Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 o_G.J4 V
Q_uv.\*z_
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 S%%>&^5
+U6!
bu>C
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 * rs_k/2(
>/'WU79TYE
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 W
BiBtU
T@Q.m.iV4
。 <,cD EN7
msoE8YK&tg
分页支持类: e dD(s5
O>k. sO
<
java代码: +p43d:[
fwl
RwH(
l{y~N
package com.javaeye.common.util; ZGp8$Y>r
mX2Qf8
import java.util.List; cCj}{=U
wL%>
publicclass PaginationSupport { .+M4Pi
TAGqRYgi
publicfinalstaticint PAGESIZE = 30; 6SidH_&C
=CqLZ$10
privateint pageSize = PAGESIZE; * |,V$
"kN5AeRg
privateList items; dB1bf2'b#
)T2Sw z/
privateint totalCount; #D}NT*w/
]AfeaU'>
privateint[] indexes = newint[0]; isDr|g$S
Kk/qd)nk
privateint startIndex = 0; 0,VbB7 z
f:BW{Cij;y
public PaginationSupport(List items, int 02=eE|Y@
X#Hs{J~@p
totalCount){ 5SK.R;mn
setPageSize(PAGESIZE); ;,IGO7R
setTotalCount(totalCount); t(s']r
setItems(items); q|Ga
setStartIndex(0); sM-k,0z
} ,NVQ C=
YgVZq\AV"
public PaginationSupport(List items, int WMYvE\"
b
~F85U2
totalCount, int startIndex){ h],_1!0
setPageSize(PAGESIZE); G:A`
n;E0
setTotalCount(totalCount); \bfNki
setItems(items); L]9*^al
setStartIndex(startIndex); )C <sj
} %)]{*#N4
zR]l2zL3
public PaginationSupport(List items, int $e0sa=/
HPu nNsA
totalCount, int pageSize, int startIndex){ m}8c.OJ>K`
setPageSize(pageSize); QhN5t/Hr
setTotalCount(totalCount); ]V}";cm;2
setItems(items); cp]\<p('A
setStartIndex(startIndex); 6R"& !.ZF
} UXe @c@3
RD,`D!
publicList getItems(){ S{&;
return items; <sn^>5Ds
} I)n%aT fo8
2}hEBw68
publicvoid setItems(List items){ fF<~2MiKw
this.items = items; z,$^|'pP
} j].XVn,
gh3_})8c
publicint getPageSize(){ 0(HUy`]>
return pageSize; 'BtvT[KM
} `Y8F}%i[
A)'{G
publicvoid setPageSize(int pageSize){ | [P!9e
this.pageSize = pageSize; 1;S@XC>
} 1@;Dn'
rVkRU5
publicint getTotalCount(){ 51l :
return totalCount; E%2]c?N5
} >pUR>?t"
_KLKa/3
publicvoid setTotalCount(int totalCount){ ;MR8E9
if(totalCount > 0){ sYYNT*
this.totalCount = totalCount; 1Sx2c
int count = totalCount / l*":WzRGvF
i=nd][1n
pageSize; X8"4)IZ3
if(totalCount % pageSize > 0) KZ>cfv-&a
count++; 5$d>:" >
indexes = newint[count]; }k~ih?E^s
for(int i = 0; i < count; i++){ 3c}@_Yn
indexes = pageSize * kq8.SvIb
e?,n>
i; 4hz T4!15
} e
^2n58
}else{ SFv'qDA
this.totalCount = 0; DS%~'S
} F2QFQX(j
} gNUYHNzDM(
e#!%:M;4P
publicint[] getIndexes(){ C.].HQ
return indexes; lE'3U qK
} [MhKR }a
_wH>h$E
publicvoid setIndexes(int[] indexes){ ~t^
Umx"Ew
this.indexes = indexes; d<K2
\:P{}
} hK+6S3-Ez
WX6}@mS.
publicint getStartIndex(){ )0+6^[Tqq
return startIndex; 4a}[&zm(5
} lonV_Xx
=gNPS0H
publicvoid setStartIndex(int startIndex){ K*I!:1;3N
if(totalCount <= 0) z36wWdRa6
this.startIndex = 0; txE=AOY5
elseif(startIndex >= totalCount) `OFW^Esc
this.startIndex = indexes ttOk6-
xP4}LL9)
[indexes.length - 1]; >Q$ph=
elseif(startIndex < 0) vMd3#@
this.startIndex = 0; L"bZ~'y
else{ {Y-~7@
this.startIndex = indexes $vrkxn
&S,_Z/BS;
[startIndex / pageSize]; [ ?%q,>F
} 'X<4";$mU
} ZDg(D"
])}a^]0q
publicint getNextIndex(){ (\0
<|pW
int nextIndex = getStartIndex() + H2H`7 +I,
27k(`{K
pageSize; /~MH]Gh
if(nextIndex >= totalCount) 4
km^S9
return getStartIndex(); k&2=-qgVR
else sUF9_W5z
return nextIndex; z',Fa4@z
} {`QA.he.
0j_kK
publicint getPreviousIndex(){ `^52IkM)
int previousIndex = getStartIndex() - l+[:Cni
NMe{1RM
pageSize; ]?pQu '-(
if(previousIndex < 0) |>yWkq
return0; h);^4cU
else ki?h7
return previousIndex; Jy5sZ}t[
} t%;w<1E
>!6|yk`GJ
} V:$+$"|
`J1HQ!Z
#8|LPfA
wqhktgG
抽象业务类 @@)2 12
java代码: C,An\lsT
" !~o
G@.MP|
2
/** tO&ffZP8$
* Created on 2005-7-12 s{-gsSmE
*/ 7~ PL8
package com.javaeye.common.business; `&M,B=E
fes s6=k
import java.io.Serializable; B1V{3
import java.util.List; ?@
F2Kv
`
y\)X
C7
import org.hibernate.Criteria; |'q%9#
import org.hibernate.HibernateException; uMJ\
import org.hibernate.Session; JVYH b 60Z
import org.hibernate.criterion.DetachedCriteria; u.ggN=Z
import org.hibernate.criterion.Projections; |^6{3a
import }(oeNPM8
b6bs .
org.springframework.orm.hibernate3.HibernateCallback; r3W3;L
import l~6K}g?
$KK~KEZ2
org.springframework.orm.hibernate3.support.HibernateDaoS wY8:j
`ePC$Ovn
upport; w G %W{T$
V)j[`,M:
import com.javaeye.common.util.PaginationSupport; QO2cTk
m
+(W1x
C0
public abstract class AbstractManager extends rO'DT{Yt
!sb r!Qt
HibernateDaoSupport { CMXF[X)%
# ]7Lieh[5
privateboolean cacheQueries = false; ;-+q*@sa]
tAdE<).!
privateString queryCacheRegion; ^7-zwl(>?N
Oynb"T&8
publicvoid setCacheQueries(boolean ,o&C"sb
gc9R;B1
cacheQueries){ \$ytmtf5
this.cacheQueries = cacheQueries; Smr{+m a
} -8Jw_
xN 1P#
publicvoid setQueryCacheRegion(String !%iHJwS#
/Mqhx_)>A
queryCacheRegion){ ZK5nN9`
this.queryCacheRegion = M:S-%aQ_<y
Vy\Vpp
queryCacheRegion; -(qRC0V
} 2 !s&|lI
@Z jT_
publicvoid save(finalObject entity){ 0j.K?]f)h
getHibernateTemplate().save(entity); 6':iW~iI
} jD:
N)((
+yGQt3U
publicvoid persist(finalObject entity){ g'8Y5x[
getHibernateTemplate().save(entity); UUah5$Iy
} 3S^0%"fY
?'a8QJo
publicvoid update(finalObject entity){ Ql*zl
getHibernateTemplate().update(entity); Shm> r@C?
} JU 9GJ"
Gt w>R
publicvoid delete(finalObject entity){ fab'\|Y
getHibernateTemplate().delete(entity); @~3--
} dbI>\khI
A#{63_H
publicObject load(finalClass entity, I6>J.6luF9
_?{7%(C
finalSerializable id){ wQ}r/2n|^
return getHibernateTemplate().load 0> f!S` *
/jbAf ]"F;
(entity, id); ?#xl3Z ;I
} _Nx
/<isdL
Sj9fq*
publicObject get(finalClass entity, l$42MRi/
/ f%mYL
finalSerializable id){ F3tps
jQ
return getHibernateTemplate().get Lb*KEF% s
3DU1c?M:
(entity, id); ?jx]%n fV
} f:c'j`
I>c,Bo7
publicList findAll(finalClass entity){ Up9{aX
return getHibernateTemplate().find("from rzjVUPdnh
Oy6fl'FIt
" + entity.getName()); @MW@mP)#
} +y7z>Fwl
7|rH9Bc{U
publicList findByNamedQuery(finalString mU'<:gL+
D6 B-#u!M
namedQuery){ gI+8J.AG=
return getHibernateTemplate Kxe\H'rR
Y.:R-|W
().findByNamedQuery(namedQuery); 1{}p_"s>
} @AyteHK
tUn>=>cWP
publicList findByNamedQuery(finalString query, f?3-C8hU
x4_IUIgh
finalObject parameter){ _O9V"DM
return getHibernateTemplate &L o TO+
}
ueFy<F
().findByNamedQuery(query, parameter); WT
*"V<Z
} blO4)7m
exRw, Nk4
publicList findByNamedQuery(finalString query, =BJLj0=N
{U4!sJSl1
finalObject[] parameters){ +UzQJt/>>
return getHibernateTemplate SV7;B?e%Y
xR7ZqTcw
().findByNamedQuery(query, parameters); 86&M Zdv6
} 2e48L677-
\Z{tC$|H
publicList find(finalString query){ 7ZcF0h
return getHibernateTemplate().find }=R]<`Sj.j
t)SZ2G1r
(query); F^!D[:;jK
} P.~UUS
3?OQ-7,
publicList find(finalString query, finalObject kpOdyn(
"ra$x2|=}
parameter){ -4Qub{Uym
return getHibernateTemplate().find ''17(%
>XN[KPTa
(query, parameter); }\_.Mg^y
} )f8>kz(
~ |G&cg
public PaginationSupport findPageByCriteria h>Kx
6 2xOh\(
(final DetachedCriteria detachedCriteria){ \!KE_7HRu
return findPageByCriteria GwWK'F'2
3:nhZN/95T
(detachedCriteria, PaginationSupport.PAGESIZE, 0); _"DC)
} 0TN28:hcD
\PX4>/d@y
public PaginationSupport findPageByCriteria .1QGNW
5"%.8P
(final DetachedCriteria detachedCriteria, finalint gC7!cn
f-U zFlU
startIndex){ )Q2Ap&
return findPageByCriteria ;`AB-
pyEQb#
(detachedCriteria, PaginationSupport.PAGESIZE, D]]e6gF$e
Upz)iOqLi
startIndex); y6 (L=$+B
} (3e.q'
|mT%IR
public PaginationSupport findPageByCriteria dJuy Jl$*
A;cA|`b
(final DetachedCriteria detachedCriteria, finalint xj5TnE9^
1UQ,V`y
pageSize, XG#?fr}L
finalint startIndex){ `
w;Wud'*<
return(PaginationSupport) ^}
{r@F
5:PS74/
getHibernateTemplate().execute(new HibernateCallback(){ \zd[A~!
publicObject doInHibernate rfV'EjiM}
~cU1
/CW8
(Session session)throws HibernateException { *%uz LW0
Criteria criteria =
zAB= >v
{7y;s
detachedCriteria.getExecutableCriteria(session); nDi^s{
int totalCount = #H$lBCWI
V#G)w~
((Integer) criteria.setProjection(Projections.rowCount .AN1Yt
@$slGY
()).uniqueResult()).intValue(); 5OM#_.p
criteria.setProjection p22AH%
\?
/'
(null); (KI9j7
List items = $Sc _E:`]
f
)Lcs
criteria.setFirstResult(startIndex).setMaxResults w!lk&7Q7Z
XPhP1 ^>\
(pageSize).list(); Kp7DI0~
PaginationSupport ps = RvG=GJJ9
+~n:*\
new PaginationSupport(items, totalCount, pageSize, QN*|_H@h
W" =l@}I
startIndex); [%k8l~ 6
return ps; 7U7!'xU
} X~IilGL8:
}, true); sOqFEvzo1%
} GR|\OJ<2
|GMo"[
public List findAllByCriteria(final O=__w *<
v4e4,Nt
DetachedCriteria detachedCriteria){ ,^bgk
-x-
return(List) getHibernateTemplate 20I`F>-*
2hV -h
().execute(new HibernateCallback(){ J0V m&TY
publicObject doInHibernate :E}y
Pcw
pW+uVv,
(Session session)throws HibernateException { yeyDB>#Va.
Criteria criteria = 7V%P
#E+ybwA
detachedCriteria.getExecutableCriteria(session); Oj-\
return criteria.list(); .I_atv
} A~xw:[zy$a
}, true); kq X=3Zo
} KBM*7raA
P;"moluE;
public int getCountByCriteria(final 3qTr|8`s
xHt7/8wF
DetachedCriteria detachedCriteria){ W=HvMD
Integer count = (Integer) e^lX|L>o
5Pf=Uj6D
getHibernateTemplate().execute(new HibernateCallback(){ * WV=X p
publicObject doInHibernate %GTFub0F
.@fA_8
(Session session)throws HibernateException { %Bw:6Y4LZ
Criteria criteria = 2d*bF.
u<8b5An;
detachedCriteria.getExecutableCriteria(session); fY^CIb$Y
return ~~Bks{"BS
%16Lo<DPm
criteria.setProjection(Projections.rowCount F. U@8lr
bN-!&Td
()).uniqueResult(); eP"B3Jw
} ^mn!;nu
}, true); tC|?Kl7
return count.intValue(); |&"aZ!Kn
} PP{9Y Vr
} z'l
HL
JXL?.{'A
<Q(E {c3"
$F^VtCx2&
<oJ?J^
?fH1?Z\'K
用户在web层构造查询条件detachedCriteria,和可选的
7LU^Xm8
"LTw;& y
startIndex,调用业务bean的相应findByCriteria方法,返回一个 Eu' ;f_s
,r*Kxy
PaginationSupport的实例ps。 IDn<5#
-&D=4,#
ps.getItems()得到已分页好的结果集 |`
~io F
ps.getIndexes()得到分页索引的数组 zYV{ |Z
ps.getTotalCount()得到总结果数 7)QZ<fme
ps.getStartIndex()当前分页索引 r'Wf4p^Xd
ps.getNextIndex()下一页索引 C*ep8{B
ps.getPreviousIndex()上一页索引 _^Q!cB'~/`
lv=q( &
iO?AY
t3<8n;'y:
l,l qhq\
!b_(|~7Lc
7P2n{zd,
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;Tr,BfV|Bf
&u[{V R:
,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 Y >w7%N
1s(T#jh
一下代码重构了。 ,93Uji[l
"x9yb0
我把原本我的做法也提供出来供大家讨论吧: ;+XrCy!.)L
:=y5713
首先,为了实现分页查询,我封装了一个Page类: KGM__Z O.
java代码: g>h/|bw4
yn}Dj9(q
tnobqL'
/*Created on 2005-4-14*/ W9]z]6
package org.flyware.util.page; Lq5xp<
F8Ety^9>9
/** <~5O-.G]
* @author Joa l+@;f(8}
* GqxnB k1
*/ Zpg;hj5_
publicclass Page { KxK,en4)+
Op-z"inw
/** imply if the page has previous page */ uX1;
privateboolean hasPrePage; rb-ao\
Qz(2Iu{E]
/** imply if the page has next page */ |:5O|m '
privateboolean hasNextPage; N\*oL*[j
+o`%7r(R
/** the number of every page */ q~
aFV<Q
privateint everyPage; pgES)
_aevaWtEx
/** the total page number */ f;^ +q-Q
privateint totalPage; V?S}%-a
~'%d]s+q
/** the number of current page */ jKmjZz8L]%
privateint currentPage; r1< 'l
l%2VA
/** the begin index of the records by the current |K1S(m<F
^(^P#EEG
query */ zN!W_2W*
privateint beginIndex; &Tt7VYJfIV
uX_#NP/2
v_5qE
/** The default constructor */ x
t-s"A
public Page(){ (G>su
3%'`^<-V
} [T_[QU:A
n{!{,s
/** construct the page by everyPage tcj"rV{G
* @param everyPage [T r7SU#x
* */ LRHod1}mS
public Page(int everyPage){ "L]v:lg3
this.everyPage = everyPage; 3R<r[3WP
} +:@^nPfHy
$a~
/** The whole constructor */ m+'1c}n^7
public Page(boolean hasPrePage, boolean hasNextPage, Db Qp(W0
zgjgEhnvU
mbbhz,
int everyPage, int totalPage, L;opQ~g
int currentPage, int beginIndex){ lVT*Ev{&.
this.hasPrePage = hasPrePage; h>!h|Ma
this.hasNextPage = hasNextPage; L?nhm=D
this.everyPage = everyPage; sC\?{B0r
this.totalPage = totalPage; \m|5Aqs
this.currentPage = currentPage; o(e(|k
{
this.beginIndex = beginIndex; Vwp>:'Pu
} wqDf\k}'v
Se!w(Y&
/**
+!u9_?Tp
* @return x} =,'Ko}3
* Returns the beginIndex. 12#yHsk
*/ 17'd~-lE
publicint getBeginIndex(){ 25Z}.))
return beginIndex; q0%QMut%
} h$`m0-'
VE]TT><
/** Vyi.:lL _8
* @param beginIndex |e#W;q$v
* The beginIndex to set. ?cWwt~N9
*/ <UO[*_,\
publicvoid setBeginIndex(int beginIndex){ tLKf]5}f
this.beginIndex = beginIndex; $A~aNI
} u^SInanw
#Db^*
/** r(wf>w3
* @return ep3VJ"^
* Returns the currentPage. jjH2!R]^>
*/ kO`!!M[Oo
publicint getCurrentPage(){ `%[m%Y9h
return currentPage; uy2~<)
} F/Js K&&
H5d@TB,`
/** 7p'pz8n`X
* @param currentPage *?Wz/OJ0
* The currentPage to set. eptw)S-j
*/ Tr>_R%b K
publicvoid setCurrentPage(int currentPage){ -}xK>
["
this.currentPage = currentPage; MA9E??p3\
} u)EtEl7Wq
hB<(~L?A]
/** ~b*|V
* @return I3.JAoB>!
* Returns the everyPage. VXk[p
*/ /AX)n:,
publicint getEveryPage(){ ^3vI
NF
return everyPage; TPx0LDk%(
} =_E$* }
J s33S)
/** )RFY2}
* @param everyPage ,^1 #Uz8
* The everyPage to set. {gEz;:!):
*/ j-aTpN
publicvoid setEveryPage(int everyPage){ #Q_Scxf
this.everyPage = everyPage; ?gAwMP(>
} V`/c#y||
6 Yva4Lv
/** }|/<!l+;$
* @return /!5cf;kl*l
* Returns the hasNextPage. |jH Yf42Q
*/ fi'zk
publicboolean getHasNextPage(){ ~|~ 2B$JeV
return hasNextPage; `v(!IBP|
} (@BB@G
!6taOT>v
/** " 5Pqvi
* @param hasNextPage 2GigeN|1N
* The hasNextPage to set. m/g[9Y
*/ l9%ckC*q
publicvoid setHasNextPage(boolean hasNextPage){ rx#GrV*y
this.hasNextPage = hasNextPage; C@XnV=J
} jv29,46K
H2g#'SK@
/** 'g<FL`iP
* @return tG"EbWi
* Returns the hasPrePage. #Ph8?
*/ hG<W*g
publicboolean getHasPrePage(){ ^Kl<<pUaV
return hasPrePage; #="Lr4T
} 4e[ 0.2?
gi_f8RP=2a
/** r;waT@&C
* @param hasPrePage Y)S
f;
* The hasPrePage to set. 5@bmm]
*/ h=au`o&CG
publicvoid setHasPrePage(boolean hasPrePage){ F CfU=4O
this.hasPrePage = hasPrePage; Cw.DLg
} 1X&scVw
\Z/0i|
/** 8"wavh|g4
* @return Returns the totalPage. ^D
{v L
* @-1VN;N
*/ XS0NjZW
publicint getTotalPage(){ WR*<|
return totalPage; L_zB/(h
} %yVP@M
J<iiA:&J
/** lz#@_F|.*
* @param totalPage Ao9=TC'v$'
* The totalPage to set. `GooSX
*/ $L]E<
gWrP
publicvoid setTotalPage(int totalPage){ 'Hq#9?<2M
this.totalPage = totalPage; ]4_)WUS.c
} ~X) 1!Sr
`C*psS
} Pz' Zn
Zr!CT5C5
\T`iq[+6
7I@@}A
u9}LvQh_6,
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 c=:A/z{
kqS_2[=]
个PageUtil,负责对Page对象进行构造: v kW2&
java代码:
(Vy`u)gG
"4QD\k5
&K,rNH'R
/*Created on 2005-4-14*/ kkV*#IZ
package org.flyware.util.page; B}h8c
;MKfssG
import org.apache.commons.logging.Log; <:0d%YB)
import org.apache.commons.logging.LogFactory; Jy#21
j2!^iGS}
/** c6F8z75U
* @author Joa }z wHUf9q1
* Ha!]*wg#
*/ ^: V6=
publicclass PageUtil { }mQh^
l`<u\],
privatestaticfinal Log logger = LogFactory.getLog /{\mV(F(
n@| &jh
(PageUtil.class); (L8z<id<z
h<f]hJ`ep
/** zlN<yZB^
* Use the origin page to create a new page m"8Gh`Fo
* @param page (Z};(Hn
* @param totalRecords 2/G`ej!*
* @return Ru^j~Cj5
*/ dI9u:-
publicstatic Page createPage(Page page, int hXsH9R
ejPK-jxCa/
totalRecords){ >_um-w #C
return createPage(page.getEveryPage(), yBwCFn.uP-
tm280
page.getCurrentPage(), totalRecords); .UJjB}4$f
} N2S7=`5/T
1Igo9rv
/** _0]{kB.$_
* the basic page utils not including exception hiA%Tq?
lip1wR7
handler =WP`i29j9}
* @param everyPage 3XomnL{
* @param currentPage
d365{
* @param totalRecords `$,
\B
* @return page Qh.
:
N
*/ a8!/V@a
publicstatic Page createPage(int everyPage, int _;].
ZI'Mr:z4
currentPage, int totalRecords){ i=G.{.
everyPage = getEveryPage(everyPage); VY=c_Gl
currentPage = getCurrentPage(currentPage); ROB/#Td
int beginIndex = getBeginIndex(everyPage, /_MEb42&
,|
EaW& 2
currentPage); `CXAE0Fx
int totalPage = getTotalPage(everyPage, 3d|n\!1r
qhiO( !jK
totalRecords); MHVHEwr.{
boolean hasNextPage = hasNextPage(currentPage, `d[ja,
E1e#E3Yq}s
totalPage); z rV
boolean hasPrePage = hasPrePage(currentPage); * -Kf
$zvqjT:>
returnnew Page(hasPrePage, hasNextPage, KvrcO#-sL
everyPage, totalPage, H,!3s<1
currentPage, ]7`)|PJ
[j:]YR
beginIndex); .w `1;o
} Iq-+X3i
phA^ kdW
privatestaticint getEveryPage(int everyPage){ i$A0_ZJKjZ
return everyPage == 0 ? 10 : everyPage; ? }2]G'7?
} )"IBw0]
mqg[2VTRP
privatestaticint getCurrentPage(int currentPage){ fQ^45ulz
return currentPage == 0 ? 1 : currentPage; 9aE!!
(E
} "c6(=FFq
y:N
QLL>
privatestaticint getBeginIndex(int everyPage, int 9(>l trA
5Y\wXqlY
currentPage){ #*[G,s#t^
return(currentPage - 1) * everyPage; OI9V'W$
} q>T7};5m2
$~V,.RD
privatestaticint getTotalPage(int everyPage, int o1"MW>B,4
`&"-|
totalRecords){ .I@jt?6X
int totalPage = 0; FBYAd@="2
etEm#3
if(totalRecords % everyPage == 0) }?pY~f
totalPage = totalRecords / everyPage; rH9wRY(
else \B'rWk33,
totalPage = totalRecords / everyPage + 1 ; +@Oo)#V|.
Zjz< Q-
return totalPage; )vFJx[a<n`
} s:j"8ZH
?t&sT
privatestaticboolean hasPrePage(int currentPage){ A d0dg2Gw
return currentPage == 1 ? false : true; Xi]WDH \
} ,haCZH{
vpy_piG|
privatestaticboolean hasNextPage(int currentPage, Cz2OGM*mz?
5YlY=J
int totalPage){ [/}y!;3iXM
return currentPage == totalPage || totalPage == Md9b_&'
OIK14D:
0 ? false : true; >9o(84AxIH
} Hnv{sND[
*^XfEO
fI2/v<[
} KLI(Rve24
%-y%Q.;k?
sE4=2p`x
e Ir|%
} PD]e*z{Z
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 y9?~^pTx
B5>1T[T'-
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 M
<oy
&u62@ug#}
做法如下: pKf]&?FX
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 *x EcX6ZHX
;\@co5.=
的信息,和一个结果集List: 'iM;e K
java代码: 8Wn;U!qT
>E;-asD
C WJGr:}&
/*Created on 2005-6-13*/ W]!{Y'G
package com.adt.bo; (9_~R^='y
2IgTB|2
import java.util.List; L-}>;M$Y)
\{F{yq(
import org.flyware.util.page.Page; S^,1N4
N;cEf7+f
/** xjHOrr
OQ
* @author Joa v:*t5M
>
*/ KX e/i~AS
publicclass Result { -LF0%G
:DP%>H|
private Page page; t:tT Zh
DPuz'e*
private List content; Mg
H,"G
!xs.[&u8
/** C:qb-10|A
* The default constructor (fmcWHs
*/ d\aarhD8*
public Result(){ P+iZ5S\kL=
super(); ?{s!.U[T@
} d52l)8
PI>PEge!&
/** R:zPU
* The constructor using fields j4wcxZYY~
* sY4sq5'!
* @param page 2s, [DC
* @param content Txkmt$h
*/ z?$F2+f&
public Result(Page page, List content){ YfBb=rN2s
this.page = page; *vn^
W
this.content = content; l4+!H\2
} -TKS`,#
(lwrk(
/**
%{\|/#>:
* @return Returns the content. KlMrM% ;y
*/ O5HK2Xg,C
publicList getContent(){ [%(}e1T(
return content; ?bc-?<Xk
} ;Ee!vqD2
\|2 0E51B[
/** {6%vmMbJ
* @return Returns the page. Ad)Po
*/ y:Xs/RS
public Page getPage(){ NvH9?Ek"
return page; P( >*gp
} 74YMFI
}} cz95
/** 70NQ9*AAy
* @param content |4uH
* The content to set. :USN`"
*/ OgJd^
public void setContent(List content){ ~_WsjD0O
this.content = content; hS]g^S==2h
} Qs2E>C
' uvTOgP,
/** E"!I[
* @param page Xd%c00"U
* The page to set. =}N&c4I[j
*/ [+0rlmB
publicvoid setPage(Page page){ dz
fR ^Gv
this.page = page; XMb]&VvH
} &$yC+cf
} % 1Y!|306
s%h|>l[lKT
"?Dov/+Q.
n%;wQ^
C?@vBM}
2. 编写业务逻辑接口,并实现它(UserManager, :V1ttRW}52
)cA#2mlS'1
UserManagerImpl) X._skq
java代码: Q 6djfEN>
W.OcmA>x
*0>![v
/*Created on 2005-7-15*/ C^ngdba\
package com.adt.service; \7W>3
e?W-vi%
import net.sf.hibernate.HibernateException; eELJDSd
BV
O~t]:p9_
import org.flyware.util.page.Page; gycjIy@t
8S2sNpLi-g
import com.adt.bo.Result; DG&
({vy
VC%{qal;q
/** /Qh
* @author Joa o&]b\dV
*/ I&9_F%rX
publicinterface UserManager { N{ L'Q0!
GE;S5X]X
public Result listUser(Page page)throws D$C >ZF
I9S=VFhZ`
HibernateException; *1FDK{
r!H'8O!
} (,Zy2wr=
sywSvnPuYZ
3m
RP.<=
Z05kn{<a8
B/"TaXVU
java代码: H CKD0xx
;pk4Voo$
Y,1ZvUOB
/*Created on 2005-7-15*/ V_b"^911r
package com.adt.service.impl; >*DR>U
Hh^EMQk
import java.util.List; ?:@13wm
Y0nnn
import net.sf.hibernate.HibernateException; 50,`=Z
ze* =7
import org.flyware.util.page.Page; Ir%L%MuR]
import org.flyware.util.page.PageUtil; {wUbr ^
f3,qDbQyJ
import com.adt.bo.Result; &(M][Uo{|'
import com.adt.dao.UserDAO; -Ky<P<@ezm
import com.adt.exception.ObjectNotFoundException; L`sg60z
import com.adt.service.UserManager; m9yi:zT%
yT[CC>]l
/** Fjnp0:p9X
* @author Joa R]dN-'U
*/ ;/ wl.'GA
publicclass UserManagerImpl implements UserManager { hw2'.}B"(
54[#&T$S
private UserDAO userDAO; @#HB6B
pe}mA}9U
/** G6W_)YL
* @param userDAO The userDAO to set. O|Sbe%[*wW
*/ ^?+qNbK
publicvoid setUserDAO(UserDAO userDAO){ _*&I[%I5
this.userDAO = userDAO; 7j,-o
} o!6~tO=%
{ XI 0KiE
/* (non-Javadoc) Iax-~{B3AY
* @see com.adt.service.UserManager#listUser v,T:V#f^
HgGwV;W
(org.flyware.util.page.Page) a$=BX=
*/ $,Eb(j
public Result listUser(Page page)throws H1bHQB
7Shau%2C
HibernateException, ObjectNotFoundException { WD/\f$4
int totalRecords = userDAO.getUserCount(); V /.Na(C~
if(totalRecords == 0) q?R^~r
throw new ObjectNotFoundException DB~3(r?K
?g{--'L
("userNotExist"); ~^{>!wU+
page = PageUtil.createPage(page, totalRecords); }Z/[ "
List users = userDAO.getUserByPage(page); /EIQMZuYp
returnnew Result(page, users); 0Cg}yy Oz
}
saRYd{%+
O'Mo/
u1-
} xNrPj8V<Y
h6CAd-\x\
uI9eUO
'c&[ kMR
._E 6?
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 aM7e?.rU
]Cc3}+(s
询,接下来编写UserDAO的代码: d/8p?Km
3. UserDAO 和 UserDAOImpl: (jyT9'*wAT
java代码: _2-fH
R7o'V* d
=:M/hM)#
/*Created on 2005-7-15*/ vh$If0
package com.adt.dao; ~|lEi1|
m
>Rdsn~l
import java.util.List; a
Xn:hn~O
.Ei#mG-=}&
import org.flyware.util.page.Page; C3K":JB
cMfJq}C<
import net.sf.hibernate.HibernateException; n#l~B@
-k?K|w*X
/** <e?1&5 6
* @author Joa %A3ci[$g
*/ en_W4\7^
publicinterface UserDAO extends BaseDAO {
7;I;(iY
.rwa=IW
publicList getUserByName(String name)throws %{|67h
A-eRL`
HibernateException; ,/YTW@N
h ^.jK2I
publicint getUserCount()throws HibernateException; h+c9FN
"C.cU
publicList getUserByPage(Page page)throws XxY wBc'pc
-kP$S qR~
HibernateException; nb\pBl
o?g9Grk
} k|^YYi=xF
wpI"kk_@@
3s0I<cL
*=}\cw\A
?orLc,pU^
java代码: S-[S?&c`
K]'t>:G@
nh]HEG0CZJ
/*Created on 2005-7-15*/ Y<t(m$s
package com.adt.dao.impl; 8Sk$o.Gy
KTE X]
import java.util.List; Hva/C{Y
{pXqw'"1.
import org.flyware.util.page.Page; oO^=%Mc(
1=_Qj}!1
import net.sf.hibernate.HibernateException; 3>6rO4,
import net.sf.hibernate.Query; goOw.~dZ'
pLe[<N
import com.adt.dao.UserDAO; Nwg?(h#
P&h]uNu
/** R:`)*=rL%
* @author Joa HF<h-gX
*/ t2,?+ q$x
public class UserDAOImpl extends BaseDAOHibernateImpl fizL_`uMqb
+}
y"S -
implements UserDAO { 2Z-QVwa*U
N<O<wtXIj
/* (non-Javadoc) T7^?j :kJ/
* @see com.adt.dao.UserDAO#getUserByName }LY)FT4n
6lL^/$]
(java.lang.String) B%WkM\\!^
*/ RgVnx] IF
publicList getUserByName(String name)throws nwVW'M]r
8 q>
HibernateException { IN,=v+A
String querySentence = "FROM user in class /@1pm/>ZaN
/z)Nz2W
com.adt.po.User WHERE user.name=:name"; NFPWh3),f
Query query = getSession().createQuery x@@bC=iY$
8H,k0~D
(querySentence); VHG}'r9KC%
query.setParameter("name", name); &@ ${@
return query.list(); M[C)b\
} V}ls|B$Y
=imJ0V~RW
/* (non-Javadoc) L9]d$ r"
* @see com.adt.dao.UserDAO#getUserCount() TUARYJ6=
*/ A6
Rw LX
publicint getUserCount()throws HibernateException { n7|,b-
<
int count = 0; nG-DtG^z
String querySentence = "SELECT count(*) FROM +$F,!rV-s
eCiI=HcW;
user in class com.adt.po.User"; fX2OH)6U
Query query = getSession().createQuery i7e_~K
A1*\ \[
(querySentence); vnS8N
count = ((Integer)query.iterate().next viJP6fh
q0b*#j
()).intValue(); 0lOR.}]q
return count; ">5$;{;2r
} -e>Z!0
&A=c[pc
/* (non-Javadoc) z0%tBgqY(
* @see com.adt.dao.UserDAO#getUserByPage ?<T=g
/t*Q"0X5
(org.flyware.util.page.Page) Y ` Z,52
*/ h"[:$~/UJ
publicList getUserByPage(Page page)throws n(i/jW~0w
o$Y#C{wC%
HibernateException { v57<b&p26
String querySentence = "FROM user in class HA[7)T N1E
N( f0,
com.adt.po.User"; ";/ogFi
Query query = getSession().createQuery y.-Kqa~
C;%dZ
(querySentence); 2XEE/]^
query.setFirstResult(page.getBeginIndex()) xZY7X&C4
.setMaxResults(page.getEveryPage()); YI`BA`BQ8
return query.list(); R7KV
@n
} ]]e>Jym
yE~D0%Umq
} d\zUtcJwC
Ktu~%)k%
Q3Y(K\
yYP>3]z
#<s"?Y%-
至此,一个完整的分页程序完成。前台的只需要调用 `5"3Cj"M
X\>/'fC$
userManager.listUser(page)即可得到一个Page对象和结果集对象 x0K#-
5m;BL+>YE
的综合体,而传入的参数page对象则可以由前台传入,如果用 G(ZEP.h`u
i|xz
webwork,甚至可以直接在配置文件中指定。 J#q^CWN3R
jp1e3 Cg
下面给出一个webwork调用示例: .8GXpt^U(
java代码: Ypxp4B
uvw1 _j?
@%YbptT}
/*Created on 2005-6-17*/ _'<FBlIN
package com.adt.action.user;
}Oqt=Wm
$~VIx% h
import java.util.List; URt+MTU[
ZE=
Yn~XM
import org.apache.commons.logging.Log; `U|zNizO
import org.apache.commons.logging.LogFactory; C\OZs%]At
import org.flyware.util.page.Page; {B e9$$W,
TB= _r(:l+
import com.adt.bo.Result; Ix<!0!
vk
import com.adt.service.UserService; cd=K=P}p
import com.opensymphony.xwork.Action; 7\ZSXQy1W
cYXL3)p*Q
/** 0c8_&
* @author Joa !w@i,zqu
*/ -@Urq>^v T
publicclass ListUser implementsAction{ HLdHyK/S
B6KG\,'|
privatestaticfinal Log logger = LogFactory.getLog )heHERbJ
4%|r$E/TQ
(ListUser.class); !H<%X~|,
I6gduvkXi4
private UserService userService; -yTIv*y
5uOz #hN
private Page page; Aa]3jev
4tx6h<L#s
privateList users; z.?slYe[
M4CC&?6\
/* >oaL -01i
* (non-Javadoc) 6j+X@|2^
* n3qRt
* @see com.opensymphony.xwork.Action#execute() %Pj}
*/ {`T^&bk
publicString execute()throwsException{ H
SGz-
Result result = userService.listUser(page); -_eG/o=M
page = result.getPage(); Li$2 Gpc/
users = result.getContent(); !_;J@B
return SUCCESS; <"xqt7f
} ZLPj1L
q)KOI`A
/** H*+7{;$
* @return Returns the page. eH[i<Z
*/ K{V.N<