Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 uh.;Jj;
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?Be}{Qqlg
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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 7q;`~tbC
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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 EAXl.Y.
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分页支持类: S2\;\?]^~
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java代码: %GY'pQz
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package com.javaeye.common.util; uY>M3h#qx
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import java.util.List; `)cH(Rj
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publicclass PaginationSupport { u_+iH$zA
ff R%@
publicfinalstaticint PAGESIZE = 30; 6@8t>"}
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privateint pageSize = PAGESIZE; %1jcY0zEQ
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privateList items; JttDRNZAU
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privateint totalCount; y9d"sqyh
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privateint[] indexes = newint[0]; *-Yw%uR
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privateint startIndex = 0; =$)M-;6
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public PaginationSupport(List items, int IaSpF<&Y;
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totalCount){ MYjc6@=cR
setPageSize(PAGESIZE); ojlyW})$%
setTotalCount(totalCount); +e2:?d@
setItems(items); 4P1}XYD-2
setStartIndex(0); ej}S{/<*n
} 2yg6hR
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public PaginationSupport(List items, int p$|7T31 *
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totalCount, int startIndex){ MaHP):~
setPageSize(PAGESIZE); ;9h;oB@
setTotalCount(totalCount); %EVgS F!r
setItems(items); hPNMp@Nm6
setStartIndex(startIndex); #I453
} w5%i
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public PaginationSupport(List items, int :zKMw=
4L8hn4F
totalCount, int pageSize, int startIndex){ R^/SBrWve
setPageSize(pageSize); /<8y>
setTotalCount(totalCount); X)~wB7_0G
setItems(items); 4RtAwB
setStartIndex(startIndex); Ws`ndR
} /qIl)+M
RfTGTz@H
publicList getItems(){ 7g"u)L&32
return items; ^O+ (eA7E
} >god++,o
_7;:*'>a4
publicvoid setItems(List items){ \298SH(!7
this.items = items; ; iia?f1
} /o m++DxV
;H~<.QW
publicint getPageSize(){ NvJ5[W
return pageSize; ~o%igJ
}.C
} xH*X5?
/
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publicvoid setPageSize(int pageSize){ |0=UZK7%O
this.pageSize = pageSize; ,n8\y9{G
} sNo8o1Hby
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publicint getTotalCount(){ b),fz
return totalCount; 3*=0`}jMJ
} aU_Hl+;
rT/r"vr
publicvoid setTotalCount(int totalCount){ "hf
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if(totalCount > 0){ _i+@HXR &
this.totalCount = totalCount; ={ms@/e/T
int count = totalCount / {JP q.A
%?PFe}
pageSize; A'KH_])
if(totalCount % pageSize > 0) \|S!g_30m
count++; [|KvlOvP
indexes = newint[count]; ?PT>V,&
for(int i = 0; i < count; i++){ v wEbGx
indexes = pageSize * nlNk
qt~=47<d
i; ~.%HZzR6&
} <ErX<(0`ig
}else{ Y"MHs0O5>
this.totalCount = 0; l,4O
} ~x9]?T
} 3J+2#ML
rR#Ditn^
publicint[] getIndexes(){ U;MXiE3D
return indexes; ;[Mvk6^'R
} 9KXL6#h
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publicvoid setIndexes(int[] indexes){ ^'V :T Y
this.indexes = indexes; T[bC Y 6
} ~_D.&-xUF
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publicint getStartIndex(){ h<LFTYE@
return startIndex; E7MSoBX9M
} Fye>H6MU
f_jhQ..g<g
publicvoid setStartIndex(int startIndex){ AzOs/q8O
if(totalCount <= 0) A#=TR_@:
this.startIndex = 0; <:}nd:l1
elseif(startIndex >= totalCount) H3D<"4Q>
this.startIndex = indexes 8D*nU3O
jb.H[n,\
[indexes.length - 1]; v4n< G-
elseif(startIndex < 0) Vb(b3
this.startIndex = 0; (.ir"\k1(
else{ Db,"Gl
this.startIndex = indexes -^xbd_'
@x}"aJgl
[startIndex / pageSize]; @&ZQDi
} yWi-ic
[n
} DW. w=L|5R
RSp wU;o6z
publicint getNextIndex(){ .$18%jH#
int nextIndex = getStartIndex() + q<dG}aj
*5%vU|9b
pageSize; nF,F#V8l
if(nextIndex >= totalCount) &<PIm
return getStartIndex(); P]43FPb
else V\;Xa0
return nextIndex; K*>%,mP$i
} J-v1"7[2GC
XMrk2]_
publicint getPreviousIndex(){ U)/.wa>
int previousIndex = getStartIndex() - <.6rl
JLoF!MK}
pageSize; %f;dn<m=c
if(previousIndex < 0) E~%n-A
return0; h1w({<q*ov
else l6/VJ~(}'
return previousIndex; K92j BR
} m4mE7Wn.3
O[Vet/^)
} MuoE~K2
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抽象业务类 bhqSqU}6~
java代码: h_%q`y ,
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/** 4)S99|1
* Created on 2005-7-12 zjpZ] $
*/ srGOIK.
package com.javaeye.common.business; 0MW W(
;
.kT]^rv
;
import java.io.Serializable; yLnQ9BXB&
import java.util.List; t6DSZ^Zq
3uLG$`N
import org.hibernate.Criteria; q+?<cjVg
import org.hibernate.HibernateException; {R}F4k
import org.hibernate.Session; DB/~Z
import org.hibernate.criterion.DetachedCriteria; q/#e6;x
import org.hibernate.criterion.Projections; 4q}+8F`0F
import @J[@Pu O
X1Yw=t~a
org.springframework.orm.hibernate3.HibernateCallback; F]\
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import t'n@yX_
3UZd_?JI[^
org.springframework.orm.hibernate3.support.HibernateDaoS x-BU$bx5
@^{`!>Vt
upport; Xs0)4U
M/N8bIC! Q
import com.javaeye.common.util.PaginationSupport; vO}r(kNJ
bA^uzE
public abstract class AbstractManager extends _~<sb,W
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HibernateDaoSupport { uvId],dQ5
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privateboolean cacheQueries = false; 8q^}AT<C
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privateString queryCacheRegion; [G<ga80
yw^Pok5.
publicvoid setCacheQueries(boolean
(dy(.4W\
Q{[@n
cacheQueries){ >q"dLZ
this.cacheQueries = cacheQueries; `i.BB jx`
} {VcRur}&Y8
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publicvoid setQueryCacheRegion(String n'~==2
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queryCacheRegion){ m5K?oV@n
this.queryCacheRegion = 9&lemz
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queryCacheRegion; Coi[cfg0
} mY"7/dw<v
8 A>OQR
publicvoid save(finalObject entity){ )DgXsT
getHibernateTemplate().save(entity); 1G>Ud6(3<
} %'Cj~An
nu0pzq\6
publicvoid persist(finalObject entity){ G+zhL6]F
getHibernateTemplate().save(entity); 8y
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} }]x \ `}o
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publicvoid update(finalObject entity){ HpnF,4A>
getHibernateTemplate().update(entity); [LYO'-g^F#
} F%w!I 9
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publicvoid delete(finalObject entity){ s<I)THC
getHibernateTemplate().delete(entity); Nk'<*;e
} 4MgN
OX_y"]utU
publicObject load(finalClass entity, +_5*4>MC
^^a6 (b
finalSerializable id){ .5|[gBK
return getHibernateTemplate().load ,PeR}E;c
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(entity, id); thjr1y.e
} -S sgW
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publicObject get(finalClass entity, qG9a!sj
)lG}B U.
finalSerializable id){ UG2+Y']
return getHibernateTemplate().get yE:y[k0E
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(entity, id); y=Y k$:-y
} Zxebv#4
:?M_U;;z2+
publicList findAll(finalClass entity){ DQG%`-J
return getHibernateTemplate().find("from GcV/_Y
qc8Ge\3s
" + entity.getName()); x3+
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} M':-f3aT%
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publicList findByNamedQuery(finalString `B%%2p&
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namedQuery){ wm5&5F4:
return getHibernateTemplate I}`pY3
R@c] )\^]
().findByNamedQuery(namedQuery); )OI}IWDl
} YVIE v
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publicList findByNamedQuery(finalString query, (0{Dn5MH
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finalObject parameter){ 'uu*DgEr
return getHibernateTemplate ]IuZ T
,6^<Vg
().findByNamedQuery(query, parameter); `OW'AS |
} Rhc:szDU
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publicList findByNamedQuery(finalString query, cv'8_3
*zdD4I=
finalObject[] parameters){ 4C;;V m4~
return getHibernateTemplate 2S8;=x}/
<cTX;&0=
().findByNamedQuery(query, parameters); i}m'#b
} d{fd5jv;
}&0LoW/
publicList find(finalString query){ RY;V@\pRY+
return getHibernateTemplate().find +hRy{Ps/
2E*=EjGV
(query); 8m+~HSIR
}
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publicList find(finalString query, finalObject mP)bOAU
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parameter){ Wl| i$L)7
return getHibernateTemplate().find aL(G0@(
j4XVk@'OX
(query, parameter); 64'2ICf#m
} O=%Ht-kOc
bxa>:71
public PaginationSupport findPageByCriteria :<g0Ho?e
=%U&$d|@G
(final DetachedCriteria detachedCriteria){ "51/,D
return findPageByCriteria 6ALjM-t=V
GCl
*x:
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Q>5f@aN
} $%EX~$=m]-
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public PaginationSupport findPageByCriteria @Ou
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<X*oW ".
(final DetachedCriteria detachedCriteria, finalint & AK\Pw)
]!ai?z%cK#
startIndex){ %{
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return findPageByCriteria h1~h&F?
%bw+>:Tr
(detachedCriteria, PaginationSupport.PAGESIZE, [{Wo:c9Qq1
6FDj :~
startIndex); "](Q2
} jf)cDj2
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public PaginationSupport findPageByCriteria ';R]`vWFe
QGN+f)
(final DetachedCriteria detachedCriteria, finalint 2TGND-(j
x-i,v"8
pageSize, S(.J
finalint startIndex){ vjX,7NY?
return(PaginationSupport) P5my]4|x
#M!u';bZ
getHibernateTemplate().execute(new HibernateCallback(){ %oiF} >
publicObject doInHibernate oG)T>L[&
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(Session session)throws HibernateException { / =9Y(v
Criteria criteria = .u mqyU~
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detachedCriteria.getExecutableCriteria(session); <lzC|>BG
int totalCount = OV{v6,>O
lITd{E,+r
((Integer) criteria.setProjection(Projections.rowCount w10~IP
sqhMnDn[
()).uniqueResult()).intValue(); A.*e8a/6X
criteria.setProjection Rxdj}xy
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(null); tQ@7cjq8bA
List items = e
( ]]
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criteria.setFirstResult(startIndex).setMaxResults z#gebr~_\
{N]WVp*R
(pageSize).list(); :?~)P!/xl5
PaginationSupport ps = 8(`e\)%l0
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new PaginationSupport(items, totalCount, pageSize, ?Tc|3U
'=nmdqP
startIndex); zWo
return ps; @7}XBg[pI
} oI#TjF
}, true); +788aK,{#
} }@LIb<Y
z#G\D5yX[*
public List findAllByCriteria(final xD*Zcw(vj~
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DetachedCriteria detachedCriteria){ E 14DZ
return(List) getHibernateTemplate zwUC
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n
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().execute(new HibernateCallback(){ ZC2aIJ
publicObject doInHibernate :.=:N%3[
y9mV6.r
(Session session)throws HibernateException { @~vg=(ic(
Criteria criteria = 2{RRaUoRb
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detachedCriteria.getExecutableCriteria(session); OybmyGHY
return criteria.list(); e!0xh
} 2MB>NM<xO
}, true); ajkV"~w',|
} Q"s6HZ"YI
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public int getCountByCriteria(final xJ<RQCW$
I]n X6=j5
DetachedCriteria detachedCriteria){ a;dWM(;Kw
Integer count = (Integer) `'|6b5`2j
<Z t ]V`-
getHibernateTemplate().execute(new HibernateCallback(){ bq5ySy{8
publicObject doInHibernate <
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(Session session)throws HibernateException { )'jGf;du
Criteria criteria = BHp>(7,
] K&ca
detachedCriteria.getExecutableCriteria(session); 6Z1O:Bou
return `yq)
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criteria.setProjection(Projections.rowCount &LI q?
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()).uniqueResult(); gna!Q
} q=e;P;u
}, true); <zY#qFQ2
return count.intValue(); V|A.M-XLv4
} c61 1&
} xuHP4$<h3
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wx-&(f
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用户在web层构造查询条件detachedCriteria,和可选的 xBc$qjV
2.JrLBhN
startIndex,调用业务bean的相应findByCriteria方法,返回一个 %o/@0.w
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PaginationSupport的实例ps。 [Cd#<Te3
RPMz&/k
ps.getItems()得到已分页好的结果集 Xgh%2;:
ps.getIndexes()得到分页索引的数组 .+Q1h61$T
ps.getTotalCount()得到总结果数 p]X+#I<
ps.getStartIndex()当前分页索引 D*46,>Tv
ps.getNextIndex()下一页索引 ~{g/
ps.getPreviousIndex()上一页索引 %;]/Z%!
m; =S]3P*
c>c3qjWY/
i:N-Q)<Q*)
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 *fd:(dN|
?r]0 %W^
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 )w}'kih
S&=@Hj-
一下代码重构了。 ZH=Bm^
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我把原本我的做法也提供出来供大家讨论吧: J7wwM'\
r_ m|?U
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首先,为了实现分页查询,我封装了一个Page类: W@GU;Nr
java代码: .0>bnw
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/*Created on 2005-4-14*/ b* n#XTV
package org.flyware.util.page; H9_>a->
)~
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/** Eb5>c/(
* @author Joa 4`5W] J]6
* ZHwN3
*/ 3>5gh8!-
publicclass Page { J#w=Z>oz <
WSF$xC/~
/** imply if the page has previous page */ k,OxGG
privateboolean hasPrePage; \\Zsxya1
U1yspHiZ
/** imply if the page has next page */ ho#<?rh_
privateboolean hasNextPage; rWJRoGk/
yq2AZ@}"
/** the number of every page */ we}5'bS>
privateint everyPage; Z[RifqaBby
pi;fu
/** the total page number */ 4ke.p<dG
privateint totalPage; a~VW?wq
<vs*aFq
/** the number of current page */ S"+#=C
privateint currentPage; =%}(Dvjv
$+{o*
/** the begin index of the records by the current 4*n1Xu7^x
L`:V]p
query */ >)[W7h
privateint beginIndex;
3<Z@!ft8
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HWL? doM
/** The default constructor */ 0|hOoO]?q&
public Page(){ v-F|#4Q=ut
D!)h92CIDm
} SoCN.J30
Efd@\m:~>
/** construct the page by everyPage I?q-
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* @param everyPage E-9>lb
* */ ~T._v;IT
public Page(int everyPage){ H11@ DQ6
this.everyPage = everyPage; I#F,
Mb>:
} Q&&=:97d
Zic:d-Q47
/** The whole constructor */ {poTA+i
public Page(boolean hasPrePage, boolean hasNextPage, j9%vw.3b
H?=[9?1wI5
L]X Lv9J0
int everyPage, int totalPage, ][\ uH|
int currentPage, int beginIndex){ Nhjz~S<o
this.hasPrePage = hasPrePage; VzM (u_)
this.hasNextPage = hasNextPage; L'a s^Od
this.everyPage = everyPage; je:J`4k$
this.totalPage = totalPage; |jWA >S
this.currentPage = currentPage; &`"uKO]
this.beginIndex = beginIndex; =(<7o_gJ
} @71y:)W<
>
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/** dDYor-g>
* @return sWq}/!@&
* Returns the beginIndex. -|czhO)R
*/ 3=Xvl 58k
publicint getBeginIndex(){ nwDW<J{f|U
return beginIndex; Nw1 .x
} *z'Rl'j9[
hz2f7g
/** 4l{La}Aj
* @param beginIndex fhHTp_u)2
* The beginIndex to set. Yk7^?W
*/ =lh&oPc1
publicvoid setBeginIndex(int beginIndex){ JS >"j d#
this.beginIndex = beginIndex; ~W gO{@Mw
} r_V^sX
Ys5Iqj=mp
/** gF M~M(
* @return >ZAn2s
* Returns the currentPage. {mHxlG)
*/ "W}+~Sn
publicint getCurrentPage(){ h5; +5B}D
return currentPage; ?`SBGN;
} y0t-e
x}7Xd P.2$
/** 0w$1Yx~C
* @param currentPage %A@U7gqc
* The currentPage to set. FxX nX
*/ ]`@<I'?,X
publicvoid setCurrentPage(int currentPage){ ehX4[j6
this.currentPage = currentPage; KXo[;Db)k
} {*Qx^e`h$.
S.fb[gI]
/** i+Xb3+R
* @return jdD`C`w|,
* Returns the everyPage. |y]8gL^
*/ 7YU}-gi
publicint getEveryPage(){ *pGbcBQ
return everyPage; y(r(q
} ~HX'8\5
aFy'6c}
/** ]@msjz'
* @param everyPage p#dYNed]'
* The everyPage to set. ^ s/f.#'
*/ 0^MRPE|f5
publicvoid setEveryPage(int everyPage){ M`G#cEc
this.everyPage = everyPage; 74~%4
} Xu[A,6
o l+*Oe
/** KlRIJOS
* @return 4Cf.%f9@
* Returns the hasNextPage. s9?H#^Y5u
*/ \z=!It]f.
publicboolean getHasNextPage(){ ,NU`aG-
return hasNextPage; *i7|~q/u
} K&iU+
R?kyJ4S
/** Qb1hk*$=
* @param hasNextPage xNxSgvco,
* The hasNextPage to set. Z
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7N
*/ $,7Yo
nc
publicvoid setHasNextPage(boolean hasNextPage){ /.@"wAw:
this.hasNextPage = hasNextPage; TC._kAm
} ;[j)g,7{
]A:G>K
/** 5SHZRF(. 2
* @return 5q.)K
f+
* Returns the hasPrePage. zAd%dbU|
*/ xR5zm%\
publicboolean getHasPrePage(){ G+Zm
return hasPrePage; k!wEPi]
} ~@VyJT%
1:q5h*
/** ~0gHh
* @param hasPrePage e:WKb9nT
* The hasPrePage to set. Ne2eBmY}(
*/ kCU(Hi`Q
publicvoid setHasPrePage(boolean hasPrePage){ :.fm LL
this.hasPrePage = hasPrePage; xAAwH@ +
} USyOHHPW@
UJQGwTA W
/** ;XGO@*V5T
* @return Returns the totalPage. lyyRyFfQ
* )Es|EPCx!
*/ sxU
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publicint getTotalPage(){ XXPpj< c
return totalPage; (wZ/I(4
} S8)6@ECC
Jm*wlN
[>
/** rTtxmw0
* @param totalPage B["C~aF
* The totalPage to set. 2G BE=T
*/ .OSFLY#[?
publicvoid setTotalPage(int totalPage){ IX 2 dic'
this.totalPage = totalPage; =$Sd2UD
} Q)\4 .d
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} xU;;@9X
IpI|G!Y,
qv$m5CJvK
]F*fQNcjy
6{TUs>~
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 B)u*c]<qU
@ZGD'+zd?
个PageUtil,负责对Page对象进行构造: uBfSS\SX|
java代码: mvt%3zCB!
v,A8Mk2s#
PFPZ]XI%F
/*Created on 2005-4-14*/ c R6:AGr
package org.flyware.util.page; 1gDsL
AqucP@
import org.apache.commons.logging.Log; [$%O-_x
import org.apache.commons.logging.LogFactory; ,ftKRq
#hF(`oX}4K
/** oD&axNk
* @author Joa 0}I aWd^4
* (E]q>'X
*/ ~~X-$rtU
publicclass PageUtil { i5jsM\1j
2N[/Cc2Tg/
privatestaticfinal Log logger = LogFactory.getLog xv>]e <":
XMw*4j2E
(PageUtil.class); >K-S&Y
qv.s-@l8
/** p5\B0G<m
* Use the origin page to create a new page )lrmP(C*.a
* @param page wOs t).
* @param totalRecords I7e.pm
* @return .FpeVjR''
*/ ?I332,,q
publicstatic Page createPage(Page page, int 8t
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bE>"DPq
totalRecords){ :pvJpu$]
return createPage(page.getEveryPage(), 9B?-&t
.I
nDyKt
page.getCurrentPage(), totalRecords); ;30SnR/
} nb_$g@ 03
VQwF9Iq]`
/** Z=j6c"
* the basic page utils not including exception o3=pxU*
~"nF$DB
handler &Na,D7A:3I
* @param everyPage r: M>/Z/
* @param currentPage 2nkymEPu
* @param totalRecords
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* @return page 85Red~-M
*/ ,v$Q:n|
publicstatic Page createPage(int everyPage, int r6gfxW5
&ws^Dm]R
currentPage, int totalRecords){ LeaJ).Maw
everyPage = getEveryPage(everyPage); FDCc?>,o
currentPage = getCurrentPage(currentPage); On-zbE
int beginIndex = getBeginIndex(everyPage, X_aC$_b
Yh2[
nF_
currentPage); G[$g-NU+
int totalPage = getTotalPage(everyPage, v,^W& W.
Z|$M 9E
totalRecords); Zi=/w
boolean hasNextPage = hasNextPage(currentPage, 1U6z2i+y
_kXq0~
totalPage); @jY=b<
boolean hasPrePage = hasPrePage(currentPage); h'ik19
v8f1o$R
returnnew Page(hasPrePage, hasNextPage, _=-B%m
everyPage, totalPage, Cd2A&RB
currentPage, R,dbq4xkl
9wbj}tN\z
beginIndex); TQ5*z,CkS
} ,8G6q_ud
T7~H|%
privatestaticint getEveryPage(int everyPage){ @L?KcGD
return everyPage == 0 ? 10 : everyPage; wl7 (|\-
} ApNS0
3t9Weo)
privatestaticint getCurrentPage(int currentPage){ <\ EJ:
return currentPage == 0 ? 1 : currentPage; !
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} N> xdX5
j9xu21'!%
privatestaticint getBeginIndex(int everyPage, int Yhte&,D"
n#^ii/H
currentPage){ e2qSU[
return(currentPage - 1) * everyPage; A<''x'\/
} gy>B
5ie
5.d[C/pRw
privatestaticint getTotalPage(int everyPage, int sOVU>tb\'
L Q0e@5
totalRecords){ L Iz<fB
int totalPage = 0; );;UA6CD
T:Nc^QP|tm
if(totalRecords % everyPage == 0) z3I
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totalPage = totalRecords / everyPage; /V
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else uH]oHh!}j
totalPage = totalRecords / everyPage + 1 ; ny1;]_X_
pZz\o
return totalPage; [ylRq7^e
} 7YFEyX10d
\{v e6`7Rn
privatestaticboolean hasPrePage(int currentPage){ #MFIsx)r
return currentPage == 1 ? false : true; =M=v;
,I-
} 8W Etm}
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privatestaticboolean hasNextPage(int currentPage, 7-gT:
s }Ql9
int totalPage){ YD;G+"n?T
return currentPage == totalPage || totalPage == Ad&VOh+0
$*;`$5.x^
0 ? false : true; "+E\os72|
} P ; h8
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?4^ 0xGyE
} V503
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TV=K3F5)M
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ocu,qL)W
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 m?kyAW'|
[ ou$*
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 y @S_CB47
iX[g
做法如下: MU%7'J :_
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 v7n@CWnN
"}V_.I*+
的信息,和一个结果集List: IC?(F]$%>
java代码: $<yhEvv
.5uqc.i"f
+Qf}&D_
/*Created on 2005-6-13*/ H@1}_d
package com.adt.bo; `Qjs{H
/3&MUB*z&y
import java.util.List; 0` .5gxm
L0oVXmlr
import org.flyware.util.page.Page; |Ve,Y
L7hRFf-o
/** G[1\5dK*uR
* @author Joa ?}uuTNLl)
*/ tva=DS
publicclass Result { NBHpM}1xtU
C~R
?iZ.&U
private Page page; f,4erTBH
. P+Qu
private List content; MqJ5|C.q
t1]/Bw`j/
/** Vd(n2JMtG
* The default constructor z:4_f:70
*/ {
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public Result(){ 'ZB^=T
super(); ()48> ||
} q
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8CZ%-}-%$
/** k/D{&(F ~
* The constructor using fields *~>p;*
* X'-Yz7J?o
* @param page !|up"T I
* @param content 0EF~Ouef
*/ :eSsqt9]9
public Result(Page page, List content){ &7oL2Wf
this.page = page; 7[w<v(Rc
this.content = content; vFB^h1k~.M
} ZP5 !O[Ut
JJM<ywPGp
/** 2 rr=FJ
* @return Returns the content. [orL.D]
*/ [iEz?1.,
publicList getContent(){ }zx
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return content; VX&PkGi?o
} _bi)d201
SI=u-'%
/** ddyX+.LMk
* @return Returns the page. PO?_i>mA
*/
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public Page getPage(){ !Av9?Q:
return page; U(9_&sL
} ^:]$m;v]
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o; `
/** h='F,r5#2
* @param content [ r8 ZAS
* The content to set. U!`iKy-
*/ B+snHabS6
public void setContent(List content){ !TJ,:c]4{!
this.content = content; C!a1.&HHZ7
} XS">`9o!
".tL+A[
/** Ff%V1BH[
* @param page -X~mW
* The page to set. Cf3!Ud
*/ qS2Nk.e]o
publicvoid setPage(Page page){ Z sTtSM\Ac
this.page = page; +)iMJ]>
} (rd
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} M{Z
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m$kQbPlatN
lOk8VlH<h
9MYk5q.X:
:t]HY2
2. 编写业务逻辑接口,并实现它(UserManager, hU8Y&R)=9
{PcJuRTHB
UserManagerImpl) U~N7\Pa4
java代码: <"J]u@|
dy&UF,l6
k(l2`I4V
/*Created on 2005-7-15*/ O,%,dtD[a
package com.adt.service; 8~]D!c8; a
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import net.sf.hibernate.HibernateException; AQg|lKv
m|;(0
rft
import org.flyware.util.page.Page; -juG[zn
u]};QR
import com.adt.bo.Result; q8?kBKP
pW(rNAJ!
/** lGl'A}]#$
* @author Joa &~
y)b`r
*/ ~0a5
publicinterface UserManager { 6(Pan%
`X6JZxGyd
public Result listUser(Page page)throws {P]C>
W(`QbNJ
HibernateException; GWnIy6TH l
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} yZ|"qP1
.h7s.p?
o)AwM"
s|]g@czan
DAB9-[y+
java代码: K>@yk9)vi
HU i?\4
/Vn>(;lo
/*Created on 2005-7-15*/ !Qe;oMqy}
package com.adt.service.impl; Nr4:Gih
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import java.util.List; lmvp,BzC
h'):/}JPl
import net.sf.hibernate.HibernateException; 2Wz8E2.
'4[=*!hs!
import org.flyware.util.page.Page; * x/!i^
import org.flyware.util.page.PageUtil; 4Z( #;9f
:$MOdL[ir
import com.adt.bo.Result; I6W`yh`I)
import com.adt.dao.UserDAO; zTF{ g+
import com.adt.exception.ObjectNotFoundException; O?JJE8~']
import com.adt.service.UserManager; =|S%Rzsk
3/kT'r
/** IOcQI:4.`
* @author Joa 8Xotly
*/ QF#w$%7
publicclass UserManagerImpl implements UserManager { 9=%zd z2_S
BBB@M
private UserDAO userDAO; vk&
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4wl1hp>,
/** /\I6j;$z
* @param userDAO The userDAO to set. G*fo9eu5$
*/ Wwq:\C
publicvoid setUserDAO(UserDAO userDAO){ z)qYW6o%
this.userDAO = userDAO; /kW Z 8Z
} mgq!)
$KiCs]I+
/* (non-Javadoc) Oj5UG*
* @see com.adt.service.UserManager#listUser &O&HczO
0
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(org.flyware.util.page.Page) Ts5)r(
*/ XA>W>|
public Result listUser(Page page)throws &S,D;uhF
=ejj@c
HibernateException, ObjectNotFoundException { K,E/.Qe\C
int totalRecords = userDAO.getUserCount(); A`c%p7Z%
if(totalRecords == 0) KP&+fDa
throw new ObjectNotFoundException { mi}3/
,=:K&5mCv
("userNotExist"); ]pax,|+$C
page = PageUtil.createPage(page, totalRecords); ef5)z}B
List users = userDAO.getUserByPage(page); iC
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returnnew Result(page, users); :Ha/^cC/3
} &L;ocd$
=3e7n2N)
} "O&93#8
Q`ua9oIJ=
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{"y/;x/
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 _R4}\3}!
9%!h/m>rW
询,接下来编写UserDAO的代码: 7L{1S
v
3. UserDAO 和 UserDAOImpl: `ONjEl
java代码: m>@hh#kBg
*o6}>;
rf.pT+g.P
/*Created on 2005-7-15*/ :t}\%%EbmE
package com.adt.dao; b\k]Jx
)pB#7aEw
import java.util.List; jEc_!Q
YG "Ta|@5
import org.flyware.util.page.Page; L:R4&|E/t
{f/qI`
import net.sf.hibernate.HibernateException; IGdiIhH~2
^|]&"OaB
Z
/** BQ@7^E[
* @author Joa }u Y2-l
*/ 6K/RO)
publicinterface UserDAO extends BaseDAO { aAo|3KCs
WJShN~ E
publicList getUserByName(String name)throws {keZ_2
1|bXIY.J*
HibernateException; +#}GmUwPG$
d>NGCe
publicint getUserCount()throws HibernateException; 7FB?t<x
B VBn.ut
publicList getUserByPage(Page page)throws 8:ubtB
Kb.qv)6i*
HibernateException; D!<F^mtl
gD,&TW
} ?YhDjQs
L.Y3/H_
JzyCeM =
,UNb#=it
#lYyL`B+~
java代码: 6EqA Y`y
TBj 2(Z
X8Z?G,[H
/*Created on 2005-7-15*/ cG|fau<G
package com.adt.dao.impl; U( YAI%O
+&GV-z~o
import java.util.List; Y-VDi.]W
]z'&oz
import org.flyware.util.page.Page; =~D? K9o
KkvcZs'4m
import net.sf.hibernate.HibernateException; L4By5)
import net.sf.hibernate.Query; o3J#hQrl
dbp\tWaW
import com.adt.dao.UserDAO; :6n#y-9^1
E)"19l|}B
/** k[6J;/
* @author Joa B}e/MlX3M
*/ nzq
public class UserDAOImpl extends BaseDAOHibernateImpl rTPgHK]?l
~?ab_CY
implements UserDAO { ^7gGtz2
t^s&1#iC
/* (non-Javadoc) &i#$ia r
* @see com.adt.dao.UserDAO#getUserByName _y@28t
-IPo/?}
(java.lang.String) <r%K i`u(p
*/ +;N]34>S7
publicList getUserByName(String name)throws LGP"S5V
r$7.
HibernateException { &D,Iwq
String querySentence = "FROM user in class AIF?>wgq
{ 3G
com.adt.po.User WHERE user.name=:name"; bLqy7S9x
Query query = getSession().createQuery agIqca;
DUp`zW;B
(querySentence); p{f R$-d
query.setParameter("name", name); HJL! ;i
return query.list(); ,OE&e*1
} tKbxC>w
|'^s3i&w
/* (non-Javadoc) %iyc1]w{
* @see com.adt.dao.UserDAO#getUserCount() 1\}vU
*/ DfXkLOGik
publicint getUserCount()throws HibernateException { 5`;SI36"
int count = 0; 4TtC~#D:
String querySentence = "SELECT count(*) FROM f|[7LIdh-
(gt\R}
user in class com.adt.po.User"; Fmk:[hMw
Query query = getSession().createQuery 'aSsyD!?<
[xS7ae
(querySentence); s~M4. 06P
count = ((Integer)query.iterate().next mm/\\my
rrD6x>
()).intValue(); TdhfX {nk
return count; uD\R3cY
} crmQn ^4\
~_ THvx1
/* (non-Javadoc) M2$/x`\-~
* @see com.adt.dao.UserDAO#getUserByPage u$ts>Q;5
)aS:h}zn
(org.flyware.util.page.Page) c_/BS n
*/ Y}~sTuWU
publicList getUserByPage(Page page)throws >xWS>
7B?Y.B
HibernateException { 7)?C+=,0
String querySentence = "FROM user in class H2X_WSwm
@0 +\:F
com.adt.po.User"; P1#g{f
Query query = getSession().createQuery LdUz;sb
G% F#I
(querySentence); B=SA
+{o
query.setFirstResult(page.getBeginIndex()) corm'AJ/
.setMaxResults(page.getEveryPage()); Ly=.
return query.list(); A95f!a
} ~q>jXi
:;$MUOps
} E-A9lJWr
inu.U[.
HQ-[k$d
W4
aDS:82GMQ
lrrTeE*
至此,一个完整的分页程序完成。前台的只需要调用 l@`k:?
xP8/1wd.
userManager.listUser(page)即可得到一个Page对象和结果集对象 5'!fi]Z
O,$*`RZpx
的综合体,而传入的参数page对象则可以由前台传入,如果用 fB2ILRc
FZ*"^=)`G
webwork,甚至可以直接在配置文件中指定。 " ityx?
l\_!oa~
下面给出一个webwork调用示例: R|?n
java代码: B`SX3,3
snbXAx1L
SSe;&Jk2d
/*Created on 2005-6-17*/ +y|
B"}x
package com.adt.action.user; Et6j6gmif
Ey@^gHku\
import java.util.List; h#1:ypA6l
2> a&m>
import org.apache.commons.logging.Log; {O+T`;=)L
import org.apache.commons.logging.LogFactory; Laj/~Ru6
import org.flyware.util.page.Page; L*0YOE%=]
[Rj4=qq=
import com.adt.bo.Result; VL#:oyWA
import com.adt.service.UserService; z,Xj$wl
import com.opensymphony.xwork.Action; N"9^A^w8k
tI^91I
/** 8vx
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* @author Joa l;-2hZ
*/ Tzd#!Lvm:,
publicclass ListUser implementsAction{ ~-"CU:$o
{$S"Sj
privatestaticfinal Log logger = LogFactory.getLog r^k+D<k[7
=Jp:dM*
(ListUser.class); [REH*_
B:>:$LIL
private UserService userService; QPuc{NcB>
=svFw&q"
private Page page; JMAdsg/
%[XP}L$
privateList users; &XNt/bK-?
FQek+[ox
/* :k9T`Aa]
* (non-Javadoc) |AvPg
* .7.G}z1
* @see com.opensymphony.xwork.Action#execute() k$=L&id
*/ yp~z-aRa
publicString execute()throwsException{ ~n -N
Result result = userService.listUser(page); gmp@ TY=:L
page = result.getPage(); @tT`s^e
users = result.getContent(); O%%Q./oh
return SUCCESS; G[}v?RLI
} mJ%^`mrI
<*vR_?!
/** ^*jwe^
* @return Returns the page. $H*8H`
*/ u?V}pYX
public Page getPage(){ ;X}2S!7Ko
return page; 1_7p`Gxt[/
} 2K4Xu9-i:b
#x 6/"Y2
/** SY9 5s
* @return Returns the users. fAh|43Y*a
*/ olv&K(-ccI
publicList getUsers(){ iKq_s5|sW
return users; (ot,CpI(I
} ",apO
V;^-EWNj
/** +<