Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 1tJg#/?
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 #!9S}b$
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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 xxm%u9@s
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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 $&=p+
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分页支持类: Hh4 n
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java代码: `g_"GE
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package com.javaeye.common.util; {66fG53x
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import java.util.List; 8`]=C~G
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publicclass PaginationSupport { Y9=(zOqv
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publicfinalstaticint PAGESIZE = 30; o%4Gd~
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privateint pageSize = PAGESIZE; jr /lk
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privateList items; O Lc}_
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privateint totalCount; zi'Jr)n
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privateint[] indexes = newint[0]; $x#FgD(iI
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privateint startIndex = 0; H3H_u4_?SE
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public PaginationSupport(List items, int NJ MJ
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totalCount){ gUAxyV
setPageSize(PAGESIZE); v`c$!L5
setTotalCount(totalCount); 8*SP~q
setItems(items); 3^StIw{X
setStartIndex(0); $3d}"D
} PU {uE[
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public PaginationSupport(List items, int id?#TqD
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totalCount, int startIndex){ FkqQf8HB
setPageSize(PAGESIZE); ^#):c`
setTotalCount(totalCount); vMs;>lhtg
setItems(items); ,WQ^tI=O
setStartIndex(startIndex); 2`a
q**}
} SMf+qiM-E
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public PaginationSupport(List items, int `T2 <<<
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totalCount, int pageSize, int startIndex){ +y#T?!jQYj
setPageSize(pageSize); W0zbxJKjd
setTotalCount(totalCount); }K(o9$V ^!
setItems(items); UzKFf&-:;K
setStartIndex(startIndex); f{lZKfrp
} MDRe(rF=
)B!d,HKt;
publicList getItems(){ A
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return items; 70B)|<$
} XTeb9h)3
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publicvoid setItems(List items){ ;50_0Mv;(:
this.items = items; _J]2~b
} *zWWmxcJa
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publicint getPageSize(){ a45ss7
return pageSize; ^# A.@
} }E}8_8T6
Y& ] 8 {
publicvoid setPageSize(int pageSize){ ?G08[aNR
this.pageSize = pageSize; 7@PIM5h
} [<wbbvXR
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publicint getTotalCount(){ 8V$3b?]
return totalCount; L7mz#CMWf
} eX2<}'W<
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publicvoid setTotalCount(int totalCount){ Iia.k'N
if(totalCount > 0){ CiL94Nkd9
this.totalCount = totalCount; !RlC~^
-
int count = totalCount / M8@_Uj
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pageSize; cgj.e
if(totalCount % pageSize > 0) s(&;q4|
count++; #vf_D?^
indexes = newint[count]; l#@&~f[
for(int i = 0; i < count; i++){ p8, 0lo
indexes = pageSize * cX
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} 2 [!Mx&^
}else{ &!y]:CC{
this.totalCount = 0; kDB iBNdB
} m]IysyFFK
} !Zbesp KZ
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publicint[] getIndexes(){ 2 Y|D'^
return indexes; ,vG<*|pn
} :+,st&(E
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publicvoid setIndexes(int[] indexes){ IbWPlbH
this.indexes = indexes; +#]|)VZ
} EX?h0Uy
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publicint getStartIndex(){ *+8%kn`c
return startIndex; i~& c|
} K@@9:T$
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publicvoid setStartIndex(int startIndex){ ggou*;'
if(totalCount <= 0) !%mi&ak(Rn
this.startIndex = 0; W>L@j(
elseif(startIndex >= totalCount) =p&sl;PsLw
this.startIndex = indexes 4w{-'M.B
Yb=6C3l@
[indexes.length - 1]; Lm.`+W5
elseif(startIndex < 0) V2yveNz\7
this.startIndex = 0; [[qwaI
else{ eO{@@?/y
this.startIndex = indexes 67J*&5? |
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[startIndex / pageSize]; 2z983^
} 4YJ=q% G
} jNy?[
)
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publicint getNextIndex(){ Q[s2}Z!N;
int nextIndex = getStartIndex() + +$(0w35V5
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pageSize; )o8g=7Jm
if(nextIndex >= totalCount) ">6&+^BN'
return getStartIndex(); *?8RXer
else `)[dVfxA
return nextIndex; abZdGnc
} (5;D7zdA
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publicint getPreviousIndex(){ V:\]cGA{
int previousIndex = getStartIndex() - 8Inx/>eOI
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pageSize; 5
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if(previousIndex < 0) KzkgWMM
return0; 93I'cWN
else 55hyV{L%
return previousIndex; GOW"o"S
} +{6`F1MO
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} :l~E E!
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抽象业务类 C6)R#
java代码: z{6YC~
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/** l#6&WWmr
* Created on 2005-7-12 9d"5wx
*/ l^,qO3ES
package com.javaeye.common.business; aRKv+{K
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import java.io.Serializable; Wy(pLBmb
import java.util.List; g9qC{xd
_j 5N=I{U
import org.hibernate.Criteria; sPpS~wk*
import org.hibernate.HibernateException; nx;$dxx_Ws
import org.hibernate.Session; 9-G b"hr
import org.hibernate.criterion.DetachedCriteria; aQmfrx
import org.hibernate.criterion.Projections; =xBT>h;
import +=,u jO:
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org.springframework.orm.hibernate3.HibernateCallback; =yh3Nd:u
import ( 2zeG`
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org.springframework.orm.hibernate3.support.HibernateDaoS p1
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cno;>[$
upport; u0BMyH
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import com.javaeye.common.util.PaginationSupport; 9>{t}Id
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public abstract class AbstractManager extends 3`rIV*&_{
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HibernateDaoSupport { >i`8R
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privateboolean cacheQueries = false; gV.f*E1C
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privateString queryCacheRegion; SW;HjQ>V
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publicvoid setCacheQueries(boolean (0g7-Ci
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cacheQueries){ 9ET/I$n
this.cacheQueries = cacheQueries; G)~MbesJ
} :;_#5
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publicvoid setQueryCacheRegion(String QmHwn)Ly
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queryCacheRegion){ 'f6PjI
this.queryCacheRegion = /B=l,:TnJ
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queryCacheRegion; IW] *i?L
} a`SQcNBf*
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publicvoid save(finalObject entity){ 96W!~w2xx
getHibernateTemplate().save(entity); xDRNt Lj<u
} w7n6@"q
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publicvoid persist(finalObject entity){ M7D@Uj&xx(
getHibernateTemplate().save(entity); ]7H ?
} &S\q*H=}i
@WcK<Qho
publicvoid update(finalObject entity){ (W*~3/@D
getHibernateTemplate().update(entity); {\tHS+]
} ^A9D;e6!-
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publicvoid delete(finalObject entity){ Z7 \gj`
getHibernateTemplate().delete(entity); zk)9tm;i{
} Q_p!;3
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publicObject load(finalClass entity, v0pyyUqS
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finalSerializable id){ \etuIFQ#U
return getHibernateTemplate().load hD OEJ
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(entity, id); S;0,UgB1
} RRYm.dMIw
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publicObject get(finalClass entity, 8<z]rLQw?%
}(}+I}&~
finalSerializable id){ zj G>=2
return getHibernateTemplate().get We^!(G
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(entity, id); M>Yge~3
} k_A. aYe
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publicList findAll(finalClass entity){ dWC[p
return getHibernateTemplate().find("from Z1V%pg>]*
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" + entity.getName()); hY5G=nbO*
} VUfV=&D-*g
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publicList findByNamedQuery(finalString Q4YIKNN|7
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namedQuery){ -#yLH
return getHibernateTemplate eK
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().findByNamedQuery(namedQuery); YuO-a$BP
} JXR_klx
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publicList findByNamedQuery(finalString query, $`J'Y>`
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finalObject parameter){ ZzDE
return getHibernateTemplate 7C7eXJ9q
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().findByNamedQuery(query, parameter); )"j)9RQ}
} fX)C8J^=G
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publicList findByNamedQuery(finalString query, k0;N D
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finalObject[] parameters){ 76i)m!
return getHibernateTemplate Nr.maucny
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().findByNamedQuery(query, parameters); CTu#KJ?j
} }F=+*-SYZ
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publicList find(finalString query){ &@E{0ZD
return getHibernateTemplate().find 5<-_"/_
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(query); j~+<~2%c
} > UT Ak
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publicList find(finalString query, finalObject l#8SlRji
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parameter){ w#v8a$tT
return getHibernateTemplate().find Z
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(query, parameter); oObm5e*Z
} x,W)qv
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public PaginationSupport findPageByCriteria E}U[VtaC
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(final DetachedCriteria detachedCriteria){ $ t' .
return findPageByCriteria &V;^xMO!
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ,Y~{RgG
} v3 $+l1
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public PaginationSupport findPageByCriteria U1?*vwfKZ
; z_ZZ(W
(final DetachedCriteria detachedCriteria, finalint \RcB,?OK
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startIndex){ R:+2}kS5e{
return findPageByCriteria ]w!gv
/;
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(detachedCriteria, PaginationSupport.PAGESIZE, 3`@alhD'
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startIndex); KjR^6v
} FYIzMp.4
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public PaginationSupport findPageByCriteria ]"SH
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(final DetachedCriteria detachedCriteria, finalint %mR roR6
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pageSize, =ogzq.+|
finalint startIndex){ e%VJ:Dj
return(PaginationSupport) <b74L
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getHibernateTemplate().execute(new HibernateCallback(){ =j[zMO
publicObject doInHibernate 4am`X1YV#
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(Session session)throws HibernateException { rM6^pzxe
Criteria criteria = (g2?&b
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detachedCriteria.getExecutableCriteria(session); $x&@!/&|pv
int totalCount = *@'4 A :A
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((Integer) criteria.setProjection(Projections.rowCount b#p)bcz!I
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()).uniqueResult()).intValue(); /E'c y
criteria.setProjection h?wNmLre
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(null);
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List items = #W#GI"K
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criteria.setFirstResult(startIndex).setMaxResults aVv$k
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(pageSize).list(); $Xf1|!W%a%
PaginationSupport ps = 6x KbK1W
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new PaginationSupport(items, totalCount, pageSize, et";*EZJX
,<$6-3sC-
startIndex); ;2"#X2B
return ps; l1^/Q~u
} t59"[kQ
}, true); @
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} loVUB'OSv
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public List findAllByCriteria(final a
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DetachedCriteria detachedCriteria){ 910Ym!\{:
return(List) getHibernateTemplate O[Xl*9P
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().execute(new HibernateCallback(){ O@[c*3]e
publicObject doInHibernate LjUBV_J
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(Session session)throws HibernateException { =E Cw'
Criteria criteria = `6V-a_8;[
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detachedCriteria.getExecutableCriteria(session); m7X&"0X
return criteria.list(); j:D@X=|
} QC.WR'.
}, true); ?Dro)fH1
} 5T,Doxo
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public int getCountByCriteria(final }B2H)dG^K
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DetachedCriteria detachedCriteria){ |K?fVL
Integer count = (Integer) `j*&F8}
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getHibernateTemplate().execute(new HibernateCallback(){ iMRb`
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publicObject doInHibernate K1>.%m
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(Session session)throws HibernateException { q+XL,E
Criteria criteria = Izq]nR
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detachedCriteria.getExecutableCriteria(session); %C=^
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return 0S@O]k)
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criteria.setProjection(Projections.rowCount g~_cYy
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()).uniqueResult(); f !t2a//
} ty]JUvR@
}, true); \Ku=a{Ne
return count.intValue(); ay6G1\0W
} CBx 1.xL
} H=]$9ZH!
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用户在web层构造查询条件detachedCriteria,和可选的 v'*
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )
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PaginationSupport的实例ps。 NGB%fJ
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ps.getItems()得到已分页好的结果集 N'R^S98x
ps.getIndexes()得到分页索引的数组 ~/1kCZB
ps.getTotalCount()得到总结果数 y [e$
ps.getStartIndex()当前分页索引 :~loy'
ps.getNextIndex()下一页索引 *v3/8enf
ps.getPreviousIndex()上一页索引 dT8m$}h9
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 jPYed@[+
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 fV*x2g7w
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一下代码重构了。 s]`&9{=E
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我把原本我的做法也提供出来供大家讨论吧: %j=dKd>
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首先,为了实现分页查询,我封装了一个Page类: p?X.I]=vRv
java代码: !%J;dOcU
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/ _v5B>
/*Created on 2005-4-14*/ !zLd,`
package org.flyware.util.page; CF9a~^+%
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/** 6NJ"ty9Bp
* @author Joa |$Dt6{h
* h8>7si
*/ u7G@VZ Ux5
publicclass Page { 'vj45b
[CBA Lj5
/** imply if the page has previous page */ yXS ~PG
privateboolean hasPrePage; k\|G%0Jw
<aa#OX
/** imply if the page has next page */ z=<T[Uy
privateboolean hasNextPage; a#FkoA~M
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/** the number of every page */ p%,:U8fOR
privateint everyPage; ElhTB
x*}j$n( Oa
/** the total page number */ {YWj`K
privateint totalPage; @/H1}pM~
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/** the number of current page */ 0z/tceW'F
privateint currentPage; is?`tre\P
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/** the begin index of the records by the current KL#F5\ E
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query */ C$oY,A,
privateint beginIndex; l_iucN
7^'TU=ss_
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/** The default constructor */ 1;3oGuHj8
public Page(){ %]nYv#K
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} ]B=B@UO@.
<(`dU&&%"}
/** construct the page by everyPage )5gcLD/zI
* @param everyPage |\@e
* */ ?{%P9I
public Page(int everyPage){ meu\jg
this.everyPage = everyPage; "RuJlp
} ][S<M24]Q
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/** The whole constructor */ "5%G[MB
public Page(boolean hasPrePage, boolean hasNextPage, ^ $Q',
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int everyPage, int totalPage, %d($\R-*O
int currentPage, int beginIndex){ pez*kU+9
this.hasPrePage = hasPrePage; >T;"bcb
this.hasNextPage = hasNextPage;
dKDtj:
this.everyPage = everyPage; -liVYI2s
this.totalPage = totalPage; EAxg>}'1j
this.currentPage = currentPage; -VD[iH
this.beginIndex = beginIndex; h'^7xDw
} 2/=CrK
)`F?{Sg
/** #Bj{
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* @return LdR}v%EH
* Returns the beginIndex. *ntq;]
*/ 4Cke(G
publicint getBeginIndex(){ 'cy35M
return beginIndex; -'BJhi\Y]~
} O7ceSz
[Av87!kJ!X
/** !vfjo[v
* @param beginIndex ySP1WK
* The beginIndex to set. uljd)kLy4O
*/ Gv>,Ad
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publicvoid setBeginIndex(int beginIndex){ Sd'
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this.beginIndex = beginIndex; iHr{
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} VF!?B>
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/** ZJsc ?*@
* @return 4pV.R5:
* Returns the currentPage. 0`"]mYH
*/ 6g8{;6x
publicint getCurrentPage(){ sn_]7d+Q
return currentPage; 5X\3y4
} ,Bp\ i
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/** Z}f$KWj
* @param currentPage X/lLM`
* The currentPage to set. 6AqHzeh
*/ [|d:QFx
publicvoid setCurrentPage(int currentPage){ wblEx/FqE^
this.currentPage = currentPage; "@W0Lk[
} D^=_408\
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/** +
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* @return c 6}d{B[
* Returns the everyPage. G5ebb6[+
*/ b=:AFs{
publicint getEveryPage(){ If\u^c
return everyPage; qW6a|s0}
} 9@./=5N~3
HC*=E.J
/** Kpz>si?CL
* @param everyPage )I 4d_]&
* The everyPage to set. Bt[`p\p@
*/ z!)_'A
publicvoid setEveryPage(int everyPage){ SWUHHl
this.everyPage = everyPage; wg^#S
} &fdH
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/** {CR~G2Z
* @return BZQ98"Fz*
* Returns the hasNextPage. ,G
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*/ cn v4!c0
publicboolean getHasNextPage(){ gHQ[D|zu
return hasNextPage; :1q+[T/ @
} A1{P"p!
-_
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/** bRJYw6oA<
* @param hasNextPage GbwcbfH
* The hasNextPage to set. SOE#@{IXBa
*/ a)MjX<y
publicvoid setHasNextPage(boolean hasNextPage){ )W:`Q&/G
this.hasNextPage = hasNextPage; YM
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} ?Vb=W)Es
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/** &1%W-&bc6
* @return 'j !!h4
* Returns the hasPrePage. :t?9$ dL
*/ -. L)-%wIV
publicboolean getHasPrePage(){ N$M#3Y;
return hasPrePage; Z%D*2wm4
} Z_}vjk~s
7e/Uc!&*
/** F}DdErd!f
* @param hasPrePage sVZb[|zSri
* The hasPrePage to set. "V&2g?
*/ !
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publicvoid setHasPrePage(boolean hasPrePage){ M-K<w(,X
this.hasPrePage = hasPrePage; 'C1=(PE%`
} =<_xUh.
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/** K0@2>nR
* @return Returns the totalPage. G`ZpFg0Y
* ve.iyr
*/ n }7DL8
publicint getTotalPage(){ V=VL@=
return totalPage; 8js5/G+
} 2"~!Pu^.j
<P3r+ 1|R
/** HLg/=VF7?
* @param totalPage 1Z'cL~9
* The totalPage to set. 9hHQWv7TgK
*/ !.zUY6
publicvoid setTotalPage(int totalPage){ -TU7GCb=
this.totalPage = totalPage; Nb>|9nu
O
} %:h)8e-;
w
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} gAhCNOp
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Kf76./
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#,[
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 3%/]y=rA
%.r{+m
个PageUtil,负责对Page对象进行构造: r) T^ Td1
java代码: <GF)5QB
<^UB@'lCm
9U>ID{
/*Created on 2005-4-14*/ LG [2u
package org.flyware.util.page; ;9q3FuR
YPDc
/
import org.apache.commons.logging.Log; )-Zpr1kD
import org.apache.commons.logging.LogFactory; 6TbDno/!'
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/** U#ueG
* @author Joa o{4ya jt
* 95_?F7}9
*/ ,ZJI]Q=!
publicclass PageUtil { COOazXtW
VCiJ]$`M
privatestaticfinal Log logger = LogFactory.getLog zid?yuP
#E2`KGCzW
(PageUtil.class); bS3qX{5
c,Zs.
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/** " 6~pTHT
* Use the origin page to create a new page U>(5J,G
* @param page 7OS\j>hb~
* @param totalRecords uTpKT7t
* @return 79~,KFct
*/ I}puN!
publicstatic Page createPage(Page page, int Xj&{M[k<
7$z")JB
totalRecords){ V,<,;d fR
return createPage(page.getEveryPage(), +e)So+.W
rwtSn?0z"
page.getCurrentPage(), totalRecords); /&$'v:VB
} U)zd~ug?m
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/** 7,!Mmu
* the basic page utils not including exception 9;&2LT7z
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handler ;8JJ#ED
* @param everyPage X8ev uN
* @param currentPage 82~UI'f \
* @param totalRecords vPR1
TMi>
* @return page MfJk`-%~
*/ Xf:CGR8_
publicstatic Page createPage(int everyPage, int mbsdiab#N
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currentPage, int totalRecords){ j$Vv'on
everyPage = getEveryPage(everyPage); {v+i!a'+
currentPage = getCurrentPage(currentPage); &s"&rFFO[
int beginIndex = getBeginIndex(everyPage, 3Ym5SrKK
w^ui%9
&6H
currentPage); K-)*S\<}
int totalPage = getTotalPage(everyPage, 5hB&]6n
~B:Lai4"
totalRecords); DvG. G+mo#
boolean hasNextPage = hasNextPage(currentPage, W2wDSP-
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totalPage); 022YuqL<v
boolean hasPrePage = hasPrePage(currentPage); gu/eC
GuV-[
returnnew Page(hasPrePage, hasNextPage, N(dn"`8
everyPage, totalPage, blid* @-
currentPage, 3LG}x/l
EX>> -D7L
beginIndex); rzDqfecOmW
} [{Fr{La`D'
$.QnM
privatestaticint getEveryPage(int everyPage){ H+F?)VX}oA
return everyPage == 0 ? 10 : everyPage; 1HN_
} BtBo%t&
"ltvD\
privatestaticint getCurrentPage(int currentPage){ l'&l!D&
return currentPage == 0 ? 1 : currentPage; 7\"-<z;kK
} >RHK6c
e[ i&2mM
privatestaticint getBeginIndex(int everyPage, int #"O9\X/B
~r]ZD)
currentPage){ )3.udx
return(currentPage - 1) * everyPage; +DF<o
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} `tVBV:4\
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privatestaticint getTotalPage(int everyPage, int MCurKT<pQ
1ScfX\F=
totalRecords){ BNyDEFd
int totalPage = 0; nv{ou[vQ
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if(totalRecords % everyPage == 0) u,PrEmy-
totalPage = totalRecords / everyPage; m,K\e
else RL~\/#
totalPage = totalRecords / everyPage + 1 ; #Jy+:|jJ
/_*:
return totalPage; |O+R%'z'<
} E5jK}1t4V
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privatestaticboolean hasPrePage(int currentPage){ Fy`VQ\%7t
return currentPage == 1 ? false : true; ).9-=P HlX
} ;)83tx
/
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privatestaticboolean hasNextPage(int currentPage, ~NpnRIt
n j;
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int totalPage){ n >xhT r<
return currentPage == totalPage || totalPage == V3yO_Iqa
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0 ? false : true; `*KS`
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} >6:slNM#
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} J0@m
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 CS50wY
S&_ZQLiQ$
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 _]j=[|q 9
cn<9!2a
做法如下: `WWf?g
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 4yQ4lU,r
W;~^3Hz6
的信息,和一个结果集List: %- %/3
java代码: @*is]d+Ya
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/*Created on 2005-6-13*/ d^ipf*aLC
package com.adt.bo; A
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import java.util.List; U=Z@Ipu5T
%04>R'mN
import org.flyware.util.page.Page; Y
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/** }mu8fm'
* @author Joa dam.D.o"
*/ U!3nn#!yE
publicclass Result { 6XFO@c}d
dMRwQejY{7
private Page page; CrS[FM= +W
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private List content; 8'^eH1d'
~+l%}4RZ
/** _[0Ugfz(
* The default constructor +8Peh9"
*/ 0AR4/5.
public Result(){ 5Tn4iyg;B
super(); !RiPr(m@y
} :".!6~:2
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/** ot_jG)
* The constructor using fields kZUuRB~om
* jG)>{D
* @param page _'2r=a#`
* @param content A<>W^ow
*/ o }Tv^>L
public Result(Page page, List content){ y,Dfqt
this.page = page; N#T MU
this.content = content; ~+CNED0z+
} 8f8+3
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/** {7(h%]
* @return Returns the content. H{yPi7 P
*/ hzKfYJcQ|
publicList getContent(){ (O?z6g
return content; 27u$VHwb
}
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/** pKr3(5~
* @return Returns the page. JXPn
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*/ @o;m!CYB
public Page getPage(){ >x!N[N@G
return page; (&njZdcb*
} ;GH(A=}/Y
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/** :^l*_v{
* @param content 2$T~(tem
* The content to set. WY*}|R2R
*/ =1\'xz}p?
public void setContent(List content){ ;=C^l
this.content = content; &<tji8Dj
} zQ)[re)
{K[+nX=#
/** 8d Ftp3(
* @param page 2{U4wTu
* The page to set.
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*/ ZQ~?
publicvoid setPage(Page page){ $1Xg[>1g5
this.page = page; b[*di{?-
} i>!f|<
} R^PQ`$W 'R
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Q FX|ZsmK
2. 编写业务逻辑接口,并实现它(UserManager, rbP.N
?YU%
vo0[Z,aH5
UserManagerImpl) ?d_<S0j-)
java代码: aP"i_!\.aa
9oGsrClH
sM?DNE^BvW
/*Created on 2005-7-15*/ Y61E|:fV!
package com.adt.service; F." L{g
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import net.sf.hibernate.HibernateException; D_, 2z
#m8Oy|Y9`
import org.flyware.util.page.Page; .(`u'G=
+A:}5{
import com.adt.bo.Result; ZnmBb_eX
r*tGT_/6
/** 2t(E+^~
* @author Joa j?.VJ^Ff/u
*/ c*ytUI*
publicinterface UserManager { >6rPDzW`Dx
HX<5i>]0\u
public Result listUser(Page page)throws nk-?$'i9q
?np`RA
HibernateException; cFH,fj
R0m}I5Frs
} WcqYpPv
>+$1 p_
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.@[+05Yw
qbT].,?!U
java代码: M
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c\RDa|B,
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/*Created on 2005-7-15*/ !{ )H
package com.adt.service.impl; M)|}Vn;!
b,{?+8
import java.util.List; VqYe0-^=P
cdEZ
Y
import net.sf.hibernate.HibernateException; q@^=im
e|{6^g<ru
import org.flyware.util.page.Page; Xw![}L>
import org.flyware.util.page.PageUtil; 7H./o Vl
hd^?svID
import com.adt.bo.Result; xkqt(ng(
import com.adt.dao.UserDAO; Z7%>O:@z
import com.adt.exception.ObjectNotFoundException; `aSz"4Wd
import com.adt.service.UserManager; Ag?@fuk$J
]54V9l:
/** `Th!bk
* @author Joa 98V9AOgk
*/ ~rKo5#D
publicclass UserManagerImpl implements UserManager { <k^h&1J#g
ob0clJX
private UserDAO userDAO; f PDnkr
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/** 3RGVH,
* @param userDAO The userDAO to set. Nf3Kz#!B
*/ cG^'Qm
publicvoid setUserDAO(UserDAO userDAO){ 0iHK1Pt}
this.userDAO = userDAO; dIK!xOStA
} RL>[t
1Z*-@%RX
/* (non-Javadoc) OcIJT1
* @see com.adt.service.UserManager#listUser `U?;9!|;6
`cf&4Hn
(org.flyware.util.page.Page) |\,e9U>
*/ Q6DE|qnV
public Result listUser(Page page)throws LM<OYRB(
l tQ:c
HibernateException, ObjectNotFoundException { %n{E/06f
int totalRecords = userDAO.getUserCount(); Z*kg= hs^
if(totalRecords == 0) .YLg^JfZ
throw new ObjectNotFoundException Jzfzy0$
&)`A4bf%
("userNotExist"); O </<
page = PageUtil.createPage(page, totalRecords); A$%%;O
List users = userDAO.getUserByPage(page); B_@>HZ\&
returnnew Result(page, users); 7gPkg63
} zvD$N-#`p
c\-I+lMBi
} N/^r9Nu
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{?#g*QF|^
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fr:RiOPn
Yuh t<:`
询,接下来编写UserDAO的代码: 5 {'%trDEy
3. UserDAO 和 UserDAOImpl: y37n~~%
java代码: +#n[55d
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i7Y96]
/*Created on 2005-7-15*/ MiS$Y
package com.adt.dao; C8aYg
4qiG>^h9
import java.util.List; &Du!*V4A
t;ggc{
import org.flyware.util.page.Page; VNA VdP
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import net.sf.hibernate.HibernateException; Rl$NiY?2
54tpR6%3p
/** X0p=jBye~>
* @author Joa <.RgMPi
*/ r;}kw(ukC
publicinterface UserDAO extends BaseDAO { &OWiA;e?f
FFP>Y*v(
publicList getUserByName(String name)throws ~`
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op[OB=
HibernateException; ?JtFiw
]cFqKs
publicint getUserCount()throws HibernateException; RqH"+/wR
Rs5G5W@"A
publicList getUserByPage(Page page)throws nj
#Ab
&!m;s_gi
HibernateException; 2hu;N
:DQHb"(
} (x#4BI}L9)
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n T\W|
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+9,"ne1'e
java代码: 0xZq?9a
mu|#(u
G#n27y nh
/*Created on 2005-7-15*/ Bd)Qz(>rw
package com.adt.dao.impl; ?%B%[u
ZZ?=^g
import java.util.List; e9"<.:&
d-39G*;1
import org.flyware.util.page.Page; \jZvP`.2
^!N _Nx/M
import net.sf.hibernate.HibernateException; 6z!?U:bT
import net.sf.hibernate.Query; Zwp*JH+G
V$<og
import com.adt.dao.UserDAO; C$
nT&06o
F8>Fp"
/** c,4UnEoCR
* @author Joa ?$
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*/ TfVB~"&