Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 kqJ\kd
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 z)$X/v
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 78't"2>
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 6{/HNEI*1
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。 "?E>rWz
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分页支持类: 5AV5`<r.
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java代码: ~4YU
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package com.javaeye.common.util; <4!SQgL
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import java.util.List; JY4sB8
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publicclass PaginationSupport { ;E? Z<3{
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publicfinalstaticint PAGESIZE = 30; k.b->U
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privateint pageSize = PAGESIZE; \%fl`+`
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privateList items; "/v{B?~%!
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2\
privateint totalCount; *z-Mr~V
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privateint[] indexes = newint[0]; -X#Zn>#
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privateint startIndex = 0; {ir8n731p
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public PaginationSupport(List items, int >U/m/H'
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totalCount){ )%D2JC
setPageSize(PAGESIZE); @SH%l]
setTotalCount(totalCount); x^_(gve:
setItems(items); JVO,@~~
setStartIndex(0); 7`,A]":;
} 7}+U;0,)
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public PaginationSupport(List items, int 1t"
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totalCount, int startIndex){ o' U::
setPageSize(PAGESIZE); JWHKa=-H
setTotalCount(totalCount); b65V*Vbj
setItems(items); NE Br)~
setStartIndex(startIndex); ROZOX$XM
} t;ZA}>/
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public PaginationSupport(List items, int SM3Q29XIw
{<f_,Nlc
totalCount, int pageSize, int startIndex){ S%ULGX:@ga
setPageSize(pageSize); ESdjDg$[u
setTotalCount(totalCount); .GG6wL<$?
setItems(items); )m .KV5K!
setStartIndex(startIndex); Rlvb@aXgy
} g8<Ja (J
.QRa{l_)
publicList getItems(){ &%."$rC/0b
return items; {%Mt-Gm'd
} d51.Tbt#%7
6$#p}nE
publicvoid setItems(List items){ <3aiS?i.h
this.items = items; f=0U&~
} ` drds
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publicint getPageSize(){ -[\+~aDH,
return pageSize; DIx!Sw7EC
} i"eUacBz/-
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publicvoid setPageSize(int pageSize){ j<+QGd%
this.pageSize = pageSize; &DnX6%2
} RLuA^ONI
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publicint getTotalCount(){ Oj6PmUK4
return totalCount; <5oG[1j
} ;|(_;d
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publicvoid setTotalCount(int totalCount){ >z&|<H%
if(totalCount > 0){ ,^]yU?eU
this.totalCount = totalCount; >fCz,.L
int count = totalCount / N_AAh D
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pageSize; 0Q\6GCzN\
if(totalCount % pageSize > 0) \[m{ &%^G
count++; FdT@}
indexes = newint[count]; $LxfdSa
for(int i = 0; i < count; i++){ ;MD6iBD
indexes = pageSize * GEJEhwO;H
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i;
9
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} .c#G0t<i[
}else{ TL%2?'G
this.totalCount = 0; DEmU},<S
} <B,z)c
} g\%vkK&I
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publicint[] getIndexes(){ eUa2"=M
return indexes; Yv="oG!xL
} d9'gH#f?
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publicvoid setIndexes(int[] indexes){ P2lDi!q|
this.indexes = indexes; ~0S_S +e
} sj@B0R=Qo
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publicint getStartIndex(){ Z_Tu*
F
return startIndex; gQXB=ywF
} #=>t6B4af
XYeuYLut
publicvoid setStartIndex(int startIndex){ PjL"7^Q&
if(totalCount <= 0) @qC](5|TQ
this.startIndex = 0; ;xp^FKP
elseif(startIndex >= totalCount) +mc0:e{WF
this.startIndex = indexes 1trk
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[indexes.length - 1]; $@H]0<3,
elseif(startIndex < 0) Qw&It
this.startIndex = 0; q|Oz
else{ X?p.U
this.startIndex = indexes FQc8j:'
u ##.t
[startIndex / pageSize]; [QC|Kd^#
} %XIPPEHU
} ;QVX'?
i,77F !
publicint getNextIndex(){ hrLPyV:
int nextIndex = getStartIndex() + 9eA2v{!S
U
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pageSize; I/F3%'O
if(nextIndex >= totalCount) dd $}FlT
return getStartIndex(); Vn4y^_H
else =!@5!
return nextIndex; gO{XD.s
} KJ/
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HY
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publicint getPreviousIndex(){ =LP,+z
int previousIndex = getStartIndex() - c:%ll&Xtn
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pageSize; /hx|KC&:e
if(previousIndex < 0) '?WKKYD7N
return0; jHP6d =
else +7HM7cw
return previousIndex; +W{ELdup%q
} Het5{Yb.
h[%t7qo=
} 3%"r%:fQB/
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抽象业务类 jJ(()EJ
java代码: !R{C
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/** (T0%oina
* Created on 2005-7-12 bZf18lvij:
*/ rKK{*%n
package com.javaeye.common.business; ,-55*Rb i
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import java.io.Serializable; nhbCk6Y5LZ
import java.util.List; WyO7,Qr\
a{oG[e
import org.hibernate.Criteria; 38I .1p9
import org.hibernate.HibernateException; {6V;$KqH6
import org.hibernate.Session; IW Ro$Yu
import org.hibernate.criterion.DetachedCriteria; )QeXA)
import org.hibernate.criterion.Projections; SCXH{8SS
import &mG1V
Xm#E9 9
org.springframework.orm.hibernate3.HibernateCallback; 7Nw}
}
import v>e%5[F
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org.springframework.orm.hibernate3.support.HibernateDaoS A7|CG[wZ
BCrX>Pp}r
upport; 9|;"+jlt
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import com.javaeye.common.util.PaginationSupport; QT!!KTf
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public abstract class AbstractManager extends J\WUBt-M
@|N'V"*MT
HibernateDaoSupport { #u<^
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privateboolean cacheQueries = false; 2}NWFM3C
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privateString queryCacheRegion; V>8)1)dF
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publicvoid setCacheQueries(boolean 1;e"3x"
.<0s?Q
cacheQueries){ @xO?SjH
this.cacheQueries = cacheQueries; 1$Jria5n
} ,KM-DCwcG
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publicvoid setQueryCacheRegion(String AK7IPftlH
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queryCacheRegion){ GT -(r+u
this.queryCacheRegion = ?Re6oLm<B
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queryCacheRegion; ?u*gKI
} U',.'"m
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publicvoid save(finalObject entity){ mKsTA;
getHibernateTemplate().save(entity); B4/0t:^I
} ?iX1;c9
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publicvoid persist(finalObject entity){ SO~]aFoYt
getHibernateTemplate().save(entity); t *8k3"
} x_C#ALq9
)]\?Yyg]
publicvoid update(finalObject entity){ V_>)m3zsL
getHibernateTemplate().update(entity);
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} 0%K/gd#S<
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publicvoid delete(finalObject entity){ ~If{`zWoC
getHibernateTemplate().delete(entity); u-31$z<<5}
} $>72 g.B
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publicObject load(finalClass entity, j.'Rm%@u
(c'=jJX
finalSerializable id){ `|["{j}^
return getHibernateTemplate().load _fVC\18T
e)(m0m\
(entity, id); B/iRR2h
} ?8j#gYx2
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publicObject get(finalClass entity, %(9BWO
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finalSerializable id){ SP&Y|I$:
return getHibernateTemplate().get wR x5` @
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(entity, id); Z5oX "Yx
} .U66Uet>RX
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publicList findAll(finalClass entity){ ZL0':7
return getHibernateTemplate().find("from I T.'`!T
E(0(q#n
" + entity.getName()); OG M9e!
} eH*u,/
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publicList findByNamedQuery(finalString :;wb{q$O
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namedQuery){ z_Nw%V4kr
return getHibernateTemplate 3#IU^6l:1S
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().findByNamedQuery(namedQuery); 0Hs\q!5Q
} DeMF<)#
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publicList findByNamedQuery(finalString query, ) <lpI';T
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finalObject parameter){ :HJ@/s!J
return getHibernateTemplate xnyp'O8yk
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kMz
().findByNamedQuery(query, parameter); Kn#3^>D
} Esc*+}ck
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publicList findByNamedQuery(finalString query, !'-|]xx(
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finalObject[] parameters){ $U uSrX&
return getHibernateTemplate ]^='aQ
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().findByNamedQuery(query, parameters); *ybwlLg
} OMr &f8
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publicList find(finalString query){ q=o"]
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return getHibernateTemplate().find Qx_K)
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(query); [n53eC
} if
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publicList find(finalString query, finalObject `&)khxT/
.] S{T
parameter){ 0@ -3U{Q
return getHibernateTemplate().find p'`SYEY@Z
JG2)-x;9
(query, parameter); C ?^si
} 7[V6@K!Al[
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public PaginationSupport findPageByCriteria ~[J&n-bJU
C$Y pk\p
(final DetachedCriteria detachedCriteria){ VTDp9s
return findPageByCriteria 5UFR^\e
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}u,uI
(detachedCriteria, PaginationSupport.PAGESIZE, 0); /r4QDwu
} aZe[Nos
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public PaginationSupport findPageByCriteria Qi_De
'@
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(final DetachedCriteria detachedCriteria, finalint IZ2c<B5&
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startIndex){ 6j]pJ]F6
return findPageByCriteria ty8\@l
>5i(U_`l
(detachedCriteria, PaginationSupport.PAGESIZE, c8o$WyO
}tH$/-qnJE
startIndex); J,8Wo6
} $X.X_
EW* 's(
public PaginationSupport findPageByCriteria PV2cZ/
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(final DetachedCriteria detachedCriteria, finalint :Sh>
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pageSize, 7p}.r
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finalint startIndex){ uZyR{~-C
return(PaginationSupport) VfJbexYT
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getHibernateTemplate().execute(new HibernateCallback(){ GC{)3)_ t
publicObject doInHibernate x<
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(Session session)throws HibernateException { lP@/x+6tg
Criteria criteria = +^St"GWY
{9 >jWNx
detachedCriteria.getExecutableCriteria(session); @K 8sNPK
int totalCount = @wWro?s'p
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((Integer) criteria.setProjection(Projections.rowCount Y.O/~ af
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()).uniqueResult()).intValue(); ZMSP8(V
criteria.setProjection 0]dL;~0y.
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(null); kf3yJP/
List items = W$x'+t5H
H3=U|wr|
criteria.setFirstResult(startIndex).setMaxResults S`LS/)
@v1f)(N
(pageSize).list(); |[k/%
PaginationSupport ps = A7~~{9
#+2|ZfCn%
new PaginationSupport(items, totalCount, pageSize, wvAXt*R
>Q0HqOq
startIndex);
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return ps; 3>[_2}l
} Z4\$h1tl
}, true); *$ZLu jy7
} L0_qHLY
yNk9KK )
public List findAllByCriteria(final .Dw^'p>
=K<8X!xUW
DetachedCriteria detachedCriteria){ J$)lYSNE
return(List) getHibernateTemplate qb+vptg@I
Fe(qf>E
().execute(new HibernateCallback(){ 5feCA ,v7
publicObject doInHibernate R3]Ra&h6N)
m6P!#=a:l<
(Session session)throws HibernateException { &n%
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Criteria criteria = `(|jm$Q
Bc{#ia
detachedCriteria.getExecutableCriteria(session); y//yLrs;
return criteria.list(); z6tH2Wxf
} MB,;HeP!
}, true); _v2K1 1
} Z8\c'xN
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public int getCountByCriteria(final C7ZU)MEUd/
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DetachedCriteria detachedCriteria){ e[t+pnRh
Integer count = (Integer) 6x*u S~'
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getHibernateTemplate().execute(new HibernateCallback(){ z}'*zB>
publicObject doInHibernate ER:)Fk>_
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(Session session)throws HibernateException { &e\A v.n@-
Criteria criteria = $7{V+>
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detachedCriteria.getExecutableCriteria(session); &lYZ=|6
return ~Co7 %e V
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criteria.setProjection(Projections.rowCount L0{ehpvM
gt5
()).uniqueResult(); b??k|q
} f`X#1w9
}, true); &xF 2!t`
return count.intValue(); F=C8U$'S
} !BHIp7p
} 7d0E9t;W
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用户在web层构造查询条件detachedCriteria,和可选的 pb~&gliW
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 N
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PaginationSupport的实例ps。 |q?I(b4 Q@
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ps.getItems()得到已分页好的结果集 PgZ~of&
ps.getIndexes()得到分页索引的数组 U!sv6=(y@
ps.getTotalCount()得到总结果数 1]r+$L3
ps.getStartIndex()当前分页索引 irNGURLm
ps.getNextIndex()下一页索引 s}Q%]W
ps.getPreviousIndex()上一页索引 dKcHj<'E/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 sa8Sy& X"
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 C[:Q?LE
v~:$]a8
一下代码重构了。 3\6UH
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我把原本我的做法也提供出来供大家讨论吧: #2c-@),
5-|fp(Ww_W
首先,为了实现分页查询,我封装了一个Page类: Qci<cVgP
java代码: FJ3Xeos4|
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/*Created on 2005-4-14*/ 5fS89?/?
package org.flyware.util.page; xUE 9%qO
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/** ]@bo; .
* @author Joa jcF/5u5e
* Sk@~}
*/ Fl GKy9k
publicclass Page { vkan+~H
fSdv%$;Hc
/** imply if the page has previous page */ b'fj
privateboolean hasPrePage; Y418k
eRllF `*
/** imply if the page has next page */ Qz;2RELz
privateboolean hasNextPage; )+[IR
K"1xtpy
/** the number of every page */ 5EDM?G
privateint everyPage; :0pxacD"!
Y3jb'S4(
/** the total page number */ DUiqt09`~
privateint totalPage; fL4F
~@`9l
=8 d`qS"
/** the number of current page */ ):C4"2l3
privateint currentPage; 5:SfPAx
.H+`]qLkL
/** the begin index of the records by the current 6/9 A' !4C
:NHh`@0F
query */ '3eP<earRP
privateint beginIndex; MId\dFu
u2'xM0nQ
>4=sEj
/** The default constructor */ <2w@5qL
public Page(){ BvpGP
ymybj
} !8ub3oj)
=!r9;L,?
/** construct the page by everyPage $@q)IK%FDL
* @param everyPage +\9Y;Ny
* */ 5B| iBS l
public Page(int everyPage){ Gs2.}lz
this.everyPage = everyPage; 0o[p<<c*
} cYdk,N
{U4BPKof
/** The whole constructor */ oQ@X}6B%S
public Page(boolean hasPrePage, boolean hasNextPage, q%#dx4z&
ciI;U/V
ZbCu -a{v
int everyPage, int totalPage, rixNz@p'%
int currentPage, int beginIndex){ ~q#UH'=%
this.hasPrePage = hasPrePage; zLuej'
this.hasNextPage = hasNextPage; @Y*ONnl
this.everyPage = everyPage; 3+"z
this.totalPage = totalPage; 3.B|uN
this.currentPage = currentPage; z=vfP%
this.beginIndex = beginIndex; d$g-u8
} \(jSkrrD
~h?zK1
/** oT$w14b
* @return N5[QQtQ
* Returns the beginIndex. G_=`&i"4
*/ SZH,I&8
publicint getBeginIndex(){ dNG>:p
return beginIndex; xlkEW&N&
} ^_KHw
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/** K=VYRY
* @param beginIndex VWd=7
* The beginIndex to set. r8+{HknB;
*/ ~j",ePl
publicvoid setBeginIndex(int beginIndex){ LnvC{#TFO
this.beginIndex = beginIndex; s$J0^8Q~i
} L~SM#?z:ue
HS]|s':
/** "zR+}
* @return f$9V_j-K+
* Returns the currentPage. (F~i
*/ +mE y7qM
publicint getCurrentPage(){ OT{wqNI
return currentPage; ;OTD1=
} ZffK];D
+j&4[;8P:
/** CHv~H.kh'
* @param currentPage z#GZvB/z)
* The currentPage to set. Hb=4k)-/]
*/ cD
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publicvoid setCurrentPage(int currentPage){ 0Z8K +,'!
this.currentPage = currentPage; n
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} dGf{d7 D
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/** )nJs9}( 0
* @return 5Y)*-JY1g
* Returns the everyPage. 6;9SU+/
*/ :CNWHF4$
publicint getEveryPage(){ ZY +NKb_
return everyPage; q5YgKz?IC
} f{AbCi
C^XJE1D.
/** #g\O*oYaw
* @param everyPage pJ"Wg@+
* The everyPage to set. ^tIs57!
*/ f"q='B9_T\
publicvoid setEveryPage(int everyPage){ QNJ )HNLp
this.everyPage = everyPage; q>X#Aaib
} ]6Kx0mW
+rfw)c'
/** a,x-akZWf
* @return F]@vmzr
* Returns the hasNextPage. _5EM <Ux
*/ W'eF
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publicboolean getHasNextPage(){ %fnL
return hasNextPage; \I1+J9Gl
} (eS4$$g
v1<3y~'f
/** M%5qx,JQY
* @param hasNextPage nAG2!2_8
* The hasNextPage to set. Zsc710_
*/ (e6JI]tz{
publicvoid setHasNextPage(boolean hasNextPage){ TZT i:\nS
this.hasNextPage = hasNextPage; i[sHPEml(5
} q+5g+9
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/** K[PH#dF5,x
* @return UUc{1"z{
* Returns the hasPrePage. R$k4}p
*/ _Je<_pl!D
publicboolean getHasPrePage(){ BSYJ2
return hasPrePage; &eKnLGKD
} 1[OCoj o<
w2_$>z
/** ~cQ./G4
* @param hasPrePage FM$XMD0=
* The hasPrePage to set. x;dyF_*;
*/ ?8X;F"Ba
publicvoid setHasPrePage(boolean hasPrePage){ NK;%c-r0v7
this.hasPrePage = hasPrePage; ~CCRs7V/L
} 1p=^I'#
MdmS
/** {.qeVE{
* @return Returns the totalPage. 5P-7"g ca
* fmrd 7*MW
*/ \/J>I1J
publicint getTotalPage(){ '!^5GSP3&
return totalPage; @(M-ZO!D
} {fFZ%$
s(jixAf
/** j\k|5="w-
* @param totalPage ;NQ9A &$)
* The totalPage to set. 9z6-HZG'~<
*/ u:JD
publicvoid setTotalPage(int totalPage){ T1 >xw4uo
this.totalPage = totalPage; ?XN=Er^
} 8'[g?
}5
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} gpDH_!K
_rt+OzZ*L
b5lZ| |W.
k=!lPIx
s:ig;zb
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 r0t4\d_&
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个PageUtil,负责对Page对象进行构造: 1=:=zyEEo
java代码: l{ <+V)
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/*Created on 2005-4-14*/ {2 l35K=
package org.flyware.util.page; 9oBK(Sf@^
1c8Nr&Jl
import org.apache.commons.logging.Log; E#}OIZ\S
import org.apache.commons.logging.LogFactory; #0>??]&r
nX%b@cOXj
/** .UX`@Q:Gp
* @author Joa =f0qih5.4
* C'$w*^me
*/ nMm4fns
publicclass PageUtil { 35=kZXwG+4
55Z)*JMv
privatestaticfinal Log logger = LogFactory.getLog 5"5!\Zo
4A0
,N8ja}
(PageUtil.class); San3^uX
QL/I/EgqC
/** %d?.v_Hu0
* Use the origin page to create a new page S;@nPzhc
* @param page vDI$
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* @param totalRecords t7GK\B8:
* @return BwOIdz%]OY
*/ 1.Kun !w
publicstatic Page createPage(Page page, int ayF+2(vch)
xb{G:v
totalRecords){ I<E~=
return createPage(page.getEveryPage(), (Yi1U~{:
rSu+zS7`X
page.getCurrentPage(), totalRecords); E$O-\)wY0
} -YvnX0j+
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/** >^Rkk{cc
* the basic page utils not including exception 5<64 C}fE3
w{F{7X$^
handler |ppG*ee
* @param everyPage "06t"u<%
* @param currentPage I;xSd.-
* @param totalRecords j-]`;&L
* @return page 7pPaHX8
*/ h;TN$ /
publicstatic Page createPage(int everyPage, int -sjyv/%_
[vv $"$z
currentPage, int totalRecords){ ,X`w/ 2O
everyPage = getEveryPage(everyPage); ya3k;j2C
currentPage = getCurrentPage(currentPage); YMSZcI
int beginIndex = getBeginIndex(everyPage, 'Fq+\J#%
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currentPage); z|Y Ms?
int totalPage = getTotalPage(everyPage, P{m(.EC_
{$>Pg/
totalRecords); c'|](vOd]
boolean hasNextPage = hasNextPage(currentPage, 5aZbNV}-
i,V,0{$
totalPage); =D~>$Y
boolean hasPrePage = hasPrePage(currentPage); JjMa
i}Q"'?
returnnew Page(hasPrePage, hasNextPage, W6c]a/
everyPage, totalPage, njxfBA:
currentPage, 9{*$[%d1
)kMF~S|H
beginIndex); 0RZ[]:(
} Oa.84a
VW`SqUl
privatestaticint getEveryPage(int everyPage){ = Ed0vw
return everyPage == 0 ? 10 : everyPage; X 0vcBHh
} g1kYL$ o4
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sm
privatestaticint getCurrentPage(int currentPage){ ,A%p9
return currentPage == 0 ? 1 : currentPage; OLS/3c
z
} X
aE;i57$l
Z".Xroq~
privatestaticint getBeginIndex(int everyPage, int .Gt_~x
6?(yMSKa
currentPage){ P,J+'.@
return(currentPage - 1) * everyPage; Y_zMj`HE
} xovsh\s
MxgJ+
privatestaticint getTotalPage(int everyPage, int zq(4@S-TU
*^oL$_Y
totalRecords){ 4`e[gvh
int totalPage = 0; q6'Q-e)
!8e;3W
if(totalRecords % everyPage == 0) 5>6:#.f%!e
totalPage = totalRecords / everyPage; :X}n[K
else fc&djd`FuX
totalPage = totalRecords / everyPage + 1 ; F|a'^:Qs
Cs4ks`Z18
return totalPage; ~^TH5n
} R53^3"q~
({3Ap{Q}
privatestaticboolean hasPrePage(int currentPage){ 1/f{1k
return currentPage == 1 ? false : true; lqTc6@:D
} r2*8.j51
\,xa_zeO
privatestaticboolean hasNextPage(int currentPage, H+{@VB
hd*GDjmRQ/
int totalPage){ B:Y F|k}T
return currentPage == totalPage || totalPage == W{%X1::q$
>PzZt8e
0 ? false : true; g=/!Ry=
} "Zfm4Nx"
M5a&eO
@O`T|7v
} uUiS:Tp]
9=q& SG
[l/!&6
jF@BWPtF=
JZdRAL2#v
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。 <Umr2Vw-
K491QXG
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 XV}}A^
5sANF9o!
做法如下: %:s+5*SKe
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 '&+]85_&$
M1]}yTCd
的信息,和一个结果集List: 0xx4rpH
java代码: _NB*+HVo
"F =NDF
! 1Hs;K
/*Created on 2005-6-13*/ ?fN6_x2e3
package com.adt.bo; 's.e"F#
NB4Q,iq$
import java.util.List; UZdGV?o ?
K {kd:pr
import org.flyware.util.page.Page; "=w:LRw
Er;q s *f
/** NLr a"Z
* @author Joa ^Ze(WE)
*/ &~Y%0&F,&
publicclass Result { qm"SN<2S*
;mYZ@g%e
private Page page; ^J&D)&"j
:C>iV+B j
private List content; C1fd@6
twu,yC!
/** XG*> yra`
* The default constructor otdRz<C
*/ z4 <_>)p
public Result(){ Oi'y0S~g
super(); `KtP;nG
} .*f6n|
?em8nZ'
/** _9]vlxgtG(
* The constructor using fields -wrVEH8
* Qd~z<U l
* @param page \vJ0Mhk1
* @param content ol41%q*
*/ '}9 Nvr)+
public Result(Page page, List content){ 7H09\g&
this.page = page; {?Nm"#
this.content = content; }`2a>N:
&
} ^.R!sQ
eKy!Pai
/** w\MWr+4
* @return Returns the content. 4/%fpU2
*/ h=S7Z:IaM
publicList getContent(){ W+GC3W
return content; Vz$xV!
} ,p3]`MG
X4]miUmh
/** eAo+w*D(
* @return Returns the page. m 94PFD@N
*/ &TY74w*
public Page getPage(){ {Ef.wlZ
return page; ii_kgqT^
} }LCm_av
<T?-A}0uO
/** z\oTuW*B
* @param content =}%#j0a4
* The content to set. "9r$*\wOf
*/ nShXY6bA
public void setContent(List content){ pbEWnx_
this.content = content; g<(!>:h
} 0VcHz$
6
l;KrFJ6
/** }A+ncabm
* @param page "T_9_6tH
* The page to set. a7c`[
*/ /='0W3+o*L
publicvoid setPage(Page page){ U+*l!"O,
this.page = page; VsJ+-IHm
} 1Xo0(*O
} (D%vN&F
v@|<.
~h_
_Y>
u.|%@
\wD/TLS}
2. 编写业务逻辑接口,并实现它(UserManager, ,{!,%]bC
:>.{w$Ln%
UserManagerImpl) nKzm.D gt_
java代码: %-yzU/`JF
; ?f+
o S= !6h
/*Created on 2005-7-15*/ 4VZI]3K,
package com.adt.service; ,+
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import net.sf.hibernate.HibernateException; g3c<c S^l
t1YB
import org.flyware.util.page.Page; @]%eL
5"@>>"3U
import com.adt.bo.Result; {Y@shf;
~1D^C |%
/** W,NqevXo:
* @author Joa 2=- .@,6
*/ jhm/<=
publicinterface UserManager { %Y%r2
p~@,zetS
public Result listUser(Page page)throws h\UKm|BZ
lwq:0Rj@Q
HibernateException; s[{[pIH
nf^?X`g
} S?d<P
CdF;0A9.3
=4MTb_
]CF-#q}'
ppRmC,0f^
java代码: g5@JA^\vZT
4WvW11q8U
@>Yd6C
/*Created on 2005-7-15*/ R1X'}#mU
package com.adt.service.impl; .*x:
w[
v{)
import java.util.List; 9^W7i]-Z
S[exnZ*Y
import net.sf.hibernate.HibernateException; A|8"}Hm
~jL%l
import org.flyware.util.page.Page; 0WC\uxT7
import org.flyware.util.page.PageUtil; S~);
(O{OQk;CF
import com.adt.bo.Result; fr/EkL1Dl
import com.adt.dao.UserDAO; ?4%H(k5A
import com.adt.exception.ObjectNotFoundException; Q"dq_8\`U
import com.adt.service.UserManager; H[u9C:}9b
gZ4'
w`4r
/** sNDo@u7
* @author Joa 5P\>$N1p
*/ (M$0'BV0
publicclass UserManagerImpl implements UserManager { Z?{\34lPj
6ieul@?*u*
private UserDAO userDAO; [*^.$s(
,gVVYH?qR
/** DLrV{8%W
* @param userDAO The userDAO to set. E xhih^[_
*/ MvpJ0Y (
publicvoid setUserDAO(UserDAO userDAO){ RG{T\9]n
this.userDAO = userDAO; 9s^$tgH
} QMBT8x/+_'
bFX{|&tHU
/* (non-Javadoc) KkZx6A)$u
* @see com.adt.service.UserManager#listUser M YF
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/eQAGFG
(org.flyware.util.page.Page) p75 o1RU
*/ LZn'+{\`
public Result listUser(Page page)throws aDdGhB
\Ip)Lm0
HibernateException, ObjectNotFoundException { W_2;j)i
int totalRecords = userDAO.getUserCount(); oRCc8&
if(totalRecords == 0) 'nq=xi@RC
throw new ObjectNotFoundException 'IX1WS&\"
{!|4JquE_
("userNotExist"); 3[[oAp
page = PageUtil.createPage(page, totalRecords); DzGUKJh6
List users = userDAO.getUserByPage(page); }_'5Vb_
returnnew Result(page, users); `[sFh%:
} 5`.CzQVb
*)Qv;'U=rn
} Z6zV 9hn
@3?>[R
5)RZJrN]
!d N[9}
mLuNl^)3
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 =sYILe[
U*[E+Uq}:N
询,接下来编写UserDAO的代码: l1 Kv`v\
3. UserDAO 和 UserDAOImpl: 0$)Q@#
java代码: tVRN3fJH
`3F#k[IR
/Sj~lHh
/*Created on 2005-7-15*/ +]%S}<R
package com.adt.dao; T'5{p
|Mq+QDTTw~
import java.util.List; b)I-do+
5*$yY-A
import org.flyware.util.page.Page; O=2|'L'h!
I_<VGU k
import net.sf.hibernate.HibernateException; Bz ;r<Kn
n4kq=Z%
/** ^!1!l-
* @author Joa ^Gk`n
*/ zTg\\z;
publicinterface UserDAO extends BaseDAO { <c}@lj-j
+yP!7]
publicList getUserByName(String name)throws uxf,95<g)
$.jGO!
HibernateException; u(f
jA{5)-g
publicint getUserCount()throws HibernateException; dQj/Sr
OBAO(Ke
publicList getUserByPage(Page page)throws DO:,PZX
bCw{9El!K4
HibernateException; ?#K.D vGJ
*C*ZmC5
} n-ffX*zA(
RM|J |R
tY)L^.* 7
kZw"a*6
C^)Imr
java代码: gs'M^|e)
-%`~3*L
w jkh*Y
/*Created on 2005-7-15*/ <<>+z5D+
package com.adt.dao.impl; aRMlE*yW
~ n]5iGz
import java.util.List; _@ao$)q{J
E'LI0fr
import org.flyware.util.page.Page; 9z#8K
zXg
qi,) l*?f
import net.sf.hibernate.HibernateException; FHOw ]"#
import net.sf.hibernate.Query; y*iZ;Bv j
*cb|9elF^
import com.adt.dao.UserDAO; /whaY4__O\
,{0Y:/T'
/** K3!3[dR*
* @author Joa @Go_5X(
*/ :TQp,CEa
public class UserDAOImpl extends BaseDAOHibernateImpl Ixxs(
Pm/<^z%
implements UserDAO { xWG@<}H
ftYJ 3/ WH
/* (non-Javadoc) O*:87:I d
* @see com.adt.dao.UserDAO#getUserByName Wu][A\3D1
ZE=sw}=
(java.lang.String) +KTfGwKt
*/ 7%^G]AFi
publicList getUserByName(String name)throws /I 7V\
Ugri _
HibernateException { c u/"=]D
String querySentence = "FROM user in class N
)Z>]&5
W;OGdAa_
com.adt.po.User WHERE user.name=:name"; Clum
m@z;#
Query query = getSession().createQuery P =X]'m_B
$Z G&d
(querySentence); xvTtA61Vp
query.setParameter("name", name); o,rF 15
return query.list(); KR?;7*qF
} !P A:#]J
6F(z6_<
/* (non-Javadoc) 0>|q[SC
* @see com.adt.dao.UserDAO#getUserCount() ^EUR#~b5iy
*/ geG0F}oC!
publicint getUserCount()throws HibernateException { wsQnjT>
int count = 0; qf0pi&q
String querySentence = "SELECT count(*) FROM Nh!`"B2B
X?_rD'3
user in class com.adt.po.User"; WzzA:X
Query query = getSession().createQuery ew1L+
..`c# O&
(querySentence); 1ubu~6
count = ((Integer)query.iterate().next hV7EjQp
|
1B0
()).intValue(); #*.!J zOg
return count; oZ%uq78#[%
} &hWELZe0vv
b-&rMML
/* (non-Javadoc) iE'_x$i
* @see com.adt.dao.UserDAO#getUserByPage lju5+0BSb
8&@=Anc&q
(org.flyware.util.page.Page) m^ xTV-#l@
*/ e)e(f"t6Q
publicList getUserByPage(Page page)throws qR@ESJ_
TZgtu+&
HibernateException { E^-c,4'F
String querySentence = "FROM user in class "uBnK!
\tgY2:
com.adt.po.User"; e4YfJd
Query query = getSession().createQuery @D9O<x
zB%~=@Q^6
(querySentence); ? $B4'wc5
query.setFirstResult(page.getBeginIndex()) Gld~GyB\k
.setMaxResults(page.getEveryPage()); @)b'3~D
return query.list(); \Tz|COG5h\
} KGgtEh|
*ra)u-
} ]t0o%w
5Dkb/Iagi
s@L ;3WdO
N]W*ei
Nn_fhc>
至此,一个完整的分页程序完成。前台的只需要调用 WDw<kX 6p
B!&5*f}*
userManager.listUser(page)即可得到一个Page对象和结果集对象 1|sem(t
n{QyqI
的综合体,而传入的参数page对象则可以由前台传入,如果用 08ZvRy(Je<
V[.{cY?6
webwork,甚至可以直接在配置文件中指定。 SWdmej[
8#QT[H
4F
下面给出一个webwork调用示例: UuIjtqW
java代码: .<t {saToU
)>ff"| X
?i<l7
/*Created on 2005-6-17*/ }%XB*pzQ
package com.adt.action.user; \6
\bD<
L\4rvZa
import java.util.List; 8O^x~[sQ
>M5}L<
import org.apache.commons.logging.Log;
f,O10`4s
import org.apache.commons.logging.LogFactory; J^"_H:1[
import org.flyware.util.page.Page; :cA P{rSe
1:eWZ]B5"
import com.adt.bo.Result; =o(}=T>:"
import com.adt.service.UserService; R,T 0!f
import com.opensymphony.xwork.Action; 'ON/WKJr|W
va@;V+cD
/** ;W{z"L;nX
* @author Joa 5j`sJvq
*/ -)-:rRx-
publicclass ListUser implementsAction{ T.#_v#oM
rRevyTs
privatestaticfinal Log logger = LogFactory.getLog 8J,^O04<
^$oa`B^2JM
(ListUser.class); Apu-9|oP
]:f.="
private UserService userService; ^?e[$}
>.SO2w
private Page page; <);j5)/
Uv59 XF$
privateList users; M.H!dZ
S:!5|o|
/* KLe6V+ki*
* (non-Javadoc) ~T}D#}
* E zcch1
* @see com.opensymphony.xwork.Action#execute() "*zDb|v
*/ }zA|M9%E
publicString execute()throwsException{ g(P7CX+y
Result result = userService.listUser(page); /,I?"&FWc
page = result.getPage(); u4lM>(3Y}
users = result.getContent(); ^fKKsfIf
return SUCCESS; .yF-<Y
} n*GB`I*g
MO~T_6
/** 5^uX!_r`
* @return Returns the page. _U}|Le@ e
*/ 5{-Hg[+9
public Page getPage(){ M0m%S:2
return page; A]"6/Lr9P
} ,GWa3.&.d
yMW3mx301j
/** N_D=j6B
* @return Returns the users. g,E)F90
*/ v0r:qku
publicList getUsers(){ 70avr)OM
return users; Cdl"TZ<
} jGLmgJG-P
~H''RzN
/** y2%[/L:u~
* @param page em'3 8L|(
* The page to set. Q-,
4
*/ k&yBB%g
publicvoid setPage(Page page){ a\-5tYo`u
this.page = page; tQj=m_
} !o'a]8
h9Sf
/** +4t
\j<T
* @param users U-?r>K2
* The users to set. LZ#A`&qUd
*/ K{y`Sb~k
publicvoid setUsers(List users){ x^3K=l;N
this.users = users; qUe2(/TQu
} <mLU-'c@
v-$X1s
/** !6.LSY,E
* @param userService bjUe+#BL
* The userService to set. "7alpjwb
*/ 2aivc,m{r
publicvoid setUserService(UserService userService){ &}gH!5L m
this.userService = userService; ]mBlXE:Z
} #)D$\0ag
} BI2'NN\
[e=k<gKH
&hpznIN
D6_#r=08
Jv2V@6a(
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, %Y`)ZKh
eJOo~HIWQ
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 0NsPo
)$Fw<;4
么只需要: @6 jKjI
java代码: ;).QhHeg>
`5t~
Vlp
99h#M3@!
<?xml version="1.0"?> /\jRr7 Cd
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork -?T|1FA,
^-#:T
1.0//EN" "http://www.opensymphony.com/xwork/xwork- vO{[P#L}
1iY?t
1.0.dtd"> k:s86q
-% B)+yq>
<xwork> k<