Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 `I#`:hj
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ,5.
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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 ,Z5Fea
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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 yzg9I
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分页支持类: {G%3*=?,j
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java代码: $P;UoqG<&
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package com.javaeye.common.util; C5;wf3
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import java.util.List; hLo>R'@uN
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publicclass PaginationSupport { qy&\Xgn;GA
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publicfinalstaticint PAGESIZE = 30; P9s_2KOF
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privateint pageSize = PAGESIZE; 8$m1eQ`{
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privateList items; rei5{PC
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privateint totalCount; Ih3$
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privateint[] indexes = newint[0]; dE GX3 -
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privateint startIndex = 0; wonYm27f
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public PaginationSupport(List items, int IX.sy
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totalCount){ j-6v2MH
setPageSize(PAGESIZE); 82s5VQ6
setTotalCount(totalCount);
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setItems(items); L20rv:W$h
setStartIndex(0); -$9~xX
} yfC2^#9 Zu
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public PaginationSupport(List items, int @Kp1k> ov
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totalCount, int startIndex){ |
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setPageSize(PAGESIZE); phmVkV2a;#
setTotalCount(totalCount); P#v^"}.Wd
setItems(items); "f<#.}8
setStartIndex(startIndex); =1IEpxh%
} ?yf_Dt
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public PaginationSupport(List items, int {KsVK4\r
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totalCount, int pageSize, int startIndex){ Yw1Y-M
setPageSize(pageSize); @7 -D7
setTotalCount(totalCount);
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setItems(items); ?Nu#]u-
setStartIndex(startIndex); NZfd_? 3
} 'QR4~`6I
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publicList getItems(){ =EWD
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return items; /cYk+c
} F@EZ;[
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publicvoid setItems(List items){ G>JxIrN0
this.items = items; J+iX,X
} z1FL8=
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publicint getPageSize(){ nSS}%&a:LX
return pageSize; GRy4cb2
} O'fc/cvh='
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publicvoid setPageSize(int pageSize){ soDfi-2o3
this.pageSize = pageSize; %xHu,*
} 8TI#7
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publicint getTotalCount(){ %uW<
return totalCount;
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} )Yrr%f`\
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publicvoid setTotalCount(int totalCount){ }FZp840
if(totalCount > 0){ g&P9UW>qS
this.totalCount = totalCount; -: C[P
int count = totalCount / [RW,{A
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pageSize; a0 qj[+
if(totalCount % pageSize > 0) /CbkqNV
count++; r&=r/k2
indexes = newint[count]; WFXx70n
for(int i = 0; i < count; i++){ ${e -ffyy
indexes = pageSize * ijg,'a~3E
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} x7Eeb!s0f,
}else{ noFh p
this.totalCount = 0; WVj&0
} J09ZK8
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} *x5o=)Y
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publicint[] getIndexes(){ N!Rt;Xm2@
return indexes; wAPO{3
} eMztjN
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publicvoid setIndexes(int[] indexes){ N0=b[%g;n
this.indexes = indexes; K:C+/O
} 7~:>WMv9
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publicint getStartIndex(){ Gtf1}UJC
return startIndex; oA[2)BU
} - f+CyhR"*
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publicvoid setStartIndex(int startIndex){ uLF\K+cz
if(totalCount <= 0) 3$;J0{&[i
this.startIndex = 0; N
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elseif(startIndex >= totalCount) Ogn,1nm%
this.startIndex = indexes 9
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[indexes.length - 1]; 3KbUHSx
elseif(startIndex < 0) ^BQ>vI'.4
this.startIndex = 0; >Y44{D\`
else{ bXk:~LE
this.startIndex = indexes Z5 w`-#
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[startIndex / pageSize]; qEPf-O:lm
} A5`#Ot*3
} u)wu=z8
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publicint getNextIndex(){ 1i ?gvzrq
int nextIndex = getStartIndex() + i_'|:Uy*F
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pageSize; s#M?
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if(nextIndex >= totalCount) uHTKo(NG
return getStartIndex(); ikeJDKSG
else @?(nwj~ s`
return nextIndex; K%o6hBlk_
} T
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@DRfNJ}
publicint getPreviousIndex(){ )WzGy~p8K
int previousIndex = getStartIndex() - 3XM Bu*
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pageSize; `@W3sW/^
if(previousIndex < 0) }S1Z>ZA5
return0; zS#f%{
else Tq_1wX'\
return previousIndex; H!Fr("6}
} $@XPL~4
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} bf&.rJ0
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抽象业务类 fq)Ohb
java代码: mg/C Ux
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/** `HMligT
* Created on 2005-7-12 Te{aB"B
*/ ^R&_}bp
package com.javaeye.common.business; ~GsH8yA_P
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import java.io.Serializable; {m1t~ S
import java.util.List; 'M]CZ}
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import org.hibernate.Criteria; ^Y1AeJ$L
import org.hibernate.HibernateException; eP-R""uPw
import org.hibernate.Session; o+PQ;Dl
import org.hibernate.criterion.DetachedCriteria; HY@kw>I
import org.hibernate.criterion.Projections; N>uZ t2
import ^H@!)+
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org.springframework.orm.hibernate3.HibernateCallback; 0%(4G83gw
import P"[ifsp
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org.springframework.orm.hibernate3.support.HibernateDaoS VyBJIzs0
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upport; y&KoL\
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import com.javaeye.common.util.PaginationSupport; $Sc08ro
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public abstract class AbstractManager extends #]N&6ngJ
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HibernateDaoSupport { -Ihn<<uE?
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privateboolean cacheQueries = false; Ynk><0g6
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privateString queryCacheRegion; ?trt4Tbe/
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publicvoid setCacheQueries(boolean 4q@9
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cacheQueries){ pU'`9fLi_
this.cacheQueries = cacheQueries; ZipK;!9by
} VLwJ6?.f'
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publicvoid setQueryCacheRegion(String .yHHogbt
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queryCacheRegion){ pE YrmC
this.queryCacheRegion = lL(}dbT~N
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queryCacheRegion; R+@sHsZ@
} qU
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publicvoid save(finalObject entity){ i &SBW0)
getHibernateTemplate().save(entity); JXZ:Wg
} Cx1Sh#9
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publicvoid persist(finalObject entity){ cE_Xo.:Y,
getHibernateTemplate().save(entity); :Z7"c`6L!~
} x"h)"Y[c5
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publicvoid update(finalObject entity){ I_Mqh4];
getHibernateTemplate().update(entity); 0
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} 6{FS/+
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publicvoid delete(finalObject entity){ ?6.KS
getHibernateTemplate().delete(entity); u0 'pR#
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} .-1{,o/&Q
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publicObject load(finalClass entity, L{o >D"
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finalSerializable id){ .ON$vn7
return getHibernateTemplate().load ;MdK3c
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(entity, id); Y;I(6`,Y
} %lqG* dRx0
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publicObject get(finalClass entity, }1^tK(Am
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finalSerializable id){ VHXR)}
return getHibernateTemplate().get $4ZDT]n
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(entity, id); N%M>,wT
} yI)RGOV
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publicList findAll(finalClass entity){ (^@;`8Dy8
return getHibernateTemplate().find("from uBL~AC3>O
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" + entity.getName()); :O@,Z_"
} X:} 5L>'
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publicList findByNamedQuery(finalString 5IF~]5s
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namedQuery){ W~@GK
return getHibernateTemplate
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().findByNamedQuery(namedQuery); G4`sRaT.
}
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publicList findByNamedQuery(finalString query, GT`<jzAi Q
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finalObject parameter){ HDXjH|of
return getHibernateTemplate TYLl_nGr
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().findByNamedQuery(query, parameter); snk{u/0Xm
} '/"M02a
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publicList findByNamedQuery(finalString query, tZ{q\+h
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finalObject[] parameters){ MH~qfH>K
return getHibernateTemplate `?S?)0B
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().findByNamedQuery(query, parameters); 5<GRi"7A@
} <?va)
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publicList find(finalString query){ !v;_@iW3e
return getHibernateTemplate().find +H^V},dBp!
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(query); 3b/vyZF
} DDCQ Af
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publicList find(finalString query, finalObject 8LM1oal}
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parameter){ kAF}*&Kzd~
return getHibernateTemplate().find )cmLo0`$
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(query, parameter); 1R~WY'Ed
} 25@j2K (
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public PaginationSupport findPageByCriteria ?kxWj(D
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(final DetachedCriteria detachedCriteria){ 50hh0!1
return findPageByCriteria JGNxJ S<]
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 5nIlG
} qO3BQ]UF
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public PaginationSupport findPageByCriteria 4 AmF^H
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(final DetachedCriteria detachedCriteria, finalint A-`J!xj#/
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startIndex){ ~acK$.#
return findPageByCriteria B91PlM.
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(detachedCriteria, PaginationSupport.PAGESIZE, |Ie`L("
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startIndex); &B,& *Lp
} bvRGTOxO
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public PaginationSupport findPageByCriteria YqCK#zT/
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(final DetachedCriteria detachedCriteria, finalint |(ju!&
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pageSize, +\$|L+@Z
finalint startIndex){ ,ST.pu8N.
return(PaginationSupport) M@@O50~
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getHibernateTemplate().execute(new HibernateCallback(){ _Vf|F
publicObject doInHibernate 'm? x2$u8
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(Session session)throws HibernateException { u`2k6.-
Criteria criteria = s3!LR2qiF
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detachedCriteria.getExecutableCriteria(session); ~"0X,APR5
int totalCount = _%%"Y}
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((Integer) criteria.setProjection(Projections.rowCount >^HTghgRD
w:+#,,rwzV
()).uniqueResult()).intValue(); Bzt`9lg
criteria.setProjection E}j8p_p
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(null); Y rnqi-P
List items = |^{" 2l"j
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criteria.setFirstResult(startIndex).setMaxResults O!Cu.9}
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(pageSize).list();
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PaginationSupport ps = ?^5*[H
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new PaginationSupport(items, totalCount, pageSize, *%BI*p
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startIndex); JLn<,Gn)<\
return ps; %"fKZ
} *9wHH-#
}, true); U {!{5l:
} ^}\R]})w"
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public List findAllByCriteria(final s4k%ty}
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DetachedCriteria detachedCriteria){ ebK
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return(List) getHibernateTemplate X6
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().execute(new HibernateCallback(){ 0 d]G
publicObject doInHibernate ^ w1R"qE"m
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(Session session)throws HibernateException { 0Ch._~Q+20
Criteria criteria = n9-[z2n
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detachedCriteria.getExecutableCriteria(session); 0lN8#k>H
return criteria.list(); :[03upyS
} |:[vpJFK
}, true); P?7b,a95O
} a[ l5k
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public int getCountByCriteria(final [
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DetachedCriteria detachedCriteria){ ^`?>
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Integer count = (Integer) HE'8
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getHibernateTemplate().execute(new HibernateCallback(){ XjU; oh4:.
publicObject doInHibernate 1]`HX=cl
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(Session session)throws HibernateException { [nD4\x+
Criteria criteria = XePBA
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detachedCriteria.getExecutableCriteria(session); X
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return Q6>( Z
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criteria.setProjection(Projections.rowCount HpAZ{P7
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()).uniqueResult(); W7"sWaOhW
} !{;RtUPz*
}, true); e[!>ezaIY
return count.intValue(); WQL`;uIX
} ;d40:q<
} ro@BmRMW
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用户在web层构造查询条件detachedCriteria,和可选的 =1capix 1r
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 TKX# /
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PaginationSupport的实例ps。 .`].\Zykf
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ps.getItems()得到已分页好的结果集 1[]cMyV
ps.getIndexes()得到分页索引的数组 DUr1s]+P
ps.getTotalCount()得到总结果数 -2_$zk*n
ps.getStartIndex()当前分页索引 zPYa@0I
ps.getNextIndex()下一页索引 ?2;G_P+
ps.getPreviousIndex()上一页索引 )I4t l/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 i$bBN$<b<
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 sTz*tSwQv
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一下代码重构了。 H"l'E9k.&p
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我把原本我的做法也提供出来供大家讨论吧: ~T~v*'_h
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首先,为了实现分页查询,我封装了一个Page类: ./'n2$^3
java代码: !TFVBK
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/*Created on 2005-4-14*/ aJ5R0Y,
package org.flyware.util.page; cw\a,>]H
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/** rGWTpN
* @author Joa Xk$lQMwZ
* .w~USJ=X
*/ )EoG@:[
publicclass Page { BR'|hG
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/** imply if the page has previous page */ u+_#qk0NfK
privateboolean hasPrePage; uM8gfY)OI
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/** imply if the page has next page */ Up&q#vqIj
privateboolean hasNextPage; /v[-KjTj7
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/** the number of every page */ _c2#
privateint everyPage; ;l'I.j
cx|j
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/** the total page number */ $/H'Dt6x
privateint totalPage; G.}yNjL8
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/** the number of current page */ Ou^dI
privateint currentPage; U VT8TN-T
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/** the begin index of the records by the current ~CA+'e%~~
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query */ )zN
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privateint beginIndex; $gNCS:VG*
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{
/** The default constructor */ iYf4 /1IG,
public Page(){ FyEl@ }W
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} SxDE3A-:
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/** construct the page by everyPage TI332,eL
* @param everyPage _MU'he^W
* */ P*SXfb"HC
public Page(int everyPage){ aI{[W;43T
this.everyPage = everyPage; RC 48e._t
} ~&x%;cnv_
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/** The whole constructor */ JI&>w-~D
public Page(boolean hasPrePage, boolean hasNextPage, ezn>3?S
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int everyPage, int totalPage, D1f=f88/}
int currentPage, int beginIndex){ -n9e-0
this.hasPrePage = hasPrePage; Hpt)(Nz:
this.hasNextPage = hasNextPage; AS7!FD6b
this.everyPage = everyPage; HZT;7<
this.totalPage = totalPage; 4v>V7T.
this.currentPage = currentPage; Lh}he:k+
this.beginIndex = beginIndex; wb}tN7~Y;
} 9YJb~tuZ73
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/** J: LSGj;R
* @return i"'k|TGW^
* Returns the beginIndex. ^6*? a9jO>
*/ 1jL?z6S
publicint getBeginIndex(){ 1pV"<,t
return beginIndex; R/#*~tPi8
} MWl@smRh
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/** iB?@(10}ES
* @param beginIndex Ur`v*LT}~
* The beginIndex to set. =9c24j
*/ (:\hor%
publicvoid setBeginIndex(int beginIndex){ 6-3l6q
this.beginIndex = beginIndex; \;3r
} B$bsh.
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/** 5?b9[o+D
* @return 9K49<u0O
* Returns the currentPage. c_iF S
*/ \c]/4C +/
publicint getCurrentPage(){ 1$^{Uma
return currentPage; 8p
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} R:e:B7O~0
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/** [ACYd/
* @param currentPage G2A pm`/ y
* The currentPage to set. qSQjAo4t@
*/ 3!,%;Vz=
publicvoid setCurrentPage(int currentPage){ {\V)bizY;
this.currentPage = currentPage; DirWe
} t3M/ThIE
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/** ESO(~X+
* @return IQM!dC
* Returns the everyPage. Cxh9rUe.
*/ V><P`
publicint getEveryPage(){ y?rsfIth`
return everyPage; s#Le`pGoW
} Ev()2 80
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/** ;'h7
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* @param everyPage r=9*2X#
* The everyPage to set. )S%mKdOm
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*/ t`LH\]6@
publicvoid setEveryPage(int everyPage){ xWD wg@ P
this.everyPage = everyPage; ?*T`a oB
} gs!{'=4wT
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/** L]p:gI{m
* @return VHJr+BQ1K/
* Returns the hasNextPage. }LM_VZj
*/ A$5T3j'
publicboolean getHasNextPage(){ qb! vI3
return hasNextPage; MB#%k#z`B
} 53L)+\7w
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/** &pCKz[Yf+
* @param hasNextPage ^WeT3b q
* The hasNextPage to set. dWp4|r
*/ i->sw#
publicvoid setHasNextPage(boolean hasNextPage){ HP7Ec
this.hasNextPage = hasNextPage; =v_ju;C=
} T1x$v,)8x
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/** tHGK<rb
* @return qYpHH!!C=
* Returns the hasPrePage. x[vX|oE!A
*/ mU3UQ
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publicboolean getHasPrePage(){ )QX9T
return hasPrePage; mV;7SBoT
} B^6P6,
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/** Yux7kD\c
* @param hasPrePage DF|qNX
* The hasPrePage to set. )ow 3Bl8w
*/ [X-Q{c4
publicvoid setHasPrePage(boolean hasPrePage){ "aP/214Ul
this.hasPrePage = hasPrePage; -Wmpj
} P017y&X
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/** ^wX_@?aKtt
* @return Returns the totalPage. r}vrE
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* Pd3t~1TaW
*/ >LW9$[H
publicint getTotalPage(){ D.HAp+lx
return totalPage; >6aCBS?2
} 9/nL3 U@i1
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/** 9
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* @param totalPage :!3P4?a
* The totalPage to set. L\b$1U!i
*/ 9_HEImk
publicvoid setTotalPage(int totalPage){ 7ed*dXY*
this.totalPage = totalPage; =B;)h
} MHgS5b2
>`6^1j(3
} g'mkhF(
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y
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ?"L>jr(
9 /9,[ A
个PageUtil,负责对Page对象进行构造: Tp9LBF
java代码: x[)S3UJ
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/*Created on 2005-4-14*/ (V
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package org.flyware.util.page; /]YK:7*98
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import org.apache.commons.logging.Log; jSddjs
import org.apache.commons.logging.LogFactory; o XGf#>keg
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/** /A_
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* @author Joa #M_QSD}&
* <,LeFy\zW
*/ b?r0n]
publicclass PageUtil { 6H3_qx
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privatestaticfinal Log logger = LogFactory.getLog P{);$e+b~
yLI=&7/e@
(PageUtil.class); d{YhKf#~
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/** 5xRh'Jkyb
* Use the origin page to create a new page i~\gEMaO
* @param page M>0~Ek%3
* @param totalRecords xE + Go
* @return zmuq4-.
*/ U;;Har
publicstatic Page createPage(Page page, int Qi[T!1
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totalRecords){ Ad]r )d{
return createPage(page.getEveryPage(), 0}aJCJ9sx=
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page.getCurrentPage(), totalRecords); 0V1kZ.
} o]jo R3
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/** :pNZQX
* the basic page utils not including exception >+8mq]8^
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handler dkCSqNFL)
* @param everyPage 8_KXli}7=
* @param currentPage ."3 J;j
* @param totalRecords 5|AZ/!rb
* @return page Ju:=-5r"'
*/ dAga(<K
publicstatic Page createPage(int everyPage, int 89WuxCFS
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currentPage, int totalRecords){ 2wu
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everyPage = getEveryPage(everyPage); m@jOIt!<
currentPage = getCurrentPage(currentPage); +L_.XToq-
int beginIndex = getBeginIndex(everyPage, &npf
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currentPage); q.MM|;_u`
int totalPage = getTotalPage(everyPage, FmnA+fA
S>**hMU%
totalRecords); HI:E&20y
boolean hasNextPage = hasNextPage(currentPage, b"x:IDW qG
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totalPage); az`5{hK
boolean hasPrePage = hasPrePage(currentPage); 15 SIZ:Q
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returnnew Page(hasPrePage, hasNextPage, '"I"D9;9
everyPage, totalPage, O1/!)E!
currentPage, @^`-VF
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beginIndex); ay4|N!ExO
} Wlt shZo
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privatestaticint getEveryPage(int everyPage){ e_,_:|t
return everyPage == 0 ? 10 : everyPage; #&DJ3(T
} .%D] z{''
#He:p$43
privatestaticint getCurrentPage(int currentPage){ J,jl(=G
return currentPage == 0 ? 1 : currentPage; _Hkc<j/e~
} =#1/<q)L
po{f*}gas]
privatestaticint getBeginIndex(int everyPage, int ?t<wp3bZ
W/J3sAYv
currentPage){ q^,^tw
return(currentPage - 1) * everyPage; UY>{e>/H9
} 78 3a Z8
>o(*jZ
privatestaticint getTotalPage(int everyPage, int CuDU~)`
SR8[
7MU
totalRecords){ F[9IHT6{
int totalPage = 0; SU x\qz)
*6k
(xL
if(totalRecords % everyPage == 0) c?wFEADn
totalPage = totalRecords / everyPage; Kz 'W
|
else ujDAs%6MZ
totalPage = totalRecords / everyPage + 1 ; S,J'Z:spf
M~3(4,
return totalPage; u*H2kn[DU
} `t#C0
3{,Mpb@
privatestaticboolean hasPrePage(int currentPage){ spAYb<
return currentPage == 1 ? false : true; k
\]@
} Be-gGJG
=(zk-J<nY
privatestaticboolean hasNextPage(int currentPage, `(16_a
G.c s-f
int totalPage){ W>s<&Vb
return currentPage == totalPage || totalPage == EEF}Wf$f
~|?2<g$gYR
0 ? false : true; UlQ }
} !74*APPHR
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VRMlr.T+
} K@W~
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.8g&V|
D|UDLaz~
<:/V`b3a
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。 >>&~;PG[
[<OMv9(l'o
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 }8 ,b;Q
!'n+0
做法如下: Qg1LT8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 cj5pI?@e)
:qw:)i
的信息,和一个结果集List: \b~zyt6-
java代码: -!7QH'
VSM%<-iQ
|h8C}P&Z
/*Created on 2005-6-13*/
c9DX
package com.adt.bo; 6V!yfps)
E&]S No<
import java.util.List; :90DS_4
$g5pKk
import org.flyware.util.page.Page; Rm6<"SLV
"PnYa)?1
/** _U'edK]R
* @author Joa 8=t?rA
*/ vR#A7y @!
publicclass Result { Y|KX:9Y@
|A &Nv~.)
private Page page; &Gxk~p<
`[Kh[|
private List content; .LV=Z0ja
7*u0)Hog
/** !/Hln;{
* The default constructor 'g( R4deCX
*/ 4 YI,:
public Result(){ -.:1nI
super(); XWk/S $-d
} Tf*X\{"
|+ @
/** p5>TL!4M
* The constructor using fields mN*9X[>x
* l{Xsh;%=
* @param page c]&(h L
* @param content &ViIxJZ1$
*/ b-%7@j
public Result(Page page, List content){ 3-tp94`8}t
this.page = page; J:pnmZ`X
this.content = content; >q4nQ/eP
} #S_LKc
;I]TM#qGF
/** W:hR81ci
* @return Returns the content. E$*I.i_m
*/ &<k)W
publicList getContent(){ F0]= z-
return content; E70
}
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69\0$O
/** ! =I:Uc-Y
* @return Returns the page. pO=bcs8Z
*/ 0nG&
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public Page getPage(){ <)y'Ot0 y
return page; z{;W$SO
2
} O:pQf/Xn
nvgo6*
/** aD24)?db-
* @param content H~@aT7
* The content to set. &UQKZ.
*/ Pbd#Fu;
public void setContent(List content){ $Iv*?S"2
this.content = content; j@2-^q:`
} G8f7N;D
rTW1'@E
/** [ZDJs`h!`
* @param page I3s'44
* The page to set. i1 C]bUXA
*/ I-&/]<5y
publicvoid setPage(Page page){ Lp1wA*
this.page = page; RhX
2qsva-
} TDy@Y>
)
} li,kW`j+t
eAm7*2
&Lk@Xq1
Sg')w1
32YE%
2. 编写业务逻辑接口,并实现它(UserManager, />.&
7u o4F=%
UserManagerImpl) mpK|I|-
java代码: f}nGWV%,
(;C_>EL&u
\MK)dj5uUJ
/*Created on 2005-7-15*/ .#rI9op
package com.adt.service; /O/u5P{J
z}OY'}sk8
import net.sf.hibernate.HibernateException; &!KJrQ
Wb/@~!+i`
import org.flyware.util.page.Page; rx|/]NE;
JnV$)EYi
import com.adt.bo.Result; - stSl*
ur9 -F^$
/** >Py; 6K
* @author Joa ~O|j*T
*/ tJ2l_M^
publicinterface UserManager { 69O?sIk
y)Ip\.KV\
public Result listUser(Page page)throws E5-8tHV
r(%#@?&
HibernateException; ax7ub
9tk}_+
} an0@EkZ
T*|?]k
8@*
3)__b:7J
QBai;p{
.:l78>f
java代码: .Uha %~%
aH,0+ |
lt5~rH2
/*Created on 2005-7-15*/ =xai 7iM
package com.adt.service.impl; U>ob)-tl
\muyL?
import java.util.List; B~LB^
n(>@
-wvJZ
import net.sf.hibernate.HibernateException; b>Vs5nY!
pd>EUdbrp&
import org.flyware.util.page.Page; BU]9eF!>h
import org.flyware.util.page.PageUtil; @*A(#U8p3
O_(J',++
import com.adt.bo.Result; 1B,RRHXn6
import com.adt.dao.UserDAO; /HI#8
import com.adt.exception.ObjectNotFoundException; SYa!IL-B
import com.adt.service.UserManager; 2R:['QT
_EjS(.e/=
/** /`:5#O
* @author Joa _pjpPSV6J
*/ s:w LEj+
publicclass UserManagerImpl implements UserManager { cg$7`/U
]5rEwPB
private UserDAO userDAO; qhL e[[>
pz.<5
/** j31
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* @param userDAO The userDAO to set. yd`.Rb&V
*/ f0MHh5
publicvoid setUserDAO(UserDAO userDAO){ R"=G?d)
this.userDAO = userDAO; @qg=lt|(F
} 1fEV^5I
V"T;3@N/4
/* (non-Javadoc) .CwMxuW
* @see com.adt.service.UserManager#listUser vV8y_
kmo3<'j{
(org.flyware.util.page.Page) -L1{0{Z
*/ ;Q?
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public Result listUser(Page page)throws N ?0V0B
rs 7R5 F
HibernateException, ObjectNotFoundException { A%%WPBk{O
int totalRecords = userDAO.getUserCount(); rw8db'
if(totalRecords == 0) oNl_r: G
throw new ObjectNotFoundException $;$_N43
GJ{]}fl
("userNotExist"); :mY(d6#A>
page = PageUtil.createPage(page, totalRecords); \u",bMQF
List users = userDAO.getUserByPage(page); 6dq5f?w]
returnnew Result(page, users); A3M)yW q
} 0m51nw~B
a"#5JcR3
} UO>p-M
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YX@[z
5*
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R &T(S
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q4_j`q
g%[lUxL
询,接下来编写UserDAO的代码: E]_sl/`{od
3. UserDAO 和 UserDAOImpl:
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java代码: "mHSbG
pkBmAJb@
a?\
Au
/*Created on 2005-7-15*/
V4ayewVX
package com.adt.dao; M^k~w{
+r4^oT[-
import java.util.List; GZ*cV3Y`&
Q6"r^wWx
import org.flyware.util.page.Page; F9-xp7T
8Qek![3^
import net.sf.hibernate.HibernateException; f>l}y->-Ug
,58D=EgFy
/** k((_~<$2K
* @author Joa v:s~Y
*/ [ V/*{Z
publicinterface UserDAO extends BaseDAO { tb{l(up/a
hZc$`V=R
publicList getUserByName(String name)throws mi<V(M~p
b^6Ooc/-k
HibernateException; }|AUV
%'k^aqFL
publicint getUserCount()throws HibernateException; oy#Qj3M8=
g2w0#-
publicList getUserByPage(Page page)throws b@z/6y!
hPD2/M
HibernateException; dhsQfWg#}
}3=]1jH6
} ),dXaP[
z.P)
:Er
v\0[B jhL?
W[w8@OCNf
h ej
java代码: 1r|'n aiZ
oT%~)g
Pou`PNvH
/*Created on 2005-7-15*/ ]"{K5s7
package com.adt.dao.impl; iS=}| 8"
4CfPa6_
import java.util.List; }(20MW8rMc
j`='SzVloW
import org.flyware.util.page.Page; hJ+>Xm@@!
yH@W6' .
import net.sf.hibernate.HibernateException; ^hRos
import net.sf.hibernate.Query; lUUeM\
|4ONGU*`E
import com.adt.dao.UserDAO; 0rjxWPc
7L? ~;;L$
/** {b=]JPE
* @author Joa 2c_#q1/Z/
*/ zF3fpEKe
public class UserDAOImpl extends BaseDAOHibernateImpl |jO&qT]{
OUS@)Tyh
implements UserDAO { QJ-6aB
*|a_(bQ4@
/* (non-Javadoc) -:AknQq
* @see com.adt.dao.UserDAO#getUserByName y]+i.8[
\ C~Y
(java.lang.String) /i"L@t)\t
*/ YeptYW@xfw
publicList getUserByName(String name)throws E@Q+[~H }
^MKvZ DOP
HibernateException { 9ZeTS~i
String querySentence = "FROM user in class ~X*)gS-=
mp+
%@n.;
com.adt.po.User WHERE user.name=:name"; ja#E}`wC4
Query query = getSession().createQuery W;eHDQ|
W`C2zbC
(querySentence); '
DCrSa>
query.setParameter("name", name); Qpe&_.&RE
return query.list(); ^CDQ75tR
} E[)`+:G]
Qf6Vj,~N
/* (non-Javadoc) gle_~es'K
* @see com.adt.dao.UserDAO#getUserCount() CES^
c-. k
*/ 7=aF-;X3jj
publicint getUserCount()throws HibernateException { S
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int count = 0; Wg3y
y8vIW
String querySentence = "SELECT count(*) FROM `Q' 0l},
0ua.aL'
user in class com.adt.po.User"; Y2"X;`<
Query query = getSession().createQuery )apqL{u:=
Gp6|M2Vu_5
(querySentence); b(wW;C'#0p
count = ((Integer)query.iterate().next 9EIHcUXe
,mx>)}l95
()).intValue(); )k.;.7dXe
return count; b$l@Z&[]
} +DY% Y
`0
4ac2^`
/* (non-Javadoc) {AoH
* @see com.adt.dao.UserDAO#getUserByPage ;*{y!pgb
n?
e&I>1W
(org.flyware.util.page.Page) t$m268m~
*/ y9cW&rDH
publicList getUserByPage(Page page)throws hl(M0cxEWP
' jf$3
HibernateException { "W?<BpV~@!
String querySentence = "FROM user in class +ng8!k
{r?O>KDQf(
com.adt.po.User"; `b=?z%LuT
Query query = getSession().createQuery W>.KV7
F3HpDfy
(querySentence); /59jkcA+
query.setFirstResult(page.getBeginIndex()) Gg]>S#^3
.setMaxResults(page.getEveryPage()); Gc^w,n[E
return query.list(); NuRxk eEO
} 6FFQoE|n
KB0HM
} 82nQ]
AcqsXBKd
O(2)A>}
-NHA{?6r
swss#?.se
至此,一个完整的分页程序完成。前台的只需要调用 s5F,*<
s2FJ^4
userManager.listUser(page)即可得到一个Page对象和结果集对象 z@R:~
8J-$+ ;
的综合体,而传入的参数page对象则可以由前台传入,如果用 :G=N|3
0,a\vs%@X
webwork,甚至可以直接在配置文件中指定。 ]?whx&+
8=Xy19<;t
下面给出一个webwork调用示例: s.d }*H-o
java代码: d~M;@<eD
M0YV Qa
4D=p#KZ
/*Created on 2005-6-17*/ gXBC=
?jl
package com.adt.action.user; Q x}\[
>k)}R|tJ
import java.util.List; &ejJf{id
!ba /]A/
import org.apache.commons.logging.Log; Cbv$O o*
import org.apache.commons.logging.LogFactory; }pxMO? h$
import org.flyware.util.page.Page; *p0n{F9
K;^$n>Y
import com.adt.bo.Result; "#anL8
import com.adt.service.UserService; D/[(}o(
import com.opensymphony.xwork.Action; Nj4=
-'ePx f
/** R >f$*T
* @author Joa 9.:r;H G
*/ G;#-CT
publicclass ListUser implementsAction{ ?WyL|;b*
wQ]!Y?I
privatestaticfinal Log logger = LogFactory.getLog |3j'HN5S
n]c6nX:'
(ListUser.class); 0%$E^`
{>$i)B
private UserService userService; o?%1^6&HE
US3rkkgDO
private Page page; lMoi5q
`/$yCXy
privateList users; :)hS-*P
+0)s{?
/* hUN]Lm6M
* (non-Javadoc) AWsy9
* >1u!(-A
* @see com.opensymphony.xwork.Action#execute() tl5}#uJ
*/ Qa-]IKOs
publicString execute()throwsException{ YL*yiZ9
Result result = userService.listUser(page); 4&]Sb}
page = result.getPage(); `L n,qiA
users = result.getContent(); .;nU"
a3'
return SUCCESS; I.#V/{J
} /<ODP6Yy;
GxjmHo
/** BSU%.tmI
* @return Returns the page. 8ExEhBX8
*/ )%H@.;cD_r
public Page getPage(){ k<xPg5
return page; [HNWM/ff7+
} =qG%h5]n
cXP*?N4Cf
/** ffDh0mDN
* @return Returns the users. !Q(x A,p
*/ aLa{zB
publicList getUsers(){ kC:GEY<N:Q
return users; O.OPIQ=?:w
} ]rk8Jsg
y*ux7KO
/** C(/{53G(
* @param page m+&)eQ:
* The page to set. ~\HGV+S!g}
*/ N_<wiwI<
publicvoid setPage(Page page){ L>:YGM"sL
this.page = page; D3,9X#B=
} fH{ _X
5ZpU><