Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 y-{?0mLq
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 \2CEEs'
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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 ;vy<!@Y;8
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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 k 7:Z\RGy
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分页支持类: sKk+^.K}|
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java代码: 4W}mPeEeV
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package com.javaeye.common.util; ,T$ GOjt
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import java.util.List; zrf
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publicclass PaginationSupport { t7Mq>rFB
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publicfinalstaticint PAGESIZE = 30; *F!1xyg
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privateint pageSize = PAGESIZE; p$uPj*
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privateList items; a&UzIFdB
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privateint totalCount; mxpj<^n}
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privateint[] indexes = newint[0]; [A~ Hl
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privateint startIndex = 0; @BG].UJo
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public PaginationSupport(List items, int y#th&YC_b
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totalCount){ r-yUWIr
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setPageSize(PAGESIZE); 43]y]/do
setTotalCount(totalCount); ;<_a ,5\Q
setItems(items); HUAYtUBH
setStartIndex(0); Js vdC]+
} F-oe49p5e
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public PaginationSupport(List items, int A^#\=ZBg1
ch25A<O<R.
totalCount, int startIndex){ |:.Uw\z5'
setPageSize(PAGESIZE); JgA{1@h
setTotalCount(totalCount); a(=lQ(v/?
setItems(items); 3u& ,3:
setStartIndex(startIndex); 6`20
} 9[;da
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public PaginationSupport(List items, int |cgjn*a?M
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totalCount, int pageSize, int startIndex){ M=lU`Sm
setPageSize(pageSize); +:4>4=
setTotalCount(totalCount); >TY;l3ew
setItems(items); 1dw{:X=j
setStartIndex(startIndex); \"))P1
} d9BFeq8
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publicList getItems(){ s\pukpf@
return items; p6K ~b
} &)gc{(4$
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publicvoid setItems(List items){ *OznZIn
this.items = items; BAY e:0
} 0 !{X8>x
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publicint getPageSize(){ xPPA8~Dm*
return pageSize; Y0T :%
} u[Kz^ga<
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publicvoid setPageSize(int pageSize){ [rWBVfm
this.pageSize = pageSize; K) fKL
} @j_o CDS
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publicint getTotalCount(){ P.C?/7$7Z+
return totalCount; |Z{#DOT
} I;%1xdPt
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publicvoid setTotalCount(int totalCount){ _uLpU4# ?
if(totalCount > 0){ #qYgQ<TM!
this.totalCount = totalCount; pu]U_Ll@
int count = totalCount / wbrOL(q.m
hxH6Ii]\
pageSize; $qz{L~ <
if(totalCount % pageSize > 0) dk
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count++; A,~KrRd
indexes = newint[count]; 5WJ ~%"O
for(int i = 0; i < count; i++){ ndzADVP
indexes = pageSize * a1y<Y`SC9
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i; {?0'(D7.
} %UrNPk
}else{ I`X!M!dB)
this.totalCount = 0; SsTBjIX
} 6qFzo1LO
} IDT\hTPIs
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publicint[] getIndexes(){ 5L[imO M0
return indexes; D]fuX|f~ul
} m+;U,[%[*E
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publicvoid setIndexes(int[] indexes){ <O0tg[ub
this.indexes = indexes; i0K 2#}=^
} (ct1i>g
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publicint getStartIndex(){ 1F,U^O
return startIndex; oo\^}jb
} %%}l[W
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publicvoid setStartIndex(int startIndex){ //BJaWq
if(totalCount <= 0) [|oG}'Xz
this.startIndex = 0; 1C{0 R.
elseif(startIndex >= totalCount) Si]?4:E7=
this.startIndex = indexes (WC
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[indexes.length - 1]; A;Y~Hu4KPZ
elseif(startIndex < 0) 0*b8?e
this.startIndex = 0; :38h)9>RK
else{ 5?SE?VC=t
this.startIndex = indexes 2|lR@L sr
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[startIndex / pageSize]; v4s4D1}
} bWp:!w#K
} W,6q1
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publicint getNextIndex(){ JI]Lz1i
int nextIndex = getStartIndex() + f&4+-w.:V|
y EfAa6
pageSize; s(3u\#P
if(nextIndex >= totalCount) m_oUl(pk
return getStartIndex(); _Sfu8k>):
else /C Xg$%\
return nextIndex; -LRx}Mb9
} ,.p
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publicint getPreviousIndex(){ Nuot[1kS
int previousIndex = getStartIndex() - ;&=CZ6vH
}.)R#hG?
pageSize; >8I~i:hn
if(previousIndex < 0) 3]?='Qq.(
return0; Ebs]]a>PO
else "zJ xWXI
return previousIndex; k1xx>=md|C
} 1a(\F7
j%
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} lqOpADLS3
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抽象业务类 ?wG
java代码: i
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/** DSRc4|L
* Created on 2005-7-12 i4D]>
*/ #oTVfY#
package com.javaeye.common.business; g]L8Jli
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import java.io.Serializable; F]6G<6T[
import java.util.List; I2CI9,0
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import org.hibernate.Criteria; 'XKfKv >;
import org.hibernate.HibernateException; A"M;kzAfHM
import org.hibernate.Session; _0rt.NRD
import org.hibernate.criterion.DetachedCriteria; qzxWv5UH
import org.hibernate.criterion.Projections; 5A`>3w{3n
import 0Sd>*nC
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org.springframework.orm.hibernate3.HibernateCallback; 1$E [`` n
import /]z#V'
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org.springframework.orm.hibernate3.support.HibernateDaoS 153*b^iDBh
18%$Z$K,
upport; A,EG0yb
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import com.javaeye.common.util.PaginationSupport; @4*eH\3
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public abstract class AbstractManager extends i=n;rT
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HibernateDaoSupport { L@[}sMdq(
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privateboolean cacheQueries = false; 3l~7
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privateString queryCacheRegion; =p[Sd*d
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publicvoid setCacheQueries(boolean Xk%eU>d
vo
}4N[]Sb
cacheQueries){ o'$-
this.cacheQueries = cacheQueries; .jP|b~
} P??P"^hU
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publicvoid setQueryCacheRegion(String }|Q\@3&
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queryCacheRegion){ B^TgEr
this.queryCacheRegion = I/St=-;
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queryCacheRegion; K{I "2c
} IxWi>8
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publicvoid save(finalObject entity){ <ndY6n3
getHibernateTemplate().save(entity); J)Yz@0#T(;
} Hfj.8$
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publicvoid persist(finalObject entity){ -2}ons(
getHibernateTemplate().save(entity); y{(Dv}
} j07A>G-=
Cd^1E]O0{
publicvoid update(finalObject entity){ !U4YA1>>
getHibernateTemplate().update(entity); g/$RuT2U
} GL0P&$h
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publicvoid delete(finalObject entity){ R$u1\r1I
getHibernateTemplate().delete(entity); F7C+uGTs
} 4Hf'/%kW
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publicObject load(finalClass entity, ~5|R`%
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finalSerializable id){ s~(`~Y4
return getHibernateTemplate().load )Az0.}
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(entity, id); Es}`SIe/
} ^2BiMH3j
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publicObject get(finalClass entity, S3HyB
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finalSerializable id){ g51UIN]o-
return getHibernateTemplate().get a|y'-r90
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(entity, id); jpYZ)
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} KIY`3Fl09
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publicList findAll(finalClass entity){ HI:1Voy
return getHibernateTemplate().find("from t; #@t/`
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" + entity.getName()); N@X6Z!EO
} *=O3kUoL
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publicList findByNamedQuery(finalString ib> ~3s;
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namedQuery){ 9k9}57m.i
return getHibernateTemplate 'HV@i)h0%V
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().findByNamedQuery(namedQuery); I4qS8~+#
} H^o_B1
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publicList findByNamedQuery(finalString query, 0RSzDgX
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finalObject parameter){ }3WP:Et
return getHibernateTemplate Jc]k\U
SCn)j:gH;
().findByNamedQuery(query, parameter); NuF?:L[
} $mAyM+ ph[
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publicList findByNamedQuery(finalString query, p/LV^TQ
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finalObject[] parameters){ @+Nf@LJ
return getHibernateTemplate fY=:geB
hc]p^/H
().findByNamedQuery(query, parameters); T_wh)B4xW
} )iC@n8f7o
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publicList find(finalString query){ 7&jq =
return getHibernateTemplate().find 3 TV4|&W;
* _usVg
(query); 8qfXc
^6
} @Wm:Rz
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publicList find(finalString query, finalObject =%I;Y& K
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parameter){ S&l [z,
return getHibernateTemplate().find %<O~eXY
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(query, parameter); 1x##b[LC
} /Wl8Jf7'
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public PaginationSupport findPageByCriteria plr3&T~,&S
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(final DetachedCriteria detachedCriteria){ L|b[6[XTHL
return findPageByCriteria 2*gB ~Jn4
p,(W?.ZDN?
(detachedCriteria, PaginationSupport.PAGESIZE, 0); c*R\fQd
} Ed-3-vJej6
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public PaginationSupport findPageByCriteria I;?PDhDb
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(final DetachedCriteria detachedCriteria, finalint s6}SdmE
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startIndex){ I
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return findPageByCriteria &oZU=CN
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(detachedCriteria, PaginationSupport.PAGESIZE, @x[A^
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startIndex); \j.l1O
} T.%yeJiE
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public PaginationSupport findPageByCriteria sUiO~<Ozpk
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(final DetachedCriteria detachedCriteria, finalint _T805<aUW\
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pageSize, k7sD"xR3
finalint startIndex){ dxS5-aWy9w
return(PaginationSupport) Cd6th
F)
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getHibernateTemplate().execute(new HibernateCallback(){ z'O+B}
publicObject doInHibernate k1P'Q&Na
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(Session session)throws HibernateException { kPA g*
Criteria criteria = rY@9nQ\>g
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detachedCriteria.getExecutableCriteria(session); Q_0_6,Opb
int totalCount = 23'<R i
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((Integer) criteria.setProjection(Projections.rowCount 4Xwb`?}-
/Q89 y[
()).uniqueResult()).intValue(); !`W0;0'Zg
criteria.setProjection c|k(_#\B
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(null); oxI?7dy5
List items = 7GErh,
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criteria.setFirstResult(startIndex).setMaxResults rmWsob
CQ{{J{pU"
(pageSize).list(); JIYzk]Tj
PaginationSupport ps = 68<W6z
_sL;E<)y(
new PaginationSupport(items, totalCount, pageSize, U(OkTJxv+
tt6GtYrC 1
startIndex); +nB0O/m'U
return ps; RHbbj}B
} ;v.J
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}, true); r%$\Na''
} #3RElI
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public List findAllByCriteria(final v:w^$]4
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DetachedCriteria detachedCriteria){ hOFvM&$
return(List) getHibernateTemplate >r}?v3QW
}!|$;3t+c
().execute(new HibernateCallback(){ >@-.rkd(
publicObject doInHibernate q]Xu #:X
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(Session session)throws HibernateException { XW^Pz(
Criteria criteria = xh25 *y
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detachedCriteria.getExecutableCriteria(session); \O,yWyU4
return criteria.list(); q['3M<q
} }5$le]
}, true); Yn?Xo_Y
} TT#V'r\
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public int getCountByCriteria(final lh XD9ed
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DetachedCriteria detachedCriteria){ Dk2Zl
Integer count = (Integer) ~,8#\]xR
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getHibernateTemplate().execute(new HibernateCallback(){ L`9.Gf
publicObject doInHibernate E7w^A
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(Session session)throws HibernateException { F8/n;
Criteria criteria = ;WrG\R/|
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detachedCriteria.getExecutableCriteria(session); VyNU<}
return Pj BBXI1i
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criteria.setProjection(Projections.rowCount Y 9st3
9U )9u["DH
()).uniqueResult(); T@zp'6\H
} )!G 10
}, true); nT}i&t!q8@
return count.intValue(); Q{miI
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} \.P#QVuQ
} :w4N*lV-
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用户在web层构造查询条件detachedCriteria,和可选的 Q+_z*
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 t.bM]QU!1
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PaginationSupport的实例ps。 *7L1SjZw
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ps.getItems()得到已分页好的结果集 J?4dafkw
ps.getIndexes()得到分页索引的数组
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ps.getTotalCount()得到总结果数 28-z
ps.getStartIndex()当前分页索引 I,]q;lEMt
ps.getNextIndex()下一页索引 :RBeq,QaO
ps.getPreviousIndex()上一页索引 >Af0S;S
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 i;IhsKO0R
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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 66_=bd(9
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一下代码重构了。 Rz*GRe
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我把原本我的做法也提供出来供大家讨论吧: vuJEPn%
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首先,为了实现分页查询,我封装了一个Page类: A#i[Us|
java代码: #2Iw%H 2q&
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/*Created on 2005-4-14*/ @s,kx.S
package org.flyware.util.page; ''z]o#=^9
;!3: 3;
/** Q0ba;KPm
* @author Joa X_,R!$wbg:
* (FGHt/!
*/ Qz$nWsD
publicclass Page { |BD2=7,z
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/** imply if the page has previous page */ WU,b<PU &
privateboolean hasPrePage; axN\ZXU
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/** imply if the page has next page */ hVd_1|/X
privateboolean hasNextPage; 8;f5;7Mn
#v6<9>%
/** the number of every page */ \uJ+~db=
privateint everyPage; I"Ko sSs
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/** the total page number */ Qj|tD+<
privateint totalPage; wuSotbc/
6/"#pe^
/** the number of current page */ `/B+
privateint currentPage; z+zEH9.'
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/** the begin index of the records by the current :1]J{,VG
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query */ |PGTP#O<
privateint beginIndex; 95ix~cH3q
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/** The default constructor */ 'tX}6wurf
public Page(){ mSk";UCn
8-@HzS%
} QDKY7"H
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/** construct the page by everyPage g\iSc~%?
* @param everyPage wk1/&
* */ WB `h)
public Page(int everyPage){ zp``e;gY
this.everyPage = everyPage; vM:c70=
} BD]o+96qP
Ip *8R]W
/** The whole constructor */ Pw6%,?lQ
public Page(boolean hasPrePage, boolean hasNextPage, 38:5g_
{7_C|z:'p&
e ]{=#
int everyPage, int totalPage, (iJ
/
int currentPage, int beginIndex){ ^7=h%{>=
this.hasPrePage = hasPrePage; >Dz8+y
this.hasNextPage = hasNextPage; =hI;5KF
this.everyPage = everyPage; TS=U%)Ik
this.totalPage = totalPage; ;sx4w!Y,
this.currentPage = currentPage; s'Qmrs
a
this.beginIndex = beginIndex; :H:+XIgoR
} -e0?1.A$
R+.kwq3CED
/** vw-y:,5`t8
* @return h&~9?B
* Returns the beginIndex. 2~V"[26t
*/ 6(ER$
publicint getBeginIndex(){ k(@W
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return beginIndex; ]a[2QQ+g
} :0bjPQj
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/** 9eR";Wm])
* @param beginIndex 'rVB2
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* The beginIndex to set. Id8e%)
*/ E;q+u[$
publicvoid setBeginIndex(int beginIndex){ >T{TE"XyO|
this.beginIndex = beginIndex; JE<h
} Fw#1?/K~
DV)NY!
/** I<Mb/!TQ
* @return oE0~F|(\1
* Returns the currentPage. i8f +woZL
*/ bh3yH>Zns
publicint getCurrentPage(){ 4RH>i+)pS\
return currentPage; 5s>>]
.%
} B^{~,'
HC6v#-( `{
/** T#vY(d
* @param currentPage Rv.IHSQUo
* The currentPage to set. vV"I}L
*/ QcjsQTAbk
publicvoid setCurrentPage(int currentPage){ NH*"AE;
this.currentPage = currentPage; 7Rc>LI*
'
} 6:Y2z!MLO
D'^UZZlI^I
/** @twi<U_
* @return r>sXvzv
* Returns the everyPage. JEP9!y9y
*/ RPjw12Ly
publicint getEveryPage(){ EZT 8^m
return everyPage; Q9;VSF)
} *Y!RU{w+Z
b~<:k\EE
/** f>&*%[fw
* @param everyPage *<}R=X.
* The everyPage to set. %:sP #BQM
*/ "_=t1UE
publicvoid setEveryPage(int everyPage){ bXqTc2>=
this.everyPage = everyPage; 7`^=Ie%(K
} KUUZN
,8cVv->u/
/** p1T0FBV
L
* @return 5'<a,,RKu
* Returns the hasNextPage. NSq29#
*/ 'a:';hU3f
publicboolean getHasNextPage(){ R0bgt2J
return hasNextPage; FL&L$#X
} <UTO\w%
Zcg-i:@
/** ,C:^K`k&
* @param hasNextPage *r7%'K{C
* The hasNextPage to set. R38
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*/ 8m#y>`
publicvoid setHasNextPage(boolean hasNextPage){ $I<\Yuy-M9
this.hasNextPage = hasNextPage; |;I"Oc.w^R
} 7f<@+&
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/** ~B7<Yg
* @return VZ7E#z+nM#
* Returns the hasPrePage. *?>52 -&b
*/ ih|&q
publicboolean getHasPrePage(){ ,vBB". LY'
return hasPrePage; zz8NBO
} z(#dL>d$'
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/** IYr}%:P)
* @param hasPrePage nB/`~_9
* The hasPrePage to set. ?u0qYep:
*/ i@ 86Ez
publicvoid setHasPrePage(boolean hasPrePage){ iP1yy5T
this.hasPrePage = hasPrePage; H29vuGQjq
} k7(lwEgNG
k ,ezB+
/** iRM ?_|
* @return Returns the totalPage. &vfeBth
* ?=HoU3
*/ J0o,ZH9
publicint getTotalPage(){ <~u-zaN<W
return totalPage; 3{TE6&HIa
} zy|h1.gd
Z2-"NB
/** aY DM)b}
* @param totalPage =4OV
}z=I
* The totalPage to set. }C$D-fH8sW
*/ `3z6y&dmx
publicvoid setTotalPage(int totalPage){ 1KjzKFnb
this.totalPage = totalPage; tg9{(_t/W
} Zq:c2/\c}
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+
} !LsIHDs4
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tq L2' (=
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 }*vE/W
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个PageUtil,负责对Page对象进行构造: t"5ZYa
java代码: R?Ch8mW.!
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ay
/*Created on 2005-4-14*/ ]H<}6}Gd
package org.flyware.util.page; V|/N-3M
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import org.apache.commons.logging.Log; 6w_TL<S
import org.apache.commons.logging.LogFactory; |;"(C# B
?uW}
XAi
/** Cn_r?1{W
* @author Joa M}
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* 2;w> w#}>
*/ Ci2*5n<
publicclass PageUtil { lbh7`xCR
/XdLdA!v
privatestaticfinal Log logger = LogFactory.getLog &3itBQF
=p dLh
(PageUtil.class); 474
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}n
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/** (@bq@0g
* Use the origin page to create a new page QoMa+QTuc
* @param page 9Fg:
* @param totalRecords .Y }k@T40a
* @return +6L.a3&(b
*/ cs4IO
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publicstatic Page createPage(Page page, int }|j#C[
vorb? iVf>
totalRecords){ bzZ7L-yD
return createPage(page.getEveryPage(), DW)X3A(^
VmZDU(M
page.getCurrentPage(), totalRecords); OD?y
} ?Iag-g9#=m
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/** gRZ!=z[&
* the basic page utils not including exception *r|13|k
#fXy4iL l
handler >xXq:4l>}
* @param everyPage 9j5B(_J^
* @param currentPage XMaw:Fgr
* @param totalRecords z$VVt?K
* @return page GY"c1KE$
*/ kc2
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publicstatic Page createPage(int everyPage, int jV<5GWq
+^.xLTX`$
currentPage, int totalRecords){ Wxi;Tq9C@_
everyPage = getEveryPage(everyPage); Q v},X~^R
currentPage = getCurrentPage(currentPage); g9IIC5
int beginIndex = getBeginIndex(everyPage, jPg[LZQ'
0QEcJ]Qb8
currentPage); TjpAJW@-
int totalPage = getTotalPage(everyPage, |:`)sx3@#
lGJ&\Lv:
totalRecords); v2YU2-X[
boolean hasNextPage = hasNextPage(currentPage, BLm}mb#/{
1\/~>
totalPage); AU;Iif6
boolean hasPrePage = hasPrePage(currentPage); V h5\'Sn
%Kh}6
returnnew Page(hasPrePage, hasNextPage, CM t$)
everyPage, totalPage, z*o2jz?t4
currentPage, bvT$/(7
`u8(qGg7GF
beginIndex); r'@7aT&_
} bKh}Y`
d~T@fa
privatestaticint getEveryPage(int everyPage){ <<9|*Tz
return everyPage == 0 ? 10 : everyPage; )[=C@U
} {l\Ep=O vx
-:Q"aeC5
privatestaticint getCurrentPage(int currentPage){ Wq<HsJd/
return currentPage == 0 ? 1 : currentPage; y"H(F,(N
} %-|$7?~
khQfLA
privatestaticint getBeginIndex(int everyPage, int `'pfBVBz
eGWwPSIp
currentPage){ 'a~F'FN$
return(currentPage - 1) * everyPage; =~q$k
}
`Y,Rk
I~-sBMm(w
privatestaticint getTotalPage(int everyPage, int 6~6 vwp
xSq+>, b
totalRecords){ )H&ZHaO,_
int totalPage = 0; kAW2vh
r]S"i$
if(totalRecords % everyPage == 0) .EjjCE/v-
totalPage = totalRecords / everyPage; DH.CAV
else zXe]P(p<
totalPage = totalRecords / everyPage + 1 ; 0bu!(Tpg7
qR4-~p8
return totalPage; vI(CX]o
} p1IN%*IV+o
+}BKDEb
privatestaticboolean hasPrePage(int currentPage){ UAC"jy1D
return currentPage == 1 ? false : true; /KlSI<T@
} UUvR>5@n
k7 Ne(4P
privatestaticboolean hasNextPage(int currentPage, 6hHMxS^o
^vI`#}?
int totalPage){ w=~X 6[+3
return currentPage == totalPage || totalPage == /5Yl, P
2TQ<XHA\
0 ? false : true; S4!B;,?AxN
} }3-`e3
t;y@;?~
hKems3
} "~"=e
<V|\yH9
9zpOp-K6
f2ck=3
m-Se-aF
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。 bc2S?u{
6dRvx;d
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 OZe`>Q6
- P4X@s_;
做法如下: 5 &]a8p{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?VyiR40-Cx
T5_rPz
的信息,和一个结果集List:
$;)A:*e
java代码: rt\.|Hr4s
0aYoc-( A
6L-3cxqf\
/*Created on 2005-6-13*/ U \F ?{/
package com.adt.bo; o9Tsyjbj
:T#f&|Gg;
import java.util.List; Mp@dts/|
=3GgfU5k
import org.flyware.util.page.Page; L;
<Pod
IkQ,#Bsb[
/** bFJ>+ {#
* @author Joa 9Wdx"g52_D
*/ r$,Xv+}
publicclass Result { -hGLGF??
$8Gj9mw4e'
private Page page; mD,fxm{G
q oz[x
private List content; VrJf g
5zF$Q {3
/** 5$*=;ls>J
* The default constructor
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*/ zSBR_N51
public Result(){ F 2Mxcs*M
super(); H)X&5E
} y`pgJO
t1!>EI`
/** kU{a!ca4
* The constructor using fields ,/dW*B
* es\Fn#?O
* @param page @$;I%
* @param content 0fN;
L;v
*/ h<g2aL21?F
public Result(Page page, List content){ VD+v\X_
this.page = page; |[$TT$Fb
this.content = content; OS=~<ba
} +]e) :J
caL\ d
/** $]J<^{v
* @return Returns the content. s=<65
*/ a@C}0IP)
publicList getContent(){ 0*KL*Gn
return content; QH k jxj
} Yd<9Y\W%?
~8)l/I=`);
/** I-W,C&J>
* @return Returns the page. pR!m
*/ |Pv)&'B"
public Page getPage(){ k:z)Sw
return page; $@~sO0q
}
L$@qEsO
c7]0>nU;
/** 9x#Tj/5%
* @param content ?:+p#&I
* The content to set. Am >b 7Z!
*/ {gB9EGY
public void setContent(List content){ ]#W9l\
this.content = content; 6U1_Wk?
} 2F/oWt|w?
NH+N+4dEO
/** $?DEO[p.
* @param page ,2mq}u>WU
* The page to set. q<cxmo0S
*/ >oapw5~5
publicvoid setPage(Page page){ <Kk?BRxi
this.page = page; Xc<Hm
} hwSxdT6
} ?2K~']\S
l=<},_]{
S) `@)sr
qCm8R@
VwT&A9&{8
2. 编写业务逻辑接口,并实现它(UserManager, .RWq!Z=)3
_D8:p>=
UserManagerImpl) _TbvQY
java代码: RG_6&
A
}5}#QHF
}-p-(
/*Created on 2005-7-15*/ #r@>.S=U]
package com.adt.service; .i1|U8" X
88l{M[B2
import net.sf.hibernate.HibernateException; p\tA&>3-
.+5;AtN
import org.flyware.util.page.Page; hSaw)g`w
CJ6v S
import com.adt.bo.Result; %U9f`qE
+a^0Q
F-7
/** 1+xi1w}3a
* @author Joa QiNLE'19^
*/ 27Vx<W
publicinterface UserManager { CW,|l0i
e_3B\59k
public Result listUser(Page page)throws ,8stEp9~h]
YOUX
HibernateException; ~oRT@E
H5be 5
} L8KaK
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l=47#zbpZ]
xj JoWB
5oo6d4[
java代码: (Vt5@25JW
Us3zvpy)o
e/$M6l$Q*4
/*Created on 2005-7-15*/ J!yK/*sO,
package com.adt.service.impl; )ZpMB
s 4n<k]d
import java.util.List; i1!Y{
&0OH:P%
import net.sf.hibernate.HibernateException; B.#-@
>bg{
import org.flyware.util.page.Page; hfs QAa
import org.flyware.util.page.PageUtil; bUc++M
hPt=j{aJ%<
import com.adt.bo.Result; ^CB@4$!
import com.adt.dao.UserDAO; PrF('PH7i
import com.adt.exception.ObjectNotFoundException; 3lgD,_&
import com.adt.service.UserManager; x6Q_+!mnk
\psO$TxF=
/** fF.+{-.
* @author Joa +B4 i,]lCx
*/ R[H#av
publicclass UserManagerImpl implements UserManager { \M~uNWv|
B X O,
private UserDAO userDAO; |lh&l<=(f
UL xgvq
/** l;h5Y<A%?
* @param userDAO The userDAO to set. *7),v+ET
*/ GZ.KL!,R!
publicvoid setUserDAO(UserDAO userDAO){ cpx:4R,
this.userDAO = userDAO; U \jFB*U
} 0VIR=Pbp
vSk1/
/* (non-Javadoc) S0;s
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* @see com.adt.service.UserManager#listUser cK'}+
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(org.flyware.util.page.Page) vH6.;j'^
*/ TU9$5l/;g
public Result listUser(Page page)throws N'?#g`*KW
K\5/ ||gi
HibernateException, ObjectNotFoundException { ge%tj O
int totalRecords = userDAO.getUserCount(); m21H68y
if(totalRecords == 0) 4cDe'9
LA
throw new ObjectNotFoundException b>nwX9Y/U
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("userNotExist"); _"82W^W i
page = PageUtil.createPage(page, totalRecords); Nk?/vMaw
List users = userDAO.getUserByPage(page); ]F"@+_E
returnnew Result(page, users); {Vf].l:kn
} xxpzz(S ]A
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} mA5sK?W
\Lm`jU(:l
"f-HOd\=
M?I^`6IOc8
{ApjOIxk
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 H2CpZK'
gVs@T'
询,接下来编写UserDAO的代码: 8B6-f:
3. UserDAO 和 UserDAOImpl: Q 2B
java代码: ex|h&Vma2V
#m3!U(Og`
_hEr,IX=J
/*Created on 2005-7-15*/ ]x6rP
package com.adt.dao; =@MJEo` D
iT</
import java.util.List; RIFTF
R
LPkl16yZ
import org.flyware.util.page.Page; |^gnT`+
Bm&6
import net.sf.hibernate.HibernateException; ;t4YI7E*
`?SLp
/** ]vH:@%3U
* @author Joa &,$N|$yK}|
*/ ra^"Vr
publicinterface UserDAO extends BaseDAO { <BK?@Xy
Z5[g[Q
publicList getUserByName(String name)throws Ce} m_
Uf~5Fc1d =
HibernateException; LB^xdMXi
MZ>Q Rf
publicint getUserCount()throws HibernateException; jH37{S-
eCG{KCM~_Z
publicList getUserByPage(Page page)throws mnU8i=v0A
p+${_w>pl{
HibernateException; euET)Ccq
b
T** y?2
} cpphnGj5
C9eisUM
]aYuBoj
2h1P!4W85
YAd%d|Q
java代码: "lL/OmG
rW`l1yi*$
Xi!e=5&Pa
/*Created on 2005-7-15*/ 1tl qw
package com.adt.dao.impl; vZXdc+2l
c9+yU~(
import java.util.List; UtHloq(r
J@qLBe(v
import org.flyware.util.page.Page; n_*.i1\'w
rGay~\
import net.sf.hibernate.HibernateException; =sk#`,,:
import net.sf.hibernate.Query; =0SJf 3
j2mMm/kq\
import com.adt.dao.UserDAO; Qki?
>j"
TwKi_nh2m
/** =tl~@~pqI
* @author Joa Pxgul7
*/ *TPWLR ^
public class UserDAOImpl extends BaseDAOHibernateImpl Y /l~R7
wqgKs=y
implements UserDAO { hbs /S
hd)WdGJp
/* (non-Javadoc) DkW^gt
* @see com.adt.dao.UserDAO#getUserByName \+k~p:d_8
vILgM\or
(java.lang.String)
=)J<R;
*/ `tl -] ^Y2
publicList getUserByName(String name)throws fP
llN8n
qf{HGn_9~1
HibernateException { wcGv#J],
String querySentence = "FROM user in class n/YnISt
ulfs Z:
com.adt.po.User WHERE user.name=:name"; lLI%J>b@
Query query = getSession().createQuery 6sT(t8[
gwFW+*h
(querySentence); 6xu%M&ht
query.setParameter("name", name); OXbC\^qo@
return query.list(); !wKiMgLS
} h7AO5"6
k;r[m,$
/* (non-Javadoc) EBpg
* @see com.adt.dao.UserDAO#getUserCount() HstL'{&,-m
*/ h;~NA}>
publicint getUserCount()throws HibernateException { +P.JiH`\=
int count = 0; l`a_0
String querySentence = "SELECT count(*) FROM "e/"$z'ca
7?\r9bD
user in class com.adt.po.User"; B)rBM
Query query = getSession().createQuery ovaX_d)cU
zo@,>'m
(querySentence); .I%B$eH
count = ((Integer)query.iterate().next f4vdJ5pV
Hro)m"
()).intValue(); W >|'4y)
return count;
!$<Kp6
} >L$9fn/J
*p|->p6,u
/* (non-Javadoc) SKGnx
* @see com.adt.dao.UserDAO#getUserByPage !e('T@^u6u
?\zyeWK0L
(org.flyware.util.page.Page) boZ/*+t
*/ ;HiaX<O!
publicList getUserByPage(Page page)throws -?Cu-'
LYTnMrM
HibernateException { }TDq7-(g
String querySentence = "FROM user in class ^BP4l_rO9
1+Vei<H$
com.adt.po.User"; MPLeqk$;
Query query = getSession().createQuery tZ:fOM
ACF_;4%&
(querySentence); .:tR*Kst`7
query.setFirstResult(page.getBeginIndex()) D2zqDo<+;
.setMaxResults(page.getEveryPage()); SRrp=>w?
return query.list(); ML%JTx0+Z
} u3sr"w&
|V^f}5gd
} K]&GSro
l>)+HoD
%m$t'?
2
S2;LB
,/[1hhP@
至此,一个完整的分页程序完成。前台的只需要调用 Ld=6'C8ud
x[$:^5V
userManager.listUser(page)即可得到一个Page对象和结果集对象 ]Nue1xV_
i'}"5O+
的综合体,而传入的参数page对象则可以由前台传入,如果用 N5b&tJbM0
N8X)/W
webwork,甚至可以直接在配置文件中指定。 n% s$!R-\
2(R{3E4.
下面给出一个webwork调用示例: g^^^fKUp )
java代码: b)T6%2
~}Z{hs)
B&}lYo
/*Created on 2005-6-17*/ <lWBhrz
package com.adt.action.user; ~u r}6T
x_= 3!)
import java.util.List; A64c,Uv
|xpOU*k
import org.apache.commons.logging.Log; " pL5j
import org.apache.commons.logging.LogFactory; u3HaWf3
import org.flyware.util.page.Page; Apkb!"}>
~-~iCIaTb
import com.adt.bo.Result; (AHTv8
import com.adt.service.UserService; #c-Jo[%G
import com.opensymphony.xwork.Action; q\Z9.T+Qo
%@%~<U)W
/** g5
y*-t
* @author Joa >,f5 5
*/ 4n%|h-!8
publicclass ListUser implementsAction{ _;-b ZH
H+Q_%%[N
privatestaticfinal Log logger = LogFactory.getLog ]K<7A!+@@p
ZOL#Q+U
(ListUser.class); `U{#;
epP_~TU
private UserService userService; a(x#6
:oJ!9\5
private Page page; 5gwEr170
Bc}e ??F
privateList users; ^!SwY_>
n'@XgUI,
/* V}Pv}j:;
* (non-Javadoc) u)l[*";S
* l{.
XhB
* @see com.opensymphony.xwork.Action#execute() g]._J
*/ d^`n/"Ice
publicString execute()throwsException{ I5g!c|#y
Result result = userService.listUser(page); ?<soX8_1
page = result.getPage(); , D`\
RV
users = result.getContent(); wVUm!Y
return SUCCESS; g+=f=5I3
} Y+3r{OI
m_UzmWF
/** Y>K3.*.
* @return Returns the page. l I+KT_|L
*/ %UCuI9
public Page getPage(){ =`wnng5m
return page; 6Ou[t6
} Il!#]
TzsNhrU{
/** 0,m@BsK
* @return Returns the users. PL*kjrLu7
*/ vrXNa8,L
publicList getUsers(){ d~O)mJ
J
return users; m[&