Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 B%Yb+M&K
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 A&5$eGe9
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 rrSA.J{
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 55oLj.l^j
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分页支持类: jkNZv. )p
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java代码: 0 EXAdRR
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package com.javaeye.common.util; \Mlj
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import java.util.List; e7L;{+XI
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publicclass PaginationSupport { su=.4JcK
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publicfinalstaticint PAGESIZE = 30; d1j v>tu
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privateint pageSize = PAGESIZE; j.CC.[$g
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privateList items; Pr<?E[
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privateint totalCount; O!f* @
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privateint[] indexes = newint[0]; kXX RMR
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privateint startIndex = 0; `T9<}&=!
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public PaginationSupport(List items, int 4
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totalCount){ GZ'hj_2%<
setPageSize(PAGESIZE); <6apv(2a
setTotalCount(totalCount); g6W.Gl"5\w
setItems(items); y+:<
setStartIndex(0); "E2
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} .
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public PaginationSupport(List items, int 6-X7C9`C
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totalCount, int startIndex){ n6o}$]H
setPageSize(PAGESIZE); 71 /6=aq>n
setTotalCount(totalCount); <E\BKC%M
setItems(items); sZ4H\
setStartIndex(startIndex); r9vC&pWZ
} |E7]69=P
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public PaginationSupport(List items, int [1vrv(u>
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totalCount, int pageSize, int startIndex){ I3s}t$`y(
setPageSize(pageSize); _ve7Is`/
setTotalCount(totalCount); -`?V8OwY]
setItems(items); sox90o 7
setStartIndex(startIndex); F37,u|
} 9) YG)A~<
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publicList getItems(){ V
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return items; AARhGx|L<
} wOk:Q4OjL
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publicvoid setItems(List items){ Y0hL_46>
this.items = items; H{GbOI.
} cL
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publicint getPageSize(){ uPp(l4(+
return pageSize; 0^[$0]Mt[
} fg1 zT~
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publicvoid setPageSize(int pageSize){ yz+r@I5
this.pageSize = pageSize; uC;@Yi8
} L"b5P2{c
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publicint getTotalCount(){ ):[[Ch_
return totalCount; $Y4
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} ?NwFpSB2
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publicvoid setTotalCount(int totalCount){ r-V./M@L
if(totalCount > 0){ l;;:3:
this.totalCount = totalCount; l`u*,"$
int count = totalCount / eeX)JC0A
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pageSize; -J6}7>4^8}
if(totalCount % pageSize > 0) g+CHF?O
count++; }gn0bCJy
indexes = newint[count]; @O(\TIg
for(int i = 0; i < count; i++){ ``\H'^{B
indexes = pageSize * 7:;V[/
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} v]1rH$
}else{ qj/P4 *6E
this.totalCount = 0; ~\_E%NR
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} :dj@i6
} bVrvb`0
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publicint[] getIndexes(){ & 3a+6!L[
return indexes; l%:_#1?isf
} >pYgF=J
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publicvoid setIndexes(int[] indexes){ BdYh:
this.indexes = indexes; 4q~E\l|.5
} &Y&zUfA
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publicint getStartIndex(){ c*W$wr
return startIndex; .KD07
} YJ0[BcZ
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publicvoid setStartIndex(int startIndex){ 2,fB$5+
if(totalCount <= 0) 8L@di Y
this.startIndex = 0; xphqgOc12,
elseif(startIndex >= totalCount) Owr`ip\
this.startIndex = indexes G@;aqe[dB
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[indexes.length - 1]; Nf~<xK
elseif(startIndex < 0) R}]FIu
this.startIndex = 0; |
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else{ nk{1z\D{
this.startIndex = indexes ZAP+jX;
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[startIndex / pageSize]; v$c D!`+k
} Ob6vg^#
} ibq@0CR
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publicint getNextIndex(){ ~:@H6Ke[
int nextIndex = getStartIndex() + 4j*}|@x
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pageSize; :)z_q!$j
if(nextIndex >= totalCount) B?M+`;
return getStartIndex(); y/FisX
else )v9[/
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return nextIndex; 7-dwr?j7
} BAhC-;B#R
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publicint getPreviousIndex(){ 7~16letQ
int previousIndex = getStartIndex() - anvj{1
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pageSize; d.Z]R&X08
if(previousIndex < 0) r~TT c)2
return0; MXy{]o_H~
else Q^k#?j#
return previousIndex; (gZ!o_
} !2Orklzd1
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} *t_&im%E
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抽象业务类 Vo%d;>!G\;
java代码: $o/>wgQY-
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/** g|P hNo
* Created on 2005-7-12 1@WGbORc*
*/ 82X.
package com.javaeye.common.business; ^Toi_
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import java.io.Serializable; cabN<a
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import java.util.List; ^6+x0[13
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import org.hibernate.Criteria; xeI{i{8
import org.hibernate.HibernateException; :3B\,inJ
import org.hibernate.Session; qo@dFKy
import org.hibernate.criterion.DetachedCriteria; BGX@n#:
import org.hibernate.criterion.Projections; Xo`1#6xsE
import #*!$!c{
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org.springframework.orm.hibernate3.HibernateCallback; Iqsk\2W]a3
import zqh{=&Tjx
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org.springframework.orm.hibernate3.support.HibernateDaoS L|X5Ru
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upport; MxR U6+a
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import com.javaeye.common.util.PaginationSupport; /<0D
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public abstract class AbstractManager extends blcKtrYg
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HibernateDaoSupport { 3ZlI$r(
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privateboolean cacheQueries = false; QCR-l xO1
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privateString queryCacheRegion; opMUt,4
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publicvoid setCacheQueries(boolean d8HB2c5y0i
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cacheQueries){ SbZt\a 8
this.cacheQueries = cacheQueries; cA?
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} |L;psK
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publicvoid setQueryCacheRegion(String K;[%S
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queryCacheRegion){ [+g@@\X4
this.queryCacheRegion = wkD:i 2E7
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queryCacheRegion; jJZsBOW[8
} fm%RNAPvc
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publicvoid save(finalObject entity){ N?;o_^C
getHibernateTemplate().save(entity); `mjx4Lb
} 7[g;|(G0
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publicvoid persist(finalObject entity){ ).C!
getHibernateTemplate().save(entity); Wk\@n+Q{]
} H@E ")@92
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publicvoid update(finalObject entity){ GQ2PmnV+
getHibernateTemplate().update(entity); 8e!DDh
} KC:4
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publicvoid delete(finalObject entity){ T:dm0i au
getHibernateTemplate().delete(entity); _AYC|R|
} j yRSEk$
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publicObject load(finalClass entity, [!@oRK=~
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finalSerializable id){ *xg`Kwl5Kl
return getHibernateTemplate().load +RV- VrV
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(entity, id); UVc<C
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} JhCkkw
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publicObject get(finalClass entity, s;2/Nc
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finalSerializable id){ (\t_Hs::a
return getHibernateTemplate().get 12sD|j
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(entity, id); ] 5v4^mk
} `n`"g<K)Q
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publicList findAll(finalClass entity){ 7TkxvSL X
return getHibernateTemplate().find("from vM7v f6
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" + entity.getName()); {Mr~%y4
} ^2^|AXNES
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publicList findByNamedQuery(finalString s
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namedQuery){ [z% ?MIT
return getHibernateTemplate zk5=Opmvh
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().findByNamedQuery(namedQuery); ,.jHV
} s`=/fvf.
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publicList findByNamedQuery(finalString query, MJ*]fC3/
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finalObject parameter){ cZr G:\A
return getHibernateTemplate hyb +#R
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().findByNamedQuery(query, parameter); $iqi:vY
} %gu$_S
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publicList findByNamedQuery(finalString query, P$18Xno{
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finalObject[] parameters){ :vK(LU0K
return getHibernateTemplate NdsX*o@a
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().findByNamedQuery(query, parameters); vZE|Z[M+<
} 9G#8%[W
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publicList find(finalString query){ px_s@>l`
return getHibernateTemplate().find ~J1;tZS
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(query); N(:nF5>_
} mT6q}``vtG
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publicList find(finalString query, finalObject Jf?S9r5 Q
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parameter){ K)/!&{7n}a
return getHibernateTemplate().find %e
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(query, parameter); \ I^nx+l
} -4e)N*VVu
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public PaginationSupport findPageByCriteria {jOzap|
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(final DetachedCriteria detachedCriteria){ K[uY+!'1
return findPageByCriteria ZU-4})7uSB
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); LAv:+o(m/
} "Su
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public PaginationSupport findPageByCriteria E+}GxFG-:
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(final DetachedCriteria detachedCriteria, finalint Cs:+93w
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startIndex){ B;z;vrrL
return findPageByCriteria @sw9A93A
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(detachedCriteria, PaginationSupport.PAGESIZE, {gFAvMj#
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startIndex); nTys4R
} 3s` V)aXP
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public PaginationSupport findPageByCriteria EqD^/(,L2
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(final DetachedCriteria detachedCriteria, finalint ?}'N_n ys
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pageSize, ;w`sz.
finalint startIndex){ *A?8F"6>
return(PaginationSupport) 5LQk8NPh
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getHibernateTemplate().execute(new HibernateCallback(){ Z+Yeg
publicObject doInHibernate (9mbF%b
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(Session session)throws HibernateException { :`0'GM" `
Criteria criteria = N;-/w ip
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detachedCriteria.getExecutableCriteria(session); >u=%Lz"J
int totalCount =
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((Integer) criteria.setProjection(Projections.rowCount 8P,l>HA
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()).uniqueResult()).intValue(); K;oV"KRK
criteria.setProjection o]Z
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(null); i@P 9EU
List items = <7=&DpjI7F
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criteria.setFirstResult(startIndex).setMaxResults O(VxMO
}@Xh xZu
(pageSize).list(); +J|+es
PaginationSupport ps = ,*/Pg52?
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new PaginationSupport(items, totalCount, pageSize, Q_ctX|.
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startIndex); 8h2D+1,PZC
return ps; OmB
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} ,H>W:O
}, true); Z6
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} O\6vVM[
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public List findAllByCriteria(final h`=r)D
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DetachedCriteria detachedCriteria){ ?4^};wDb2
return(List) getHibernateTemplate ,09DBxQq,
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().execute(new HibernateCallback(){ gs?8Wzh90*
publicObject doInHibernate 4~!Eje!
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(Session session)throws HibernateException { O?CdAnhQc`
Criteria criteria = d]U`?A,
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detachedCriteria.getExecutableCriteria(session); 6`acg'sk>
return criteria.list();
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} K[kds`
}, true); a$d:_,\"
} Zr=ib
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public int getCountByCriteria(final ^f9>l;Lb
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DetachedCriteria detachedCriteria){ OY: u',T
Integer count = (Integer) >-b&v $
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getHibernateTemplate().execute(new HibernateCallback(){ 0; 7#ji
publicObject doInHibernate `|nH1sHFq
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(Session session)throws HibernateException { U_]=E<el
Criteria criteria = B`i$Wt<7
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detachedCriteria.getExecutableCriteria(session); !x>,N%~
return 69>/@<
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criteria.setProjection(Projections.rowCount 80C(H!^
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()).uniqueResult(); x|8^i6xB
} .46#`4av
}, true); `xCOR
return count.intValue(); 7'z(~3D
} _ Hc%4I
} ;`DD}j`
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用户在web层构造查询条件detachedCriteria,和可选的 YxXqI
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 U9
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PaginationSupport的实例ps。 "tUwo(K[
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ps.getItems()得到已分页好的结果集 UbO4%YHt
ps.getIndexes()得到分页索引的数组 5Tedo~v
ps.getTotalCount()得到总结果数 vwmBUix
ps.getStartIndex()当前分页索引 ++b$E&lYU
ps.getNextIndex()下一页索引 |#k@U6`SG
ps.getPreviousIndex()上一页索引 }AlYNEY
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \|.7-X
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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 yrnv!moc%t
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一下代码重构了。 vy[C'a
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我把原本我的做法也提供出来供大家讨论吧: +>SRrIi
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首先,为了实现分页查询,我封装了一个Page类: Ird|C[la
java代码: {]^O:i"
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/*Created on 2005-4-14*/ s9 @Sd
package org.flyware.util.page; .fp&MgiQ
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/** H>XFz(LWh
* @author Joa y! ~qbh[
* `:p1&OS
*/ KnGTcoXg_
publicclass Page { tlQC6Fb#
?2 f_aY ;
/** imply if the page has previous page */ '1Y\[T*
privateboolean hasPrePage; ^AL2H'
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/** imply if the page has next page */ bWmw3w
privateboolean hasNextPage; j/KO|iNL2
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/** the number of every page */ * ?]~
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privateint everyPage; PX2c[CDE^
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/** the total page number */ UG](go't
privateint totalPage; 6KRO{QK
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/** the number of current page */ g<wRN#B
privateint currentPage; n<7u>;SJQ
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/** the begin index of the records by the current _MuZ4tc
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query */ r@kP*
privateint beginIndex; ~TqT}:,H
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/** The default constructor */ SwW['c'*]B
public Page(){ jQ+sn/ROp
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} >/=> B7
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/** construct the page by everyPage R[jEvyD>(
* @param everyPage &%mXYj3y5
* */ !RH.|}
public Page(int everyPage){ /.1.MssQM
this.everyPage = everyPage; !h`kX[:
} KzV 2MO-$
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/** The whole constructor */ k|xtr&1N.!
public Page(boolean hasPrePage, boolean hasNextPage, hgj <>H|
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int everyPage, int totalPage, yN6>VD{F
int currentPage, int beginIndex){ Vzl^Ka'
this.hasPrePage = hasPrePage; !.TLW
this.hasNextPage = hasNextPage; :O= \<t
this.everyPage = everyPage; !EIjN
this.totalPage = totalPage; (Pbg[AY
this.currentPage = currentPage; t#i,1aHA
this.beginIndex = beginIndex; n6<V+G)T
} SUM4Di7
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/** {Ui=b+
* @return eq4C+&O&
* Returns the beginIndex. 4\M.6])_
*/ EYX$pz(x;
publicint getBeginIndex(){ $O)3q
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return beginIndex; ?OlV"zK
} 7 msAhz
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/** vVl; |
* @param beginIndex m P'^%TE
* The beginIndex to set. hrGH}CU"
*/ BV#78,8(
publicvoid setBeginIndex(int beginIndex){ [*:6oo98'
this.beginIndex = beginIndex; Pr ]Ka
} TuDE@ gq(
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/** Yz$3;
* @return $%R$G`.KM
* Returns the currentPage. &<RpWA k{
*/ ~m^ #FJu
publicint getCurrentPage(){ Xx:F)A8O
return currentPage; \</b4iR)LT
} :GpDg
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/** &0zT I?c
* @param currentPage mZz="ZLa:
* The currentPage to set. 4(Iplo*Ys@
*/ G uQ=gN
publicvoid setCurrentPage(int currentPage){ UFAL1c<V
this.currentPage = currentPage; 4k-+?L!/G
} *jIqAhs0{
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/** _j?e~w&0b
* @return _WX tB#
* Returns the everyPage. a]
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*/ jO*l3:!~ \
publicint getEveryPage(){ UhA"nt0
return everyPage; :+Om]#`Vls
} :0& X^]\
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/** 2_vbT!_
* @param everyPage B33$pUk
* The everyPage to set. ABE@n%|`
*/ :G\<y
publicvoid setEveryPage(int everyPage){ Tm_B^W}
this.everyPage = everyPage; b2b?hA'k
} <Rh6r}f
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/** Mi'8
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* @return 26T "XW'_
* Returns the hasNextPage. ]e.JNo
*/ 5%sE]Y#
publicboolean getHasNextPage(){ 2MZCw^s>
return hasNextPage; Vq;dJ%sY
} 4vBL6!z:Z
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/** ?v>ET2wD
* @param hasNextPage -46C!6a
* The hasNextPage to set. {pM?5"MMJ
*/ hW!)w
publicvoid setHasNextPage(boolean hasNextPage){ Z R/#V7Pj
this.hasNextPage = hasNextPage; 3bnS
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} z~`b\A,$
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/** S26MDLk`R3
* @return ~/.7l8)
* Returns the hasPrePage. $!&*xrrNM
*/ Reatdh
publicboolean getHasPrePage(){ S[WG$
return hasPrePage; Sb~MQ_
} #>Zzf
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/** [JF150zr
* @param hasPrePage g=I8@m
* The hasPrePage to set. E@7J:|.)R
*/ ,#pXpAz/
publicvoid setHasPrePage(boolean hasPrePage){ Um&(&?Xf
this.hasPrePage = hasPrePage; J9~g|5
} {e|[%reSkg
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/** E Cyyl
* @return Returns the totalPage. {%_L=2n6
* K tNY_&xd
*/ )7h$G-fe
publicint getTotalPage(){ rRFhGQq1m
return totalPage; 6{txm+U
} itC-4^
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/** D9M:^
* @param totalPage S~|T4q(
* The totalPage to set. @')[FEdW
*/ 9-MUX^?u
publicvoid setTotalPage(int totalPage){ 8<Hf"M
this.totalPage = totalPage; 5LOo8xN
} ,cNLkoN
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} e=.]F*:J
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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 6'Fd GS
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个PageUtil,负责对Page对象进行构造: X7rMeu
java代码: uCcYPvm
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/*Created on 2005-4-14*/ aTt12Sc
package org.flyware.util.page; '*3h!lW1.
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import org.apache.commons.logging.Log; ?nL.w
import org.apache.commons.logging.LogFactory; d@qsdYu-*
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/** d QqK^#
* @author Joa Oeok; :
* `^)jLuyu
*/ /HaHH.e
publicclass PageUtil { vd[0X;
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privatestaticfinal Log logger = LogFactory.getLog Ig
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(PageUtil.class); 76`8=!]R
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/** .nVa[B|.
* Use the origin page to create a new page BBev<
* @param page -X"p:=;j
* @param totalRecords }R{ts
* @return \pVXimam
*/ r4SXE\
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publicstatic Page createPage(Page page, int #~
)IJ
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totalRecords){ bJX)$G
return createPage(page.getEveryPage(), J|qZ+A[z
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page.getCurrentPage(), totalRecords); hbY5l}\5
} N'GeHByIT
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/** :s7m4!EF
* the basic page utils not including exception \hx1o\
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handler ^y<<>Y'I
* @param everyPage xjKR R?
* @param currentPage GU( _
* @param totalRecords `)_dS&_\
* @return page 6;ixa
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*/ TOB]IrW
publicstatic Page createPage(int everyPage, int {A05u3}
;5659!;
currentPage, int totalRecords){ .N
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everyPage = getEveryPage(everyPage); AT2n VakL
currentPage = getCurrentPage(currentPage); 75XJL;W #
int beginIndex = getBeginIndex(everyPage, =\H!GT
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currentPage); |Uc_G13Y{D
int totalPage = getTotalPage(everyPage, xe^Gs]fm
e4 >_v('
totalRecords); .K1FKC$C
boolean hasNextPage = hasNextPage(currentPage, 8@MV%MVy$
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totalPage); V3^&oe%
boolean hasPrePage = hasPrePage(currentPage); ,F,X
,
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returnnew Page(hasPrePage, hasNextPage, 5\]Sv]s)R
everyPage, totalPage, xdp`<POn%
currentPage, R#%(5-Zu#R
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beginIndex); 7$CBx/X50)
} .\)U@L~
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privatestaticint getEveryPage(int everyPage){ E87Ww,z8
return everyPage == 0 ? 10 : everyPage; tMf}
} 3=aQG'B
LG9+y
privatestaticint getCurrentPage(int currentPage){ Vex{.Vh,"
return currentPage == 0 ? 1 : currentPage; Cv6'`",Yzm
} _V7s#_p
21K>`d\
privatestaticint getBeginIndex(int everyPage, int )48QBz?
TJK[ev};S
currentPage){ *Q?tl\E
return(currentPage - 1) * everyPage; M
l Jo`d
} _`&m\Qe>
1v.c 6~
privatestaticint getTotalPage(int everyPage, int 1Q<^8N)pf
)u[emv$
totalRecords){ A kC1z73<
int totalPage = 0; $4h 5rC g0
;f#v0W`5
if(totalRecords % everyPage == 0) J}v}~Cv
totalPage = totalRecords / everyPage; RtTJ5@V(
else |$8~?7Jv
totalPage = totalRecords / everyPage + 1 ; c;Pe/ d
zv0l,-o
return totalPage; Yc_8r+;(
} p<2L.\6"
2^h27A
privatestaticboolean hasPrePage(int currentPage){ 6dabU*
return currentPage == 1 ? false : true; J8uLJ
} v+46QK|I&
/:~\5}tW
privatestaticboolean hasNextPage(int currentPage, tn(JC%?^
,)Me
int totalPage){ MQ5R O;RY
return currentPage == totalPage || totalPage == *>7 >g"
m% -g ~q
0 ? false : true; f$e[u
Er
} HN=V"a
Dfg2`l
dJJP3}M/
} G_bG
We$:&K0
n}F&1Z
3!XjtVhK?I
$q6BP'7
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。 7K,-01-:
)h"<\%LU
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!O5quEc
uwzvb gup?
做法如下: [$0p+1
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 g!@<n1 L
q rJ`1
的信息,和一个结果集List: {XR6>]
java代码: x+Ttl4
H?<N.Dq
C'\-
@/
/*Created on 2005-6-13*/ t<#mP@Mz=N
package com.adt.bo; UQ)W%Y;[0
4|buk]9
import java.util.List; >7lx=T
x
60P#,o@G
import org.flyware.util.page.Page; `q}I"iS
_<k\FU
r
/** dgR
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* @author Joa {MtpkUN
*/ '&x#rjo#
publicclass Result { mHV%I@`Y6
CtyoHvw+M
private Page page; @e(o129
+giyX7BPJ
private List content; {@6=Q 6L
G`SUxhC k
/** 0h#lJS*
* The default constructor _ky,;9G]
*/ 5]KW^sL
public Result(){ |^: cG4e
super(); Gw>^[dmt!
} FQu8vwV6>
)Xk0VDNp$/
/** 7C,&*Ax,9
* The constructor using fields 6IBgt!=,
* Yw4n-0g
* @param page $ 7O}S.x
* @param content fol,xMc&
*/ tNO-e|~'
public Result(Page page, List content){ HJLu'KY}
this.page = page; M2PAy! J
this.content = content; `NCwK6/i
} CJ1 7n
fsJ9bQm/
/** U{7w#>V
.
* @return Returns the content. ]RPs|R?
*/ 10)jsA
publicList getContent(){ Bp_$.!Qy
return content; E(O74/2c8
} 1C<uz29
rSZd!OQ
/** 'FqQzx"r
* @return Returns the page. F~T]u2qt
*/ }Mst jm
public Page getPage(){ }#L^! \V}
return page; SX<` {x&L
} iP
=V8g?L
d74d/l1*{
/** 2)G
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* @param content 9!6f-K
* The content to set. j/R[<47
*/ Ja,wfRq
public void setContent(List content){ s3~lT.
this.content = content; -m)X]]~C
} pOGeruu?
v=0(~<7B
/** GR&z,
* @param page 6g|*`x{
* The page to set. d ^^bke$~
*/ GGNvu)"
publicvoid setPage(Page page){ Bzkoo J
this.page = page; 8K.R=
} aoTM
} dYT%
>pU$wq|i
^Y=\#-Dd
k3u"A_"c
G0/4JSH
2. 编写业务逻辑接口,并实现它(UserManager, [<2<Y
P^A!.}d
UserManagerImpl) {9?Jj A
java代码: ?ATOXy
W}m)cn3@
iL7DRQ1
/*Created on 2005-7-15*/ BUWqIdg
package com.adt.service; 0+?7EL~
OBMTgZHxv
import net.sf.hibernate.HibernateException; /j4P9y^]=
".W8)
import org.flyware.util.page.Page; <vUbv
+1uF !G&l
import com.adt.bo.Result; KV}FZ3jY
qs1 ?IYD
/** m+b):
* @author Joa ?%O(mC]u&
*/ syWG'(>
publicinterface UserManager { ~k!j+>yT
4,sJE2"[9
public Result listUser(Page page)throws \DYWy*pe
Q3
u8bx|E
HibernateException; w\(.3W7
NL!u<6y
} 0O9Ni='Tn
>OL 3H$F
/q<__N
&:/hrighH
{t0)
q
java代码: =7w\
7-.m
9Xj7~,
_kj wFq
/*Created on 2005-7-15*/ ur3(HL
package com.adt.service.impl; [NaN>BZ?
T;L>;E>B
import java.util.List; (MR_^t
zfc'=ODX
import net.sf.hibernate.HibernateException; eIz<)-7:
:ctu5{"UJ
import org.flyware.util.page.Page; _oHNkKQ
import org.flyware.util.page.PageUtil; [#l*_0
:K-~fA%kt?
import com.adt.bo.Result; Q?nN!eT
import com.adt.dao.UserDAO; W yB3ls~
import com.adt.exception.ObjectNotFoundException; qu-B|
MuOa
import com.adt.service.UserManager; PMNjn9d
)CuZDf@
/** ]!I7Y.w6
* @author Joa $*AYcy7
*/ n&"B0y cF
publicclass UserManagerImpl implements UserManager { P,xKZ{(
+_; l|uhT;
private UserDAO userDAO; -n=^U
Ont%eC\
/** zbk q
* @param userDAO The userDAO to set. ^5H >pat
*/ .$qnZWcgG
publicvoid setUserDAO(UserDAO userDAO){ <R''oEf9
this.userDAO = userDAO; F$ #U5}Q
} U&Wt%U{
p^Ak1qm~e
/* (non-Javadoc) jFASX2.p
* @see com.adt.service.UserManager#listUser S<VSn}vn
?$*SjZt
(org.flyware.util.page.Page) \MbB#
*/ eM$s v9?
public Result listUser(Page page)throws [Jogt#Fj ]
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HibernateException, ObjectNotFoundException { %/|9@e r
int totalRecords = userDAO.getUserCount(); W+PJZn
if(totalRecords == 0) HkO7R
`
throw new ObjectNotFoundException kMb}1J0i"
h-G)o[MA
("userNotExist"); _CmOd-y
page = PageUtil.createPage(page, totalRecords); YE|SKx@
List users = userDAO.getUserByPage(page); Tw""}|] g
returnnew Result(page, users); G&i!Hs
} (#Wu#F1;
1DE1.1
} $oj:e?8N
PmKeF}
%>~sJ0
KVn []@#
i+p^ ^t\
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 )TVFtI=,NN
mS~o?q-n
询,接下来编写UserDAO的代码: *v9 2
3. UserDAO 和 UserDAOImpl: j6Yy6X]
java代码: K
P Oa|$
yf[~Yl>Ogw
|y0(Q V
/*Created on 2005-7-15*/ CDP
U\ZG
package com.adt.dao; {OXFN;2
L1cI`9
import java.util.List; ZUoxMm
\6R,Nq
import org.flyware.util.page.Page; w8MG(Lq1"
t.7?
import net.sf.hibernate.HibernateException; \/: {)T~
Lv|q
/** N"]q='t
* @author Joa .NYbi@bk(<
*/ [H6hyG~
publicinterface UserDAO extends BaseDAO { a0D%k: k5
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uX7b
publicList getUserByName(String name)throws k@/sn(x
FFu9&8Y
HibernateException; ,.kha8v
CIb2J)qev
publicint getUserCount()throws HibernateException; U)E(`{p]
>8k_n
publicList getUserByPage(Page page)throws GBRa.;Kk
/atW8 `&
HibernateException; Q36qIq_0e
V:VO[e<e
} ~GL]wF2#
G LIi6
aqj@Cjk4Z
gk"$,\DI
(NF~Ck$#q
java代码: _3TY,l~
)N7Y^CN~
Qa-K$dm%
/*Created on 2005-7-15*/ _*1`@
package com.adt.dao.impl; L)@?e?9
M<kj_.
import java.util.List; umt.Um.m2
YVHm{A1b0
import org.flyware.util.page.Page; FB{KH .
-OapVa c
import net.sf.hibernate.HibernateException; ;<j0f~G`
import net.sf.hibernate.Query; yCVI\y\B
@~YYD#'vNY
import com.adt.dao.UserDAO; D/vOs[X
o,
NT e5
/** 5N/%v&1
* @author Joa ^(f"v
e#7v
*/ ^/\Of{OZ-
public class UserDAOImpl extends BaseDAOHibernateImpl ?~hHGf\^b6
Qo;zHZ'
implements UserDAO { VJickXA
u>kN1k Q8
/* (non-Javadoc) {q`jDDM
* @see com.adt.dao.UserDAO#getUserByName B9NWW6S
19E8'@
(java.lang.String) inh=WUEW
*/ apg=-^L'
publicList getUserByName(String name)throws HY&aV2|A1
A8uVK5
HibernateException { +@p%
p
String querySentence = "FROM user in class mLP.t%?#
y5*Z3"<
com.adt.po.User WHERE user.name=:name"; =a@j=
Query query = getSession().createQuery a&c6.#E{y
925|bX6I
(querySentence); \s=t|Wpu2
query.setParameter("name", name); C71qPb|$R
return query.list(); E4|jOz^j4\
} w5A y)lz
l49*<nkmq
/* (non-Javadoc) .Le?T&_
* @see com.adt.dao.UserDAO#getUserCount() WtG~('g>&
*/ @+Si?8\
publicint getUserCount()throws HibernateException { $\]&rZVi
int count = 0; El.hu%#n*G
String querySentence = "SELECT count(*) FROM C8Qa$._
]rWgSID
user in class com.adt.po.User"; S|7!{}
Query query = getSession().createQuery WvBc#s-
+nXK-g;)'
(querySentence); c:<005\Bg
count = ((Integer)query.iterate().next WST8SEzJ
Jk7|{W\OA
()).intValue(); {`LU+
return count; M>~Drul
} r:f[mk"-"A
[d(U38BI
/* (non-Javadoc) nbm&wa[
* @see com.adt.dao.UserDAO#getUserByPage 1FlX'[vh
U+:m4a
(org.flyware.util.page.Page) _+K_5IO4
*/ >7I15U
publicList getUserByPage(Page page)throws 1*'HL#
*>|gxM8
HibernateException { +
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String querySentence = "FROM user in class YG@t5j#b
9 7GV2]-M
com.adt.po.User"; =t9\^RIx)?
Query query = getSession().createQuery Cs9.&Y
8u6:=fxb
(querySentence); VH9dleZ
query.setFirstResult(page.getBeginIndex()) /{+y2.{j
.setMaxResults(page.getEveryPage()); mRL"nC
return query.list(); "D63I|O)
} +jS|2d
CG0
M
} !W5 (
qU%/W|LY
r^FhTzA=1
[fAV5U
GFeQ%l`7F
至此,一个完整的分页程序完成。前台的只需要调用 Qw-~>d
QEz?w}b*
userManager.listUser(page)即可得到一个Page对象和结果集对象 dIN$)?aB0
{1UQ/_
的综合体,而传入的参数page对象则可以由前台传入,如果用 F5P[dp-`1
-w9pwB
webwork,甚至可以直接在配置文件中指定。 Q.l}NtHwV
uJzG|$;
下面给出一个webwork调用示例: @ ;*Ksy@1O
java代码: Y$Zx,
a1C{(f)
c0,0`+2~
/*Created on 2005-6-17*/ pT=JP> nd^
package com.adt.action.user; NW]Lj>0Y
w,#>G07D
import java.util.List; em,u(#)&
"i y
import org.apache.commons.logging.Log; %zG;Q@
import org.apache.commons.logging.LogFactory; w65K[l;2
import org.flyware.util.page.Page; K2TcOFQ
CyS$|E
import com.adt.bo.Result; &]`(v}`]
import com.adt.service.UserService; ''yB5#^w(
import com.opensymphony.xwork.Action; r_
I5.gK
r[|Xy>Zj
/** ',9V|jvK
* @author Joa 't:;irLW.
*/ OI|[roMK
publicclass ListUser implementsAction{ b$N2z
9IjIIM2y
privatestaticfinal Log logger = LogFactory.getLog yA)/Q
Yge
\pPY37l
(ListUser.class); X <f8,n
[xSF6
private UserService userService; B
Wk/DVue
zr-*$1eu
private Page page; tXNm$Cq.|
!%CWZZ 6u
privateList users; e7^mmm
s'!Cp=xQF"
/* J1( 9QN[w
* (non-Javadoc) S0zD"T
* u(@$a4z
* @see com.opensymphony.xwork.Action#execute() th
*/ I(i}c~R
publicString execute()throwsException{ aOlT;h
Result result = userService.listUser(page); n&$j0k
page = result.getPage(); 6HT;#Znn
users = result.getContent(); @i2E\}
return SUCCESS; CDsSrKhx
} J l(&!?j
LInz<bc<(
/** \hTm)-FP
* @return Returns the page. &5\iM^
*/ dG@%jD)
public Page getPage(){ C[ NSkr
return page; Lt u'W22
}
?9!6%]2D
,)0H3t
/** `g(Y*uCp
* @return Returns the users. 3
}duG/
*/ \nXtH}9ZF
publicList getUsers(){ =$u!
59_dE
return users;
SWH2
} j_K4;k#r
@Xt*Snd
/** T. }1/S"m
* @param page bGN:=Y'
* The page to set. 6Y^23W F
*/ nr95YSH
publicvoid setPage(Page page){ <fZyAa3}
this.page = page; ?^7t'`zk
} aRj9E}
$Ipg&`S"
/** I@T8Iv=
* @param users Z_$%.
* The users to set. C^O
VB-
*/ =O&%c%~q
publicvoid setUsers(List users){ $mu^G t
this.users = users; HHA<IZ#;,
} 52%2R]G!
vmU@^2JSJ
/** vx1c,8
* @param userService '.on)Zd.
* The userService to set. dzARI`
*/ B-xGX$<z
publicvoid setUserService(UserService userService){ p,
h9D_
this.userService = userService; E%yNa]\P
} o*b] p-
} *QpMF/<?
SON-Z"v
+NeOSQSj
(uXL^oja
VU#`oJ:{
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, 3-[q4R
7r7YNn/?
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 'H3^e}
@ju@WY45$^
么只需要: ;ic3).H
java代码: |LRedD7n
{
d=^}-^
pM+ AjPr
<?xml version="1.0"?> 2a-w%
(K
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork )Lk639r
%>yG+Od5Z
1.0//EN" "http://www.opensymphony.com/xwork/xwork- w^?>e;/\
/$ w%Q-p
1.0.dtd"> n&L+wqJ
4;w;'3zq
<xwork> "7
4-4
dz:E?
<package name="user" extends="webwork- {Bk[rCl
P60~V"/P
interceptors"> >W%EmnLK
A}BVep@D
<!-- The default interceptor stack name +O"!qAiK
4-?C>
--> .~)q};Z
<default-interceptor-ref O[\iE5+$
zvvhFN2s
name="myDefaultWebStack"/> $ZUdT
18|m)(W
<action name="listUser" '<jyw
u#Pa7_zBj]
class="com.adt.action.user.ListUser"> #pT"BSz]
<param Vrjc~>X
*U^6u/iH
name="page.everyPage">10</param> $3W;=Id=+
<result ({
8-*
.?D7dyU l1
name="success">/user/user_list.jsp</result> w;;BSJ]+[
</action> i/65v
o@r7
n>G
</package> Hn7_FOC
s28`OKC}
</xwork> XR8,Vt)=
TcyNIx
#9B)Xx!g
J; 3{3
O%Scjm-^X
k|v3.< -
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 j?A/#
&D>G8
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Nu0C;B66
|Z|-q"Rf
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 |+"<wEKI
niiA7Ux
ySk R>y
-0d0t!
QMA%$
我写的一个用于分页的类,用了泛型了,hoho % "kPvI3Y
bH-ub2@qO
java代码: P#E &|n7DT
9"@\s$
OBk
q YC;cKv
package com.intokr.util; {i1|R"ta
9
3U_tQ&1?
import java.util.List; nxY\|@
u9:`4b
/** *]. 7dec/
* 用于分页的类<br> sW Qfr$^A
* 可以用于传递查询的结果也可以用于传送查询的参数<br> `uq8G
* A;G;^s
* @version 0.01 KLU-DCb%
* @author cheng
jPC[_g
*/ Ot$-!Y;<
public class Paginator<E> { >L|;|X!m9\
privateint count = 0; // 总记录数 @+;$jRwq
privateint p = 1; // 页编号 Jz?j[
privateint num = 20; // 每页的记录数 ;5wn67'
privateList<E> results = null; // 结果 `Y+J-EQ
o=u3&liBi
/** ~{*7"o/
* 结果总数 WKQ^NEqr3
*/ =Ee&da^MB
publicint getCount(){ ~{?_p@&n
return count; /Y*WBTV'
} 7@#>bE6
tN[L@t9#cr
publicvoid setCount(int count){ _geWE0
E
this.count = count; #m lS}~n
} 7.-V-?i
anuL1fXO
/** BoA/6FRi[
* 本结果所在的页码,从1开始 R7]l{2V#^
* TSA,WP\
* @return Returns the pageNo. KMt`XaC9e
*/ #:%&x@@c3P
publicint getP(){ {qDSPo
return p; 9 ^o-EC!_
} MtM%{=&_
y9_V
/** O7u(}$D
L
* if(p<=0) p=1 ]~844Jp
* uvgdY
* @param p h}-3\8 >
*/ oYHj~t
publicvoid setP(int p){ XoXM^*Vk
if(p <= 0) ,t}vz 7
p = 1; -_ I_W&
this.p = p; -)s qc
P
} KTK <gV9:
J%8(kWQ|
/** Us%T;gW
* 每页记录数量 g6nkZyw
*/ du+y5dw
publicint getNum(){ k2E0/ @f{k
return num; W"724fwu&
} 5&xB6|k
t4{rb,
}W
/** &6DMk-
* if(num<1) num=1 (VS5V31"
*/ `id9j
publicvoid setNum(int num){ mCRt8rY;
if(num < 1) ?m![Pg%
num = 1; PxF<\pu&
this.num = num; >AC]#'
} "X2 Vrn'
[vge56h
/** \Fl+\?~D
* 获得总页数 M=.:,wRm
*/ QpZ:gM_
publicint getPageNum(){ QS0:@.}$E)
return(count - 1) / num + 1; J5*tJoCYS
} k-Q%.o
ot@|!V
/** {-ZFp
* 获得本页的开始编号,为 (p-1)*num+1 CPgC jtY
*/ Yv
hA_v
publicint getStart(){ "b?v?V0%C
return(p - 1) * num + 1; b6W2^tr-
} |lXc0"H[o
uB |Ss
/** `/_o!(Z`
* @return Returns the results. r/& sub"X
*/ ktI/3Mb@
publicList<E> getResults(){ n 9\
C2r
return results; tc_286'x
} j0Bu-sO$w
YNYx>Ue
public void setResults(List<E> results){ og4UhP^UET
this.results = results; 5>VY LI
} dG@"!!,
`{,Dy!rL
public String toString(){ ()tp>
StringBuilder buff = new StringBuilder =,%CLS,6w
DQMHOd7g
(); cQG
+$0(
buff.append("{"); Xm+8
buff.append("count:").append(count); 'iy*^A `Y
buff.append(",p:").append(p); Nb?w|Ne(T
buff.append(",nump:").append(num); CxGx8*<X
buff.append(",results:").append *ohL&