Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [kC-g @
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (<3'LhFII
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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 ux-Fvwoh
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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 D+"5R5J",
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分页支持类: .s,hl(w,
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java代码: mtJI#P
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package com.javaeye.common.util; oOJN?97!k
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import java.util.List; t;E-9`N
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publicclass PaginationSupport { =u73AM}
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publicfinalstaticint PAGESIZE = 30; L6U[H#3(
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privateint pageSize = PAGESIZE; 2:2rwH }e
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privateList items; 3pq&TYQU
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privateint totalCount; (wvDiW5
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n_
privateint[] indexes = newint[0]; #9p{Y}2#
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privateint startIndex = 0; [}d
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public PaginationSupport(List items, int ly6?jVJ
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totalCount){ f'R^MX2
setPageSize(PAGESIZE); WvNX%se]3
setTotalCount(totalCount); [)9bR1wh
setItems(items); DhkzVp_
setStartIndex(0); 7uxy<#Ar
}
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public PaginationSupport(List items, int ?u 9)
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totalCount, int startIndex){ !L-.bve!
setPageSize(PAGESIZE); J%D'Xlb
setTotalCount(totalCount); N.BD]_C
setItems(items); "hpK8vQ
setStartIndex(startIndex); ^vo^W:
} Fi(_A
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public PaginationSupport(List items, int --.: eFE/
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totalCount, int pageSize, int startIndex){ r~TiJ?8I
setPageSize(pageSize); lHz:Iibt
setTotalCount(totalCount); $ShL^g@
setItems(items); K'n^,
t
setStartIndex(startIndex); N$?mula
} j[) i>Qw
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publicList getItems(){ 5GT,:0
return items; op&,&
} 6$@Pk<w
f{WJM>$:
publicvoid setItems(List items){ 'Ys"yY@
this.items = items; L=4?vs
} o<@2zhuhrx
)v8;\1`s:
publicint getPageSize(){ *sB=Ys?
return pageSize; @wZ`;J %
} D@5&xd_@4
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publicvoid setPageSize(int pageSize){ [,|KVc=&H
this.pageSize = pageSize; 44RZk|U1J{
} 7Cp>i WV
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publicint getTotalCount(){ x-CYG?-x
return totalCount; (!DH'2I[
} !bT0kP$3}
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publicvoid setTotalCount(int totalCount){ R b\=\
if(totalCount > 0){ .l !:|Fd
this.totalCount = totalCount; qPH]DabpI
int count = totalCount / `S{< $:D
:[|`&_D9J
pageSize; ;oWh Tj`
if(totalCount % pageSize > 0) ^X"G~#v=q
count++; ;QREwT~H
indexes = newint[count]; J>]' {!+
for(int i = 0; i < count; i++){ 5j{o0&=_$
indexes = pageSize * 4x e:+sA.N
3,3{wGvHHW
i; h_*=_ 2|}
} Xdq2 .:\
}else{
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this.totalCount = 0; hLYSYMUb
} G*\wu&7!
} MvL%*("4b
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publicint[] getIndexes(){ D#W{:_f
return indexes; qSkt
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} iDp]lu
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publicvoid setIndexes(int[] indexes){ mK@\6GOMYP
this.indexes = indexes; &"Ua"H)
} v-42_}
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publicint getStartIndex(){ C&zgt
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return startIndex; (}gF{@sn
} (gl CTF9v
.<rL2`C[c
publicvoid setStartIndex(int startIndex){ vb{&T<
if(totalCount <= 0) V<:kS
this.startIndex = 0; <*2.B~
elseif(startIndex >= totalCount) gigDrf}
this.startIndex = indexes
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[indexes.length - 1]; e>uV8!u
elseif(startIndex < 0) vyN=X]p
this.startIndex = 0; T7Lk4cU
else{ V6BCW;
this.startIndex = indexes #++MoW}'g
k-b_
<Tbo|
[startIndex / pageSize]; _GI [SzD
} h"#^0$f
} =QRLKo#_
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publicint getNextIndex(){ 8
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int nextIndex = getStartIndex() + d3 fE[/oU
3M+hjc.
pageSize; vb5tyY0c
if(nextIndex >= totalCount) rQj.W6w=
return getStartIndex(); n KDX=73
else WTY{sq\'
o
return nextIndex; H.O7Y
} XZZ Ml
~Jmn?9 3
publicint getPreviousIndex(){ *2=:(OK
int previousIndex = getStartIndex() - !_l W#feR
c}g^wLa
pageSize; &P[eA u
if(previousIndex < 0) G80d!*7
return0; @~QW~{y
else DE."XSni
return previousIndex; Ks8S^77
} y5|`B(
WH/r$.&
} &wK%p/?
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抽象业务类 l')?w]|
java代码: LPO3B W
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/** f{^C+t{r
* Created on 2005-7-12 "eZNci
*/ }yx'U 3
package com.javaeye.common.business; S=eY`,'#R
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import java.io.Serializable; pWw aN4
import java.util.List; r,L#JR w#-
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import org.hibernate.Criteria; 7MOjZD4?
import org.hibernate.HibernateException; ,]y)Dy
import org.hibernate.Session; R l^ENrv!]
import org.hibernate.criterion.DetachedCriteria; )O#>ONm^
import org.hibernate.criterion.Projections; v?-pAA)ht
import BqCBH!^x
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org.springframework.orm.hibernate3.HibernateCallback; .v/s9'lB
import ;]KGRT
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org.springframework.orm.hibernate3.support.HibernateDaoS a^,6[
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upport; b@/z^k{%
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import com.javaeye.common.util.PaginationSupport; VbKky1a@
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public abstract class AbstractManager extends `~(KbH=]
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HibernateDaoSupport { m%qah>11
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privateboolean cacheQueries = false; x6.an_W6
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privateString queryCacheRegion; ,*bI0mFZ
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publicvoid setCacheQueries(boolean w`CGDF\Oo
t(\d;ybyx
cacheQueries){ K0g<11}(Yg
this.cacheQueries = cacheQueries; %K\_gR}V
} Y"K7$+5#\
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publicvoid setQueryCacheRegion(String rPv+eM">
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queryCacheRegion){ y9=/kFPRm
this.queryCacheRegion = f)({;,q
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queryCacheRegion; zX"@QB3E
} 38>8{Ma
;k9s@e#a
publicvoid save(finalObject entity){ Io|NL6[
getHibernateTemplate().save(entity); Y(m/E.h.~
} :cnH@:
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publicvoid persist(finalObject entity){ W&A22jO.1
getHibernateTemplate().save(entity); w5bD
} W&;X+XA_W
([qw#!;w;
publicvoid update(finalObject entity){ _WVeb}
getHibernateTemplate().update(entity); N*|Mfpf
} LrX7WI
d?$FAy'o5
publicvoid delete(finalObject entity){ %t([
getHibernateTemplate().delete(entity); `9(TqcE
} &y;('w
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publicObject load(finalClass entity, G[)Ll=
CSN]k)\N(
finalSerializable id){ K=;z&E=<c
return getHibernateTemplate().load JpvE c!cli
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(entity, id); 1 xm8w$%
} qSlC@@.>
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publicObject get(finalClass entity, P5yS`v$@
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finalSerializable id){ I8d#AVF2
return getHibernateTemplate().get vj]-p=
f]tc$`vb
(entity, id); ?\L@Pr|=Dr
} G'^Qi}o
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publicList findAll(finalClass entity){ th}Q`vg0
return getHibernateTemplate().find("from JK4vQWy
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" + entity.getName()); aze}koNE
} h.gj4/g
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publicList findByNamedQuery(finalString ftw\oGrS
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namedQuery){ y*0bHzJ
return getHibernateTemplate l ~kxt2&
'#mv- /<t*
().findByNamedQuery(namedQuery); 494"-F 6
} ak 94"<p
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publicList findByNamedQuery(finalString query, d#9
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S
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finalObject parameter){ 1K.i>]}>
return getHibernateTemplate )EZ#BF<0|
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().findByNamedQuery(query, parameter); JE9SPFQx9M
} ,_?P[~1
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publicList findByNamedQuery(finalString query, Bj5_=oo+d
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finalObject[] parameters){
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return getHibernateTemplate ejP273*ah
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().findByNamedQuery(query, parameters); tfW*(oU
} {WfZE&B
GY@(%^
publicList find(finalString query){ <RH2G
return getHibernateTemplate().find .21[3.bp/q
{}!`v%z
(query); @k~'b
} ]w ^9qS
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publicList find(finalString query, finalObject S?TyC";!
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parameter){ #Duz|F+%
return getHibernateTemplate().find iv@ey-,<
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(query, parameter); w$%d"Jm#X
} gbF^m`A>%+
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public PaginationSupport findPageByCriteria M{\W$xPL)
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(final DetachedCriteria detachedCriteria){ Z#w@ /!"}T
return findPageByCriteria QfqosoP\D
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k'(v
(detachedCriteria, PaginationSupport.PAGESIZE, 0); G1K72M}CW
} 5>{
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public PaginationSupport findPageByCriteria ?U3X,uv5J
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(final DetachedCriteria detachedCriteria, finalint (<y~]ig y
3@xn<eu
startIndex){ v 809/c*
return findPageByCriteria J~dk4D\
cO}`PD$i
(detachedCriteria, PaginationSupport.PAGESIZE, rO#WG}E<"
&,vPZ,7l
startIndex); <<a1a
} jpg$5jZ
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public PaginationSupport findPageByCriteria 19V
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(final DetachedCriteria detachedCriteria, finalint i n}N[
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pageSize, Ih_2")d
finalint startIndex){ ZV :cgv
return(PaginationSupport) ;fg8,(SM^
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getHibernateTemplate().execute(new HibernateCallback(){ *>b*I4dz
publicObject doInHibernate |Dz$OZP
c& &^Do
(Session session)throws HibernateException { HP`dfo~j
Criteria criteria = d5aG6/
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detachedCriteria.getExecutableCriteria(session); `R\aNgCS}
int totalCount = W ='c+3O6
V(/ @$&
((Integer) criteria.setProjection(Projections.rowCount \J@i:J6x$1
@(k}q3b<
()).uniqueResult()).intValue(); K
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criteria.setProjection {\HEUIa]w
}F v:g!
(null); kX0hRX
List items = '*`25BiQ
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criteria.setFirstResult(startIndex).setMaxResults x:Mh&dq?
ar+ j`QIe
(pageSize).list(); M|HW$8V3_2
PaginationSupport ps = :K-05$K
!|\$|m<n
new PaginationSupport(items, totalCount, pageSize, ]VuB2L[D
H]^hEQ3DT
startIndex); m{dXN=
return ps; i .O670D
} gL)l)}#
}, true); c/K:`XP~
} )sONfn
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public List findAllByCriteria(final nTG @=C#
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DetachedCriteria detachedCriteria){ Z4&,KrV
return(List) getHibernateTemplate mNc?`G_R
CtEpS<*c
().execute(new HibernateCallback(){ "L?h@8sa
publicObject doInHibernate [9hslk
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(Session session)throws HibernateException { BVJ6U[h`
Criteria criteria = (pDu
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detachedCriteria.getExecutableCriteria(session); %a'Nf/9=:
return criteria.list(); SC Qr/Q
} E}YJGFB7"
}, true); ~!t# M2Sk
} &1!T@^56
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public int getCountByCriteria(final 6k4ZzQ}
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DetachedCriteria detachedCriteria){ 6I<^wS9j_
Integer count = (Integer) 6bE~m<B\`
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getHibernateTemplate().execute(new HibernateCallback(){ )7e[o8O_6
publicObject doInHibernate t^=6czk
COx<X\
(Session session)throws HibernateException { N|,6<|
Criteria criteria = NC*h7
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detachedCriteria.getExecutableCriteria(session); b ;Vy=f
return :>Gm&w
(n
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jb,
criteria.setProjection(Projections.rowCount $Q[>v!!X
M~/%V NX
()).uniqueResult(); 0YsC@r47wL
} X^PR];V:$
}, true); f3 lKdXnP
return count.intValue(); w,\#)<boyb
} C} #:<Jx
} gJNp]I2R
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用户在web层构造查询条件detachedCriteria,和可选的 -Bqn^ E
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 1;p'2-x
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PaginationSupport的实例ps。 cH()Ze-B
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ps.getItems()得到已分页好的结果集 Q(-:)3g[aL
ps.getIndexes()得到分页索引的数组 $/%|0tQ
ps.getTotalCount()得到总结果数 eKlh }v
ps.getStartIndex()当前分页索引 zof>S>5>R7
ps.getNextIndex()下一页索引 klG]PUzd
ps.getPreviousIndex()上一页索引 c <[?Z7y
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~Dw.3P:-
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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 2G8f4vsC[
O $uXQ.r
一下代码重构了。 Zqke8q
m!s/L,iJJ
我把原本我的做法也提供出来供大家讨论吧: :]Jwcp
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首先,为了实现分页查询,我封装了一个Page类: 'vT
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java代码: y&NO[
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/*Created on 2005-4-14*/ 08&DP^NS
package org.flyware.util.page; r5z_{g
xtyzy@)QL
/** @cNX\$J
* @author Joa \+mc
* ;2
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*/ +2=N#LM
publicclass Page { 0[g8
t%<nS=u
/** imply if the page has previous page */ WC,&p
privateboolean hasPrePage; dV<|ztv
xt@zP)6G
/** imply if the page has next page */ @2-Eky
privateboolean hasNextPage; Sc;WraEn2
EoqUFa,
/** the number of every page */ 3!^5a%u
privateint everyPage; ,{A-<=6t
S+A'\{f
/** the total page number */ `/JJ\`Pu
privateint totalPage; %zQME6WELz
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/** the number of current page */ oop''6`C%
privateint currentPage; iIu
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/** the begin index of the records by the current 1 ry:Z2
3!&lio+<
query */ l2KR=&SX/
privateint beginIndex; $:w4_X5T
3}}~(
ncf=S(G+
/** The default constructor */ g4_DEBh
public Page(){ MjNCn&c
7%L%dyN
} @47MJzC
utKtxLX"
/** construct the page by everyPage AxLnF(eG
* @param everyPage 9'C kV [
* */ !Gsr* F{.
public Page(int everyPage){ :\x53-&hO4
this.everyPage = everyPage; Q^4j
} T1c2J,+}R
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/** The whole constructor */ gE]) z*tqX
public Page(boolean hasPrePage, boolean hasNextPage, X6%w6%su5
:ak D
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int everyPage, int totalPage, /~V.qisZ
int currentPage, int beginIndex){ U8kH'OD
this.hasPrePage = hasPrePage; h.FC:ym"
this.hasNextPage = hasNextPage; ?#ue:O1
this.everyPage = everyPage; l;zp f|.Vc
this.totalPage = totalPage; =XsdR?C
this.currentPage = currentPage; #+p30?r0y
this.beginIndex = beginIndex; ~,KAJ7O_
} ja*k\w{U'
5*~Mv<#
/** _XIls*6AK
* @return w~@.&
* Returns the beginIndex. HpXMPHd
*/ o<P@:}K
publicint getBeginIndex(){ Cd)e_&
return beginIndex; Srj%6rgsB
} p%e!&:!
;;'b;,/
/** 1\1a;Q3W%,
* @param beginIndex {Pm^G^EP
* The beginIndex to set. W Da;wt
*/ O @fX
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publicvoid setBeginIndex(int beginIndex){ ,t5X'sY L
this.beginIndex = beginIndex; GXB4&Q!C
} k7P~*ll$
Y W_E,A>h
/** -'+|r]
* @return *0M#{HQ
* Returns the currentPage. pv039~Sud
*/ UN_f2
publicint getCurrentPage(){ !J!zi
return currentPage; 2pFOC;tl
} K[)N/Q
lM Gz"cym
/** KY/}jJW
* @param currentPage +(3"XYh
* The currentPage to set. vai.",b=n6
*/ SPW @TF1
publicvoid setCurrentPage(int currentPage){ pWH8ex+
this.currentPage = currentPage; D4'"GaCv
} {"8\~r &b
p%Ae"#_X%
/** OqUEj 0X
* @return <K:?<F
* Returns the everyPage. %Bmi3
=Rr
*/ M x j
publicint getEveryPage(){ K1uN(T.Ju
return everyPage; w_G/[R3
} mH*42XC*
*2crhI*@>
/** uoFH{.)
* @param everyPage pr>Qu:
* The everyPage to set. K,tmh1
*/ AC ,$(E
publicvoid setEveryPage(int everyPage){ Vi`+2%4
this.everyPage = everyPage; #O]F5JB
} F0:Fv;
,0[8/)$M
/** |Z6rP-
* @return k#`.!yI,
* Returns the hasNextPage. #0`2wuo
{
*/ m}6GVQ'Q
publicboolean getHasNextPage(){ qfE/,L(B
return hasNextPage; srx`"
:
} N-jFA8n
dW;{,Q
/** J/w?Fa<
* @param hasNextPage gj\r>~S
* The hasNextPage to set. T2Cdw\
*/ $y\'j5nk3
publicvoid setHasNextPage(boolean hasNextPage){ nXK"B Ye
this.hasNextPage = hasNextPage; /fA:Fnv
} K>Fo+f
TWl':}
/** `j[)iok
* @return 65N;PH59D
* Returns the hasPrePage. QpS0iUG
*/ ^Ot+,l)
publicboolean getHasPrePage(){ s!Y>\3rMW
return hasPrePage; {"y{V
} Ts:dnGR5
wke$
/** :g'"*VXYB
* @param hasPrePage p}uL%:Vr
* The hasPrePage to set. 9+@_ZI-
*/ PmvTCfsg
publicvoid setHasPrePage(boolean hasPrePage){ INW8Q`[F
this.hasPrePage = hasPrePage; HYLU]9aH8
} =Z2U
s
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/** #g4X`AHB
* @return Returns the totalPage. ma~WJ0LM\
* dSsMa3X[n
*/ g-oHu8
publicint getTotalPage(){ Vj0`*nC)/
return totalPage; _zJY1cr
} %whPTc0P
/QHvwaW[
/** p(Y'fd}
* @param totalPage =4
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* The totalPage to set. .pu]21m=
*/ M=26@ n
publicvoid setTotalPage(int totalPage){ (BMFGyE3
this.totalPage = totalPage; @`$8rck`
} ~?E x?!\9R
RNcHU
} b,D+1'
i4'?/UPc
-78
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65=i`!f
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 3tS~/o+]
*<xEM-
个PageUtil,负责对Page对象进行构造: v)d\
5#7
java代码: F_zs"ex/
6~&4>2b0f
!(w\%$|
/*Created on 2005-4-14*/ MJ8z"SKnV
package org.flyware.util.page; 3Q~ng2Wv%
53=s'DZ
import org.apache.commons.logging.Log; wCkhE,#-_
import org.apache.commons.logging.LogFactory; 4ZQXYwfC|
wB?;3lTS
/** !R[o6V5T
* @author Joa 9W5vp:G
* lk%rE
*/ [jeZZB
publicclass PageUtil { .^l;3*X@
hR[Qdu6r
privatestaticfinal Log logger = LogFactory.getLog }a'8lwF%I
CcLP/
(PageUtil.class); i=o<\{iV:
tlCgW)<?
/** xx#;)]WT
* Use the origin page to create a new page ;I:jd")
* @param page `Q,moz
* @param totalRecords x
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2]~-
* @return SH<Nt[8C
*/ X@\rg}kP
publicstatic Page createPage(Page page, int lmp0Ye|
7$\;G82_
totalRecords){ c9= ;:E
return createPage(page.getEveryPage(), P,j)m\|
rKg5?.
page.getCurrentPage(), totalRecords); 2Af1-z^^K
} wx>BNlT@?
ES(b#BlrP/
/** b=wc-nA
* the basic page utils not including exception -Z-|49I/mN
$eCxpb..
handler eXc`"T,C.
* @param everyPage f]qPxRw
* @param currentPage /Pxt f~$
* @param totalRecords 6*lTur9ni
* @return page T5=3 jPQ
*/ O<
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publicstatic Page createPage(int everyPage, int
ry*b"SO
(ye1t96
currentPage, int totalRecords){ P@`@?kMU
everyPage = getEveryPage(everyPage); O8wR#(/
currentPage = getCurrentPage(currentPage); 4@u*#Bp`|
int beginIndex = getBeginIndex(everyPage, XPBKQm_}
,j:`yB]4,
currentPage); X"z^4?Aj+
int totalPage = getTotalPage(everyPage, Q=)$
MXh0 a@*]
totalRecords); `%ZM(9T
boolean hasNextPage = hasNextPage(currentPage, `k+ci7;
k-Hy>5;
totalPage); _rdEur C6
boolean hasPrePage = hasPrePage(currentPage); NoB)tAvw
1aP3oXLL
returnnew Page(hasPrePage, hasNextPage, j_H9l,V
everyPage, totalPage, <~X4&E]rT_
currentPage, tda#9i[pkH
1Mn=m w
beginIndex); J/mLmSx
} 7?9QlUO
bBk_2lg=4)
privatestaticint getEveryPage(int everyPage){ 93Kd7x-3
return everyPage == 0 ? 10 : everyPage; "oz
: & #+
} r7+"i9
LUc!a4i"fO
privatestaticint getCurrentPage(int currentPage){ sG7G$G*ta!
return currentPage == 0 ? 1 : currentPage; mEeD[dMN
} s;Q0
O{R)0&
privatestaticint getBeginIndex(int everyPage, int $REz{xgA=
mhVdsa
currentPage){ 6hp>w{+
return(currentPage - 1) * everyPage; L{1MyR7`I+
} :%7y6V*
`yJ3"{uO
privatestaticint getTotalPage(int everyPage, int 4zKmoYt
;l`us
totalRecords){ + -~8t^
int totalPage = 0; KG<. s<
6i'GM`>w
if(totalRecords % everyPage == 0) xl2;DFiYt
totalPage = totalRecords / everyPage; O/Cwm;&t
else D=1:-aLP7
totalPage = totalRecords / everyPage + 1 ; #0$fZ
CGw, RNV
return totalPage; c||EXFS}O
} e_=TkG1E6
c(Ws3
privatestaticboolean hasPrePage(int currentPage){ =D;n#n 7
return currentPage == 1 ? false : true; =d`w~iC
} )hG4,0hv&
|ht:_l
8
privatestaticboolean hasNextPage(int currentPage, Z<D8{&AjS
tE'^O<
K
int totalPage){ tVQq,_9C
return currentPage == totalPage || totalPage == "`Q&s
f[}(E
0 ? false : true; .>#X *u
} Sf*1Z~P|
VOJA}$
6mV-+CnYC
} Mc,3j~i
gcF:/@:Rm
z@I'Ryalyc
PH.g+u=v
e dTFk$0
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。 +[vIocu
=j~BAS*"
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 7+9o<j@@o
9U>OeTh(
做法如下: _mWVZ1P
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 'uC=xG.*}
]A%]W ^G
的信息,和一个结果集List: p<[MU4
java代码: 60TM!\
GJ5R <f9I
Upa F>,kM
/*Created on 2005-6-13*/ (^oN, 7
package com.adt.bo; BItH0r7
>{S
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import java.util.List; j*\oK@
iC{(vL0P+
import org.flyware.util.page.Page; 5Q;Q
fUMjLA|*I<
/** n:|a;/{I]9
* @author Joa v%rmfI U
*/ FI,K 0sO/|
publicclass Result { %oB0@&!mS
sZI"2[bk
private Page page; EHy 15RL
kXV;J$1
private List content; 4a0Ud !Qcs
E{0e5. {
/** <6Y|vEo!N
* The default constructor D6~KLSKm
*/ yAAV,?:o[
public Result(){ "cyRzQ6EH
super(); NN#k^[i1
} Zs(BViTb|
Nw9@E R
/** lz!(OO,g
* The constructor using fields _&~l,%)&
* 0BNH~,0u
* @param page tm/=Oc1p
* @param content F?$Vx)HI
*/ Fv7]1EO.
public Result(Page page, List content){ k-H6c
this.page = page; fF(AvMsO
this.content = content; #]dq^B~~
} #K0/ >W
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/** X{Fr
* @return Returns the content. O&MH5^I
*/ m62Zta
publicList getContent(){ (kVY\!UAt
return content; O}%ES AB
} ~;jgl_5?b
tmOy"mq67
/** TFG?
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* @return Returns the page. -. o,bg
*/ bfpeK>T
public Page getPage(){ (u^8=#
return page; JN:L%If
} Ux1j +}y
*Lxt{z`9
/** YzQ(\._s
* @param content z{&Av
* The content to set. xe^M2$clb\
*/ |{(JUXo6K
public void setContent(List content){ !yT=*Cj4
this.content = content; _p0gXb1m`
} f,i2U|1pbj
.71ZeLv*
/** .rG~\Ws
* @param page qE3Ud:j
* The page to set. @54$IhhT~
*/ fPHV]8Ft|
publicvoid setPage(Page page){ M*bsA/Z
this.page = page; NC!B-3?x
} O'B3s y
} 4CchE15
<{8x-zbR+
pY-!NoES
9od c :
\BH?GMoP
2. 编写业务逻辑接口,并实现它(UserManager, :%33m'EV}
wh8;:<|
UserManagerImpl) p>kny?AJ
java代码: zRmVV}b
%]Nm'"Y`U
&>+5
8
/*Created on 2005-7-15*/ y`8U0TE3R
package com.adt.service; w)* H&8h@
4"Qb^y
import net.sf.hibernate.HibernateException; fd #QCs
n 7B2rRJH
import org.flyware.util.page.Page; M@7U]X$g
<$hv{a
import com.adt.bo.Result; 6W
Nt_sV7zzb
/** k&:q|[N
* @author Joa /2E
Q:P
*/ bf=\ED ^
publicinterface UserManager { #g@4c3um|
a#+$.e5
public Result listUser(Page page)throws wSCI?
h5T~dGRlR
HibernateException; -hfkF+=U'
sr[[xzL
} sw}^@0ua=
p<h(
<&`Rf6
8dLmsk^
-IVWkA)7
java代码: #@w/S:KbJt
ReD]M@;
%-$
:/N
/*Created on 2005-7-15*/ },}g](!m
package com.adt.service.impl; T`j{2
G9xO>Xp^Al
import java.util.List; k >.U !
Avyer/{
import net.sf.hibernate.HibernateException; =Ez@kTvOs
!mWm@}Ujg
import org.flyware.util.page.Page; _qk&W_u
import org.flyware.util.page.PageUtil; =aQlT*n%3
|;(P+Q4lB
import com.adt.bo.Result; uVhzJu.
import com.adt.dao.UserDAO; nO'C2)bBSG
import com.adt.exception.ObjectNotFoundException; -qvMMit%7
import com.adt.service.UserManager; IY[qWs
8 l= EL7
/** .waj.9&[l
* @author Joa 9 `bLQd
*/ MK!
@ND
publicclass UserManagerImpl implements UserManager { )+Z.J]$O-
@c"s6h&
private UserDAO userDAO; C|g1:#0
P_mP ^L
/** \kY:|T
* @param userDAO The userDAO to set. 3}3b@: <
*/ Voq/0,d
publicvoid setUserDAO(UserDAO userDAO){ ps8tr:T^=
this.userDAO = userDAO; 9vW]HOK
} kef%5B
9mn~57`y
/* (non-Javadoc) g] ]6) nT
* @see com.adt.service.UserManager#listUser %qE"A6j
=\oW{?
(org.flyware.util.page.Page) ez%:>r4
*/ ob9od5Rf
public Result listUser(Page page)throws 5 A5t
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HibernateException, ObjectNotFoundException { Qi=0[
int totalRecords = userDAO.getUserCount(); _*{Lha
if(totalRecords == 0) 8'qlg|{!~
throw new ObjectNotFoundException 3fX_XH1Q
R47y/HG,
("userNotExist"); XhWo~zh"
page = PageUtil.createPage(page, totalRecords); Pf?&ys6
List users = userDAO.getUserByPage(page); 5 b,|6
returnnew Result(page, users); iPG:w+G
} ]mNsG0r6
L})*ck
} SD8>,
=b1
y*?
9`VY)"rJ
%z-s o?gF
2>9..c
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 M$>Nd6,@N
g3Hi5[-H
询,接下来编写UserDAO的代码: *A}td8(
3. UserDAO 和 UserDAOImpl: \h0+`
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java代码: pzQc UG
KjF8T7%
iyUnxqP
/*Created on 2005-7-15*/ =`N 0
package com.adt.dao; :ec>[N~KG
:=!6w
import java.util.List; k
7@:e$7
QK #qW-49O
import org.flyware.util.page.Page; ni )G
RF
-c`C
import net.sf.hibernate.HibernateException; 8ql<7RTM!
t.O~RE
/** $$Ibr]$5
* @author Joa T?jN/}qg
*/ $/(``8li_
publicinterface UserDAO extends BaseDAO { 9a sA-'fZ
d>#X+;-k
publicList getUserByName(String name)throws l>BM}hS
K *1]P ar;
HibernateException; **AkpV)
LL+_zBP.
publicint getUserCount()throws HibernateException; Hl{ul'o
n<b}6L}
publicList getUserByPage(Page page)throws ,qV 7$u
UdpuQzV<4`
HibernateException; ;j<#VS-]
ArT@BqWd
} p@@*F+
scE#&OWF%
sv6m)pwh
q1rD>n&d
ow'CwOj$
java代码: _+Pz~_+kS
&IG*;$c!
y (%y'xBP
/*Created on 2005-7-15*/ Jgq#m~M6
package com.adt.dao.impl; 0R-W9qP
bq}`jP~#
import java.util.List; ;2gO(
1>bNw-kz7
import org.flyware.util.page.Page; +'[/eW
e=[@HVr
import net.sf.hibernate.HibernateException; {]4Zpev
import net.sf.hibernate.Query; Y7')~C`up^
"z*?#&?,
import com.adt.dao.UserDAO; !2.eJ)G
"=2'O qp1
/** #w!ewC vt
* @author Joa {=MRJg!U
*/ T#&