Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 zG' "9kJx
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3uZJ.Fb
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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 YLwnhy>dD
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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 CbPuoOl
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。 qOSg!aft{Q
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分页支持类: 4l!@=qwn
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java代码: aFe`_cnG
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package com.javaeye.common.util; [q_`X~3
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import java.util.List; neXeAU
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publicclass PaginationSupport { masT>vM
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publicfinalstaticint PAGESIZE = 30; is1' s[
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privateint pageSize = PAGESIZE; |\n@3cIK
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privateList items; ] GHt"
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privateint totalCount; 1G0fp:\w
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privateint[] indexes = newint[0]; /,MJq#@K
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privateint startIndex = 0; %&->%U|'
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public PaginationSupport(List items, int {&P
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totalCount){ 26dUA~|KJ
setPageSize(PAGESIZE); P+!"wX0*N
setTotalCount(totalCount); L4b:F0
setItems(items); n:0}utU4
setStartIndex(0); bn(`O1r[(
} JXixYwm
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public PaginationSupport(List items, int kdxz !
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totalCount, int startIndex){ A%Xt|=^_
setPageSize(PAGESIZE); Yz4_vePh+5
setTotalCount(totalCount); N%7{J
setItems(items); m6MOW&
setStartIndex(startIndex); V~T@6S
} !" JfOu
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public PaginationSupport(List items, int Ja]?&j
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totalCount, int pageSize, int startIndex){ kW`r= u
setPageSize(pageSize); OFGsjYLw
setTotalCount(totalCount); 6
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setItems(items); Q|,B*b
setStartIndex(startIndex); K*IxUz(
} zOHypazOTq
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publicList getItems(){ /Y&02L%\3s
return items; *d(SI<j
} @v}B6j b;
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publicvoid setItems(List items){ )jCo%P/
this.items = items; d'*]ns
} =(EI~N
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publicint getPageSize(){ aYn8^
return pageSize; hKNY+S})g
} ~"lJ'&J}
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publicvoid setPageSize(int pageSize){ WKpA|
this.pageSize = pageSize; !mRx$
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} &3v&i*DG,I
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publicint getTotalCount(){ uNHdpni
return totalCount; - ZW3
} .c^
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publicvoid setTotalCount(int totalCount){ vBvNu<v7te
if(totalCount > 0){ [EY`am8[
this.totalCount = totalCount; oyk>vIZ
int count = totalCount / n;8 '`s
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pageSize; wQ+dJ3b$
if(totalCount % pageSize > 0) U{~SXk'2+
count++; /ahNnCtu?1
indexes = newint[count]; Z~6[ Z
for(int i = 0; i < count; i++){ o<l 2 r
indexes = pageSize * 3Db3xN
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i; B/J&l
} b@t5`Y-+K
}else{ IN7<@OS7
this.totalCount = 0; xU
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} (X +s-4%
} ?/M_~e.P
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publicint[] getIndexes(){ #FYAV%pi
return indexes; L{ho*^b
} ?$z.K>S5
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publicvoid setIndexes(int[] indexes){ S2C]?6cTq
this.indexes = indexes; p T[gdhc
} "PH6e bm
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publicint getStartIndex(){ s?3i)Ymr
return startIndex; 4ZC!SgJo
} td{O}\s7D
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publicvoid setStartIndex(int startIndex){ `C_'|d<HA
if(totalCount <= 0) b-@\R\T
this.startIndex = 0; 7S$&S;
elseif(startIndex >= totalCount) PT9v*3Bq~
this.startIndex = indexes R4e&^tI@*
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[indexes.length - 1]; DF1<JdO+
elseif(startIndex < 0) LS.r%:$mb
this.startIndex = 0; K(T\9J.
else{ 'GJVWpvUU
this.startIndex = indexes M R'o{?{e`
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[startIndex / pageSize]; *~z#.63oZ
} DB`QsiC)
} zzZg$9PT[
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publicint getNextIndex(){ wk\L* \@Y}
int nextIndex = getStartIndex() + %do1i W
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pageSize; \k.vN@K#
if(nextIndex >= totalCount) ~ eN8|SR
return getStartIndex(); b
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else ~!+ _[uJ
return nextIndex; cs_}&!c{
} Zv qn%K],
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publicint getPreviousIndex(){ -NM0LTF
int previousIndex = getStartIndex() - hPdx(E)8!d
80ZnM%/}
pageSize; ^m7~:=K7WG
if(previousIndex < 0) 3+YbA)i;
return0; h ?#@~
else jB@4b'y
return previousIndex; !rTmR@e$/
} (:\LWJX0=
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} (U87}}/l
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抽象业务类 ;?IT)sNY
java代码: `Y3( ~~YGn
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/** 3vJ12=
* Created on 2005-7-12 d*;$AYI#R
*/ fk5XvL
package com.javaeye.common.business; A%ywj'|z
*,#q'!Hq
import java.io.Serializable; I ftxSaP
import java.util.List; 0^_MN~s(X
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import org.hibernate.Criteria; K5 vNhA
import org.hibernate.HibernateException; ]1fZupM^6
import org.hibernate.Session; "D> ]ES%5
import org.hibernate.criterion.DetachedCriteria; ValS8V*N1
import org.hibernate.criterion.Projections; pbB2wt
import \~"#ld(x7
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org.springframework.orm.hibernate3.HibernateCallback; rm+v(&
import 85>S"%_
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org.springframework.orm.hibernate3.support.HibernateDaoS B.-A $/
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upport; c %<2z
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import com.javaeye.common.util.PaginationSupport; (iDBhC;/B
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public abstract class AbstractManager extends z g]Drm
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HibernateDaoSupport { 4DM L
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privateboolean cacheQueries = false; ^eTZn[qH>w
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privateString queryCacheRegion; QTh0SL
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publicvoid setCacheQueries(boolean aR(E7mXQ
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cacheQueries){ f4]&pcK
this.cacheQueries = cacheQueries; U6i~A9;
} +G!v!(Ob+
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publicvoid setQueryCacheRegion(String J'7 y
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queryCacheRegion){ q0|ZoP
this.queryCacheRegion = z<QIuq
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queryCacheRegion; E*4t8
} /Nqrvy=
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publicvoid save(finalObject entity){ ??TdrTS
getHibernateTemplate().save(entity); </w7W3F
} y''0PSfb#
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publicvoid persist(finalObject entity){ X\G)81Q.S
getHibernateTemplate().save(entity); wF;B@
} U(A4v0T
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publicvoid update(finalObject entity){ LD@7(?mlU
getHibernateTemplate().update(entity); 7ti<
} ;l`X!3
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publicvoid delete(finalObject entity){ -RCv7U`
getHibernateTemplate().delete(entity); !d|8'^gc
} x[}06k'
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publicObject load(finalClass entity, *K!7R2Rat
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finalSerializable id){ (+$ol'i
return getHibernateTemplate().load \6c8z/O7
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(entity, id); US]"4=Zm
} KQW!\y?$"
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publicObject get(finalClass entity, hOSf'mi
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finalSerializable id){ toN
return getHibernateTemplate().get 4 f3=`[%
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(entity, id); u
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} wjg}[R@!
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publicList findAll(finalClass entity){ y$v@wb5
return getHibernateTemplate().find("from 2:/u2K
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" + entity.getName()); oEPNN'~3
} G/%Ubi6%
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publicList findByNamedQuery(finalString I-,X wj-
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namedQuery){ [M<{P5q
return getHibernateTemplate (-#rFO5~l
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().findByNamedQuery(namedQuery); Cl-S=q@>V
} tbRE/L<
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publicList findByNamedQuery(finalString query, eTT^KqE>&
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finalObject parameter){ XzN-slu!
return getHibernateTemplate 6HB]T)n
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().findByNamedQuery(query, parameter); xan/ay>
} &,_?>.\[<
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publicList findByNamedQuery(finalString query, hQP6@KIe)
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finalObject[] parameters){ `6n!$Cxo
return getHibernateTemplate D@}St:m}
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().findByNamedQuery(query, parameters); Iy6p>z|
} i)GeX:
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publicList find(finalString query){ vx PDC~3;
return getHibernateTemplate().find #?A]v>I;C
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(query); /bu'6/!`
} KuU3DTS85Z
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publicList find(finalString query, finalObject !k%l+I3J[
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parameter){ kf}F}Ad:%
return getHibernateTemplate().find A>J1B(up
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(query, parameter); [}jj<!9A_;
} @'@s*9Nr
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public PaginationSupport findPageByCriteria y @]8Ep
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(final DetachedCriteria detachedCriteria){ $hyqYp"/;
return findPageByCriteria uT'-B7N
#:
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); C,9)V5!tP2
} B#| Z`mZ
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public PaginationSupport findPageByCriteria $^!a`Xr
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(final DetachedCriteria detachedCriteria, finalint uDpf2(>s
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startIndex){ RI#lI~&)
return findPageByCriteria }g%KvYB_
_ .-o%6
(detachedCriteria, PaginationSupport.PAGESIZE, u-8X$aJ
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startIndex); y|FBYcn#F
} v@F|O8t:s
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public PaginationSupport findPageByCriteria %kFTnXHK
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(final DetachedCriteria detachedCriteria, finalint HGU?bJ~6o
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pageSize, bbfDt^
finalint startIndex){ N |OMj %Uk
return(PaginationSupport) 7KvXTrN!9
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getHibernateTemplate().execute(new HibernateCallback(){ -d$8WSI8
publicObject doInHibernate iSSc5ek4
e{^:/WcYB
(Session session)throws HibernateException { P-/XYZ]`
Criteria criteria = Z?!JV_K
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detachedCriteria.getExecutableCriteria(session); K> c8r8!
int totalCount = Z/XM`Cy
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((Integer) criteria.setProjection(Projections.rowCount ccHLL6F{
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()).uniqueResult()).intValue(); ?Zc/upd:$N
criteria.setProjection
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(null); $[HcHnf
List items = p?J~'
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criteria.setFirstResult(startIndex).setMaxResults v>x {jZkFL
lM@<_=2
(pageSize).list(); G\'u~B/w
PaginationSupport ps = : ;E7+m
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new PaginationSupport(items, totalCount, pageSize, KdBq@
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startIndex); M<SbVP|V"
return ps; 8`L#1ybMO
} t
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}, true); U}A|]vi@
} u7<qaOzs?
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public List findAllByCriteria(final *G2)@0
{
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DetachedCriteria detachedCriteria){ BR&Qw'O%
return(List) getHibernateTemplate fD3jwPL
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().execute(new HibernateCallback(){ *zw
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publicObject doInHibernate cJ7{4YK_#/
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(Session session)throws HibernateException { VuX>
Criteria criteria = pJ2:` f<;
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detachedCriteria.getExecutableCriteria(session); cuV8#:
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return criteria.list(); .-O@UQx.I
} 8%vh6$s6/
}, true); i-:8TfI,
} L&!g33J&
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public int getCountByCriteria(final t+W=2w&
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DetachedCriteria detachedCriteria){ S:2u3th7
Integer count = (Integer) `uM0,Z
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getHibernateTemplate().execute(new HibernateCallback(){ KG4#BY&^
publicObject doInHibernate CN8@c!mB
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(Session session)throws HibernateException { oUKBb&&O
Criteria criteria = ^hl]s?"3
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detachedCriteria.getExecutableCriteria(session);
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return cKi^C
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criteria.setProjection(Projections.rowCount (^s &M
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()).uniqueResult(); epGX.
} zDvP7hl
}, true); 7T|J[WO
return count.intValue(); 'o)ve(
} /IrR,bvA
} 8XS{6<
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用户在web层构造查询条件detachedCriteria,和可选的 /]MB6E7&
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 #iRyjD
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PaginationSupport的实例ps。 c:@OX[##
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ps.getItems()得到已分页好的结果集 cAKoPU>U
ps.getIndexes()得到分页索引的数组 w
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ps.getTotalCount()得到总结果数 JK:mQ_
ps.getStartIndex()当前分页索引 mNnw G);$
ps.getNextIndex()下一页索引 \AtwO
ps.getPreviousIndex()上一页索引 Kl46CZs#8
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}!Diai*C
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 aaf_3UH.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 eUKl
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一下代码重构了。 OFQi&/
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我把原本我的做法也提供出来供大家讨论吧: 4xAlaOw5M
TOPPa?=vk
首先,为了实现分页查询,我封装了一个Page类: F~Z 0
java代码: [K)1!KK,L
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/*Created on 2005-4-14*/ &x0TnW"g
package org.flyware.util.page; ?CT^Zegmr
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/** Zs5I?R1e8
* @author Joa "$E!_
* yd2qf
*/ |`(?<m
publicclass Page {
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/** imply if the page has previous page */ -o!,,XYj .
privateboolean hasPrePage; ]}l+ !NV<
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/** imply if the page has next page */ ,m?UFRi
privateboolean hasNextPage; ?_Dnfa_
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/** the number of every page */ 'MdE}
privateint everyPage; I_6` Z 0
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/** the total page number */ /o1)ZC$
privateint totalPage; iq^L~RW5e
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/** the number of current page */ 18/@:u{
privateint currentPage; MMA@J
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/** the begin index of the records by the current =<'iLQb1
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query */ F;X q:e8
privateint beginIndex; xXU/m|
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/** The default constructor */ B]KLn?zt5
public Page(){ eRx[&-c
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} J,=E5T}U^
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/** construct the page by everyPage ='bmjXu
* @param everyPage k+R?JWC:
* */ yxP ?O@(
public Page(int everyPage){ BL5
this.everyPage = everyPage; 5WNg+
} vBn=bb'W
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/** The whole constructor */ 8rG&CxI
public Page(boolean hasPrePage, boolean hasNextPage, ?jn6Op
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W &wDH
int everyPage, int totalPage, 7}1Kafs
int currentPage, int beginIndex){ +heS\I_Mp
this.hasPrePage = hasPrePage; ])wMUJWg2
this.hasNextPage = hasNextPage; /qq&'}TZP
this.everyPage = everyPage; :XQ
this.totalPage = totalPage; 'lRHdD}s
this.currentPage = currentPage; _TN$c
this.beginIndex = beginIndex; &|{,4V0%A
} c+)|o!d
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/** z3jzpmz
* @return 6-X?uaY)os
* Returns the beginIndex. hYZ:" x
*/ :kx#];2i
publicint getBeginIndex(){ 4b(irDT3F
return beginIndex; Mjvso0zj
} iCSM1W3
YTPmS\ H _
/** B*iz+"H
* @param beginIndex Isgk
* The beginIndex to set. *pC-`k
*/ Q|<?$.FN"8
publicvoid setBeginIndex(int beginIndex){ F Hcqu_;J
this.beginIndex = beginIndex; .x$T al
} ~m|?! ]n
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/** QRHm|f9_C
* @return 2[YD&
* Returns the currentPage. taEMr> /
*/ f>+}U;)EF
publicint getCurrentPage(){ wG?kcfu
return currentPage; geN%rD
} ;_\
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/** 5)v^
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* @param currentPage gwz _b
* The currentPage to set. P"~T*Qq-R
*/ FC(cXPX}
publicvoid setCurrentPage(int currentPage){ 'C>S yU
this.currentPage = currentPage; i8) :0
}
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/** 0S7Isk2W
* @return +,^M{^%
* Returns the everyPage. :*+BBC
*/ .F3LA6se
publicint getEveryPage(){ %1 ^jd\
return everyPage; m.a1
} 5a_!&
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/** JI,hy
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* @param everyPage ![!b^:f
* The everyPage to set. *g41"Cl
*/ 5XUI7Q%
publicvoid setEveryPage(int everyPage){ =l'_*B8
this.everyPage = everyPage; 6ch[B`[h,
} QIV~)`;
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/** i@^`~vj
* @return <0
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* Returns the hasNextPage. 1sLfjH hv
*/ ']Xx#U N
publicboolean getHasNextPage(){ RcM0VbR"EU
return hasNextPage; vm^# aoDB
} "K!BJQ
.mrRv8>$
/** "wC5hj]
* @param hasNextPage f4I9H0d;!
* The hasNextPage to set. OYp8r
*/ fDHISJv
publicvoid setHasNextPage(boolean hasNextPage){ wSyu^KDz
this.hasNextPage = hasNextPage; qTMz6D!Q
} ujqktrhuLb
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/** BvR3Oi@Wc
* @return ~2}ICU5
* Returns the hasPrePage. [:S F(*}
*/ ^ED>{UiNI
publicboolean getHasPrePage(){ Df3v"iCq}
return hasPrePage; F X2`p_
} ;l?(VqX_E
=F[,-B~
/** ^ 6|"=+cO\
* @param hasPrePage \)uad5`N
* The hasPrePage to set. 13kb~'+&r
*/ z))[Lg
publicvoid setHasPrePage(boolean hasPrePage){ 7uNI
this.hasPrePage = hasPrePage; be#"517
} ^!Jm/-
N,Bs% p#1
/** qM !q,Q
* @return Returns the totalPage. U7eQ-r
* G.e\#_RR?
*/ .Awq(
publicint getTotalPage(){ B8Zd#.6]
return totalPage; *bSG48W("
} ~At.V+
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/** Li^!OHro.
* @param totalPage c6)zx
b
* The totalPage to set. kxwm08/|f
*/ 97dI4t<
publicvoid setTotalPage(int totalPage){ YDD]n*&
this.totalPage = totalPage; 'B6H/d>
} bQjHQ"G
3*JybMo"
} >G~;2K[
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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 w! 7/;VJ3d
dS=,. }
个PageUtil,负责对Page对象进行构造: |c/rHEZ
java代码:
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/*Created on 2005-4-14*/ R7E"7"M10
package org.flyware.util.page; RR=l&uT
%BLKB%5
import org.apache.commons.logging.Log; !{lb#
import org.apache.commons.logging.LogFactory; lGhUfhk
V%=t2+
/** K$]B"
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* @author Joa
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* { rn~D5R
*/ 3R.cj
publicclass PageUtil { fBOG#-a}
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privatestaticfinal Log logger = LogFactory.getLog {HnOUc\4
.r'.5RI A
(PageUtil.class); \0*LfVr;P
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/** c'R|Wyf
* Use the origin page to create a new page v4aGL<SO
* @param page M6!brj\[|
* @param totalRecords 7^=jv~>wP
* @return ,u2<()`8D
*/ Su #1yw>
publicstatic Page createPage(Page page, int +-d>Sl (
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totalRecords){ T]2q >N
return createPage(page.getEveryPage(), heA\6W:u&
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page.getCurrentPage(), totalRecords); a!]%@A6p
} 7yl'!uz)9
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/** "O
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* the basic page utils not including exception 0in6z
/]&1 XT?
handler Yl])Q|2I
* @param everyPage Lp=B? H
* @param currentPage Q pq0j^\
* @param totalRecords W0kq>s4
* @return page 8<!9mgh
*/ @oNrR$7
publicstatic Page createPage(int everyPage, int oZtz"B
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currentPage, int totalRecords){ qW^l2Jff
everyPage = getEveryPage(everyPage); hd-ds~ve
currentPage = getCurrentPage(currentPage); 6I0MJpLW
int beginIndex = getBeginIndex(everyPage, g*M3;G
O~VUViS6$
currentPage); % BKTN@;7
int totalPage = getTotalPage(everyPage, >w2u
-bF+uCfba
totalRecords); *
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boolean hasNextPage = hasNextPage(currentPage, +
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6:pN?|=6X
totalPage); Y~!@
boolean hasPrePage = hasPrePage(currentPage); v%^H9aK_
`( Gk_VAa
returnnew Page(hasPrePage, hasNextPage, yK^k*)2N
everyPage, totalPage, z16++LKmM
currentPage, sx\7Z#|
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beginIndex); tEj5WEnNE8
} <n{9pZ5.
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privatestaticint getEveryPage(int everyPage){ XjbK!.
return everyPage == 0 ? 10 : everyPage; _guY%2%yR
} (k~c]N)v
v*LL7b0A
privatestaticint getCurrentPage(int currentPage){ Kw|`y %~
return currentPage == 0 ? 1 : currentPage; ZlzFmNe60
} dmO|PswW
:JYOC+#q7
privatestaticint getBeginIndex(int everyPage, int ] W_T(C*
OHw6#N$\
currentPage){ 9'M_t Mm5
return(currentPage - 1) * everyPage; d?n~9_9e
} L z
VbYapPu4b!
privatestaticint getTotalPage(int everyPage, int _?"J.i
(
9l|^w["
totalRecords){ K]l)z* I
int totalPage = 0; plq\D.C
14R))Dz"
if(totalRecords % everyPage == 0) r[~$
totalPage = totalRecords / everyPage; .B*)A.
else zl5S)/A
totalPage = totalRecords / everyPage + 1 ; 3^Y-P8.zdB
"oQ@.]-#
return totalPage; ZSNg^)cN
} Z"jo
xZ
N.?Wev{
privatestaticboolean hasPrePage(int currentPage){ ~nQb;Bdh%
return currentPage == 1 ? false : true; ra1hdf0"
} 7Fp2=j
X)~-MY*p
privatestaticboolean hasNextPage(int currentPage, iu 'yB
XN@5TZoaW
int totalPage){ YAog;QL
return currentPage == totalPage || totalPage == 6FE[snw
tdm /U
0 ? false : true; VbjFQ@[l!
} 1tDN$rM5
Z6p>R;9n
I(.XK ucU
} sAb|]Q((
H;6V
o>YRKb
2-4%h!
oaHBz_pg
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 >7|37a
kL-+V)Kl
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 -Da_#_F
Sv ,_G'
做法如下: *sTQ9 Kr
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]:;gk&P
":Q^/;D}U
的信息,和一个结果集List: <bH>\@p7}
java代码: Z&%61jGK
wa C%o%fD
VYBl0!t
/*Created on 2005-6-13*/ cmTZ))m
package com.adt.bo; 1gC=xMAT
F2&KTK
import java.util.List; E=y#~W
M@8(h=
import org.flyware.util.page.Page; }Y[.h=X
j{vzCRa>8
/** MI/1uw
* @author Joa ]mp.KvB
*/ __QTlj
publicclass Result { y!#1A?|k
Umqm5*P(
private Page page; #ua#$&p
?@nu]~
private List content; *VH1(E`hl
e\89;)
/** Q_dFZ
* The default constructor P|\,kw>l
*/ 1#'wR3[+
public Result(){ Xf0pQ]8\
super(); 4&\m!s
} @*oi1_q
TzOf&cs/r
/** tFGLqR%/
* The constructor using fields "Xm'(c(
* dL"v*3Fy
* @param page ()7=(<x{
* @param content gnv4.f:
*/ olqHa5qn
public Result(Page page, List content){ 0zd1:*KR,
this.page = page; i@2?5U>h
this.content = content; |y]#-T?)t
} .Ee8s]h5W
%>f:m!.
/** .JzO f[g5
* @return Returns the content.
np~oF
*/ %spR7J\"/
publicList getContent(){ /XXW4_>
return content; th]9@7UE,
} xkX,
l{6
htjJ0>&
/** |h#mv~cF
* @return Returns the page. 'K0Y@y
*/ 4U((dx*m
public Page getPage(){ ?.T=(-
return page; ?D.]c;PR
} 3}H94H)]a
!u^(<.xJ
/** k8h$#@^
* @param content ? 0%lB=qQ
* The content to set. 39OZZaWL
*/ Bp}<H<@
public void setContent(List content){ cD{[rI
E3
this.content = content; r6^DD$X
} 0c]Lm?&
6gp3n;D
/** !_]WUQvV?
* @param page O9opX\9
* The page to set. _h5@3>b3r
*/ 5!AzEB
publicvoid setPage(Page page){ i$ Zhk1
this.page = page; Xdjxt?*
} t?/#:J*_7
} !D1F4v[c=
?^yZVmAo]
2LgRgY{Bl
~oOOCB
yXDf;`J
2. 编写业务逻辑接口,并实现它(UserManager, GE"#.J4z
tn p]wZ
UserManagerImpl) rtY0?
java代码: n&@\[,B
Qd@`jwjS
L%<1cE))
/*Created on 2005-7-15*/ (ttO
O45
package com.adt.service; Chjth"
;X\!*Loe
import net.sf.hibernate.HibernateException; NxNz(R
$~
-tDmzuD6
import org.flyware.util.page.Page; ~_R=2t{u_
|,.glL
import com.adt.bo.Result; {4#'`Eejj
T9u/|OP
/** B=9|g1e
* @author Joa |vzGFfRI
*/ iLFF "Hs
publicinterface UserManager { 5^tL#
+lE 9*Gs_$
public Result listUser(Page page)throws Ua(!:5q?
e\/Lcng
HibernateException; 6tP^_9njy
rNZN}g
} Nn%{Ka
Jln dypE
f4uK_{
K^9!Qp
Vk[m$
java代码: 3EAu#c@q"
`57ffQR9
Dtelr=/s
/*Created on 2005-7-15*/ Nk]r2^.z[
package com.adt.service.impl; [t,7H
W|~Ehg
import java.util.List; U{HJNftdpm
sHKT]^7
import net.sf.hibernate.HibernateException; ca-|G'q
1J^{h5?lU
import org.flyware.util.page.Page; -p9|l%W
import org.flyware.util.page.PageUtil; g,9o'fs`x
J8(v65
import com.adt.bo.Result; l 4(-yWC$H
import com.adt.dao.UserDAO; #Ey!?Z
import com.adt.exception.ObjectNotFoundException; 7j{SCE;
import com.adt.service.UserManager; J}lBKP:-*
Z5\u9E"]
/** Zs)HzOP)9
* @author Joa kyz_r6
*/ 5^[V%4y>
publicclass UserManagerImpl implements UserManager { WG<D+P
y1f&+y9e
private UserDAO userDAO; zZseK
sJ!AI
n<
/** /O+,vRw\A
* @param userDAO The userDAO to set. ^O4.$4t|
*/ 2,'m]`;GNr
publicvoid setUserDAO(UserDAO userDAO){ l3-;z)SgH
this.userDAO = userDAO; k.?b2]@$
} Q+gQ"l,95
`AQv\@wp
/* (non-Javadoc) eZT923tD
* @see com.adt.service.UserManager#listUser +ImPNwrY
u9QvcD^'z
(org.flyware.util.page.Page) #\o
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*/ 3-srt^>w*
public Result listUser(Page page)throws r0}Z&>]66N
E[^66(KR
HibernateException, ObjectNotFoundException { :Q"]W!kCs
int totalRecords = userDAO.getUserCount(); W8R@Pf
if(totalRecords == 0) _G,`s7Q,w
throw new ObjectNotFoundException MHk\y2`/;
3\G&fb|?}R
("userNotExist"); V#=o<
page = PageUtil.createPage(page, totalRecords); ma vc$!y
List users = userDAO.getUserByPage(page); 4Rp2
returnnew Result(page, users); h@t&n@8O?
} u\.7#D>
K6{{\r
} o%5^dX&[
2t*@P"e!
"\U$aaF
o"J}@nF
\XhzaM
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 u.gnvdU
OcwD<Xy
询,接下来编写UserDAO的代码: S~/zBFo-
3. UserDAO 和 UserDAOImpl: 2/x+7F}w5
java代码: ZFY t[:
.{*V^[.
;}ileLTl
/*Created on 2005-7-15*/ O3PE
w4yA
package com.adt.dao; Y }aa6
:"|}oKT%mP
import java.util.List; ci <`*>l
=4 36/O`K
import org.flyware.util.page.Page; sTU`@}}
=6Ihk
import net.sf.hibernate.HibernateException; b7p&EK"Hm
z;x$tO
/** 1nye.i~
* @author Joa &ScADmZP^d
*/ oyiEOC
publicinterface UserDAO extends BaseDAO { MyXgp>?~T
S1.w^Ccy
publicList getUserByName(String name)throws 49E<`f0
wWQv]c%
HibernateException; SoI"a^fY
Kzfa4C
publicint getUserCount()throws HibernateException; )#N)w5DU
CfNHv-jDL
publicList getUserByPage(Page page)throws rfpeX
m(L]R(t
HibernateException; +'Ec)7m
}E+#*R3auB
} K1AI:$H
G>qzAgA
qCi6kEr
w(zlHj
S~.:B2=5K
java代码: nb9qVuAGU
^w/_hY!4/
qM~ev E$%
/*Created on 2005-7-15*/ SxdH%agM
package com.adt.dao.impl; /pt%*;H
\cP\I5IW:s
import java.util.List; >gtKyn]
T\55uQ
import org.flyware.util.page.Page; bwR24>8lP
hz\Fq1
import net.sf.hibernate.HibernateException; V\^3I7F
import net.sf.hibernate.Query; yCy4t6`e
,A
T!:&<X
import com.adt.dao.UserDAO; NguJ[
(,#Rj$W
/** vr+O)/P})
* @author Joa eZ#nZB
*/ m_LW<'
public class UserDAOImpl extends BaseDAOHibernateImpl i Tg?JoE2
VHGOVH,
implements UserDAO { Hr |De8#f
k>I[U}h
/* (non-Javadoc) 9=p^E# d
* @see com.adt.dao.UserDAO#getUserByName })rJU/
i/N4uq}'A<
(java.lang.String) [4KW64%l
*/ 0wU8PZ Nj
publicList getUserByName(String name)throws $@<qaR{t \
8.3888
HibernateException { B#9rqC
String querySentence = "FROM user in class Z[[o u?c
{%.FIw k
com.adt.po.User WHERE user.name=:name"; f0] 8/)
Query query = getSession().createQuery _C$JO
sS/#)/B
(querySentence); Rd7Xs
query.setParameter("name", name); ,iY/\
U''
return query.list(); ~0aWjMc(>
} _-$O6eZ
eY^;L_7}p
/* (non-Javadoc) MQ>.^]B]o
* @see com.adt.dao.UserDAO#getUserCount() {_ti*#
*/ ">PpC]Y1
publicint getUserCount()throws HibernateException { phr6@TI
int count = 0; #K:|@d
String querySentence = "SELECT count(*) FROM `@eo <6
Y>LgpO.
user in class com.adt.po.User"; E~Eh'>Y(B
Query query = getSession().createQuery m&(yx|a4+
`KBgVhS>
(querySentence); OoL#8R
count = ((Integer)query.iterate().next STmn%&
I%.KFPV
()).intValue(); (ds-p[`[m
return count; *)+1BYMo
} lX$6U|!
3#o!K
/* (non-Javadoc) s\A"B#9r
* @see com.adt.dao.UserDAO#getUserByPage Q|/uL`_ni
8q*MhH>6I
(org.flyware.util.page.Page) U9GmkXRix
*/ eV$pza
publicList getUserByPage(Page page)throws vX|ZPn#
#
~SuL3
HibernateException { R?@F%J;tx
String querySentence = "FROM user in class *ILx-D5qr
h$7rEs
com.adt.po.User"; oxT..=-
Query query = getSession().createQuery h>V8YJ
iy_'D
(querySentence); 0?59o!@h
query.setFirstResult(page.getBeginIndex()) A??(}F L
.setMaxResults(page.getEveryPage()); [!9dA.tF
return query.list(); +NL^/y<;
} {Wp+Y9c[
HPJ\]HV(
} )vVt{g
Ln/6]CMl
A;VjMfoB
<8#Q5
DrE
+{Spm
至此,一个完整的分页程序完成。前台的只需要调用 2K?~)q&t*
*c'nPa$+|S
userManager.listUser(page)即可得到一个Page对象和结果集对象 %%J)@k^vH
Z'sAu#C
的综合体,而传入的参数page对象则可以由前台传入,如果用 pGEYke NU
,Y
1&[
webwork,甚至可以直接在配置文件中指定。 ` QC
Qx{k_ye`
下面给出一个webwork调用示例: $%~-p[)<(P
java代码: 0\3mS{s
nk.m Gny
j/"{tMqQp
/*Created on 2005-6-17*/ ^wesuW@=
package com.adt.action.user; *K#7,*Oz
r~ gjn`W
import java.util.List; R'bmE:nL
ILdRN
import org.apache.commons.logging.Log; 5c50F{
import org.apache.commons.logging.LogFactory; `@+}zE
import org.flyware.util.page.Page; nd)Z0%xo
h!# (. P
import com.adt.bo.Result; wcGI2aflD
import com.adt.service.UserService; ).aQ}Gwx^
import com.opensymphony.xwork.Action; h_Ky2IB$
90JD`Nz
/** l!VPk"s
* @author Joa g%()8QxE1
*/ l(X8 cHAi
publicclass ListUser implementsAction{ BxR%\
z"/Mva3|
privatestaticfinal Log logger = LogFactory.getLog 4u}"ng
|GPR3%9
(ListUser.class); 27mGX\T
!O=?n<Ex"
private UserService userService; =@%;6`AVcp
~3k& =3d]
private Page page; l|#WQXs*c{
OU)~
02|\
privateList users; ;A^0="x&
jwsl"zL
/* w`Q"m x*
* (non-Javadoc) 0Y rdu,c
* RiHOX&-7
* @see com.opensymphony.xwork.Action#execute() !e~Yp0gX#
*/ K:PzR,nn
publicString execute()throwsException{ scmn-4j'{
Result result = userService.listUser(page); }$DLa#\-
page = result.getPage(); hjCFN1 #Sa
users = result.getContent(); zh5'oE&[yC
return SUCCESS; dre@V(\;hQ
} X r7pFw
'[u=q
-Lv
/** VayU
* @return Returns the page. OO%<~H
*/ LW?Zd=
public Page getPage(){ ;8WgbR)ZLU
return page; qyXx`'e
} !'uLV#YEZ
>r Nff!Ow
/** Y|ONCc
* @return Returns the users. C;m 7~R
*/ HN'r
ZAZ(
publicList getUsers(){ =)Z!qjf1U
return users; f1R&Q
} rNzsc|a:
1rhsmcE
/** 1d49z9F
* @param page @8zp(1.
* The page to set. .54E*V1
*/ f.f5f%lO~
publicvoid setPage(Page page){ W}+f}/&l
this.page = page; .<`W2*1
} x+~IXi>Ig
|12Cg>;j*n
/** g@WGd(o0)
* @param users a`}b'X:
* The users to set. y/'^r?
*/ -9BKa~ DVQ
publicvoid setUsers(List users){ xw60l&s.\L
this.users = users; l!2hwRR
} 8?qEv,W
eF5?4??
/** RusC5\BUX
* @param userService sA18f2
* The userService to set. tT7< V{i4
*/ wk {9
publicvoid setUserService(UserService userService){ y w"Tw
this.userService = userService; Qxds]5WB/
} W#cr9"'Ta
} `Pj7O/!)#!
6T%5vg_};'
zGz^T
:SxOQ(n
a/@<KnT
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Sz0M8fYT]
ejj|l
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 m35Blg34
j!r4 p,
么只需要: Ph&AP*Fq
java代码: 3[Pa~]yS
YxMOr\B
]a%
*$TF
<?xml version="1.0"?> T!6H5>zA
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1j*I`xZ
'[shY
1.0//EN" "http://www.opensymphony.com/xwork/xwork- _E5%Px5>L
QZufQRfr{
1.0.dtd"> o l67x
1jZ:@M:
<xwork> rI&GM
|
rl)(4ad=
<package name="user" extends="webwork- 9GnNL I{
riI0k{
interceptors"> Z<a6U 3
4)=LOGW
<!-- The default interceptor stack name
TQ&%SMCn
iKB8V<[\T
--> +Q, 0kv
<default-interceptor-ref LV:oNK(
IY|;}mIF
name="myDefaultWebStack"/> W5-p0,?[6
GE$spx
<action name="listUser" R7us9qM4e
v _Bu
class="com.adt.action.user.ListUser"> i|>K
<param _I_Sq,Z#
fk!wq.a
name="page.everyPage">10</param> 8VvoPlo
<result Du>dTi~
VVuL+i
name="success">/user/user_list.jsp</result> #bPio
</action> p$}iBk0B(z
-@ #b<"1
</package> <[xxCW(2
GY4:9Lub7
</xwork> p7(xk6W
Ty%4#9``0
(]0$^!YK
R!xs;|]
)!MeSWGq
'<f4POy!
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 IS7g{:}=p
DLE|ctzj[7
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 )rD] y2^<
zMX7 #,
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 !TY4C`/
\s;]Tg
y]=v+Q*+
~az6n)
(c(c MC'
我写的一个用于分页的类,用了泛型了,hoho ?PWD[mQE\
Ze~ a+%Sb
java代码: 9QJ=?bIC#
>q
<,FY!A
NTiJEzW}
package com.intokr.util; '6{q;Bxo
1rC8]M.N
import java.util.List; Ig1cf9 :
H;,cUb
/** 5(>m=ef"
* 用于分页的类<br> lfu1PCe5
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ^BjwPh4Z#
* DVD}
* @version 0.01 ~! ]FF}6
* @author cheng :<%K6?'@^
*/
N`y!Km
public class Paginator<E> { +IVVsVp
privateint count = 0; // 总记录数 /exV6D r
privateint p = 1; // 页编号 5d|*E_yu
privateint num = 20; // 每页的记录数 7&NRE"?G
privateList<E> results = null; // 结果 OM]p"Jd
{AIP\
/** RrLQM!~
* 结果总数 5<4njo?k
*/ 'O]_A57
publicint getCount(){ iUA2/ A
return count; >;o^qi_$
} xpFu$2T6P.
e }/c`7M
publicvoid setCount(int count){ UuT>qWxQ8
this.count = count;
.EH^1.|v
} {^9,Dy_D
PK3)M'[
/** ci5ERv`
* 本结果所在的页码,从1开始 2DTH|Yv
* yt C{,g>
* @return Returns the pageNo. bEbO){Fe
*/ @Sub.z&T{
publicint getP(){ G#duZNBdc
return p; 60~{sk~E
} *~ 4uF
F.?:Gd1
/** x:;8U i"&B
* if(p<=0) p=1 UOF5&>MLb
* S~YrXQ{_>-
* @param p nP'ab_>b
*/ <3HW!7Ad1
publicvoid setP(int p){ l/LRr.x
if(p <= 0) ezwcOYMXK
p = 1; :@_CQc*yB
this.p = p; n5S$Dl
} |Y/iq9l
#zrD i
/** @[zPN[z.
* 每页记录数量 /RmLV
*/ fLc<}DF
publicint getNum(){ nT|fDD|
return num; ('
`) m
} dSIMwu6u
kp<9o!?)
/** (U!WD`Ym
* if(num<1) num=1 E_WiQ?p
*/ XFYCPET
publicvoid setNum(int num){ :BMU c-[
if(num < 1) wi*Ke2YKP
num = 1; Jd1eOeS
this.num = num; D6bCC;
h=
} 'ycs{}'
`{F8#
/** z(1h ^.
* 获得总页数 CNbrXN
*/ J;m[1Mae&
publicint getPageNum(){ 6xnJyEQUM
return(count - 1) / num + 1; 3zWY%(8t4?
} _PNU*E%s<
O|7q,bEm^
/** Vize0fsD
* 获得本页的开始编号,为 (p-1)*num+1 uT]_pKm
*/ 5?9}^s4
publicint getStart(){ Vl^jTX5N
return(p - 1) * num + 1; S)g5Tu)
} L=Dx$#|
MrOW&7
/** .&r]
?O
* @return Returns the results. n0Ze9W+<
*/ e"^1- U\
publicList<E> getResults(){ MB^b)\X
return results; $Ae/NwIlc
} Kh<v2
;1{S"UY
public void setResults(List<E> results){ N@Slc
0
this.results = results;
Q:_pW<^
} RG*Nw6A
s%4)}w;z
public String toString(){ .fo.mC@a
StringBuilder buff = new StringBuilder YqNhD6
/8W}o/,s5
(); dP)8T
buff.append("{"); pVbX#3
buff.append("count:").append(count); h3@mN\=h'
buff.append(",p:").append(p); n=rPFpRLF
buff.append(",nump:").append(num); *%Gy-5hM
buff.append(",results:").append J|6aa
0pkU1t~9
(results); Mv4JF(,S
buff.append("}"); A*\4C3a'%
return buff.toString(); '^Sa|WXq
} oVC~RKA*
b;soMilz
} K3
]hUe#
,8$;|#d
m}
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