Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Mu,}?%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 I}djDtJ
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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 +gZg7]!Z
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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 &cDLSnR
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分页支持类: X]^FHYjhS
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java代码: @>Y.s6a
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package com.javaeye.common.util; {}r#s>
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import java.util.List; 0E*q-$P
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publicclass PaginationSupport { zX{O"w
97 Oi}
publicfinalstaticint PAGESIZE = 30; nQe^Bn
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privateint pageSize = PAGESIZE; ET t7?,x@
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privateList items; Af~>}-`a
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privateint totalCount; F E`4%X
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privateint[] indexes = newint[0]; ^|u7+b'|t
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privateint startIndex = 0; Lp!4X1/|\
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public PaginationSupport(List items, int
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t
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totalCount){ tM&O<6Y
setPageSize(PAGESIZE); ]>j>bHG
setTotalCount(totalCount); m=g\@&N
setItems(items); up(6/-/.7
setStartIndex(0); 7Cx*Ts $
} V*xo3hU
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public PaginationSupport(List items, int \<cs:C\h7
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totalCount, int startIndex){ .[%^~q7
setPageSize(PAGESIZE); UH8q:jOi
setTotalCount(totalCount); Y[_{tS#u
setItems(items); pD^7ZE6
setStartIndex(startIndex); WJ%4IaT
} Sn6cwf9.s
DC9\Sp?
public PaginationSupport(List items, int <1t.f}}uX
4b\R@Knu
totalCount, int pageSize, int startIndex){ d@sAB1:
setPageSize(pageSize); JQi+y;
setTotalCount(totalCount); UweXz.x7
setItems(items); QCm93YZs6E
setStartIndex(startIndex); "!-
} |hx"yy'ux
ld *W\
publicList getItems(){ h/'b(9fS
return items; CcGE4BB
} 9' $\GN{0
0m3:!#\
publicvoid setItems(List items){ mP!=&u fcU
this.items = items; kGz0`8URu
} s5`CV$bz
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publicint getPageSize(){ prIPPeMdz
return pageSize;
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} Th\w#%'N
@2yoy&IO
publicvoid setPageSize(int pageSize){ S*aVcyDEP
this.pageSize = pageSize; 6_G[&
} 71S~*"O0f
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publicint getTotalCount(){ *5e"suS2
return totalCount; ~__r-z
} g2Hz[C(
A7`+XqG
publicvoid setTotalCount(int totalCount){ 2F}D?]A
if(totalCount > 0){ ec8iZ8h8
this.totalCount = totalCount; M0jC:*D`"
int count = totalCount / =d+~l
1
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pageSize; %`]&c)Z
if(totalCount % pageSize > 0) G+_Q7-o&d6
count++; W"{:|'/v
indexes = newint[count]; QPD[uJ(I
for(int i = 0; i < count; i++){ `6No6.\J
indexes = pageSize * 8QJ^@|7
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i; =c-Y >
} /v <FH}
}else{ 0uZL*4A+C
this.totalCount = 0; {wp~
} +hIC N,8!
} eNHSfq
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publicint[] getIndexes(){
. r?URC
return indexes; {)CN.z:O
} T{CCZ"Fv
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publicvoid setIndexes(int[] indexes){ iQT$#"m
n
this.indexes = indexes; n<)gS7
} yQ [n7du
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publicint getStartIndex(){ ZwFVtR
return startIndex; ! %~P[;.
} Ye=c;0V(w
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publicvoid setStartIndex(int startIndex){ +A;AX.mr
if(totalCount <= 0) 6_=t~9sY
this.startIndex = 0; B4#XQ-
elseif(startIndex >= totalCount) P&snIJ
this.startIndex = indexes >h
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+|w%}/N
[indexes.length - 1]; m=4hi(g
elseif(startIndex < 0) ML!>tCT
this.startIndex = 0; 6)]zt
else{ |34M.YjA
this.startIndex = indexes 5/E7@h ,
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[startIndex / pageSize]; %a=^T?8
} nOm-Yb+F
} V[#$Sz[G
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publicint getNextIndex(){ K ; eR)
int nextIndex = getStartIndex() + Y00hc8<
/5wIbmz@I
pageSize; %.rVIc"
if(nextIndex >= totalCount) W<c95QD.
return getStartIndex(); |?gO@?KDZ
else N<N uBtkA
return nextIndex; NI^jQS
M]
} }2]m]D@%7
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publicint getPreviousIndex(){ &y+)xe:&S
int previousIndex = getStartIndex() - r.ib"W#4
4/N{~
pageSize; J=?P`\h
if(previousIndex < 0) 7L4~yazmK
return0; F&_b[xso7
else jU}iQM
return previousIndex; L!LhH
} V |hr 9
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} GlOSCJZ
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抽象业务类 dr gCr:Gf
java代码: x:E:~h[.^
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/** 2{9%E6%#
* Created on 2005-7-12 2]V&]s8Wi=
*/ DyCnL@
package com.javaeye.common.business; >9+h2B
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import java.io.Serializable; )qeed-{
import java.util.List; kKs}E| T
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import org.hibernate.Criteria; lcR1FbJ2'
import org.hibernate.HibernateException; jmJeu@(
import org.hibernate.Session; #/
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import org.hibernate.criterion.DetachedCriteria; *3A)s
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import org.hibernate.criterion.Projections; 6R|^IPOGp
import 5_[we1$P
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org.springframework.orm.hibernate3.HibernateCallback; *cy!PF&
import G0lg5iA<fC
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org.springframework.orm.hibernate3.support.HibernateDaoS 2o<aEn&7|e
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upport; 'pHxO,vo
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import com.javaeye.common.util.PaginationSupport; /_!Ed]
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public abstract class AbstractManager extends 0]Qk *u<
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HibernateDaoSupport { gXvE^fE
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privateboolean cacheQueries = false; R*l3 zn>
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privateString queryCacheRegion; Lk]W?
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publicvoid setCacheQueries(boolean f taa~h*
)?<V-,D
cacheQueries){ FyWrb+_0v
this.cacheQueries = cacheQueries; B&"c:)1
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} .W51Cup@&
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publicvoid setQueryCacheRegion(String Sv\399(
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queryCacheRegion){ @y/!`Ziw
this.queryCacheRegion = 'B;n&tJ
{.r
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queryCacheRegion; giHqc7-PaX
} ?>DwNz^.!
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publicvoid save(finalObject entity){ F13vc~$Ky
getHibernateTemplate().save(entity); ?D+H2[n\a
} w^^8*b<
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publicvoid persist(finalObject entity){ fbW<c`L H
getHibernateTemplate().save(entity); 30bdcDm,
} "J{A}g[
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publicvoid update(finalObject entity){ yJ*g ;
getHibernateTemplate().update(entity); Huc|HL#C
} Vx%!j&
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publicvoid delete(finalObject entity){ 3oMa
getHibernateTemplate().delete(entity); tR<L9h
} qHu\3@px
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publicObject load(finalClass entity, T:3}W0s,
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finalSerializable id){ %(B6eiA
return getHibernateTemplate().load ;umbld0
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(entity, id); P\%aJ'f~
} vT#m 8Kg
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publicObject get(finalClass entity, 7X8n|NZRH7
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finalSerializable id){ J@qwz[d i
return getHibernateTemplate().get Xb.#
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(entity, id); ,[[Xo;q
} 1IN^,A]r2h
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publicList findAll(finalClass entity){ N~%~Q
return getHibernateTemplate().find("from ^L-; S
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" + entity.getName()); #:=*n(GT
} ok{
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publicList findByNamedQuery(finalString s1J(-O
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namedQuery){ I\f\k>;
return getHibernateTemplate y'_2|5!Qs
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().findByNamedQuery(namedQuery); [bjP-pX
} aPin6L$;)
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publicList findByNamedQuery(finalString query, J+=?taZ
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finalObject parameter){ }tbZ[:T{K
return getHibernateTemplate |u.3Tp|3W
m}]\ ^$d
().findByNamedQuery(query, parameter); ~b})=7 n.
} ztC>*SX
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publicList findByNamedQuery(finalString query, )PvB^n
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finalObject[] parameters){ toel!+
return getHibernateTemplate 8@]vvZ2/gj
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().findByNamedQuery(query, parameters); ;O {"\H6
} [s F/sa3
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publicList find(finalString query){
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return getHibernateTemplate().find iZ 9ed]mf
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(query); ddEV@2F
} hs<OzM
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publicList find(finalString query, finalObject LzD,]{CC5
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parameter){ uHPd!#]
return getHibernateTemplate().find Hu"TEhW(2
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(query, parameter); R/kF,}^F
} *mkL>v &
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public PaginationSupport findPageByCriteria /|8/C40aY
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(final DetachedCriteria detachedCriteria){ .}n\c%&
return findPageByCriteria |9]_<X[ic
^=y%s
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Y``]66\Fp
} {Z#=ppvs
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public PaginationSupport findPageByCriteria \I 7,1I
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(final DetachedCriteria detachedCriteria, finalint Amv:dh
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startIndex){ ^<Zye>KO
return findPageByCriteria $t.M`:G
kNoS% ?1,
(detachedCriteria, PaginationSupport.PAGESIZE, )pG*_q
A }d\ND
startIndex); n7L|XkaQ
} g])iU9)8
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public PaginationSupport findPageByCriteria 0HDL;XY6
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(final DetachedCriteria detachedCriteria, finalint xo#K_"E
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pageSize, )^m"fQ+
finalint startIndex){ w-LaSJ(T
return(PaginationSupport) CM;B{*En
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getHibernateTemplate().execute(new HibernateCallback(){ iIc/%<
;
publicObject doInHibernate 41I2t(H @z
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(Session session)throws HibernateException { wS+j^
;"
Criteria criteria = -(9TM*)O
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detachedCriteria.getExecutableCriteria(session); >`I%^+z
int totalCount = HH|N~pBJB
5?8jj
((Integer) criteria.setProjection(Projections.rowCount ?4#wVzuzA
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()).uniqueResult()).intValue(); v>sjS3
criteria.setProjection U P*5M
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(null); @# GS4I
List items = nRcy`A%
6Tsi^((Li
criteria.setFirstResult(startIndex).setMaxResults \ %QA)T%
}B&+KO)
(pageSize).list(); 9ZI^R/*Kc
PaginationSupport ps =
#M|q}jA|
@Wa,
new PaginationSupport(items, totalCount, pageSize, 8p PQ
4f'!,Q ;
startIndex); OXF/4Oe
return ps; K/z2.Npn
} 8JU{]Z!G<;
}, true); [vOk=
} $~NB
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public List findAllByCriteria(final N[kl3h%q
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DetachedCriteria detachedCriteria){ o>A']+`Eu
return(List) getHibernateTemplate t4+bRmS`_
{2LV0:k2
().execute(new HibernateCallback(){ m3=Cg$n
publicObject doInHibernate [midNC +,
p']{WLDj2
(Session session)throws HibernateException { >9t+lr1
Criteria criteria = a"phwCc"%
0](V@F"~
detachedCriteria.getExecutableCriteria(session); 3z
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return criteria.list(); Xr{
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} K9) |b`E=
}, true); d)L,kzN
} G!7A]s>C
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public int getCountByCriteria(final ~9c jc
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DetachedCriteria detachedCriteria){ ,D\}DJ`)C
Integer count = (Integer) "=yz}~,
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getHibernateTemplate().execute(new HibernateCallback(){ &90pKs
publicObject doInHibernate W$:D#;jz`h
p/KG{-f,
(Session session)throws HibernateException { ]*<!|;q
Criteria criteria = ! l"*DR
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detachedCriteria.getExecutableCriteria(session); ()zn8_z
return duoM>B>8]
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criteria.setProjection(Projections.rowCount Pa"[&{ :
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()).uniqueResult(); '25zb+-
} <=@6UPsn2
}, true); Xw&vi\*m
return count.intValue(); CIAKXYM
} $>hH{
} ORFi0gFbA
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}[]1`2qD
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用户在web层构造查询条件detachedCriteria,和可选的 n\u3$nGL1`
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [S?`OF12
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PaginationSupport的实例ps。 Nl9}*3r
6yXN7L==x
ps.getItems()得到已分页好的结果集 ##'uekSJ
ps.getIndexes()得到分页索引的数组 | v:fP;zc
ps.getTotalCount()得到总结果数 4Q~++PKBe
ps.getStartIndex()当前分页索引 a@m
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ps.getNextIndex()下一页索引 :+%Yul
ps.getPreviousIndex()上一页索引 bM"d$tl$?'
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 l|fb;Giq=D
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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 Gg6<4T1
CW?R7A/
一下代码重构了。 -"}nm!j /5
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我把原本我的做法也提供出来供大家讨论吧: x{1S!A^
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首先,为了实现分页查询,我封装了一个Page类: 6{H@VF<QY!
java代码:
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/*Created on 2005-4-14*/ fn Pej?f:
package org.flyware.util.page; 5wbR}`8
q=;U(,Y
/** #fq&yjl#A
* @author Joa 6d;RtCENo
* '@WS7`@-y
*/ Je=k.pO1
publicclass Page { <UbLds{+Uo
h3MZLPe
/** imply if the page has previous page */ 1=mb2A
privateboolean hasPrePage; p
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7:n OAN}%
/** imply if the page has next page */ #Wely~
privateboolean hasNextPage; D}nIF7r2N
GyGF<%nq
/** the number of every page */ OVEQ^\Q5D
privateint everyPage; 6gB;m$:fV
U^&y*gX1
/** the total page number */ '(SqHP|8&g
privateint totalPage; ~[:C l
"T~A*a^
/** the number of current page */ 2(25IYMS8
privateint currentPage; ABU~V+'2
=[YjIWr#o
/** the begin index of the records by the current B0m2SUC,H
&cT@MV5
query */ `bjPOA(g
privateint beginIndex; CB>*(Mu
1.z]/cx<y
Jf@~/!m}'
/** The default constructor */ Zn]!*}
public Page(){ 9zlhJ7i
b@9d@@/wx
} Bu7aeBP
!z"nJC
/** construct the page by everyPage /C/I_S}H
* @param everyPage ?J28@rM
* */ YkI_i(
public Page(int everyPage){ hd#MV!ti
this.everyPage = everyPage; LteZ7e
} &'W ~~ir
oZw #]Q@
/** The whole constructor */ 8GT4U5c
;
public Page(boolean hasPrePage, boolean hasNextPage, PPj%.i)
Y9y'`}+
<MgC7S2I
int everyPage, int totalPage, LmjGU[L,@
int currentPage, int beginIndex){ $mut v=IO
this.hasPrePage = hasPrePage; U_@Dn[/:
this.hasNextPage = hasNextPage; D9higsN
this.everyPage = everyPage; Z6_fI
this.totalPage = totalPage; 9lc{{)m2)
this.currentPage = currentPage; Gr!@ih^
this.beginIndex = beginIndex; )m>Y[)8!
} \04(V'`U
_PGS"O?j
/** sQ8kLS_q8
* @return mC./,a[
* Returns the beginIndex. b^WF
R
*/ kB]*2o9-3
publicint getBeginIndex(){ b*<Fi#x1=
return beginIndex; ]ujXPK=t
} NJPp6RZ%
a5uBQ?
/** ]w~ECP(ap
* @param beginIndex ^d!I{ y#
* The beginIndex to set. #oxP,LR
*/ "eR-(c1
publicvoid setBeginIndex(int beginIndex){ Fqg*H1I[
this.beginIndex = beginIndex; (?#"S67
} N.q0D5 :
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/** tJ Mm
* @return }W5~89"
* Returns the currentPage. I$JyAj
*/ _E4_k%8y
publicint getCurrentPage(){ ;6{{hc4
return currentPage; s1
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} D@`"99z
.*nr3dY
/** {lN G:o
* @param currentPage _!^2A3c<
* The currentPage to set. Y>I9o)KR
*/ |snWO0iF
publicvoid setCurrentPage(int currentPage){ c<imqDf
this.currentPage = currentPage; z?.XVk-
} -e_B
jYnP)xX;
/** V( 3rTDg
* @return #hh7fE'9
* Returns the everyPage. & hv@ &
*/ (?kCo
publicint getEveryPage(){ !c=EB`<*
return everyPage; ]`TX%Qni
} o5< w2(
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/**
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* @param everyPage T)*tCp]
* The everyPage to set. Q6=>*}Cm6m
*/ \bv JZ_
publicvoid setEveryPage(int everyPage){ 8o[+>W
this.everyPage = everyPage; 9[Xe|5?c
} oZ!+._9
eNFZD1mS
/** qHC/)M#L
* @return xHWD1>
* Returns the hasNextPage. Tu-I".d+
*/ Wo<kKkx2
publicboolean getHasNextPage(){ :0(:}V3 z\
return hasNextPage; CC XOxd
} 1'SpJL1u~
)C%S`d<%,
/** tq2TiXo%
* @param hasNextPage -59;Zn/
* The hasNextPage to set. ; 8u5
*/ uEDvdd#V.
publicvoid setHasNextPage(boolean hasNextPage){ l8RKwECdPn
this.hasNextPage = hasNextPage; I0(nRu<
} VpWpC&
V; 1i/{
/**
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* @return iK9#{1BpML
* Returns the hasPrePage. y+P$}Nru
*/ {#H'K*j{
publicboolean getHasPrePage(){ 7` IO mTk
return hasPrePage; i2n66d
} `bcCj~j
c$~J7e6$
/** ~0Xx]
* @param hasPrePage zmh5x{US1
* The hasPrePage to set. <x\I*%(
*/ ?CZ*MMV
publicvoid setHasPrePage(boolean hasPrePage){ #4ii!ev
this.hasPrePage = hasPrePage; QS2~}{v
} ]hlYmT
}R)A%FKi@
/** 0j2M< W#
* @return Returns the totalPage. YveNsn
* 'cvc\=p
*/ 6|ENDd[
publicint getTotalPage(){ psB9~EU&Q
return totalPage; =pn(56
} }d 16xp
0A.9<&Lod
/** o3>D~9
* @param totalPage E?F?)!%
* The totalPage to set. T``~YoIdz
*/ -mqTlXM
publicvoid setTotalPage(int totalPage){ CB>O%m[1
this.totalPage = totalPage; i`" L?3T
} yMBFw:/o
o]m56
} BV6
U -
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;Ak 6*Sr
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 6%2\bI.#
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个PageUtil,负责对Page对象进行构造: O
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java代码: =-8y=
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/*Created on 2005-4-14*/ eHHqm^1z
package org.flyware.util.page; (vr
v-4
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import org.apache.commons.logging.Log; a$h
zG-
import org.apache.commons.logging.LogFactory; 6'QlC+E
j[\aGS7u
/** s14; \
* @author Joa XyE%<]
* qjVhBu7A
*/ iV8O<en&i
publicclass PageUtil { <[<]+r&*
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privatestaticfinal Log logger = LogFactory.getLog DF~{i{
lO dwH"
(PageUtil.class); TH#5j.uUs
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/** \A/??8cgXs
* Use the origin page to create a new page y/yg-\/XF
* @param page {B+{2;Zk
* @param totalRecords ICB'?yZ,
* @return qW'5Zk
*/ oEnCe
publicstatic Page createPage(Page page, int fDIKR[B
h@"u==0
totalRecords){ L$<(HQQJ8
return createPage(page.getEveryPage(), Fg-4u&Ik
a]8}zSUK
page.getCurrentPage(), totalRecords); {1]/ok2k5
} T^n0 =|
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/** $Y31YA
* the basic page utils not including exception u!K5jqP
=K\.YKT
handler e-/+e64Q@
* @param everyPage tA6x
* @param currentPage 3QO*1P@q
* @param totalRecords @8s:,Y_
* @return page BA cnFO
*/ {[Vkht}
publicstatic Page createPage(int everyPage, int E<
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currentPage, int totalRecords){ 0R[onPU_vZ
everyPage = getEveryPage(everyPage); )k'4]=d
<
currentPage = getCurrentPage(currentPage); @F,8M
int beginIndex = getBeginIndex(everyPage, gg%9EJpP
8ECBi(
currentPage); dqo&3^px
int totalPage = getTotalPage(everyPage, FW7@7cVoF
?v$kq}Rg
totalRecords); ~G*eJc0S:
boolean hasNextPage = hasNextPage(currentPage, /QK H30E
\" W_\&X
totalPage); u*i[A\Y
boolean hasPrePage = hasPrePage(currentPage); N
J_#;t#j
tyyfMA?'L;
returnnew Page(hasPrePage, hasNextPage, ww(.
everyPage, totalPage, <>|/U `
currentPage, L:3
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beginIndex); a}#Jcy!e
} !>Ru= $9
$2+(|VG4F
privatestaticint getEveryPage(int everyPage){ skRI\
return everyPage == 0 ? 10 : everyPage; #:6gFfk0<
} bEc @"^)
r%DaBx!x8
privatestaticint getCurrentPage(int currentPage){ jVhfpS[
return currentPage == 0 ? 1 : currentPage; =ijVT_|u0
} *)4`"D
voAen&>!
privatestaticint getBeginIndex(int everyPage, int s@c.nT%BYL
dN)!B!*aI
currentPage){ &!pG1Fp9
return(currentPage - 1) * everyPage; /,cyp.
} AD/7k3:
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privatestaticint getTotalPage(int everyPage, int jWL;ElM'
:Z'q1kW@"
totalRecords){ 4RYvI!
int totalPage = 0; ,V}Vxq3
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if(totalRecords % everyPage == 0) G8E=E<Yg~
totalPage = totalRecords / everyPage; r=o\!sh[
else FaUc"J
totalPage = totalRecords / everyPage + 1 ; :0)nL
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return totalPage; 6*92I
} ka$oUB)iQ
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privatestaticboolean hasPrePage(int currentPage){ +zup+=0e
return currentPage == 1 ? false : true; '7Aj0U(
} 31@m36? X
f/Q7WXl0
privatestaticboolean hasNextPage(int currentPage, IR<`OA
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int totalPage){ F;,LY:s|Z
return currentPage == totalPage || totalPage == V;}6C&aP.
OG&X7>'3I{
0 ? false : true; .oR_r1\y
} `LID*uD;_
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} Hlg Q0qb
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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。 $sX X6K),
Q[M?LNE`
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ~
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做法如下: "uthFE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 z]Jpvw`p
#*|0WaC
的信息,和一个结果集List: vid(^2+
java代码: kj4t![o+
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2]f"(X4jp
/*Created on 2005-6-13*/ xep!.k x
package com.adt.bo; %!;6h^@
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import java.util.List; tbP
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xN a Dzu"
import org.flyware.util.page.Page; ~!Q\\_
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/** !] -ET7
* @author Joa X+*"FKm S.
*/ l$s8O0-'T
publicclass Result { 'n)]"G|
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private Page page; [H!8m7i;
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private List content; 07?| "c.
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/** 3;h%mkKQ+
* The default constructor \D]H>i$
*/ qL03iV#h*V
public Result(){ G2{.Ew
super(); X~Yj#@
} 'Wn2+pd
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/** '*PJ-=G
* The constructor using fields *&\fBi]
* #)r
* @param page {J}Zv5
* @param content }gr6naz
*/ q-;z!iq|!
public Result(Page page, List content){ iw$n*1M
this.page = page; ;6?VkF
this.content = content; \R0&*cnmo
} a_pNFe
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/** BZP~m=kq
* @return Returns the content. PJCRvs|X
*/
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publicList getContent(){ i8tH0w/(M
return content; $g?`yE(K
} 3%JPJuNVw
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/** LJ+fZ
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* @return Returns the page. @\=%M^bx
*/ ^@&RJa-kb
public Page getPage(){ BpGK`0H
return page; UqP %S$9
} %e@Jc3
!/6`<eQ
`
/** TzCNY@y
* @param content m),3J4(q
* The content to set. BAq@ H8*B
*/ nEZoF
public void setContent(List content){ RK*ZlD<
this.content = content; dh~+0FZ{A
} tWNz:V
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/** 5jpb`Axj#
* @param page f/r@9\x
* The page to set. (mOUbO8
*/ O%(E 6
n
publicvoid setPage(Page page){ bOi`JJ^
this.page = page; {!B^nCSL
} aK%i=6j!
} m|RA@sY%`
p.gaw16}>
gX}(6RP_!
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\9*,[mvC
2. 编写业务逻辑接口,并实现它(UserManager, qw!_/Z3[
7,sslf2%K
UserManagerImpl) FE)L?
java代码: (5SN=6O
2VNMz[W'
v$O%U[e<
/*Created on 2005-7-15*/ \`|*i$
package com.adt.service; A&$oiLc
`g;`yJX<
import net.sf.hibernate.HibernateException; H)s$0Xd
3MR4yw5v
import org.flyware.util.page.Page; LM*#DLadk
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import com.adt.bo.Result; Kw%n;GFl'
Hw1<!Dyv
/** f$lf(brQ:
* @author Joa X676*;:!.
*/ -`mHb
publicinterface UserManager { 8?lp:kM
UqaLTdYG
public Result listUser(Page page)throws ::\7s
(W<n<sl:-
HibernateException; p+O2:
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} X]?qns7
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F 8\nAX
/$ 7_*4e
nyZUf{:
java代码: [jD.l;jF
pZu2[
pq"3)+3:
/*Created on 2005-7-15*/ ? jywW$
package com.adt.service.impl; <c[+60p"
#6[7q6{4
import java.util.List; ,&II4;F
!<wM?Q:
import net.sf.hibernate.HibernateException; +gG6(7&+=
V@0Z\&
import org.flyware.util.page.Page; QMGMXa
import org.flyware.util.page.PageUtil; S
C8r.
7b,5*]oZ
import com.adt.bo.Result; cxhS*"Ph
import com.adt.dao.UserDAO; oC]|ARgQk|
import com.adt.exception.ObjectNotFoundException; [@U2a$k+d
import com.adt.service.UserManager; vHY."$|H
6.z8!4fpl
/** e}u#:ysj
* @author Joa OPp>z0p%6X
*/ IK%fX/tDyc
publicclass UserManagerImpl implements UserManager { f^8,Z+n
p}qNw`
private UserDAO userDAO; C.r9)#G
2Uf}gG)
/** l@ +]XyLj
* @param userDAO The userDAO to set. \vBpH'hR,'
*/ #tyHj k
publicvoid setUserDAO(UserDAO userDAO){ U"} ml
this.userDAO = userDAO; mK3U*)A
} *(PQaXx4
{wWh;
/* (non-Javadoc) H7 acT
* @see com.adt.service.UserManager#listUser :I(-@2?{
$V$|"KRcs
(org.flyware.util.page.Page) Sm;EWz-?
*/ hadGF%> O6
public Result listUser(Page page)throws s6k,'`.
6~Y-bn"%D5
HibernateException, ObjectNotFoundException { sK~d{)+T
int totalRecords = userDAO.getUserCount(); &J~vXk:
!
if(totalRecords == 0) 2QUZAV\ Y
throw new ObjectNotFoundException eGrC0[SH
>gAq/'.Q
("userNotExist"); KmoPFlw
page = PageUtil.createPage(page, totalRecords); Xg|_
List users = userDAO.getUserByPage(page); s2t'jIB
returnnew Result(page, users); gf`uC0
} p&wXRI
S0V%JY;Gv
} VXforI
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zi~_[l-
)NeI]p
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 AP=mj
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询,接下来编写UserDAO的代码: 2.=3:q!H<%
3. UserDAO 和 UserDAOImpl: rA9BY :N@
java代码: (\
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dQ97O{O:i
KsM2?aqwf_
/*Created on 2005-7-15*/ i7:R4G(/#
package com.adt.dao; &DdFK.lt
|I7-7d-;/
import java.util.List; .aWEXJ
:]%z8,6k
import org.flyware.util.page.Page; ,bRvj8"M
_5I" %E;S
import net.sf.hibernate.HibernateException; }
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|
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/** 4ed+'-"m
* @author Joa %C*oy$.
*/ q^],K'
publicinterface UserDAO extends BaseDAO { yZ t}Jnv
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publicList getUserByName(String name)throws pqPhtWi%PJ
xXl^\?HC
HibernateException; k36%n
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publicint getUserCount()throws HibernateException; K29]B~0%E
B JDe1W3;'
publicList getUserByPage(Page page)throws 9.R)iA
@; ayl
HibernateException; w=Xil
nA%H`/O{
} Q7O8']~n
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GH2D5HVN
ai% fj*
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java代码: vKppXm1
1bb~u/jU
:.B};;N
/*Created on 2005-7-15*/ ]qCAog
package com.adt.dao.impl; +D|y))fE
uGl+"/uDu
import java.util.List; d_BO&k