Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 0h$GI"dR
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 z41_oG7
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 =j0x.fSe
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 /.5;in
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分页支持类: 2=PBxDs;
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java代码: NCA{H^CL
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package com.javaeye.common.util; N$?cX(|7
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import java.util.List; M/V(5IoP(
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publicclass PaginationSupport { z*~YLT&
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publicfinalstaticint PAGESIZE = 30; NnxM3*
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privateint pageSize = PAGESIZE; V'Y{v
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privateList items; aI#4H+/
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privateint totalCount; go)p%}s
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privateint[] indexes = newint[0]; hQJWKAf,/
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privateint startIndex = 0; P#GD?FUc
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public PaginationSupport(List items, int |U[y_Y\a
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totalCount){ r
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setPageSize(PAGESIZE); d+z[\i
setTotalCount(totalCount); FyD.>ot7M
setItems(items); (0*v*kYdL+
setStartIndex(0); g jG2
} mp`PE=
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public PaginationSupport(List items, int <Mgf]v.QS
~] =?b)B
totalCount, int startIndex){ ||TtNH
setPageSize(PAGESIZE); [h}K$q
setTotalCount(totalCount); vW.%[]
setItems(items); Oo%!>!Lt,
setStartIndex(startIndex); 3
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} AfWl6a?T8:
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public PaginationSupport(List items, int :q2YBa
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totalCount, int pageSize, int startIndex){ }(i(Ar-
setPageSize(pageSize); ;?6>mh(`
setTotalCount(totalCount); H$!-f>Rxa
setItems(items); y{rn-?`{
setStartIndex(startIndex); C@dGWAG
} @vH2Vydu
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publicList getItems(){ ^/KfH&E
return items;
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} . A<sr
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publicvoid setItems(List items){ LZWS^77
this.items = items; |Mg }2!/L
} 6zYaA
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publicint getPageSize(){ D?u`
return pageSize; .K9l*-e[=
} cqQRU
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publicvoid setPageSize(int pageSize){ GEE
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this.pageSize = pageSize; NXgRNca
} }z'DWp=uN
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publicint getTotalCount(){ CM 9P"-
return totalCount; i>Iee^_(
} 7Jx%JgF
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publicvoid setTotalCount(int totalCount){ .)ST[G]WK
if(totalCount > 0){ O<`R~
this.totalCount = totalCount; &telCg:
int count = totalCount / Dr'sIH^
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pageSize; ('WY5Yps
if(totalCount % pageSize > 0) D9^7m
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count++; oeNzHp_
indexes = newint[count]; #\b ;2>
for(int i = 0; i < count; i++){ agY5Dg7
indexes = pageSize * [-VGArD[k,
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i; gB+
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} ``-k{C#F
}else{ ^g]xU1] *
this.totalCount = 0; =x4a~=HX
} 9--dRTG
} *]!l%Uf%
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publicint[] getIndexes(){ S8*> kM'
return indexes; [2H[5<tH
} ,Oi^ySn
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publicvoid setIndexes(int[] indexes){ 5+FLSk
this.indexes = indexes; oWD)+5.]
} jM\ %$_/
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publicint getStartIndex(){ @KJV1t`
return startIndex; YKq0f=Ij
} L1MrrC
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publicvoid setStartIndex(int startIndex){ ;Vo mFp L
if(totalCount <= 0) =, TS MV
this.startIndex = 0; U?EG6t
elseif(startIndex >= totalCount) b Fn(w:1Q
this.startIndex = indexes PSEWL6=]N
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[indexes.length - 1]; N?^_=KE@
elseif(startIndex < 0) .D3`'K3t{[
this.startIndex = 0; ^N{X "
else{ ++k J\N{
this.startIndex = indexes ]-EN/V
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[startIndex / pageSize]; \4@a
} 'RQiLUF
} Loc8eToZ
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publicint getNextIndex(){ u7 u~
int nextIndex = getStartIndex() + p|s2G~0<
LT&/0
pageSize; JilKZQmk
if(nextIndex >= totalCount) P,`=]Y*
return getStartIndex(); hG~ Uz
else +WdL
return nextIndex; (-'PD_|
} /xf.\Z7<
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publicint getPreviousIndex(){ 85Dm8~
int previousIndex = getStartIndex() - D{3fhPNU<b
P|v ?
pageSize; %\l0-RA@<
if(previousIndex < 0) &&*wmnWCS{
return0; iW-t}}Z>B
else Y)v%
return previousIndex; Hq-v@@0 *
} th90O|;
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} YZ{;%&rB
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抽象业务类 S}O5l}E
java代码: 0O^U{#*$I
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/** ^:U;rHY
* Created on 2005-7-12 ,`+Bs&S 8
*/ $ JuLAqq
package com.javaeye.common.business; }R\B.2#M_@
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import java.io.Serializable; #e*$2+`[A
import java.util.List; {YfYIt=.
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import org.hibernate.Criteria; 5%#i79z&B
import org.hibernate.HibernateException; -/1d&
import org.hibernate.Session; l2r>|CGQ[
import org.hibernate.criterion.DetachedCriteria; vevx|<9,
import org.hibernate.criterion.Projections; ?SB5b ,
import np= J:v4
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org.springframework.orm.hibernate3.HibernateCallback; VJGwd`qo*A
import mxZ4
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J (=4
org.springframework.orm.hibernate3.support.HibernateDaoS ayN*fiV]
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upport; Aw5K3@Ltz
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import com.javaeye.common.util.PaginationSupport; nWd:>Ur
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public abstract class AbstractManager extends ;\1b{-' l
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HibernateDaoSupport { p~ mN2x ]
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privateboolean cacheQueries = false; -<_+-t
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privateString queryCacheRegion; Un~]Q?w
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publicvoid setCacheQueries(boolean \gjl^#;
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cacheQueries){ qNhH%tYQ
this.cacheQueries = cacheQueries; D~XU`;~u
} 7Z9.z4\
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publicvoid setQueryCacheRegion(String {P,>Q4N
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queryCacheRegion){ 8U8P
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this.queryCacheRegion = JB641nv
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queryCacheRegion; iz,]%<_PE
} l A 0-?k
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publicvoid save(finalObject entity){ |)~Ex 9%ev
getHibernateTemplate().save(entity); wbn^R'
} 7cy+Nz
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publicvoid persist(finalObject entity){ j'#)~>b
getHibernateTemplate().save(entity); ?L`MFR
} I=Gr^\x=
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publicvoid update(finalObject entity){ \z&03@Sw
getHibernateTemplate().update(entity); J{aQ1)
} tvGg@Xs\
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publicvoid delete(finalObject entity){ `8.1&fBr
getHibernateTemplate().delete(entity); IY-(-
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} XL{{7%j
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publicObject load(finalClass entity, y^5T/M
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finalSerializable id){ 7uWJ6Wk
return getHibernateTemplate().load
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(entity, id); #i'C
} nNkyOaK*4
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publicObject get(finalClass entity, @&/s~3
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finalSerializable id){ cg>!<T*
return getHibernateTemplate().get k8!hvJ)?
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(entity, id); ZJiuj!
} 0[_O+u
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publicList findAll(finalClass entity){ ahK?]:&QO
return getHibernateTemplate().find("from ,+swH;=7#r
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" + entity.getName()); {o Q(<&Aw
} Yg\{S<wr
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publicList findByNamedQuery(finalString a/wUeW
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namedQuery){ ~N)( ^ 4
return getHibernateTemplate (MF+/fi
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().findByNamedQuery(namedQuery); 44<9zHK
} H5F\-&cq
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publicList findByNamedQuery(finalString query, ?uNTUU,
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finalObject parameter){ #`fi2K&]j
return getHibernateTemplate 0:7v/S!:
]j%*"V
().findByNamedQuery(query, parameter); Y^*Lh/:h
} A &X
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publicList findByNamedQuery(finalString query, duZ|mT8Q==
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finalObject[] parameters){ a+4`}:KA#
return getHibernateTemplate (9WL+S
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().findByNamedQuery(query, parameters); "u3fs2
} WcV\kemf
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publicList find(finalString query){ [RGC!}"mr
return getHibernateTemplate().find ,6y-.m7>
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(query); /r::68_KQP
} sK""
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publicList find(finalString query, finalObject i{1)=_$Vt`
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parameter){ [N0/"> c
return getHibernateTemplate().find k8Su/U
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(query, parameter); m M\!4Yi`7
} >uP{9kDm
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public PaginationSupport findPageByCriteria X-*KQ+?
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(final DetachedCriteria detachedCriteria){ mTrI""Jsu;
return findPageByCriteria .>AFf9P
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); x`j$9XN5
} Eb4< 26A
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public PaginationSupport findPageByCriteria gnKU\>2k
&kr_CP:;
(final DetachedCriteria detachedCriteria, finalint uJ)\P
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startIndex){ h^[ppc{Z
return findPageByCriteria <.?^LT
9:}RlL+cOk
(detachedCriteria, PaginationSupport.PAGESIZE, F|
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startIndex); ^G7n#
} ]`CKQ>
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public PaginationSupport findPageByCriteria eJVOVPg<,
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(final DetachedCriteria detachedCriteria, finalint b& _i/n(
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pageSize, VfE^g\Ia
finalint startIndex){ 7Dx .;
return(PaginationSupport) |RvpEy76
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getHibernateTemplate().execute(new HibernateCallback(){ Hjo:;s
publicObject doInHibernate RJ`/qXL
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(Session session)throws HibernateException { JJbM)B@-
Criteria criteria = Q%AS;(d
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detachedCriteria.getExecutableCriteria(session); 9^C!,A{u4
int totalCount = ^c[CyZ:a
=w;xaxjL
((Integer) criteria.setProjection(Projections.rowCount Rm[rQ}:
+gD)Yd
()).uniqueResult()).intValue(); .x-Z+Rs{g
criteria.setProjection q9a
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7
(null); ]>S$R&a
List items = _+R_ms
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criteria.setFirstResult(startIndex).setMaxResults x/jN&;"/
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(pageSize).list(); zvQ^f@lq2
PaginationSupport ps = Sj]T{3mi
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new PaginationSupport(items, totalCount, pageSize, m?kIa!GM=
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startIndex); Jz:W-o
return ps; Y"]e H{
} [y&h_w.
}, true); @gl%A&a
} MCWG*~f
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public List findAllByCriteria(final i5~ /+~
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DetachedCriteria detachedCriteria){ R^Eu}?<f
return(List) getHibernateTemplate +D{*L0$D"
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().execute(new HibernateCallback(){ 48"Y-TV
publicObject doInHibernate !\D]\|Bo
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(Session session)throws HibernateException { WY.\<$7
Criteria criteria = l.NkS
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detachedCriteria.getExecutableCriteria(session); qeO6}A"^|
return criteria.list(); %Cbc@=k
} uK&wS#uY
}, true); h+'eFAZ
} $xn%i\
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public int getCountByCriteria(final J/P@m_Yx
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DetachedCriteria detachedCriteria){ 1-Wnc'(OK
Integer count = (Integer) DGuUI}|)
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getHibernateTemplate().execute(new HibernateCallback(){ GzZ|T7fm
publicObject doInHibernate (Ss77~W7
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(Session session)throws HibernateException { f6_|dvY3
Criteria criteria = cwD*>[j
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detachedCriteria.getExecutableCriteria(session); /Geks/
return Qmc;s{-r;
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criteria.setProjection(Projections.rowCount `\u),$
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()).uniqueResult(); z1KC$~{O
} u{lDof>
}, true); /*p?UW<*4
return count.intValue(); 6Bq2?;5
} Qc
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} 8!fAv$g0
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用户在web层构造查询条件detachedCriteria,和可选的 ZtK%b+MBP
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 =`.5b:e
`q{'_\gVt(
PaginationSupport的实例ps。 >D^7v(&
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ps.getItems()得到已分页好的结果集 {4jSj0W
ps.getIndexes()得到分页索引的数组 {c
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ps.getTotalCount()得到总结果数 mM^8YL
ps.getStartIndex()当前分页索引 T+`GOFx
ps.getNextIndex()下一页索引 O}iKPY8K
ps.getPreviousIndex()上一页索引 {aa,#B]i
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 zSvHv s
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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 >U
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一下代码重构了。 ]X;*\-
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我把原本我的做法也提供出来供大家讨论吧: ump:dL5{
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首先,为了实现分页查询,我封装了一个Page类: f7AJSHe
java代码: yW,#&>]# |
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/*Created on 2005-4-14*/ P##( V!YR
package org.flyware.util.page; u2m{Yx|
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7
/** ,7nb;$]
* @author Joa *E q7r>[
* - OGy-"
*/ !F s)"?
publicclass Page { 91Sb=9
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/** imply if the page has previous page */ 0lq4
privateboolean hasPrePage; }@0.
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/** imply if the page has next page */ z{+; '9C
privateboolean hasNextPage; @9P9U`ZP
)s[S.`STz
/** the number of every page */ H4",r5qw:
privateint everyPage; _[Wrd?Z
6D]G*gwk[
/** the total page number */ /faP]J)
privateint totalPage; :v ~q
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/** the number of current page */ B9Tztg
privateint currentPage; \B+SzW
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/** the begin index of the records by the current exU=!3Ji
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query */ 8pt<)Rs}
privateint beginIndex; rSCX$ @@F
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/** The default constructor */ >V=@[B(0
public Page(){ tce8*:rNH
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} &jd<rs5}
}ZGpd9D
/** construct the page by everyPage &8L\FAY0%9
* @param everyPage TTak[e&j3
* */ 3Ya6yz
public Page(int everyPage){ RLX^'g+P
this.everyPage = everyPage; ;XuEMq,Di
} n,LKkOG
]KT,s].
/** The whole constructor */ [:'?}p
public Page(boolean hasPrePage, boolean hasNextPage, VQ}3r)ch
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int everyPage, int totalPage, OvG |=
int currentPage, int beginIndex){ wA&)y>n-
this.hasPrePage = hasPrePage; Y\S^DJy
this.hasNextPage = hasNextPage; _qNLy/AY
this.everyPage = everyPage; '0rwNEg
this.totalPage = totalPage; -{mq\GvGn
this.currentPage = currentPage; Oj\mkg
this.beginIndex = beginIndex; OEi9
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} Qj[O$L0 $
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/** J, >PLQAa
* @return }f*S 9V
* Returns the beginIndex. XmR5dLc8
*/ .?]_yX
publicint getBeginIndex(){ K0a
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return beginIndex; }-iOYSn
} kfECC&"
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/** JPKZU<:+V
* @param beginIndex M&-/&>n!
* The beginIndex to set. "A3xX&9-q
*/ l_EI7mJ
publicvoid setBeginIndex(int beginIndex){ A2S9h,t
this.beginIndex = beginIndex; S*:w\nXP~
}
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/** p8J"%Jq}
* @return 8"^TWzg}L
* Returns the currentPage. c17==S
*/ )uWNN"
publicint getCurrentPage(){ 3f8Z?[Bb@
return currentPage; ?!-im*~w
} #C}(7{Vt
7?#32B
Gr
/** 54%}JA][
* @param currentPage JFdzA
* The currentPage to set. [)u{ -
*/ :E*U*#h/
publicvoid setCurrentPage(int currentPage){ NWj@iyi<
this.currentPage = currentPage; C
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} Fowh3go
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/** P://Zi6>
* @return S45_-aE
* Returns the everyPage. ,BAF?}04=
*/ Z8UM0B=i
publicint getEveryPage(){ -C<aB750O)
return everyPage; r U5'hK
} t,nB`g?
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/** gvYs<,:
* @param everyPage B[50{;X
* The everyPage to set. uD3_'a
*/ d5hE!=
publicvoid setEveryPage(int everyPage){ s ~G{-)*
this.everyPage = everyPage; OK(d&
} 4y.[tk5
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/** Df^S77&c!
* @return P#PQ4uK \
* Returns the hasNextPage. ?Pc3*.
*/ p7er04/}\
publicboolean getHasNextPage(){ BZ9iy~
return hasNextPage; "dTXT
} ~yN,F pD
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/** :_ox8xS4
* @param hasNextPage Zlo,#q
* The hasNextPage to set. v(~m!8!TI
*/ *E'K{?-K
publicvoid setHasNextPage(boolean hasNextPage){ 9v0|lS!-
this.hasNextPage = hasNextPage; Nig-D>OS
} F)Lbr>H?I
sd%~pY}
/** 7/L7L5h<
* @return Xg,BK0O
* Returns the hasPrePage. ibyA~YUN/
*/ %\0 Y1!Hw
publicboolean getHasPrePage(){ KHtY
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return hasPrePage; AAcbY;
} |#6Lcz7[
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/** d9"4m>ymS
* @param hasPrePage $}fA;BP
* The hasPrePage to set. 2Fi*)\{
*/ ~l~g0J
publicvoid setHasPrePage(boolean hasPrePage){ ): 6d_g{2
this.hasPrePage = hasPrePage; %3j5Q
} )VC) }
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/** T^_9R;
* @return Returns the totalPage. D2bUSRrb
* .&y1gh!=
*/ X[<9+Q-&
publicint getTotalPage(){ at!?"u
return totalPage; :F&WlU$L
} )w-?|2-w5
CCV~nf
/** Rd)QVEk>SD
* @param totalPage }T,uw8?f!
* The totalPage to set. "L]_NST
*/ `Z-`-IL
publicvoid setTotalPage(int totalPage){ }^muAr
this.totalPage = totalPage; z{\.3G
} Fm"$W^H
8*wI^*Q
} e+wd>iiB
zu#o<6E{
D3PF(Wx
il~,y8WTU{
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 n>WS@b/o
XJ;/kR
个PageUtil,负责对Page对象进行构造: 00i9yC8@6
java代码: N2>JG]G
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/*Created on 2005-4-14*/ !_@%/I6
package org.flyware.util.page; D_Y;N3E/rS
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import org.apache.commons.logging.Log; 9\F^\h{
import org.apache.commons.logging.LogFactory; z( wXs&z;
{/ta1&xyG
/** '' 6
* @author Joa 4rm/+Zes
* cu-WY8n
*/ Ty=}A MMyE
publicclass PageUtil { kbY@Y,:w
[C$ 0HW
privatestaticfinal Log logger = LogFactory.getLog #_d%hr~d
@lwqkJ
(PageUtil.class); &+v&Dd&
+-hmITJv
/** Fr~xN!
* Use the origin page to create a new page e\<I:7%Rg
* @param page ~J|0G6H
* @param totalRecords V;"'!dVX
* @return nFqMS|EN
*/ 7u zN/LAF
publicstatic Page createPage(Page page, int xk/(|f{L
>L%%B-
totalRecords){ DxlX-
return createPage(page.getEveryPage(), {)mlXo(On
,O}zgf*H;
page.getCurrentPage(), totalRecords); b7-a0zaN
} )l=j,4nn
-8IiQRS
/** v,jU9D\
* the basic page utils not including exception J?&9ofj&
r$KDNa$/a
handler xInWcQ
* @param everyPage mWh:,[o
* @param currentPage oW6.c]Vo
* @param totalRecords @:63OLlrG
* @return page >2a~hW|,
*/ Sz
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publicstatic Page createPage(int everyPage, int _#+i;$cO-X
'Gk|&^
currentPage, int totalRecords){ W;=ZQ5Lw
everyPage = getEveryPage(everyPage); \21!NPXH2
currentPage = getCurrentPage(currentPage); bu]bfnYi9
int beginIndex = getBeginIndex(everyPage, 2h=RNU|
wNlp4Z'[
currentPage); fRiHs\+
int totalPage = getTotalPage(everyPage, 8L:0Wp
(f)QEho7
totalRecords); FQ5# v{
boolean hasNextPage = hasNextPage(currentPage, %]-tA,u
t?\osPL
totalPage); {S?.bT%&
boolean hasPrePage = hasPrePage(currentPage); W+QI
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returnnew Page(hasPrePage, hasNextPage, {0?76|
everyPage, totalPage, %:NI@59
currentPage, s
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0:XmReO+k
beginIndex); ,-):&V:jF
} u URf
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#F'
privatestaticint getEveryPage(int everyPage){ J? C"be=
return everyPage == 0 ? 10 : everyPage; K$4Ky&89
} =_5-z|<
Af;$}P
privatestaticint getCurrentPage(int currentPage){ ="V6z$N
return currentPage == 0 ? 1 : currentPage; LVSJK.B
} mz47lv1?
HxjhP(
privatestaticint getBeginIndex(int everyPage, int +U[A.^t
`W5f'RU
currentPage){ =vR>KE
return(currentPage - 1) * everyPage; kp[Jl0K5
} jN'zNOV~
='(:fHhhX
privatestaticint getTotalPage(int everyPage, int w0pH|$"/P
K#>B'>A\
totalRecords){ gD-<^Q-
int totalPage = 0; nk[ixVc
zJPzI{-w|
if(totalRecords % everyPage == 0) \QVL%,.%M
totalPage = totalRecords / everyPage; 8{AzB8xp
else 'Ag?#vB
totalPage = totalRecords / everyPage + 1 ; _o;alt
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return totalPage; j
sm{|'
} =oBV.BST u
4g|}]K1s
privatestaticboolean hasPrePage(int currentPage){ YtFtU;{
return currentPage == 1 ? false : true; %
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} JMXCyDy;
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privatestaticboolean hasNextPage(int currentPage, C&\#{m_1B
d;K,2
int totalPage){ kEi!q
return currentPage == totalPage || totalPage == 2QdqVwm
{<V{0
s%
0 ? false : true; [5H#ay
} m}rUc29cS,
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4h-tR
} {D$+~lO
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Bx)4BPaN
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zpJQ7hym
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。 Zv-#v
q.*k
J/L
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 _G@)Bj^*
[:Sl^ Z&6M
做法如下: -GH>12YP
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 rOX\rI%0+
dW6sA65<Y
的信息,和一个结果集List: 04o(05K
java代码: *4]}_ .rG#
I=0`xF|4K-
D/v?nW
/*Created on 2005-6-13*/ NSZ9M%7
package com.adt.bo; W;Ct[Y8m
$/K<hT_
import java.util.List; ? g}G#j
,VI2dNst\
import org.flyware.util.page.Page; 6YNd;,it>p
L\aG.\
/** J.$N<.
* @author Joa ,XU<2jv]
*/ H>X:#xOA_
publicclass Result { `fS$@{YI_
]@0C1r
private Page page; )1N~-VuT
Dr)B0]KG
private List content; |cs]98FEf
9!;/+P
/** @P@?KZ..v!
* The default constructor PKJ w%.-
*/ dSkM A
public Result(){ 8u6*;*o
super(); G0)}?5L1J
} ;0FfP
,N93 H3(
/** n&1q*
* The constructor using fields NYw>Z>TD8c
* g=n{G@ *N
* @param page ^M0
* @param content ]jjHIFX
*/ BlnR{Y
public Result(Page page, List content){ 1
8%+ Hy=
this.page = page; GCZx-zD~>
this.content = content; 9eBD)tnw
} >P@g].Q-
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/** |0OY>5
* @return Returns the content. |h%=a8
*/ H\RejGR
publicList getContent(){ Ym% XCl
return content; g-? @a
} @Z.BYC
42M_ %l_
/** T5|e\<l
* @return Returns the page. rny(8z%Ck-
*/ s5h}MXIXw
public Page getPage(){ MroN=%|t
return page; xIA] 5@;a
} 8wV`mdKN
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/** B`|f"+.
* @param content |P@N}P@
* The content to set. ,R.rxoO
*/ gu|=uW K
public void setContent(List content){ Wn2'uZ5If
this.content = content; H-\Ym}BGu
} !#d5hjoX
&+ "<ia(
/** 1J([*)
* @param page =WT&unw}
* The page to set. Qo32oT[DM
*/
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publicvoid setPage(Page page){ ,oykOda:|
this.page = page; |M`'
} gFqF&t
} #N"m[$;QR
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A3)"+`&PUl
x$;RfK2&p
,p{naT%R
2. 编写业务逻辑接口,并实现它(UserManager, Dj>eAO>
djH&)&q!
UserManagerImpl) wx^Det
java代码: hC[=e`j
]VL} eHZ
Z_[ P7P
/*Created on 2005-7-15*/ 4%2APvLW
package com.adt.service; 63'm
@oZ
9#TD1B/
import net.sf.hibernate.HibernateException; @R%*; )*F
tn#cVB3
import org.flyware.util.page.Page; fLnwA|n=
O}>@G
import com.adt.bo.Result; l^Ob60)2
793 15A
/** >TMd1?,
* @author Joa )$RV)
*/ d?&`ZVl
publicinterface UserManager { Q 9fK)j1$
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public Result listUser(Page page)throws dP?prT
K[kK8i+(
HibernateException; QEg[
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} eZEk$W%
fX]`vjM{
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"MU-&**
rRg,{:;A
java代码: D'<L6w`
U$mDAi$
hw,nA2w\
/*Created on 2005-7-15*/ Vm|KL3}NRv
package com.adt.service.impl; iLch3[p%
.<zKBv
import java.util.List; d\uN
=WjHf8v;
import net.sf.hibernate.HibernateException; cef[T(>
+N=HI1^54R
import org.flyware.util.page.Page; "]#Ij6ml
import org.flyware.util.page.PageUtil; t5%cpkgh4
("\{=XAQ
import com.adt.bo.Result; u"q56}Q?]
import com.adt.dao.UserDAO; vP x/&x
import com.adt.exception.ObjectNotFoundException; ~v%6*9
import com.adt.service.UserManager; 4^uSW&`;/
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/** KJRAW]?{
* @author Joa & ?x R
*/ Gsv<Rjj:
publicclass UserManagerImpl implements UserManager { GA[Ebzi
ydy TDn
private UserDAO userDAO; g]lEG>y1R
p;>A:i
/** u
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* @param userDAO The userDAO to set. &nP0T-T5y
*/ gE _+r
publicvoid setUserDAO(UserDAO userDAO){ Vx(*OQ
this.userDAO = userDAO; /1MmOB
} "aOs#4N
RqgN<&g?
/* (non-Javadoc) N2O *g`YC
* @see com.adt.service.UserManager#listUser r5DRF4,7
V_:`K$
(org.flyware.util.page.Page) HD^#"
*/ ?>Sv_0
public Result listUser(Page page)throws Ss+F
wkM1tKhy/
HibernateException, ObjectNotFoundException { /QY F|%7!
int totalRecords = userDAO.getUserCount(); iqvLu{
if(totalRecords == 0) S[1<Qrv]
throw new ObjectNotFoundException hE|P|0U,n
.Q%Hi7JMi
("userNotExist"); ,c4HicRJ#
page = PageUtil.createPage(page, totalRecords); ~f h
List users = userDAO.getUserByPage(page); 4p,:}h
returnnew Result(page, users); sFc \L9 4
} . :Skc
j:h}ka/!p
} sq!$+=1-X
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q7X#LY k
@khFk.LBD
x"{aO6M
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 SI=$s>1
=0pt-FQ
询,接下来编写UserDAO的代码: h+}BtKA
3. UserDAO 和 UserDAOImpl: /~Y\KOH|
java代码: r,Uk)xa/^
O;H6`JQ
j{%;n40$
/*Created on 2005-7-15*/ %rylmioW>
package com.adt.dao; ]xQv\u
_ocCt XI9
import java.util.List; x~V[}4E%>
6nZ]y&$G-k
import org.flyware.util.page.Page; Ipk;Nq
S MWXP
import net.sf.hibernate.HibernateException; KLyRb0V
5MVa;m
/** &"^F;z/
* @author Joa Ca|egQv
*/ E+aePo U
publicinterface UserDAO extends BaseDAO { S"cTi[9
m\56BP-AM
publicList getUserByName(String name)throws 5dePpF D5
~w?02FU
HibernateException; e$J>z {
C^L+R7
publicint getUserCount()throws HibernateException; M]s\F(*ib
pR61bl)
publicList getUserByPage(Page page)throws ;Z]Wj9iY
ij
?7MP
HibernateException; 'XK 'T\m
g&s.
0+
} N1$u@P{
,^:{!?v
=rA?,74
J8qFdNK
XwY,xg&o
java代码: jr=9.=jI8k
&DLWlMGq
N d].(_
/*Created on 2005-7-15*/ ubwM*P
package com.adt.dao.impl; jH<
#)R
GC')50T J
import java.util.List; 2 ? qC8eC
$aV62uNf
import org.flyware.util.page.Page; =Hg!@5]H
mtmC,jnD
import net.sf.hibernate.HibernateException; <tD,Uu{P
import net.sf.hibernate.Query; O] @E8<?^
j'D%eQI,V
import com.adt.dao.UserDAO; WXy8<?s
"`>6M&`U
/** 0P$1=oK
* @author Joa 8A#,*@V[
*/ i#'K7XM2
public class UserDAOImpl extends BaseDAOHibernateImpl MgeC-XQM
|Xt.[1
implements UserDAO { Tn&