Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 p5*Y&aKj
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 >HDK<1 >
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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 anbr3L[!
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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 _Cs.%R!r
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分页支持类: a?;{0I:Ln
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java代码: pd|s7
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package com.javaeye.common.util; nm)F tX|A
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import java.util.List; ("{'],>
*(rq AB0~
publicclass PaginationSupport { SF6n06UZu
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publicfinalstaticint PAGESIZE = 30; |qBo*OcO
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privateint pageSize = PAGESIZE; Vrnx#j-U
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privateList items; TCVJ[LbJ
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privateint totalCount; ?h{ &
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privateint[] indexes = newint[0]; 8WAg{lVs
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privateint startIndex = 0; <v\|@@X
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public PaginationSupport(List items, int U@9n7F
6 R!0v8
totalCount){ 8?PNyO-Wt5
setPageSize(PAGESIZE); *+b[v7
setTotalCount(totalCount); Zffzyh
setItems(items); Z'\_YbB
setStartIndex(0); de"*<+
} d+_qBp
yJ^}uw
public PaginationSupport(List items, int Q$3%aR-2
8NLk`/
totalCount, int startIndex){ Eq|_>f@@8
setPageSize(PAGESIZE); :S.0e
setTotalCount(totalCount); L"IdD5`7T
setItems(items); 4u<oe_n
setStartIndex(startIndex); [u<1DR
} ?xy~N?N
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public PaginationSupport(List items, int )0NA*<Q+.
us/x.qPy2
totalCount, int pageSize, int startIndex){ n04Zji(F@
setPageSize(pageSize); V< J~:b1V
setTotalCount(totalCount); P?>p+dM
setItems(items); Ef#%4ky
setStartIndex(startIndex); C\1Dy5
} =!Ok079{[
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publicList getItems(){ /
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return items; I(C_}I>Wb
} $} ~:x_[
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publicvoid setItems(List items){ N/Z<v* i"
this.items = items; g4Tc (k#
} +YP,LDJ!v
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publicint getPageSize(){ [~x
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return pageSize; ,<%],-Lt[
} O<fbO7.-
9'}m797I'
publicvoid setPageSize(int pageSize){ q$K^E
this.pageSize = pageSize; PQ1\b-I
} .Zo8KwkFY
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publicint getTotalCount(){ @;pTQ
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return totalCount; S/8xo@vct]
} d<xBI,g
@dGj4h.
publicvoid setTotalCount(int totalCount){ =*}|y;I
if(totalCount > 0){ lE /"
this.totalCount = totalCount; J PmW0wM
int count = totalCount / h T4fKc7P
u" nyx0<
pageSize; tlc&Wx
if(totalCount % pageSize > 0) !tN]OQ)'
count++; |XPT2eQ{
indexes = newint[count]; QH;1*
for(int i = 0; i < count; i++){ ;|66AIwDe
indexes = pageSize * 68d(6?OgW
$6R<)]6
i; |NL$? %I
} XBCz\f
}else{ \
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this.totalCount = 0; {,,w5/k^
} 6:@tHUm
} f ~9ADb
@va6,^)
publicint[] getIndexes(){ 7|*|xLrVY
return indexes; ]^R;3kU4Q
} Jgb{Tl:r
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publicvoid setIndexes(int[] indexes){ dnH?@K
this.indexes = indexes; s<tdn[d
} yo3'\I
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publicint getStartIndex(){ /&a[D2
return startIndex; VcA87*pel
} /=i^Bgh4
>$k_tC'"
publicvoid setStartIndex(int startIndex){ )~s(7
4`}
if(totalCount <= 0) os"o0?
this.startIndex = 0; L=?Yc*vg
elseif(startIndex >= totalCount) }m(u oT~
this.startIndex = indexes 0OP6VZ\
t\S}eoc
[indexes.length - 1]; weKwBw
elseif(startIndex < 0) .(ki(8Z N
this.startIndex = 0; 58{6k J@
else{ S+7>Y? B!
this.startIndex = indexes %3|0_
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[startIndex / pageSize]; P'R!"
#
} 7C
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} :voQ#f=
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publicint getNextIndex(){ }qRYXjS
int nextIndex = getStartIndex() + uveTx
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pageSize; {O[a+r.n
if(nextIndex >= totalCount) N.l+9L0b
return getStartIndex(); 7&qunK'
else >XM-xK-=
return nextIndex; }PUQvIGZZ&
} ^3^n|T7le
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publicint getPreviousIndex(){ ^g"G1,[%w
int previousIndex = getStartIndex() - >iDV8y
`a*[@a#
pageSize; Tm
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if(previousIndex < 0) S)T~vK(n
return0; iG!tRNQ{y
else g kT`C
return previousIndex; jA?A)YNQb
} c=0S]_
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} Ivmiz{Oii
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抽象业务类 bx#GOK-
java代码: !uL z%~F
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/** [Abq("9p\
* Created on 2005-7-12 w^6rgCl
*/ `A_CLVE
package com.javaeye.common.business; GWsvN&nr
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import java.io.Serializable; ycz6-kEp
import java.util.List; )"`(+Ku&c
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import org.hibernate.Criteria; wuRQ
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import org.hibernate.HibernateException; Z]V^s8>
import org.hibernate.Session; B4Ko,=pg
import org.hibernate.criterion.DetachedCriteria; ["TUSf]
import org.hibernate.criterion.Projections; l 8qCg/ew
import O~?H\2S
1t w>C\
org.springframework.orm.hibernate3.HibernateCallback; roSdcQTeT
import % put=I
|`B*\\ 1
org.springframework.orm.hibernate3.support.HibernateDaoS ^lud2x$O^C
S:aAR*<6
upport; w\ 4;5.$
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import com.javaeye.common.util.PaginationSupport; 7Ko<,Kp2b
gG*]|>M JI
public abstract class AbstractManager extends f3El9[
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HibernateDaoSupport { +GqK$B(x7
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privateboolean cacheQueries = false; b&BkT%aA(G
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privateString queryCacheRegion; W}{RJWr
-5B>2K F
publicvoid setCacheQueries(boolean (cAWT,
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cacheQueries){ gT8Q:8f:
this.cacheQueries = cacheQueries; z=%&?V
} :59fb"^$
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publicvoid setQueryCacheRegion(String OCHjQc
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f
queryCacheRegion){ G%5bQ|O
this.queryCacheRegion = $23*:)&J4
W}jel}:
queryCacheRegion; PIOG|E
} %EV\nwn6
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publicvoid save(finalObject entity){ eYNu78u
getHibernateTemplate().save(entity); 6bPoC$<Z
} w1U2cbCr/
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publicvoid persist(finalObject entity){ [.:SV|AF#
getHibernateTemplate().save(entity); pV:;!+
} E/+H~YzO
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publicvoid update(finalObject entity){ y#tuwzE
getHibernateTemplate().update(entity); zNG]v?JAh
} ', +YWlW
)bqSM&SO
publicvoid delete(finalObject entity){ ufl[sj%^|
getHibernateTemplate().delete(entity); =c/jS
} ZW+M<G
{o>51fXc)
publicObject load(finalClass entity, w8veh[%3n
H#/ #yVw
finalSerializable id){ @G'&7-(h*
return getHibernateTemplate().load *ay&&S*
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(entity, id); Bk)E]Fk|
} }SD*@w
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publicObject get(finalClass entity, hSkI]%
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finalSerializable id){ vNWCv
return getHibernateTemplate().get X 8/9x-E_
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(entity, id); /6fa
7;
} Sjb[v
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publicList findAll(finalClass entity){ |NMf'$
return getHibernateTemplate().find("from 3g79pw2w=
)\aCeY8o
" + entity.getName()); h95a61a,Vy
} W0-KFo.'
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publicList findByNamedQuery(finalString v[l={am{/
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namedQuery){ YzA6*2
return getHibernateTemplate QH>e_
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().findByNamedQuery(namedQuery); wqnrN6$jf
} mv,p*0
n3z]&J5fr
publicList findByNamedQuery(finalString query, Z-U-n/6I
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finalObject parameter){ >PbB /->
return getHibernateTemplate 'v^Zterr
dgEH]9j&
().findByNamedQuery(query, parameter); 2K:Rrn/cR
} 6[x6:{^J
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publicList findByNamedQuery(finalString query, h/goV
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finalObject[] parameters){ 57|RE5]|!
return getHibernateTemplate 9M12|X\]8
}+@GgipyO.
().findByNamedQuery(query, parameters); kO3N.t@n
} x&
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publicList find(finalString query){ !+EE*-c1c
return getHibernateTemplate().find E\Qm09Dj`<
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(query); ITssBB9
} 'g5 Gdn
UG !+&ii|
publicList find(finalString query, finalObject "L9yG:
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parameter){ aam6R/4
return getHibernateTemplate().find XM#xxf* Y
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(query, parameter); e+~Q58oD
} L,\wB7t
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public PaginationSupport findPageByCriteria dje}CbZ
c0U=Hj@@
(final DetachedCriteria detachedCriteria){ {t%Jc~p{
return findPageByCriteria FW@(MIH
zn)Kl%N^
(detachedCriteria, PaginationSupport.PAGESIZE, 0); EEJ OJ<
} 2kSN<jMr
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public PaginationSupport findPageByCriteria aj`_*T"A
}K.2
(final DetachedCriteria detachedCriteria, finalint 59MpHkr
Dg=!d)\
startIndex){ .,*68S0k7
return findPageByCriteria UFl+|wf
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(detachedCriteria, PaginationSupport.PAGESIZE, ,ZWaTp*D/
MszX9wl
startIndex); o+0x1Ct3P
} (#Ku`
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public PaginationSupport findPageByCriteria ^q}cy1"j"
d:!A`sk7
(final DetachedCriteria detachedCriteria, finalint oMeIXb)z
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pageSize, FzzV%
finalint startIndex){ "8l&m6`U-
return(PaginationSupport) b?]Lx.l-
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getHibernateTemplate().execute(new HibernateCallback(){ E[a|.lnV
publicObject doInHibernate igO,Ge8}
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(Session session)throws HibernateException { 1m4Xl%KS>
Criteria criteria = (x!Tb2mlk
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detachedCriteria.getExecutableCriteria(session); ;)XB'
int totalCount = 7 (kC|q\4M
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((Integer) criteria.setProjection(Projections.rowCount MO%kUq|pg
231,v,X[
()).uniqueResult()).intValue(); vp4NH]fJ
criteria.setProjection ^~DDl$NH
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(null); 5H79-QLd
List items = = P@j*ix
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criteria.setFirstResult(startIndex).setMaxResults | k?r1dj%O
:cA%lKg
(pageSize).list(); ,SG-{
PaginationSupport ps = \'hZm%S
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new PaginationSupport(items, totalCount, pageSize, L/KiE+Y
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startIndex); fq<JX5DER
return ps; s ;2ih)[
} BI|YaZa+p
}, true); :lE_hY
} TsF>Y""*M
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public List findAllByCriteria(final =-%10lOI
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DetachedCriteria detachedCriteria){ z,K;GZuP
return(List) getHibernateTemplate =berCV
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().execute(new HibernateCallback(){ )8&;Q9'o
publicObject doInHibernate jBMGm"NE
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(Session session)throws HibernateException { []l2
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Criteria criteria = .C\##
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detachedCriteria.getExecutableCriteria(session); b]6@
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return criteria.list(); \(`8ng]vs
}
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}, true); 3L^]J}|
} @/W~lJ!e
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public int getCountByCriteria(final Z/G?wD|B
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DetachedCriteria detachedCriteria){ 1"wZ [.
Integer count = (Integer) T)o>U&KNP
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getHibernateTemplate().execute(new HibernateCallback(){ !g7lJ\B
publicObject doInHibernate 1LVO0lT
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(Session session)throws HibernateException { H;c3 x"
Criteria criteria = vf;&0j&`
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detachedCriteria.getExecutableCriteria(session); \e9rXh%
return svvl`|n%
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criteria.setProjection(Projections.rowCount i`^[_
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()).uniqueResult(); >/.w80<'
} #?C.%kD
}, true); 2y5d
return count.intValue(); mX5%6{],
} O)$Pvll
} tA8O(9OV
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用户在web层构造查询条件detachedCriteria,和可选的 * zt?y
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 bbs'>D3
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PaginationSupport的实例ps。 ^v5<* uf%m
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ps.getItems()得到已分页好的结果集 YL&)@h
ps.getIndexes()得到分页索引的数组 Q!y%N&
ps.getTotalCount()得到总结果数 `8/D$
ps.getStartIndex()当前分页索引 J%FF@.)k
ps.getNextIndex()下一页索引 ;6M [d
ps.getPreviousIndex()上一页索引 z\`tnz7>$
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} 89-U
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 M(?0c}z
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,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 ha?M[Vyw4Q
dJ{q}U
一下代码重构了。 iAo/Dnp2J
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我把原本我的做法也提供出来供大家讨论吧: $38)_{
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首先,为了实现分页查询,我封装了一个Page类: k~*%Z!V}C
java代码: .Ta (v3om%
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/*Created on 2005-4-14*/ G%ZP`
package org.flyware.util.page; G|YNShK4=9
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/** m5v IS
* @author Joa 8a3EVc
* [@_W-rA
*/ .(99f#2M:
publicclass Page { /2'l=R5#
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/** imply if the page has previous page */ E>iN >
privateboolean hasPrePage; xqb*;TBh*
3EHB~rL/C
/** imply if the page has next page */ :(iBLO<x
privateboolean hasNextPage; C55Av%-=
tl;b~k
/** the number of every page */ 20# V?hX3
privateint everyPage; l5#SOo\
=!\Y;rk
/** the total page number */ p\R&vof*
privateint totalPage; !Df>Q5~g
.C` YO2,
/** the number of current page */ zpjE_|
privateint currentPage; ~@DdN5
!t+ 3DMPn
/** the begin index of the records by the current 4]#$YehM5
7,zE?KG /
query */ wYr*('uT
privateint beginIndex; d(yTz&u)
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/** The default constructor */ Y,Lx6kU
public Page(){ 5> lIrBf
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} #{?~XS
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/** construct the page by everyPage 9Dbbk/j|
* @param everyPage }3_>
* */ 7"F29\
public Page(int everyPage){ a 7685Y
this.everyPage = everyPage; j^%N:BQ&
} \ef:H&r
^HxIy;EQ<z
/** The whole constructor */ I1Otu~%d
public Page(boolean hasPrePage, boolean hasNextPage, yfal'DqKF
74 &q2g{
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int everyPage, int totalPage,
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Pc^
int currentPage, int beginIndex){ %lD+57=
this.hasPrePage = hasPrePage; txvo7?Y*4
this.hasNextPage = hasNextPage; O4Q"2
this.everyPage = everyPage; `?O0)
this.totalPage = totalPage; jtUqrJFlQ
this.currentPage = currentPage; &isKU8n
this.beginIndex = beginIndex; AvPPsN0
} OJd/#KFm
U(LLIyZv
/** +~~2OU L
* @return 0HUylnXf0
* Returns the beginIndex. yO}5.
*/ lu8*+.V
publicint getBeginIndex(){ 3=yfbO<-
return beginIndex; ITg<u?z_
} ~GcWG4
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/** Xdwpn+7s
* @param beginIndex ,ga6
* The beginIndex to set. )_1 GPS
*/ 2WTOu x*
publicvoid setBeginIndex(int beginIndex){ s_a jA
this.beginIndex = beginIndex; \EsT1aT
} ~>HzAo9e
UOk\fyD2[
/** $
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* @return bAbR0)
* Returns the currentPage. lj UdsU w
*/ l&}}Io$?@
publicint getCurrentPage(){ NSBcYObX
return currentPage; b]fx
} PfZS"yk
!LzA
/** !=A;?Kdq
* @param currentPage IrMB=pWo
* The currentPage to set. i")0 3b
*/ 8XG';K_
publicvoid setCurrentPage(int currentPage){ s*s~yH6
this.currentPage = currentPage; Q@7d:v
} Bp3E)l
<N1wET-
/** B]@25
* @return uKd4+Km
* Returns the everyPage. L,[Q{:C S
*/ ]8}51y8
publicint getEveryPage(){ ~MBPN4r
return everyPage; g;v;xlY`N
} fGO\f;P
^lAM /
/** TS#[[^!S
* @param everyPage nYFrp)DLK
* The everyPage to set. jn:_2g[
*/ |K"Q>V2y
publicvoid setEveryPage(int everyPage){ ZZ7qSyBs?
this.everyPage = everyPage; 7/
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} MUAs(M;
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/** kQ lU.J>^
* @return
fT|A^
* Returns the hasNextPage. UXs)$
*/ xC,x_:R`
publicboolean getHasNextPage(){ xEp?|Q$
return hasNextPage; Dlq!:dF{&
} KWZhCS?[(
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/** qh:Bc$S
* @param hasNextPage aPVzOBp
* The hasNextPage to set. |Ha#2pt{bc
*/ vWZXb`
publicvoid setHasNextPage(boolean hasNextPage){ u0c}[BAF
this.hasNextPage = hasNextPage; iN[x
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} =9X1 +x
68Gywk3]=u
/** BtZ]~S}v
* @return C/IF~<B
* Returns the hasPrePage. D]]wJQU2
*/ viG,z4Zf
publicboolean getHasPrePage(){ )63
$,y-;$
return hasPrePage; =c'4rJ$+
} F5Z,Jmi^M
d=PX}o^
/** _r*\ BM8y
* @param hasPrePage jYFJk&c
* The hasPrePage to set. [/CGV8+
*/ a:fP
publicvoid setHasPrePage(boolean hasPrePage){ U}RBgPX!
this.hasPrePage = hasPrePage; UowvkVa
} y
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#cu{AdK
/** _cX}!d!j
* @return Returns the totalPage. @"-\e|[N
* \</!kY*3@t
*/ kFv*>>X`
publicint getTotalPage(){ Zd6ik&S
return totalPage; P[2!D)A
} T&?g)
IT1YF.i
/** }/F$73Xd
* @param totalPage AJ bCC
* The totalPage to set. c3^!S0U
*/ _^r};}-}
publicvoid setTotalPage(int totalPage){ 9%"7~YCDas
this.totalPage = totalPage; U`%t&7)
} LE\=Y;%
^$K&Met
} Yv5H41o"
u4C9ZYN
U!aM63F3
V4n~Z+k
.eR1\IAm
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 r3l1I}
K*SgEkb'l
个PageUtil,负责对Page对象进行构造: USVDDqZ
java代码: 1f`De`zXzr
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:&IHdf0+
/*Created on 2005-4-14*/ jYHn J}<
package org.flyware.util.page; Dfs*~H63
s-$Wc)l
import org.apache.commons.logging.Log; dFm_"135
import org.apache.commons.logging.LogFactory; %
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5
2.D2
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/** wq$$.
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* @author Joa tk&AZb,sP
* \Ii{sn9
*/ n#lbfN 4
publicclass PageUtil { 9D T<
@C)s4{V
privatestaticfinal Log logger = LogFactory.getLog jE\G_>
VJ~D.ec
(PageUtil.class); wJy]Vyd
C !j3@EZ$
/** "do5@$p|
* Use the origin page to create a new page 3iCe5VF
* @param page QK]P=pE'C
* @param totalRecords Vu:ZG*^
* @return ;W,* B.~
*/ u?=mh`
publicstatic Page createPage(Page page, int x>yqEdR=o
x+X@&S
totalRecords){ r#sg5aS7O|
return createPage(page.getEveryPage(), jeu'K vhe
qGk.7wf%
page.getCurrentPage(), totalRecords); k=]e7~!
} 79T_9}M
Uwc%'=@
/** X:GRjoa
* the basic page utils not including exception g\q .
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handler FA+HR
* @param everyPage 6}^x#9\
* @param currentPage y2A\7&7
* @param totalRecords @t%da^-HS"
* @return page 74Jx \(d
*/ \ND]x]5d
publicstatic Page createPage(int everyPage, int \p4*Q}t
cNWmaCLN$
currentPage, int totalRecords){ $*C
}iJsF
everyPage = getEveryPage(everyPage); w2s`9
currentPage = getCurrentPage(currentPage); WLUgiW(0$
int beginIndex = getBeginIndex(everyPage, U%h.l
h/Mt<5
currentPage); TO6F
int totalPage = getTotalPage(everyPage, =XfvPBA
o?baiOkH
totalRecords); !db=Iz5)
boolean hasNextPage = hasNextPage(currentPage, @]Jq28
q8{Bx03m6
totalPage); imM!Me 0TE
boolean hasPrePage = hasPrePage(currentPage); Z",0 $Gxu
.I`>F/Sjr
returnnew Page(hasPrePage, hasNextPage, O*u
everyPage, totalPage, %J*1F
currentPage, Q9bnOvKe|
xA3_W
beginIndex); n!4}Hwz!
} n{?Du
V%R]jbHZ#
privatestaticint getEveryPage(int everyPage){ #Pd9i5~N
return everyPage == 0 ? 10 : everyPage; ([8*Py|
} `oxBIn*BD
mI&3y9; (
privatestaticint getCurrentPage(int currentPage){ r Ea(1(I
return currentPage == 0 ? 1 : currentPage; QbJ7$, 4
} f7&ni#^Ztj
GgpE"M?
privatestaticint getBeginIndex(int everyPage, int fzJiW@-T
JI@iT6.%IX
currentPage){ h4n~V:nNm
return(currentPage - 1) * everyPage; AROHe
} C. .| O
L1kn="5
privatestaticint getTotalPage(int everyPage, int ;~F*2)
Z\0wQ;}
totalRecords){ %DttkrhL
int totalPage = 0; !zK"y[V
ui?@:=
if(totalRecords % everyPage == 0) ]-wyZ +a
totalPage = totalRecords / everyPage; )u(,.O[cw
else r*{.|>me
totalPage = totalRecords / everyPage + 1 ; 7{r7
~BI`{/O=
return totalPage; 94!}
Z>
} _N5pxe`
27Gff(
privatestaticboolean hasPrePage(int currentPage){ |;J`~H"K
return currentPage == 1 ? false : true; 1feVFRx'
} Sstz_t
BsA4/Bf
privatestaticboolean hasNextPage(int currentPage, Bl>m`/\1i
;1~ n|IY
int totalPage){ nKE^km
return currentPage == totalPage || totalPage == "/R?XCBZsb
%qV:h#
0 ? false : true; Ea4zC|;
} ]+G
.S-a
1#Vd)vSP
ftn10TO *
} zW`Hqt;
/R|?v{S1
Da<`|
l
@Mya|zb
U/Cc!WXV]
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。 (%6fZ
O=K0KOj
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 \>\ERVEd
7b~uU@L`
做法如下: m2m
;|rr
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ,tXI*R
-medD G
的信息,和一个结果集List: $\m:}\%p
java代码: h8WM4
PK
X!V#:2JY
GYtgw9 "Y
/*Created on 2005-6-13*/ )-I/ej^
package com.adt.bo; ]R~hzo
{JdXn
import java.util.List; gR/?MJ(v
2 6}3
import org.flyware.util.page.Page; q"269W:
|zRrGQYm
/** BuvnY
* @author Joa ~"*W;|)
*/ ~APS_iG[
publicclass Result { ,OrrGwp&
TQ![
private Page page; Lt~&K$t7~
Eg&5tAyM
private List content; (0@b4}Z
I>8_gp\1
/** D<70rBf2
* The default constructor n"?*"Ya
*/ ~|<'@B!6
public Result(){ a?ete9Q+
super(); T:
My3&6
} %V1j M
N~b0 b;e
/** {.U:Ce
* The constructor using fields <0Y<9+g!
* K:13t|
* @param page ,5U[#6^
* @param content "kFNOyj3\
*/ NVQ.;" 2w
public Result(Page page, List content){ pSAtn
this.page = page; ,n%b~.$:v5
this.content = content; ,dd1/zm
} ml2/}}
AP`1hz4].-
/** ~[F7M{LS
* @return Returns the content. K20Hh7cVJ
*/ u-jV@Tz
publicList getContent(){ -F(luRBS(W
return content;
K#6@sas
} "([gN:
"1\GU1x
/** -k:x e:$
* @return Returns the page. ,yp#!gE~
*/ @8w[Z o~
public Page getPage(){ EhKG"Lb+
return page; #Mk3cp^Yl
} E>/~:
5MYdLAjV
/** #""T>+
* @param content 1.N2!:&G|
* The content to set. +tt!xfy
*/ 8*Fn02 p
public void setContent(List content){ '5Kj"aD%
this.content = content; +2tFX
} # bjK]+
l['p^-I
/** M*cF'go
* @param page FbMtor
* The page to set. y5KeUMcu
*/ LRaO}-<b
publicvoid setPage(Page page){ {2Ew^Li
this.page = page; :,yC\,H^
} >\~Er@
} "*`!.9pt
,o0Kev z
kVCWyZh4
T12Zak4.=
B1Pi+-t
2. 编写业务逻辑接口,并实现它(UserManager, LPs5LE[Pm
o\><e1P
UserManagerImpl) :+w6i_\d5
java代码: 2~QJ]qo =
db_}][;.c
vgDpo@fz8
/*Created on 2005-7-15*/ ZI4dD.B
package com.adt.service; F/1m&1t
B#`'h~(7
import net.sf.hibernate.HibernateException; SmvMjZ+7Y
\1#]qs -
import org.flyware.util.page.Page; Gj%q:[r
f.%3G+
import com.adt.bo.Result; h{zb)'R
h-O;5.m-P
/** ?7lW@U0
* @author Joa oa=TlBk<
*/ Z5F#r>> `
publicinterface UserManager { a[z$ae7
LXJ;8uW2y
public Result listUser(Page page)throws \Wg_ gA
qQ3pe:n?
HibernateException; 2"shB(:z>
QBi]gT@&g
} }CZw'fhVWO
JC9$"0d7
bZAL~z+ V
tcRJ1:d
a9 q:e
java代码: oclU)f.,
9c*B%A8J
")txFe
/*Created on 2005-7-15*/ 9LBZMQ
package com.adt.service.impl; An`*![
x@/:{B
import java.util.List; <]DUJuF-M
j_h:_D4
import net.sf.hibernate.HibernateException; _Yp~Oj
^A=tk!C
import org.flyware.util.page.Page; hosY`"X
import org.flyware.util.page.PageUtil; \o72VHG66
]auqf
import com.adt.bo.Result; !\BM
import com.adt.dao.UserDAO; v.4G>0 0^
import com.adt.exception.ObjectNotFoundException; n53c}^
import com.adt.service.UserManager; 3HuGb^SNg
6rD]6#D
/** nN-S5?X#
* @author Joa xs Pt
*/ )[M:#;,L
publicclass UserManagerImpl implements UserManager { ":s_O.
WcM\4q@
private UserDAO userDAO; >KdV]!H
);q~TZ[Do
/** #pK"
^O*!
* @param userDAO The userDAO to set. S-Bx`e9 '
*/ i'>5vU0?3
publicvoid setUserDAO(UserDAO userDAO){ )cP)HbOd=
this.userDAO = userDAO; 4 83rU
} 'DpJ#w\81
q{B?j%.o
/* (non-Javadoc) n|rKo<Y0
* @see com.adt.service.UserManager#listUser ~LOE^6C+~o
IFS_DW
(org.flyware.util.page.Page) R?9x!@BV
*/ hOj+z?
public Result listUser(Page page)throws f^"pZS
nu~]9~)I
HibernateException, ObjectNotFoundException { $)8,dS
int totalRecords = userDAO.getUserCount(); aH@-"Wi
if(totalRecords == 0) 5U+4vV/*
throw new ObjectNotFoundException O1t$]k:
kcg\f@d$
("userNotExist"); `=,emP&(H&
page = PageUtil.createPage(page, totalRecords); [2Nux0g
List users = userDAO.getUserByPage(page); s/C'f4
returnnew Result(page, users); LGW_7&0<<
} <m1v+cnqo
NW 2`)e'
} Kr|.I2?"
^[Ka+E^Q
O&|<2Qr
-<5{wQE;|
GQCdB>
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Z(Y:
d(ypFd9z
询,接下来编写UserDAO的代码: T{f$S
3. UserDAO 和 UserDAOImpl: Qe ip h
java代码: J,u-)9yBA<
fG$LqzyqlK
~gMt
U
/*Created on 2005-7-15*/
rJCb8x+5a
package com.adt.dao; gM=:80
m9i/rK_
import java.util.List; qnj'*]ysBC
|rZMcl/
import org.flyware.util.page.Page; LfFXYX^
$YcB=l
import net.sf.hibernate.HibernateException; '/@wk#,
]Zc|<f;
/** c-Yd> 4+1
* @author Joa >-<iY4|[d
*/ ^V96lKt/
publicinterface UserDAO extends BaseDAO { ;`:YZ+2
Z
1,bE[_
publicList getUserByName(String name)throws #+AQ:+
P+|L6w*|[
HibernateException; 3+h3?
'EXx'z;/#
publicint getUserCount()throws HibernateException; pWJEFm
(?zD!%
k
publicList getUserByPage(Page page)throws <"P-7/j3j
hdrsa}{g
HibernateException; p&]V!O
1hGj?L0m.
} X<[ qX*
|3@DCbT
hp9U
A!x &,<
pxd=a!(
java代码: bSX/)')jU
mJ k\$/Kh
)(-;H|]?
/*Created on 2005-7-15*/ DyGls8<\!
package com.adt.dao.impl; -YKy"
]FTi2B{}H
import java.util.List; T:Klr=&V
IY#:v%U
import org.flyware.util.page.Page; 9N}\>L)_
@y`xFPB
import net.sf.hibernate.HibernateException; G`>]ng
import net.sf.hibernate.Query; `a|&aj0
!.$L=>:V
import com.adt.dao.UserDAO; /+SLq`'u)
TxP+?1t
/** <L#d<lx
* @author Joa }>u `8'2v
*/ H%>4z3n
public class UserDAOImpl extends BaseDAOHibernateImpl y@!o&,,mq
g)#{<#*2
implements UserDAO { G,|!&=Pe|E
SNH 3C1
/* (non-Javadoc) # Q^".#
* @see com.adt.dao.UserDAO#getUserByName }a6t <m`V
VoZ{ I{>|
(java.lang.String) qVE0[ve
*/ ~RuX2u-2&u
publicList getUserByName(String name)throws c!4F0(n4
AT~,
HibernateException { E3wL n/<
String querySentence = "FROM user in class M }d:B)cz
M[YFyM(
com.adt.po.User WHERE user.name=:name"; r%ES#\L6+|
Query query = getSession().createQuery @>(KEjQTz
"/i$_vl
(querySentence); - Fbp!*.
u
query.setParameter("name", name); YoKyiO!
return query.list(); +)j ll#}?
} _q27
3QG/"
!EB<N<P"t
/* (non-Javadoc) hb5K"9Y
* @see com.adt.dao.UserDAO#getUserCount() ;J 5z
*/ x^f)I|t
publicint getUserCount()throws HibernateException { #lP8/-s^
int count = 0; ZLv/otf:|"
String querySentence = "SELECT count(*) FROM vv @m{,7#Y
.="XvVdkp
user in class com.adt.po.User"; fq6%@M~
Query query = getSession().createQuery ==5F[UX
}bjZeh.
(querySentence); FoyYWj?,R
count = ((Integer)query.iterate().next w!7\wI[
Y7VO:o
()).intValue(); YzI;)
return count; D%YgS$p[M$
} MCT1ZZpPr
Fr8GGN~/
/* (non-Javadoc) }#O!GG{
* @see com.adt.dao.UserDAO#getUserByPage oY18a*_>M1
}p7iv:P=3
(org.flyware.util.page.Page) }6c>BU}DF
*/ ijF_
KP'
publicList getUserByPage(Page page)throws ssi7)0
MePD:;mm^
HibernateException { JF.Lo;
String querySentence = "FROM user in class B ;1qy[
~.m<`~u
com.adt.po.User"; F3qK6Ah.
Query query = getSession().createQuery /9w>:i81
!LI<%P)
(querySentence); ~9dpB>+
query.setFirstResult(page.getBeginIndex()) L8QWEFB|
.setMaxResults(page.getEveryPage()); .gRj^pu
return query.list(); _8VP'S=
} senK(kbc
@LKQ-<dZG
} HgF;[rq3Q
)\fY1WD
$RaN@& Wm
*glZb;_
+$,Re.WnP
至此,一个完整的分页程序完成。前台的只需要调用 O<gfZ>
'-;[8:y.
userManager.listUser(page)即可得到一个Page对象和结果集对象 e<L@QNX
7^q~a(j
的综合体,而传入的参数page对象则可以由前台传入,如果用 m|@H`=`d
9Eyx Ob
webwork,甚至可以直接在配置文件中指定。 ~?Q sr
9oWU]A\k>
下面给出一个webwork调用示例: !+T1kMP+l
java代码: ?['!0PF
}vd*eexA
SiratkP9n7
/*Created on 2005-6-17*/ SAx9cjj+
package com.adt.action.user; ]k0
jmE
NK_|h%
import java.util.List; {m.$EoS
<>cS@V5j
import org.apache.commons.logging.Log; }rTH<!j
import org.apache.commons.logging.LogFactory; du3f'=q6|
import org.flyware.util.page.Page; _IYaMo.n
%BqaVOKJ"f
import com.adt.bo.Result; k9^Hmhjw
import com.adt.service.UserService; 0s#72}n
import com.opensymphony.xwork.Action; ,5}U
H
'$K E=Jy
/** G 6sK3K
* @author Joa f!Q\M1t)
*/ T~TP
publicclass ListUser implementsAction{ yB*,)x0
@
FK|O^->B
privatestaticfinal Log logger = LogFactory.getLog `2s!%/
+K57. n{
(ListUser.class); _u`YjzK
Mqf Ns<2
private UserService userService; ^mS |ff
'y8{,R4C
private Page page; kI{DxuTad
4q$~3C[
privateList users; `@]s[1?f
c7Z4u|G
/* Zp_(vOc
* (non-Javadoc) -Mt
5< s
* [4Z 31v>
* @see com.opensymphony.xwork.Action#execute() XpQ Ol
*/ S&op|Z)1
publicString execute()throwsException{ U=on}W3V2
Result result = userService.listUser(page); gV_/t+jI
page = result.getPage(); ^u/%zL
users = result.getContent(); a^|DD#5
return SUCCESS; dhl[=Y`
Q
} BT$p~XB
n/H
OP
/** 5gszAvOO
* @return Returns the page. Wgq|Q*
*/ OG,P"sv
public Page getPage(){ sGvbL-S-f:
return page; \U~4b_aN
} S:\i
M:
)xGAe#E~j
/** [uq>b|`RG
* @return Returns the users. !Brtao"m
*/ yC,/R371k
publicList getUsers(){ WeI+|V$
return users; |D3u"Y!:^
} Q M,!-~t
&K)8
/** weitDr6
* @param page wucdXj{%
* The page to set. l.[pnL D
*/ cPGlT"
publicvoid setPage(Page page){ |m19fg3u
this.page = page; "(koR Q
} Gn]36~)*H
.p`4>XA
/** g|=_@
pL
* @param users WA{igj@\
* The users to set. F /b`[
*/ X>%nzY]m
publicvoid setUsers(List users){ 3P>gDQP
this.users = users; _`$LdqgE
} )vr@:PE
J(
}2Ua_
/** @u3`lhUcT
* @param userService ^6 6!f 5^W
* The userService to set. H^_,e= j
*/ 1C[9}}
publicvoid setUserService(UserService userService){ y!e]bvN
this.userService = userService; }fpya2Xt
} bRC243]g*A
} #%"q0"
4 p_C+4
MatXhP] Fi
(iIw}f)w
&{iC:zp
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, r@r%qkh(.@
0r]n
0?x
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 0QQss
<?jdNM
么只需要: 93-Y(Xx)bY
java代码: ~m%[d.
}e
yev!Nw
V la,avON
<?xml version="1.0"?> IS C.~q2
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork C2LPLquD+
~PQ.l\C
1.0//EN" "http://www.opensymphony.com/xwork/xwork- NGra/s,9|
~{c ?-qb
1.0.dtd"> ]5W$EvZ9)
lwnO
<xwork> }ze+ tf
I8*VM3
<package name="user" extends="webwork- ;'!x
!\]^c
interceptors"> (Guzj*1 2
]{-.?W*$
<!-- The default interceptor stack name jA? #!lx_
NgNGq\!
--> Hg+<GML
<default-interceptor-ref P{L=u74b{x
}v(wjD
name="myDefaultWebStack"/> 6*8Wtq
vr!J3H f
<action name="listUser" "SF0b jG9C
Y~ ~Dg?e
class="com.adt.action.user.ListUser"> 9#LMK 1ge
<param ,'NasL8?We
.^YxhUH,G
name="page.everyPage">10</param> p_r` "
<result 337.' |ZE
ROO*/OOd
name="success">/user/user_list.jsp</result> ?7{U=1gb$
</action> 5Z=4%P*I
*%-<Ldv
</package> .soCU8i3
}A9#3Y|F
</xwork> Xj?Wvt
QxT'\7f
~C-Sr@ a?/
*miG<
#ydold{F
#J5BHY~
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 :]"5UY?oF
OY*y<