Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ?\8?%Qk
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 EGl^!.'
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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 DcSnia62f
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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 |yo\R{&6
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分页支持类:
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java代码: |lv|!]qAma
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package com.javaeye.common.util; &~CY]PN.
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import java.util.List; tE7[Smzuf
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publicclass PaginationSupport { }MUn/ [x
JI vo_7{
publicfinalstaticint PAGESIZE = 30; %Qk/_ R1
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privateint pageSize = PAGESIZE; "kZ[N'z(
KD^N)&k^Kp
privateList items; ws^4?O
i*CZV|t US
privateint totalCount; 8b0d]*q
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privateint[] indexes = newint[0]; }<'5 z
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privateint startIndex = 0; q{+_
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public PaginationSupport(List items, int z3uW)GQ.
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totalCount){ |g*XK6
setPageSize(PAGESIZE); %w7]@V Z
setTotalCount(totalCount); ES40?o*]x
setItems(items); V\6]n2
setStartIndex(0); r;m)nRu
} H<1WbM:w
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public PaginationSupport(List items, int VWO9=A*Y|
cp o-.
totalCount, int startIndex){ @$T 9Ll
setPageSize(PAGESIZE); _/O25% l
setTotalCount(totalCount); zhf.NCSt(
setItems(items); f^VP/rdg
setStartIndex(startIndex); Y/7 $1k
} XQS9,Hl
u,6~qQczE
public PaginationSupport(List items, int -I=l8m6L
%RDI!e<e}
totalCount, int pageSize, int startIndex){ 5<w g8y
setPageSize(pageSize); l<N}!lG|
setTotalCount(totalCount); P@FHnh3}Z$
setItems(items); D::rGB?.b
setStartIndex(startIndex); ) Yd?m0m*
} a1@Y3MQ;i
k-}b{
publicList getItems(){ ^_m9KA
return items; v;)..X30
} AnT3M.>ek
8]LD]h)B"
publicvoid setItems(List items){ y99mC$"Ee`
this.items = items; Jkek-m
} S9#)A->
KY~-;0x
publicint getPageSize(){ ow]053:i
return pageSize; `*shF9.\C
} CvD"sHVq%
ynrT a..
publicvoid setPageSize(int pageSize){ {E8~Z8tT
this.pageSize = pageSize; S;-
LIv
} wH@Ns~[MA
@/31IOIV]`
publicint getTotalCount(){ =y-@AU8
return totalCount; 7"C$pm6
} Z+=@<i''
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publicvoid setTotalCount(int totalCount){ L'kmNVvYN
if(totalCount > 0){ X93!bB
this.totalCount = totalCount; SBS3?hw
int count = totalCount / J7g8D{4
t)}scf&^x
pageSize; :n-]>Q>5=k
if(totalCount % pageSize > 0) i ,/0/?)*_
count++; ^=-y%kp"
indexes = newint[count]; &:`U&06q
for(int i = 0; i < count; i++){ uwy:t!(j
indexes = pageSize * :w^Ed%>y7
]'=)2
.}
i; q1KZ5G)6GJ
} W*I(f]8:y`
}else{ io8'g3<
this.totalCount = 0; fd.^h*'mU
} OD!& .%
} ?BZ PwGMs
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publicint[] getIndexes(){ #$8% w
return indexes; oc >{?.^
} ~
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2HsLc*9{4
publicvoid setIndexes(int[] indexes){ )u`[6,d
this.indexes = indexes; /^#;d
UB
} fUA uqfj[
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publicint getStartIndex(){ 8b;1FQ'
return startIndex; 2KYw}j|5
} hFy;ffs.
kTu[ y;
publicvoid setStartIndex(int startIndex){ heC/\@B
if(totalCount <= 0) naR0@Q"\h
this.startIndex = 0; lHPd"3HDK
elseif(startIndex >= totalCount) sl`s_$J
this.startIndex = indexes VoWNW
zv\kPfGDK
[indexes.length - 1]; b((M)Gz
elseif(startIndex < 0) ijK"^4i
this.startIndex = 0; !C3MFm{B
else{ b)qoh^
this.startIndex = indexes I%j|D#qY:T
eo?;`7
[startIndex / pageSize]; DN-+osPi
} AicBSqUke
} _M`--.{\O[
2q=AEv/
publicint getNextIndex(){ jD<{t
int nextIndex = getStartIndex() + c|B.n]Z
:*Z4yx
pageSize; rrBsb -
if(nextIndex >= totalCount) KyYM fC
return getStartIndex(); Mb|a+,:>3
else C.Kh[V\Ut
return nextIndex; 6z#acE1)M
} /'l{E
NV72
publicint getPreviousIndex(){ Oj3.q#)`Z
int previousIndex = getStartIndex() - w[zjerH3
'MUv5Th
pageSize; l1OE!W W
if(previousIndex < 0) `>f6)C-
return0; "55skmD.P
else (|:M&Cna]
return previousIndex; "U>JM@0DNm
} |ef7bKU8
r~jm`y
} &:9cAIe]H
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抽象业务类 X0bN3N
java代码: ~dgDO:)
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/** F\JM\{&F
* Created on 2005-7-12 f9t6q*a`%
*/ [842&5Pd?
package com.javaeye.common.business; 0=@?ob7
@r/#-?W
import java.io.Serializable; -LK
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import java.util.List; &S{RGXj_
"bFTk/
import org.hibernate.Criteria; s@&`f{
import org.hibernate.HibernateException; twL3\
}N/B
import org.hibernate.Session; V+*
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import org.hibernate.criterion.DetachedCriteria; lGPUIoUo
import org.hibernate.criterion.Projections; A -H&
import $UMFNjL
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org.springframework.orm.hibernate3.HibernateCallback; ]
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import |{BIHgMh
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org.springframework.orm.hibernate3.support.HibernateDaoS <C1H36p
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upport; ^=BTz9QM
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import com.javaeye.common.util.PaginationSupport; D"Bl:W'?j
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public abstract class AbstractManager extends y6ECdVF
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HibernateDaoSupport { ]{)a,c NG
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privateboolean cacheQueries = false; G"-?&)M#a
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privateString queryCacheRegion; S@jQX
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publicvoid setCacheQueries(boolean JmF l|n/H
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cacheQueries){ |jQ:~2U|
this.cacheQueries = cacheQueries; 0ZT5bg_M
} _D+}q_
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publicvoid setQueryCacheRegion(String `>gd&u
> A Khf
queryCacheRegion){ X^T:8npxt
this.queryCacheRegion = KK1gNC4R
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queryCacheRegion; @KWb+?_H{<
} Q}1 R5@7
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publicvoid save(finalObject entity){ !9u|fnC9
getHibernateTemplate().save(entity); .\[`B.Q
} |*oZ_gI
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publicvoid persist(finalObject entity){ bt"W(m&f
getHibernateTemplate().save(entity); kY&k-K\
} aUzBV\Yd}
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publicvoid update(finalObject entity){ %@wJ`F2a_
getHibernateTemplate().update(entity); iWRH{mK
} ~rlB'8j(
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publicvoid delete(finalObject entity){ >/:" D$
getHibernateTemplate().delete(entity); ~o82uw?
} rx $mk
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publicObject load(finalClass entity, E%+Dl=
)hd@S9Z.Y
finalSerializable id){ vGc,vjC3x
return getHibernateTemplate().load " W!M[qBW
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(entity, id); bBu,#Mc
} G'rxXJq
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publicObject get(finalClass entity, 0]>u)%
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finalSerializable id){ <:(6EKJAq}
return getHibernateTemplate().get VcAue!MN
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(entity, id); GT~)nC9f
} 9iXeBC
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publicList findAll(finalClass entity){ XOxr?NPQ^
return getHibernateTemplate().find("from jYx38_5e
guX
9}
" + entity.getName()); s4G|_==
} ICuF %
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publicList findByNamedQuery(finalString JCz@s~f\y
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namedQuery){ @_U;9)
return getHibernateTemplate E_Im^a
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().findByNamedQuery(namedQuery); A&s:\3*Kh
} eKgisY4#
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publicList findByNamedQuery(finalString query, f_[<L
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finalObject parameter){ Ae
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return getHibernateTemplate >GQEqXs
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().findByNamedQuery(query, parameter); >^%7@i:@U
} SPN5dE.@
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publicList findByNamedQuery(finalString query, KQacoUHrK?
M9EfU
finalObject[] parameters){ `^bgUmJ~
return getHibernateTemplate '#s05hr
Uh7v@YMC
().findByNamedQuery(query, parameters); b}0,\B%
} JXCCTUO
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publicList find(finalString query){ cU0s
p
return getHibernateTemplate().find *4_jA](
QF{4/y^j{
(query); ~(x;5{
} $tz;<M7B
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publicList find(finalString query, finalObject ?z}=B
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parameter){ P/xKnm~
return getHibernateTemplate().find 20vXSYa~
{S,l_d+(
(query, parameter); dlJbI}-v=
} Of{/t1o?
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public PaginationSupport findPageByCriteria /V8}eZ97
^\\Tx*#i
(final DetachedCriteria detachedCriteria){ mocI&=EF2X
return findPageByCriteria )jkXSTZ
j{Hao\F8
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ul2R'"FB
} R<sJ^nx
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public PaginationSupport findPageByCriteria ^&bRX4pYo
Vl_:c75"
(final DetachedCriteria detachedCriteria, finalint NG
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startIndex){ m>4ahue$
return findPageByCriteria ^xh}I5
M&NB/
(detachedCriteria, PaginationSupport.PAGESIZE, IB#
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startIndex); LEW'G"+
} T.Ryy"%F
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public PaginationSupport findPageByCriteria si&S%4(
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(final DetachedCriteria detachedCriteria, finalint y]J89
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pageSize, l5\"9 ,<
finalint startIndex){ %Eb%V ($
return(PaginationSupport) ms!r ef4`+
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getHibernateTemplate().execute(new HibernateCallback(){ R,9[hNHWGs
publicObject doInHibernate HPb]Zj
F)s{P Cl
(Session session)throws HibernateException { ([-|}
Criteria criteria = ?;vgUO
" R-!(9k^`
detachedCriteria.getExecutableCriteria(session); 4'-|UPhx
int totalCount = JJ{9U(`_y6
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((Integer) criteria.setProjection(Projections.rowCount 9G{;?c
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()).uniqueResult()).intValue(); X{we/'>
criteria.setProjection .&9 i
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(null); jM$`(Y
List items = 3t<a $i
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criteria.setFirstResult(startIndex).setMaxResults 6ezS {Q
} ~"hC3w
(pageSize).list(); zN{K5<7o
PaginationSupport ps = uu}x@T@
X=Ys<TM,
new PaginationSupport(items, totalCount, pageSize, "Kc>dJ@W
H|ER
startIndex); -S$1Yn
return ps; 05snuNt]-
} ,RgB$TcE
}, true); ]~6_ WE8L
} /DqLrA
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public List findAllByCriteria(final :.?gHF.?
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DetachedCriteria detachedCriteria){ %e`$p=m
return(List) getHibernateTemplate K
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jMbC Y07v
().execute(new HibernateCallback(){ B 9T!j]'
publicObject doInHibernate Xe#K{gA
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(Session session)throws HibernateException { p|Q*5TO
Criteria criteria = Vpr/
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detachedCriteria.getExecutableCriteria(session); # [e
return criteria.list(); t\RF=BbJJ
} O/.Uh`T`6
}, true); lip[n;Ir>
} M@3"<[g
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public int getCountByCriteria(final A<6%r7&B'
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DetachedCriteria detachedCriteria){ }?&k a$rI
Integer count = (Integer) mo1oyQg8
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getHibernateTemplate().execute(new HibernateCallback(){ 4;HJ;0-ps
publicObject doInHibernate Qfky_5R\
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(Session session)throws HibernateException {
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Criteria criteria = 8/t$d#xHI
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detachedCriteria.getExecutableCriteria(session); i 9g>9
return `\X+ Ud|
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criteria.setProjection(Projections.rowCount =CL}
$_
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()).uniqueResult(); `fNG$ODL
} `)qVF,Z}
}, true); Ne$"g[uFU
return count.intValue(); ,v&L:a
} VdP`a(Yd;
} {QbvR*gv
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用户在web层构造查询条件detachedCriteria,和可选的 PyA&ZkX>
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 s/:Fwr4q#a
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PaginationSupport的实例ps。 ,Rx{yf]k
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ps.getItems()得到已分页好的结果集 n6(i`{i
ps.getIndexes()得到分页索引的数组 "lNzGi-H
ps.getTotalCount()得到总结果数 +3i7D
ps.getStartIndex()当前分页索引 9s}Kl($
ps.getNextIndex()下一页索引 SEl#FWR
ps.getPreviousIndex()上一页索引 s4 %(>Q
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 24Z]%+b*E
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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 PuxK?bwC
*n(> ^
一下代码重构了。 x'Pi5NRE
o5\b'hR*#
我把原本我的做法也提供出来供大家讨论吧: A =Dhod
gPzL*6OSA
首先,为了实现分页查询,我封装了一个Page类: ha;l(U>
java代码: <DH*~tLp2
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/*Created on 2005-4-14*/ 4R>zPEo
package org.flyware.util.page; }<MR`h1
4z:#I;
/** v&g0ta@
* @author Joa oUx[+Gnv
* -{|`H[nmD
*/ TO;.eN!sv
publicclass Page { J
NC
8_uzpeRhJc
/** imply if the page has previous page */ j1Yq5`ia
privateboolean hasPrePage; vMSW$Bx ;
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/** imply if the page has next page */ |!d"*.Q@F
privateboolean hasNextPage; ^T4Ay=~{
7s'- +~
/** the number of every page */ Snf"z8sw
privateint everyPage; q}L+/+b
iO!6}yJ*V
/** the total page number */ P\~{3U
privateint totalPage; h3u1K>R)
t~K%.|'0
/** the number of current page */ i cUT<@0
privateint currentPage; 9x~-*8aw
"oc$
/** the begin index of the records by the current m.%`4L^`T
OCyG_DLT$5
query */ H!IDV}dn
privateint beginIndex; 7CvD'QW /
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j kn^Z":
/** The default constructor */ _; ]e@
public Page(){ 2%rLoL$Y2+
pe04#zQK
} ,8K'F
RU!?-#*
/** construct the page by everyPage |ek
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* @param everyPage X} JOX9pK
* */ (wt+`_6
public Page(int everyPage){ }HZ{(?
this.everyPage = everyPage; eG]a zt
} {E,SHh
E[Bo4?s&^
/** The whole constructor */ !G=>ve
public Page(boolean hasPrePage, boolean hasNextPage, gT1P*N;v
d!{7r7ob\
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int everyPage, int totalPage, Ky9W/dCR
int currentPage, int beginIndex){ 9R]](g#
this.hasPrePage = hasPrePage; )+~E8yK
this.hasNextPage = hasNextPage; WfVMdwz=
this.everyPage = everyPage; aw$Y`6,S
this.totalPage = totalPage; VWvoQf^+
this.currentPage = currentPage; w7Dt1axB
this.beginIndex = beginIndex; $p6N|p
} >!BFt$sd
%!W%#U0
/** wGXwzU
* @return E$S`6+x`:a
* Returns the beginIndex. #EwK"S~
*/ G(OFr2M
publicint getBeginIndex(){ P/aDd@j
return beginIndex; "3y} F
} ,YlQK;
6"%qv`.Fp
/** V*qY"[
* @param beginIndex /yK"t<p
* The beginIndex to set. ?`. XK}
*/ `p|[rS>
publicvoid setBeginIndex(int beginIndex){ SfDQ;1?
this.beginIndex = beginIndex; Bcaw~WD
} "?H+
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$^$ECDOTB
/** 22vq=RO7Z
* @return 0M\NS$u(Y
* Returns the currentPage. zPBfiK_hV
*/ "^"'uO$
publicint getCurrentPage(){ uGCtLA+sL
return currentPage; j |td,82.
} m<FK;
sRi %1r7
/** ?#ihJt,
* @param currentPage ?pKN'`
* The currentPage to set. msG3~@q
*/ R-C5*$
publicvoid setCurrentPage(int currentPage){ dJE`9$jN
this.currentPage = currentPage; L]>4Nd
} Lupy:4AD
=M7PvH'"
/** j@SYXKL~
* @return }{=8&gA0
* Returns the everyPage. MA"#rOcP
*/ *o2#eI
publicint getEveryPage(){ 25&nwz
return everyPage; X#7}c5^Y
} U%,;N\:_
khS/'b
/** $2is3;h
* @param everyPage ?q6Z's[
* The everyPage to set. /Mx.:.A&$
*/ 1W0.Ufl)
publicvoid setEveryPage(int everyPage){ :@;6
this.everyPage = everyPage; O sB?1;:
} r
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mCK],TOA:
/** 1V0sl0i4
* @return ik1XGFy?
* Returns the hasNextPage. YPG,9iZ&f
*/ qkiJH T
publicboolean getHasNextPage(){ i<Q&
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return hasNextPage; Tfr`?:yF
} b.@H1L
q$|0)}
/** 5U3qr*/ ;m
* @param hasNextPage D| [/>x
* The hasNextPage to set. /[6:LnaE
*/ f~U#z7
publicvoid setHasNextPage(boolean hasNextPage){ S;>4i!Mb
^
this.hasNextPage = hasNextPage; '%);%y@v
} gh'kUZG
a
OCwW@OC +
/** <3)|44.o&
* @return 8F\~Wz 7K
* Returns the hasPrePage. #g F2(iK6
*/ [6G=yp
publicboolean getHasPrePage(){ WI0QLR'
return hasPrePage; (I>HWRH
} ypgliq(
4v0dd p
/** <|B$dz?r
* @param hasPrePage ?ISI[hoc
* The hasPrePage to set. vwm|I7/w
*/ f 5mY;z"
publicvoid setHasPrePage(boolean hasPrePage){ >).@Nb;e
this.hasPrePage = hasPrePage; /4(Z`e;0
} >c}:
.mC~Ry+t
/** KSF5)CZ5
* @return Returns the totalPage. =_K%$y*
* b=V)?"e-
*/ TlM'g6SQS
publicint getTotalPage(){ +[>yO _}
return totalPage; 2;dM:FHLhO
} an-\k*w
!&'# a
/** jQY>9+t
* @param totalPage ]lymY _ >
* The totalPage to set. Up_>y>x
*/ 3s3a>
publicvoid setTotalPage(int totalPage){ j7QBU
this.totalPage = totalPage; 9` OG
} ac2}3$u
zG&WWc`K
} J&
1X
&gY;`*<
tpN]evp|
|U8>:DE l
#N<s^KYG-
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 Q3 K;kS
gn-=##fT:i
个PageUtil,负责对Page对象进行构造: 43UJ#rF
java代码: trID#DT~
_Ym&UY.u#
{LR#(q$1
/*Created on 2005-4-14*/ QT7w::ht
package org.flyware.util.page; S/#) :,YS
$#6Fnhh}
import org.apache.commons.logging.Log; a7QlU=\
import org.apache.commons.logging.LogFactory; WyKUvVi
Y!K^-Y}
/** O+CF/ipX/
* @author Joa v*vub#wP
* $ioaunQKP
*/ o+)m}'T8
publicclass PageUtil { n?TO!5RZK
7)ES!C
privatestaticfinal Log logger = LogFactory.getLog z/c'Z#w%
_*OaiEL+:
(PageUtil.class); :Su 5
LH?gJ8`
/** E-*>f"<h
* Use the origin page to create a new page #R"9)vHp
* @param page BP7<^`i&
* @param totalRecords MSxU>FX0
* @return VNOK>+
*/ }RC.Q`b
publicstatic Page createPage(Page page, int ThT.iD[
<uWJ>sg^6
totalRecords){ $w2[5|^S
return createPage(page.getEveryPage(), LiHXWi{s
DI2S
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page.getCurrentPage(), totalRecords); qB`0^V
} L@^!(
y7}~T!UyfF
/** )nbyV a
* the basic page utils not including exception 6832N3=
`"bRjC"f]
handler 5BGv^Qb_2
* @param everyPage `siy!R
* @param currentPage &`\kb2uep
* @param totalRecords v~W6yjp
* @return page O7L6Htya
*/ * Kp ^al
publicstatic Page createPage(int everyPage, int 2-B8>-
.,iw2:
currentPage, int totalRecords){ .bY1N5=sz
everyPage = getEveryPage(everyPage); u0$5Fd&X
currentPage = getCurrentPage(currentPage); )9;kzp/
int beginIndex = getBeginIndex(everyPage, ~jrU#<'G9
G@l|u
currentPage); *^&iw$Qx3
int totalPage = getTotalPage(everyPage, :;gwdZ
EzY
scX.[
totalRecords); B+e~k?O] 1
boolean hasNextPage = hasNextPage(currentPage, RAXJsF^5o
X#\P.$
totalPage); %@,:RA\pm
boolean hasPrePage = hasPrePage(currentPage); 4QN6BZJ5
nh_xbo5L[
returnnew Page(hasPrePage, hasNextPage, &b#NF1Q.
everyPage, totalPage, $F==n4)
currentPage, E<.{
v\
hc~#l #
beginIndex); J1wGK|F~
} BtDgv.;GH
iOA3x 8J
privatestaticint getEveryPage(int everyPage){ #on fac- 3
return everyPage == 0 ? 10 : everyPage; d`rDEa
} r;s3(@[,@
vcUM]m8k
privatestaticint getCurrentPage(int currentPage){ #p^pvdvh3
return currentPage == 0 ? 1 : currentPage; _a02#
} m_Y}>
L``mF(R^
privatestaticint getBeginIndex(int everyPage, int sZ(Q4)r
c[eGpZ]
currentPage){ PfMOc+ q
return(currentPage - 1) * everyPage; ]4pC\0c
} ;@$, "
P
So0,)
privatestaticint getTotalPage(int everyPage, int XcW3IO
"B{xC}Tw
totalRecords){ +vY`?k`
int totalPage = 0; ?>Ci`XlLr
qv >(
if(totalRecords % everyPage == 0) oZ>]8vw
totalPage = totalRecords / everyPage; AZm)$@e)
else qQ\hUii
totalPage = totalRecords / everyPage + 1 ; D}C*8s bC}
VHkrPJ[
return totalPage; C3
c|@7FU
} 9n2%7dLQ*
BJ;c F"Kp
privatestaticboolean hasPrePage(int currentPage){ Q? |M BTo
return currentPage == 1 ? false : true; %y~]3XWik
} M>l+[U
N1zrfn-VU
privatestaticboolean hasNextPage(int currentPage, PbC>v
04LVa|Y@U
int totalPage){ rY+1s^F
return currentPage == totalPage || totalPage == l3
Bc
g
:BiR6>1:
0 ? false : true; Tp.iRFFkP
} >Qu^{o
?DTP-#5Ba
@Pg@ltUd
} S~`AnX3!
x"=q+sA
rm;"98~zJ?
`Y$5g~3.
mqxy(zS]
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 _A~gqOe
HBYpjxh
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 uw&,pq
<W{0@?y
做法如下: qOanu
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 L*Cf&c`8r
meWq9:z
的信息,和一个结果集List: ~&jCz4M
java代码: `)P_X4e]`
Lu5.$b
Q2PwO;E.`C
/*Created on 2005-6-13*/ RlL,eU$CS
package com.adt.bo; +`[Sv%v&L
H( m+rk
import java.util.List; cC]1D*Bn
SZ){1Hu
import org.flyware.util.page.Page; q{(&:~M
W.<<azi
/** h0pr"]sO;$
* @author Joa }e @-[RJ!
*/ VG7#6)sQoK
publicclass Result { vGDo?X~#o
k,(_R=
private Page page; ' 1nU[,Wj
I-hhHm<@
private List content; a06q-3zw
{P+[CO
/** <ZdNPcT<s
* The default constructor A4x3TW?
*/ x=)$sD-3
public Result(){ _\[G7
super(); bq]a8tSB
} _Y=yR2O
!}7m^
/** zBfBYhS-
* The constructor using fields >AJ|F)
* mws.)
* @param page sxtGl^,mU:
* @param content :P~Owz
*/ a/fYD2uNo
public Result(Page page, List content){ }XU- JAn
this.page = page; @d|9(,Q
this.content = content; N5DS-gv
} tAUMSr|?
ZxQP,Ys_Y
/** d\M
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* @return Returns the content. >wwEa4
*/ Viw3 /K
publicList getContent(){ =UY@,*q:c
return content; Ok!{2$P8U9
} Z)%p,DiNM
+L6d$+
/** |*i-Q @
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* @return Returns the page. jC%I]#!n
*/ Pl4d(2
7
public Page getPage(){ 2_Z60]
return page; )SuJK.IF
} bkTj
Q
:|Cf$2k7
/** ,")7uMZaF\
* @param content wlJ1,)n^2
* The content to set. z~qQ@u|
*/ 566EMy|
public void setContent(List content){ )<d8y Lb
this.content = content; {$^|^n5j
} ln5On_Wm
9EEHLx"
/** k>"I!&#g
* @param page .kVga+la?
* The page to set. V.J%4&^X
*/ jo;n~>3P
publicvoid setPage(Page page){ .JE7vPv%!
this.page = page; n !QjptQ
} W3b\LnUa
} pyKMi /)bL
l-&f81W
8'y|cF%U
lk80)sTZ
=LR UasF
2. 编写业务逻辑接口,并实现它(UserManager, #!2gxm;g
y$WS;#
UserManagerImpl) E]
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java代码: rTH@PDk>)
B?jF1F!9
*;Vq0a!
/*Created on 2005-7-15*/ T*oH tpFj#
package com.adt.service; B~^\jRd"
Xe5J
import net.sf.hibernate.HibernateException; ;(XSw%Y
H
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import org.flyware.util.page.Page; fqcyCu7Ep
&HWH
UWB
import com.adt.bo.Result; Z"n]y4h
;j$84o{
/** J(Bn
n
* @author Joa ]SQ_*$`
*/ pH4i6B*5
publicinterface UserManager { #8PjYB
IflpM ]
public Result listUser(Page page)throws sIyLW
w(vf>L6(
HibernateException; VR'w$mp
U*-%V$3+w5
} @gZ%>qe
j#-74{Y$
J
D,NjDIG8
7QQnvoP
&B))3WFy
java代码: =~R0U
&R 0BuFL8
$Q?UyEi
/*Created on 2005-7-15*/ a+]@$8+
package com.adt.service.impl; j3$KYf`T}
U7{,
*
import java.util.List; 9;:Lf
-1fT2e
import net.sf.hibernate.HibernateException; C<{k[!N%zm
9D&ocV3QV
import org.flyware.util.page.Page; J H6\;G6
import org.flyware.util.page.PageUtil; _v_ak4m>
,UY],;ib
import com.adt.bo.Result; 3Y>!e#
import com.adt.dao.UserDAO; `2GHB@S"k
import com.adt.exception.ObjectNotFoundException; RsY|V|<
import com.adt.service.UserManager; {AJspLcG
[7$.)}Q-
/** ^ng?+X>mP
* @author Joa y+@7k3"
*/ EWbFy"=
publicclass UserManagerImpl implements UserManager { ao Y"uT+
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private UserDAO userDAO; -$t#AYKz
Rs7=v2>I
/** l\a 0 k4
* @param userDAO The userDAO to set. Ow<=K:^
*/ $:SHZe
publicvoid setUserDAO(UserDAO userDAO){ jeC3}BL}
this.userDAO = userDAO; S$ dFz
} N _Yop
nCJ)=P.d
/* (non-Javadoc) RY/9Ku `
* @see com.adt.service.UserManager#listUser ,{=#
3
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(org.flyware.util.page.Page) dk# LAm0<
*/ g7rn|<6FI
public Result listUser(Page page)throws "I}3*s9Q-
V'^Hn?1^
HibernateException, ObjectNotFoundException { &V:iy
int totalRecords = userDAO.getUserCount(); )u`q41!
if(totalRecords == 0) +g>)Bur
throw new ObjectNotFoundException ".Luc7
Q!iM7C!8
("userNotExist"); 3[amCKel
page = PageUtil.createPage(page, totalRecords); Qk*`9
List users = userDAO.getUserByPage(page); R#DnV[!\
returnnew Result(page, users); sFuB[
JJ}
} >/9f>d?w^
v=R=K
} 1/:WA:]1,
;*Ldnj;B
<k+dJ=f
j}ywdP`a
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 yY_Zq\
Qyx%:PE
询,接下来编写UserDAO的代码: B>hf|.GI
3. UserDAO 和 UserDAOImpl: D,b'1=
java代码: PUZH[-:c
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+}[M&D
/*Created on 2005-7-15*/ Au~l
O
package com.adt.dao; F,5~a_GP?
]-]K4*{
import java.util.List; cBZ$$$v\#
9K,PT.c
import org.flyware.util.page.Page; 8T-/G9u
}@6ws/5
import net.sf.hibernate.HibernateException; wX<w)@
[}:;B$,
/** !1(*D*31
* @author Joa PgHe;^?j
*/ o?5m^S14[1
publicinterface UserDAO extends BaseDAO { rMr:\M]t
u|(;SY
publicList getUserByName(String name)throws SzXR],dA
-J &y]'
HibernateException; tBUn
KPT
b:B+x6M
publicint getUserCount()throws HibernateException; gug9cmA/Q7
Mbm'cM&}
publicList getUserByPage(Page page)throws t?Ku6Z'
~cr##Ff5
HibernateException; (>49SOu;$\
'Nkd *
} m3#rU%Wj
VEsIhjQ
5nV IC3N+1
'8w}m8{y
GBYeiEgZh
java代码: h;[<4zw
M"\Iw'5$
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/*Created on 2005-7-15*/ v`r![QpYf
package com.adt.dao.impl; TI/5'Oke$
$sxRRem{?
import java.util.List; O2qy[]km
kk>z,A4
h_
import org.flyware.util.page.Page; ^]5^p9Jt"e
C;3
import net.sf.hibernate.HibernateException; 8-B6D~i
import net.sf.hibernate.Query; b|-}?@&7&q
??#SQSU
import com.adt.dao.UserDAO; 'pnOHT
D_q"|D$SB
/** :i3
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* @author Joa 6$)FQ
U
*/ %(1Jt"9|
public class UserDAOImpl extends BaseDAOHibernateImpl +!Q*ie+q
g4 3(N!@g
implements UserDAO { %p:Z(zU
Q{|_"sfJ
/* (non-Javadoc) 0qq>(K[
* @see com.adt.dao.UserDAO#getUserByName .uinv
oj/#wF+
(java.lang.String) *X5<]{7c
*/ <A(Bq'eQM
publicList getUserByName(String name)throws 7,s5Gd-
sd9b9?qiu
HibernateException { v|MT^.
String querySentence = "FROM user in class 7|xu)zYB
4T]A!
y{
com.adt.po.User WHERE user.name=:name"; )Ma/]eZ^I
Query query = getSession().createQuery U.WXh(`%
Gs\D`|3=
(querySentence); (tyky&$!
query.setParameter("name", name); JEs@ky?{z
return query.list(); 34QW^{dgE
} ~s
yWORiXm
_pmo
6O
/* (non-Javadoc) "G^TA:O:=
* @see com.adt.dao.UserDAO#getUserCount() 3Vbt(K
*/ {+]tx46$
publicint getUserCount()throws HibernateException { ==UYjbuU
int count = 0; -
~4na{6x
String querySentence = "SELECT count(*) FROM T^F83Py<
v>HOz\F
user in class com.adt.po.User"; xYZ,.
Query query = getSession().createQuery P4zwTEk`
+v~x_E5FP
(querySentence); *\@RBJGF
count = ((Integer)query.iterate().next cF_`QRtO
NG`Y{QT6N
()).intValue(); UM`{V5NG#
return count; sH>`eqY
} R58NTPm
Nw*F1*v`
/* (non-Javadoc) +hKs
* @see com.adt.dao.UserDAO#getUserByPage r
\[|'hA
D.-G!0!
(org.flyware.util.page.Page) ?pcbso
*/ 6O,:I
publicList getUserByPage(Page page)throws ^BM !TQ%!
xXc>YTK'
HibernateException { rd<43
String querySentence = "FROM user in class {bADMj1
WzoI0E`
com.adt.po.User"; *u:,@io7'G
Query query = getSession().createQuery 6)p8BUft
{F2Rv
(querySentence); )[J@s=
query.setFirstResult(page.getBeginIndex()) '6})L
.setMaxResults(page.getEveryPage()); PO8Z2"WI
return query.list(); j "'a5;Sy
} o2=):2x
r{
gL-kI*Ra
} D(;+my2
wViTMlq
Jfk#E^1
y631;dU
6T|Z4f|
至此,一个完整的分页程序完成。前台的只需要调用 39hep8+
XI ;] c5
userManager.listUser(page)即可得到一个Page对象和结果集对象 SMIDW}U2S
|(ab0b #
的综合体,而传入的参数page对象则可以由前台传入,如果用 vBOY[>=
Il9xNVos#
webwork,甚至可以直接在配置文件中指定。 {@iLfBh5
sT"ICooc
下面给出一个webwork调用示例: x s\<!
java代码: ?d3FR!
l"(PP3
-(F}=o'
/*Created on 2005-6-17*/ k2$pcR,WM
package com.adt.action.user; ;4ybkOD
W4&8
import java.util.List; Pj]^p{>
'G~i;o 2
import org.apache.commons.logging.Log; ?gUraSFU
import org.apache.commons.logging.LogFactory; (*P`
import org.flyware.util.page.Page; [ i,[^
|" WL
import com.adt.bo.Result; O|+ZEBP
import com.adt.service.UserService; .`m|Uf#"
_
import com.opensymphony.xwork.Action; :d9GkC
K<:%ofB"S
/** $.pCoS]i
* @author Joa &gruYZGK
*/ i a!!jK}
publicclass ListUser implementsAction{ 2F`#df
gJr)z7W'8
privatestaticfinal Log logger = LogFactory.getLog gJX"4]Ol#}
[n| }>
(ListUser.class); $)"T9$>$
&hkD"GGe
private UserService userService; v5L+B`~
Z2m^yRQ(
private Page page; P$Vh{]4i{
e|~{X\l
privateList users; P8ej9ULX,
DJgM>&Y6,
/* .<>t2,Af
* (non-Javadoc) ?OF$J|h
* -XL?n/M
* @see com.opensymphony.xwork.Action#execute() l<uI-RX"
*/ 0@b<?Ms9
publicString execute()throwsException{ /nA>ox78
Result result = userService.listUser(page); CHv
n8tk
page = result.getPage(); \mGb|aF8
users = result.getContent(); QxE%C
return SUCCESS; 2= ;ZJ
} Zy3F%]V0
A\rY~$Vr
/** *(q{k%/M
* @return Returns the page. m`fdf>gWp
*/ EH2):
public Page getPage(){ M5+R8ttc
return page; Q+K]:c
} <ZZfN@6
=v\}y+
Yh
/** UV;I6]$}A7
* @return Returns the users. M^WoV
}'
*/ M_E$w$l2<
publicList getUsers(){ g=4P-i3
return users; ~P,Z@|c4
} : ciwh
otjT?R2g'
/** K6B6@
* @param page ~8k`~t!
* The page to set. gf9,/m
*/ 7]L}~
publicvoid setPage(Page page){ S?v;+3TG
this.page = page; fvTp9T\f3
} :k.>H.8+~
GPs4:CIgG
/** o%]b\Vl6
* @param users %:l\Vhhz
* The users to set. 8j&1qJx)
*/ 2-g 5Gb2|
publicvoid setUsers(List users){ C\C*@9=&x
this.users = users; :Oj!J&A
} 2V9"{F?
H9VdoxKo
/** 3WkrG.$[b
* @param userService :]\-GJV5
* The userService to set. 78Zb IL
*/ kbz+6LcV
publicvoid setUserService(UserService userService){ y>UQm|o<W
this.userService = userService; )u!}`UJ
} ]a~gnz&1
} R^I4_ZA
_3KfY
!qs~j=;y3
= p2AK\
=cR=E{20
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, 14-uy.0[
v>Kv!OY:c
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 <