Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 `rb>K
j6g@tx^)'
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 vl:J40Kfn
'bu )M1OLi
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 >t <pFh
OP! R[27>
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 #E$X,[ZFo
}Hcx=}j
。 p
&(OZJT
1;lmu]I>)
分页支持类: @T:faJ5\'
B_^]C9C|
java代码: x,8<tSW)Z
#=,imsW)
SO{p ;g
package com.javaeye.common.util; nFM@@oA
2oVV'9;B
import java.util.List; DN8}glVxV
1S:|3W
publicclass PaginationSupport { SJ?)%[(T
\Kavw
publicfinalstaticint PAGESIZE = 30; 'Ot,H_pE
~i~%~doa
privateint pageSize = PAGESIZE; e8P-k3a"5:
gfa[4
z
privateList items; Q2|p\rO
_\8qwDg"#e
privateint totalCount; Pbu{'y3J
v?:: |{
privateint[] indexes = newint[0]; kH948<fk3
[xZU!=
privateint startIndex = 0; ) R2XU
OJO!FH)
public PaginationSupport(List items, int r[txlQI9
ZKpvDH'
totalCount){ y9l*m~
setPageSize(PAGESIZE); 5|8^9Oe5
setTotalCount(totalCount); sLL7]m}
setItems(items); /JJw 6[N
setStartIndex(0); T7*wS#z)h
} !#yq@2QX
&1|?BZv
public PaginationSupport(List items, int O(Jj|Z
"3CJUr:Q
totalCount, int startIndex){ ~P*4V]L^
setPageSize(PAGESIZE); /t%u"dP"T~
setTotalCount(totalCount); O9M{ ).
setItems(items); 0s#Kp49-
setStartIndex(startIndex); MGpt}|t-
} f3MRD4+-
&&>tf%[
public PaginationSupport(List items, int .)tSg
]T:;Vo
totalCount, int pageSize, int startIndex){ eU@Cr7@,|
setPageSize(pageSize); ]< l6s
setTotalCount(totalCount); Me5{_n
setItems(items); :[l\@>H1tX
setStartIndex(startIndex); .Ajzr8P
} R`8@@}
o{:xp r=(
publicList getItems(){ b*kfWG-6t
return items; OhZgcUqQ8
} u+m,b76
NpP')m!`}
publicvoid setItems(List items){ -Z-f1.Dm5
this.items = items; )u%je~Vw
} "SxLN
8.:
K>Fqf
+_
publicint getPageSize(){ bUwn}_7b
return pageSize; 2}6%qgnT-
} l |2D/K5
SLL3v,P(7
publicvoid setPageSize(int pageSize){ /1UOT\8U
this.pageSize = pageSize; \Q?ip&R
} 'dG%oDHX]P
]}="m2S3
publicint getTotalCount(){ `r"+644
return totalCount; gV;H6"
} e}Vw!w
B!]2Se2G
publicvoid setTotalCount(int totalCount){ !|hoYU>@2L
if(totalCount > 0){ LkruL_E>
this.totalCount = totalCount; &)wiKh"$
int count = totalCount / }Db[ 4
d[^KL;b?6
pageSize; (& "su3z
if(totalCount % pageSize > 0) ipnV$!z
count++; HAz By\M{
indexes = newint[count]; |077Sf|
for(int i = 0; i < count; i++){ 3rW|kkn
indexes = pageSize * 6 gL=u-2
&F:IIo7
i; O|IG_RL]
} BF*kb2"GZ6
}else{ $
i)bq6
this.totalCount = 0; ^ 2GHe<Y
} 2,2Z`X
} t.8 GT&p
+Mewo
publicint[] getIndexes(){ P9Yy9_a|x
return indexes; 8
;d$54
b
} vy2Q g
Y`7~Am/r;&
publicvoid setIndexes(int[] indexes){ j`'`)3f
this.indexes = indexes; *K!|@h{60
} /n~\\9#3
W:,4 :|3
publicint getStartIndex(){ 9O`
m,t
return startIndex; ^H{R+}
} (/!r(#K0,'
&X@Bs-
publicvoid setStartIndex(int startIndex){ sIG7S"k>p
if(totalCount <= 0) Y?CCD4"qn
this.startIndex = 0; uzmk6G
v
elseif(startIndex >= totalCount) ]w T 7*( Y
this.startIndex = indexes S:4crI
`e9$,h|4
[indexes.length - 1]; Q?ahr~qo
elseif(startIndex < 0) B[=(#W
this.startIndex = 0; 4a0:2 kIKa
else{ [${
QzO
this.startIndex = indexes MObt,[^W
'j^xbikr
[startIndex / pageSize]; ]V %.I_
} D0k
8^
} \P} p5k[
H1<>NWm!v7
publicint getNextIndex(){ 3~,d+P
int nextIndex = getStartIndex() + ]-oJ[5cQ0v
mK+IEZV<3
pageSize; HX'FYt/?t
if(nextIndex >= totalCount) N8qDdr9p?c
return getStartIndex(); )vmA^nU>
else V@>r*7\F
return nextIndex; GRb*EeT
} '1,,)U#6E
5w %_$x
publicint getPreviousIndex(){ =U8a ?0
int previousIndex = getStartIndex() - {Q+gZcu
)1N 54FNO
pageSize; Hsih[f
if(previousIndex < 0) QK0h6CX
return0; }kw/W#)J
else kKD`rfyG\
return previousIndex; #-pc}Y|<
} {o5V7*P;_
hjaT^(Y
} .s#;s'>g
1h6^>()^
6x"Q
aQI^^$9g
抽象业务类 `D9]*c
!mO
java代码: :4~g;2oag
^TMJ8`e
`:P
/** [SJ6@q
* Created on 2005-7-12 R@Gq)P9?
*/ 5H=ko8fZ=
package com.javaeye.common.business; ~/mwx8~
T+N|R
import java.io.Serializable; [M.f-x:
import java.util.List; k>t)g-,2
(`SRJ$~f
import org.hibernate.Criteria; USFDy
import org.hibernate.HibernateException; 8ElKD{.BU8
import org.hibernate.Session; 8G5Da|\
import org.hibernate.criterion.DetachedCriteria; zBO(`=|
import org.hibernate.criterion.Projections; [((;+B
import wApMzZ(X2y
i)#s.6.D>
org.springframework.orm.hibernate3.HibernateCallback; LL|7rS|o
import ,J`'Y+7W
nW;g28
org.springframework.orm.hibernate3.support.HibernateDaoS aM7uBx\8 5
dt~YW
upport; ZeG_en ;
]skkoM
import com.javaeye.common.util.PaginationSupport; ?"z]A7<Hj
mxb06u_
public abstract class AbstractManager extends n}s~+USZX
3Tn)Z1o
HibernateDaoSupport { 5 H#W[^s"
\rVQQ|l
privateboolean cacheQueries = false; 7'
S @3
=)hVn
privateString queryCacheRegion; p7:{^
AfG/JWSo}
publicvoid setCacheQueries(boolean qc#)!
1 sPdz
L
cacheQueries){ tzy'G"P|
this.cacheQueries = cacheQueries; upeU52@\
} C7H/N<VAq
>J|]moSVA
publicvoid setQueryCacheRegion(String a_h]?5
:c
{EdH$l>94
queryCacheRegion){ 0rGSH*(
this.queryCacheRegion = |+`c3*PV
~rjTF!
queryCacheRegion; 5OoN!TEM
} }du XC[ 6
N)&4Hy
publicvoid save(finalObject entity){ >DPB!XA3
getHibernateTemplate().save(entity); OgF+OS
} w
'3#&k+
gKOOHUCb
publicvoid persist(finalObject entity){ 9b?SHzAa
getHibernateTemplate().save(entity); nenU)*o
} }E`dZW*!!
G;f/Tch
publicvoid update(finalObject entity){ ' oFxR003
getHibernateTemplate().update(entity); d|T!v
} gocrjjAHk
"*,XL
uv>
publicvoid delete(finalObject entity){ QXF
aAb=(7
getHibernateTemplate().delete(entity); 5=e@d:Sz
} K-&V,MI
ZNYH#mJX*
publicObject load(finalClass entity, p$ bnK]
E9V5$
finalSerializable id){ B75k^ohfj
return getHibernateTemplate().load mrV!teP
N?X^O#[
(entity, id); MLFKH
} d~h:~
>a3p >2
publicObject get(finalClass entity, V5 U?F6
>J u]2++lx
finalSerializable id){ :_Eqf8T
return getHibernateTemplate().get Jk0r&t7
pIbdN/z
(entity, id); wO2_DyMm@
} nYbhy}y
$ "Bh]-
publicList findAll(finalClass entity){ pHoEa7:
return getHibernateTemplate().find("from (|wz7AY2
R0oKbs{
" + entity.getName()); :{(w3<i
} $<ld3[l i
~^+0
publicList findByNamedQuery(finalString .Vq)zi1<
]tY
^0a
namedQuery){ Dde]I_f}
return getHibernateTemplate M4xi1M#%
N25V]
().findByNamedQuery(namedQuery); ;;A2!w{}[i
} e L.(p
k^<
s|y:UgD
publicList findByNamedQuery(finalString query, 85;b9k&\M
GJqE!I,.
finalObject parameter){ 9;xM%
return getHibernateTemplate TNJG#8 n%Y
N?X~ w <
().findByNamedQuery(query, parameter); |pa$*/!NT
} uytE^
@(C1_
publicList findByNamedQuery(finalString query, GElvz'S~
UU8pz{/
finalObject[] parameters){ W5#611
return getHibernateTemplate I7^zU3]Ul
pu,?<@0YK
().findByNamedQuery(query, parameters); zS]8V?`
} 7)%+=@
67y Tvr@a
publicList find(finalString query){ h_d<!
return getHibernateTemplate().find CkswJ:z)sc
.G o{1[
(query); cwV]!=RtO
} 5[n(7;+gw
gl&5l1&
publicList find(finalString query, finalObject r <
cVp^
3Tq\BZ
parameter){ WMMO5_Mz
return getHibernateTemplate().find Y?534l)j
Mc!Xf[
(query, parameter); ,C {*s$
} ,sGZ2=M}J
fqu}Le
public PaginationSupport findPageByCriteria \n9zw'
rxme(9M
(final DetachedCriteria detachedCriteria){ MQ)L:R`L
return findPageByCriteria `>o?CIdp
{,OS-g
(detachedCriteria, PaginationSupport.PAGESIZE, 0); }h 3K@R
} `mT$s,:h
s}j1"@
public PaginationSupport findPageByCriteria _bD/D!|
Tlj:%yK2
(final DetachedCriteria detachedCriteria, finalint fm~kM
J
7RDDdF E!
startIndex){ |j3'eW&=
return findPageByCriteria 0j(M*
sl
<5=JE*s$NS
(detachedCriteria, PaginationSupport.PAGESIZE, <)*2LBF@]
SR*wvQnOx
startIndex); ?|e'Gbb_
} >%E([:$A
m0{ !hF[^
public PaginationSupport findPageByCriteria |y<),j6
5d@t7[]
(final DetachedCriteria detachedCriteria, finalint ( )sTb>L
5sPywk{
pageSize, LI)!4(WH
finalint startIndex){ tRpEF2
return(PaginationSupport) %zU`XVNN+
=uDgzdDyE
getHibernateTemplate().execute(new HibernateCallback(){ -*2Mf Mh
publicObject doInHibernate &_5tqh
c#N<"cy>
(Session session)throws HibernateException { _lW+>xQ
Criteria criteria = !EQ@#qW/
y0~Ia:y
detachedCriteria.getExecutableCriteria(session); 5X.e*;
int totalCount = fJZp?e"
0b91y3R+
((Integer) criteria.setProjection(Projections.rowCount (Toq^+`c
d*pF> j
()).uniqueResult()).intValue(); wB>r(xQ'
criteria.setProjection L!_ZY
;v
(null); jEXW
List items = DP/J(>eG
$hxNhI
criteria.setFirstResult(startIndex).setMaxResults }bU8G '
/MQU
>&
(pageSize).list(); VDB;%U*D
PaginationSupport ps = T!W~n
ZC
sS
TPMh
new PaginationSupport(items, totalCount, pageSize, aAu>Tn86D.
8vk..!7n}
startIndex); ,7,g%?_P
return ps; w<9>Q1(
} 5BR5X\f0
}, true); juBw5U<
} ;d$qc<2uA
U}Hwto`R
public List findAllByCriteria(final x ]5@>5
]\RRqLDzkg
DetachedCriteria detachedCriteria){ Y,8KPg@W
return(List) getHibernateTemplate P\CDd=yWc
)Z+{|^`kJ
().execute(new HibernateCallback(){ VCy5JH
publicObject doInHibernate I &* _,d
YJxw 'U
>P
(Session session)throws HibernateException { &/.hx(#d
Criteria criteria = V E2tq k%
+MK6zf
detachedCriteria.getExecutableCriteria(session); c^8o~K>w84
return criteria.list(); TST4Vy3
} >Q,zNs
}, true); ECa$vvK
m
} 9s
+z B
-VDo[Zy
public int getCountByCriteria(final nxQ?bk}*d
vFrt|JC_{
DetachedCriteria detachedCriteria){ acd:r%y
Integer count = (Integer) :"0J=>PH:
b{DiM098
getHibernateTemplate().execute(new HibernateCallback(){ PCc|}*b
publicObject doInHibernate /\mKY%kyh
zT~B6
(Session session)throws HibernateException { (wRBd
Criteria criteria = t<:D@J]a
#0b&^QL
detachedCriteria.getExecutableCriteria(session); b4Y8N"hL%
return RnfXN)+P
6) \dBOz
criteria.setProjection(Projections.rowCount mxwdugr`
2WM\elnA
()).uniqueResult(); u!N{y,7W)
} h06ku2Q
}, true); I>h<b_y
return count.intValue(); y?[snrK G
} nD"~?*Lt
} )_zlrX
RANPi\]
z41_oG7
4"\yf
=j0x.fSe
ANH4IYd3
用户在web层构造查询条件detachedCriteria,和可选的 (B>Zaro#
0@1:M
startIndex,调用业务bean的相应findByCriteria方法,返回一个 ZA#y)z8!E
cd;NpN
PaginationSupport的实例ps。 5TBI<K
:&'{mJW*{t
ps.getItems()得到已分页好的结果集 u"$a>S_
ps.getIndexes()得到分页索引的数组 0BkV/v1Uc
ps.getTotalCount()得到总结果数 PM$Ee #62R
ps.getStartIndex()当前分页索引 vd#,DU=p!
ps.getNextIndex()下一页索引 2>S~I"o0
ps.getPreviousIndex()上一页索引 ?3sT"r_d@
MWuXI1
BH0!6Oq
jj\ [7 O*
{gf>*
e{G_GycH
PX".Km p.
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ApPy]IdwX
go)p%}s
,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 U6 82Th
?SY<~i<K-
一下代码重构了。 71B3a
YTY%#"
我把原本我的做法也提供出来供大家讨论吧: 4YbC(f
e/e0d<(1
首先,为了实现分页查询,我封装了一个Page类: dhRJg"vrQ
java代码: {j(4m
X7aXxPCq1
](r
^.k,R
/*Created on 2005-4-14*/ & %}/AoU
package org.flyware.util.page; TW`mxj_J2
2]jPv0u
/** >L2*CV3p
* @author Joa <D /a l9
* ucg$Ed
*/ g"t^r3
publicclass Page { V*B0lI7`B
4".J/I5u
/** imply if the page has previous page */ .PVLWW
privateboolean hasPrePage; eVnbRT2y&
si/er"&o
/** imply if the page has next page */ qc!xW,I
privateboolean hasNextPage; 4sY[az
9rj('F&1
/** the number of every page */ OKY+M^PP
privateint everyPage; cV$lobqO
L@|#Bbmx
/** the total page number */ y{rn-?`{
privateint totalPage; C@dGWAG
F%6*Df;cSe
/** the number of current page */ #0MK(Ut/
privateint currentPage; ;R1B9-,
l[n@/%2
/** the begin index of the records by the current ^JhFI*
e&J3N
query */ 9$tl00
privateint beginIndex; N2~$rpU3
=Q?f96T
|1V2tx
/** The default constructor */ X7cWgo66T
public Page(){ *8!w&ME+.
A|vP$zy
} Gj6. Iv
rnvQ<671W
/** construct the page by everyPage NXgRNca
* @param everyPage }z'DWp=uN
* */ Tx+ p8J|Yr
public Page(int everyPage){ g5R,% 6
this.everyPage = everyPage; #4y,a_)
} A o3HX
i>Iee^_(
/** The whole constructor */ 7Jx%JgF
public Page(boolean hasPrePage, boolean hasNextPage, )*[
""&
AUAI3K?
d7~j^v)=^
int everyPage, int totalPage, 9y+[o
int currentPage, int beginIndex){ NiTJ}1 l
this.hasPrePage = hasPrePage; )1_(>|@oi
this.hasNextPage = hasNextPage; 6+%-GgPf
this.everyPage = everyPage; %_tk7x
this.totalPage = totalPage; xURw,
this.currentPage = currentPage; }'`xu9<
this.beginIndex = beginIndex; :HZ;Po
} _'c+fG
\
%8Yyj{^!(
/** _W9&J&l0so
* @return rbh[j@s@
* Returns the beginIndex. zUQe0Gc.b^
*/ XM!M%.0WS
publicint getBeginIndex(){ h*'d;_(,
return beginIndex; ]31$KBC
} F50JJZ
eUs-5
L
/** )VY10R)$
* @param beginIndex 5+y`P$K@
* The beginIndex to set. "A7<XN<
*/ 0ny{)Sd6um
publicvoid setBeginIndex(int beginIndex){ R92R}=G!
this.beginIndex = beginIndex; K`gc 4:A
} l:z};
FQ## 397
/** Qtnv#9%Vi
* @return EW;1`x
* Returns the currentPage. ;.0LRWcJ
*/ `e*61k5
publicint getCurrentPage(){ b Fn(w:1Q
return currentPage; a 2E t,WA%
} a>(~ C'(<
N?^_=KE@
/** .D3`'K3t{[
* @param currentPage ^N{X "
* The currentPage to set. ++k J\N{
*/ ]-EN/V
publicvoid setCurrentPage(int currentPage){ _Y7:!-n}
this.currentPage = currentPage; x:C@)CAr
} 'RQiLUF
Loc8eToZ
/** +I.v!P!^
* @return @SQceQfB
* Returns the everyPage. R_9 o!sTZ
*/ =SL^>HS.fo
publicint getEveryPage(){ S| "TP\o
return everyPage; JilKZQmk
} R25-/6_V>
GDmv0V$6
/** +WdL
* @param everyPage 4L$};L
* The everyPage to set. i]@c.QiFN
*/ 85Dm8~
publicvoid setEveryPage(int everyPage){ D{3fhPNU<b
this.everyPage = everyPage; P|v ?
} lR[z<2w\
6,zDBax
/** ]wR6bEm7
* @return dL(4mR8
* Returns the hasNextPage. D0KELAcY
*/ ]eD [4Y\#t
publicboolean getHasNextPage(){ E]?2!)mgce
return hasNextPage; d~,n_E$q;
} yW:AVqE)t
YOlH*cZtg
/** klo^K9!
* @param hasNextPage S}O5l}E
* The hasNextPage to set. U#$:\fT
*/ P8u"T!G
publicvoid setHasNextPage(boolean hasNextPage){ ?qIGQ/af&
this.hasNextPage = hasNextPage; H<{*ub4'L*
} @@; 1%z
S~} +ypV
/**
Jb6&
* @return qWkx:-g]
* Returns the hasPrePage. W -3w7^
*/ o=@ UXi
publicboolean getHasPrePage(){ Hj1k-Bs&'w
return hasPrePage; DSTx#*
} !Am
=v=>
nT)~w
s
/** BHIM'24bp
* @param hasPrePage l2r>|CGQ[
* The hasPrePage to set. vevx|<9,
*/ ?SB5b ,
publicvoid setHasPrePage(boolean hasPrePage){ np= J:v4
this.hasPrePage = hasPrePage; %"{?[!C ?
} VJGwd`qo*A
4bWfx_0W
/** }el,^~
* @return Returns the totalPage. &4[<F"W>47
* `c> A>c|
*/ :> x:(K
publicint getTotalPage(){ ^=3 ^HQ'Zm
return totalPage; hg!x_Eq|
} 2Sv>C `FMU
5'),)
/** p+!f(H
* @param totalPage ^1()W,B~w
* The totalPage to set. E:%>0FE
*/ YALyZ.d
publicvoid setTotalPage(int totalPage){ Sw/J+FO2
this.totalPage = totalPage; Xk;Uk[
} wX@H
&)<s
L/c4"f|.*v
} T$f:[ye]Z
zv&ePq\#
m<~>&mWr
9$8X>T^
L,tZh0
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ]U#JsMS
6_x}.bkIx=
个PageUtil,负责对Page对象进行构造: 3{I=.mUUm
java代码: ^"PfDTyA
:A,O(
e?|d9;BO
/*Created on 2005-4-14*/ ~>lOl/n 5
package org.flyware.util.page; &%@/Dwr
RT1{+:l
import org.apache.commons.logging.Log; [9'|7fdU
import org.apache.commons.logging.LogFactory; Fa6H(L3
j'#)~>b
/** 9@JlaY)0
* @author Joa Xq[:GUnt
* xq8}6Q
*/ X^u4%O['
publicclass PageUtil { 3}v0{c
x;<oaT$X
privatestaticfinal Log logger = LogFactory.getLog [%HYh7ua<
v/QEu^C
(PageUtil.class); 2(@LRl>:
[P (rY
/** 9(i0"hS^
* Use the origin page to create a new page &Xj {:s#
* @param page 7uWJ6Wk
* @param totalRecords
zjZ;xn
* @return m4wPuW
*/ nNkyOaK*4
publicstatic Page createPage(Page page, int : Bdi pc
@&/s~3
totalRecords){ y 8Ei=[
return createPage(page.getEveryPage(), //ne']L
!3O,DhH>MC
page.getCurrentPage(), totalRecords); /F\>Z]
} ){?mKB5
*C[4 (DmB
/** ez{P-qB
* the basic page utils not including exception Lg\8NtP
Gsx^j?
handler >eYU$/80
* @param everyPage U^vUdM"
* @param currentPage PT
0Qzg
* @param totalRecords F5:2TEA
* @return page T)$6H}[c
*/ h0'8NvalQ
publicstatic Page createPage(int everyPage, int d m/-}
LC~CPV'F
currentPage, int totalRecords){ ^TuP=q5?
everyPage = getEveryPage(everyPage); G~b`O20N
currentPage = getCurrentPage(currentPage); bW,BhUb,|
int beginIndex = getBeginIndex(everyPage, [a#?}((
?uNTUU,
currentPage); 4i ~eTb
int totalPage = getTotalPage(everyPage, #`fi2K&]j
0:7v/S!:
totalRecords); `8$:F4%P
boolean hasNextPage = hasNextPage(currentPage, r&H=i
IG2 `9rR
totalPage); 60Xl.
boolean hasPrePage = hasPrePage(currentPage); [qO5~E`;
2ID*U d*
returnnew Page(hasPrePage, hasNextPage, $9LGdKZ_D
everyPage, totalPage, B;Q`vKY
currentPage, yoq\9* ?u^
YD0vfwh
beginIndex); yBXkN&1=%;
} P>yG/:W;
Zi2Eu4p l{
privatestaticint getEveryPage(int everyPage){ =H.<"7
return everyPage == 0 ? 10 : everyPage; nm{'HH-4
} \FY/eQ*07
E-BOIy,
privatestaticint getCurrentPage(int currentPage){ 0XBBA0tq
return currentPage == 0 ? 1 : currentPage; E.zYi7YUKK
} Pl>nd)i`
d=xI
privatestaticint getBeginIndex(int everyPage, int ;L\!g%a
JO<gN=
[
currentPage){ 0{U ]STj
return(currentPage - 1) * everyPage; @M1yBN
} z<3}TD
:JTRRv
privatestaticint getTotalPage(int everyPage, int L~?,6
8S[<[CH
totalRecords){ /Gh
x2B
int totalPage = 0; 9^b7jw
)n[`Z#
if(totalRecords % everyPage == 0) ;Wfv+]n9
totalPage = totalRecords / everyPage; l"~h1xk~
else vJ# rW8y
totalPage = totalRecords / everyPage + 1 ; !"o1ve`{
N>F2
c)rm
return totalPage; On2Vf*G@|
} kG|>_5
)|59FOWg
privatestaticboolean hasPrePage(int currentPage){ 5W:Gl?$S}
return currentPage == 1 ? false : true; sTYuwna~
} b}EYNCw_7S
(|ct`KU0#
privatestaticboolean hasNextPage(int currentPage, lyOrM7Gs
y<'2BTf
int totalPage){
bSeL"
return currentPage == totalPage || totalPage == n41\y:CAo
{$u@6&
B
0 ? false : true; gs`27Gih
} FzsS~C$wH{
.H[Lo>
Ue>A
} >gS5[`xRE
VQG /g\
q6m87O9
pO 7{3%
|+$j(YuH
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 vt(}ga
F_M~!]<na
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Xx9~
~YT>:Np
做法如下: (`uC"M Lk
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 o<Rxt
*B
c-3Y SrY
的信息,和一个结果集List: -V<=`e
java代码: =vqE=:X6
&s6(3k
9cw4tqTm
/*Created on 2005-6-13*/ =Y=^]ayO/
package com.adt.bo; 46.q anh
[<3Q$*Ew
import java.util.List; EiIFVP
[&]YVn>kj
import org.flyware.util.page.Page; {*5;:QnT
t6,M
/** m;tY(kO
* @author Joa |]]pHC_/W
*/ Jz:W-o
publicclass Result { Y"]e H{
[y&h_w.
private Page page; @gl%A&a
MCWG*~f
private List content; RZ,<D I
i5~ /+~
/** &oK/]lub
* The default constructor Q,M/R6i-
*/ 2dV\=vd
public Result(){ 83 ^,'Z
super(); PUFW^"LV
} .o,51dn+ s
w]+BBGYQKb
/** ?` ZGM
* The constructor using fields ZC\.};.
*
"ppb%=
* @param page 5+Zx-oWq_
* @param content EuimZW\V
*/ 1o"oa<*_
public Result(Page page, List content){ XKPt[$ab
this.page = page; 9|kEq>d
this.content = content; p6eDd"Y
} c402pj
oe_[h]Hgl
/** 5KPPZmO
* @return Returns the content. ;(iUY/ h[h
*/ g9r5t';
publicList getContent(){ W0?Y%Da(4m
return content; 51(`wo>LS
} d=5}^v#4
WUOPYYW<o
/** $P}]|/Yb
* @return Returns the page. F*jjcUk
*/ '>WuukC
public Page getPage(){ Xy8ie:D
return page; |9i/)LRXe
} Z_4H2HseL
p$!+2=)gY
/** s"Pk-Dv
* @param content i\R\bv[9
* The content to set. $q@RHcj
*/ q!h*3mNm
public void setContent(List content){ )b2E/G@X&
this.content = content; yW=hnV{
} `R=_t]ie
Vi-!E
/** )1yUV*6
* @param page ujHzG}2z
* The page to set. ]B.,7
*/ .gsu_N_v
publicvoid setPage(Page page){ KL\=:iWA
this.page = page; $=g.-F%*=
} n YMf[kW
} Cq;K,B9
<IkD=X
rpP+20 v
YHv,Z|.w
0~L8yMM
2. 编写业务逻辑接口,并实现它(UserManager, U!UX"r
qxCL
UserManagerImpl) 2d J)4
java代码: .1q~,}toX
3/|{>7]1
% |Gzht\
/*Created on 2005-7-15*/ &l}xBQAL
package com.adt.service; T7Qd
I[K%b
X%\6V;zR#
import net.sf.hibernate.HibernateException; B46H@]d#7K
\]:NOmI^'
import org.flyware.util.page.Page; ghd[G}
j
tkPi)QR
import com.adt.bo.Result; Ty`=U>K|
f%%En5e+
/** Q_h+r!b
* @author Joa (=/L#Yg_
*/ ScmzbDu
publicinterface UserManager { yW,#&>]# |
gl{PLLe[}
public Result listUser(Page page)throws +q?0A^C>
Nm :lC%>X
HibernateException; 2o3k=hKS
~ilBw:L-3
} ^|12~d_.T
Y%cA2V\#m
7Z :l;%]K
8[P6c;\
l8Iy03H
java代码: 7(iRz
~5qZs"ks
f6A['<%o
/*Created on 2005-7-15*/ F"? *@L
package com.adt.service.impl; ?BZ`mrH^
?U[nYp}"v
import java.util.List; $W]guG
TZ_'nB~
import net.sf.hibernate.HibernateException; *1]k&#s
_[Wrd?Z
import org.flyware.util.page.Page; 4U1fPyt
import org.flyware.util.page.PageUtil; 4!W?z2ly~R
t-m,~Io W
import com.adt.bo.Result; !x /Z"
import com.adt.dao.UserDAO; Pb&+(j
import com.adt.exception.ObjectNotFoundException; Jy
NY *
import com.adt.service.UserManager; Z 2jMBe
-.3k
vL
/** exU=!3Ji
* @author Joa XQ y|t"Vq>
*/ *G"#.YvE
publicclass UserManagerImpl implements UserManager { Y-k~ 7{7
[4yQbqe;
private UserDAO userDAO; 0s[3:bZ\Ia
qCT\rZU
/** d(tf: @
* @param userDAO The userDAO to set. \5c -L_
*/ $ =a$z"
publicvoid setUserDAO(UserDAO userDAO){ 3sIM7WD?
this.userDAO = userDAO; jJC((1|
} JT_B@TO\
9uoj3Rh<
/* (non-Javadoc) B>21A9&
* @see com.adt.service.UserManager#listUser `r$WInsDu
UoT}m^ G
(org.flyware.util.page.Page) ITPpT
*/ SytDo (_=W
public Result listUser(Page page)throws &Y2P! \\2
,B>b9,~3a
HibernateException, ObjectNotFoundException { f=Y9a$.:M
int totalRecords = userDAO.getUserCount(); N2Hb19/k
if(totalRecords == 0) 8uW:_t]q
throw new ObjectNotFoundException PX/0 jv
?2>v5p
("userNotExist"); .Sw'Bo!Ee
page = PageUtil.createPage(page, totalRecords); H5t`E^E
List users = userDAO.getUserByPage(page); @x
]^blq
returnnew Result(page, users); zhL,BTH
} ?E@[~qq_
6;V1PK>9
} &h[}5
p[:%Ck"$7
^PpFI
BVeNK=7m%
k;X1x65uP
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 zwK;6&(W
]`9K|v
询,接下来编写UserDAO的代码: =%G[vm/-)
3. UserDAO 和 UserDAOImpl: (fb\A6
java代码: Lwk-
W4Q]<<6&
ogbdt1
/*Created on 2005-7-15*/ z5w|+9U
package com.adt.dao; .q }k
nmrk-#._@9
import java.util.List; S3wH
M
9h pM*wt
import org.flyware.util.page.Page; 6%1o<{(%f
T+!kRigN~P
import net.sf.hibernate.HibernateException; ?!-im*~w
X.|0E87
/** $4,6&dwg
* @author Joa #0H[RU?
*/ >Sah\u`
publicinterface UserDAO extends BaseDAO { 63$m& ]x
essW,2,rjC
publicList getUserByName(String name)throws ;Bi{;>3
G"wQ(6J@
HibernateException; O,#[m:Ejb
!%9I%Ak^
publicint getUserCount()throws HibernateException; f
d5~'2
X|G+N(`|(
publicList getUserByPage(Page page)throws Ry3 f'gx
9B0"GEwrs
HibernateException; Bk<P~-I
*h9vMks
o
} s50ln&2
#IDCCD^1=
^123.Ru|t
w7u >|x!
^Yz05\
java代码: ZZ7U^#RT
d5hE!=
=<xbE;,0
/*Created on 2005-7-15*/ k=_@1b-
package com.adt.dao.impl; W -&5
v
z& jDO ex
import java.util.List; ~V)E:(
CVp<SS(
import org.flyware.util.page.Page; HbVLL`06*
V;(LeuDH|
import net.sf.hibernate.HibernateException; #CmBgxg+M
import net.sf.hibernate.Query; Y1IlH8+0
O2f2Fb$B7
import com.adt.dao.UserDAO; fO nvC*
U)8]pUI+/P
/** O1,[7F.4g
* @author Joa 37Y]sJrs$
*/ _#B/#^a
public class UserDAOImpl extends BaseDAOHibernateImpl eH{ 9w8~
6Tnzg`0I
implements UserDAO { ]9Hy
"#Fz
FeLP!oS>
/* (non-Javadoc)
V;jz0B
* @see com.adt.dao.UserDAO#getUserByName /G ;yxdb
>Z%`&D~u
(java.lang.String) Y2n*T
KXI,
*/ M='Kjc>e
publicList getUserByName(String name)throws `m^OnH
qZe"'"3M
HibernateException { VWa(@A
String querySentence = "FROM user in class Y{=@^4|]
=d}3>YHS
com.adt.po.User WHERE user.name=:name"; v!Z 9T
Query query = getSession().createQuery CgC wM=!r
4aC#Cv:0
(querySentence); ZD(gYNi
query.setParameter("name", name);
U,BBC
return query.list(); L8ke*O$
} T^_9R;
D2bUSRrb
/* (non-Javadoc) .&y1gh!=
* @see com.adt.dao.UserDAO#getUserCount() X[<9+Q-&
*/ at!?"u
publicint getUserCount()throws HibernateException { :F&WlU$L
int count = 0; &
j43DYw4
String querySentence = "SELECT count(*) FROM 7}k8-:a%
C#>C59
user in class com.adt.po.User"; tUQ)q
Query query = getSession().createQuery d/1XL[&
c3##:"wr
(querySentence); S J5kA`
count = ((Integer)query.iterate().next
s25012
SCij5il%
()).intValue(); 2B7&Ll\>
return count; )Yml'?V"
} ?}[keSEh>
VM[8w`
/* (non-Javadoc) D3PF(Wx
* @see com.adt.dao.UserDAO#getUserByPage il~,y8WTU{
jPfoI-
(org.flyware.util.page.Page) /7^~*
*/ H;2pk
publicList getUserByPage(Page page)throws (&(f`c@I
PW}.`
HibernateException { Cp%|Q.?
String querySentence = "FROM user in class EeO{G*pq
W=!f
com.adt.po.User";
U{EW +>
Query query = getSession().createQuery 4%TC2Laii
N!AFsWV
(querySentence); ;Peyo1
query.setFirstResult(page.getBeginIndex())
cO:x{~
.setMaxResults(page.getEveryPage()); {\B!Rjt[T
return query.list(); %[J( ,rm
} |{
kB`
iwbjjQPr
} V~;YV]1Y
S4w/
kml3
\
(,2^T'$J
H<
j+-u4b
t(Uoi~#[
至此,一个完整的分页程序完成。前台的只需要调用 #XsqTK_nk
+-hmITJv
userManager.listUser(page)即可得到一个Page对象和结果集对象 Fr~xN!
e\<I:7%Rg
的综合体,而传入的参数page对象则可以由前台传入,如果用 ~J|0G6H
V;"'!dVX
webwork,甚至可以直接在配置文件中指定。 {8' 5
' vwBG=9C
下面给出一个webwork调用示例: 6{M.S}.^
java代码: x?3p3[y
Z(L>~+%
t.cplJF&Ue
/*Created on 2005-6-17*/ _3hEYeh
package com.adt.action.user; EO5Vg
gP3[=a"\
import java.util.List; )Ii=8etdv
?Rdi"{.wI
import org.apache.commons.logging.Log; o! 8X< o
import org.apache.commons.logging.LogFactory; Z]tz<YSkG
import org.flyware.util.page.Page; \4ZQop
wQ5__"D
import com.adt.bo.Result; ?V0IryF;
import com.adt.service.UserService; Oe$C5KA>LW
import com.opensymphony.xwork.Action; Nx99dr
6
Qmtb2
/**
Dg@6o
* @author Joa LE;c+(CAU
*/ qVfOf\x.e
publicclass ListUser implementsAction{ *$QUE0
yZ`\.GgC^&
privatestaticfinal Log logger = LogFactory.getLog (~jOtUyT
WI%,m~
(ListUser.class); _/Hu'9432
-a3C3!!
private UserService userService; N$?q Aek
YW*ti|u|w
private Page page; mU!c;O
FQ5# v{
privateList users; %]-tA,u
W/ERqVZR]
/* R$q:Ct
* (non-Javadoc) m*1=-"P
* 4h|vd.t
* @see com.opensymphony.xwork.Action#execute() C<3An_Dy
*/ '
{Q L`L
publicString execute()throwsException{ #u~8Txt
Result result = userService.listUser(page); R#0UwRjeF
page = result.getPage(); d$!ibL#o
users = result.getContent(); y=t
-/*K
return SUCCESS; &:rf80`z.
} (j(6%U
R7#B_^ $
/** J&Ah52
* @return Returns the page. n}"MF>zDK
*/ ^Kn}{m/3Y
public Page getPage(){ hQ9VcS6=gD
return page; j:0z/gHp$
} `sSI; +
k]Yd4CC2
/** B9]KC i
* @return Returns the users. \n}cx~j
*/ [,VD^\
publicList getUsers(){ gD-<^Q-
return users; xu3qX"
} Ra/S46$
Ta_#Rg*!
/** =7a9~&|
* @param page sPut@4[S
* The page to set. z;T?2~g!
*/ ~MOIrF
publicvoid setPage(Page page){ 9BP-Iet
this.page = page; -{HA+ YL H
} 4g|}]K1s
FbF P
/** (f7R~le
* @param users &T{+B:*v
* The users to set. yJ?6B LJi
*/ _di[PU=Vh
publicvoid setUsers(List users){ Au9Rr3n
this.users = users; %k9GoX_
} BRzrtK
Z\n
nVM=
/** bO9X;}\6
* @param userService >mz<=n
* The userService to set. HZ/e^"cpM
*/
KrB"2e+J
publicvoid setUserService(UserService userService){ Bx)4BPaN
this.userService = userService; opd^|xx0
} ?e0ljx;
} "~XAD(T6
alyWp
ol-U%J
+ps(9O/B>
1jDN=hIl
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, QN":Qk(,q
[&51m^
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 m)V%l0
^I7iEv
么只需要: dj 4:r!5_
java代码: 29:] cL(5
5LR
k)@t
umI@ej+D
<?xml version="1.0"?> y-9Mm9J
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 12.|E d*72
*y0TtEd;
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 05Ak[OOU>
S3$&}I <
1.0.dtd"> BKi@c\Wb
p[>!;qI
<xwork> }Ge$?ZFH
RGsgT ^
<package name="user" extends="webwork- \Cx2$<8
3v\}4)A[
interceptors"> 0
*2^joUv
]v=A}}kS
<!-- The default interceptor stack name <m'W{n%Pp
4S5U|n
--> ,?S1e#
<default-interceptor-ref +87|gC7B
PKJ w%.-
name="myDefaultWebStack"/> dSkM A
}"Clv/3_
<action name="listUser" Qu|H_<8g
8MU+i%hd
class="com.adt.action.user.ListUser"> I;FHjnn(
<param EV/DJ$C }
)\Am:?RH;
name="page.everyPage">10</param> DZ"'GQSg
<result 7v't# =
^VOFkUp)
name="success">/user/user_list.jsp</result> evjj~xkte
</action> GCZx-zD~>
xa8;"Y~"bg
</package> Lcb5^e?'Q
Y7BmW+
</xwork> zcGmru|k
TophV}@B`
>cJix
1
u.;l=tzz
VkFMr8@|
cDS\=Bf
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 u:.w/k%+
-Gy=1W`09
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Y
\ Gx|
R"W5R-
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 |yS %
2D UY4Ti
SP.k]@P
0RgE~x!hI
F_G .$aCc
我写的一个用于分页的类,用了泛型了,hoho fJOwE
g|
$7" Y/9Y
java代码: 0nbY~j$A=
(@m/j2z
BMug7xl"
package com.intokr.util; -^+fZBU;
^hNl6)hR
import java.util.List; 9HB+4q[
xpX<iT>5u
/** ~y{_NgMo
* 用于分页的类<br> ;* QK^ #
* 可以用于传递查询的结果也可以用于传送查询的参数<br> .do8\
* ~[%_]/#&%z
* @version 0.01 ncqAof(/
* @author cheng oR7[[H.4
*/ /% g+|C
public class Paginator<E> { bmu] zJ
privateint count = 0; // 总记录数 _o[fjd
privateint p = 1; // 页编号 pT{is.RM
privateint num = 20; // 每页的记录数 LTxP@pr
privateList<E> results = null; // 结果 ^hXm=r4ozR
KRz~3yH{c
/** wx^Det
* 结果总数 :_}xN!9LA
*/ kDol 1v`
publicint getCount(){
E;}&2 a
return count; 9U8x&Z]P
} ,Qx]_gZ`
`Fie'[F5,)
publicvoid setCount(int count){ `JO>g=,4
this.count = count; DQ(0:r
} ~m_{&,CA.
`;Ho<26
/** yts@cd`$
* 本结果所在的页码,从1开始 R2v9gz;W
* 3~{I/ft
* @return Returns the pageNo. 2xf#@`U
*/ ?a#Gn2
publicint getP(){ _V4O#;%?
return p; ,Kl:4 Tv
} <rtKPlb//
/jNvHo^B
/** fcxg6W'
* if(p<=0) p=1 P0y DL:X[
* v^ "qr?3V
* @param p 3_<l`6^Ns/
*/ ").gPmC
publicvoid setP(int p){ $33E-^
if(p <= 0) $TfB72
p = 1; (?m{G Q
this.p = p; 2TUV9Z
} (>vyWd]
O 2-n-
/** 6#7hMQ0&;O
* 每页记录数量 md*U
*/ ,VS(4
publicint getNum(){ )7 q"l3e"u
return num; FY^2 Y
} k:I,$"y4
OHi.5 (
/** tPl 4'tW_
* if(num<1) num=1 w]t'2p-'
*/ }[Z'Sg]s
publicvoid setNum(int num){ g3].STz6w
if(num < 1) OKAU*}_
num = 1; 9j|v
D
this.num = num; +@=V}IO
} K(i}?9WD
tPQ|znB|
/** r[4n2Mys
* 获得总页数 pd:7K'yaw
*/ "h#R>3I1)
publicint getPageNum(){ dpTsTU!\
return(count - 1) / num + 1; =B9-}]DDO
} 5]>*0#C
S
H,]8[qT<
/** 8'u9R~})
* 获得本页的开始编号,为 (p-1)*num+1 h*%FZ}}`q
*/ D3cJIVM
publicint getStart(){ o>_})WM1[
return(p - 1) * num + 1; ZA+dtEE=f9
} uG^CyM>R`
^#d\HI
/** AY{KxCrb^
* @return Returns the results.
'g!T${
*/ #h?IoB7
publicList<E> getResults(){ q)i %*IY
return results; ?D6uviQg
} ?>Sv_0
Ss+F
public void setResults(List<E> results){ wkM1tKhy/
this.results = results; /QY F|%7!
} .26mB
Xr
K f/[Edn
public String toString(){ ~.aR=m\#
StringBuilder buff = new StringBuilder 4T31<wk
gom!dB0J
(); (da`aRVDp
buff.append("{"); =SXdO)%2
buff.append("count:").append(count); F%h3?"s
buff.append(",p:").append(p); 8@;]@c)m
buff.append(",nump:").append(num); zMR)w77
buff.append(",results:").append Ea&|kO|
A#.
%7S
(results); xIGq+yd(
buff.append("}"); >G:Q/3jh
return buff.toString(); H].|K/-p
} 1Ng+mT
>\d&LLAe
} =p8uP5H
BB6[(Z
^O18\a