Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 DFqVZ
=/HTe&
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 B4 # gT
;#?+i`9'q
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 @nF#\
|Oe$)(`|h
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 o=doL{#
YCB=RT]&`
。 TM$`J
l@%7]
0!T
分页支持类:
p:^;A/D
n!\&X9%[8
java代码: Yy8%vDdJO
XZ&q5]PJI
Hk;) l3oB
package com.javaeye.common.util; \o,`@2H+'
1)wzSEV@
import java.util.List; \~ h7
o@G
<[X|ke
publicclass PaginationSupport { To19=,:
D'+kzb@
publicfinalstaticint PAGESIZE = 30; q9c:,k
t5pf4M7
privateint pageSize = PAGESIZE; vZpt}u
hSDuByoi
privateList items; d.uJ}=|
G@igxnm}
privateint totalCount; u!&Vbo? .B
@[4 Tdf
privateint[] indexes = newint[0]; 3EKqXXzOB
u9"1%
privateint startIndex = 0; r z%=qY
Awad!_VdHS
public PaginationSupport(List items, int C.$`HGv
<w d+cPZQr
totalCount){ +kKfx!
setPageSize(PAGESIZE); OQON~&~
setTotalCount(totalCount);
D=nuK25
setItems(items); [/ E_v gZ
setStartIndex(0); w%[`'_[
} PuhFbgxy
w|>O!]K]
public PaginationSupport(List items, int \{ G1d"n
9+\3E4K
totalCount, int startIndex){ sC Fqz[I
setPageSize(PAGESIZE); YRYAQj/7
setTotalCount(totalCount); \P_1@sH=
setItems(items); <Vk^fV
setStartIndex(startIndex); `\:92+
} Zv*Z^; X9
Ncu\;K\N
public PaginationSupport(List items, int =kUN ^hb
L+PrV y
totalCount, int pageSize, int startIndex){ Q2)z1'Wv
setPageSize(pageSize); 3!0Eh8ncI
setTotalCount(totalCount); .4"9o%
setItems(items); +`==US34
setStartIndex(startIndex); ]3C&l+m$ot
} *1}'ZEaJ
zM^ux!T=
publicList getItems(){ Brh<6Btl
return items; HKk;oG
} $g55wG F
A`4j=OF\
publicvoid setItems(List items){ A|V
|vT7cb
this.items = items; I%43rdoPe
} wY2#xD
{4g1Wr5=
publicint getPageSize(){ B1oy,'
return pageSize; %QUV351H
} zlmb_akJ
uuzDu]Gwu
publicvoid setPageSize(int pageSize){ jZcjiOX
this.pageSize = pageSize; /H=fK
} 3VbQDPG
&_
Ewu@4
publicint getTotalCount(){ _gK@),de
return totalCount; ?w1_.m|8u
} ul+
+h4N
&%`IPhbT
publicvoid setTotalCount(int totalCount){ x"~F=jT
if(totalCount > 0){ *Wv]DV=\
this.totalCount = totalCount; '2a }1?
int count = totalCount / FS r`Y
W?!(/`J]
pageSize; pJx88LfR
if(totalCount % pageSize > 0) gEtDqq~y@
count++; VkT8l4($X<
indexes = newint[count]; Z.$ncP0s
for(int i = 0; i < count; i++){ !}^c.<38Q
indexes = pageSize * ?'p`Qv
b&A+`d
i; X~Uvh8O
} A5tY4?|
}else{ J[;c}
this.totalCount = 0; /] ce?PPC
} ; )O)\__"-
} 5UR$Pn2a2
a <FzHCw
publicint[] getIndexes(){ @#1k+tSA,
return indexes; <wxI>T }b
} ;RW!l pGjP
~Rk%M$E9
publicvoid setIndexes(int[] indexes){ Q3\j4;jI(
this.indexes = indexes; }8p;w T!
} qr$=oCqa
|&3m '"(
publicint getStartIndex(){ 49~5U+x;
return startIndex; p-UACMN&c
} Gk*Mx6|N
/}r%DND'
publicvoid setStartIndex(int startIndex){ Zgt, 'T
if(totalCount <= 0) fzRzkn:=
this.startIndex = 0; Z&@X4X"q
elseif(startIndex >= totalCount) Y.3]vno?X
this.startIndex = indexes rAwq$!x x
3Tg
[indexes.length - 1]; rv1kIc5Za<
elseif(startIndex < 0) ej4 7'#EY
this.startIndex = 0; GptJQ=pV
else{ s<H0ka@
this.startIndex = indexes F*o{dLJ)
;#P@(ZVT
[startIndex / pageSize]; Vc$x?=
} C[gCwDwl
} 5Y#yz>B@ ]
U_m<W$"HF
publicint getNextIndex(){ ooreforr
int nextIndex = getStartIndex() + mQtGE[
k/=J<?h0
pageSize; I1BVqIt1i
if(nextIndex >= totalCount) ,h5\vWZ
return getStartIndex(); JGX E{FT
else $SRpFz5y$
return nextIndex; *4Y1((1k
} +^Eruv+F
YH&`+ +
publicint getPreviousIndex(){ IUAx*R
int previousIndex = getStartIndex() - r#JE7uneT
e3"GC_*#
pageSize; HsGXb\
if(previousIndex < 0) @X?DHLM
return0; zJ93EtlF
else M9HM:
return previousIndex; SGre[+m~m
} n'9Wl'
fchsn*R%-
} f)l:^/WP+
Q4Zuz)r*
0z #'=XWk
v{Al>v}}n
抽象业务类 <iuESeDG
java代码: !qS~YA
c [sydl
x:\+{-
/** 0f&B;?)!
* Created on 2005-7-12 7"@^JxYN
*/ d&4ve Lu
package com.javaeye.common.business; ExeD3Zj
@X+m,u
import java.io.Serializable; L15?\|':Y
import java.util.List; y^zII5|s
y<0zAsT
import org.hibernate.Criteria; a\>+!Vq
import org.hibernate.HibernateException; "3.v(GVr
import org.hibernate.Session; ug{@rt/"Z
import org.hibernate.criterion.DetachedCriteria; /2l&D~d"
import org.hibernate.criterion.Projections; WHeyE3}p
import (RVe,0y
M<^]Ywq*p
org.springframework.orm.hibernate3.HibernateCallback; _QBN/KE9
import mivb}cKM
|a4cER.'2^
org.springframework.orm.hibernate3.support.HibernateDaoS 39to5s,
+ Ac.@!X}%
upport; WJWi'|C4
g%Bh-O9\
import com.javaeye.common.util.PaginationSupport; /Cy4]1dw
7]W6\Z
public abstract class AbstractManager extends 8C]K36q
fh_+M"Y0`
HibernateDaoSupport { N8x[8Rp
[As9&]Bv5
privateboolean cacheQueries = false; W*S}^6ZT`
%O6r
privateString queryCacheRegion; cq]JD6937
JguPXHa0
publicvoid setCacheQueries(boolean >[}lC7 z,
4>
k"$l/:
cacheQueries){ V=^B7a.;>
this.cacheQueries = cacheQueries; VyX5MVh
} !LI6_Oq
/pY-how%!
publicvoid setQueryCacheRegion(String OQW%nF9~
"DaE(S&
queryCacheRegion){ OfG/7pw5%B
this.queryCacheRegion = 88Nx/:#Y*
6/Iq@BZ&
queryCacheRegion; :eIi^K z[
} |RjAp.pm
Ri>4:V3K
publicvoid save(finalObject entity){ ;w/@_!~
getHibernateTemplate().save(entity); ~c,CngeL0
} T:T`M:C.
>$$z 6A[
publicvoid persist(finalObject entity){ QPX&P{!g
getHibernateTemplate().save(entity); O22Q
g
} _'8P8T&
W4;/;[/L
publicvoid update(finalObject entity){ (}g4}A@x
getHibernateTemplate().update(entity); xU/7}='T
} NSawD.9mV
:V3z`}Rl
publicvoid delete(finalObject entity){ CvHE7H|-{
getHibernateTemplate().delete(entity); xKR\w!+Z'
} XGuxd
]p8zT|bv
publicObject load(finalClass entity, cX!C/`ew>
X+1Mv
finalSerializable id){ jme`Tyd
return getHibernateTemplate().load 6ao~f?JZ
2HUw^ *3
(entity, id); %pIP#y[4
} TZ63=m
IRGcE&m
publicObject get(finalClass entity, 6hMKAk
b)@D@K"5
finalSerializable id){ E!'6vDVC:
return getHibernateTemplate().get Sn
S$5o
EugRC
(entity, id); ,Nt^$2DZW
} HfZ ^ED"}
(3Q$)0t
publicList findAll(finalClass entity){ [^Bjmw[7
return getHibernateTemplate().find("from m]vS"AdX
)s,LFIy<A
" + entity.getName()); Uks%Mo9on
} pdB\D
Y)@Y$_
publicList findByNamedQuery(finalString -)Bvx>8fq-
6DU~6c=)
namedQuery){ m.p$f$A_
return getHibernateTemplate )Gavjj&uJ
D Qz+t
().findByNamedQuery(namedQuery); _1Q6FI5iR
} N8pV[\f
pHuR_U5*?
publicList findByNamedQuery(finalString query, @R}3f6@67
Um}AV
finalObject parameter){ jz`3xFy *]
return getHibernateTemplate Y0.'u{J*
d!w3LwZ
().findByNamedQuery(query, parameter); ]Zt ]wnL+
} #CPLvg#
)=sbrCl,C/
publicList findByNamedQuery(finalString query, (8aj`> y
=Q{?!
finalObject[] parameters){ e@qH!.g)
return getHibernateTemplate ]/kpEx
5VP0Xa ~
().findByNamedQuery(query, parameters); 04jvrde8-O
} nj0sh"~+
t/Y0e#9,
publicList find(finalString query){ CvmIDRP*
return getHibernateTemplate().find %s"&|32
RYA@{.O
(query); m0As t<u
} w6Nnx5Ay
aUzCKX%>C
publicList find(finalString query, finalObject ;<N:! $p
&}[P{53sr
parameter){ Qw:!Rw,x
return getHibernateTemplate().find i?Pnyi
@U18Dj[
(query, parameter); 7M~sol[*
} fCx(
4[@YF@_=M
public PaginationSupport findPageByCriteria s6@mXO:H^
E I zy
(final DetachedCriteria detachedCriteria){ }VZExqm)
return findPageByCriteria m<hP"j
!CWe1Dm
(detachedCriteria, PaginationSupport.PAGESIZE, 0); P2a5<#_|
} &K\80wGK
N=BG0t$
public PaginationSupport findPageByCriteria VwE4:/7YN
N
o6!gZ1
(final DetachedCriteria detachedCriteria, finalint ##=$$1Ki
ve
ysW(z
startIndex){ :R,M Y"(
return findPageByCriteria 'ZW(Hjrd
WJOoDS!i
(detachedCriteria, PaginationSupport.PAGESIZE, W~'xJ
)Xjn:
startIndex); t` "m@
} &bW,N
Lj3o-@\*j
public PaginationSupport findPageByCriteria 5,1<A@H
::oFL#+
(final DetachedCriteria detachedCriteria, finalint e4tIO
fz=?QEG
pageSize, ,r~+
9i0N
finalint startIndex){ TC?B_;a
return(PaginationSupport) qh~bX
i!
?eIb7O
getHibernateTemplate().execute(new HibernateCallback(){ ;>v.(0FE6
publicObject doInHibernate HU $"o6ap
3F2IL)Hn
(Session session)throws HibernateException { )x|;%.8FX7
Criteria criteria =
=\oH=
f
2h
detachedCriteria.getExecutableCriteria(session); D*%am|QL
int totalCount = 7y'":1
R+M =)Z
((Integer) criteria.setProjection(Projections.rowCount 0SIC=p=J
,-#MEr
()).uniqueResult()).intValue(); ST*h{:u&A
criteria.setProjection \Fz9O-jb4
}=^ ,c
(null); t )zd'[
List items = 2tq2
Cs6`lX >
criteria.setFirstResult(startIndex).setMaxResults N)X Tmh2v|
hC<ROD
(pageSize).list(); c@t?R$c
PaginationSupport ps = .11l(M
y&NqVR=
new PaginationSupport(items, totalCount, pageSize, P8d
rwF$aR>9
startIndex); !=dz^f.{
return ps; PM\Ju]
} 2LwJ%!
}, true); <~smBd
} u\*9\G
v~nKO?{
public List findAllByCriteria(final GcVQz[E
Pd91<L
DetachedCriteria detachedCriteria){ u"v7shRp:
return(List) getHibernateTemplate ]01`r/->\
U]3!"+Y1P
().execute(new HibernateCallback(){ VgHO&vU
publicObject doInHibernate }_D .Hy5
TA[%eMvA
(Session session)throws HibernateException { pR
S!
Criteria criteria = s@\3|e5g
h*S"]ye5
detachedCriteria.getExecutableCriteria(session); C >*z^6Gz
return criteria.list(); nrl?<4_
} ?v2_7x&
}, true); +A3/^C0
} S#/BWNz|
\*$^}8
public int getCountByCriteria(final X7*F~LFrj
>XgoN\w
DetachedCriteria detachedCriteria){ =g#PP@X]D!
Integer count = (Integer) fd)8lK[KJ"
(p{X.X+
getHibernateTemplate().execute(new HibernateCallback(){ A({czHLhN5
publicObject doInHibernate [DaAvN^0A
!l'nX
(Session session)throws HibernateException { I{IB>j}8
Criteria criteria = lJK]S=cd
iuV4xyp
detachedCriteria.getExecutableCriteria(session); R$:-~<O
return #
&v4c
Jq_\r'YE
criteria.setProjection(Projections.rowCount iJTG+gx
!:+U-mb*
()).uniqueResult(); ('z=/"(l
} Za@\=}Tt
}, true); ufL,Kq4
return count.intValue(); ~?/7:S
}
qCI&H7u@
} 8{4'G$6
2"6L\8hd2
lU1SN/'zx
IogLkhWX
WAn@8!9
=-dnniKW4
用户在web层构造查询条件detachedCriteria,和可选的 +wQ5m8E
i@/% E~ W
startIndex,调用业务bean的相应findByCriteria方法,返回一个 Vz mlKVE
2tz4Ag
PaginationSupport的实例ps。 NZGO8u
kHK<~srB
ps.getItems()得到已分页好的结果集 %jAc8~vW?
ps.getIndexes()得到分页索引的数组 |6AR!
ps.getTotalCount()得到总结果数 h#zm+( [B*
ps.getStartIndex()当前分页索引 K E\>T:
ps.getNextIndex()下一页索引 LsR<r1KDJ
ps.getPreviousIndex()上一页索引 ca=MUm=B
kV8R.Baf3
t_/qd9Jv
n^'d8Y(
{r&r^!K;
P.(UbF d'
C5=^cH8
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 R/{h4/+vJ
^aaj=p:cV
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 wW TuEM
#mH28UT
一下代码重构了。 WDNj7
B)k/]vz)*D
我把原本我的做法也提供出来供大家讨论吧: e\z,^
9Zx| L/\
首先,为了实现分页查询,我封装了一个Page类: ;$eY#ypx
java代码: IlEU6Rs
z{.&sr>+v
Fmn_fW6
/*Created on 2005-4-14*/ ;4+z~7Je]^
package org.flyware.util.page; S*r }oX0
d/NjY[` 5+
/** i@{b+5$
* @author Joa j\#)'>"
* D[T\_3W
*/ ]_ LAy
publicclass Page { ZrYRLg
d3oRan}z
/** imply if the page has previous page */ QKk7"2t|
privateboolean hasPrePage; "dG*HKrr
lyowH{.N"3
/** imply if the page has next page */ ;&b=>kPlZ
privateboolean hasNextPage; wKW.sZ!S1
uxW |&q
/** the number of every page */ n~,6!S
privateint everyPage; mv<cyWp
QIwO _[Q
/** the total page number */ BT:b&"AR[
privateint totalPage; T+V:vuK
)x5w`N]lm
/** the number of current page */ X56.Y.
privateint currentPage; G$`hPNSh
lz).=N}m
/** the begin index of the records by the current 2V @ pt
DUf. F
query */ ?r0>HvUf!l
privateint beginIndex; i;2V
+SFo2Wdr43
B)DtJf
/** The default constructor */ pfk)_;>,
public Page(){ yWYsN
6%VRQ#g!
} %e:
hVU
_T^@,!&
/** construct the page by everyPage r^d:Po
* @param everyPage 'kCr1t
* */ Mc|UD*Z
public Page(int everyPage){ )=h+5Z>E1
this.everyPage = everyPage; r2;+ACwWf_
} *fDhNmQ `
:as2fO$?
/** The whole constructor */ B?XqH_=0L
public Page(boolean hasPrePage, boolean hasNextPage, G{s
q|1
%?`$#*f\%
yzCamm4~0
int everyPage, int totalPage, ;#2yF34gv
int currentPage, int beginIndex){ p\|*ff0
this.hasPrePage = hasPrePage; gDsb~>rb|
this.hasNextPage = hasNextPage; pu+jw<7
this.everyPage = everyPage; 9<!Ie^o?
this.totalPage = totalPage; XgZ.UT
this.currentPage = currentPage; /`B:F5r
this.beginIndex = beginIndex; 8z"*CJ@
} Pu|3_3^
r7:4|6E
/** ]$WwPDZ
* @return jUX0sRDk
* Returns the beginIndex. w`K=J!5y2g
*/ [,ns/*f3R
publicint getBeginIndex(){ 1A\N$9Dls
return beginIndex; 5@@ilvwzz
} Ut^ {4_EC
]EPFyVt~3
/** kEM|;&=_
* @param beginIndex =ET |h}I
* The beginIndex to set. EJ`"npU
*/ <-m[0zgq
publicvoid setBeginIndex(int beginIndex){ ;JQ;LbEn
this.beginIndex = beginIndex; V17SJSC-
} Vq<\ixRi
Qc]Ki3ls
/** nhP ua&
* @return Mu]1e5^]
* Returns the currentPage. <C,lHt
*/ LL^WeD_Y
publicint getCurrentPage(){ uMe]].04
return currentPage; vCS D1~V_
} 8!(09gW'>
{]6Pd`-
/** S
7 *LV;
* @param currentPage "WE*ED
* The currentPage to set. m3E`kW|
*/ NvqIYW
publicvoid setCurrentPage(int currentPage){ V1Opp8
this.currentPage = currentPage; '6zD`Q
} zBTyRL
l
R9`37(c9+
/** Tweku}D7
* @return 6<h
==I
* Returns the everyPage. %RS8zN
*/ 8\/$cP"<^
publicint getEveryPage(){ I=G-(L/&
return everyPage; sV`!4
u7%}
} <UC_QPA\
JcDcYB
/** {N2MskK
* @param everyPage QpZCU]
* The everyPage to set. hiQ #<
*/ \hr2#!
publicvoid setEveryPage(int everyPage){ +XP9=U*g
this.everyPage = everyPage; 'Wz`P#/
} `!A<XiAOmM
qRnD{g|{1
/** \7U'p:h=U
* @return z IT)Hs5
* Returns the hasNextPage. Z& W*@(dX
*/ dFVx*{6
publicboolean getHasNextPage(){ 6(0ME$
return hasNextPage; U1^3 &N8
} UsQh+W"?
PyQ
P K,
/** >o,l/#z
* @param hasNextPage _k O<|ev
* The hasNextPage to set. Pof]9qE-y
*/ 5|_El/G
publicvoid setHasNextPage(boolean hasNextPage){ NPjNkpWm&=
this.hasNextPage = hasNextPage; jWNF3\
} T6M=BkcP
w)7 s]Ld
/** (F=q/lK$
* @return n>k 1D
* Returns the hasPrePage. _Qd CV`
*/ 6O\a\z
publicboolean getHasPrePage(){ -a\[`JHi
return hasPrePage; gEISnMH
} nv'YtmR
HyGu3
/** VbfTdRD-
* @param hasPrePage wzf%~ats
* The hasPrePage to set. w
tSX(LNY
*/ V_"UiN"o
publicvoid setHasPrePage(boolean hasPrePage){ Hkzx(yTi
this.hasPrePage = hasPrePage; <:ptNGR
} ?M9?GodbP.
w
21g&
/** Yc p<N>)
* @return Returns the totalPage. , .]1N:
* D/&nEMp6
*/ S pIdw0
publicint getTotalPage(){ KvY1bMU!
return totalPage; +[Bl@RHe^
} '
o(7@
O/Mx$Q3re
/** .!Q*VTW
* @param totalPage 9^g?/8
* The totalPage to set. nxhn|v
*/ ,~*pPhQ8m
publicvoid setTotalPage(int totalPage){ "Ta"5XW
this.totalPage = totalPage; m5
l,Lxj
} k7)<3f3&S.
7u<C&Z/
} FwwOp"[~t
ypLt6(1j%
K+3+?oYKH
^8V8,C)
+j(7.6ia
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 ;.{J>Q/U,
s_
%LU:WC
个PageUtil,负责对Page对象进行构造: 8iUYZF
java代码: cceh`s=cU
0S#T}ITm4Z
|Ng}ZLBM
/*Created on 2005-4-14*/ J936o3F_
package org.flyware.util.page; g=e~YM85
khVfc
import org.apache.commons.logging.Log; MeDlsO
import org.apache.commons.logging.LogFactory; Qb#iT}!p%
COH9E\ZGF
/** tvcM<
e20
* @author Joa W.nr&yiQ
* !SdP<{[
*/ &Ivf!Bgm{Z
publicclass PageUtil { $ Gs|Z$(
5
51p*
B2
privatestaticfinal Log logger = LogFactory.getLog ;4k/h/o1#
b8&z~'ieR
(PageUtil.class); kE854Ej
Bk@&k}0
/** \[<8AV"E-'
* Use the origin page to create a new page h3j`X'
* @param page ( "wmc"qH
* @param totalRecords r#NR3_@9
* @return uJU;C.LX
*/ FJ2~SKWT
publicstatic Page createPage(Page page, int %mRnJgV5k
Y2W{?<99
totalRecords){ 1AQ3<
return createPage(page.getEveryPage(), 9#1Jie$
2`A\'SM'4
page.getCurrentPage(), totalRecords); AQD`cG
} KqvM5$3
Nt~G
{m
/** $|VD+[jSV
* the basic page utils not including exception ?OC&=}
ne# %Gr
handler KouIzWf.
* @param everyPage <G#Q f|&
* @param currentPage Dv}VmC""
* @param totalRecords h3V;
J
* @return page naM=oSB(
*/ :.crES7<[X
publicstatic Page createPage(int everyPage, int O
+Xu?W]
$?y\3GX
currentPage, int totalRecords){ gH/(4h
everyPage = getEveryPage(everyPage); {cmV{ 4Yx
currentPage = getCurrentPage(currentPage); YbJB.;qK
int beginIndex = getBeginIndex(everyPage, },,K6*P
NW~`oc)NS
currentPage); PDb7 h
int totalPage = getTotalPage(everyPage, ]Uul~T
B:fulgh2ni
totalRecords); QURpg/<U
boolean hasNextPage = hasNextPage(currentPage, .=@CF8ArG
@+Anp4%;Y
totalPage); /\m>PcPa
boolean hasPrePage = hasPrePage(currentPage); j9|1G-CM
P]H4!}M
returnnew Page(hasPrePage, hasNextPage, ?S'Wd=
everyPage, totalPage, rhC
x&L
currentPage, d[sY]_ dj
v4r%'bA
beginIndex); `Gh#2U
} ^`f qK4<
r[3 2'E
privatestaticint getEveryPage(int everyPage){ !DXK\,;>
return everyPage == 0 ? 10 : everyPage; *_eY +\j
} IhXP~C6
,j%feC3
privatestaticint getCurrentPage(int currentPage){ y~<_ux,
return currentPage == 0 ? 1 : currentPage; T*rz#O
} [q~3$mjQ
]EEac
privatestaticint getBeginIndex(int everyPage, int d>Ky(wS
p;)@R$*
currentPage){ 4x_#
1 -
return(currentPage - 1) * everyPage; iM~qSRb#mJ
} #./8inbG
xn}HB
privatestaticint getTotalPage(int everyPage, int -o YJ&r
[~k!wipK
totalRecords){ ZC9S0Z
int totalPage = 0; 6 IKi*}
]GXE2A_i;
if(totalRecords % everyPage == 0) NQ,2pM<*-
totalPage = totalRecords / everyPage; kV$VKag*A
else *[tLwl.
totalPage = totalRecords / everyPage + 1 ; yOyuMZo6
yS@xyW /
return totalPage; bOK0^$k
} zJG=9C?
B2,JfKk/
privatestaticboolean hasPrePage(int currentPage){ <ugy-vSv
return currentPage == 1 ? false : true; Zmy:Etqi
} d*Kg_He-
>C/O >g
privatestaticboolean hasNextPage(int currentPage, sF1j4 NC
;% 4N@Z
int totalPage){ DaqpveKa
return currentPage == totalPage || totalPage == 8C<%Y7)/
mxl"Y&l2<
0 ? false : true; yGlOs]>n
} R9InUX"k
UKf0cU
xU'% 6/G
} Fd >epvR
Ky)*6QOw
Il$Jj-)
nH|7XY9"
SHN'$f0Mb
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。 {GS$7n
-Ps kUl'
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 </|m^$v
Dh .<&ri
做法如下: ?Z"<&tsZ
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 {S5j;
cGS7s 8U
的信息,和一个结果集List: CF/8d6}Vf
java代码: =X=m_\=~@
tQcn%CK
"[\),7&03
/*Created on 2005-6-13*/ N3?hu}
package com.adt.bo; <{1=4PA
X&cm)o%5Fe
import java.util.List; 7kh(WtUz
MLt'tzgl
import org.flyware.util.page.Page; z#\YA]1
0Y9fK? (
/** R9O1#s^
* @author Joa .@3bz
*/ zfm#yDf
publicclass Result { 8U7X/L
@Jr@
fF}
private Page page; KU (g Zy
T:!Re*=JJ
private List content; v?`DP
lH%-#2]
/** QZamf
lk
* The default constructor e6uVUzP4
*/ z;6,,
public Result(){ L<_zQ
super(); ;@V1*7y
} eWTbHF
_/cL"Wf
/** FFpG>+*3
* The constructor using fields <^fvTb &*
* =w2_1F"
* @param page ZCz#B2Sf8
* @param content ;eT+Ly|{
*/ >j_N6B!
public Result(Page page, List content){ E 9v<VoNP`
this.page = page; jC_m0Iwc
this.content = content; g<PglRr"
} s|d"2w6t
Rxk0^d:sNi
/** raCgctYVq
* @return Returns the content. !FHm.E_>
*/ [ %6(1$Ih
publicList getContent(){ O7lFg;9c`
return content; K | '`w.
} Y[Eq;a132
Q$8&V}jVW
/** v]X*(e
* @return Returns the page. vfloha p
*/ YG
J)_y
public Page getPage(){ u?I 2|}#
return page; I@q(P>]X9
} xj;V
^vha4<'-qG
/** ki'CW4x
* @param content xA SH-9
* The content to set. ]'5 G/H5?;
*/ 6 U_P
public void setContent(List content){ r>cN,C
this.content = content; 3oBR
} aDda&RM
\h5!u1{L
/** ]_43U` [#
* @param page 1:22y:^j
* The page to set. xq<X:\O
*/ .JX9(#Uk
publicvoid setPage(Page page){ do:IkjU~
this.page = page; #eIFRNRb)
}
{[dY$
} y3OF+;E
#jM-XK
P7\?WN$p
f"SK3hI$p
CN:z
*g
2. 编写业务逻辑接口,并实现它(UserManager, L :Ldk
`k`P;(:
UserManagerImpl) uR6 `@F
java代码: `#"xgOSP>
iTVZo?lVo
u(i=-PN_<
/*Created on 2005-7-15*/ mM.YZUX
package com.adt.service; 8kT`5`}lB
8p]9A,Uq&
import net.sf.hibernate.HibernateException; hlmeT9v{
n x{MUN7
import org.flyware.util.page.Page; =YY 7V!
)3k?{1:
import com.adt.bo.Result; yxAy1P;dX
Q89fXi0Ivb
/** \,pObWm
* @author Joa H$.K
*/ " =6kH,
publicinterface UserManager { %77uc9}
l=ZD&uK
public Result listUser(Page page)throws mM:%-I\$
T^vhhfCUr
HibernateException; w[C*w\A\M
ERia5HnoD,
} Da8
|eN}
4AMe>s
voQJ!h1
#nw+U+qL
e;g7Ek3n
java代码: qw1W}+~g
L9-Jwy2(>
uehu\umt=
/*Created on 2005-7-15*/ ^`k;~4'd
package com.adt.service.impl; +abb[
&>&6OV]P'
import java.util.List; KA{&NFx
c g)>A
import net.sf.hibernate.HibernateException; KIp^|
k7>
e9HL)=YP
import org.flyware.util.page.Page; 1\~I "$}
import org.flyware.util.page.PageUtil; *@p"
%P D}VF/Y
import com.adt.bo.Result; Yxbg _RQm
import com.adt.dao.UserDAO; eh>
|m>JY
import com.adt.exception.ObjectNotFoundException; ?|98Y"w
import com.adt.service.UserManager; y0`;
br\X
OGIv".~s4
/** l i)6^f#
* @author Joa 1Iy1xiP
*/ IT{c:jo1{`
publicclass UserManagerImpl implements UserManager { @_?2iN?4Z
qajZ~oB{
private UserDAO userDAO; Q4_r) &np
W=3#oX.GsU
/** -gm5Eqi
* @param userDAO The userDAO to set. qZ'2M.;
*/ S3l^h4
publicvoid setUserDAO(UserDAO userDAO){ K4jHha
this.userDAO = userDAO; G%FZTA6a
} )obgEJ7Y`l
'(rD8 pc
/* (non-Javadoc) R~T}
* @see com.adt.service.UserManager#listUser 3>^]r jFw
=Y81h-
(org.flyware.util.page.Page) l)*(UZ"
*/ 7P<f(@0h$E
public Result listUser(Page page)throws "~0`4lo:Xo
sYBmL]Hr
HibernateException, ObjectNotFoundException { ) WbWp4
int totalRecords = userDAO.getUserCount(); J@2wPKh?Yp
if(totalRecords == 0) Rx&O}>"E>l
throw new ObjectNotFoundException NIVR;gm
Lc5zu7ncg
("userNotExist"); vQyY
%
page = PageUtil.createPage(page, totalRecords); %jy$4qAf%
List users = userDAO.getUserByPage(page); r'jUB^E
returnnew Result(page, users); l=p_
} @,GL&$Y:W
'fl< ac,.
} Qy0w'L/@
+T@BOYhgq
O*GF/ R8B
^n0;Q$\
" Q?~LB
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 /nQuM05*Z
ioD8-
询,接下来编写UserDAO的代码: :Q> e54]'&
3. UserDAO 和 UserDAOImpl: sWte&
java代码: =DJ:LmK
38p"lT
#| _VN %!
/*Created on 2005-7-15*/ M%`CzCL
u
package com.adt.dao; BP@tI|
x
C&IR*
import java.util.List; Zh;wQCDj
,M.}Q ak^
import org.flyware.util.page.Page; cyJ{AS+
(cOe*>L;
import net.sf.hibernate.HibernateException; wpM2{NTP
m%`YAD@2z
/** 'wk,t^)
* @author Joa B223W_0"o
*/ H]R/=OYBUh
publicinterface UserDAO extends BaseDAO { I{cH$jt<
iVn4eLK^v
publicList getUserByName(String name)throws cb /Q<i
B1)Eo2i#
HibernateException; {IJ;)<>&VE
}w$2,r
gA
publicint getUserCount()throws HibernateException; n8<?<-2
XeI2<=@%
publicList getUserByPage(Page page)throws VQHB}Y@^
w-pgtO|Us
HibernateException; #
-luE
tJ6@Ot
} d=xjLbsZ
HXa[0VOx
?Tc#[B
T06(Q[)
88osWo6rG
java代码: jG[Vp b
xUdGSr50
`xBoNQai
/*Created on 2005-7-15*/ tdH[e0x B
package com.adt.dao.impl; '|SO7}`;Q
c9-$^yno
import java.util.List; |X8?B=
T ?[28|
import org.flyware.util.page.Page; k\ #;
2xLtJR4L
import net.sf.hibernate.HibernateException; +-<G(^
import net.sf.hibernate.Query; e3;&
}#ZRi}f2VJ
import com.adt.dao.UserDAO; 3
,>M-F
#-'`Ybw
/** T/'z,,Y
* @author Joa X,v.1#[
*/ S/`#6
public class UserDAOImpl extends BaseDAOHibernateImpl MV" n{1B
.#QE*<T)]
implements UserDAO { $t;:"i>
s6|'s<x"j
/* (non-Javadoc) A] |w1nq
* @see com.adt.dao.UserDAO#getUserByName (fF8)4l
O^MI073Q>t
(java.lang.String) sQ}|Lu9hZ
*/ Ah2 {kK
publicList getUserByName(String name)throws PB@IPnB-
N\PdX$
HibernateException { b{<?E };%
String querySentence = "FROM user in class SI!A?34
#sw4)*v
com.adt.po.User WHERE user.name=:name"; 4QA~@pBX^{
Query query = getSession().createQuery LaQ7A,]
712nD ?>
(querySentence); r84^/+"T
query.setParameter("name", name); A08kwYxiW
return query.list(); r:bJU1P1$s
} p*b_"aF 1
}nlS&gew^
/* (non-Javadoc) VM%g QOo<
* @see com.adt.dao.UserDAO#getUserCount() +.!D>U$)}
*/ *S}@DoXS
publicint getUserCount()throws HibernateException { G!6b
)4L-
int count = 0; ]Ucw&B*@
String querySentence = "SELECT count(*) FROM a?-&O$UHf\
]CzK{-W
user in class com.adt.po.User"; *a Z1 4
Query query = getSession().createQuery Rn?JMM]
HEVjK$
(querySentence); w^0hVrws=,
count = ((Integer)query.iterate().next 1d< b\P0
<L]Gk]k_R
()).intValue(); TaRPMKk
return count; (,h2qP-;ud
} b=5w>*
Y!L-5|G
/* (non-Javadoc) &G"s!:
* @see com.adt.dao.UserDAO#getUserByPage G=zNZ
"SMJ:g",
(org.flyware.util.page.Page) yP{ 52%|+
*/ vxZ'-&;t
publicList getUserByPage(Page page)throws 32z4G =l
_{jC?rzb
HibernateException { F1.Xk1y%
String querySentence = "FROM user in class r
&.~
{
v Z9OJrF
com.adt.po.User"; #uU(G\^T
Query query = getSession().createQuery vW &G\L
@*y4uI6&
(querySentence); W4o8]&A
query.setFirstResult(page.getBeginIndex()) \x-2qlZ
.setMaxResults(page.getEveryPage()); |<u+Xi
~
return query.list(); RvAgv[8
} Rt?CE jy
s6~;)(r
} SZW_V6\t>
Po)U!5Tm
5[4wN(
)
_|u}^MLO
*<sc[..)
至此,一个完整的分页程序完成。前台的只需要调用 |N`0G.#
-W9DH^EL<
userManager.listUser(page)即可得到一个Page对象和结果集对象
b WNa6x
V| V9.
的综合体,而传入的参数page对象则可以由前台传入,如果用 oE+P=
!An?<Sv$
webwork,甚至可以直接在配置文件中指定。 Z4i))%or
3*<@PXpK&
下面给出一个webwork调用示例: ,cNe-KJk
java代码: |J!mM<*K
59zWB,y(P
)8C`EPe
/*Created on 2005-6-17*/ 08xo_Oysq
package com.adt.action.user; &9flNoNR9
nms[No?
import java.util.List; )vO"S
|~5cNm
import org.apache.commons.logging.Log; 71@eJQ
import org.apache.commons.logging.LogFactory; %nkP" Z#
import org.flyware.util.page.Page; MAYb.>X#>
B<I(t"s
import com.adt.bo.Result; lNxP
import com.adt.service.UserService; "Vq=
Ph
import com.opensymphony.xwork.Action; Bug.>ln1
6m$X7;x}
/** ~Y`ys[Z m
* @author Joa F{jxs/~
*/ o6A$)m5V
publicclass ListUser implementsAction{ MU$tX
Pp }Z"
privatestaticfinal Log logger = LogFactory.getLog 3g4=as4w
_S{TjGZ&
(ListUser.class); ei4LE
XQ16
bRu9*4t
private UserService userService; 8p 4[:M@
!M8_PC*a
private Page page; (W
h)Ov"
^5s7mls
privateList users; KD A8x W
B]tj0FB`-*
/* kFE9}0-
* (non-Javadoc) 8$~oiK%fw
* = vqJ0 !
* @see com.opensymphony.xwork.Action#execute() t|'%0 W
*/ iYB c4'X
publicString execute()throwsException{ CtMqE+j^
Result result = userService.listUser(page); [lML^CYQ
page = result.getPage(); 5,,'hAq_
users = result.getContent(); xwo*kFg
return SUCCESS; }~W/NP_F
} [[c0g6
SLEOcOAmD
/** Tl yyJ{~
* @return Returns the page. ynw(wSH=
*/ )&T 5/+
public Page getPage(){ *0" ojfVn
return page; Jd/d\P
} -6J <{1V
;-"!p
/** &iWTf K7
* @return Returns the users. <5%*"v
*/ CN(-Jd.b
publicList getUsers(){ 445JOP
return users; {Y5@SIyE
} ^f>c_[fR
tXA?[ S
/** &-FG}|*4M
* @param page MS#"TG/)
* The page to set. "7EK{6&jQ
*/ {HY3E}YJL
publicvoid setPage(Page page){ 6h5g!GQD
this.page = page; P !f{U;B
} Es#:0KH].v
vfn[&WN]
/** MR,I`9P e
* @param users _R(ZvsOZ
* The users to set. 9Vq
*/ 00D.Jn
publicvoid setUsers(List users){ 9h+Hd&=
this.users = users; Y$XzZ>VW
} >Z*b0j
OcMB)1uh\
/** /-!Fr:Ox>
* @param userService evZP*N~G
* The userService to set. xU%]G.k
*/ h/A\QW8Sd
publicvoid setUserService(UserService userService){ 7L/LlO/
this.userService = userService; /"="y'Wx
} Y?1T
XsvF
} bBML +0a
lIEZ=CEmY
$X;OK
>{(c\oMD
a ub$4n!C9
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, 3/usgw1
2HVqJib4Yn
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 n~
$S
`L$Av9X\
么只需要: ?uc]Wgw"s
java代码: "LDNkw'
Ep;?%o ,G
EP;ts
<?xml version="1.0"?> q1YNp`]0i8
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork yn+m,K/
X ]&`"Z]
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 2\.23
+ AjV0 #n
1.0.dtd"> A #SO}c
ubZuvWZ
<xwork> .$d:c61X
ER-Xd9R
<package name="user" extends="webwork- w<!&%
Xo(W\Pes
interceptors"> H/[(T%]o
:#sBNy
<!-- The default interceptor stack name i)cG
tMU10=d
--> 0Z((cI\J
<default-interceptor-ref
tculG|/
-KbO[b\V
name="myDefaultWebStack"/> }Dcpe M?
z,C>Rh9Id
<action name="listUser" 2y$DTMu
V^D1:9i
class="com.adt.action.user.ListUser"> c\P}ZQ
<param lr)MySsu#H
s#0m
name="page.everyPage">10</param> 26_PFHQu4
<result ?OO !M
e6jdSn
name="success">/user/user_list.jsp</result> RM2feWm
</action> `+KLE(]vyH
Z'^.H3YvL
</package> -jTK3&5
)086u8w )y
</xwork> w+%p4VkA<r
:/Y4I)'
+C`vO5\0
rA_r$X
uWXxK"J.
0j#$Swa
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 sh<JB`^$(?
g2r8J0v
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 |@>Zc5MY$
[.G~5%974
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 }2?-kj7
N~yGtnW
TlQ5'0&I
.W-=V zWX
kA 4kQ}q
我写的一个用于分页的类,用了泛型了,hoho "0"8Rp&V|
|TBKsx8
java代码: T:j!a{_|
DGAg#jh
cm7>%g(oQo
package com.intokr.util; [+$o`0q;N?
!g-19at
import java.util.List; kIUb`b>B
j]_"MMwk$<
/** (hX}O>
* 用于分页的类<br> xSHeP`P^X
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 1G+?/w
* 4mzWNr>fb
* @version 0.01 jG3i
)ALx
* @author cheng FmRa]31W
*/ Z)zmT%t
public class Paginator<E> { [P_1a`b
privateint count = 0; // 总记录数 m)9qO7P
privateint p = 1; // 页编号 #G ZGk?
privateint num = 20; // 每页的记录数 &ExYul
privateList<E> results = null; // 结果 4 p(KdYc
MoP0qNk
/** *m sW4|=^2
* 结果总数 0zAj.iG
*/ \YBY"J
publicint getCount(){ =' cr@[~i
return count; Et+N4w
} v2Bks2
|f0KIb}d
publicvoid setCount(int count){ ?qQRA|n*
this.count = count; xe6 2gaT
} [Hww3+~+
|3MqAvPJ
/** 8Mq]
V
v
* 本结果所在的页码,从1开始 JtU/%s
* z<jWy$Ta;
* @return Returns the pageNo. _6
~/`_(KP
*/ 5xHl6T+
publicint getP(){ f&Bu_r
return p; p'
FYK|
} g9;}?h
<5~} !N X`
/** zRJopcE<
* if(p<=0) p=1 4+`<' t]Q
* x=bAR%i~
* @param p xF_ Y7rw1w
*/ '+|{4-V
publicvoid setP(int p){ #{l+I(M
if(p <= 0) l
49)Cv/
p = 1; ,bCPO`45
this.p = p; ?zN v7Bj
} XH0R:+s
oM$EQd`7
/** /9WR>NUAO
* 每页记录数量 ^=wG#!#V"1
*/ x1$tS#lS
publicint getNum(){ )=X8kuB~
return num; 1HBch]J
} k"V3FXC)
ue$\i =jw
/** Vcl"qz@Fj
* if(num<1) num=1 _'dsEF
*/ V2'(}k
publicvoid setNum(int num){ >=i47-H
if(num < 1) ?PSm)
~Oa
num = 1; >ea<6&!Ee
this.num = num; d;(L@9HHD
} Tfgx>2
q0w5ADd
/** QKbX^C
* 获得总页数 kkFE9:[-c&
*/ JMOQDo
publicint getPageNum(){ ^gh/$my;
return(count - 1) / num + 1; SA{A E9y
} >&aFSL,f
GOa](oD}
/** #=b_!~:%
* 获得本页的开始编号,为 (p-1)*num+1 RWXj)H)w
*/ @=b0>^\m
publicint getStart(){ JHc|.2Oe
return(p - 1) * num + 1; >RBq&'f
} \y:
0+s/
{`KgyCW:
/** PQXyu1
* @return Returns the results. lyIstfRh15
*/ 9.lSF
publicList<E> getResults(){ brNe13d3~"
return results; naXo <B
} :4<+)r26
M`KrB5a+6
public void setResults(List<E> results){ [lQp4xgxi
this.results = results; "(/|[7D)
} ~DPg):cZ
q!""pr<n
public String toString(){ -deY,%
StringBuilder buff = new StringBuilder _w^p~To^
iyu%o9_0
(); ]BP/KCjAI<
buff.append("{"); GfJm&'U&
buff.append("count:").append(count); &EXql']
buff.append(",p:").append(p); ;#3!ZB:}
buff.append(",nump:").append(num); X+P&
up06
buff.append(",results:").append `\q4z-<-
K,|Gtaa~
(results); 7SXi#{
buff.append("}"); EZIMp8^
return buff.toString(); /I$g .f/#
} QCa$<~c
!F;W#Gc
} A7+eWg{
N~\1yQT
zL3~,z/o