Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 @Sub.z&T{
*~ 4uF
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ` ]WU=Ss
{_3ZKD(\
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 4,FkA_k
N3vk<sr@
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 h'UWf"d
FlVGi3
。 lhQ*;dMj%"
/RmLV
分页支持类: BEPDyy
VbBZ\`b
java代码: 5/:Zj,41{
E_WiQ?p
@Z@yI2#e
package com.javaeye.common.util; !bH-(K{S6
3dadeu^{A
import java.util.List; Ow//#:
~DqNA%Mb
publicclass PaginationSupport { 3zWY%(8t4?
X,O&X
publicfinalstaticint PAGESIZE = 30; j(nPWEyJM
c)@M7UK[
privateint pageSize = PAGESIZE; ?\$77k
%PlPXoG=
privateList items; p4{?Rhb6
h]@Xucc
privateint totalCount; ( }JX ]-
c~RElL
privateint[] indexes = newint[0]; woR((K] #G
v~ uwQ&AH
privateint startIndex = 0; IeN!nK-
,Hys9I
public PaginationSupport(List items, int +/Y)s5@<
uT;Qo{G^
totalCount){ ?0'bf y]
setPageSize(PAGESIZE); Zpu>T2Tp
setTotalCount(totalCount); r)X?H
setItems(items); f_raICO{R
setStartIndex(0); 2vj)3%:7#E
} ]BAF
i7 p#%2
public PaginationSupport(List items, int 9SAyU%mS:
[&+wW
totalCount, int startIndex){ qY14LdC}~
setPageSize(PAGESIZE); -pqShDar|
setTotalCount(totalCount); n4Q!lJ
setItems(items); Ap}:^k5{
setStartIndex(startIndex); i"w$D{N
} ,dh*GJ{5
aK1|b=gVj
public PaginationSupport(List items, int @*%.V.
I[[rVts
totalCount, int pageSize, int startIndex){ x]a>Q),
setPageSize(pageSize); Z71"d"
setTotalCount(totalCount); bd)A6a\h
setItems(items); _v2FXm
setStartIndex(startIndex); /5yWvra
} cp.)K!$
Pi+,y
publicList getItems(){ JN3Oe5yB2@
return items; [IV8
} 2]>s@?[
n$b/@hp$z
publicvoid setItems(List items){ bcj7.rh]'h
this.items = items; 7Bmt^J5i&t
} pazFVzT
uOW9FAW
publicint getPageSize(){ vn,L),"=
return pageSize; %? RX}37K
} {W0]0_mI(
I S!B$
publicvoid setPageSize(int pageSize){ :_H$*Q=1
this.pageSize = pageSize; TR:D
} \:"s*-
>_&+gn${
publicint getTotalCount(){ -?e~S\JH
return totalCount; U<#i\4W
} 0V`/oaW;
KUuwScb\
publicvoid setTotalCount(int totalCount){ JLg_oK6
if(totalCount > 0){ "$Rl9(}
this.totalCount = totalCount; //6m2a
int count = totalCount / 0 ]NsT0M
5IMh$!/uc
pageSize; i>e7 5`9
if(totalCount % pageSize > 0) A?6b)B/e?
count++; XPX{c|]>.
indexes = newint[count]; Ui1K66{
for(int i = 0; i < count; i++){ D;:lw]
indexes = pageSize * Vwv O@G7A
m'429E]\S
i; [ ra[~
} 9prG@
}else{ )EcF[aO
this.totalCount = 0; %7V?7BE
} "pHQ
} I98wMV8
;l?>+m@H
publicint[] getIndexes(){ v8wN2[fC
return indexes; flmcY7ZV
} Y
@K9Hl
Vxk0oIk`
publicvoid setIndexes(int[] indexes){ w|$;$a7)
this.indexes = indexes; l sUQ7%f
} %0"o(y+zt
A)VOv`U@2
publicint getStartIndex(){ Zl* HT%-5
return startIndex; (r7~ccy4
} $v>- @
Q0M8}
publicvoid setStartIndex(int startIndex){ sb8SG_ c.
if(totalCount <= 0) 57r\s8
this.startIndex = 0; qnT:x{o
elseif(startIndex >= totalCount) *9*I:Uh57
this.startIndex = indexes ,cj34W`FWq
h3JIiwv0!
[indexes.length - 1]; EcP"GO5
elseif(startIndex < 0) >Axe7<l
this.startIndex = 0; \WZ00Y,*
else{ irrQ$N}
this.startIndex = indexes 6i&WF<%D
7]
~'8
[startIndex / pageSize]; 0WYVt"|;}c
} !m^WtF
} N!btj,vx
~IlgcCF
publicint getNextIndex(){ @n})oAC,
int nextIndex = getStartIndex() + AMtFOXx%I
7(wY4T
pageSize; |n* I}w^
if(nextIndex >= totalCount) sd#a_
return getStartIndex(); R#Ss_y
else Ee4oTU5Mb
return nextIndex; q}+9$v
} v`nodI
(8{h I
publicint getPreviousIndex(){ ;:'A{&0N
int previousIndex = getStartIndex() - Is%-r.i
!_zmm$bR
pageSize; +}*]9nG
if(previousIndex < 0) ?;}2Z)
return0; x+^iEj`gk
else D(L%fK` +
return previousIndex; &{l?j>|TM
} n?:s/6tP
N<O^%!bu R
} ?l
bK;Kv
?2DYz"/')
OSsdB%bIu`
opdi5e)jK
抽象业务类 'rU5VrK
java代码: Fe`$mtPu .
7pr@aA"vgj
e|xRK?aVBu
/** H?^Poe(=(
* Created on 2005-7-12 MJDFm,
*/ \>M3E
package com.javaeye.common.business; # l}Y1^PDd
)*$'e<?`
import java.io.Serializable; o'r?^ *W
import java.util.List; D0tI
*7DQ#bD
import org.hibernate.Criteria; IQY\L@"
import org.hibernate.HibernateException; aElEV
e3
import org.hibernate.Session; mI?AI7DqK
import org.hibernate.criterion.DetachedCriteria; yv]/A<gP+
import org.hibernate.criterion.Projections; ,in`JM<o
import #t
po@pJsE
rS8/_'
org.springframework.orm.hibernate3.HibernateCallback; M)(
5S1ndq
import lP\7=9rh^x
jt=mK,%
org.springframework.orm.hibernate3.support.HibernateDaoS $oe:km1-D
@6(4}&sEdm
upport; Pr<.ld\
K'Bq@6@C g
import com.javaeye.common.util.PaginationSupport; &mp=j GR
VuPa'2
public abstract class AbstractManager extends kk
)9!7
~UEft
HibernateDaoSupport { &0+;E-_
GUJx?V/[
privateboolean cacheQueries = false; m fg{% .1
\Om.pOz
privateString queryCacheRegion; fiES6VL
cxp>4[gH
publicvoid setCacheQueries(boolean o{37}if
>01&3-r
cacheQueries){ q`{crY30
this.cacheQueries = cacheQueries; Xg_M{t
} M._9/
*C U
)C|[j@MD
publicvoid setQueryCacheRegion(String u|BD=4*
xf_NHKZ)
queryCacheRegion){ ,Hlbl}.ls
this.queryCacheRegion = a;r,*zZ="
Lf4c[[@%gd
queryCacheRegion; }4Ef31X8q
} q@1b{q#C5
*I:^g
publicvoid save(finalObject entity){ 'avzESe~'
getHibernateTemplate().save(entity); w@ALl#z;}
} 2? 9*V19yu
e`27 ?
publicvoid persist(finalObject entity){ "j#;MOK
getHibernateTemplate().save(entity); nd_+g2x'
} G6]W'Kk
;~CAHn|Fe
publicvoid update(finalObject entity){ 5 Sm9m*/
getHibernateTemplate().update(entity); 2uujA*
^
} l.[S.@\ =.
k]K][[s`
publicvoid delete(finalObject entity){ 2_k2t
?
getHibernateTemplate().delete(entity); BC.~wNz6
} X`
r~cc
b9`vYnLk
publicObject load(finalClass entity, j
N":9+F
)nE=H,U?y
finalSerializable id){ pbc<326X"
return getHibernateTemplate().load _-mSK/Z
.{r 0Szm.
(entity, id); }h{8i_R
} )zn`qaHK@e
%+gK5aVab
publicObject get(finalClass entity, Cb:}AQ =
dA4DW
finalSerializable id){ pe%$(%@v
return getHibernateTemplate().get `_"F7Czn
re}_+svU
(entity, id); P?WS=w*O0
} GS_+KR\
}[2
publicList findAll(finalClass entity){ P qUjBP\
return getHibernateTemplate().find("from L F<{/c9,
u_31Db<
" + entity.getName()); K9G1>*
}
yn`P:[v
=Pj+^+UM
publicList findByNamedQuery(finalString o,(]w kF
t_ju[xL5B
namedQuery){ kz30! L
return getHibernateTemplate L<dJWxf?D
}Zuk}Og9+
().findByNamedQuery(namedQuery); cpLlkR O
} 2?c##Izn
@}{lp'8FYi
publicList findByNamedQuery(finalString query, p<[gzmU9\b
rm}%C(C{J
finalObject parameter){ h;C/} s
return getHibernateTemplate AT{rg/oSf
a%g |E'\Jw
().findByNamedQuery(query, parameter); ~6nY5
} THN//}d
m.6O%jD
publicList findByNamedQuery(finalString query, .m gm1zz
a*kvU "]
finalObject[] parameters){ 6<hE]B)
return getHibernateTemplate R"2wop
r `;_ #&b
().findByNamedQuery(query, parameters); 3u,C I!
} {wL30D^
.D8|_B
publicList find(finalString query){ >))f;$D=
return getHibernateTemplate().find |d)*,O4s
$S6%a9m
(query); chC= $(5t
} -s6k't
kfW"vI+d
publicList find(finalString query, finalObject RW4,j&)
d8C44q+ds
parameter){ l^k/Y
]
return getHibernateTemplate().find G^%FP!'D?
^0tO2$
(query, parameter); =bHS@h8N<
} P]^BE;7T
[:BD9V
public PaginationSupport findPageByCriteria uB1>.Pvxb
ks|c'XQb
(final DetachedCriteria detachedCriteria){ (ebC80M
return findPageByCriteria k}&7!G@T
Q8Fqf
;4
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 8\VP)<<
} YwizA}a#
n@te.,?A"
public PaginationSupport findPageByCriteria xf4CM,Z7(
;.U<Lr^9#
(final DetachedCriteria detachedCriteria, finalint Y
a/+|mv
/UG]hJ-wn
startIndex){ E=#
O|[=
return findPageByCriteria : *8t,f~s^
XVfw0-O
(detachedCriteria, PaginationSupport.PAGESIZE, >[0t@Tu,D
evvv&$&
startIndex); $)#?4v<
} rbl7-xhC7
O|AY2QH\
public PaginationSupport findPageByCriteria q|ZzGEj:OV
N;` jz(r
(final DetachedCriteria detachedCriteria, finalint cH:9@> '$a
M(U<H;Csk
pageSize, 85:KlBe%+
finalint startIndex){ D k<NlH zp
return(PaginationSupport) E_D0Nm%n
zQ#2BOx1
getHibernateTemplate().execute(new HibernateCallback(){ _$KEE|9
publicObject doInHibernate ER,!`C]
4TRF -f
(Session session)throws HibernateException { =p2: qSV
Criteria criteria = *cP(3n3]R
NjbIt=y
detachedCriteria.getExecutableCriteria(session); h?Lp9VF
int totalCount = l:+$K s
8?hZ5QvA(j
((Integer) criteria.setProjection(Projections.rowCount \SN>Yy
8ly6CP+^B
()).uniqueResult()).intValue();
i ?%_Pu
criteria.setProjection ~"VM_Lz]5
9qkJ<
(null); zF@[S
List items = (#BOcx5J]
&NX7
criteria.setFirstResult(startIndex).setMaxResults wGw<z[:f
K;ocs?rk/
(pageSize).list(); M5:j)oW
PaginationSupport ps = T"3:dkQw
3BSZz%va
new PaginationSupport(items, totalCount, pageSize, v7/k0D .
y@(EGfI
startIndex); ;`h$xB(
return ps; seVT|z
} \dbaY: (
}, true); cTQ._|M
} XAN.Plk
~ike&k{
public List findAllByCriteria(final V4&a+MJ@
hka%!W5
DetachedCriteria detachedCriteria){ L}7 TM:%
return(List) getHibernateTemplate >sZ_I?YDs
{v"Y!/
[z
().execute(new HibernateCallback(){ {55f{5y3
c
publicObject doInHibernate NHcA6y$Cz
XQ2YUe]DJ
(Session session)throws HibernateException { 22*~CIh~x
Criteria criteria = &dPI<HlM
CzIs_/
detachedCriteria.getExecutableCriteria(session); DyCkz"1S
return criteria.list(); \E'z+0
} Jpc% i8
}, true); BSL+Gjj~}
} |h\A5_0_
RXo 6y(^
public int getCountByCriteria(final =?_:h`}
<\$?.tTZ{
DetachedCriteria detachedCriteria){ 2D a0*xn{
Integer count = (Integer) 2.^CIJc
<g&.U W4
getHibernateTemplate().execute(new HibernateCallback(){ fCZ"0P3(
publicObject doInHibernate lbGPy'h<rt
A]1dR\p
(Session session)throws HibernateException { Dbb=d8utE
Criteria criteria = | )br-?2
$inKI
detachedCriteria.getExecutableCriteria(session); 49HP2E
return 7H|0.
0+[3>N y0
criteria.setProjection(Projections.rowCount =A~5?J=
I_e7rE0`
()).uniqueResult(); a^\F9^j
} O.Y|},F
}, true);
^6b5}{>
return count.intValue(); h6bvUI+|h
} S(^YTb7
} .l|29{J
zqURnsJ
5s;@ ;V
B.KK@
|`pBI0Sjo
_
nz^+
用户在web层构造查询条件detachedCriteria,和可选的 `gF`Sgz
DC8\v+K
startIndex,调用业务bean的相应findByCriteria方法,返回一个 yE.st9m
/D yig
PaginationSupport的实例ps。 K9Onjs%U
`z.sWF|f!O
ps.getItems()得到已分页好的结果集 -m[ tYp,q
ps.getIndexes()得到分页索引的数组 $at\aJ
ps.getTotalCount()得到总结果数 2Dt^W.!
ps.getStartIndex()当前分页索引 Ui-Y`
ps.getNextIndex()下一页索引 t=My=pG
ps.getPreviousIndex()上一页索引 4F6I7lu
K>5bb
U#- 5",X|
mM2I
u~VXe
6xY6EC
he@Y1CY
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 eu8a<
MxUQ F?@6
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做
m5a'Vs
,_/\pX0
一下代码重构了。 4E}Q<?UYSt
]&B/rSC
我把原本我的做法也提供出来供大家讨论吧: XR p60i6f
@HnahD
首先,为了实现分页查询,我封装了一个Page类: Hwtoa,
java代码: H6>t to
S6C DK:
"pcr-?L
/*Created on 2005-4-14*/ :cIPX%S
package org.flyware.util.page; ;Xqi;EA
Sn
7h$
/** uZ@qlq8
* @author Joa 69Z`mR
* ?B)e8i<[f
*/ LaZ
@4/z!
publicclass Page { .QA1'_9
wlh%{l
/** imply if the page has previous page */ BT^=p
privateboolean hasPrePage; u-bgk(u
,%zE>^~
/** imply if the page has next page */ ACFEM9 [=
privateboolean hasNextPage; 0LIXkF3^1
JDp=w,7LF
/** the number of every page */ q$s)(D
privateint everyPage; Yt_t>
;*U&lT
/** the total page number */ 2#CN:b]+
privateint totalPage; J-G)mvkv
: Q2=t!
/** the number of current page */ Q&@<?K9
privateint currentPage; gdh|X[d
T
:^OW5 d
/** the begin index of the records by the current hv#LKyp%
=i2]qj\
query */ z,@R jaX
privateint beginIndex; unnuSW#v=
$bBUL C
JE@3 UXg
/** The default constructor */ 5nmE*(
public Page(){ *$JS}Pax
x
#|t#N%
} 4
'vjU6gW
Pp4Q)2X
/** construct the page by everyPage _0\wyjjU
* @param everyPage 63t'|9^5
* */ -:Juxh
public Page(int everyPage){ BHNJH
this.everyPage = everyPage; `Cy;/95m
} NjdDImz.;s
l~@ -oE
/** The whole constructor */ m
(kKUv
public Page(boolean hasPrePage, boolean hasNextPage, Np.<&`p!
tqKX\N=5^
z}*L*Sk
int everyPage, int totalPage, >{0,dGm
int currentPage, int beginIndex){ uw`J5TND
this.hasPrePage = hasPrePage; 7L]Y.7>
this.hasNextPage = hasNextPage; wqX!7rD/g)
this.everyPage = everyPage; F7=&CW 0
this.totalPage = totalPage; uL~.#Y_jQ
this.currentPage = currentPage; E-?JHJloU
this.beginIndex = beginIndex; t-]~^s
} xR&Le/3+
rC ,ZRFF
/** f4|ir3oy
* @return zWF[cf>'
* Returns the beginIndex. 0F&(}`V
*/ VlxHZ
publicint getBeginIndex(){ _o>?\ :A
return beginIndex; bHzH0v]:
} <2^
F'bQV
y"w`yl{_
/** ^VjF W
* @param beginIndex !Bhs8eGr3
* The beginIndex to set. l<s6Uu"
*/ ]Lm?3$u$
publicvoid setBeginIndex(int beginIndex){ ]"\sd"
this.beginIndex = beginIndex; _Oc\hW
} .wQM_RZJ
^4a|gc
/** LJ*W&y(2>Q
* @return D<bHRtP
* Returns the currentPage. 2>kk6=<5'
*/ Pbakw81!~
publicint getCurrentPage(){ /)XN^Jwa;m
return currentPage; [nB4s+NX
} -JXCO<~k
-1]8f
/** BPypjS0?8
* @param currentPage ~J|B
* The currentPage to set. CVGQ<,KVW
*/ OZ Hfd7K4A
publicvoid setCurrentPage(int currentPage){ Uc]sWcR
this.currentPage = currentPage; 5uL!Ae
} %OT?2-d
}(w9[(K
/** |@pn=wW
* @return %j;mDR95
* Returns the everyPage. B3@\Ua)
*/ mP-Y9*k
publicint getEveryPage(){ N=TDywRI
return everyPage; <U2Un 0T
} f^@DuI
^wb$wtL('
/** =(p]L
* @param everyPage #PA 9bM
* The everyPage to set. $/$ 5{<
*/ !2]'S=Y
publicvoid setEveryPage(int everyPage){ c7t .
this.everyPage = everyPage; +o}mV.&