Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 I!/EQO|
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 G!FdTvx$
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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 _h1bVd-
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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 @JSWqi>
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分页支持类: `*U@d%a
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java代码: gNr4oOR{
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package com.javaeye.common.util; OXLB{|hH80
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import java.util.List; <~|n}&
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publicclass PaginationSupport { u/W{JPlL
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publicfinalstaticint PAGESIZE = 30; 7b1
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privateint pageSize = PAGESIZE; TD\TVK3P
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privateList items; Yh]a4l0
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privateint totalCount; ta&z lZt
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privateint[] indexes = newint[0]; "0!#De
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privateint startIndex = 0; D?ic~-&
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public PaginationSupport(List items, int 5{-Hg[+9
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totalCount){ A]"6/Lr9P
setPageSize(PAGESIZE); *e ffDNE!
setTotalCount(totalCount); yMW3mx301j
setItems(items); -}@C9Ja[?
setStartIndex(0); ,%yC4
} Wda?$3!^q
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public PaginationSupport(List items, int ~JZLWTEe
eZ)
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totalCount, int startIndex){ CMC p7-v
setPageSize(PAGESIZE); GGHMpQ
setTotalCount(totalCount); <c@dE
setItems(items); 4P Sbr$
setStartIndex(startIndex); TFbc@rfB
} n}NUe`E_h
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public PaginationSupport(List items, int fCa
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totalCount, int pageSize, int startIndex){ '!X`X=
setPageSize(pageSize); pz2E+o
setTotalCount(totalCount); wB 8548C}-
setItems(items); =YYqgNz+\w
setStartIndex(startIndex); 2s2KI=6
} ^p4`o>
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publicList getItems(){ >CCy2W^W
return items; s,J\nbj0h
} f[zKA{R
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publicvoid setItems(List items){ |{MFo)
this.items = items; !h&h;m/c
} jhG6,;1zMI
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publicint getPageSize(){ pC4uar
return pageSize; fk^DkV^<
} 3Mh_&%!O
BI2'NN\
publicvoid setPageSize(int pageSize){ [e=k<gKH
this.pageSize = pageSize; &hpznIN
} D6_#r=08
OG IN-
publicint getTotalCount(){ 0Q%I[f8
return totalCount; eJOo~HIWQ
} uF,%N
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publicvoid setTotalCount(int totalCount){ Pw|/PfG
if(totalCount > 0){ Qm3RXO
this.totalCount = totalCount; On4Vqbks
int count = totalCount / 09Oe-Bg
Xa8_kv_
pageSize; @)ozgs@e
if(totalCount % pageSize > 0) ^-#:T
count++; vO{[P#L}
indexes = newint[count]; 1iY?t
for(int i = 0; i < count; i++){ Z_<Wr7D
indexes = pageSize * +DT
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i; 0} \;R5a<
} .R+n}>+K
}else{ Y$q--JA
this.totalCount = 0; .@(MNq{"6
} _#U hXXD
} z<"\I60Fe
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publicint[] getIndexes(){ kD+B8TrW
return indexes; XK
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} A-hWg;
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publicvoid setIndexes(int[] indexes){ Y%rC\Ij/i
this.indexes = indexes; MM+nE_9lV
} ~xZ)btf
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publicint getStartIndex(){ 4p u>f.
return startIndex; 0w^awT<$6
} {-c[w&q
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publicvoid setStartIndex(int startIndex){ wCr+/"t
if(totalCount <= 0) ~i@Z4tj7
this.startIndex = 0; (P:.@P~
elseif(startIndex >= totalCount) Jxb+NPUB
this.startIndex = indexes 'UCF2L
)vur$RX
[indexes.length - 1]; wmv/?g
elseif(startIndex < 0) Vzrp9&loY
this.startIndex = 0; .=b)Ae c
else{ EJrQ9"x&n
this.startIndex = indexes Q5v_^O<!
bO{wQ1)Z_
[startIndex / pageSize]; o@\q 6xl.
} mK7egAo
} ^nL_*+V`f
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publicint getNextIndex(){ $VE =sS.
int nextIndex = getStartIndex() + d 'wWj
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pageSize; H"g
p
if(nextIndex >= totalCount) ,e>N9\*
return getStartIndex(); (OK;*ZH+T@
else G0h7MO%x
return nextIndex; blB00
} n47v5.Wn
b{d@:"
publicint getPreviousIndex(){ t?kbN\,
int previousIndex = getStartIndex() - n|iO)L\9aB
~); 7D'[
pageSize; yX8$LOjE
if(previousIndex < 0) 5SY( :!
return0; VJ(#FA2
else w+owx(mN@
return previousIndex; #PRkqg+|
} Ih0kdi
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} <yrl_vl{
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抽象业务类 |q\:3R_0
java代码: a2un[$Jq`
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/** 6jtnH'E/
* Created on 2005-7-12 &P{[22dQ
*/ 5Y97?n+6
package com.javaeye.common.business; jz;"]k
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import java.io.Serializable; S2fBZ=V8
import java.util.List; 5 eWGX
A|d(5{:N
import org.hibernate.Criteria; Lm }:`
import org.hibernate.HibernateException; Fn!kest
import org.hibernate.Session; ebS>_jD
import org.hibernate.criterion.DetachedCriteria; !N1DJd
import org.hibernate.criterion.Projections; e'z[JG=
import wg=ge]E5
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org.springframework.orm.hibernate3.HibernateCallback; 3 tp'}v
import T/&4lJ^2l^
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org.springframework.orm.hibernate3.support.HibernateDaoS q>*+.~
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upport; @ zE>n
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import com.javaeye.common.util.PaginationSupport; q~=]_PMP
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public abstract class AbstractManager extends rBZ0(XSZQ
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HibernateDaoSupport { sc^TElic
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privateboolean cacheQueries = false; 58Fan*fO
&pD6Qq{
privateString queryCacheRegion; ]?`t
spm<t
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publicvoid setCacheQueries(boolean $>;U^- #3
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cacheQueries){ _$?SK id|o
this.cacheQueries = cacheQueries; (W|Eg
} @4D$Xl
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publicvoid setQueryCacheRegion(String RS~jHwIh
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queryCacheRegion){ !;^sIoRPV
this.queryCacheRegion = I7hE(2!$
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queryCacheRegion; 0BM3:]=wr
} )q\|f_
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publicvoid save(finalObject entity){ v'*#P7%Kf
getHibernateTemplate().save(entity); g,!6,v@
} 1#9 Q1@'OS
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publicvoid persist(finalObject entity){ spV/+jy{
getHibernateTemplate().save(entity); .R` {.~_{!
} #AzZ4<;7
2#:h.8
publicvoid update(finalObject entity){ 7W6tz\Y
getHibernateTemplate().update(entity); DDT)l+: XP
} $e7dE$eH
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publicvoid delete(finalObject entity){ V&E)4KBOs
getHibernateTemplate().delete(entity); EC2KK)=n}
} AAE8j.
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publicObject load(finalClass entity, Q&;dXE h
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finalSerializable id){ X/fk&Cp
return getHibernateTemplate().load F`;oe[wfk
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(entity, id); ++Qg5FukR
} Cyg\FHs
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publicObject get(finalClass entity, MMglo3
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finalSerializable id){ &
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return getHibernateTemplate().get 'Jww}^h1
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(entity, id); *wcb 5p
} o[W7'1O
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publicList findAll(finalClass entity){ ^<#08L;
return getHibernateTemplate().find("from _6"!y
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0!YB.=\{_q
" + entity.getName()); _4VF>#b
} G/Nb@pAy[
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publicList findByNamedQuery(finalString q[#2`
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namedQuery){ &{?*aK&%3l
return getHibernateTemplate sG`:mc~0
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().findByNamedQuery(namedQuery); ,lLkAd?q
} 4i>sOP3
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publicList findByNamedQuery(finalString query, 3zU!5tg
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finalObject parameter){ KPIc?|o/6
return getHibernateTemplate J fFOU!F\
7KOM,FWKe
().findByNamedQuery(query, parameter); p9ligs7V'
} >L F
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publicList findByNamedQuery(finalString query, &)@|WLW
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finalObject[] parameters){ $IzhaX
return getHibernateTemplate fGDR<t3yiQ
sf\p>gb
().findByNamedQuery(query, parameters); 47b=>D8
} g/&`NlD
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publicList find(finalString query){ m0+X 109
return getHibernateTemplate().find :|3n`,
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(query); _Gv[ D
} 7jIye 8Zi8
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publicList find(finalString query, finalObject $gU6=vN1#
}=CL/JHz
parameter){ ?z>7&
return getHibernateTemplate().find E? 1"&D
m
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(query, parameter); y%A!|aBu
} 1Uz sw
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public PaginationSupport findPageByCriteria v|:2U8YREf
] RgLTqv4x
(final DetachedCriteria detachedCriteria){ WV]%llj^
return findPageByCriteria ]]~tFdh
E^z\b *
(detachedCriteria, PaginationSupport.PAGESIZE, 0); E_-3G<rt
} >h+[#3vD
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public PaginationSupport findPageByCriteria V3j1M?>
ns|)VX
(final DetachedCriteria detachedCriteria, finalint )&R^J;W$M1
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startIndex){ \~|+*^e)
return findPageByCriteria qP6Yn JWl
q 65mR!)
(detachedCriteria, PaginationSupport.PAGESIZE, [jb3lO$Xa
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startIndex); 0!z@2[Pe66
} Soie^$
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public PaginationSupport findPageByCriteria bYz&P`o}
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(final DetachedCriteria detachedCriteria, finalint ~&\ f|%
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pageSize, x8;`i$
finalint startIndex){ '0$?h9"
return(PaginationSupport) H
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getHibernateTemplate().execute(new HibernateCallback(){ ExHKw~y9
publicObject doInHibernate IVlf=k
)
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(Session session)throws HibernateException { [~:-&
Criteria criteria = SWp1|.=Sm
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detachedCriteria.getExecutableCriteria(session); ogFKUD*h&>
int totalCount = x{NX8lN
z} '! eCl
((Integer) criteria.setProjection(Projections.rowCount " P)*FT
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()).uniqueResult()).intValue(); h7s;m
criteria.setProjection |[9?ma
&C>/L;
(null); 6<0n *&
List items = ;n\= R 5.
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criteria.setFirstResult(startIndex).setMaxResults s4_/&h
T32BnmB{
(pageSize).list(); vzF5xp.
PaginationSupport ps = 2xw6 5z
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new PaginationSupport(items, totalCount, pageSize, iYnEwAoN;
;,&8QcSVY
startIndex); &[2U$ `P`V
return ps; iJnU%
} uP\lCqK,
}, true); iqnJ~g
} /~4"No@
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public List findAllByCriteria(final b|SE<\
>:=|L%]s;\
DetachedCriteria detachedCriteria){ (;. AS
return(List) getHibernateTemplate -C#PQV
}HEvr)v9
().execute(new HibernateCallback(){ >zkRcm
publicObject doInHibernate @pGZLq
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(Session session)throws HibernateException { ::n;VY2&
Criteria criteria = qH"Gm
k`".
detachedCriteria.getExecutableCriteria(session); Gu=STb
return criteria.list(); q P ;A}C
} F_xbwa*=
}, true); #S%Q*k<hw
} 5 ,0d
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public int getCountByCriteria(final {b]aC
*/ G<!W
DetachedCriteria detachedCriteria){ |}){}or
Integer count = (Integer) 6io , uh!
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getHibernateTemplate().execute(new HibernateCallback(){ nS()u}c;r
publicObject doInHibernate U $Qv>7
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(Session session)throws HibernateException { ,fEO>
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Criteria criteria = Z -%(~
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detachedCriteria.getExecutableCriteria(session); LtT\z<bAI
return C1T_9}L-A
c62=* ] ,
criteria.setProjection(Projections.rowCount HaA1z}?n
= sAn,ri
()).uniqueResult(); p8wyEHB
} 2tayP@$
}, true); \b[9ebME
return count.intValue(); )a}"^1
} hzI*{
} 5=(c%
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用户在web层构造查询条件detachedCriteria,和可选的 +{>.Sk'$
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Q_lu`F|
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PaginationSupport的实例ps。 p$OD*f_b
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ps.getItems()得到已分页好的结果集 0VG=?dq
ps.getIndexes()得到分页索引的数组 )1z4q`
ps.getTotalCount()得到总结果数 O)<r>vqe}
ps.getStartIndex()当前分页索引 9".Uc8^p/F
ps.getNextIndex()下一页索引 8&Wx@QI
ps.getPreviousIndex()上一页索引 "Z9^}
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 %F3}/2
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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 Q<'@V@H
03"#J2b
一下代码重构了。 \(9p&"Q-
3;D?|E]1
我把原本我的做法也提供出来供大家讨论吧: a(Sv,@/
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首先,为了实现分页查询,我封装了一个Page类: Lw*1 .~
java代码: {{zua-F
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/*Created on 2005-4-14*/ TAAR'Jz S
package org.flyware.util.page; >C^/,/%v
0#
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/** P%jkKE?B4
* @author Joa ?1DUNZ6
* wz@/5c/u
*/ +9~ZA3DiP
publicclass Page { |0DP}
`~
pP
oxVvG{
/** imply if the page has previous page */ e5qvyUJM
privateboolean hasPrePage; {jUvKB_x
Ps |QW
/** imply if the page has next page */ "o<D;lO
privateboolean hasNextPage; _DrnL}9I7
y3AL)
/** the number of every page */ :+1bg&wQ
privateint everyPage; JOgmF_(>Z
SNxz*`@4
/** the total page number */ :7k`R62{
privateint totalPage; {Ot[WF
KMe.i'
/** the number of current page */ , Z4p0M
privateint currentPage; !r2}59J
=_pmy>_z
/** the begin index of the records by the current .Wh6(LDY(
Q%$i@JH`m
query */ M3PVixli3
privateint beginIndex; }kv) IJ
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/** The default constructor */ R>` ih&,)
public Page(){ 8|Q4-VK<!
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} JN)"2}SE
B
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/** construct the page by everyPage P$F#,Cn
* @param everyPage =^"~$[z(
* */ k~ZBJ+
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public Page(int everyPage){ dvxf lLd @
this.everyPage = everyPage; %!D_q~"H
} >Ziy1Dp
6J]~A0vsi}
/** The whole constructor */ V9gVn?O0
public Page(boolean hasPrePage, boolean hasNextPage, @eA %(C
mnQal>0~
vB]3Xb3a
int everyPage, int totalPage, vr<)Ay
int currentPage, int beginIndex){ W3aXW,P. V
this.hasPrePage = hasPrePage; 7kOE/>P?
this.hasNextPage = hasNextPage; Kl!DKeF
this.everyPage = everyPage; w# xncH:1
this.totalPage = totalPage; X #H:&*[!
this.currentPage = currentPage; c-v*4b/d
this.beginIndex = beginIndex; %oMWcgsdJi
} 4h(jw
zmdWVFVv
/** 7d%A1}Bq$
* @return ~ }Kp
* Returns the beginIndex. 0LZ=`tI
*/ $)4GCP
publicint getBeginIndex(){ )|MIWgfWN
return beginIndex; ;}n|,g>
} j#4+-
,K`E&hS
/** <tGI]@Nwk
* @param beginIndex #IbS
* The beginIndex to set. m`[oT\
*/ cYE./1D a
publicvoid setBeginIndex(int beginIndex){ 70d] d+M|
this.beginIndex = beginIndex; k{zs578h2
} Q|6Ls$'$
{/th`#o4b
/** (X0`1s
* @return $(Z]TS$M&
* Returns the currentPage. G* 8+h
*/ cA2^5'$$
publicint getCurrentPage(){ s0_-1VU
return currentPage; ab8oMi`z
} m*Q[lr=
Q@ykQ
/** L?AM&w-cg9
* @param currentPage -ryDsq
* The currentPage to set. Tyg$`\#
*/ /h1dm,
publicvoid setCurrentPage(int currentPage){ 8Pl+yiB/o`
this.currentPage = currentPage; w++B-_
} pjaiAe!k
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/** A73V6"
* @return GMVC&^
* Returns the everyPage. byEvc[/>Ys
*/ c13vEn!c
publicint getEveryPage(){ C.b,]7i
return everyPage; Dlqn~
} tjBh$)
|iLx $P6
/**
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* @param everyPage Ec7{BhH)
* The everyPage to set. !V$6+?2
*/ "#_)G7W+e
publicvoid setEveryPage(int everyPage){ jh<TdvF2$
this.everyPage = everyPage; qAS70XjOF
} &/J.0d-*``
)nf=eU4|
/** oi33{#%t
* @return UE}8Rkt
* Returns the hasNextPage. Jdk3)
\
*/ Zj%B7s1A
publicboolean getHasNextPage(){ l044c,AW(
return hasNextPage; BLl%D
} _QC?:mv6-
7/5NaUmPTt
/** U.zRIhA]
* @param hasNextPage _mIa8K;
* The hasNextPage to set. Uxj<x`<1x
*/ %J/fg<W1
publicvoid setHasNextPage(boolean hasNextPage){ "z{_hp{T^
this.hasNextPage = hasNextPage; ^g}gT-l%
} :,xyVb+
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/** }a #b$]Y
* @return .!7Fe)(x
* Returns the hasPrePage. $M}k%Z
*/ Ak%no3:9
publicboolean getHasPrePage(){ b@{%qh,C
return hasPrePage; 2|T|K?R^
} *_2O*{V
GY0XWUlC
/** oP43 NN~
* @param hasPrePage :Ul'(@
* The hasPrePage to set. I>YtWY|ed
*/ t5X G^3X@
publicvoid setHasPrePage(boolean hasPrePage){ $ g1wK}B3
this.hasPrePage = hasPrePage; s/W!6JX4
} >Rl0%!
EyKkjEXx_
/** 6ywnyh
* @return Returns the totalPage. onWYT} c{
* pAUfG^v
*/ +[X.-,yW
publicint getTotalPage(){ ,N))=/
return totalPage; 6\)8mK
} o1p$9PL\:
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/** Hm.&f2|(
* @param totalPage IDiUn!6Q
* The totalPage to set. gr[ "A
*/ .Y^d9.
publicvoid setTotalPage(int totalPage){ .NNcc4+
this.totalPage = totalPage; HiS,q0
} 9 :K
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} /q*Qx )y+1
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m&8U4uHN
[#,X$O>
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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 ?}1JL6mF{
l?yZtZ8
个PageUtil,负责对Page对象进行构造: EE{#S
java代码: )"i>R
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/*Created on 2005-4-14*/ @=MZ6q
package org.flyware.util.page; 6>LQGO
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import org.apache.commons.logging.Log; "x=@,*Bk
import org.apache.commons.logging.LogFactory; npG+#z
]'1N_m]?
/** 9>.<+b(>!'
* @author Joa ,,C~j`F
* 0N3tsIm>
*/ KOAz-h@6
publicclass PageUtil { XCqfAcNQ
=xlYQ}-(a
privatestaticfinal Log logger = LogFactory.getLog gR_b~^
hNR>Hy\
(PageUtil.class); yoA*\V
-;/@;W
/** A
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* Use the origin page to create a new page 33v%e
* @param page F|n$0vQ*
* @param totalRecords 9bzYADLI
* @return YiI:uG!|D
*/ v&CO#vK5.
publicstatic Page createPage(Page page, int fAY2V%Rft
[ ;3EzZL
totalRecords){ $.3CiM}~
return createPage(page.getEveryPage(), z*k3q`=>
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page.getCurrentPage(), totalRecords); z}b U\3!
} zOdasEd8!
hF=V
?\
/** Cn./N aq
* the basic page utils not including exception YRM6\S)py
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handler wJ]$'c3
* @param everyPage te)g',#lT
* @param currentPage xUYN\Pc-
* @param totalRecords ]K0,nj*\c
* @return page EK- bvZ
*/ <x%my4M
publicstatic Page createPage(int everyPage, int \Dsl7s=
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n
currentPage, int totalRecords){ ;KjMZ(Iil1
everyPage = getEveryPage(everyPage); ~E:/oV:4 >
currentPage = getCurrentPage(currentPage); .*wjkirF#~
int beginIndex = getBeginIndex(everyPage, dE9aE# o
cdU
>iB,
currentPage); 0 *Yivx6
int totalPage = getTotalPage(everyPage, PRf\6
MT#[ -M\
totalRecords); $Yj4&Two<
boolean hasNextPage = hasNextPage(currentPage, , }B{)
\iH\N/
totalPage); {#N,&?[
boolean hasPrePage = hasPrePage(currentPage); H<Zs2DP`
N&G;`
returnnew Page(hasPrePage, hasNextPage, 'XI-x[w
everyPage, totalPage, 7I0K=
'D7
currentPage, V^kl_!@
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beginIndex); IAd[_<9D
} PEMuIYm$
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privatestaticint getEveryPage(int everyPage){ V!f'
O@p[
return everyPage == 0 ? 10 : everyPage; COL_c<\
} <3 I0$?xL
~}Z'/zCZf
privatestaticint getCurrentPage(int currentPage){ r12e26_Ab
return currentPage == 0 ? 1 : currentPage; 2{01i)2 y
} ;HmQRiCg
^.>XDUO F
privatestaticint getBeginIndex(int everyPage, int S[y?>
TUi<
currentPage){ /mQ9}E4X
return(currentPage - 1) * everyPage; s;,ulME
} YH3[Jvzf4
=k2"1f~e
privatestaticint getTotalPage(int everyPage, int s x) x7
tC&jzN"
totalRecords){ |DUOyQ
int totalPage = 0; Es&'c1$^s
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if(totalRecords % everyPage == 0) Q oWjC
totalPage = totalRecords / everyPage;
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else 4EFP*7X
totalPage = totalRecords / everyPage + 1 ; &!?qSi~V
}4_c~)9Q
return totalPage; D n}TO*
} GE#LcCa
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privatestaticboolean hasPrePage(int currentPage){ (*G'~gSX
return currentPage == 1 ? false : true;
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} 8]&lUMaqVZ
98!H$6k
privatestaticboolean hasNextPage(int currentPage, `$>cQwB,D
+||[H)qym
int totalPage){ J
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return currentPage == totalPage || totalPage == 2KSt4oa
s/OXZ<C|
0 ? false : true; u`wT_?%w
}
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^ =RSoR
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} '?b.t2
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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。 ?v Z5 ^k
4.'KT;[_1/
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 V2*m/JyeB
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做法如下: 0u8(*?
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 5U.,iQ(d
)q'~<QxI\
的信息,和一个结果集List: uH8`ipX
java代码: .iH#8Z
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J!*Pg<
/*Created on 2005-6-13*/ Zq>}SR
package com.adt.bo; BXX1G
0= -D
import java.util.List; g#<M/qn
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import org.flyware.util.page.Page; P8;f^3V(+/
ot.R Gpg%
/** :]-? l4(%
* @author Joa 2s8(r8 AI
*/ 0%5x&vx'S
publicclass Result { jY5BVTWnV
\ /6m
private Page page; !FR1yO'd>
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private List content; t+BLO<
-g)*v<Fb5
/** ! jb{q bq
* The default constructor d^jIsE `
*/ Mq$Nra
public Result(){ ^Sz?c_<2P
super(); sYY=MD
} /yj-^u\R
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/** O"x/O#66
* The constructor using fields 1">]w2je:
* m1lfC
* @param page 9@|X~z5E
* @param content blA]z!FU
*/ L8j#lu
public Result(Page page, List content){ N^8
lfc$a
this.page = page; r&-Ir3[
this.content = content; hDs.4MZC`
} Kq`"}&0b\
!T3Esv
/** g_w4}!|
* @return Returns the content. s%~p?_P
*/ MF^I] 7_
publicList getContent(){ P=9Zm
return content; ^NTOZ0x~#
} =xX\z\[A
6">jf #pE
/** 'zhw]L;'g
* @return Returns the page. 0yxMIX
*/ 84*Fal~Som
public Page getPage(){ tr\Vr;zd
return page; !j.jvI%e;
} ;.r >
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/** weiqt
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* @param content _"`U.!3*
* The content to set. v#`Wf}G
*/ {1
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public void setContent(List content){ x 1"ikp}
this.content = content; =pS\gLQu
} 4GRmo"S
Y">;2Pt;
/** *ad"3>
* @param page \$h LhYz-
* The page to set. <P3r}|K
*/ ~!!>`x
publicvoid setPage(Page page){ -W+67@(\8H
this.page = page; w{"GA~=
} 1H_#5hd
} 9{bzxM
:[N[D#/z
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(dF4F4`{
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2. 编写业务逻辑接口,并实现它(UserManager, >9g` 9hB
pTK|u!fs
UserManagerImpl) TPds )osZT
java代码: )Oz( <vxw
K5)G+Id*
t=]&q.
/*Created on 2005-7-15*/ FZ/l
T-"
package com.adt.service; tH"SOGfSt
q'?:{k$%
import net.sf.hibernate.HibernateException; hqY9\,.C
${ ~UA6
import org.flyware.util.page.Page; 8E Y<^:
5 b[:B~J
import com.adt.bo.Result; aM9St!i
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/** `B6{y9J6
* @author Joa r Q'tab.,]
*/ v) q6
publicinterface UserManager { WU1o4&OF
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public Result listUser(Page page)throws Wx/!Myu
WJU`
g
HibernateException; j#U?'g
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} c+G: bb%p
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38Z"9
=3oz74O[
7-ba-[t#A
java代码: 9VN@M
h ;5
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+c\s%Gzrh
/*Created on 2005-7-15*/ vd /_`l.D
package com.adt.service.impl; KX)xCR~
4W.;p"S2
import java.util.List; %MP s}B
.tN)H1.:B
import net.sf.hibernate.HibernateException; 2>O2#53ls0
J6 [x(T
import org.flyware.util.page.Page; u ?g!E."v
import org.flyware.util.page.PageUtil; H8K<.RY
@\!wW-:A
import com.adt.bo.Result; 0 $e;#}
import com.adt.dao.UserDAO; z[v5hhI)4
import com.adt.exception.ObjectNotFoundException; Ai->,<Ig]
import com.adt.service.UserManager; ;^DUtr
;
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/** ,mYoxEB kl
* @author Joa !Y]}&pUP
*/ +ZE&]BO{
publicclass UserManagerImpl implements UserManager { <\^X,,WtO
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private UserDAO userDAO; YC=BP5^
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/** |7`Vw Z
* @param userDAO The userDAO to set.
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*/ M:`hb$k:
publicvoid setUserDAO(UserDAO userDAO){ 4Ro(r
sO
this.userDAO = userDAO; X=\#n-*
} C3@.75-E
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/* (non-Javadoc) r$v?[x>+K
* @see com.adt.service.UserManager#listUser [k'Ph33c
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(org.flyware.util.page.Page) <YeF?$S}
*/ :GK{JP
public Result listUser(Page page)throws j5'Jp}
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HibernateException, ObjectNotFoundException { )1fQhdO}x
int totalRecords = userDAO.getUserCount(); @L<[38
if(totalRecords == 0) DQlaSk4hF_
throw new ObjectNotFoundException b7AuKY{L
uaPBM<
("userNotExist"); Msd!4TrBJ
page = PageUtil.createPage(page, totalRecords); Km <Wh=
List users = userDAO.getUserByPage(page); GmL |7 6
returnnew Result(page, users); Y6L+3*Qt
} km c9P&
u=E?N:I~F
} i9!Urq-
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@i{JqHU"
ImV54h'
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 )b%c]!
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询,接下来编写UserDAO的代码: K%pmE?%,8
3. UserDAO 和 UserDAOImpl: #dpt=
java代码: Y$ChMf
z}Z`kq+C
7lVIN&.=
/*Created on 2005-7-15*/ :x{Q
package com.adt.dao; 68HX,t
{-Y_8@&