Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 e8[*=&
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 MLR3A
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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 [A3hrSw
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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 auO^v;s
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。 /yI~(8bO
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分页支持类: >2wjV"W?
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java代码: |mKd5[$
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package com.javaeye.common.util; P8TiB
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import java.util.List; >i0FGmxH
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publicclass PaginationSupport { P_qxw-s
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publicfinalstaticint PAGESIZE = 30; NZD
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privateint pageSize = PAGESIZE; xF ,J[Aj
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privateList items; ];< [Cln%
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privateint totalCount; 51rM6
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}
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privateint[] indexes = newint[0]; H_$"]iQ
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privateint startIndex = 0; Bz24U wcZ
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public PaginationSupport(List items, int L$jRg
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totalCount){ pY:xxnE
setPageSize(PAGESIZE); bG5c~
setTotalCount(totalCount); .t["kaA
setItems(items); O4}cv
setStartIndex(0); Dm5UQe
} 6L*y$e"Qc
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public PaginationSupport(List items, int +\{!jB*g
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totalCount, int startIndex){ 8..itty
setPageSize(PAGESIZE); =g&0CFF <
setTotalCount(totalCount); i=SX_#b^
setItems(items); -nU_eDy
setStartIndex(startIndex); 1r8]EaI
} aEgzQono
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public PaginationSupport(List items, int D}_\oE/n
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totalCount, int pageSize, int startIndex){ ?49wq4L;a
setPageSize(pageSize); %i^%D
setTotalCount(totalCount); 9J1&g(?>-
setItems(items); EKDv3aFQZ#
setStartIndex(startIndex); I=b#tUBh8
} myXp]=Sb?
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publicList getItems(){ 4[5Z>2w
return items; !>! l=Z
} Y[pGaiN:
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publicvoid setItems(List items){ pM4 j=F
this.items = items; i1sc oxX3\
} O,DA{> *m
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publicint getPageSize(){ m@yaF:
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return pageSize; K J~f ~2;
} kiXa2Yn*(d
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publicvoid setPageSize(int pageSize){ 1ra}^H}
this.pageSize = pageSize; Ot/Y?=j~
} 7$w:~VZ
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publicint getTotalCount(){ 2Gx&ECa,
return totalCount; v_Jp9
} L1aN"KGMF
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publicvoid setTotalCount(int totalCount){ 2Ejs{KUj
if(totalCount > 0){ fXL$CgXG\x
this.totalCount = totalCount; 9@^/ON\O
int count = totalCount / wCkkfTO
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pageSize; id*UTY
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if(totalCount % pageSize > 0) S__ o#nf`%
count++; 'av
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indexes = newint[count]; ";xG[ne$Be
for(int i = 0; i < count; i++){ s=28.
indexes = pageSize * }-Zfljj
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} (?~F}u
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}else{ /TpM#hkq/2
this.totalCount = 0; _~6AUwM
} in%+)`'nH7
} @P)GDB7A
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publicint[] getIndexes(){ lZb1kq%9g
return indexes; .'SM|r$
} {U&Mo97rzX
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publicvoid setIndexes(int[] indexes){ N>@AsI
this.indexes = indexes; F-2HE><+
} Oa*/jZjr
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publicint getStartIndex(){ r$*k-c9Bf
return startIndex; F[Peil+|`
} fv)-o&Q#
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publicvoid setStartIndex(int startIndex){ _{-GR -
if(totalCount <= 0) T 0Y=gn
this.startIndex = 0; 6)Oe]{-
elseif(startIndex >= totalCount) ZLBfQ+pM)
this.startIndex = indexes \z<'6,b
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[indexes.length - 1]; @8Co5`CVl
elseif(startIndex < 0) >)!"XFbb
this.startIndex = 0; 9t;aJFI
else{ rMLCtGi
this.startIndex = indexes Kx#G_N@
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[startIndex / pageSize]; Is-Kz}4L
} UD"e:O_
} -6Cxz./#yS
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publicint getNextIndex(){ KLbP;:sr
int nextIndex = getStartIndex() + "i9$w\lm
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pageSize; 7CNEP2}:R
if(nextIndex >= totalCount) ]%G[<zD,1
return getStartIndex(); (}bP`[@rX!
else ]`+>{Sx 1
return nextIndex; a*=\-;HaZ
} dB< \X.
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publicint getPreviousIndex(){ zYF'XB]4
int previousIndex = getStartIndex() - &W }ooGg
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pageSize; G+}|gG8
if(previousIndex < 0) XnV|{X%]U
return0; G4ZeO:r
else KXYq|w
return previousIndex; \@gs8K#
} !)
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} `/0X].s#o
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抽象业务类 nwW`Q>+#U
java代码: 0
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/** qH"e:
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* Created on 2005-7-12 L
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*/ { 5h6nYu
package com.javaeye.common.business; %-H
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import java.io.Serializable; 9%iqequ
import java.util.List; L,Uqt,
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import org.hibernate.Criteria; u'LA%l-
import org.hibernate.HibernateException; Pp#!yMxBr
import org.hibernate.Session; CEZ*a 0}=
import org.hibernate.criterion.DetachedCriteria; aRg-
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import org.hibernate.criterion.Projections; aY8>#t?
import Y~bp:FkS
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org.springframework.orm.hibernate3.HibernateCallback; T3!l{vG
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import "l2_7ZXsPT
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org.springframework.orm.hibernate3.support.HibernateDaoS
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upport; yD5T'np<4
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import com.javaeye.common.util.PaginationSupport; W<k) '|
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public abstract class AbstractManager extends j{S\X'?
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HibernateDaoSupport { ,8EeSnI
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privateboolean cacheQueries = false; ka*VQXk*
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privateString queryCacheRegion; nA5v+d-<T
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publicvoid setCacheQueries(boolean E #8 `X
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cacheQueries){ a!xKS8-S==
this.cacheQueries = cacheQueries; # 1I<qK
} &+JV\
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publicvoid setQueryCacheRegion(String A0o6-M]'0
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queryCacheRegion){ S\s1}`pNm
this.queryCacheRegion = ]p@7[8}
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queryCacheRegion;
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} %GjF;dJ
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publicvoid save(finalObject entity){ `N
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getHibernateTemplate().save(entity); p*n$iroy_{
} V'\4sPt
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publicvoid persist(finalObject entity){ P[aB}<1f0
getHibernateTemplate().save(entity); Vad(PS0
} ~Og'IRf
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publicvoid update(finalObject entity){ :n{rVn}G
getHibernateTemplate().update(entity); @ U:WWTzf
} sw8Ic\vT
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publicvoid delete(finalObject entity){ __'Z0?.4#
getHibernateTemplate().delete(entity); F2OU[Z,-]
} *cq#>rN
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publicObject load(finalClass entity, FL"I PX;S
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finalSerializable id){ PBR+NHrZ
return getHibernateTemplate().load H Viu7kue`
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(entity, id); x(}@se
} E+UOuf*(
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publicObject get(finalClass entity, 6D_4o&N
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finalSerializable id){ OA&N WAm4
return getHibernateTemplate().get rXo,\zI;u^
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(entity, id); D?8t'3no
} 5/>G)&
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publicList findAll(finalClass entity){ 64o`7
return getHibernateTemplate().find("from ;(TBg-LEK
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" + entity.getName()); Et# }XVCJ
} 3eFD[c%mN
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publicList findByNamedQuery(finalString Jel%1'Dc^
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namedQuery){ ;{j:5+'
return getHibernateTemplate K\,&wU
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().findByNamedQuery(namedQuery); >2Z:=HT
} pJK puoiX
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publicList findByNamedQuery(finalString query, 0ot=BlMu
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finalObject parameter){ 6(<AuhFu
return getHibernateTemplate C
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().findByNamedQuery(query, parameter); /!d,f4n
} <),FI <~
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publicList findByNamedQuery(finalString query, fb&K.6"
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finalObject[] parameters){ OKxPf]~4E
return getHibernateTemplate ?Ju=L|
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().findByNamedQuery(query, parameters); v=iz*2+X
} (:vY:-\ bO
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publicList find(finalString query){ %fK"g2:
return getHibernateTemplate().find DyYl97+Z?
1!0BE8s"@
(query); >c;qIP)Z
} YmNBtGhT
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publicList find(finalString query, finalObject O9:vPbn
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parameter){ !N?|[n1
return getHibernateTemplate().find `b# w3 2
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(query, parameter); SI8mr`gJ
} hdfNXZ{A"
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public PaginationSupport findPageByCriteria @1^iWM j
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(final DetachedCriteria detachedCriteria){ d+ql@e ]
return findPageByCriteria /$/\$f$
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); D.)R8X
} ,hYUxh45
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public PaginationSupport findPageByCriteria b"/P
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(final DetachedCriteria detachedCriteria, finalint HVh+Zk
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startIndex){ zA\DI]:+
return findPageByCriteria %(,JBa:G
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(detachedCriteria, PaginationSupport.PAGESIZE, s{Ryh.IyI
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startIndex); 57%:0loW
} *-ZJF6
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public PaginationSupport findPageByCriteria 0waQw7
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(final DetachedCriteria detachedCriteria, finalint DLJu%5F
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pageSize, Vdh5s 292h
finalint startIndex){ &NB[:S=
return(PaginationSupport) ;_1D-Mf
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getHibernateTemplate().execute(new HibernateCallback(){ N=)N
publicObject doInHibernate y*2:(nI
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(Session session)throws HibernateException { (VU: &.
Criteria criteria = `~VV1
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detachedCriteria.getExecutableCriteria(session); YDz:;Sp\
int totalCount = sj0Hv d9
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((Integer) criteria.setProjection(Projections.rowCount G\ru%
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()).uniqueResult()).intValue(); dl;^sn0s
criteria.setProjection n;/yo~RR
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(null); wRi!eN?
List items = s{'r'`z.
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criteria.setFirstResult(startIndex).setMaxResults #92MI#|n9
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(pageSize).list(); xCiY
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PaginationSupport ps = |J?KHI
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new PaginationSupport(items, totalCount, pageSize, #L`@["
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startIndex);
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return ps; <t.yn\G-w
} m!tB;:6
}, true); Go=MG:`
} !J3g, p*
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public List findAllByCriteria(final QZYD;&iY&
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DetachedCriteria detachedCriteria){ .?@$Rd2@W
return(List) getHibernateTemplate l]uF!']f
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().execute(new HibernateCallback(){ &Plc
publicObject doInHibernate [y W0U:m
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(Session session)throws HibernateException { )8!""n~
Criteria criteria = !Hr~B.f7
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detachedCriteria.getExecutableCriteria(session); HX7"w
return criteria.list(); 69p>?zn
} OtBVfA:[
}, true); R]/3`X9!d>
} %8DU}}Rj
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public int getCountByCriteria(final T9}G:6
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DetachedCriteria detachedCriteria){ tux/@}I
Integer count = (Integer) 6:fe.0H9
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getHibernateTemplate().execute(new HibernateCallback(){ a{GPAzO+
publicObject doInHibernate >DP9S@W
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(Session session)throws HibernateException { .Wc<(pfa
Criteria criteria = AU OL?st
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detachedCriteria.getExecutableCriteria(session); RplLU7
return .!/DM-C
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criteria.setProjection(Projections.rowCount I~-W4{
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()).uniqueResult(); zgI!S6q
} 1I{vBeMj
}, true); |Rd?s0u
return count.intValue(); -r@fLkwg
} yT.h[yv"w
} RXxi7^ U
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用户在web层构造查询条件detachedCriteria,和可选的 :k*'MU}
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 LP-~;
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PaginationSupport的实例ps。 .!e):&(8
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ps.getItems()得到已分页好的结果集 a\pOgIp
ps.getIndexes()得到分页索引的数组 ;4>YPH
ps.getTotalCount()得到总结果数 I8TqK
ps.getStartIndex()当前分页索引 MKf|(6;~
ps.getNextIndex()下一页索引 #^4p(eZ[}
ps.getPreviousIndex()上一页索引 PV$)k>H-
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ' ^E7T'v%
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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 X'Q?Mh
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一下代码重构了。 Z}#'.y\ f
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我把原本我的做法也提供出来供大家讨论吧: .ZQD`SRrI
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首先,为了实现分页查询,我封装了一个Page类: Q6)Wh6Cm
java代码: N-Fs-uB
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/*Created on 2005-4-14*/ "jV:L
package org.flyware.util.page; <+Eu.K&
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/** E:vgG|??
* @author Joa H1>~,zc>E
* {*mf Is
*/ K)b@,/ 5
publicclass Page { K</EVt,U~
#NQpr
/** imply if the page has previous page */ ]8@s+N
privateboolean hasPrePage; qW+'#Jh@TV
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/** imply if the page has next page */ niC ;WK
privateboolean hasNextPage; I]Ev6>=;
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/** the number of every page */ ~&HP}Q$#f
privateint everyPage; ^/]w}C#:d
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/** the total page number */ }uP`=T!"8
privateint totalPage; " GRR,7A
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/** the number of current page */ bUvVt3cm
privateint currentPage; Z5/*iun
rebnV&-
/** the begin index of the records by the current e~oh%l^C72
*.%z
query */ +@] ,JlYf
privateint beginIndex; eJbZA&:
)XCG4-1
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/** The default constructor */ {g9*t}l4
public Page(){ 1.24ZX
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} zUuOX5-6x
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/** construct the page by everyPage 5 EhOvt8
* @param everyPage 3JYhF)G
* */ :1asY:)vNP
public Page(int everyPage){ VAW:h5j2@
this.everyPage = everyPage; r&%TKm^/
} f$>KTb({B
O06 2c)vIY
/** The whole constructor */ /U$5'BoS
public Page(boolean hasPrePage, boolean hasNextPage, ,3XlX(P
6v"WI@b4
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int everyPage, int totalPage, gn//]|#H+
int currentPage, int beginIndex){ A@uU*]TqJ8
this.hasPrePage = hasPrePage; l XpbAW
this.hasNextPage = hasNextPage; uB=DC'lkg
this.everyPage = everyPage; t=nZ1GZyM
this.totalPage = totalPage; 8k{KnH
this.currentPage = currentPage; Mi~x(W@}3
this.beginIndex = beginIndex; k3(q!~a:.}
} QmgO00{
lA{JpH_Y8s
/** h;Hg/jv
* @return [KQ#b
* Returns the beginIndex. MO^Q 8v
*/ X9
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publicint getBeginIndex(){ 3</W}]$)p
return beginIndex; M^ZEAZi
} p40;@gUug
*82+GY]
/** >:Y"DX-
* @param beginIndex Q~R% |Q{&
* The beginIndex to set. tm1#Lh0
*/ |)VNf.aJZ
publicvoid setBeginIndex(int beginIndex){ B>}B{qi|
this.beginIndex = beginIndex; z:^(#G{
} 8n/8uRIR
lVv'_9yg
/** YsO3( HS
* @return q nb#~=x^
* Returns the currentPage. .oS[ DTn5S
*/ ARUzEo
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publicint getCurrentPage(){ e0<Wed
return currentPage; u>ZH-nw O
} F MX^k
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/** |A.nP9 hW
* @param currentPage redMlHM
* The currentPage to set. Sx:JuK@
*/ `+h+X9
publicvoid setCurrentPage(int currentPage){ mxnu\@}(
this.currentPage = currentPage; d>gQgQ;g
} r>#4Sr
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/** 2BKiA[
;;
* @return HTLS$o;Q
* Returns the everyPage. 0"}=A,o(w
*/ c(b2f-0!4
publicint getEveryPage(){ XuoyB{U
return everyPage; 00B,1Q HP
} kQF3DR$,B
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/** g@'2 :'\
* @param everyPage DH7]TRCMZ)
* The everyPage to set. tmd{Gx}c
*/ :d6]rOpX
publicvoid setEveryPage(int everyPage){ EfB.K}b^
this.everyPage = everyPage; !hFzIp
} qZdA%
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/** :HM~!7e
* @return .6!cHL3ln
* Returns the hasNextPage. bt*
*/ o@ m7@$7
publicboolean getHasNextPage(){ \[G"/]J
return hasNextPage; ;qO3m-(d
} c|@OD3w2lM
X?YT>+g;
/** AJ>$`=
* @param hasNextPage ]VR79l
* The hasNextPage to set. #<y/m*Ota
*/
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publicvoid setHasNextPage(boolean hasNextPage){ [!C!R$AMa
this.hasNextPage = hasNextPage; p//mVH%
} 4p7j"d5
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/** DUSQh+C
* @return ;eJ|)*
* Returns the hasPrePage. &_q8F,I \<
*/ (}5};v
publicboolean getHasPrePage(){ mPF<2:)wv
return hasPrePage; 4B9D
} 194n
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/** z6Fl$FFP
* @param hasPrePage /2''EF';
* The hasPrePage to set. 1,Es'
*/ Ey.%:
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publicvoid setHasPrePage(boolean hasPrePage){ KjMwrMgC
this.hasPrePage = hasPrePage; l,9rd[
} Ng1bjq}E2
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/** @EURp
* @return Returns the totalPage. '0^lMQMg
* ly69:TR7I
*/ 'pyIMB?x
publicint getTotalPage(){ 6B]i}nFH{+
return totalPage; )gz]F_
} _R^ZXtypd
aeVd.`lxM
/** r:PYAb=g
* @param totalPage &1Y7Ne
* The totalPage to set. uJ=d!Kn
*/ WZn"I&Z
publicvoid setTotalPage(int totalPage){ KSJ+3_7]k
this.totalPage = totalPage;
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} z0x^HDAeC
^?_MIS`4N
} h@]{j_$u
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 vM-kk:n7f
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个PageUtil,负责对Page对象进行构造: S?zP;
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java代码: [0 rH/{
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/*Created on 2005-4-14*/ [?=DPE%
package org.flyware.util.page; XZQ-Ig18
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import org.apache.commons.logging.Log; &G[W$2`@
import org.apache.commons.logging.LogFactory; f'MRC
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/** A
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* @author Joa t\]kVo)
*
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*/ :#\jx
publicclass PageUtil { ]<ay_w;
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privatestaticfinal Log logger = LogFactory.getLog 6kMEm)YjT
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(PageUtil.class); dNCd-ep
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/** \),zDO+
* Use the origin page to create a new page V)4?y9xZv
* @param page \ KsKb0sM
* @param totalRecords eA3NyL
* @return l: kW|
*/ ?r*}1WsH
publicstatic Page createPage(Page page, int O>I%O^
=(~*8hJ
totalRecords){ a^^OI|?
return createPage(page.getEveryPage(), {u0sbb(
@\:@_}Z`_}
page.getCurrentPage(), totalRecords); PN=5ICT
} )iVuac]E++
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/** 6mIeV0Q'
* the basic page utils not including exception "r8N-
h/P
l^%52m@{
handler Bs|#7mA[
* @param everyPage
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* @param currentPage @$CPTv3e
* @param totalRecords 6(7dr?^eGT
* @return page ;mr*$Iu 7|
*/ r[^O 7
publicstatic Page createPage(int everyPage, int 8M,z#DF
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currentPage, int totalRecords){ a2]>R<M
everyPage = getEveryPage(everyPage); ILiOEwHS7F
currentPage = getCurrentPage(currentPage); >)Bv>HM
int beginIndex = getBeginIndex(everyPage, t?b@l<,s
<[T{q
|*
currentPage); $VP\Ac,!
int totalPage = getTotalPage(everyPage, /Z~$`!J
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totalRecords); #)i+'L8
boolean hasNextPage = hasNextPage(currentPage, '
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#s#BYbF
totalPage); *5 \'$;Rg
boolean hasPrePage = hasPrePage(currentPage); B/mfm 7
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returnnew Page(hasPrePage, hasNextPage, naA8RD5/
everyPage, totalPage, sO!m,pK(
currentPage, |9BX
~`{
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beginIndex); +bR|;b(v
} 1. <g C
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privatestaticint getEveryPage(int everyPage){ ;TK$?hrv*1
return everyPage == 0 ? 10 : everyPage; *(XGNp[0
} bPkz= ^-
pB]*cd B?
privatestaticint getCurrentPage(int currentPage){ 32y 9r z
return currentPage == 0 ? 1 : currentPage; Q ~n%c7
} 3hEbM'L
KdzV^6K<c
privatestaticint getBeginIndex(int everyPage, int >wFn|7\)s>
t!u>l
currentPage){ dB QCr{7
return(currentPage - 1) * everyPage; )c 79&S
} yMmUOIxk\
16nU`TN
privatestaticint getTotalPage(int everyPage, int D'^%Q_;u
b.8T<@a
totalRecords){ YY$Z-u(
int totalPage = 0; ,Ij/
^EC}
h2= wC.
if(totalRecords % everyPage == 0) [@3.dd
totalPage = totalRecords / everyPage; b`Jsu!?{
else W59 xe&l
totalPage = totalRecords / everyPage + 1 ; *o!#5c
,g3n/'rP%
return totalPage; !/!Fc'A
} E8wkqZN
L$"pk{'
privatestaticboolean hasPrePage(int currentPage){ Po.by~|
return currentPage == 1 ? false : true; e?
|4O<@
} !CY*SGO
ttt4h
privatestaticboolean hasNextPage(int currentPage, !9.\A:G
"5Z5x%3I
int totalPage){ vIZFI
return currentPage == totalPage || totalPage == lS!O(NzqE'
2^Z"4t4
0 ? false : true; `=Bv+
} u@`y/,PX
V@EyU/VJ
\JCpwNT{P
} H
=&K_
&IsPqO
~jz51[{v
~E vGNnTL
9Sa6v?sRor
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。 *D`$oK,U
6TXTJ]er
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 7&w[h4Lw
n;:C{5
做法如下: =rkW325O
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 g@>93j=cZU
myd:"u,}9
的信息,和一个结果集List: nyOmNvZf
java代码: PeLzZ'$D
(B?ZUXM,
N0ef5J
JM`
/*Created on 2005-6-13*/ +Z=y/wY
package com.adt.bo; f|3LeOyz
~0}d=d5g
import java.util.List; ^7t1'A8e<
*/|<5X;xIA
import org.flyware.util.page.Page; d7 :=axo,
'TA
!JB+
/** pTncx%!W5
* @author Joa kjOkPp
*/ lg{/5gQG
publicclass Result { !-&;t7R
>9yy91H
private Page page; [dqh-7
''q#zEf6
private List content; L!`PM.:9
!HP=Rgh
/** SO<9?uk.
* The default constructor hrXk 7}9
*/ o]GZq..
public Result(){ I\Cg-&e
super(); "{2niBx
} Lzcea+*uw
~]n=TEJ>
/** 1qm*#4x
* The constructor using fields 9;L8%T
(
* K<5 0>uG
* @param page r8[)C cv
* @param content :YLurng/]
*/ k[@/N+;")`
public Result(Page page, List content){ ~]'yUd1gSZ
this.page = page; #3A|Z=,5
this.content = content;
*D1vla8
} 1(e64w@
.SNg2.
/** \Xr*1DI<
* @return Returns the content. jx
?"`;a
*/ IlB*JJnl
publicList getContent(){ vkeZ!klYB
return content; o1-_BlZ
} #qK5i1<
\: B))y?}d
/** SDs#w
* @return Returns the page. nUisC5HW
*/ FJT0lC
public Page getPage(){ %'S[f
return page; >&^jKfY
} u*rHKZ9i
d"Zyc(Jk
/** c:
(nlYZ
* @param content #]Jg>
* The content to set. %8d]JQ
*/ dfZ`M^NU
public void setContent(List content){ s .+`"rK
this.content = content; vI,T1%llu
} oa`7ClzD
tZu1jBO_Q4
/** i)$<j!L
* @param page Wv~&Qh}
* The page to set. x@[6u
*/ k~,
k@mR
publicvoid setPage(Page page){ ,ne3uPRu7~
this.page = page; O%px>rdkY
} m1xR uj]
} 'ud[#@2
#Jr4LQ@A9
O{Z${TC[
Iv*u#]{t
wz BI<0]z
2. 编写业务逻辑接口,并实现它(UserManager, QGE0pWL-a
8# x7q>?
UserManagerImpl) oArJ%Y>
java代码: {kr14l*2
M5L /3qLh1
cmU>A721
/*Created on 2005-7-15*/ Z9Z\2t
package com.adt.service; MIb[}w=
<d >!%
import net.sf.hibernate.HibernateException; QX-n l~
ru4M=D
import org.flyware.util.page.Page; ;V?d;O4u
pbw{EzM
import com.adt.bo.Result; {-%8RSK=<
z%\&n0
/** ?/myG{E
* @author Joa %E"Z &_3{
*/ ;|:R*(2
publicinterface UserManager { *%E\mu,,c
c]/S<w<
public Result listUser(Page page)throws xErb11
;uzLa%JQ
HibernateException; (L(n%
8(L6I%k*
} 8;#yXlf
9[sOh<W
u(\O@5a
-Zp BYX5e_
!SIk9~rJ
java代码:
|.L_c"Bc
dlIYzO<
0?dr(
/*Created on 2005-7-15*/ ia_lP
package com.adt.service.impl; FYK`.>L28
W+5. lf=2>
import java.util.List; 2U(qyC
90K&oof?M
import net.sf.hibernate.HibernateException; UM<s#t`\3
OkfxX&n
import org.flyware.util.page.Page; ),|z4~
import org.flyware.util.page.PageUtil; (OA4H1DL^
q'TIN{\.{
import com.adt.bo.Result; &HtTh {
import com.adt.dao.UserDAO; o"_'cNAz
import com.adt.exception.ObjectNotFoundException; r4<aEj;l
import com.adt.service.UserManager; OmS8cSYGc
ncUS8z
/** GR4DxlX
* @author Joa ZY@ntV?
*/ P(/eVD#v
publicclass UserManagerImpl implements UserManager { J0oeCb
+-,iC6kK
private UserDAO userDAO; Vjw u:M
JbQY{z!
/** x*=1C,C
* @param userDAO The userDAO to set. * ^V?u
*/ 5;,h8vW
publicvoid setUserDAO(UserDAO userDAO){ ge<D}6GQ
this.userDAO = userDAO; S>S7\b'
} =O-irGms*
(z?j{J
/* (non-Javadoc) -4zV
yW
S<
* @see com.adt.service.UserManager#listUser L"n)fe$
6U.|0mG[
(org.flyware.util.page.Page) &/WE{W
*/ K1Uq`T J
public Result listUser(Page page)throws L(sT/
;{q*
HibernateException, ObjectNotFoundException { P.QF9%
int totalRecords = userDAO.getUserCount(); ~QDM
.5
if(totalRecords == 0) C+[)^2M{
throw new ObjectNotFoundException aB?usVoS
aT(_c/t.
("userNotExist"); #sDb611}#
page = PageUtil.createPage(page, totalRecords); qmt9J?$k
List users = userDAO.getUserByPage(page); y@<2`h
returnnew Result(page, users); VpSpj/\m)'
} w( _42)v]g
ZfK[o{9>
} ! ?/:p.
P^48]Kj7
7 )rL<+
_53~D=
??U/Qi180
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 \"Y,1in#
,&qC
R
sw
询,接下来编写UserDAO的代码: eZN"t~\rX
3. UserDAO 和 UserDAOImpl: "H<us?r{
java代码: k)|.<
;i'[c`
I.GoY[u_%
/*Created on 2005-7-15*/ x5mg<y2`Ng
package com.adt.dao; nw0#gDI|
/ of K7/
import java.util.List; -]H~D4ng
@NqwJ.%g
import org.flyware.util.page.Page; BP0:<vK{
W)/^*,
Q7
import net.sf.hibernate.HibernateException; "Y=`w,~~
T'@+MA) ~
/** >m..
* @author Joa $2?j2}M
*/ G{E`5KIvm
publicinterface UserDAO extends BaseDAO { P(TBFu
. R/y`:1:W
publicList getUserByName(String name)throws j)6p>6
yxo=eSOM
HibernateException; m<#12#D
5<R m{
publicint getUserCount()throws HibernateException; [!-gb+L
G0Qw&
mqF
publicList getUserByPage(Page page)throws Vm>E F~ r
>MYDwH
HibernateException; 9;?u%
~"CGur P
} }Mt1C~{(
7K:V<vX5
fzQR0
$R1I(sJ
,0q1Id
java代码: ]MosiMJF
h0@a"DqK
f$ xp74hw3
/*Created on 2005-7-15*/ d6YXITL)\>
package com.adt.dao.impl; 2_+>a"8Y
6AGZ)gX
import java.util.List; hN
&?x5aC>
Bhd)# P
import org.flyware.util.page.Page; JHt
U"
I}3F'}JV<
import net.sf.hibernate.HibernateException; g}xL7bTlI>
import net.sf.hibernate.Query; Oo}h:3?
pB8D
import com.adt.dao.UserDAO; Y}N\|*ye-
"4)N]Nj
/** "+-
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* @author Joa K+F"V W*?
*/ _!@:@e)yB{
public class UserDAOImpl extends BaseDAOHibernateImpl czuIs|_K*
[eDrjf3m
implements UserDAO { MMs~f*
MQ-u9=ys
/* (non-Javadoc) {;c'@U
* @see com.adt.dao.UserDAO#getUserByName N8{jvat
7GYf#} N
(java.lang.String) :^v Q4/,
*/ C,Nf|L((6
publicList getUserByName(String name)throws 1 _?8 OU
!m+Pd.4TaB
HibernateException { >|E]??v
String querySentence = "FROM user in class 5M0Q'"`F:
L(VFzPkY%
com.adt.po.User WHERE user.name=:name"; d8wVhZKI"
Query query = getSession().createQuery &aLTy&8Fv
D}98ZKi
(querySentence); 30!DraW8
query.setParameter("name", name); (WyNO QO'
return query.list(); e~N&?^M
} -AdDPWn
/I=|;FGq
/* (non-Javadoc)
X8$Mzeq
* @see com.adt.dao.UserDAO#getUserCount() 5@w6pda
*/ &*=!B9OBI
publicint getUserCount()throws HibernateException { U]=yCEb8p
int count = 0; z'EQdQ)
String querySentence = "SELECT count(*) FROM %N*[{j= ^
i[!|0U`p
user in class com.adt.po.User"; J rx^
Query query = getSession().createQuery )8@-
j Q5 F}
(querySentence); zjQ746<&)i
count = ((Integer)query.iterate().next 73;Y(uh9
Q[biy{(b8
()).intValue(); x#D%3v"l_*
return count; p"ZvA^d\
} nF <K84
uL`#@nI
/* (non-Javadoc) SIJ7Y{\.
* @see com.adt.dao.UserDAO#getUserByPage d_yvG.#C
aDF@AS
(org.flyware.util.page.Page) P}v
;d]
*/ u2 s
publicList getUserByPage(Page page)throws ,t9EL 21
@N4_){s*
HibernateException { ws'e
String querySentence = "FROM user in class .Vbd-jr'M
n1."Qix0
com.adt.po.User"; *[Z`0AgP
Query query = getSession().createQuery @7twe;07r
-tj#BEC[H(
(querySentence); k$3pmy*
query.setFirstResult(page.getBeginIndex()) JU?;Kq9R
.setMaxResults(page.getEveryPage()); .9nqJ7]
return query.list(); yE8D^M|g
} !kovrvM6F
.xJ54Vz
} K%v:giN$l`
D$hQ-K
4=L >
L|CdTRgRCB
TEz;:* ,CG
至此,一个完整的分页程序完成。前台的只需要调用 atTR6%!6
41X`.
userManager.listUser(page)即可得到一个Page对象和结果集对象 E>bkEm
LZV- E=`
的综合体,而传入的参数page对象则可以由前台传入,如果用 r1L@p[>
XIInI
webwork,甚至可以直接在配置文件中指定。 7;EDU
@]l|-xGCWn
下面给出一个webwork调用示例: * ,aF-
java代码: 0=$/
q<&1,^A
hIe .Mv-I)
/*Created on 2005-6-17*/ .-Lrrk)R+
package com.adt.action.user; >v+1v
a
!VWWUTm?
import java.util.List; 0/R;g~q@
f .O^R~,
import org.apache.commons.logging.Log; Kb%Y%j
import org.apache.commons.logging.LogFactory; =XR~I
import org.flyware.util.page.Page; MB)<@.A0
LYDiqOrx
import com.adt.bo.Result; 4 Ej->T.
import com.adt.service.UserService; TKB8%/_p
import com.opensymphony.xwork.Action; n
_K1%
d{S'6*`D
/** c4fH/-
* @author Joa cp`Jep<T
*/ #X-C~*|>j
publicclass ListUser implementsAction{ dn
6]qW5
g *Js4
privatestaticfinal Log logger = LogFactory.getLog Cbff:IP
oco,sxT
(ListUser.class); z!g$#hmL>
t"VT['8
private UserService userService; hEZvi
*K/K97
private Page page; 5iA>Z!sP[
50_[hC&C)
privateList users; wH~A>
4*(
<m-(B"FX
/* L$PbC!1
* (non-Javadoc) `+,?%W)
* L`nW&;w'
* @see com.opensymphony.xwork.Action#execute() 5A0]+)5E8
*/ j\ y!
publicString execute()throwsException{ t%qep|
Result result = userService.listUser(page); =yod
page = result.getPage(); ^Q8yb*MN
users = result.getContent(); UR'[?
return SUCCESS; s<YN*~
} Lf9hOMHx
Ey=2zo^F
/** f;'*((
* @return Returns the page. *u+DAg'&
*/ |Hf|N$
public Page getPage(){ 4/(#masIL
return page; eo]nkyYDP
} A%D'Z85
-
!aT:0m$:9c
/** @aS)=|Ls\
* @return Returns the users. 9lq5\ tL-
*/ edL2ax
publicList getUsers(){ Ze0qRLuH!
return users; v2x+_K}J
} }b1G21Dc!
!>9s
/** %+'Ex]B
* @param page { "]!zL
* The page to set. 2^'Ec:|f
*/ ys`-QlkB
publicvoid setPage(Page page){ fG0ZVV!
this.page = page; #L.,aTA<
} sa.H,<;
VP1hocW
/** F6U#EvL
* @param users ]
2
`%i5
* The users to set. 'Ix@<$~i3F
*/ KYiJXE[Q-
publicvoid setUsers(List users){ EDnNS
this.users = users; z6`0Uv~
} -E}X`?WhD
/b=C
/** ;^N
lq3N
* @param userService `4K|L6
* The userService to set. _$UJ'W})/
*/ _<AkM"
publicvoid setUserService(UserService userService){ b+~_/;Y9
this.userService = userService; Z^'~iU-?
} v]SxZLa
} )WoH>D
Z#.d7B"
*EuX7LEu_
l,o'J%<%
1m5l((d
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Ey7zb#/<!
Mxl;Im]!`.
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 :)lS9<Y}
]T)N{"&N/
么只需要: HO<|EH~lu
java代码: I(M/X/
336ETrG^0
T`e`nQ0nn
<?xml version="1.0"?> 9n(68|^$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork v?."`,e
?>;b,^4
1.0//EN" "http://www.opensymphony.com/xwork/xwork- gGP6"|tc4
ChK-L6
1.0.dtd"> (xo`*Q,+
LAC&W;pJ"
<xwork> !yv>e7g^
cAN!5?D\
<package name="user" extends="webwork- :E-$:\V0}k
,P9F*;Dj
interceptors"> lrJV"H
Pm%xX~H
<!-- The default interceptor stack name /0\g!29l<
~u%$ 9IhM
--> NFTv4$5d
<default-interceptor-ref rXW.F'=K6
4w+AOWjd
name="myDefaultWebStack"/> S
TWH2_`
kl]V_ 7[
<action name="listUser" ,ciX *F"
?t%{2a<X
class="com.adt.action.user.ListUser"> s~{rC{9X
<param {^1O
{m*lt3$k
name="page.everyPage">10</param> bD{tsxm[9
<result q0}u%Yz
4~Qnhv7
name="success">/user/user_list.jsp</result> z I2DQ]
9
</action> R3G\Gchd
f"Iui
</package> 2|j=^
t]SB.ja
</xwork> -+[Lc_oNPx
|?V7E\S
W(]A^C=/
LM eI[Ji
^mLX}E]
rCF=m]1zxT
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 g)6>=Qo`8E
fNLO%\G~2
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 (nQm9 M(
poAJl;T
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 (d#&m+
g]
ry|a_3X(I
E#_/#J]UQn
no8\Oees
^# #j
{h7
我写的一个用于分页的类,用了泛型了,hoho $9?:P}$v
CF>&mXg\
java代码: *sldv
,Vq$>T@z
vu)EB!%[
package com.intokr.util; oz=V|7,
)Lz
=[e
import java.util.List; xS UpVK
A5j?Yts
/** J&j5@
* 用于分页的类<br> by+xK~>
* 可以用于传递查询的结果也可以用于传送查询的参数<br> LilK6K
* H<|}pZ
* @version 0.01 (-$5YKm
* @author cheng bVz<8b6h'-
*/ +c/!R|h=S
public class Paginator<E> { LBq2({="
privateint count = 0; // 总记录数 ftpPrtaP
privateint p = 1; // 页编号 a+HK
fK
privateint num = 20; // 每页的记录数 O#k; O*s'
privateList<E> results = null; // 结果 |= cc >]
X'b3CS4
/** q6pHL
* 结果总数 8KJ`+"<=@
*/ ' ds2\gN
publicint getCount(){ .u\$wJ9Ai
return count; (.=ig
X
} 7>z {2D
J;~YD$
publicvoid setCount(int count){ ]*P9=!x|M
this.count = count; Pl=)eq YY
} 1Du5Z9AM
"Bwz
Fh
/** E{[Y8U1n
* 本结果所在的页码,从1开始 &Z>??|f
* \)5mO 8w
* @return Returns the pageNo. <pV8
+V)
*/ zgz!"knVx
publicint getP(){ j_d}?jh
return p; p>eYi \'
} 9{4oz<U
8x-19#
/** / fUdb=!Z
* if(p<=0) p=1 3|!3R'g/ >
* EC5= 2w<
* @param p XY{N"S8
*/ e|:\Ps `8
publicvoid setP(int p){ ]d[e
if(p <= 0) lusUmFm'*
p = 1; Pk;/4jt4
this.p = p; $}vzBuWHwN
} j^#p#`m
md<^x(h"<
/** _IdW5G
* 每页记录数量 `uMc.:5\
*/ Q9AvNj>X
publicint getNum(){
ilQ}{p6I
return num; g%Tokl
} S`YT"|~
;6 W[%{
/** Csy$1;"A
* if(num<1) num=1 HI{q#
*/ F?tWx+N<{
publicvoid setNum(int num){ b-/QZvg
if(num < 1) @5wc 3y
num = 1; dhA~Yu
this.num = num; 2]?=\_T
} LZ_0=Xx%
)#z{P[X^
/** 7b08Lo7b
* 获得总页数 \"$P :Uv
*/ K"VcPDK
publicint getPageNum(){ C_>XtcU
return(count - 1) / num + 1; N@tKgx
} ~tWh6-:|{J
c_ncx|dUs
/** xDU\mfeGj
* 获得本页的开始编号,为 (p-1)*num+1 ?7V~>i8[
*/ 9#7W+9
publicint getStart(){ hFm^Fy[R
return(p - 1) * num + 1; ~C^:SND7
} #<==7X#
\,Ws=9f
/** O$r/{{I.
* @return Returns the results. n=4
*/ sQA_ 6]`
publicList<E> getResults(){ ;8XRs?xyd
return results; z H-a%$5
} 'WhJ}Uo\
$365VTh"
public void setResults(List<E> results){ :8eI_X
this.results = results; ?R)dxuj
} #S9J9k
{|>Wwa2e
public String toString(){ [m{sl(Q
StringBuilder buff = new StringBuilder %m dtVQ@
J;Z2<x/H
(); O<Q8%Az
buff.append("{"); &kzysv-_
buff.append("count:").append(count); 66F?exr
buff.append(",p:").append(p); 5b/ ~]v
buff.append(",nump:").append(num); -t S\
buff.append(",results:").append :,JjN&
BVeMV4
(results); 4 @{?4k-cq
buff.append("}"); _b%)
return buff.toString(); W;=Ae~
} /;(ji?wN
Ur]$@N
} #0T/^ #
oDu6W9 +
%H\J@{f