Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 R,!aX"]|
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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 L eUp!
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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 iF##3H$c
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分页支持类: o9D#d\G
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java代码: IQ#Kod;)
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package com.javaeye.common.util; q|B.@Ng.
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import java.util.List;
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publicclass PaginationSupport { l>Zp#+I-
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publicfinalstaticint PAGESIZE = 30; XX1Iw {o9:
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privateint pageSize = PAGESIZE; 0a$hK9BH
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privateList items; KmF+3g~#s
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privateint totalCount; vO;:~
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privateint[] indexes = newint[0]; Ip,0C8T`Q
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privateint startIndex = 0; tdi}P/x
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public PaginationSupport(List items, int AIQ]lQ(
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totalCount){ oM}P Wf-
setPageSize(PAGESIZE); / vzwokH
setTotalCount(totalCount); rYyEs
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setItems(items); g3w-Le&T
setStartIndex(0); s\
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} _l]rt
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public PaginationSupport(List items, int
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totalCount, int startIndex){ JR/^Go$^
setPageSize(PAGESIZE); SI l<\
setTotalCount(totalCount); _@]@&^K$E
setItems(items); :e4[isI
setStartIndex(startIndex); g5~1uU$O
} ")qO#b4
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public PaginationSupport(List items, int 4[LzjC
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totalCount, int pageSize, int startIndex){ 'q*/P&x5
setPageSize(pageSize); Dmk~t="Y
setTotalCount(totalCount); ~gbq^
setItems(items); pdR&2fp
setStartIndex(startIndex); L5>.ku=T
} gY@$g
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publicList getItems(){ \tg}K0E?R5
return items; _i&awm/U
} OY#=s!]
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publicvoid setItems(List items){ ^sVB:?
this.items = items; F;dUqXUu
} )x&}{k6 %
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publicint getPageSize(){ N|WR^MQD
return pageSize; Y]1b39O
} )e:u 6]
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publicvoid setPageSize(int pageSize){ >RT02Ey>
this.pageSize = pageSize; R<-(
} K5q9u-7
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publicint getTotalCount(){ ?IV3"\5
return totalCount; E2{SKIUm
} A&QO]8
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publicvoid setTotalCount(int totalCount){ VFwp .1oa!
if(totalCount > 0){ owc#RW9 7
this.totalCount = totalCount; > jvi7
int count = totalCount / 3YPoObY
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pageSize; R`|GBVbv
if(totalCount % pageSize > 0) [2cG 7A
count++; sHulaX{
indexes = newint[count]; b]U%|bp
for(int i = 0; i < count; i++){ s4c2
indexes = pageSize * _[.3I1kG
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} sIh,@b
}else{ 7*r7Q'
this.totalCount = 0; $n?@zd@53
} ,;yiV<AD
} HGpj(U:`c
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publicint[] getIndexes(){ NrdbXPHceN
return indexes; <ibEo98
} L?e N(L
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publicvoid setIndexes(int[] indexes){ ']ussFaQ
this.indexes = indexes; Cuq=>J
} ?F9:rUyN
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publicint getStartIndex(){ ~vIQ-|8r:
return startIndex; E=Z.v
} [,TuNd
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publicvoid setStartIndex(int startIndex){ Jtxwt[
if(totalCount <= 0) t)O$W
this.startIndex = 0; D
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elseif(startIndex >= totalCount) DLv\]\h}L
this.startIndex = indexes .W<yiB}^
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[indexes.length - 1]; iIoeG_^*Y
elseif(startIndex < 0) 4c*?9r@
this.startIndex = 0; wQX,a;Br
else{ W])<0R52
this.startIndex = indexes L}1|R*b
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[startIndex / pageSize]; @exeHcW61
} Mg0[PbS
} *94<rlh{"
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publicint getNextIndex(){ :!\?yj{{
int nextIndex = getStartIndex() + 4jlUyAD
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pageSize; #?Z>o16,u
if(nextIndex >= totalCount) rn7eY
return getStartIndex(); tN=B9bm3j
else R(sPU>`MX
return nextIndex; p#UrZKR
} _>8ZL)NQQ
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publicint getPreviousIndex(){ ew#t4~hh
int previousIndex = getStartIndex() - WCc,RI0
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pageSize; 1o. O]>
if(previousIndex < 0) qJ b9JL$s
return0; 6.| {l8%r
else :O}= $[
return previousIndex; i"~J -{d}
} ]CD
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} .|Pq!uLvc
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抽象业务类 zU;%s<(p
java代码: %- W3F5NK
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/** /G`'9cD
* Created on 2005-7-12 |UN0jR
*/ XrY\ot`,D
package com.javaeye.common.business; ?CgqHmf\\(
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import java.io.Serializable; x78`dX
import java.util.List; *UVo>;
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import org.hibernate.Criteria; x$o?ckyH
import org.hibernate.HibernateException; bhqBFiuhH
import org.hibernate.Session; ;by`[)
import org.hibernate.criterion.DetachedCriteria; b!C\J
import org.hibernate.criterion.Projections; \a+.~_iL|
import 5\MCk "R!
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org.springframework.orm.hibernate3.HibernateCallback; ztcV[{[g
import p.1@4kgK&r
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org.springframework.orm.hibernate3.support.HibernateDaoS \&K{v#g~
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upport; KTr7z^
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import com.javaeye.common.util.PaginationSupport; N8!V%i?
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public abstract class AbstractManager extends cI~uI'
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HibernateDaoSupport { 3mI(5~4A]?
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privateboolean cacheQueries = false; 5G!0Yy['
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privateString queryCacheRegion; TYv'#{
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publicvoid setCacheQueries(boolean k1l\Rywp
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cacheQueries){ cZB?_[Cp
this.cacheQueries = cacheQueries; }^!8I7J.
} $T.u Iq
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publicvoid setQueryCacheRegion(String vS#Y,H:yAj
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queryCacheRegion){ 0w M2v[^YO
this.queryCacheRegion = BG>fLp
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queryCacheRegion; 1:!_AU?
} !&'GWQY{(
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publicvoid save(finalObject entity){ GtR!a
getHibernateTemplate().save(entity); ! =(OvX_<
} rC`pTN
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publicvoid persist(finalObject entity){ U"nk AW
getHibernateTemplate().save(entity); ,%)O/{p_
} &8p]yo2zO
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publicvoid update(finalObject entity){ hkS0 ae
getHibernateTemplate().update(entity); bTBV:]w
} H7{)"P]{f
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publicvoid delete(finalObject entity){ j) G<PW
getHibernateTemplate().delete(entity); lZ5LHUzP
} k }amSsE
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publicObject load(finalClass entity, Z^tTR]u\$
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finalSerializable id){ Y~E
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return getHibernateTemplate().load `_YXU
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(entity, id); ltQo_k
} i}u,_
}
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publicObject get(finalClass entity, b+=@;0p*6B
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finalSerializable id){ O`?qnNmc;
return getHibernateTemplate().get (,nQ7,2EX
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(entity, id); ` nd/N#
} Qy4eDv5
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publicList findAll(finalClass entity){ 58[=.rzD
return getHibernateTemplate().find("from \#50;
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" + entity.getName()); %C[#:>'+
} mafnkQU
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publicList findByNamedQuery(finalString 6!39t
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namedQuery){ WiU-syNh
return getHibernateTemplate e1<9:h+
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().findByNamedQuery(namedQuery); |WkWZZ^
} V; pRw`
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publicList findByNamedQuery(finalString query, ^X]rFY1
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finalObject parameter){ b=L4A,w~a
return getHibernateTemplate Z= +Tw!wR>
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().findByNamedQuery(query, parameter); ]EN+^i1F[
} j.]ln}b/'+
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publicList findByNamedQuery(finalString query, r+Pfq[z&
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finalObject[] parameters){ ,kQCCn]
return getHibernateTemplate V7 OhOLK8
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().findByNamedQuery(query, parameters); O#_\@f#[
} MZrLLnl6\
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publicList find(finalString query){ */_$' /qV
return getHibernateTemplate().find `w8Ejm?n
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(query); g+j\wvx0
} 7_9^nDU
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publicList find(finalString query, finalObject 2tw3 =)
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parameter){ \? n<UsI
return getHibernateTemplate().find u5.zckV
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(query, parameter); $RA+StF!]
} SpO%nZ";g8
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public PaginationSupport findPageByCriteria Gh5 3Pne
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(final DetachedCriteria detachedCriteria){ x' v-]C(@
return findPageByCriteria 2!)|B
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Vl^p3f[
} 3^Q;On|
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public PaginationSupport findPageByCriteria ^/ff)'.J
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(final DetachedCriteria detachedCriteria, finalint t`-
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startIndex){ LVaJyI@/>
return findPageByCriteria v8"Zru
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(detachedCriteria, PaginationSupport.PAGESIZE, N0pA ,&
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startIndex); *L&|4|BF2
} r,<p#4(>_
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public PaginationSupport findPageByCriteria =TGa\iclpB
);/p[Fd2]
(final DetachedCriteria detachedCriteria, finalint e +Ikw1y"f
*x/H
pageSize, +ovT?CMo
finalint startIndex){ Bun^EJ)
return(PaginationSupport) e>UU/Ks
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getHibernateTemplate().execute(new HibernateCallback(){ ,`ba?O?*G
publicObject doInHibernate ?>1wZ
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(Session session)throws HibernateException { #z61I"kU
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); q%/\
int totalCount = 8]i7wq#=
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((Integer) criteria.setProjection(Projections.rowCount nKmf#
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()).uniqueResult()).intValue(); M4n0GWHLy
criteria.setProjection Cb6K!5[q]
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(null); z:8ieJ)C
List items = o?d`o$
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criteria.setFirstResult(startIndex).setMaxResults <Zo{D |hW
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(pageSize).list(); ><C9PS@
PaginationSupport ps = 6"9(ce
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new PaginationSupport(items, totalCount, pageSize, ,:{+-v(
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startIndex); (~NR."s;
return ps; OD~yIV
} dn&484
}, true); oT!i}TW?o
} 3fUiYI|&7
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public List findAllByCriteria(final !iL6 /
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DetachedCriteria detachedCriteria){ vs{VRc
return(List) getHibernateTemplate dtBr#Te
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().execute(new HibernateCallback(){ XaaR>HljJ
publicObject doInHibernate $k+XH+1CW
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(Session session)throws HibernateException { !Ld[`d.|R!
Criteria criteria = },;Z<(
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detachedCriteria.getExecutableCriteria(session); )=!|^M
return criteria.list(); y,6KU$G
} >x]ir
}, true); k_nQmU>
} M}`T-"qf
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public int getCountByCriteria(final KuF>2KX~Y
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DetachedCriteria detachedCriteria){ " eS-i@
Integer count = (Integer) Z?qc4Cg
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getHibernateTemplate().execute(new HibernateCallback(){ k&:~l@?O
publicObject doInHibernate @W=:r/
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(Session session)throws HibernateException { RLO<5L
Criteria criteria = @cQ
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detachedCriteria.getExecutableCriteria(session); ($!g= 7
return paUJq?Af
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criteria.setProjection(Projections.rowCount 0S\HO<~k
)>N=B 2P
()).uniqueResult(); lI3d
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} Y pvFv-
}, true); /PpZ6ne~[
return count.intValue(); [;#^h/5E
} xs?]DJj
} )h,}v()qc#
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用户在web层构造查询条件detachedCriteria,和可选的 S-79uo
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 /S9n!H:MT
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PaginationSupport的实例ps。 {~V_6wY g
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ps.getItems()得到已分页好的结果集 y(j vl|z[
ps.getIndexes()得到分页索引的数组 i x_a
ps.getTotalCount()得到总结果数 jF{)2|5
ps.getStartIndex()当前分页索引 U8eU[|-8O/
ps.getNextIndex()下一页索引 LbnF8tj}h
ps.getPreviousIndex()上一页索引 fK{Z{)D
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 YVO~0bX:
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 !/Wv\qm
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一下代码重构了。 KA."[dVa
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我把原本我的做法也提供出来供大家讨论吧: G 'CYvV
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首先,为了实现分页查询,我封装了一个Page类: V6b)
java代码: Yt;@@xe&
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/*Created on 2005-4-14*/ r]%.,i7~8
package org.flyware.util.page; 30h1)nQ$h}
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/** `4"&_ltD
* @author Joa d-"[-+)-
* y9Q"3LLic`
*/ Rp.FG
publicclass Page { :LB< z#M
@_?8I_\:
/** imply if the page has previous page */ cKAZWON8;v
privateboolean hasPrePage; j*jq2u
#~ [mn_C
/** imply if the page has next page */ <PQ[N[SU
privateboolean hasNextPage; \JGRd8S[
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/** the number of every page */ <$`udP@
privateint everyPage; pl.=u0 *
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/** the total page number */ !7anJl
privateint totalPage; MM Nz2DEy[
m} nA-*
/** the number of current page */ Alb5#tm:m
privateint currentPage; WR>2t&;E
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/** the begin index of the records by the current Vt
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query */ I\ y>I?X
privateint beginIndex; A\<WnG>xjP
*!+?%e{;b
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/** The default constructor */ +luW=j0V
public Page(){ "O{:jfq
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} D\V
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/** construct the page by everyPage "a>a
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* @param everyPage 6b#J!:?
* */ s)|l-I
public Page(int everyPage){ Gex%~';+q
this.everyPage = everyPage; (
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} VUGVIy.
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/** The whole constructor */ >a1ovKF
public Page(boolean hasPrePage, boolean hasNextPage, AT,?dxP J
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int everyPage, int totalPage, W,)qE^+
int currentPage, int beginIndex){ 5VPP 2;J
this.hasPrePage = hasPrePage; p uLQ_MNV
this.hasNextPage = hasNextPage; as| MB
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this.everyPage = everyPage; eEkbD"Q
this.totalPage = totalPage; RJZ4fl
this.currentPage = currentPage; %O3 r>o=
this.beginIndex = beginIndex; D*#r
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} '5"`H>[
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/** ni x1_Wo;
* @return &tE#1<k
* Returns the beginIndex. OQh(qa
*/ zos#B30
publicint getBeginIndex(){ @VcSK`
return beginIndex; lGP'OY"Q
}
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/** $:MO/Suz{
* @param beginIndex Sud5F4S
* The beginIndex to set. j8gi/07l
*/ 1 ~#p3)B
publicvoid setBeginIndex(int beginIndex){ - '5OX/Szq
this.beginIndex = beginIndex; /.aDQ>
} &D~70N\L
,*@6NK,.
/** p#dpDjh
* @return ,M&[c|
* Returns the currentPage. (PN!k0Y
*/ `Z0#IeX=
publicint getCurrentPage(){ ,HdFE|
return currentPage; <C_FI` wk
} W=EvEx^?%
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/** hol54)7$3:
* @param currentPage Ng3 MfbFG
* The currentPage to set. DOm5 azO!>
*/ TBYRY)~f
publicvoid setCurrentPage(int currentPage){
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this.currentPage = currentPage; glppb$oB\
} L_YVe(dT
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/** T+[N-"N
* @return j@b4)t
* Returns the everyPage. *:}NS8hP
*/ O5Xu(q5+
publicint getEveryPage(){ {^#62Y
return everyPage; x1kb]0s<-
} DN@T4!
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/** \}e1\MiZ
* @param everyPage dEp?jJP$;
* The everyPage to set. }X3SjNd q
*/ !:mo2zA
publicvoid setEveryPage(int everyPage){ 0VB~4NNR
this.everyPage = everyPage; +`x8[A)-
} Osdw\NNH~M
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/** [S/]Vk|4
* @return ]64mSB
* Returns the hasNextPage. *_z5Pa`A
*/ NVMhbpX6
publicboolean getHasNextPage(){ yjVPaEu]aU
return hasNextPage; T}X#I'Z
} +M6qbIO
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/** @hiwq7[j
* @param hasNextPage <;.Zms${@
* The hasNextPage to set. N}>XBZy
*/ mlY0G w_e
publicvoid setHasNextPage(boolean hasNextPage){ 8_K22]c5
this.hasNextPage = hasNextPage; u5EHzoq
}
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/** EIwTx:{F
* @return V>j6Juh
* Returns the hasPrePage. lV-7bZ
*/ )dJaF#6j
publicboolean getHasPrePage(){ H\2+cAFN#
return hasPrePage; % zs 1v]
} ` =!&9o
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/** .foM>UOY
* @param hasPrePage '@ M
* The hasPrePage to set. >yn%.Uoh@
*/ d9[*&[2J|
publicvoid setHasPrePage(boolean hasPrePage){ n}qHt0N
this.hasPrePage = hasPrePage; H'$g!Pg
} XGEAcN
!p1OBS|
/** Gv}*Tw$
* @return Returns the totalPage. 7{:| )
* R R><so%
*/ J56+eC(
publicint getTotalPage(){ B3'qmi<
return totalPage; @xW)&d\'
} d(w
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/** U6"U^
* @param totalPage c@:r\]
* The totalPage to set. LF0gy3
*/ mk1;22o{TX
publicvoid setTotalPage(int totalPage){ H>e?FDs0*R
this.totalPage = totalPage; F9ry?g=h
} ~<3qsA..
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} 8f% @
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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 > >wbyj8
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个PageUtil,负责对Page对象进行构造: zGu(y@o
java代码:
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/*Created on 2005-4-14*/ O: sjf?z
package org.flyware.util.page; KGkzE
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import org.apache.commons.logging.Log; t(CdoE,6
import org.apache.commons.logging.LogFactory; Lm9y!>1"O
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/** er^z:1'
* @author Joa fSl+;|Kn
* >\8Bu#&s4
*/ tuK"}HepB
publicclass PageUtil { =R!=uml(
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privatestaticfinal Log logger = LogFactory.getLog Fm{Ri=X<:
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(PageUtil.class); R3Eh47
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/** $# @G!
* Use the origin page to create a new page }+QgRGQ
* @param page /]T#@>('
* @param totalRecords 31wact^
* @return =+97VO(w]G
*/ NDU,9A.P
publicstatic Page createPage(Page page, int
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totalRecords){ xzy7I6X
return createPage(page.getEveryPage(), ,Vt7Kiu
' G-]>
page.getCurrentPage(), totalRecords); c}Y(Myd
} Rs{L
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/** oKz|hks[6
* the basic page utils not including exception Uq~{=hMX
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handler ! k||-Q&
* @param everyPage 4CS9vv)9R
* @param currentPage `l1{BU
* @param totalRecords KB7CO:
* @return page S3:Pjz}t
*/ _C&2-tnp
publicstatic Page createPage(int everyPage, int <m`HK.|~
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currentPage, int totalRecords){ }-)2CEj3L%
everyPage = getEveryPage(everyPage); [U]*OQH`e
currentPage = getCurrentPage(currentPage); A"\kdxC
int beginIndex = getBeginIndex(everyPage, 4t|g G`QW7
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currentPage); LS Na
int totalPage = getTotalPage(everyPage, %U)/>Z
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totalRecords); D.j'n-yw
boolean hasNextPage = hasNextPage(currentPage, p<'#f,o
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totalPage); oU$Niw9f
boolean hasPrePage = hasPrePage(currentPage); {IYfq)c
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returnnew Page(hasPrePage, hasNextPage, @YMef`T:
everyPage, totalPage, nu}$wLM
currentPage, PNd]Xmv)
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beginIndex); <O?iJ=$
} Z BcZG
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privatestaticint getEveryPage(int everyPage){ '73dsOTIT
return everyPage == 0 ? 10 : everyPage; J8J~$DU\Gv
} iRS )Z)
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privatestaticint getCurrentPage(int currentPage){ n wToZxHZ~
return currentPage == 0 ? 1 : currentPage; >,y291p2
} W @`Nn*S
|zKe*H/
privatestaticint getBeginIndex(int everyPage, int a:Y6yg%1>
\kvd;T#t6
currentPage){ rm;'/l8Y-E
return(currentPage - 1) * everyPage; nY'0*:'u
} 1<fS&)^W
y!6B Gz
privatestaticint getTotalPage(int everyPage, int ANc)igo
KIC5U50J
totalRecords){ d `>M-:dF
int totalPage = 0; &xgMqv2/
s-}|_g.Pt
if(totalRecords % everyPage == 0) s&iM.[k
totalPage = totalRecords / everyPage; ~jH@3\
?-
else D*o_IrG_(
totalPage = totalRecords / everyPage + 1 ; Q`4=
f/~"_O%
return totalPage; F.HD;C-;(
} V'#dY~E-P
_~&6Kb^*
privatestaticboolean hasPrePage(int currentPage){ *$Z}v&-0k
return currentPage == 1 ? false : true; 9s6@AJf
} II3)Cz}xRG
$/Gvz)M
privatestaticboolean hasNextPage(int currentPage, VJDF/)X3$
>E|@3g
+2
int totalPage){ GRB/N1=
return currentPage == totalPage || totalPage == zu5'Ex`gQa
h
+.8Rl
0 ? false : true; ^&zwO7cS
} ,G!M?@Q
@ H=
d8$
AMG}'P:
} ^I~2t|}
=SB#rCH
{^i7 3}@O
S 3Tp__
Q g"hN
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。 hF s:9
01g=Cg
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 >N@tInE
{UX?z?0T
做法如下: /1F%w8Iqh
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %I9{)'+@x
X|q&0W=
的信息,和一个结果集List: rIH/<@+
java代码: 'C8VD+p
[mn@/qf
AqB5B5}
/*Created on 2005-6-13*/ SG_^Rd9
D
package com.adt.bo; 0^az<!!O#
D*6v.`]X
import java.util.List; "CLoM\M)
KtchKpv
import org.flyware.util.page.Page; =dx!R ,Bw
_Db=I3.HJ
/** MP(R2y
* @author Joa K*&M:u6E
*/ Py$Q]s?\1
publicclass Result { 0vuL(W8)
RbzSQr>a\
private Page page; /:3:Ky3
0?KXQD
private List content; -G e5gQ=
n0F.Um
/** FRd!UqMXY
* The default constructor (+68s9XS7
*/ C93BK)$}
public Result(){ 26PUO$&b.
super(); X1&Ug^
} <nlZ?~%}
_BO:~x
/** [bk2RaX:i
* The constructor using fields ^u&oS1U
* oW(lQ'"
* @param page gyj.M`+y
* @param content y=g9 wO
*/ 3I&=1o
public Result(Page page, List content){ ?%%
'GX
this.page = page; njeRzX
this.content = content; )b`Xc+{>
} +PgUbr[p
5LdVcXf
/** {*,~,iq
* @return Returns the content. "X0"=1R~
*/ Oo|*q+{
publicList getContent(){ w
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return content; v,y nz'>)
} 2+zE|I.
^!^6 | [
/** :Rv?>I j
* @return Returns the page. r8g4NsRVtv
*/ ;iR( Ir
public Page getPage(){ tvXoF;Yq
return page; I$/*Pt];
} J ^gtSn^
HM57b>6
/** 1+6:K._C(m
* @param content JTK>[|c9oE
* The content to set. s7.2EkGl=
*/ kP~'C'5Ys
public void setContent(List content){ %Xs3Lz
this.content = content; wmKM:`&[5
} @ODwO;_R5
E
.^5N~.
/** 9zSHn.y
* @param page CT,caa
* The page to set. DP\s-JpI[
*/ ?T=]?[
publicvoid setPage(Page page){ !+T\}1f7d
this.page = page; OLh`R]Sd
} |$"2R3
} !$Aijd s5
]T|9>o!
Xou1X$$z
[p[nK=&r
WeDeD\zy
2. 编写业务逻辑接口,并实现它(UserManager, pm$2*!1F(
L08>9tf`
UserManagerImpl) \Zc$X^}vN
java代码: Q|QVm,m
?#;
oqH<
^2f'I iE
/*Created on 2005-7-15*/ Rs_0xh
package com.adt.service; f?8cO#GU
}/~%Ysl
import net.sf.hibernate.HibernateException; L#sw@UCK
9ZvBsG)
import org.flyware.util.page.Page; fm$eJu
t`NZ_w /
import com.adt.bo.Result; !wiW#PR
?CO\jW_
*n
/** $jT&]p
* @author Joa 2WQKj9iyN
*/ :$k':0 n
publicinterface UserManager { .N2yn`
HR)Dz~Obw
public Result listUser(Page page)throws 5\93-e
OS8 ^mC
HibernateException; I)#=#eI*:
0#(K}9T)
} uC\FW6K=m
dmh6o *
u8ofgcFYE
^0"^Xk*
T}} 0hs;
java代码: N]n]7(e+0C
*Q2;bmIc
C!Cg.^;
/*Created on 2005-7-15*/ 9~+A<X]Hd
package com.adt.service.impl; 7sP;+G
n]M1'yU
import java.util.List; \b{Aj,6,
u I$|M
import net.sf.hibernate.HibernateException; \zj _6Os
s_]p6M
import org.flyware.util.page.Page; $=dp)
import org.flyware.util.page.PageUtil; V]b1cDx{
&<I*;z6%t
import com.adt.bo.Result; YnnpgR.
import com.adt.dao.UserDAO; gcYx-gA}
import com.adt.exception.ObjectNotFoundException; csn/h$`-@
import com.adt.service.UserManager; D'V0b"
.K?',x
/** wMy$T<:
* @author Joa m"Y;GzqQl
*/ .C^1.)
publicclass UserManagerImpl implements UserManager { &`>[4D*
kPwgayz
private UserDAO userDAO; 7#n<d879e%
=Y`P}vI]w%
/** Rz}?@zh_8
* @param userDAO The userDAO to set. n}==
*/ .DSn
H6O
publicvoid setUserDAO(UserDAO userDAO){ (IXiwu
this.userDAO = userDAO; ^l1tQnj)7
} 0_yE74i
F#=XJYG1
/* (non-Javadoc) t~pA2?9@
* @see com.adt.service.UserManager#listUser {MmHR
Ov3W;jD
(org.flyware.util.page.Page) 9k\`3SE
*/ =! v.VF\;
public Result listUser(Page page)throws O+;0|4V%
*S_e:^
HibernateException, ObjectNotFoundException { |\ Nj
int totalRecords = userDAO.getUserCount(); /64jO?mp
if(totalRecords == 0) &tY3nr
throw new ObjectNotFoundException
;/i"W
vQrce&
("userNotExist"); Ta #vD_QP
page = PageUtil.createPage(page, totalRecords); rQiX7
List users = userDAO.getUserByPage(page); EubR]ckB
returnnew Result(page, users); SNP.n))
} d_9Fc"C~
Hj
]$
} gyH'92ck
/x.TF'Z*
Q,Tet&in )
]2G5ng' @
6cof Zc$
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >}QRMn|@H
w?CbATQ
询,接下来编写UserDAO的代码: y e!Bfz>
3. UserDAO 和 UserDAOImpl: EM/NT/
java代码: f@l 6]z{.L
~ZU;0#
kTQ:k
}%B
/*Created on 2005-7-15*/ A7U'>r_.
package com.adt.dao; CG'NC\x5
&{QB}r
import java.util.List; &SS"A*xg
Lm+!/e
import org.flyware.util.page.Page; 8?] :>
'$Jt}O
import net.sf.hibernate.HibernateException; eydVWVN
ln.kEhQ3B
/** $mm =$.
* @author Joa r`u}n
*/ rUfW0
publicinterface UserDAO extends BaseDAO { 3{_A zL
:1u>T3L.z
publicList getUserByName(String name)throws ga#,42)H
tb,.f3;
HibernateException; $w%oLI@kl
,2S
<#p!
publicint getUserCount()throws HibernateException; /2^cty.BXw
J*6I@_{/U
publicList getUserByPage(Page page)throws E%eao$
qG"|,bA
HibernateException; j`Lf/S!}
m}.ru)^p
} Hxr2Q]c?u
WO*yJ`9]
I Vy,A7f
Bc}<B:q%b
`7jm
java代码:
7'FDI`e[
X:-X3mV9{
:NU-C!eT
/*Created on 2005-7-15*/ 475yX-A
package com.adt.dao.impl;
N>`+{
kF'^!Hp
import java.util.List; #1Mk9sxo
EZ #UdK_
import org.flyware.util.page.Page; Y0BvN`E
@RotJl/>
import net.sf.hibernate.HibernateException; O;[PEV~
import net.sf.hibernate.Query; La%\-o
)DMu`cD
import com.adt.dao.UserDAO; )ufHk
%Hv$PsSJ
/** yb/<
7
* @author Joa W9 y8dw.
*/ Orh5d7+S
public class UserDAOImpl extends BaseDAOHibernateImpl uZZ[`PA(
QxnP+U~N
implements UserDAO { rP ;~<IxEr
(Wr;:3i
/* (non-Javadoc) Y^LFJB|b4
* @see com.adt.dao.UserDAO#getUserByName 8DTk<5mW~
1W~-C B>
(java.lang.String) v,vTRrpK
*/ 0!=e1_
publicList getUserByName(String name)throws 3sGrX"0D
OdQ>h$ gZ
HibernateException { o0 -e,F>u
String querySentence = "FROM user in class XBhWj\`(T
QOuy(GY
com.adt.po.User WHERE user.name=:name"; "W6nW
Query query = getSession().createQuery + WPi}
V.WfP*~NJ
(querySentence); S "oUE_>
query.setParameter("name", name); <6/XE@"
return query.list(); q<>2}[W
} UEo,:zeN[
}SitT\%
/* (non-Javadoc) w%S<N
* @see com.adt.dao.UserDAO#getUserCount() js`zQx'
*/ JmNeqpbB`w
publicint getUserCount()throws HibernateException { @usQ*k
int count = 0; +azPpGZ=
String querySentence = "SELECT count(*) FROM PB>p"[ap4
~b\7qx_a9
user in class com.adt.po.User"; JoW*)3Z
Query query = getSession().createQuery p8s2#+/
Oi
BK
(querySentence); U]vNcQj
count = ((Integer)query.iterate().next (/YC\x?
mk\U wv
()).intValue(); ]&/jvA=\l,
return count; ibzYY"D:
} rShi"Yw
*(?YgV
/* (non-Javadoc) C*Ws6s>+z
* @see com.adt.dao.UserDAO#getUserByPage BT>*xZLpS
Aog3d\1$
(org.flyware.util.page.Page) 0nx
<f>n
*/ C,2IET
publicList getUserByPage(Page page)throws ?P`wLS^;
5[l3]HOO
HibernateException { 1+eC'&@Xjt
String querySentence = "FROM user in class 9Z*` {
R5]R
pW=G
com.adt.po.User"; %h|z)
Query query = getSession().createQuery #PXl*~PrQ/
EVO5+
(querySentence); s^C*uP;R
query.setFirstResult(page.getBeginIndex()) `m2F.^qrr
.setMaxResults(page.getEveryPage()); D{N1.rSxv
return query.list(); pMt]wyKr
} ([f6\Pw\ <
x?CjRvT$
} uzp!Y&C
Va=0R
v@>hjie
@Jvw"=
q<c).4
至此,一个完整的分页程序完成。前台的只需要调用 [&NF0c[i
R$6Y\ *L[
userManager.listUser(page)即可得到一个Page对象和结果集对象 0?p_|X'_
Y2<#%@%4
的综合体,而传入的参数page对象则可以由前台传入,如果用 ULU
]k#
#S<>+,Lk
webwork,甚至可以直接在配置文件中指定。 }GkEv}~t
nWXI*%m5
下面给出一个webwork调用示例: :Hd?0eZ|
java代码: sK?[1BI
?rBj{]=
8(3vNuyP
/*Created on 2005-6-17*/ 1&jX~'
package com.adt.action.user; 44%::Oh
>5^Z'!Z"
import java.util.List; [*}[W6
3v
;/oMH/,U8
import org.apache.commons.logging.Log; {qLnwy!i
import org.apache.commons.logging.LogFactory; Mqc[IAcd]
import org.flyware.util.page.Page; 9!9 Gpi
f7s]:n*Ih
import com.adt.bo.Result; P\2QH@p@t
import com.adt.service.UserService; ]-* }-j`
import com.opensymphony.xwork.Action; O)9T|,
U
PI?-gc?[
/** JC =Bxv
* @author Joa 8:s3Q`O
*/ Z]SCIU @+
publicclass ListUser implementsAction{ Nm,vE7M
<[~x]-
privatestaticfinal Log logger = LogFactory.getLog Hlz4f+#I
+ !_^MB kk
(ListUser.class); ;U20g:K
Q 5@~0
private UserService userService; a'T|p)N.;T
j,1,;
private Page page; <EBp X
sXhtn'<v
privateList users; 8:t-I]dzk
a[(n91J0
/* i( c2NPbX
* (non-Javadoc) Q;aZpi-E"
* 8<]> q
* @see com.opensymphony.xwork.Action#execute() a?JU(
*/ x(S064
publicString execute()throwsException{ tY[y? DJ
Result result = userService.listUser(page); *\joaw
page = result.getPage(); l,v:[N
users = result.getContent(); Qy6Avw/$
return SUCCESS; ,%KB\;1mn'
} (j-(fS
>Mvt;'c
/** ^2mXXAQf7^
* @return Returns the page. gcv,]v8
*/
N}dJ)<(2~
public Page getPage(){ *:&fw'vd,
return page; @#T?SNIL5
} p O:
EJ
x &9I2"
/** '6xn!dK
* @return Returns the users. y!v $5wi
*/ @{nT4{
publicList getUsers(){ Vm6^'1CY
return users; wPc,FH+y
} Zy!\=-dSm
~Yr.0i.W
/** (>8fcQUBb
* @param page N@A#e/8
* The page to set. F8=6!Qj
*/ G4RsH/
publicvoid setPage(Page page){ Ko%rB+d
this.page = page; qlgh$9
} Uc6U!X
R/b=!<
/** D:F!;n9
* @param users AVcZ.+?
* The users to set. SU#|&_wtr!
*/ { j/w3
publicvoid setUsers(List users){ t 1&p>
v
this.users = users; ar^`r!ABEh
} $K,aLcu
f
a\cLC
/** fe0 Y^vW
* @param userService &c\8`# 6
* The userService to set. {==Q6BG*
*/ 6C3y+@9
publicvoid setUserService(UserService userService){ #|e<l1 F
this.userService = userService; 6Edqg
} QU#/(N(U#T
} '8Gw{&&
R-h7c!ko
Tl1?5
:qT>m
3AB5Qs<
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ~}M{[6!
keWgbj
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 *Zc-&Dk:Ir
bZlAK)
么只需要: !PQRlgcG
java代码: un/eS-IIh
~j4=PT
LSfj7j`
<?xml version="1.0"?> (*;u{m=
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork jG^~{7#
zeua`jQ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- y7w>/7q
Jg Xbs+.
1.0.dtd"> Zg'[.wov
2
43DdIG$
<xwork> "*T)L<G
[cH/Y2[
<package name="user" extends="webwork- {otvJ|'N
'*-SvA\Cx
interceptors"> I&vB\A
~kHir]jc
<!-- The default interceptor stack name ;zOZu~Q|'
Qz<-xe`o8]
--> Hc+<(g
<default-interceptor-ref E?zp?t:a
+|0 m6)J]
name="myDefaultWebStack"/> 49#-\=<gt
iKK=A.g
<action name="listUser" 3a5H<3w_
givK{Yt<B
class="com.adt.action.user.ListUser"> 8jZYy!
<param F?dTCa
?y
'.sQ
name="page.everyPage">10</param> vbFAS:Y:+
<result
~ 52
i3GvTg-X
name="success">/user/user_list.jsp</result> ;'Y?wH[
</action> -@73" w/
cn#a/Hx
</package> yO($KL+
Z5U~g?
</xwork>
V|D;7
nJ? C 4\#3
>YW>=5_
oO|^ [b#
Q,4F=b
QZfPd\Q5
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 ^w HMKC
y,
Z#?O
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。 =#u2Rx%V
h1Lp:@:|
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 \uYUX~}i"
$-y+97
646yeQ1
M&K@><6k,k
V.F 's(o
我写的一个用于分页的类,用了泛型了,hoho nFP2wvFM
P]TT
java代码: SN+Bmdup
V?"^Ff3m!
=UV?Pi*M>
package com.intokr.util; Y[H_?f=;%
.xx#>Y-\
import java.util.List; 0L1P'*LRU
%pt$S~j
/** 4/jY;YN,2
* 用于分页的类<br> J!H5{7.efN
* 可以用于传递查询的结果也可以用于传送查询的参数<br> pFK
|4u
* (kHR$8GFM
* @version 0.01 j@ "`!uPz
* @author cheng RpXQi*c0
*/ J.&q[
public class Paginator<E> { SUEw5qitB
privateint count = 0; // 总记录数 7HJv4\K
privateint p = 1; // 页编号 </%H 'V@
privateint num = 20; // 每页的记录数 =j{jylC
privateList<E> results = null; // 结果 H>r-|*n
Wf?sJ`.%b
/** *"5a5.`%,
* 结果总数 !G,$:t1-=V
*/ ^Pf&C0xXv
publicint getCount(){ J'EK5=H
return count; M;9+L&p=
} =6dKC_Q
\XN5))
publicvoid setCount(int count){
@b/2'
this.count = count; KH7]`CU
} KCFwO'
mx[^LaR>v
/** o`U\Nhq
* 本结果所在的页码,从1开始 JA}'d7yEa
* ?
1{S_
* @return Returns the pageNo. @Otc$hj
*/ KCu6:)6'
publicint getP(){ oL@ou{iQ
return p; -7$'* V9$
} ""+*Gn7^8
pd1m/:
/** Psa8OJan
* if(p<=0) p=1 kziBHis!
* OT[m
g4&
* @param p .g#=~{A
*/ {Y"r]:5i
publicvoid setP(int p){ -FR ;:
if(p <= 0) L8zqLDi&
p = 1; a7|&Tbv
this.p = p; ;40m goN
} <f6PULm
$.1'Ym
/** HH#i.s2
* 每页记录数量 PPPwDsJ
*/ }ELCnN
publicint getNum(){ de6dLT>m
return num; nnNg^<[k3
} t4*A+"~j
%MJ7u}
/** &-:yn&f7
* if(num<1) num=1 ;5k|gW
*/ ~K96y$ DTE
publicvoid setNum(int num){ ) R@gnTe
if(num < 1) DxgT]F%
num = 1; gk1S"H
this.num = num; orHD3T%&
} 5r<(Z0
j*u9+.
/** ewG21 q$
* 获得总页数 \Ji2uGT
*/ :\JbWj_j
publicint getPageNum(){ N^]>R:Stu
return(count - 1) / num + 1; 4Jr[8P0/A9
} \#jDQ
/&d`c=nH
/** A4FDR#
* 获得本页的开始编号,为 (p-1)*num+1 CD1=2
*/ _0["J:s9
publicint getStart(){ /A.i5=k
return(p - 1) * num + 1; /&:9VMMj
} PJ@ ,01
*UoHzaIqz
/** ()#tR^T
* @return Returns the results. "3|"rc&F#
*/ !#I/be]
publicList<E> getResults(){ &n.uNe
return results; 5{0>7c|.
} eKz~viM'
+i#sS19h
public void setResults(List<E> results){ '?gIcWM
this.results = results; w%dIe!sV
} K!K"}%/_
XHM"agrhSQ
public String toString(){ W+
'}O<
StringBuilder buff = new StringBuilder 7B\(r~f`t
]3,.g)U*m
(); r_,m\'~s!
buff.append("{"); 64' ]F1p0
buff.append("count:").append(count); !TL}~D:J
buff.append(",p:").append(p); K('lH-3wS
buff.append(",nump:").append(num); 51opP8
buff.append(",results:").append d 4\E
Pd "mb~
(results); d"6]?
buff.append("}"); -,A5^>}%,Y
return buff.toString(); m'(;uR`
} >X,Ag
fEG3b#t N
} Gi2ad+QH-
H\+c'$
5%+bWI{w