Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 DT`TA#O
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~Rd,jfx
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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 DD`Bl1)
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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 v#1}(
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分页支持类: We&~]-b AW
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java代码: e P]L
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package com.javaeye.common.util; h"Qp e'D}
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import java.util.List; s8L=:hiSf)
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publicclass PaginationSupport { Fk(nf9M%
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publicfinalstaticint PAGESIZE = 30; [B<htD&
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privateint pageSize = PAGESIZE; ctI=|K
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privateList items; ZfM DyS$.
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privateint totalCount; D6X0(pU0
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privateint[] indexes = newint[0]; .nDB{@#
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privateint startIndex = 0; S7i,oP7
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public PaginationSupport(List items, int u^2)oL
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totalCount){ \!`k:lusa
setPageSize(PAGESIZE); >\f'Q Q
setTotalCount(totalCount); Fpe>|"&
setItems(items); ;iA6[uz
setStartIndex(0); t`F<lOKj
} 'PO+P~|oa&
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public PaginationSupport(List items, int M3m)ui z
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totalCount, int startIndex){ LVHIQ9
setPageSize(PAGESIZE); eMT}"u8$A
setTotalCount(totalCount); J}zN]|bz
setItems(items); {$
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setStartIndex(startIndex); _8QHx;}
} B}?$kp
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public PaginationSupport(List items, int fx74h{3u
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totalCount, int pageSize, int startIndex){ ,ma4bqRMc
setPageSize(pageSize); bM@8[&ta
setTotalCount(totalCount); 7Be\^%
setItems(items); aG*Mj;J
setStartIndex(startIndex); S+*%u/;l
} A_pcv7=@
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publicList getItems(){ 9coN >y
return items; R?Ys%~5
} *K#Ci1Q
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publicvoid setItems(List items){ m[w 8|[
this.items = items; ^U;r>[T9h
} _N1UL?
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publicint getPageSize(){ vyhxS .[9
return pageSize; 0}4FwcCr\
} - ]Mbe2;
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publicvoid setPageSize(int pageSize){ )4O* D92
this.pageSize = pageSize; * .P3fVlZ
} 4xsnN@b
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publicint getTotalCount(){ |+h8g@;Z
return totalCount; kf-/rC)>
} 7nl
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publicvoid setTotalCount(int totalCount){ }'c@E0"
if(totalCount > 0){ IzWS6!zKU
this.totalCount = totalCount; _[p@V_my
int count = totalCount / 7a#zr_r
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pageSize; 4+2hj*I
if(totalCount % pageSize > 0) no
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count++; ,]cb3nP
indexes = newint[count]; R) 'AI[la
for(int i = 0; i < count; i++){ Y)KO*40c
indexes = pageSize * a";xG,U
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i; uEE#A0
} eT ZQ[qMp
}else{ >G<.^~o
this.totalCount = 0; j|c6BdROl
} vkg."G:=
} 6JZ$;x{j
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publicint[] getIndexes(){ 6(
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return indexes; *s}j:fJ
} h8-'I=~
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publicvoid setIndexes(int[] indexes){ Z`97=:W
this.indexes = indexes; Q"QL#<N
} %n<.)R
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publicint getStartIndex(){ NX5NE2@^qH
return startIndex; `ek On@T0
} qW(_0<E
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publicvoid setStartIndex(int startIndex){ y|0I3n]e
if(totalCount <= 0) K-f\nr
this.startIndex = 0; q oJ4w7
elseif(startIndex >= totalCount) .}||!
this.startIndex = indexes ;rJ
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[indexes.length - 1]; z,#3YC{'
elseif(startIndex < 0) sxBRg=
this.startIndex = 0; q*kieqG
else{ ^FZ7)T
this.startIndex = indexes TV&4m5
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[startIndex / pageSize]; \mt>R[
} 6opubI<
} %hqhi@q#
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publicint getNextIndex(){ 1>1ii
int nextIndex = getStartIndex() + 9v2(cpZ
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pageSize; }hjJt,m
if(nextIndex >= totalCount) mp x/~`c
return getStartIndex(); x#
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else 1q[vNP=g&
return nextIndex;
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} [@_zsz,`L
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publicint getPreviousIndex(){ }ST0?_0F*
int previousIndex = getStartIndex() - -}?ud3f<
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pageSize; \I4*|6kA
if(previousIndex < 0) h""a#n)q}`
return0; ZoiCdXvTN
else G *f5B
return previousIndex; $]05?JY#
} |5}~n"R5
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} *<**rY*
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抽象业务类 s)e;
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java代码: oR=^NEJv
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/** QPH2TXw
* Created on 2005-7-12 042sjt
*/ _cZ`7]Z
package com.javaeye.common.business; $o"PQ!z
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import java.io.Serializable; GLe(?\Ug=
import java.util.List; O/IW.t
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import org.hibernate.Criteria; u_o>v{&i
import org.hibernate.HibernateException; \kiCczW_
import org.hibernate.Session; 1GY[1M1^
import org.hibernate.criterion.DetachedCriteria; <[^nD>t_
import org.hibernate.criterion.Projections; `F>1xMm
import >?,arER
6 qK0G$>
org.springframework.orm.hibernate3.HibernateCallback; HRx%m1H
import C.{*|#&GAt
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org.springframework.orm.hibernate3.support.HibernateDaoS XbJ=lH
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upport; aW3yl}`{
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import com.javaeye.common.util.PaginationSupport; i4.s_@2Y
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public abstract class AbstractManager extends nm*!#hx
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HibernateDaoSupport { VG'oy
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privateboolean cacheQueries = false; q+32|k>)
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privateString queryCacheRegion; ~Gc+naE>
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publicvoid setCacheQueries(boolean 1+o >#8D
{!B0&x
cacheQueries){ DRi!WWivn
this.cacheQueries = cacheQueries; IgC)YIhd
} 0i$jtCCL(
"Q+'lA[}
publicvoid setQueryCacheRegion(String qo.~5
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queryCacheRegion){ x}1(okc
this.queryCacheRegion = "twV3R
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queryCacheRegion; l~&efAJ-$
} uGJeQ
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publicvoid save(finalObject entity){ Px=/fO G
getHibernateTemplate().save(entity); Yq/|zTe{
} R]/F{Xs
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publicvoid persist(finalObject entity){ [O [N _z
getHibernateTemplate().save(entity); D2>EG~xWq
}
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publicvoid update(finalObject entity){ *kL1r
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getHibernateTemplate().update(entity); #B'WT{B$/~
} &)fPz-s
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publicvoid delete(finalObject entity){ 3Luv$6
getHibernateTemplate().delete(entity); IwFg1\>
} AGCqJ8`|T
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publicObject load(finalClass entity, K
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#)>>f
finalSerializable id){ V%ykHo
return getHibernateTemplate().load )KBv[|
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(entity, id); _V:D7\Gs
} D9H|]W ~
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publicObject get(finalClass entity, 7GK| A{r
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finalSerializable id){ tk}qvW.Ii
return getHibernateTemplate().get A7|"0*62
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(entity, id); A2rr>
} %7
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publicList findAll(finalClass entity){ tMyD^jVC
return getHibernateTemplate().find("from L<8y5B~W
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" + entity.getName()); x:l`e:`y9
} sSD(mO<(
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publicList findByNamedQuery(finalString 5QSd$J
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namedQuery){ 3<JZt.|
return getHibernateTemplate 7)_0jp~2
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().findByNamedQuery(namedQuery); X:62)^~'
} 8<.KWr
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publicList findByNamedQuery(finalString query, *^.b}K%
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finalObject parameter){ %&gx@ \v
return getHibernateTemplate 2EK\QW o
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().findByNamedQuery(query, parameter); C|!E'8Rw
} 9wWjl}%
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publicList findByNamedQuery(finalString query, 2_F`ILCML
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finalObject[] parameters){ f"-<Z_
return getHibernateTemplate cPS!%?}I
sgB3i`_M
().findByNamedQuery(query, parameters); `H+Eo<U
} Xq)'p8C?
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publicList find(finalString query){ :'!?dszS
return getHibernateTemplate().find `L;I/Hp
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(query); &12aI|u^<
} 'GW@P
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publicList find(finalString query, finalObject np>*O }r*
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parameter){ Wq>j;\3b3
return getHibernateTemplate().find T Z>z5YTv
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(query, parameter); 0cS.|\ZTA
} =_,OucKkYG
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public PaginationSupport findPageByCriteria j5/H#_.
*aT!|;
(final DetachedCriteria detachedCriteria){ c2F`S1Nu<
return findPageByCriteria .#Sd|C]R7
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); t(_XB|AKm
} 5?I]\Tb
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public PaginationSupport findPageByCriteria X G^
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(final DetachedCriteria detachedCriteria, finalint Hv
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startIndex){ #pVk%5N
return findPageByCriteria $YSOkyC?
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(detachedCriteria, PaginationSupport.PAGESIZE, )1i)I?m
zf S<X
startIndex); ! TRiFD
} +5HO T{wj
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public PaginationSupport findPageByCriteria kO9yei
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(final DetachedCriteria detachedCriteria, finalint #".{i+3E
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pageSize, \m\.+q]
finalint startIndex){ yqYX<<!V
return(PaginationSupport) |Y99s)2&N
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getHibernateTemplate().execute(new HibernateCallback(){ &\(YmY
publicObject doInHibernate @Ab<I
Y}[r`}={
(Session session)throws HibernateException {
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Criteria criteria = f2Slsl;
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detachedCriteria.getExecutableCriteria(session); C[s*Na-
int totalCount = md2kZ.5u
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((Integer) criteria.setProjection(Projections.rowCount H_2hr[
un/R7"
()).uniqueResult()).intValue(); Zsuh 8t
criteria.setProjection +Rvj]vd}&
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(null); 2V0R|YUt
List items = :I7MP
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criteria.setFirstResult(startIndex).setMaxResults :G`_IB\
%NBD^gF
(pageSize).list(); b9v Kux
PaginationSupport ps = mB,7YZv
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new PaginationSupport(items, totalCount, pageSize, ^aC[ZP:
&O[o;(}mFI
startIndex); Twk zX|
return ps; 6SmSu\lgV
} 0<)8
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}, true); w9oiu$7),
} Gmwn:
9}\T?6?8pX
public List findAllByCriteria(final #eaey+~
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DetachedCriteria detachedCriteria){ ;L`'xFo>>
return(List) getHibernateTemplate g5"g,SFGr
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().execute(new HibernateCallback(){ V-
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publicObject doInHibernate #"Zr#P{P
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(Session session)throws HibernateException { g7H;d
Criteria criteria = 4*54"[9Hr#
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detachedCriteria.getExecutableCriteria(session); ?e@Ff"Y@e
return criteria.list(); @-m&X2J+c
} QA%GK4F70
}, true); 5p>a]gp
} G ;z2}Ei
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public int getCountByCriteria(final z
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DetachedCriteria detachedCriteria){ o#T,vu0s
Integer count = (Integer) &3JbAJ|;X
_
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getHibernateTemplate().execute(new HibernateCallback(){ @ NVq
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publicObject doInHibernate S:5Nh^K
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(Session session)throws HibernateException { HU'd/5fun
Criteria criteria = DB*IVg
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detachedCriteria.getExecutableCriteria(session); _
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return C*KRu`t
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criteria.setProjection(Projections.rowCount uM\~*@
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()).uniqueResult(); o~}q@]]
} 9(iJ=ao (
}, true); &
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return count.intValue(); u'N'<(\k
} nc3 1X
} R#r?<Ofw4
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用户在web层构造查询条件detachedCriteria,和可选的 2L,e\]2Z
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 0nl)0|?Az
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PaginationSupport的实例ps。 b'ew
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ps.getItems()得到已分页好的结果集 bFTWuM
ps.getIndexes()得到分页索引的数组 E]gKJVf9[
ps.getTotalCount()得到总结果数 VE GUhI/d
ps.getStartIndex()当前分页索引 bg$e80
ps.getNextIndex()下一页索引 xi.;`Q^#
ps.getPreviousIndex()上一页索引 <H 3}N!
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3FS:]|oC
#4|?;C)u\
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Ak1f*HGl|
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一下代码重构了。 `yxk
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我把原本我的做法也提供出来供大家讨论吧: 3kJAaI8
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首先,为了实现分页查询,我封装了一个Page类: 7gJ`G@y
java代码: !Hgq7vZG
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/*Created on 2005-4-14*/ 7&+Gv6E
package org.flyware.util.page; t=U[ ;?
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/** q!FJP9x
* @author Joa )"q2DjfX*
* >w
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*/ I]} MK?
publicclass Page { Ot/Y?=j~
|"ck;.)
/** imply if the page has previous page */ PAqziq.
privateboolean hasPrePage; 8T1`TGSFC
/ P{f#rV5
/** imply if the page has next page */ ; xs?^N|
privateboolean hasNextPage; {E@@14]g
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/** the number of every page */ []u!piW
privateint everyPage; *WOA",gZ
}-Zfljj
/** the total page number */ lM?P8#3
privateint totalPage; Z|3l2ucl
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/** the number of current page */ %Uuhi&PA-l
privateint currentPage; lMlXK4-
BPC$ v\a
/** the begin index of the records by the current ~C[R%%Gu
.*v8*8OJ&
query */ `oq
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privateint beginIndex; 0WQ0-~wx
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/** The default constructor */ "WK.sBFz4
public Page(){ >j\zj] -"
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} II),m8G
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/** construct the page by everyPage .w&{2,a3
* @param everyPage CM7j^t
* */ |f`!{=?
public Page(int everyPage){ I:='LH,
this.everyPage = everyPage; 5$N4<Lo7
} [NJ!
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/** The whole constructor */ r@wWGbQ|L
public Page(boolean hasPrePage, boolean hasNextPage, ,TP^i 0
dB< \X.
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int everyPage, int totalPage, <r9J+xh*p
int currentPage, int beginIndex){ 44wY5nYNt
this.hasPrePage = hasPrePage; Hn:%(Rg=aW
this.hasNextPage = hasNextPage; <L:v2 8c
this.everyPage = everyPage; QNn$`Qz.
this.totalPage = totalPage; B*,9{ g0m/
this.currentPage = currentPage; :aco$ZNH5
this.beginIndex = beginIndex; %z1WdiC
} nwW`Q>+#U
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/** Ujb||(W
* @return L
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* Returns the beginIndex. c5^i5de
*/ /q(+r5k \
publicint getBeginIndex(){ 8h-6;x^^
return beginIndex; oZP:}= F
} Qz[~{-<
5U%uS^%DP
/** yn4Xi@9Pri
* @param beginIndex T3!l{vG
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* The beginIndex to set. d\xh>o
*/ >.QD:_@:
publicvoid setBeginIndex(int beginIndex){ aCy2.Qn
this.beginIndex = beginIndex; O*!+D-
} 3E:wyf)i"
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/** I6h{S}2
* @return M
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* Returns the currentPage. c:hOQZ
*/ )vhHlZ *+
publicint getCurrentPage(){ {v<Ig{{V
return currentPage; OZ$u&>916
} _9""3O
qvhTc6oH
/** +X"TiA7{j
* @param currentPage ,7k)cNstW
* The currentPage to set. 9:4P7
*/ ;sCX_`t0E
publicvoid setCurrentPage(int currentPage){ ,$7LMTVDrE
this.currentPage = currentPage; 2u/(Q>#
} 1,9RfY V
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/** {#0B~Zr
* @return HO}aLp
* Returns the everyPage. __'Z0?.4#
*/ <iv9Mg}
publicint getEveryPage(){ sm4@ywd>
return everyPage; #li;L
} )6^b\`
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/** U7bG(?k)
* @param everyPage &3S;5{7_e
* The everyPage to set. ~iydp
*/ ps_CQh0
publicvoid setEveryPage(int everyPage){ h9&<-k
this.everyPage = everyPage; W>/O9?D
} J rYpZ.Nh
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/** GVCyVt[!-
* @return /Y|9!{.
* Returns the hasNextPage. eW0:&*.vMj
*/ pjrVPi5&t
publicboolean getHasNextPage(){ VS1gg4tCv
return hasNextPage; [&3G `8hY
} LHR%dt|M
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/** E':y3T@."
* @param hasNextPage Y')in7g
* The hasNextPage to set. z2wR]G5!
*/ rQ@,Y"
publicvoid setHasNextPage(boolean hasNextPage){ FV!
this.hasNextPage = hasNextPage; /M\S^!g@
} I `p44}D3
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/** (E\7Ui0Q
* @return ,Es5PmV@$%
* Returns the hasPrePage. VL7zU->
*/ ~Se/uL;*
publicboolean getHasPrePage(){ ATPc~f
return hasPrePage; {6a";Xj\e
} SI8mr`gJ
SN\;&(?G
/** =DcKHL(m
* @param hasPrePage 8.'%wOU@A
* The hasPrePage to set. /'!F \ kz
*/ +w%MwPC7`
publicvoid setHasPrePage(boolean hasPrePage){ MpGWt#
this.hasPrePage = hasPrePage; c
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} s:i$ s")
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/** /J wQ5
* @return Returns the totalPage. 3:dQN;=
* wNcf7/ky
*/ 11%^K=dq
publicint getTotalPage(){ $ [M8G
return totalPage; Cf@WjgR
} <?2[]h:wp
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/** 6*tI~
* @param totalPage q71Tg
* The totalPage to set. N r
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*/ +wS?Z5%mU
publicvoid setTotalPage(int totalPage){ Rb',"` 7
this.totalPage = totalPage; !!DHfAV]
} :&9#p%/
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} =uMoX
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}Q/xBC)
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 ko=vK%E[
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个PageUtil,负责对Page对象进行构造: NIQNzq?a^
java代码: P)7SK&]r;=
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/*Created on 2005-4-14*/ cK1r9ED|
package org.flyware.util.page;
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import org.apache.commons.logging.Log; @'7'3+ c
import org.apache.commons.logging.LogFactory; !%_}Rv!JT
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/** '>@evrG
* @author Joa wS hsu_(i
* j_j~BXhIS
*/ K.JKE"j)d
publicclass PageUtil { ApG_Gd.
OLXG0@
privatestaticfinal Log logger = LogFactory.getLog J
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(PageUtil.class); !w(J]<
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/** +%UfnbZ
* Use the origin page to create a new page x32hO;
* @param page |p-, B>p!
* @param totalRecords P>9F(#u_(F
* @return :uSo2d
*/ 2ed$5.D
publicstatic Page createPage(Page page, int LkK%DY
)R(kXz=M
totalRecords){ I~-W4{
return createPage(page.getEveryPage(), ^mv F%"g
f(6`5/C
page.getCurrentPage(), totalRecords); |a*VoMZ
} ^KM' O8
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/** V|13%aE_v
* the basic page utils not including exception KLBU8%
3X=9$xw_
handler EZ:pcnL{
* @param everyPage u!hY
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* @param currentPage 4>-'w MW")
* @param totalRecords ,&e0~
* @return page
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*/ WXV (R,*Tc
publicstatic Page createPage(int everyPage, int 2Tec#eYe
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currentPage, int totalRecords){ Z$LWZg
everyPage = getEveryPage(everyPage); :tBIo7
currentPage = getCurrentPage(currentPage); 1LYz
X;H1
int beginIndex = getBeginIndex(everyPage, RtO3!dGT.
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currentPage); U6cpj
int totalPage = getTotalPage(everyPage,
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"{(|}Cds
totalRecords); ]9qY(m
boolean hasNextPage = hasNextPage(currentPage, ;-sZaU;
_N)/X|=~s
totalPage); @+Yql
boolean hasPrePage = hasPrePage(currentPage); fIe';a
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returnnew Page(hasPrePage, hasNextPage, h K;9XJAf
everyPage, totalPage, K</EVt,U~
currentPage, |ecK~+
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beginIndex); epN>;e z
} 3r^Ls[ey
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privatestaticint getEveryPage(int everyPage){ `(tVwX4
return everyPage == 0 ? 10 : everyPage; K|L&mL&8
} &pHSX
Znr6,[U+q
privatestaticint getCurrentPage(int currentPage){ Y*VF1M,2_
return currentPage == 0 ? 1 : currentPage; k_;g-r,
} abMB-
)qSjI_qt5
privatestaticint getBeginIndex(int everyPage, int +MZsL7%
?vt#M^Q
currentPage){ ~:FF"T>
return(currentPage - 1) * everyPage; M>qqe! c*
} \k4tYL5
uA-1VwW+N
privatestaticint getTotalPage(int everyPage, int [}$jO,H5r
90wGS_P04
totalRecords){ s qXwDy+.
int totalPage = 0; + Vv+<M
A@uU*]TqJ8
if(totalRecords % everyPage == 0) K_!R
totalPage = totalRecords / everyPage; 1;v,rs M
else 35Ro85j
totalPage = totalRecords / everyPage + 1 ; r4 $<,~
rU4;yy*b
return totalPage; P2Jo^WS
} a =
*'
3</W}]$)p
privatestaticboolean hasPrePage(int currentPage){ ^[x6p}$
return currentPage == 1 ? false : true; 'VpzB
s#
} Q~R% |Q{&
o75l&`
privatestaticboolean hasNextPage(int currentPage, ="p,~ivrz
?B+]Ex(\B,
int totalPage){ A)#w~ X4
return currentPage == totalPage || totalPage == E3LEeXcLS
"D,}|
0 ? false : true; _Z>ny&
} BOflhoUX
uc{s\_
j/t)=c
} R]&lVXyH
3xk-D &"
r>#4Sr
~9y/MR
.],:pL9d
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。 1l5'N=hL
VS\| f'E
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 7@R^B =pb
W(}2R>$
做法如下: h,\5C/
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 X2|&\G9c
@;G%7&ps
的信息,和一个结果集List: wRdN(`;v
java代码: 8d?%9# p-)
y@@h )P#
+[ng99p
/*Created on 2005-6-13*/ m*wDJEKo
package com.adt.bo; :q >)c]
63(XCO
import java.util.List; 0GW69 z
mBxMDnh
import org.flyware.util.page.Page; b0sj0w /
]u^ybW"
/** SP\s{,'F-b
* @author Joa Fh/psd
*/ @QMU$]&i]
publicclass Result { O1@3V/.Wu
p"7]zq]'
private Page page; <*I*#WI&B
O2":)zU.
private List content; <Mndr8 H
!UR3`Xk
/** ![!,i\x
* The default constructor ]XcWGQv~
*/ ]4/C19Fe!
public Result(){ XqU0AbQ
super(); '0^lMQMg
} k0&FUO
,k1ns?i9KH
/** )gz]F_
* The constructor using fields o=RxQk1N
* M+M ;@3
* @param page 1h|qxYO
* @param content #]QS
*/ m7`S@qG
public Result(Page page, List content){ .AQTUd(_
this.page = page; @#*{*
S8
this.content = content; P'[ISGt
} mN
l[D
+U<.MVOo.
/** n^rbc;}
* @return Returns the content. nltOX@P-
*/ QE pCU)
publicList getContent(){ $WE=u 9m
return content; ul
b0B"
} qJJ
5o?'
-tx%#(?wH
/** 1;?w#/&t
* @return Returns the page. I FvigDj?
*/ tKeozV[V
public Page getPage(){ 'K}2 m
return page; $m-C6xC/
} 4jlwu0L+
R6`mmJ+'
/** P8H2v_)X&
* @param content C?MKbD=K
* The content to set. Ki1 zi~
*/ <IBUl}|\
public void setContent(List content){ {u0sbb(
this.content = content; 5!wjYQt3
} VZe'6?#
xIV#}z0
/** D+N@l"U{
* @param page
z).&0K
* The page to set. @$CPTv3e
*/ K{9Vyt9,$
publicvoid setPage(Page page){ 0'Qvis[kt
this.page = page; rWqr-"0S.
} il"pKQF
} oA:`=f%\
/Z~$`!J
eYn/F~5-
xX0wn?,~
*5 \'$;Rg
2. 编写业务逻辑接口,并实现它(UserManager, GuaF B[4
DGw*BN%`
UserManagerImpl) ~Y;Z5e=
java代码: &OkPO|
\4
+HNy3
;>fM?ae5
/*Created on 2005-7-15*/ ]3Ibl^J
package com.adt.service; ) 3V1aC
_ /Eg_dQ~@
import net.sf.hibernate.HibernateException; {qU;>;(
YN7OQqa
import org.flyware.util.page.Page; :22wq{
-i_XP]b&
import com.adt.bo.Result; Ls3r( Tf
m( %PZ*s
/** ;#8xRLW
* @author Joa ~BE=z:
*/ 2T@?&N^OD
publicinterface UserManager { (yeWArQ
k!x`cp
public Result listUser(Page page)throws - (q7"h
7j(gW
HibernateException; x^cJ~e2
a]6dhQ`
} 83aWMmA(1
/^gu&xnS
YUyYVi7clq
)jjaY1E
j0n.+CO-{
java代码: u@`y/,PX
/YvwQ
l%?()]y
/*Created on 2005-7-15*/ nQg_1+
package com.adt.service.impl; Hq?dqg' %~
1CJAFi>%D
import java.util.List; 9C!b
f \
7xO~v23oe
import net.sf.hibernate.HibernateException; C}pQFL{B5
pwB>$7(_h
import org.flyware.util.page.Page; ^i8(/iwdJE
import org.flyware.util.page.PageUtil; WA*1_
TQ%F\@"
import com.adt.bo.Result; `_]Ul I_h
import com.adt.dao.UserDAO; I SdB5Va
import com.adt.exception.ObjectNotFoundException; TZ}y%iU:mB
import com.adt.service.UserManager; Q~rE+?n9F
U]9k,#
/** k\g:uIsv$
* @author Joa R+=wSG ]
*/ Ht]O:io`
publicclass UserManagerImpl implements UserManager { Y'#uZA3KA
h}DKFrHW;-
private UserDAO userDAO; C<w&mFozL
X/m~^
/** 58eO|c(
* @param userDAO The userDAO to set. l?Ibq} [~
*/ : JSuC
publicvoid setUserDAO(UserDAO userDAO){ {.e^1qE
this.userDAO = userDAO; k[@/N+;")`
} mrr -jo
6fCHd10!
/* (non-Javadoc) hf7[<I,jov
* @see com.adt.service.UserManager#listUser jx
?"`;a
#%V+- b(
(org.flyware.util.page.Page) k-)Ls~#+
*/ ,3!4
D^
public Result listUser(Page page)throws E@AV?@<sc
,K|UUosS-#
HibernateException, ObjectNotFoundException { 8`90a\t'Z
int totalRecords = userDAO.getUserCount(); SzfMQ@~
if(totalRecords == 0) HuQdQ*Q
throw new ObjectNotFoundException k^zU;
cIrc@
("userNotExist"); +*aC
\4w
page = PageUtil.createPage(page, totalRecords); vI,T1%llu
List users = userDAO.getUserByPage(page); rZ2cC#
returnnew Result(page, users); \p]B8hLW
} %36@1l-N
,ne3uPRu7~
} I~;H'7|e
o7eWL/1
O{Z${TC[
M|{NC`fa
'E\4/0 !
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Iyb_5 UmpF
t 6lwKK
询,接下来编写UserDAO的代码: 3e1P!^'\
3. UserDAO 和 UserDAOImpl: S,Tc\}
java代码: 77ztDQDtM
3Vak
C
q;7DH4;t
/*Created on 2005-7-15*/ c@J@*.q]
package com.adt.dao; Mz\l
C)\B
{<?8Y
import java.util.List; &y(%d 7@/
:+ "H h%
import org.flyware.util.page.Page; E=`/}2
;uzLa%JQ
import net.sf.hibernate.HibernateException; 2<n@%'OQp
N,3iSH=cN[
/** \N$)Q.M
* @author Joa $g/h=w@
*/ sRqecG(n
publicinterface UserDAO extends BaseDAO { 0?dr(
]'-y-kqY
publicList getUserByName(String name)throws 4IvT}Us#+
7R# }AQ
HibernateException; W+$G{XSr5C
[^^ Pl:+
publicint getUserCount()throws HibernateException; dC|6z/
g4952u
publicList getUserByPage(Page page)throws BRM!g9
u8M_2r
HibernateException; ncUS8z
O%N. ;Ve
} yc`*zLWh
\ Ce*5h
={+8jQqi1
kX8NRPW
F\|4zM
java代码: E+#<WK-
m^=El7+
SD<a#S\o
/*Created on 2005-7-15*/ U4<c![Pp.
package com.adt.dao.impl; e =r
b
o. ;Vrc
import java.util.List; w,$qsmR
u3GBAjPsIk
import org.flyware.util.page.Page; TEMxjowr
e}S+1G6r)
import net.sf.hibernate.HibernateException; nw0#gDI|
import net.sf.hibernate.Query; %W)pZN}
$Ery&rX.
import com.adt.dao.UserDAO; ?s3S$Ih
g\
vT7x
/** 9 fYNSr
* @author Joa l
$"hhI8
*/ lg~7[=%k#
public class UserDAOImpl extends BaseDAOHibernateImpl =I)43ahd
i i-AE L
implements UserDAO { UL{J%Ze=~
RZ xwr
/* (non-Javadoc) {G VA4=UAE
* @see com.adt.dao.UserDAO#getUserByName 6/Xs}[iJ
qS FtQ4
(java.lang.String) UNff&E-
*/ E3]WRF;l
publicList getUserByName(String name)throws ^}B,0yUu'
}$4z$&
HibernateException { >[,eK=
String querySentence = "FROM user in class ?'9IgT[*
d%"XsbO
com.adt.po.User WHERE user.name=:name"; X["xC3 i
Query query = getSession().createQuery !NkCki"W
5$D "uAp<V
(querySentence); ElV!C}g
query.setParameter("name", name); 5;U Iz@BJ
return query.list(); -6HwGfU
} xI{4<m/0N
q`b6if"
/* (non-Javadoc) Z,A $h>Z
* @see com.adt.dao.UserDAO#getUserCount() dQ.#8o=
*/ UI+6\ 3
publicint getUserCount()throws HibernateException { O'mcN*
int count = 0; hEQyaDD;
String querySentence = "SELECT count(*) FROM D5D *$IC
@we1#Vz.
user in class com.adt.po.User"; Mzp<s<BX
Query query = getSession().createQuery 7MLLx#U
"J 1A9|
(querySentence); ?<TJ}("/
count = ((Integer)query.iterate().next 49$<:{ ~
7upko9d/
()).intValue(); ]HuB%G|t1V
return count; _9
]:0bDUo
} Y \-W`
~\jP+[>M'
/* (non-Javadoc) V0>X2&.A
* @see com.adt.dao.UserDAO#getUserByPage >8>!wi9U
iM)K:L7d
(org.flyware.util.page.Page) :_~.Nt
*/ QLWnP-
publicList getUserByPage(Page page)throws gHrs|6q9
v$|~
g'6
HibernateException { 3SP";3+
String querySentence = "FROM user in class :*M?RL@j
m-vn5OX
com.adt.po.User"; ;7QXs39S
Query query = getSession().createQuery Mh.1KI[t
10Ik_L='
(querySentence); <\~v$=G
query.setFirstResult(page.getBeginIndex()) _SAM8!q4,
.setMaxResults(page.getEveryPage()); ,X4+i8Yc
return query.list(); [-])$~WfW
} w={q@.
g%
o@e/P;E
} d_@
E4i
Sfz1p
+[!S[KE
S\g9@g.
I'4(Ibl+
至此,一个完整的分页程序完成。前台的只需要调用 ayy\7b
?e$&=FC0;
userManager.listUser(page)即可得到一个Page对象和结果集对象 g
X!>ef
x#D%3v"l_*
的综合体,而传入的参数page对象则可以由前台传入,如果用 p"ZvA^d\
nF <K84
webwork,甚至可以直接在配置文件中指定。 uL`#@nI
SIJ7Y{\.
下面给出一个webwork调用示例: pCs3-&rI3
java代码: FvpU]
^l!SIu
3%kUj
/*Created on 2005-6-17*/ 4>*=q*<V5E
package com.adt.action.user; .|
4P
:r
4v\HaOk
import java.util.List; 9Da{|FyrD
gyw=1q+
import org.apache.commons.logging.Log; |LZ;2 i
import org.apache.commons.logging.LogFactory; eiKY az
import org.flyware.util.page.Page; 'Qy6m'esW
j=l2\W#}
import com.adt.bo.Result; |nefg0`rk
import com.adt.service.UserService; Kjd3!%4mB
import com.opensymphony.xwork.Action; Qr$'Q7
:y-;V
/** .<%tu 0
* @author Joa >G6kF!V
*/ IA2VesHb
publicclass ListUser implementsAction{ \,Y
.5 ?
8G:/f3B=
privatestaticfinal Log logger = LogFactory.getLog msBoInhI
MzIDeZ
(ListUser.class); EN!C5/M{&
41X`.
private UserService userService; qVC+q8
E>bkEm
private Page page; 5whW>T
r1L@p[>
privateList users; gNB+e5[; 2
8z`ZHn3=
/* qUJ"* )S
* (non-Javadoc) /mkT7,]
* W%L'nR~w$
* @see com.opensymphony.xwork.Action#execute() wQ+pVu?6_
*/ rl|'.~mc
publicString execute()throwsException{ ?^Rp"
H
Result result = userService.listUser(page); e
)0 ]WJ
page = result.getPage(); & FhJ%JK
users = result.getContent(); t1w5U+z
return SUCCESS; COh#/-`\1
} q\EYsN</;
!mlfG"FE
/** hVzyvpw
* @return Returns the page. @_ %RQO_X
*/ cMY}Y
[2c
public Page getPage(){ rN}pi@
return page; &
kC
} /~NX<Ye&
A6z,6v6
/** 5#.m'a)
* @return Returns the users. N~!,
S;w
*/ t"VT['8
publicList getUsers(){ hEZvi
return users; *K/K97
} 5iA>Z!sP[
50_[hC&C)
/** wH~A>
4*(
* @param page <m-(B"FX
* The page to set. 7Eyi~jes
*/ `+,?%W)
publicvoid setPage(Page page){ L`nW&;w'
this.page = page; 5A0]+)5E8
} j\ y!
t%qep|
/** =yod
* @param users ^Q8yb*MN
* The users to set. UR'[?
*/ u@_|4Bp,"
publicvoid setUsers(List users){ M/o?D <'
this.users = users; BN 9e S
} =8]`-(
x=DxD&I!J
/** Bp^LLH
* @param userService _lv{ 8vf1B
* The userService to set. z*},N$2=
*/ fpf]qQ
W~7
publicvoid setUserService(UserService userService){ YiZk|K_
this.userService = userService; %0Ur3
} &~_F2]oM
} -}6ew@GE
IW\^-LI.
_[6sr7H!
3 yx[*'e$
ljbAfd
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, 1V2]@VQF
|=q~X}DA
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 M(C">L]8
);!ND%
么只需要: \TP$2i%W
java代码: Q:P)g#suc
%6Gg&Y$j!
_HwA%=>7
<?xml version="1.0"?> c6:uM1V{
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork IHEbT
2;Z
0pPR&
1.0//EN" "http://www.opensymphony.com/xwork/xwork- r?DCR\Jq
'l'3&.{Yfk
1.0.dtd"> :ts3_-cr
O\<zQ2m
<xwork> )BJkHED{
6:8s,a3&[k
<package name="user" extends="webwork- GN_L"|#)=
FAM{p=t]HT
interceptors"> Au2?f~#Fv
Htgo=7!?\3
<!-- The default interceptor stack name B{/og*xd*1
a"@f< wU~
--> N:lE{IvRJ
<default-interceptor-ref ,V1"Typ#<
_<AkM"
name="myDefaultWebStack"/> b+~_/;Y9
Z^'~iU-?
<action name="listUser" T";evM66
sK#)k\w>
class="com.adt.action.user.ListUser"> ST{Vi';}
<param *EuX7LEu_
.))g]CH
name="page.everyPage">10</param> zQ+Mu^|u+
<result 6w<rSU d'
ho=!Yy
name="success">/user/user_list.jsp</result> qt L]x - O
</action> y[b8rv
Q"I(3 tp9[
</package> bUcp8
`}ak]Z_
</xwork> ,=+t2Bn
xgxfPcI
T7nI/y
LzL)qdL
Pg}QRCB@
1o&z