Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 N=T}
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Z,O-P9jC
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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 %Ny1H/@Q1+
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 c~OPH
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。 52Dgul
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分页支持类: #Hu##x|
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java代码: ;1nXJ{jKw
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package com.javaeye.common.util; rLmc(-q
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import java.util.List; ]>k8v6*=
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publicclass PaginationSupport { #<sK3 PT
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publicfinalstaticint PAGESIZE = 30; @.}Y'`9L
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privateint pageSize = PAGESIZE; _zzNF93Bn
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privateList items; #=ij</
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privateint totalCount; `Eu,SvkF w
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privateint[] indexes = newint[0]; cT/mi":8{
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privateint startIndex = 0; 2DJg__("
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public PaginationSupport(List items, int d=uGB"
C|w<mryx
totalCount){ H`URJ8k$Q
setPageSize(PAGESIZE); 4/mz>eK"
setTotalCount(totalCount); cwtlOg
setItems(items); whP5u/857
setStartIndex(0); kdV9F
} CRNi*u
uW#s;1H.)
public PaginationSupport(List items, int hm0A%Js
I} +up,B]o
totalCount, int startIndex){ um_J%v6ER
setPageSize(PAGESIZE); y3QS!3I
setTotalCount(totalCount); *f>\X[wN
setItems(items); Jq? zr]"A
setStartIndex(startIndex); a'Zw^g
} V,'_BUl+x
1n7'\esC*
public PaginationSupport(List items, int $G }9iV7
h# Z,ud_
totalCount, int pageSize, int startIndex){ *vIP\NL?H
setPageSize(pageSize); %N(>B_t\
setTotalCount(totalCount); $Zw+"AA
setItems(items); Jmg9|g!f
setStartIndex(startIndex); f5un7,m
} |_7k*:#q:
.7 LQ l?
publicList getItems(){ :i0;jWcb
return items; 3^fwDt}
} L+
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publicvoid setItems(List items){ &HAu;u@
this.items = items; d8+@K&z|
} dKU:\y
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publicint getPageSize(){ "X;5*
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return pageSize; `#8k Jt
} %xQ'i4`
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publicvoid setPageSize(int pageSize){ YX)Rs
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this.pageSize = pageSize; r@vt.t0#
} XOI"BLd
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publicint getTotalCount(){ '@M"#`#0
return totalCount; q+p}U}L=
k
} Gr/}&+S
2QAP$f0Ln
publicvoid setTotalCount(int totalCount){ #-+Q]}fB4
if(totalCount > 0){ Y3(MKq
this.totalCount = totalCount; w4}Q6_0v
int count = totalCount / K{`R`SXD
lA1
pageSize; y06**f)
if(totalCount % pageSize > 0) Tbv w?3
count++; ~tRGw^<9
indexes = newint[count]; Is<XMR|{
for(int i = 0; i < count; i++){ j%w^8}U>G
indexes = pageSize * hAc|a9 o
LW.j)wB]
i; \)o.Y
zAo@
} X/vyb^:U
}else{ $\/^O94-l
this.totalCount = 0; JN` $Fq+
} Yo'Y-h#
} l:JVt`A4?
@H4]Gp ]
publicint[] getIndexes(){ *)
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return indexes; v@q&B|0
} .|hsn6i/-
|W=-/~X
publicvoid setIndexes(int[] indexes){ -vT{D$&1
this.indexes = indexes; \-[bU6\A\
} }79jyS-e
2\z|/
Q
publicint getStartIndex(){ dW!El^w}
return startIndex; "M[&4'OM
} /VufL+q1
*>mjUT}cP
publicvoid setStartIndex(int startIndex){ "-X8
if(totalCount <= 0) s2|.LmC3|B
this.startIndex = 0; /^k%sG@?
elseif(startIndex >= totalCount) A s}L=2
this.startIndex = indexes 1;S?9N_B
'v
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[indexes.length - 1]; & /T}
elseif(startIndex < 0) m;>G]Sbe
this.startIndex = 0; 3BD&;.<r
else{ [r3sk24
this.startIndex = indexes Eri007? D
$%"hhju
[startIndex / pageSize]; N"G\H<n
} r63l(
} JA9NTu(
jXALL8[c
publicint getNextIndex(){ (GpP=lSSeY
int nextIndex = getStartIndex() + [M%?[E}>
&oHr]=xA
pageSize; +>*=~R
if(nextIndex >= totalCount) oQmXKV+[v
return getStartIndex(); r nr-wUW@
else mTWd+mx
return nextIndex; )8#-IXxp
} S (xs;tZ
'Rsr*gX#
publicint getPreviousIndex(){ _D?/$D7u#%
int previousIndex = getStartIndex() - fjy\Q
]u$tKC
pageSize; W'"?5} (
if(previousIndex < 0) )uo".n|n~B
return0; 3%GsTq2o
else $|J+
return previousIndex; <\Y(+?+uZ
} 41Q)w=hoN
hHVAN3e
} S,Q^M
)$
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.$W}
@sZ7Ka
抽象业务类 X@tA+
java代码: I(7iD. ^:
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/** ftPhE)i
* Created on 2005-7-12 ^lZ7% 6
*/ pKj:)6t"
package com.javaeye.common.business; ip}%Y6Wj
h?OSmzRLd
import java.io.Serializable; biS[GyQ
import java.util.List; /<$|tp\Rc
_RxnB?
import org.hibernate.Criteria; fS|e{!iI"
import org.hibernate.HibernateException; dJnKa]X
import org.hibernate.Session; ~aQR_S
import org.hibernate.criterion.DetachedCriteria; C6a-
import org.hibernate.criterion.Projections; 85[
7lO)[
import ~Y*.cGA
Ank_;jo
org.springframework.orm.hibernate3.HibernateCallback; dz/fSA
import Cu24xP`
: fYfXm
org.springframework.orm.hibernate3.support.HibernateDaoS }wvR s5;o
Gsy>"T{CY
upport; |IzL4>m:;
L/WRVc6
import com.javaeye.common.util.PaginationSupport; iM:-750n/
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public abstract class AbstractManager extends ps,Kj3^T<
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HibernateDaoSupport { mrG?5.7W
w ~crj$UM
privateboolean cacheQueries = false; 8?kB+}@6X
R_GA`U\ {
privateString queryCacheRegion; -X%twy=
U"Bge\6x=
publicvoid setCacheQueries(boolean 8,vP']4r%
fSVM[
cacheQueries){ hslT49m>
this.cacheQueries = cacheQueries; lV4TFt,
} ELMz~vp
E)jd>"
publicvoid setQueryCacheRegion(String Bd=K40Z:
(,+#H]L
queryCacheRegion){ md18q:AG)
this.queryCacheRegion = B= E/|J</
4Y1^ U{A+
queryCacheRegion; VbJE zl
} {6qxg _{
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publicvoid save(finalObject entity){ 9 4lt?|3=
getHibernateTemplate().save(entity); (yd(ZY
} 7zE1>.
m
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publicvoid persist(finalObject entity){ 1'TS!/ll];
getHibernateTemplate().save(entity); tq'hiS(b
} s%Ph
jR\! 2!
publicvoid update(finalObject entity){ 40].:9VG
getHibernateTemplate().update(entity); udr|6EjD.
} s/11TgJ
w?nSQBz$
publicvoid delete(finalObject entity){ w;AbJCv2
getHibernateTemplate().delete(entity); G^K;+& T
} 4K`b?{){+a
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publicObject load(finalClass entity, [`tNa Vg
CA&VnO{r
finalSerializable id){ $/#[,1
return getHibernateTemplate().load ;ud"1wH
b|kL*{;
(entity, id); "o u{bKe
} z+wegF
2MYez>D
publicObject get(finalClass entity, lAC"7 Z?F
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finalSerializable id){
tIod=a)
return getHibernateTemplate().get Zj ^e8u=T
\j wxW6>
(entity, id); p*YV*Arv
} DyZ6&*s$
0
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_/
publicList findAll(finalClass entity){ 9X33{
return getHibernateTemplate().find("from Tl-%;X<X
UMD\n<+cG,
" + entity.getName()); x00'wY|
} wnXU=
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publicList findByNamedQuery(finalString XA. 1Y)
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namedQuery){ \fI05GZ
return getHibernateTemplate *L*{FnsV
ze5#6Vzd&
().findByNamedQuery(namedQuery); wCv9VvF`
} u:W/6QS
152s<lu1Z
publicList findByNamedQuery(finalString query, lm&^`Bn)
4u41M,nJQd
finalObject parameter){ I|;zGmg#k
return getHibernateTemplate F,pKt.x
la 0:jO5
().findByNamedQuery(query, parameter); IFa~`Gf [
} xy&*s\=:
wzoT!-_X
publicList findByNamedQuery(finalString query, PX/^*
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finalObject[] parameters){ pg_H' 0R
return getHibernateTemplate ^AOJ^@H^>
B^R44j]3"
().findByNamedQuery(query, parameters); ,v=pp;
} QpoC-4F
x6Gl|e[jv
publicList find(finalString query){ i$6a0'@U
return getHibernateTemplate().find THK^u+~LM
w&VDe(:~
(query); /!p}H'jl
} f;,*P,K
0blbf@XA
publicList find(finalString query, finalObject [fvjvN`
r5(efTgAd+
parameter){ s+&0Z3+
return getHibernateTemplate().find sP%b?6
TA:#K
(query, parameter); -3b_}by
} j:2F97
>/%XP_q%`e
public PaginationSupport findPageByCriteria }rs>B,=*k
i;|I;5tC
(final DetachedCriteria detachedCriteria){ a gL@A
return findPageByCriteria \ZE=WvnhZ
>$r o\/
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Qr6PkHU
} ZUz7h^3@
C,LosAd
public PaginationSupport findPageByCriteria NB.'>Sar
I};*O6D`
(final DetachedCriteria detachedCriteria, finalint 7;Q4k"h
fuF{8-ua
startIndex){ (#z6w#CU(
return findPageByCriteria ^7;s4q
$2}%3{<j
(detachedCriteria, PaginationSupport.PAGESIZE, S>j.i
R)isWw4
startIndex); 6P,uy;PJ
} N:+d=G`x
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public PaginationSupport findPageByCriteria JZ:yPvJ
GWWaH+F[h
(final DetachedCriteria detachedCriteria, finalint H(M{hfa|
m"'`$ /_
pageSize, +~y>22Zfg
finalint startIndex){ ,LmP >Q.
return(PaginationSupport) ~0?B
6mIK[Qnp
getHibernateTemplate().execute(new HibernateCallback(){ PqF&[M<)
publicObject doInHibernate /J&DYxl":
[9MbNJt 8~
(Session session)throws HibernateException { 3Z#WAhfS:
Criteria criteria = ?*7Mn`
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detachedCriteria.getExecutableCriteria(session); WA:r4V
int totalCount = KU]o=\ak%
P46Q3EE
((Integer) criteria.setProjection(Projections.rowCount ?gjx7TQ?
@A*>lUo
()).uniqueResult()).intValue(); '4Qsl~[Eh
criteria.setProjection AR$SQ_4
)%n$_N n
(null); MQ0rln?
List items = difX7)\
_ F|}=^Z`
criteria.setFirstResult(startIndex).setMaxResults g+<[1;[-
r}D#(G$
(pageSize).list(); Jo~fri([%Q
PaginationSupport ps = 0!$y]Gr
3 5L0CM
new PaginationSupport(items, totalCount, pageSize, iy]?j$B$
]H\tz@
&
startIndex); uaU2D-ft"
return ps; >V]9<*c
} ,j.bdlI#
}, true); jcBZ#|B7;
} n5IQKYrg
/m 7~-~$V
public List findAllByCriteria(final Z{yH:{Vk
0\@oqw]6hv
DetachedCriteria detachedCriteria){ ijzwct#.
return(List) getHibernateTemplate gxAy{
t
b`=g#B|
().execute(new HibernateCallback(){ 6qT-
publicObject doInHibernate rK:cUW0]X
y=EVpd
(Session session)throws HibernateException { UEfY'%x
Criteria criteria = X|ZAC!J5>
=_ b/g
detachedCriteria.getExecutableCriteria(session);
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return criteria.list(); MOnTp8
} mo(>SnS<
}, true); K'
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} _5x]BH6f
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public int getCountByCriteria(final p?4[nS-,
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DetachedCriteria detachedCriteria){ +"=ydF.9
Integer count = (Integer) A=p'`]Yld
\4C[<Gbx$(
getHibernateTemplate().execute(new HibernateCallback(){ u|.7w2
publicObject doInHibernate u*,>$(-u
)58~2vR
(Session session)throws HibernateException { CA5`uh
Criteria criteria = `+>K)5hrR
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detachedCriteria.getExecutableCriteria(session); :Q@/F;Z?
return uLPBl~Y
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criteria.setProjection(Projections.rowCount mw;4/
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0(:SEiz6s
()).uniqueResult(); FOMJRq
} vZ.<OD4
}, true); < *;GJ{
return count.intValue(); jvL!pEC!
} M6Np!0G
} e"NP]_vh,
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h0g?=hJq
/S1/ ZI
5s`r&2 w
用户在web层构造查询条件detachedCriteria,和可选的 )7o?}"I
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startIndex,调用业务bean的相应findByCriteria方法,返回一个
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7C,giCYU
PaginationSupport的实例ps。 [A"=!e$<
GdVF;
ps.getItems()得到已分页好的结果集 jY]51B
ps.getIndexes()得到分页索引的数组 `8RKpZv&
ps.getTotalCount()得到总结果数 U,;796h
ps.getStartIndex()当前分页索引 }f?[m&<
ps.getNextIndex()下一页索引 E]GbLU;TH
ps.getPreviousIndex()上一页索引 A~<!@`NjB
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 x-X~'p'f
BI %XF
9{
,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 QeuM',6R
=|ODa/2p
一下代码重构了。 [3nWxFz$R
{B4qeG5
我把原本我的做法也提供出来供大家讨论吧: g3>>gu#0DC
hd~#I<8;2
首先,为了实现分页查询,我封装了一个Page类: vO~Tx
java代码: 1PUZB`"3
,qv\Y]
L~Peerby
/*Created on 2005-4-14*/ /w(g:e
package org.flyware.util.page; {tY1$}R
kmc"`Ogotw
/** %<(d%&~
* @author Joa |l+5E
* 8B?U\cfa^
*/ ~~-VScG&
publicclass Page { ftR& 5!Wm
83t/\x,Q
/** imply if the page has previous page */ cGgfCF^`
privateboolean hasPrePage; c$7~EP
7H< IO`
/** imply if the page has next page */ *URT-+'
privateboolean hasNextPage; tzIP4CR~F&
p'2IlQ\
/** the number of every page */ 4^bt~{}
privateint everyPage; E1OrL.A6
mY4pvpZw8
/** the total page number */ M>p<1`t-&
privateint totalPage; It&CM,=t
TPk?MeVy%W
/** the number of current page */ Wtcib-
privateint currentPage; !W@mW
5J|
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/** the begin index of the records by the current Ue
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rpm \!O
query */ "IT7.!=@9
privateint beginIndex; kex V~Q
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/** The default constructor */ 7KhS{w6
public Page(){ rMbq_5}
0r1GGEW`s
} 9 $$uk'}w!
\+O.vRc"M
/** construct the page by everyPage Z6i~Dy3
* @param everyPage PD.$a-t
* */ S,AxrQc
public Page(int everyPage){ \j62"
this.everyPage = everyPage; "N6HX*
} "j,vlG
J~]@#=,v
/** The whole constructor */ ?1JY6v]h4
public Page(boolean hasPrePage, boolean hasNextPage, ^?+[yvq
P{6$".kIY
Rq5'=L
int everyPage, int totalPage, s~A-qG>
int currentPage, int beginIndex){ Lxv 4w
this.hasPrePage = hasPrePage; U\?D;ABQ%
this.hasNextPage = hasNextPage; 49&i];:%7%
this.everyPage = everyPage; C:t>u..
this.totalPage = totalPage; #[{{&sN
this.currentPage = currentPage; EpMxq7*
this.beginIndex = beginIndex; >U{iof<
} /)Cfm1$ic
VbvP!<8
/** y2#>a8SRS
* @return nJN-U+)u
* Returns the beginIndex. i3N{Dt
*/ 3u/JcU-<
publicint getBeginIndex(){ WT<}3(S'?
return beginIndex; v-3VzAd=*&
} K_)~&Cu*'
qsep9z.
/** VRQ`-#
* @param beginIndex c.IUqin
* The beginIndex to set. znsQ/[
*/ w8 :[w
publicvoid setBeginIndex(int beginIndex){ %%s)D4sW
this.beginIndex = beginIndex; 8O'bCBhv
} S9Yzvq!(
3d6z_Yd:
/** ITw *m3
* @return H@1'El\9
* Returns the currentPage. $kTm"I
*/ x:MwM?
publicint getCurrentPage(){ s"=TM$Vb
return currentPage; 8c)GUx
} nD
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t[`LG)
/** Gg'!(]v
* @param currentPage .T9$O]:o
* The currentPage to set. m1pA]}Y/5o
*/ @-dGZ5
publicvoid setCurrentPage(int currentPage){ 9m)$^U>oz
this.currentPage = currentPage; Hp=BnN
} -a)1L'R
A
r]*?:4y[
/** >fXtu:C-!J
* @return qKfUm:7Q_
* Returns the everyPage. eavn.I8J
*/ Ra|P5
publicint getEveryPage(){ l!x+K&
return everyPage; zX_F+"]THt
} U*=E(l
SPb+H19;
/** 0* F` h
* @param everyPage
^^"zjl*^
* The everyPage to set. ~-A"j\gi"
*/ UF!qp
publicvoid setEveryPage(int everyPage){ d*d:-f~q
this.everyPage = everyPage; 3O2G+G2
} r89AX{:
/&Oo)OB;
/** l|WFS
* @return i|1*bZ6'
* Returns the hasNextPage. %Z_O\zRqy)
*/ U_*,XLU
publicboolean getHasNextPage(){ n>, :*5"G
return hasNextPage; 'M~`IN`
} *ai~!TR
$\NqD:fgb
/** e' l9
* @param hasNextPage 7(+4^
* The hasNextPage to set. 'Eur[~k
*/ ev;&n@k_I
publicvoid setHasNextPage(boolean hasNextPage){ )\Q(=:
this.hasNextPage = hasNextPage; e
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} Sxq@W8W
Qf( A
/** }?,?2U,8:
* @return Q^f{H.
* Returns the hasPrePage. 4}m9,
*/ $~b6H]"9
publicboolean getHasPrePage(){ i`gM> q&
return hasPrePage; <4Gy~?
} Nf )YG!
v=@y7P1
/** r5~W/eE
* @param hasPrePage @bA5uY!
* The hasPrePage to set. $@'BB=i
*/ X3}eq|r9
publicvoid setHasPrePage(boolean hasPrePage){ cOV9g)7^O
this.hasPrePage = hasPrePage; M)oKtiav*
} 'd$RNqe
ts,r,{
/** */M`KPW
* @return Returns the totalPage. B%6cgm,
* Kz42AC
*/ z='%NZY
publicint getTotalPage(){ 0beP7}$
return totalPage; b~vV++ou_
} Jo\MDyb]
Z|E9}Il]
/** N 5*Qnb8
* @param totalPage 4tCM2it%
* The totalPage to set. Vr},+Rj
*/ I*N"_uKU
publicvoid setTotalPage(int totalPage){ /3aW 0/^o
this.totalPage = totalPage; &qS%~h%2
} u$R5Q{H_
5c]:/9&
} 1@p,
$b|LZE\bU.
+ kMj|()>\
:u,.(INB
D:Q#%wJ
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 8Ij<t{Lps
QZ&(e2z
个PageUtil,负责对Page对象进行构造: [cnuK
java代码: o>8~rtl
;<garDf
R278 ^E
/*Created on 2005-4-14*/ N-upNuv
package org.flyware.util.page; [<53_2]~
'*y(F*7+
import org.apache.commons.logging.Log; j_2g*lQ7a
import org.apache.commons.logging.LogFactory; T MMKRC1<
!=:>y WQ
/** \B4H0f
* @author Joa id:,\iJ
* yo#r^iAr
*/ ] x)>q
publicclass PageUtil { lV^#[%
ndLEIqOY
privatestaticfinal Log logger = LogFactory.getLog ,RR{Y-
A6=Z2i0w>X
(PageUtil.class); |,,#DSe
gttsxOgktH
/** h,Hr0^?
* Use the origin page to create a new page :o!Kz`J
* @param page X0
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* @param totalRecords
/#Pm'i>B
* @return u"qu!EY2
*/ "j_iq"J
publicstatic Page createPage(Page page, int "a[;{s{{.
qI uo8o}
totalRecords){ ,<L4tp+y0
return createPage(page.getEveryPage(), )<V!lsUx'-
&Gh,ROo4
page.getCurrentPage(), totalRecords); mj'~-$5T
} ltuV2.$
Vx<{cHQQ
/** [`GSc6j
* the basic page utils not including exception PFX,X
oUnb-,8n
handler 9$$ Ijf
* @param everyPage F)cCaE;
* @param currentPage
Hy3J2p9.
* @param totalRecords i$] :Y`3h
* @return page @HbRfD/!
*/ xK6`|/e
publicstatic Page createPage(int everyPage, int clU ?bF~e1
hhPQ.{]>
currentPage, int totalRecords){ e^eJ!~0
everyPage = getEveryPage(everyPage); t}R!i-D|HB
currentPage = getCurrentPage(currentPage); 8j>V?'Szk
int beginIndex = getBeginIndex(everyPage, S} UYkns*
1!^BcrG.
currentPage);
#tKks:eL
int totalPage = getTotalPage(everyPage, :'bZ:J>f
nqH[
y0
totalRecords); zY\u"
'4
boolean hasNextPage = hasNextPage(currentPage, 2B$dT=G
}SWfP5D@
totalPage); 9!jF$
boolean hasPrePage = hasPrePage(currentPage); I+
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d\#yWY
returnnew Page(hasPrePage, hasNextPage, AVjRhe
everyPage, totalPage, ZOfv\(iJ;
currentPage, fC'u-m?!Q'
sX6\AYF1M
beginIndex); y<6Sl6l*
} ^4`x:6m
p'LLzc##
privatestaticint getEveryPage(int everyPage){ g
sm%4>sc
return everyPage == 0 ? 10 : everyPage; R8[VD iM6E
} &C
MBTY#u
= "]r{
privatestaticint getCurrentPage(int currentPage){ P\Qvj7_
return currentPage == 0 ? 1 : currentPage; YMu#<ZG
} "&SE!3*m`I
vx?KenO}
privatestaticint getBeginIndex(int everyPage, int AT
I=&O`
>e!J(4.-
currentPage){ dE8f?L'
return(currentPage - 1) * everyPage; 75H!i$(*+
} R^`}DlHX
#"6l+}
privatestaticint getTotalPage(int everyPage, int :i>LESJq
#tZ!D^GQHq
totalRecords){ 6%p6BK6
int totalPage = 0; CL2zZk{u_
(QIU 3EN
if(totalRecords % everyPage == 0) 4OM
]8I!
totalPage = totalRecords / everyPage; 10zM8<bl
else x3Cn:F
totalPage = totalRecords / everyPage + 1 ; a"P &
9c
Fw[1Aa#
return totalPage; hvTc( 0;mB
} <9>L^GgXA
^e^-1s
S
privatestaticboolean hasPrePage(int currentPage){ agfDx^,
return currentPage == 1 ? false : true; L$c 1<7LU
} 5(#z)T
8-+# !]
privatestaticboolean hasNextPage(int currentPage, ]uhG&:
}
$xW9))
int totalPage){ GjEV]hqR
return currentPage == totalPage || totalPage == C4E}.``Hm
aT2%Az@j
0 ? false : true; xb[yy}>"L
} ?W ^`Fa)]o
M#2<|VUW,
'exR;q\
} < k(n%
o]p$
w[5
o!h::j0,~
w$$pTk|&n
"d/54PKWx
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。 T#rUbi>""
&O+S[~
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 |b@`ykD
tPiC?=4R
做法如下: v89tV9O)
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 "xC$Ko _
w\
'5lk,"
的信息,和一个结果集List: M GC=L .
java代码: 9Q(Lnu
zz3{+1w]
vB7]L9=@"
/*Created on 2005-6-13*/ }c8e t'HYf
package com.adt.bo; %m lH
|(x%J[n0+
import java.util.List; SgQmR#5
{>9<H]cSP
import org.flyware.util.page.Page; w,6gnO
S8;c0}-
/** qtVgjT2#H
* @author Joa 2|!jst
*/ -;Mh|!yg
publicclass Result { D_F1<q
Xl$r720ZJr
private Page page; E\4ZUGy0
uuHs)
private List content;
*W |
Q.4+"JoG
/** {3os9r,
* The default constructor $!'Vn)Z7
*/ G|&$/]~
public Result(){ %j0c|u
super(); %j2 :W\g:
} Y]&2E/oc
\o,et9zDJ3
/** R90chl
* The constructor using fields
CU\r
I
* !x-9A
* @param page @(/$;I,
* @param content h{]0
H'g
*/ qoQ,3&<
public Result(Page page, List content){ wMm+E "}W
this.page = page; &_QD1 TT
this.content = content; sAX4giaLD
} ]*DIn1C^
&z\?A2Mw%
/** $\oe}`#o
* @return Returns the content. &xj,.;
*/ 5 a&a-(
publicList getContent(){ Jk<b#SZ[b
return content; v>hc\H1P
} hsws7sH
nm|"9|/
/** IQ#Kod;)
* @return Returns the page. s?sr0HZ
*/ ayf;'1
public Page getPage(){ M1DV 9~S
return page; 4GJx1O0Ol
} ^7kYG7/
D#ED?Lqf
/** PVq y\i
* @param content pkIJbI{aS
* The content to set. (:#4{C
*/ &fxyY(
public void setContent(List content){ sBN4:8
this.content = content; B`%%,SLJ
} L@ N\8mf
Qmv8T
^+
/** I7#+B1t
* @param page A{hST~s
* The page to set. (a|Wq{`[
*/ Gnqun%
publicvoid setPage(Page page){ (j)>npOd9
this.page = page; P^/e!%UgC
} w\a9A#v,
} FbPoyh
t-hN4WKH_A
!\Q/~p'jS
_l]rt
W<H^V"^
2. 编写业务逻辑接口,并实现它(UserManager,
ra\2BS)X
&2Cu"O'.i
UserManagerImpl) 0j-;4>p
java代码: 4mWT"T-8
q'[yYPDX5x
K@=_&A!
/*Created on 2005-7-15*/ -QydUr/(o
package com.adt.service; \xtmd[7lb<
j98>Jr\
import net.sf.hibernate.HibernateException; u $T'#p1
/#4BUfY
f
import org.flyware.util.page.Page; /I#SP/M&l
%$(*.o!+8
import com.adt.bo.Result; }15ooe%
0'y3iar
/** c:`&QDF
* @author Joa Y4/ !b
*/ ?37Kc,o
publicinterface UserManager { r`=!4vY2
!7kca#,X
public Result listUser(Page page)throws N5GQ2V
-}<W|r
HibernateException; d,).O
Ll6|Wh X
} e0u*\b
0 Pa\:^/6
`Df)wNN1
~%:23mIk
DadlCEZv
java代码: !~aDmY2
WAbt8{$D
>/F,Z%!&q
/*Created on 2005-7-15*/ }q@Jh*
package com.adt.service.impl; ,`< [ej
K1Wiiw
import java.util.List; >sE{c>R%
)0Lv-Gs
import net.sf.hibernate.HibernateException; oBTRO0.s+
fDY#&EO: %
import org.flyware.util.page.Page; h3Z0NJ=xM
import org.flyware.util.page.PageUtil; Ke+#ww
KGb3n;]
import com.adt.bo.Result; |Gh~Zup
import com.adt.dao.UserDAO; U ()36
import com.adt.exception.ObjectNotFoundException; 8U>f/dxLOO
import com.adt.service.UserManager; H<YS2Ed
O>`DR0
/** 8CKI9
* @author Joa lGr(GHn
*/ Rm!Iv&{
publicclass UserManagerImpl implements UserManager { @RF!p
x+7jJ=F
private UserDAO userDAO; gG.b=DvzY
3 aG?^z
/** !j?2HlIK+
* @param userDAO The userDAO to set. _/5mgn<GK
*/ H{CG/+x
publicvoid setUserDAO(UserDAO userDAO){ aYQIe7J90J
this.userDAO = userDAO; qTL]
} miZ&9m
f=Rx8I
/* (non-Javadoc) Mrlv(1PQT
* @see com.adt.service.UserManager#listUser 1Lb+
&
;u0MY
(org.flyware.util.page.Page) $k|k 5cP8x
*/ dRXF5Ox5K}
public Result listUser(Page page)throws 1x#Z}XG
hqVFb.6[
HibernateException, ObjectNotFoundException { H`;q@
int totalRecords = userDAO.getUserCount(); Fh4kd>1D
if(totalRecords == 0) -HU5E>xG
throw new ObjectNotFoundException P p[?E.]P
v(/T<^{cuk
("userNotExist"); Zi fAn
page = PageUtil.createPage(page, totalRecords); TPrqb
List users = userDAO.getUserByPage(page); @<O
Bt d
returnnew Result(page, users); u<l[S
} Wo@0yF@
o'Byuct
} UmSy p\i
U1t7XZ3e
g9`z]qGWS:
4~3 N;]X
lXS.,#lp
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 W7lR54%|
/MB3w m
询,接下来编写UserDAO的代码: O!(M:.
3. UserDAO 和 UserDAOImpl: Ph'P<h:V
java代码: kw>W5tNpf:
~4\J}Kn
|T}Q~
/*Created on 2005-7-15*/ Oozt&* F
package com.adt.dao; YULI
y-W
CD'.bFO^+T
import java.util.List; *1fq :--
#%xzy@`
import org.flyware.util.page.Page; EencMi7J
c|%.B2
import net.sf.hibernate.HibernateException; s=&&gC1
Pvq74?an`
/** K"O+`2$
* @author Joa OsMU>v }m
*/ \ s8j*
publicinterface UserDAO extends BaseDAO { ua%$r[
SM2QF
publicList getUserByName(String name)throws P\B ]><!ep
/d*0+m8
HibernateException; F/FUKXxx
I5l5fx
publicint getUserCount()throws HibernateException; 'a`cK;X9F
YQWGv,47\
publicList getUserByPage(Page page)throws )A}u)PH4O
dC$z q~q
HibernateException; "#d>3M_
RCSG.*% %I
} 0>?%{Xy
d|!FI/
2 HNKq<
(,wIbwa
^u@"L
java代码: {2EIvKu3:
)aov]Ns
bhqBFiuhH
/*Created on 2005-7-15*/ |kPjjVGF{
package com.adt.dao.impl; '%.:97
N^\<y7x
import java.util.List; ,Q8[Ur?G
|'B-^? ;
import org.flyware.util.page.Page; xx`xDD
y3^<rff3Gc
import net.sf.hibernate.HibernateException; mhZ{}~
import net.sf.hibernate.Query; 9?5'>WO
b*w@kLLN
import com.adt.dao.UserDAO; $9!2c /
+ML4.$lc^
/** }w{6Ua
* @author Joa [&e|:1
*/ F<K;tt
public class UserDAOImpl extends BaseDAOHibernateImpl cI~uI'
z']TRjDbT
implements UserDAO { 4PtRTb0<i3
0x&-/qce6W
/* (non-Javadoc) 5G!0Yy['
* @see com.adt.dao.UserDAO#getUserByName >/@wht4- j
Ah5`Cnv
(java.lang.String) J?]wA1
*/ I!FIV^}Z(
publicList getUserByName(String name)throws 3K2B7loD)~
y:t@X~
HibernateException { F xek#
String querySentence = "FROM user in class )k)HQcfjD
dwd5P7
com.adt.po.User WHERE user.name=:name"; <$6r1y*G
Query query = getSession().createQuery {kCCpU
a_jw4"Sb
(querySentence); .dA_}
query.setParameter("name", name); ~m:oJ+:O
return query.list(); (}Q(Ux@X
} >KPxksFR8
g=)B+SY'
/* (non-Javadoc) vO>Fj
* @see com.adt.dao.UserDAO#getUserCount() ,sw|OYb
*/ ?A4zIJ\
publicint getUserCount()throws HibernateException { N|JML
int count = 0; t1Ty.F)r
String querySentence = "SELECT count(*) FROM nHAET
eh\_;2P
user in class com.adt.po.User"; S#h-X(4
Query query = getSession().createQuery ~
_ ogeD
O+iNR9O
(querySentence); ''t\J^+&
count = ((Integer)query.iterate().next bSa%?laS
}
Xbmb8
()).intValue(); %rE:5)
return count; tuT>,BbR
} k
P]'
_}bs0 kIz
/* (non-Javadoc) I+08tXO
* @see com.adt.dao.UserDAO#getUserByPage pco:]3BF6
5;WESk
(org.flyware.util.page.Page) B* 0TM+
*/ Y-yozt
publicList getUserByPage(Page page)throws #mT\B[4h
.r ,wc*SF
HibernateException { &>nB@SQZ
String querySentence = "FROM user in class |ry![\
Z hqGUb
com.adt.po.User"; (,nQ7,2EX
Query query = getSession().createQuery k4N_Pa$}\
` nd/N#
(querySentence); 77 g<`}{
query.setFirstResult(page.getBeginIndex()) [3K& cX}B
.setMaxResults(page.getEveryPage()); pc/x&VY%
return query.list(); 8dPDs#Zl
} xG_LEk( zD
[TX1\*W
} mafnkQU
91f{qq=#J{
V^* ];`^
YR'dl_
WiU-syNh
至此,一个完整的分页程序完成。前台的只需要调用 e1<9:h+
=EJ8J;y_f
userManager.listUser(page)即可得到一个Page对象和结果集对象 \wjT|z1+Y
scc+r
的综合体,而传入的参数page对象则可以由前台传入,如果用 1tZ7%0R\g]
X%C`('"R
webwork,甚至可以直接在配置文件中指定。 u0Q6+U
*A&A V||q
下面给出一个webwork调用示例: ;*c8,I;
java代码: ?^3Y+)}
KPi_<LuK
?4`f@=}'K
/*Created on 2005-6-17*/ $)YalZ
package com.adt.action.user; nyoLrTs{
'048Qykt;
import java.util.List; t6q7w
d Dg[ry
import org.apache.commons.logging.Log; (Sv=R(_s
import org.apache.commons.logging.LogFactory; ;W 3#q:
import org.flyware.util.page.Page; H\%^n<]#
"g5<j p
import com.adt.bo.Result; ge#0Q L0K
import com.adt.service.UserService; 5)c B\N1u
import com.opensymphony.xwork.Action; Lo<WK
?]%ZJd
/** i,h)VCc
* @author Joa xe4`D>LUo
*/ 9^?2{aP%
publicclass ListUser implementsAction{ SuR+Vv
%!\iII
privatestaticfinal Log logger = LogFactory.getLog +@^FUt=tq
:
uxJGx
(ListUser.class); (.J6>"K<
M!`&Z9N
private UserService userService; 7VIfRN{5n
&q7}HO/ @
private Page page; !#Pr'm/,mu
?vBMx _0
privateList users; *ZkOZ
RRb>]oD
/* H73 r3BH
* (non-Javadoc) Pk3b#$+E
* ^/ff)'.J
* @see com.opensymphony.xwork.Action#execute() 79z/(T+
*/ t`-
[
publicString execute()throwsException{ 'WNq/z"X
Result result = userService.listUser(page); tjLG$M1z`
page = result.getPage(); !ra,HkU'
users = result.getContent(); J[{ R:l\
return SUCCESS; *DgRF/S
} /g>]J70
g8R@ol0
/** 8 \"A-+_Q
* @return Returns the page. I]z4}#+cX
*/ \"a~~Koe
public Page getPage(){ B)x^S
>
return page; 3:aj8F2
} !lL~#l:F
"sSY[6Kp!
/** !GJT-[
* @return Returns the users. I{$TMkh[
*/ I.gF38Mx
publicList getUsers(){ 3>v-,S+
return users; y&A&d-
} {(IHHA>
3V]08
/** )b~+\xL5J
* @param page hZ|8mV
* The page to set. ~bqw !rz
*/ +3k.xP?QS
publicvoid setPage(Page page){ k5|GN Y6a
this.page = page; {t*CSI
} O!'gylj/
{Ia1Wd 8n
/** G b4p"3
* @param users pwvmb\
* The users to set. ,z01*Yx
*/ x21XzGLY|}
publicvoid setUsers(List users){ GMY[Gd
this.users = users; mT>RQ.
} -;O"Y?ME
[1l OGck[
/** _n0NE0
* @param userService QuBA'4ht
* The userService to set. RNopx3
*/ Jim5Ul
publicvoid setUserService(UserService userService){ \('WS[$2
this.userService = userService; ?^ R"a##
} /&E]qc*-p
} Z kBWVZb
50dx[v8
pQxv_4
$T_>WUiK
+Mb}70^
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, jItVAmC=i
;D<;pW
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 VFK]{!C_
jFl!<ooCo
么只需要: T3Sz<K$E
java代码: pI1g<pe
qN^]`M[ BY
zhe~kI
<?xml version="1.0"?> g77 :92
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork .dn#TtQv
or"9I1o
1.0//EN" "http://www.opensymphony.com/xwork/xwork- )=!|^M
g)}q3-<AK>
1.0.dtd"> hGI5^!Cq
k_nQmU>
<xwork> 7e[&hea
RJ-J/NhWyI
<package name="user" extends="webwork- jw)c|%r>
psuK\s
interceptors"> ky'G/z
BO+to.
<!-- The default interceptor stack name S
rhBU6K
TCK#bJ
--> {]iM5?
<default-interceptor-ref Y=/;7T
4m%Yck{R
name="myDefaultWebStack"/> Qnx?5R-}ZU
xiVbVr#[
<action name="listUser" #+
{%>f
KvjH\;78
class="com.adt.action.user.ListUser"> L+lX$k
<param %r@:7/
O4!!*0(+91
name="page.everyPage">10</param> a_zf*;
<result #dFE}!"#`
yQq|!'MK k
name="success">/user/user_list.jsp</result> [KMS/'; ]
</action> {>3w"(f7o
Bw.?Me)mf|
</package> D7Ds*X`!l
g(R!M0hdF
</xwork> P!!:p2fo
JHuA}f{2&
r@Xh8
r;
;+n25_9
g@m__
@2eH;?uO
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 /S9n!H:MT
&-KQ
m20n
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 `a8 &7J(
91ec^g
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 y(j vl|z[
i x_a
+$R%Vbd
_@Y17L.
LbnF8tj}h
我写的一个用于分页的类,用了泛型了,hoho fK{Z{)D
b{,vZhP-
java代码: j?(@x>HA
.p'\@@o5
RPkOtRKL=w
package com.intokr.util; DCgiTT\
7??j}ob>
import java.util.List; (`d _DQ
hOe$h,E']
/** q X]ej2
* 用于分页的类<br> _<jccQ
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Mvk#$:8e
* *jl_,0g]
* @version 0.01 !^3j9<|@'
* @author cheng Y|<1|wGG
*/ ROj=XM:+
public class Paginator<E> { ~{D:vj4>
privateint count = 0; // 总记录数 h)T-7b
privateint p = 1; // 页编号 F5<GGEQb
privateint num = 20; // 每页的记录数 _p| KaT``
privateList<E> results = null; // 结果 '~7 6Y9mv
[jF\"#A
/** $I a-go2W
* 结果总数 ^Y^5 @x=
*/ NmV][0(BS
publicint getCount(){ HgRfMiC
return count; ]2xoeNF/W{
} {N0ky=ud
cWa>rUsF
publicvoid setCount(int count){ DO?
bJ01
this.count = count; =e]Wt/AQ
} ]K%D$x{+\
Ay\!ohIS3
/** Mp^U)S+
* 本结果所在的页码,从1开始 mGUl/.;yp-
* #J4,mFMr
* @return Returns the pageNo. "#`c\JuR]
*/ }q~xr3#
publicint getP(){ :w4I+*]
return p; z|G 39
} $]iRfXv,l!
XXZ$^W&
/** @_Ly^'
"
* if(p<=0) p=1 Pl[WCh
* #e;\Eap
* @param p 7033#@_
*/ e7gWz~
publicvoid setP(int p){ b"z9Dp v
if(p <= 0) %suXp,j
p = 1; P
C
this.p = p; 2n5{H fpY
} :6Sb3w5h
+yu^Z*_
/** |y7#D9m
* 每页记录数量 %LZf=`:(
*/ d:=:l?
publicint getNum(){ 2BIOA#@t
return num; J Y@x.?N5$
} `!g
XA.9Uv
qbdv
/** UkBr4{+aE
* if(num<1) num=1 ;hp?wb
*/ ppM^&6x^
publicvoid setNum(int num){ '^.}5be&
if(num < 1) 4S#q06=Xe
num = 1; !Pb39[f
this.num = num; 'D;'Pr]
} gw9:1S
)haHI)xR
/** *G0r4Ui$
* 获得总页数 -* ;`~5
*/ #$9rH
2zd
publicint getPageNum(){ ^!>o5Y)
return(count - 1) / num + 1; @uI_4 a
} v:$Y
|mh
jP|(y]!
/** T Jp0^&Q
* 获得本页的开始编号,为 (p-1)*num+1 :j0r~*z-
*/ (s.S
n(E
publicint getStart(){ ur2`.dY>3"
return(p - 1) * num + 1; K-*q3oh
G
} e#$ZOK)`
goV[C]|
/** (eAh8^)
* @return Returns the results. UZ+FV;<
*/ Bx32pY
publicList<E> getResults(){ JMq00_
return results; Px))O&w{
} ~8G<Nw4*\
L3-tD67oa
public void setResults(List<E> results){ :S5B3S@|
this.results = results; D;al(q
} 0Ie9T1D=
.v:K`y;f\(
public String toString(){ fX2PteA0qX
StringBuilder buff = new StringBuilder S?_ ;$Cn
3QrYH
@7zx
(); X pd^^
buff.append("{"); ii@O&g
buff.append("count:").append(count); DOm5 azO!>
buff.append(",p:").append(p); B[0XzV]Z
buff.append(",nump:").append(num); %%w]-`^h,
buff.append(",results:").append 3q.O^`y FU
L_YVe(dT
(results); >2l;KVm%
buff.append("}"); T+[N-"N
return buff.toString(); ]='E&=nc
} {<- BU[H
O5Xu(q5+
} {^#62Y
w(9.{zF|vQ
eOQUy+