Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ml$o5&sN
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 vfo~27T{(
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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 xId.GWY1
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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 A5w6]: f2
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分页支持类: u<&m]]*
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java代码: t
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package com.javaeye.common.util; ;9g2?-svw
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import java.util.List; 4E?Oky#}-
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publicclass PaginationSupport { S21,VpW\
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publicfinalstaticint PAGESIZE = 30; POR\e|hRT]
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privateint pageSize = PAGESIZE; !{41!O,K#
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privateList items; >lM l
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privateint totalCount; &
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privateint[] indexes = newint[0]; 2GStN74X r
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privateint startIndex = 0; 01o4Th m
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public PaginationSupport(List items, int 00U> F
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totalCount){ xn|(9#1o
setPageSize(PAGESIZE); PnG-h~Y3N
setTotalCount(totalCount); N)>ID(}F1
setItems(items); Zj4Uak
setStartIndex(0); {kAc(
} jlg(drTo
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public PaginationSupport(List items, int 5rUdv}.
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totalCount, int startIndex){ ^/=KK:n~
setPageSize(PAGESIZE); k-""_WJ~^
setTotalCount(totalCount); 7j)8Djzp|
setItems(items); sUm'
setStartIndex(startIndex); 7T'B6`-Ox
} B,fo(kG
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public PaginationSupport(List items, int XBw)H
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totalCount, int pageSize, int startIndex){ .XhrCiZ
setPageSize(pageSize); %;"y+YFdv
setTotalCount(totalCount); Ld-_,-n
setItems(items); r/*D:x|yN
setStartIndex(startIndex); wn)W
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} pcI uN
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publicList getItems(){ 9JKEw
return items; bK-N:8Z
} 7})[lL`\s
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publicvoid setItems(List items){ -1@<=jX3_
this.items = items; $
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} b\+`e b8_
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publicint getPageSize(){ ;P&OX5~V
return pageSize; E q+_&Wk
} 7i1q wRv
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publicvoid setPageSize(int pageSize){ @gXx1hEg
this.pageSize = pageSize; 8qu6.
} "G9xMffW
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publicint getTotalCount(){ MR.'t9m2L
return totalCount; 2T[9f;jM'
} zs#@jv$
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publicvoid setTotalCount(int totalCount){ S?BG_J6A7
if(totalCount > 0){ 26x[X.C:
this.totalCount = totalCount; 1 I",L&S1
int count = totalCount / {P#|zp 4C{
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pageSize; CQDkFQq-dq
if(totalCount % pageSize > 0) 1hNq8*|
count++; *bpD`s
@
indexes = newint[count]; @2v_pJy^
for(int i = 0; i < count; i++){ KdbHyg<4
indexes = pageSize * H~z`]5CN
PRE|+=w$
i; 6Sn .I1Wy
} QUQ'3
}else{ 0}dpK $.
this.totalCount = 0; 1D!<'`)AY
} #
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} WvZ8/T'x
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publicint[] getIndexes(){ Fh9h,'
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return indexes; 4#hSJ(~7S
} gt w Q-
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publicvoid setIndexes(int[] indexes){ r^ ZEImjc
this.indexes = indexes; D=&Me=$
} K8Y=S12Ti
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publicint getStartIndex(){ $\y'IQ%
return startIndex; @bP)406p
} i,9)\1R
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publicvoid setStartIndex(int startIndex){ cq4Ipe
if(totalCount <= 0) 2WYPO"q
this.startIndex = 0; fvxu#m=
elseif(startIndex >= totalCount) :tv,]05t
this.startIndex = indexes C'}KTXiRW
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[indexes.length - 1]; v^+Sh|z/
elseif(startIndex < 0) A1zjPG&]
this.startIndex = 0; Bo%NFB;
else{ ]~hk6kS8Q
this.startIndex = indexes !0mI;~q| F
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[startIndex / pageSize]; 'F#KM1s
} $5Ff1{
} ))'<_nD
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publicint getNextIndex(){ _b;{_g
int nextIndex = getStartIndex() + y7Df_|Z
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pageSize; Z!X0U7&U
if(nextIndex >= totalCount) KRDmY+
return getStartIndex(); m$T-s|SY
else WbqWG^W
return nextIndex; RQu(Wu|m.
} $[=%R`~w
J!U}iD@occ
publicint getPreviousIndex(){ S\!ana])
int previousIndex = getStartIndex() - 3"KCh\\b
nt7.?$
pageSize; "vE4E|
if(previousIndex < 0) t" Z6[XG
return0; :${HQd+
else zu|\fP
return previousIndex; (n9gkO&8"
} )
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} qR+!l(
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抽象业务类 :T
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java代码: OMg<V
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/** ThbGQ"/
* Created on 2005-7-12 zi*R`;_`,
*/ naznayy
package com.javaeye.common.business; .$)
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import java.io.Serializable; ,>+p-M8ZL
import java.util.List; WKa~[j|-K
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import org.hibernate.Criteria; a\YV3NJ/A
import org.hibernate.HibernateException; PQ$%H>{
import org.hibernate.Session; *CTlOy
import org.hibernate.criterion.DetachedCriteria; (|1A?@sJ#h
import org.hibernate.criterion.Projections; nq8C'Fo!6T
import 0$fpIz
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org.springframework.orm.hibernate3.HibernateCallback; e|WJQd4+S
import ;&-k#PE]/H
>y:,9;
org.springframework.orm.hibernate3.support.HibernateDaoS 7!TueP0Zd
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upport; 'K{Z{[s{
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import com.javaeye.common.util.PaginationSupport; tQYM&6g
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public abstract class AbstractManager extends eu|;eP-+d
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HibernateDaoSupport { !s?nJ(p
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privateboolean cacheQueries = false; VYImI>.t{
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privateString queryCacheRegion; =\:qo'l
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publicvoid setCacheQueries(boolean Opc
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cacheQueries){ iaE^a^*
this.cacheQueries = cacheQueries; TXvI4"&
} K\6u9BYG
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publicvoid setQueryCacheRegion(String s %\-E9
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queryCacheRegion){ y0.8A-2:
this.queryCacheRegion = .Cl:eu,]
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queryCacheRegion; iq( E'`d
} EkNunCls
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publicvoid save(finalObject entity){ nWYN Np?h
getHibernateTemplate().save(entity); E`de7
} n'kG] Q
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publicvoid persist(finalObject entity){ aa#Y=%^
getHibernateTemplate().save(entity); =sJ7=39
} EZ$>.iy{
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publicvoid update(finalObject entity){ ?3zc=J"t
getHibernateTemplate().update(entity); \Vy Z
} "8^
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publicvoid delete(finalObject entity){ Zxs|%bQ
getHibernateTemplate().delete(entity); !()$8
} wL
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publicObject load(finalClass entity, jiS_G%G
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finalSerializable id){ ]J$eDbaEjT
return getHibernateTemplate().load S:oi<F
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(entity, id); ;=;
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} {rH@gz|@i
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publicObject get(finalClass entity, LzXmb 7A
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finalSerializable id){ i}mVQ\j5
return getHibernateTemplate().get p#?7w
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(entity, id); :f}9($
} ,<tX%n`v=
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publicList findAll(finalClass entity){ >dG;w6y'
return getHibernateTemplate().find("from =Og)q$AL
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" + entity.getName()); _%!c+f7
} -Rd/Gx
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publicList findByNamedQuery(finalString pg.ri64H<
C|).;V&
namedQuery){ 1&)?JZhg
return getHibernateTemplate nvJf/90$
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().findByNamedQuery(namedQuery); L>W'LNXCv
} n%C>E.Tq
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publicList findByNamedQuery(finalString query, >eqxV|]i
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finalObject parameter){ v99B7VH4
return getHibernateTemplate )d1_Wm#B
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().findByNamedQuery(query, parameter); r1.nTO%
} zHL@i0>^
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publicList findByNamedQuery(finalString query, PQnF
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finalObject[] parameters){ 6[LM_eP
return getHibernateTemplate vCxD~+zf
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().findByNamedQuery(query, parameters); UAFwi%@!-q
} x:>wUhzZ
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publicList find(finalString query){ s'a/j)^
return getHibernateTemplate().find Z
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(query); BuWHX>H
} C8e
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publicList find(finalString query, finalObject K[Kh&`T
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parameter){ Xg
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return getHibernateTemplate().find !\i\}feb
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(query, parameter); hMUs"
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} GCX G/k?w:
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public PaginationSupport findPageByCriteria 8a="/J
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(final DetachedCriteria detachedCriteria){ ^G.Xc\^w:
return findPageByCriteria QM
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QP)pgAc
(detachedCriteria, PaginationSupport.PAGESIZE, 0); rI>aAW'
} 8lb%eb]U
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public PaginationSupport findPageByCriteria AW_(T\P:u
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(final DetachedCriteria detachedCriteria, finalint Q`D~5ci
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startIndex){ (TwnkXrR,
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, `'c_=<&n
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startIndex); C\nhqkn
} fX.>9H[w@~
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public PaginationSupport findPageByCriteria ZF|+W?0&%
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(final DetachedCriteria detachedCriteria, finalint lR[qqFR
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pageSize, Y"Ql!5=
finalint startIndex){ ->O2I?
return(PaginationSupport) W#BM(I
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getHibernateTemplate().execute(new HibernateCallback(){ J6%AH?Mt
publicObject doInHibernate <]4i`6{v
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(Session session)throws HibernateException { s#DaKPC
Criteria criteria = L19C<5>
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detachedCriteria.getExecutableCriteria(session); 7#U^Dx\yh
int totalCount = mG`e3X6@-
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((Integer) criteria.setProjection(Projections.rowCount 2fS[J'-o
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()).uniqueResult()).intValue(); ~aOuG5XK
criteria.setProjection ./D$dbu3
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(null); UkHY[M7;
List items = =gvBz | +
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criteria.setFirstResult(startIndex).setMaxResults OD 3f.fT
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(pageSize).list(); _~tEw.fM5
PaginationSupport ps = 0=q;@OIf
*U$!I?
new PaginationSupport(items, totalCount, pageSize, {g~bQ2wDC
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startIndex); t" 7yNs(I
return ps; ;VNMD 6H
} OhmQ,
}, true); 7&"n`@(.!
} }X_;X_\3;'
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public List findAllByCriteria(final UybW26C;aU
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DetachedCriteria detachedCriteria){ Qb; d:@9
return(List) getHibernateTemplate n?ctLbg
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().execute(new HibernateCallback(){ #8bsxx!s
publicObject doInHibernate o fMY,~w
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(Session session)throws HibernateException { u4neXYSy
Criteria criteria = a9Z%JS]
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detachedCriteria.getExecutableCriteria(session); 80 Y\|)
return criteria.list(); <~X >[PK<
} 4)4+M
}, true); wwoweztER
} ,i6RE
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public int getCountByCriteria(final ?EpSC&S\
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DetachedCriteria detachedCriteria){ ELjK0pE}-
Integer count = (Integer) #D9e$E(J^
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getHibernateTemplate().execute(new HibernateCallback(){ RQB]/D\BO
publicObject doInHibernate Gqcz<=/
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(Session session)throws HibernateException { kR@Yl Yo
Criteria criteria = 7Irau_
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detachedCriteria.getExecutableCriteria(session); :BukUket1e
return 8W+gl=C~
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criteria.setProjection(Projections.rowCount J~iBB~x.
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()).uniqueResult(); !W'Ui
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} ~!d/8?!
}, true); {(#%N5%
return count.intValue(); Hb(B?!M)
} 16EVl~LN
}
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用户在web层构造查询条件detachedCriteria,和可选的 Lru-u:
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 cx$Gic:4
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PaginationSupport的实例ps。 #4h+j%y[H
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ps.getItems()得到已分页好的结果集 NHgjRPz"
ps.getIndexes()得到分页索引的数组 n*'<uKpM
ps.getTotalCount()得到总结果数 Grz 3{U
ps.getStartIndex()当前分页索引 0 Hw-59MK
ps.getNextIndex()下一页索引 xf>z @)e
ps.getPreviousIndex()上一页索引 |nk3^;Yf
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 :9Y$'+ <&H
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 @C-dG7U.P
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一下代码重构了。 daAyx-
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我把原本我的做法也提供出来供大家讨论吧: MZSxQ8
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首先,为了实现分页查询,我封装了一个Page类: fKa\7{R
java代码: 2~p[7?sp'
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/*Created on 2005-4-14*/ ~ZlC
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package org.flyware.util.page; '7B"(dA&C
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/** rn:!dV[
* @author Joa |"$uRV=qm
* 0-3rQ~u
*/ )W&>[B
publicclass Page { 5lJ)(|_
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/** imply if the page has previous page */ Q1&P@Io$
privateboolean hasPrePage; +>g`m)?p
=KX<_;E
/** imply if the page has next page */ nxap\Lf
privateboolean hasNextPage; $
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/** the number of every page */ q1hMmMi
privateint everyPage; Q7o5R{.oJ
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/** the total page number */ dd7 =)XT+
privateint totalPage; 2#/p|$;Ec'
2$zU&p7sV
/** the number of current page */ YY4-bNj[p
privateint currentPage; 6a>H|"PNE
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/** the begin index of the records by the current >^"BEG9i:
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query */ "!Rw)=7O
privateint beginIndex; PI?j_8
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/** The default constructor */ [H"#7t.V-~
public Page(){ r<L#q)]
;? uC=o>Z{
} r7!J&8;{K
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/** construct the page by everyPage +ydm,aKk
* @param everyPage fjDpwb:x)
* */ /k"hH\Pp
public Page(int everyPage){ 8!h'j
this.everyPage = everyPage; ._p""'Sa
} 5>ST"l_ca
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/** The whole constructor */ ?9u4a_x
public Page(boolean hasPrePage, boolean hasNextPage, dTD5(}+J
qq+MBW*
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int everyPage, int totalPage, 0v"&G<J
int currentPage, int beginIndex){ Wc#:f8dr
this.hasPrePage = hasPrePage; O
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this.hasNextPage = hasNextPage; 1 2]fQkp
this.everyPage = everyPage; [7"}=9
this.totalPage = totalPage; {.#zHL
;
this.currentPage = currentPage; ZZ
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this.beginIndex = beginIndex; T }uE0Z,
} ]u&dJL
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/** G79C {|c\
* @return liNON
* Returns the beginIndex. Q.(51]'
*/ 1BD6l2y
publicint getBeginIndex(){ C?QfF{!7
return beginIndex; t,vTAq.))
} $M]%vG
zw:/!MS
/** \kwe51MQ
* @param beginIndex 8g5V,3_6
* The beginIndex to set. gB CC
*/ .Y/-8H-3v
publicvoid setBeginIndex(int beginIndex){ m(3);)d
this.beginIndex = beginIndex; 4IGxI7~27#
} W<gD6+=8
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/** Tj,Nmb>Q7'
* @return g+Ph6W
* Returns the currentPage. 6dT|;koWbm
*/ 2_olT_#
publicint getCurrentPage(){ ~{
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return currentPage; [w%#<5h
} W:ixzpQ
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/** <J# R3{
* @param currentPage fJ :jk6@
* The currentPage to set. Nz]aaoO4
*/ -iQsi4
publicvoid setCurrentPage(int currentPage){ E0bFx5e5fu
this.currentPage = currentPage; M5+W$W
} q=[U}{
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/** 6IF|3@yD
* @return [u\CD sX
* Returns the everyPage. aVK()1v]
*/ [>uwk``_
publicint getEveryPage(){ 5~yb
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return everyPage; Fi{mr*}
} ]]V^:"ne
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/** Z)v)\l9d
* @param everyPage z`9l<Q/
* The everyPage to set. {dZ8;Fy4
*/ ty;o&w$
publicvoid setEveryPage(int everyPage){ aT/KT,!
this.everyPage = everyPage; 'o8\`\'H!
} Gt.*_E
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/** k <}I<Or
* @return .5k^f5a
* Returns the hasNextPage. xDe47&qKM
*/ ]EX--d<_`
publicboolean getHasNextPage(){ 7+]F^
6
return hasNextPage; B=x~L
} 2vXGO|W
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/** Y=WR6!{
* @param hasNextPage gx&7 3f<J
* The hasNextPage to set. #y`k$20"
*/ AuM:2N2
publicvoid setHasNextPage(boolean hasNextPage){ L(Rorf~V
this.hasNextPage = hasNextPage; ~g96o81V
} E#~2wqK
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/** NFM-)Z57
* @return Pb=rFas*C
* Returns the hasPrePage. |=OpzCs
*/ b2%blQgo
publicboolean getHasPrePage(){ /op/g]O}
return hasPrePage; RQJ9MGw
} $@4e(Zrmo
l2M/,@G
/** !Ba3`B5l
* @param hasPrePage ].c@Gm_(
* The hasPrePage to set. ~)!VV)
*/ -&~IOqlui
publicvoid setHasPrePage(boolean hasPrePage){ I]UA0[8X
this.hasPrePage = hasPrePage; :Q#H(\26r
} \Em-.%c
DwC@"i.
/** iqlVlm>E
* @return Returns the totalPage. IM|Se4;x
* nvwDx*[qN
*/ J4&XPr9
publicint getTotalPage(){ |7Yvq%E
return totalPage; \Qb>:
} s2%0#6c'c
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/** Dl@{}9
* @param totalPage y#GCtkhi
* The totalPage to set. )[RpZpd`*
*/ \j/}rzo]
publicvoid setTotalPage(int totalPage){ )uuwwz
this.totalPage = totalPage; 7j{Te)"
} K-ju ,4A
,$SkaTBe
} [j1^$n 8V
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 !cv6 #:
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个PageUtil,负责对Page对象进行构造: s:G[Em1
java代码: gx&\Kw6HM
N_*u5mfQX
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/*Created on 2005-4-14*/ ]r]+yM|
package org.flyware.util.page; la1D2 lM
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import org.apache.commons.logging.Log; sd]0Hx[
import org.apache.commons.logging.LogFactory; {m>~`
/:Rn"0
/** v^57j:sD
* @author Joa 'G3+2hah
* KX$qM g1j
*/ B1up^(?
publicclass PageUtil { o4U]lK$
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privatestaticfinal Log logger = LogFactory.getLog Y|Nfwqz
X~`.}
(PageUtil.class); =ulr_i%Xs
/ N*HE
/** U=_~{[/
* Use the origin page to create a new page @5JLjCN
* @param page 'bbV<?):
* @param totalRecords nDwq!LEx%5
* @return ,Uv{dG
*/ 19pND
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publicstatic Page createPage(Page page, int Gl dH SCy
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totalRecords){ y_;]=hEL
return createPage(page.getEveryPage(), 5 >0\e_V
0]/,m4a#n
page.getCurrentPage(), totalRecords); gizmJ:<
} &T5fH!?4
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/** ^M[-K`c }
* the basic page utils not including exception M^!C?(Hx^x
n$}R/*
handler I 0x`H)DA
* @param everyPage sj?`7kg
* @param currentPage A8CIP:Z
* @param totalRecords V!j K3vc
* @return page _3-RoA'UZr
*/ 5( mCBH
publicstatic Page createPage(int everyPage, int .`i'gPLkn2
7<Z~\3x
currentPage, int totalRecords){ m? ]zomP
everyPage = getEveryPage(everyPage); Ncs4<"{$
currentPage = getCurrentPage(currentPage); )M&I)In'
int beginIndex = getBeginIndex(everyPage, *B)Jv9
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currentPage); O?+tY
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int totalPage = getTotalPage(everyPage, mgJ]@s}9
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totalRecords); P':]A{<Z
boolean hasNextPage = hasNextPage(currentPage, ^59YfC<f
[esX{6,i
totalPage); `[g#Mxw
boolean hasPrePage = hasPrePage(currentPage); N{0+C?{_
&Sa_%:*D(
returnnew Page(hasPrePage, hasNextPage, \.XT:B_
everyPage, totalPage, tk]_QX
%
currentPage, Lqz}&A
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beginIndex); ~jgN_jz
} 9Y!0>&o
;%3thm7+
privatestaticint getEveryPage(int everyPage){ 9!Q
$GE?vl
return everyPage == 0 ? 10 : everyPage; Q0[CH~
} YFC0KU
]k3GFPw
privatestaticint getCurrentPage(int currentPage){ >F
LdI
return currentPage == 0 ? 1 : currentPage; 5 O{Ip-
} { c6DT
CrQA :_Z(7
privatestaticint getBeginIndex(int everyPage, int f<$K.i
Dn{19V.L
currentPage){ ouu-wQ|(mM
return(currentPage - 1) * everyPage; :_I
wc=
} g9grfN
"'&>g4F`o
privatestaticint getTotalPage(int everyPage, int )\:lYI}Wpm
*cI6&;y
totalRecords){ !z"a_
int totalPage = 0; 3f7t%
}tl8(kjm
if(totalRecords % everyPage == 0) K2cp f
totalPage = totalRecords / everyPage; KNUMz4
else gpO_0U4lQ]
totalPage = totalRecords / everyPage + 1 ; nf+"vr}1
+Y>cBSO
return totalPage; ,]>`guDV
} Sx4UaV~"
k7Be'E
BKG
privatestaticboolean hasPrePage(int currentPage){ qQ?,|4)y
return currentPage == 1 ? false : true; *BP\6"X
} 1z$}*`
zwniS6R1
privatestaticboolean hasNextPage(int currentPage, k8t Na@H
jmZ|b6
int totalPage){ `*2*xDuP
return currentPage == totalPage || totalPage == sWpRX2{5,
b|V4Fp
0 ? false : true; D ^T7pO
} Cs~\FI1wR
L2V
$%*6
hj m.Ath
} (Db*.kd8,
.k!k-QO5La
(<:rKp
l5N\>q
A=YEY n
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 *9U4^lJjn
Xj@
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 }IalgQ(i
Q e2/4j4
做法如下: *t]&b ;=gE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 C\hZ;Z1
k0Vo
的信息,和一个结果集List: vSHIl"h
java代码: "n2xn%t{
zdpLAr
0o^#Fmuz
/*Created on 2005-6-13*/ WriJco<v
package com.adt.bo; g`f6gxc
b6E8ase:F
import java.util.List; w|UKMbRMU]
Kt&$Si
import org.flyware.util.page.Page; 1SJHX1CxX
=LeVJGF
/** /{#_Um0.
* @author Joa JEkIbf?=r
*/ (HX [bG`
publicclass Result { q.hc%s2?
:QhEu%e
private Page page; "'p+qbT8
;?L[]Ezzt
private List content; aK=3`q
vM>`CZ
/** ~D-OL*2
* The default constructor xYkgNXGs5
*/ @x>$_:]
public Result(){ v%PWr5]
super(); ^zluO
} N=?kEX
O
Xe^=(| M
/** x2IU PM
* The constructor using fields JI#Enh!Lv
* @W5hrei
* @param page a^)4q\E
* @param content r
:MaAT<
*/ @xM!:
public Result(Page page, List content){ x)qHeS
this.page = page; \5pAG
mgD
this.content = content; iJj?~\zp
} ~9>[ U%D
;g)Fhdy!
/** ~[/c'3+4qn
* @return Returns the content. =K<I)2
*/ uB%^2{uU
publicList getContent(){ c+K=pp@
return content; uJ5%JB("E
} UFY~D"%/
ZK_@.O+ ]
/** =&g}Y
* @return Returns the page. aD3F!Sn
*/ ] GPz>k
public Page getPage(){ DP'Dg /D
return page;
{{)[Ap)
}
*/dsMa
`]I5WTt*X
/** 3usA
* @param content CR PE?CRQF
* The content to set. KJ{F,fr+v
*/ ^3@a0J=F
public void setContent(List content){ ~ z&A
this.content = content; e8uIh[+ 0
} Z.OrHg1
%-p{?=:K
/** I)/7M}t`
* @param page $m0x8<7nu
* The page to set. =4\~M"[p
*/ ,(kXF:
publicvoid setPage(Page page){ {-]HYk
this.page = page; ='||BxB
} A VG`r2T
} v.&*z48
NHVx!Kc
*RE-K36m|u
|[7$) $
F?AfB[PM
2. 编写业务逻辑接口,并实现它(UserManager, l7y`$8Co
+=04X F:
UserManagerImpl) 6@*;Wk~
java代码: Hh=::Bi
~W2&z]xD
>{)#|pWU
/*Created on 2005-7-15*/ Z/UVKJm>:
package com.adt.service; |a:VpM
){|Lh(
import net.sf.hibernate.HibernateException; UNLNY,P/!)
N}<U[nh'
import org.flyware.util.page.Page; tZ24}~da
KK3xz*W0
import com.adt.bo.Result; T@.m^|~
t>u9NZt G
/** z"C(#Y56 x
* @author Joa 72.IhBNtT
*/ DH*|>m&
publicinterface UserManager { x9
L\"
. pEeR
public Result listUser(Page page)throws g;Q^_4@
_llaH
HibernateException; 0$Db@
1gK3=Ys
} L"<Eov6
0c6AQP"=V
-t#a*?"$w
}ucg!i3C
`%I{l
java代码: ##ea-"m8
t|"d#5'
;9\0x
/*Created on 2005-7-15*/ Z`KXXlJ^i
package com.adt.service.impl; m:<3d]L
p<['FRf"
import java.util.List; !+ hgKZ]
{!bJ.O
l
import net.sf.hibernate.HibernateException; ~7lvY+k)<
<?}g[]i
import org.flyware.util.page.Page; qf$|z`c
import org.flyware.util.page.PageUtil; 2n:J7PGD
'MlC
1HEp
import com.adt.bo.Result; Zpd>' ${4
import com.adt.dao.UserDAO; KTJ$#1q
import com.adt.exception.ObjectNotFoundException; Q*{
2
import com.adt.service.UserManager; V]cY+4Y
1OeDWEcB
/** ~m&oa@*=y
* @author Joa u<2sb;a
*/ <4bo7XH
publicclass UserManagerImpl implements UserManager { .]l2)OlLQ
)BrqE uX@"
private UserDAO userDAO; Gnq~1p5^
2b` M(QL
/** j2n@8sCSO
* @param userDAO The userDAO to set. ]}c=U@D,9
*/ . M$D
publicvoid setUserDAO(UserDAO userDAO){ z:7F5!Z
this.userDAO = userDAO; ?bA]U:
} +'4 dP#
d0,F'?.0|
/* (non-Javadoc) j"=jK^
* @see com.adt.service.UserManager#listUser m,q<R1
dK$dQR#
(org.flyware.util.page.Page)
kS9
*/ oABPGyv
public Result listUser(Page page)throws o`Brr:
#=3]bg
HibernateException, ObjectNotFoundException { 7[ji,.7
int totalRecords = userDAO.getUserCount(); xq*yZ5:5Jo
if(totalRecords == 0) =Bx~'RYl1d
throw new ObjectNotFoundException !g:UM R
7!)%%K.z6
("userNotExist"); 9>P(eN
page = PageUtil.createPage(page, totalRecords); Z%Kj^
M
List users = userDAO.getUserByPage(page); 8r,%! 70
returnnew Result(page, users); y~ LVK8
} y>PbYjuIU
go5!zSs
} Jz b".A
AV!
cCQ
Inoou'jX
+y(h/NcQ
e/Y+S;a
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 x{5*%}lX8
i i
Y[
询,接下来编写UserDAO的代码: Yw
`VL)v(y
3. UserDAO 和 UserDAOImpl: $sJfxh
r
java代码: z<*]h^!3
'M/&bu r
"TI?
qoz
/*Created on 2005-7-15*/ WRM}gWv*
package com.adt.dao; A/aQpEb%
t]XJq
import java.util.List; UkKpSL}Q2
^f]pK&MAmN
import org.flyware.util.page.Page; WLb7]rCTp
u>#'Y+7
import net.sf.hibernate.HibernateException; N"y4#W(Z@
MG>;|*$%
/** ,//=yW
* @author Joa X=~QE}x
*/ wl9icrR>
publicinterface UserDAO extends BaseDAO { "Xc=<rX
Bw[V K7
publicList getUserByName(String name)throws @RW%EXKt
5 <poN)"
HibernateException; !vw0Y,F&
{\I\4P
publicint getUserCount()throws HibernateException; `Fr$q1qae{
`!N?#N:b)
publicList getUserByPage(Page page)throws zZ-*/THB@R
n9 DFa3
HibernateException; -`&;3
7
iYkNtqn/
} dZZ/(oE>
vD t?N9
gw:BKR'o
u)-l+U.
5N0H^
java代码: g>f394j
$-73}[UA 4
;p8xL)mUP
/*Created on 2005-7-15*/ .rHO7c,P~
package com.adt.dao.impl; >{Djx
>E3OYa?G
import java.util.List; Sb.;$Be5g
VXp
X#O
import org.flyware.util.page.Page; *d 4D9(
mDUS9>
import net.sf.hibernate.HibernateException; bql6Z1l
import net.sf.hibernate.Query; {;r5]wimb
C4,W[L]4"
import com.adt.dao.UserDAO; PH.v3
3K
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/** f{0PLFj
* @author Joa [PT}!X7h
*/ |>)mYLN!y
public class UserDAOImpl extends BaseDAOHibernateImpl gC.T5,tn
GU`2I/R
implements UserDAO { Zh*I0m
w'C(? ?mH
/* (non-Javadoc) ifUgj8i_
* @see com.adt.dao.UserDAO#getUserByName gC_U7a w
PQ" Dl=,
(java.lang.String) h.NA$E?7
*/ `fXcW)
publicList getUserByName(String name)throws rE
8-MB
O#g31?TO
HibernateException { ~Q5HM
String querySentence = "FROM user in class Wp $\>
n7vi@^lf(
com.adt.po.User WHERE user.name=:name"; hdzaU&w
Query query = getSession().createQuery p6p_B
h1$,
(querySentence); PYGHN
T
query.setParameter("name", name); *P>F#
~X
return query.list(); ~7|z 2L
} ^<c?I re
wbTw\b=
/* (non-Javadoc) <#sK~G
* @see com.adt.dao.UserDAO#getUserCount() *" wsMO
*/ NeH^g0Q2,g
publicint getUserCount()throws HibernateException { Jc*A\-qC.
int count = 0; LvS`
String querySentence = "SELECT count(*) FROM t$b`Am
S:wmm}XQ
user in class com.adt.po.User"; q-'zZ#
Query query = getSession().createQuery 8l6R.l
j1)w1WY0@
(querySentence); :7gIm|2"]
count = ((Integer)query.iterate().next @L0.Z1 ).
sqhM[u
k
()).intValue(); ^+88z>
return count; +m_quQ/ys
} $|AxQQ%f
eG.?s;J0
/* (non-Javadoc) pV_2JXM~@
* @see com.adt.dao.UserDAO#getUserByPage "b qB@)
bTJ7RqL
(org.flyware.util.page.Page) z@ 2NAC
*/ nL9m{$Zv
publicList getUserByPage(Page page)throws o}BaZ|iZ2
OvkY zI`
HibernateException { k#
/_Zd
String querySentence = "FROM user in class kjH0u$n
z?7pn}-
com.adt.po.User"; Lq:Z='Kc
Query query = getSession().createQuery BO^e.iB/
cOcm9m#
(querySentence); 5=eGiF;0\
query.setFirstResult(page.getBeginIndex()) Q/':<QY
.setMaxResults(page.getEveryPage()); :EZTJu
return query.list(); i9Qx{f88
} W1 E((2
AyddkjX
} :%R3(
&
E8/P D
7C=t19&R'
(sY?"(~j?T
1r$q $\
至此,一个完整的分页程序完成。前台的只需要调用
W<t,Ivg
_("{fJ,A
userManager.listUser(page)即可得到一个Page对象和结果集对象 o`G@Je_}x
1Ypru<.)W
的综合体,而传入的参数page对象则可以由前台传入,如果用 rQU;?[y
UPH:$Fk&
webwork,甚至可以直接在配置文件中指定。 n<MH\.!tM
RX'(
l
下面给出一个webwork调用示例: h/d&P
java代码: uCx\Bt"VI
o}<}zTU
S>nM&758
/*Created on 2005-6-17*/ -YD6
package com.adt.action.user; VK8 5A
QM
O OJA
import java.util.List; p tMysYT'
tR1
kn&w
import org.apache.commons.logging.Log; N]gdS]pP2{
import org.apache.commons.logging.LogFactory; .pZwhb
import org.flyware.util.page.Page; :*1bhk8~
fn)c&|aCt
import com.adt.bo.Result; ^8DC
W`V
import com.adt.service.UserService; qjuX16o
import com.opensymphony.xwork.Action; F9N)UW:w
M%Ov6u<I8
/** |+%K89W
* @author Joa 0]&~ddL
*/ $w{#o E
publicclass ListUser implementsAction{ uk16
W,:*`
privatestaticfinal Log logger = LogFactory.getLog |dK_^~;o
UW!!!
(ListUser.class); ,JX/`7y
ygh*oVHO
private UserService userService; M(xd:Fa?
;a2TONW
private Page page; XDU&Z2A
{2A/ @$?
privateList users; lj(}{O
KnKV+:"
/* y8VLFe;
* (non-Javadoc) "YM)bc
* wUab)L
* @see com.opensymphony.xwork.Action#execute() ;kY'DKL(
*/ !>+YEZ"
publicString execute()throwsException{ b k 30d
Result result = userService.listUser(page); 3DbS\jja
page = result.getPage(); S
7RB`I5
users = result.getContent(); .>_p7=a
return SUCCESS; ?Jio9Zr
} __OD^?qa
WOiw 0
/** "9aiin
* @return Returns the page. a~=$9+?w
*/ 1d,;e:=j
public Page getPage(){
hT]\*},
return page; X0O@,
} YLk/16r
WbB0{s
/** lOYzo
* @return Returns the users. "CX&2Xfe
*/ *%bQ p
publicList getUsers(){ A70x+mjy^T
return users; =y.? =`"
} |p}qK
Fdi
/z9oPIJ=*
/** h.(CAm%Y7
* @param page w-LMV>+6|
* The page to set. 2Ck'A0d
*/ bd_&=VLTC
publicvoid setPage(Page page){ 0j@gC0xu)|
this.page = page; <KlG#7M>
} eX;C.[&7;8
.-Yhpw>f
/** Ksr.'
* @param users ;rC)*=4#
* The users to set. NBU[> P
*/ \$Lr L
publicvoid setUsers(List users){ 80DcM9^t8
this.users = users; S2T~7-
} ;Sl]8IZ
[oqb@J2
/** Fg;V6s/>ts
* @param userService FwKT_XkY
* The userService to set. 6qp2C]9=
*/ VPBlU
publicvoid setUserService(UserService userService){ D',[M)
this.userService = userService; s~V%eq("}
} 9M8n
} _\uyS',
.s Ci9d
WR
V/"P};n
ancs
ruiAEC<Ej
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, aAJ'0xnj
FtHR.S=u
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 g?-HAk6
T$)N2]FE
么只需要: 9[31EiT
java代码: F-0 |&0
T-S6`^_L
2GkJ7cL
<?xml version="1.0"?> C^2J<
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork w% Vw*i6o
A"ApWJ3
1.0//EN" "http://www.opensymphony.com/xwork/xwork- &b~if}vcb
]w*w@:Zk
1.0.dtd"> {\u=m>2U|
D}YAu,<K
<xwork> d'y\~M9(
KicPW}_
<package name="user" extends="webwork- 9b88):[qO
BTi:Bcv k
interceptors"> vOMmsU F
EdgcdSb7
<!-- The default interceptor stack name lyZ[tP S
! 3&_#VO
--> afE`GG-
<default-interceptor-ref *|97 g*G(
fjGYp
name="myDefaultWebStack"/> J)yNp,V
ii,/omn:
<action name="listUser" (?[^##03MN
E6
glR
class="com.adt.action.user.ListUser"> \l$gcFXb
<param x.J%
c[Q8
k(As^'>
name="page.everyPage">10</param> 1"7Rs}l7
<result e&*< "WN
U TT 7a"
name="success">/user/user_list.jsp</result> q4Z9;^S
</action> e;_ cC7
CB&$tDi
</package> e[`u:
Qqju6} +
</xwork> P01o: /}
{-FS+D`
^dc~hD
YTWlR]Tr6?
~x}/>-d
>'\cNM~nf
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 mI;#Zq_j
WcE{1&PXx
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。 L!fiW`>0G
*p&c}2'
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 8Df(|>mK
WrzyBG_
i]sz*\P~
8+gti*C?\
%x Xib9J
我写的一个用于分页的类,用了泛型了,hoho io8c[#"uU
f[}N
java代码: n4* hQi+d
Av3qoH)[<
?=C?3R
package com.intokr.util; <[N"W82p
w"p,6Ew
import java.util.List; e@B+\1
\=kre+g
/** 7x,c)QES`
* 用于分页的类<br> 67916
* 可以用于传递查询的结果也可以用于传送查询的参数<br> z@\r V@W5
* ~KtA0BtC
* @version 0.01 [5KzawV
* @author cheng HkH!B.H]
*/ ^Md]e<WAp
public class Paginator<E> { k{fTqKS%h
privateint count = 0; // 总记录数 mn5"kYy?
privateint p = 1; // 页编号 M@LI(;
privateint num = 20; // 每页的记录数 !kzC1U
privateList<E> results = null; // 结果 86.LkwlqoH
)@%wj;>a
/** OIT9.c0h
* 结果总数 W6=j^nv
*/ QEUr+7[
publicint getCount(){ oN0p$/La
return count; W`$D*X0*o
} eh@6trzp=
}=d]ke9_
publicvoid setCount(int count){ ubq4Zv7'
this.count = count; %j
'_I\
} $-Ud&sjn
jQrj3b.NC3
/** ^\Bm5QkS
* 本结果所在的页码,从1开始 ?zypF 5a
* 5P?7xRA
* @return Returns the pageNo. Sk*-B@!S
*/ .*9+%FN
publicint getP(){ `vkNp8|
return p; aFZu5-=x
} )+'De
c^N'g!on
/** }]8n3&*
* if(p<=0) p=1 2!6+>nvO
* HkGA$
* @param p H,/|pP.
*/ dMcCSwYh
publicvoid setP(int p){ bzI!;P1&
if(p <= 0) 95`Q=I|i
p = 1; 3 #fOrNU2
this.p = p; ]Bpdb'
} QQQ3U
|2!!>1k
/** XxN=vL&m
* 每页记录数量 i\4Q v"%
*/ ||{V*"+\
publicint getNum(){ 5IK -V)
return num; uVO*@Kj+
} 3$]SP1Mc(
1x\Vz\
/** 3ug|H
* if(num<1) num=1 W%/lBkP
*/ fxW,S
publicvoid setNum(int num){ 50 s)5G#
if(num < 1) r6B\yH2
num = 1; F4!,8)}
this.num = num; WK{{U$:$
} {l /]+8G^
<NIg`B@ 's
/** /7EeM{,~
* 获得总页数 o6H\JCne
*/ c5>'1 L
publicint getPageNum(){ ]6W;~w%
return(count - 1) / num + 1; F vJJpPS
} (}$~)f#s
6mawcK:7
/** |FF"vRi8a7
* 获得本页的开始编号,为 (p-1)*num+1 l7rGz2:?
*/ ~2R3MF.C
publicint getStart(){ %]>LnbM>4
return(p - 1) * num + 1; 2TR l@
} UV ?.KVD~
FTB@70
/** hq5=>p
* @return Returns the results. Ol;}+?[Q
*/ ZI<p%IQ
publicList<E> getResults(){ W*'gqwM&
return results; Jk$XL<t
} <Pg]V:=g'
\ 2Jr(?U
public void setResults(List<E> results){ (h"Yw
this.results = results; v-*CE[
} EYwDv4H,g
\u|8MEB
public String toString(){ i- Le&
StringBuilder buff = new StringBuilder 0(owFNUBs
#3:;&@#
(); ] Q}z-U
buff.append("{"); |( %3'"Z
buff.append("count:").append(count); wH:'5+u:6
buff.append(",p:").append(p); 2>s@2=Aq
buff.append(",nump:").append(num); YNGG> ;L
buff.append(",results:").append Sa V]6/|
>s@6rNgf
(results); Cm4$&?
buff.append("}"); X%S9H^9
return buff.toString(); NXAP=y3
} .3(=UQ
>E;&SX
} =y3gnb6
w|6;Pf~1y)
jGB2`^&d