCriteria(session); B%`|W@v
int totalCount = H?FiZy*[Y
)L7[;(gQ
((Integer) criteria.setProjection(Projections.rowCount ^=a:{["@!
;$8ptB .
()).uniqueResult()).intValue(); Sy]W4%
criteria.setProjection fqBz"l>5A
Y]^*mc0fE
(null); ?NvE9+n
List items = -8vGvI>
'n^?DPvD
criteria.setFirstResult(startIndex).setMaxResults s
Ytn'&$\
@4KKm@(p85
(pageSize).list(); zo("v*d*q
PaginationSupport ps = 9I`0`o"A
"kC6G%
new PaginationSupport(items, totalCount, pageSize, }gFa9M<
n*i&o;5
startIndex); {U@"]{3Qx
return ps; epG]$T![
} ,7 m33Pv*
}, true); Q&lb]U+\u
} _zzT[}
.t9`e=%
public List findAllByCriteria(final %%I:L~c
Zop/ MeI
DetachedCriteria detachedCriteria){ e@]m@
return(List) getHibernateTemplate V|F/ynJfA
6
8fnh'I!
().execute(new HibernateCallback(){ X}5"ZLa7l
publicObject doInHibernate F_i"v5#
g/WDAO?d
(Session session)throws HibernateException { f="Zpl W
Criteria criteria = MmU`i ,z
q2OF-.rE
detachedCriteria.getExecutableCriteria(session); /;:4$2R(;
return criteria.list(); B5h)F> &G
} ^ UhqV"[7k
}, true);
m5a'Vs
} R4'>5.M
8r:T&)v
public int getCountByCriteria(final b|G~0[g
DZLEx{cm
DetachedCriteria detachedCriteria){ 1|s`z
Integer count = (Integer) N)a5~<fBG
;CoD5F!
getHibernateTemplate().execute(new HibernateCallback(){ &U CtyCz
publicObject doInHibernate A>315!d"
^|vP").aQm
(Session session)throws HibernateException { :Ig9n:
Criteria criteria = b$pCp`/MT
*b!.9p K
detachedCriteria.getExecutableCriteria(session); k_Sm ep
return k2 _y84;D
U#sv.r/L}3
criteria.setProjection(Projections.rowCount EZVgTySd
^^24a_+2
()).uniqueResult(); ^vv1cft
} T-lP=KF=
}, true); wlh%{l
return count.intValue(); +z#+}'mT%
} hOV5WO\
} 1W-kZ(e
w@YPG{"j
F x$W3FIO]
u[4h|*'"|
|oX9SU l
/,j'Vr\"
用户在web层构造查询条件detachedCriteria,和可选的 D vN0h(?
^JY:$)4["
startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;*U&lT
$]W*;MTI}
PaginationSupport的实例ps。 ZEpu5`
%,@e- &>
ps.getItems()得到已分页好的结果集 usu{1&g
ps.getIndexes()得到分页索引的数组 3RD+;^}q3
ps.getTotalCount()得到总结果数 Q84XmXm|
ps.getStartIndex()当前分页索引 hOs~/bM
ps.getNextIndex()下一页索引 a^X% (@Sg
ps.getPreviousIndex()上一页索引 ADP3Nic
\q^dhY>)
BvH I}=
31M'71s
AT2D+Hi=E
X3XTB*
9\E];~"iP
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 C nD3%%
!>+m46A
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 &sXk!!85:
I8IH\5k
一下代码重构了。 8Bxb~*
+K2HMf'
我把原本我的做法也提供出来供大家讨论吧: =NPo<^Lae
b"w2 2%
首先,为了实现分页查询,我封装了一个Page类: BHNJH
java代码: b`cH.v
|h((SreO
1pN8,[hyR7
/*Created on 2005-4-14*/ a+9_sUq
package org.flyware.util.page; EIg:@o&Jj
/"R{1
/** Z^K WYe'w
* @author Joa 9/R=_y-
* |+<o(Q(
*/ em ]0^otM
publicclass Page { S6_dmTV*
jT-tsQ .,
/** imply if the page has previous page */ wc}4:~
privateboolean hasPrePage; 2e({%P@2?
_gCi@uXS3
/** imply if the page has next page */ 3Ea/)EB]
privateboolean hasNextPage; _Pl5?5eZj
lXnv(3j3*s
/** the number of every page */ A2`Xh#o
privateint everyPage; CzmB76zy.
_M- PF$
/** the total page number */ yoBR'$-=
privateint totalPage; id1gK(F8H
bHzH0v]:
/** the number of current page */ Cg^1(dBd[9
privateint currentPage; #/hXcF
9tCF m.m
/** the begin index of the records by the current &Z7 NF|
M-C>I;a
query */ ,sp( (SF]1
privateint beginIndex; okbW. ~
"z{rC}
!q^2| %
/** The default constructor */ (Lkcx06e
public Page(){ ^4a|gc
^'hh?mL
} OkQtM
nq
C4eQ.ep
/** construct the page by everyPage [-3x *?Ju
* @param everyPage Tpp?(lT7r
* */ WiF6*]oI
public Page(int everyPage){ '77Gg
this.everyPage = everyPage; H+VjY MvK
} aByd,uSe)_
]_:j+6i
/** The whole constructor */ <+p{U(
public Page(boolean hasPrePage, boolean hasNextPage, \7*"M y*
jd}-&DN
,4S6F HK
int everyPage, int totalPage, "jP{m;p
int currentPage, int beginIndex){ 2U'Vq
this.hasPrePage = hasPrePage; A04E <nr
this.hasNextPage = hasNextPage; Z
WhV"]w&
this.everyPage = everyPage; p4wx&VLi
this.totalPage = totalPage; V7,;N@FL
this.currentPage = currentPage; c+G%o8
this.beginIndex = beginIndex; K,f-
w2!
} xn2f!\%p
4+B
OS ~
/** m+pFU?<|
* @return <U2Un 0T
* Returns the beginIndex. bA(-7l?
*/ ~x g#6%<=
publicint getBeginIndex(){ PsyXt5Dk
return beginIndex; dC8,
} ]+@I]\S4
!2]'S=Y
/** n~?n+\.&a
* @param beginIndex
sf'+;
* The beginIndex to set. Tu}?Q.pKo
*/ /fC8jdp&
publicvoid setBeginIndex(int beginIndex){ y"Jma`Vjq
this.beginIndex = beginIndex; p!H'JNG
} ?9:~d#p
{4HcecT
/** E6s)J -a
* @return ^,6c9Dxy
* Returns the currentPage. "\l#q$1h
*/ vALH!Kh
publicint getCurrentPage(){ Yjh02wo
return currentPage; d\j[O9W>
} b'
fcWp0
6w4}4i
/** :a'[4w
* @param currentPage {9<c*0l
* The currentPage to set. R}HNi(%"
*/ roHJ$~q?
publicvoid setCurrentPage(int currentPage){ V8"m_
this.currentPage = currentPage; !6l}s$1i|
} Z:Y_{YAD
y}GFtRNG
/** D>
E N:_v
* @return I9O%/^5^[w
* Returns the everyPage. zL/rV<
*/ y.Y;<UGu
publicint getEveryPage(){ G)3Q|Vc
return everyPage; 9UE)4*5
} O("13cU
tDn:B$*}W,
/** *8I &|)x
* @param everyPage Vl%UT@D|
* The everyPage to set. *`~]XM@H
*/ Y [%<s/
publicvoid setEveryPage(int everyPage){ pRGag~h|E
this.everyPage = everyPage; JbLHW26pl
} /uJ(W
Rh#QPYPq
/** /#g
P#Z%
* @return D&!c7_ ^
* Returns the hasNextPage. 0Q!/A5z
*/ kB-]SD#
publicboolean getHasNextPage(){ J*;= f8
return hasNextPage; >Q[3t79^
} 1Ms_2
T*jQzcm~?
/** i 2l/y,UX
* @param hasNextPage Ff&kK5}q
* The hasNextPage to set. tx ,q=.(
*/ ^50\c$
publicvoid setHasNextPage(boolean hasNextPage){ G|.6%-
this.hasNextPage = hasNextPage; 3#N`n |UgC
} N<^)tR8+
^5rB/y,
/** ,C0D|q4/!.
* @return y_LFkZ
* Returns the hasPrePage. @Io@1[k j
*/ )LTX.Kg
publicboolean getHasPrePage(){ B,U|V
return hasPrePage; @K1'Q!S*
} tP4z#0r2
BKKW3PT
/** {JQCfs
* @param hasPrePage r7-H`%.
* The hasPrePage to set. 2B b,ZC*
*/ ~Z' /b|x<3
publicvoid setHasPrePage(boolean hasPrePage){ KW(^-:wmr
this.hasPrePage = hasPrePage; jM:|%o
} jwmPy)X|s\
;e6L@)dp9
/** /Xl(>^|&
* @return Returns the totalPage. xM=?ES
* 4Q:r83#
*/ Y 2[ik<
publicint getTotalPage(){ lf#5X)V
return totalPage; )zkr[;j~`
} @*BVS'\
lJdrrR)wg
/** Qt>Bvu Q
* @param totalPage Zs2;VW4RW
* The totalPage to set. |_ OoD9,M
*/ cCs@[D#O1
publicvoid setTotalPage(int totalPage){ UJ><B"
this.totalPage = totalPage; kgd
dq
} X@za4d
:9f 9Z7M
} .rQcg.8/B
EQ]>^VE2B
M[cAfu
E:Ul_m8
dF7`V J2
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 ^%O$7*
B.L _EIw
个PageUtil,负责对Page对象进行构造: o1thGttVDg
java代码: m -0}Pe9L
.E;}.X
~( :$c3\
/*Created on 2005-4-14*/ -Gjz+cRns
package org.flyware.util.page; i
^,
$/
h{ZK;(u$
import org.apache.commons.logging.Log; 8S5Q{[ !
import org.apache.commons.logging.LogFactory; vAjog])9s
ra8AUj~RX
/** =3PZGdWD
* @author Joa }\1V%c
* xeKm} MN]S
*/ eQ,VK`7X
publicclass PageUtil { ),H1z`c&I
` 5n^DP*X
privatestaticfinal Log logger = LogFactory.getLog L s+zJ1
( dh9aR_a
(PageUtil.class); Zzmo7kFx3
GC|V>| tz#
/** n g9_c
* Use the origin page to create a new page !wC(
]Y
* @param page bK{ VjXF
* @param totalRecords eN`G2eE
* @return kx;7/fH
*/ {asq[;]
publicstatic Page createPage(Page page, int aGAr24]y
_|{Z850AS
totalRecords){ 5Q: %f
return createPage(page.getEveryPage(), g?*D)WU
A)&CI6(
page.getCurrentPage(), totalRecords); ])q,mH
} *;Cpz[N
?!.J0q
/** GNSh`Tm =#
* the basic page utils not including exception 1$^r@rP
#99 =wn
handler wk'&n^_br
* @param everyPage eU.C<Tv:8
* @param currentPage 7Sh1QDYZ
* @param totalRecords n/e ,jw
* @return page y
qK*E*
*/ oE2VJKs<B
publicstatic Page createPage(int everyPage, int G<]@nP{P
(Ffa{Tt!
currentPage, int totalRecords){ aj=-^iGG
everyPage = getEveryPage(everyPage); -$49l
currentPage = getCurrentPage(currentPage); BB_(!omq[
int beginIndex = getBeginIndex(everyPage, (*,R21<%
^ >
?C
currentPage); SLp nVD:'1
int totalPage = getTotalPage(everyPage, DyA1zwp}
Nq|y\3]
totalRecords); L\!Oj5
boolean hasNextPage = hasNextPage(currentPage, %a:T9v
keStK8
totalPage); Z,"YMUl'
boolean hasPrePage = hasPrePage(currentPage); -B(p8 YH
O[z6W.
returnnew Page(hasPrePage, hasNextPage, n xR\tBv
everyPage, totalPage, t~BWN
currentPage, m=Mk@xfQ#
&}K%F)S
beginIndex); V#R; -C
} PWquu`
P#
U|
privatestaticint getEveryPage(int everyPage){ \Co
Z+
return everyPage == 0 ? 10 : everyPage; Lr(JnS
} 7!)VOD8Z
.F[5{XV
privatestaticint getCurrentPage(int currentPage){ edZBQmx+#
return currentPage == 0 ? 1 : currentPage; 4ElS_u^cP7
} &JD^\+7U:
ed`7GZB
privatestaticint getBeginIndex(int everyPage, int *P&lAyt6
ePxAZg$ `>
currentPage){ .9Dncsnf,`
return(currentPage - 1) * everyPage; N P5K1:
} O7yj<
/b/ 6*&
privatestaticint getTotalPage(int everyPage, int <7zz"R
VuN#j<H
totalRecords){ _a_T`fE&de
int totalPage = 0; 5H|7DVG
*i!t&s
if(totalRecords % everyPage == 0) 0%,?z`UY
totalPage = totalRecords / everyPage; (E~6fb"c
else "9N;&^I
totalPage = totalRecords / everyPage + 1 ; n</Rd=
8Z)wot
return totalPage; Fq%NY8KNE
} uD[T l
6\.LG4@LO
privatestaticboolean hasPrePage(int currentPage){ 2Uu!_n}tNF
return currentPage == 1 ? false : true; &qIdT;^=I
} ic l]H
YkFERIa076
privatestaticboolean hasNextPage(int currentPage, aSgKh
Uv~|Xj4.
int totalPage){ bQ&%6'ck
return currentPage == totalPage || totalPage == K}GRU)
x|()f3{.
0 ? false : true; F
IB)cpo
} @xBO[v
fvV"H{V,
\MPbG$ ^
} Vl>KeZ+
4]-7S l,
2uV5hSHYe
e@/' o/
CC3M7|eO3
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。 e<FMeg7n
![J_6f}!
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 d>Nh<PqH6
A>HCX 4i
做法如下: m`]d`%Ex
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 N[v=;&
mgM"u94-]
的信息,和一个结果集List: ?IoA;GBg
java代码: |WfL'_?$
~[~#PO
yNU}1_oK
/*Created on 2005-6-13*/ _+~&t9A!
package com.adt.bo; Xs'qwL~{`
-(ST
import java.util.List; */K]sQZa
pF8+<
T3y
import org.flyware.util.page.Page; z<0/#OP'
(hIo0.
/** -})zRL0!'
* @author Joa
C?'s
*/ iun_z$I<+Z
publicclass Result { !$!%era`
KGI<G
private Page page; ]D=fvvST
>J_P[v
private List content; |YfJ#Agm+
I:YgKs)[
/** D,(:))DmR
* The default constructor sB^ejH
*/ %=\*OIhl
public Result(){ Nw-U*y
super(); Kxz|0l
} {LCKt/Z>P
r}:U'zlC{
/** UdA,.C0
* The constructor using fields .WuSW[g
* !C^>tmqS
* @param page cR*~JwC:
* @param content x-4d VKE*z
*/ ]#G1
]U
public Result(Page page, List content){ 2t45/:,
this.page = page; xe3Jxo!U
this.content = content; H\9ePo\b~
} NmF8BmIj
GxC\Nj#
/** lQm7`+
* @return Returns the content. &n0Ag]$P
*/ J Rj{Q 1J
publicList getContent(){ \b$Y_
return content; Gm0}KU
} p1mAoVxR
h|lH`m^
/** YNKvR
* @return Returns the page. ,Ik~E&Ku2'
*/ pE X Q
public Page getPage(){ u),.q7(m
return page; 6VJS
l%X
} uf:'"7V7
'- #QK'p
/** HNlW.y"
* @param content NGO?K?
* The content to set. 'SrDc'?
*/ zvdIwV&oT
public void setContent(List content){ t"e %'dFv
this.content = content; j7NOYm5N
} OIjG`~Rx
ld 1[Usaq
/** C#3&,G W
* @param page vmo!
* The page to set. ej=}OH4
*/ 5D
XBTpCVM
publicvoid setPage(Page page){ roe_H>
this.page = page; sN5Mm8~
} h,b_8g{!
} SxcE@WM
m#RMd,'X
TD4
n%k.
`Ao"fRv#
9F~5Ht
2. 编写业务逻辑接口,并实现它(UserManager, cFuQ>xR1
eiRVw5g
UserManagerImpl) ;<xPzf
java代码: 6wXy;!2
#c'}_s2F[
G(t&(t`[
/*Created on 2005-7-15*/ ]"j%:fr
package com.adt.service; Ln/*lLIOb
HW"5MZ8E
import net.sf.hibernate.HibernateException; w7vQ6jkH
Qp2~ `hD
import org.flyware.util.page.Page; Hd
gABIuX
wWq-zGH|&