Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Pc(2'r@#
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 "3^6
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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 g{D&|qWj
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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 "QlCcH`g
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分页支持类: {UUVN/$
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java代码: }pTj8Tr
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package com.javaeye.common.util; 9
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import java.util.List; 2
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publicclass PaginationSupport { w{r->Phe
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publicfinalstaticint PAGESIZE = 30; vEgJmHv;
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privateint pageSize = PAGESIZE; J-QQ!qa0
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privateList items; 2;&13%@!
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privateint totalCount; We4 FR4`
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privateint[] indexes = newint[0]; YT3QwN9
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privateint startIndex = 0; rxz3Mqg
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public PaginationSupport(List items, int siG?Sd_2
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totalCount){ C )I"yeS.
setPageSize(PAGESIZE); DQ9s57VxC!
setTotalCount(totalCount);
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setItems(items); ^y3\e
setStartIndex(0); #k"[TCQ>
} xUw\Y(!
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public PaginationSupport(List items, int Bdg*XfXXk
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totalCount, int startIndex){ a-}%R
setPageSize(PAGESIZE); 54;iLL
setTotalCount(totalCount); Sx ~_p3_5U
setItems(items); RXof$2CZS
setStartIndex(startIndex); '~f@p~P
} cp2fDn
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public PaginationSupport(List items, int 7]^ }
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totalCount, int pageSize, int startIndex){ )N6R#
setPageSize(pageSize); p/5!a~1'xN
setTotalCount(totalCount); zbi
setItems(items); \=_8G:1
setStartIndex(startIndex); 0Fw\iy1o
} e7?W VV,
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publicList getItems(){ "p;DQ-V
return items; "''<:K|
} m0*
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publicvoid setItems(List items){ TZP{=v<
this.items = items; mQvKreo~
} m@Nx`aS?
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publicint getPageSize(){ |HU
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return pageSize; ]q3Kd{B
} 7E5Dz7
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publicvoid setPageSize(int pageSize){ c@^:tB
this.pageSize = pageSize; F@*lR(4C
} ?% X9XH/!
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publicint getTotalCount(){ ^kD?0Fm
return totalCount; qN0#=X
} |)4$\<d
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publicvoid setTotalCount(int totalCount){ ]dK]a:S
if(totalCount > 0){ q5!l(QL.
this.totalCount = totalCount; )f!dG(\
int count = totalCount / 48ma&f;
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pageSize; ,%'0e/
if(totalCount % pageSize > 0) &0eB@8{N
count++; cMWO_$
indexes = newint[count]; L@_">'pR
for(int i = 0; i < count; i++){ F=om^6G%X5
indexes = pageSize * 4QN;o%,
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i; lp}WB d+
} ^0|NmMJ]
}else{ cORM R!
this.totalCount = 0; m3(T0.j0P
} huoKr
} P{Z71a5
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publicint[] getIndexes(){ _o?(t\B9{
return indexes; 05KoxFO?
} N
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publicvoid setIndexes(int[] indexes){ W#L"5pRg
this.indexes = indexes;
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} `zp2;]W
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publicint getStartIndex(){ bXH^Bm
return startIndex; 0#[f2X62B
} VDKS_n
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publicvoid setStartIndex(int startIndex){ !"J#,e|
if(totalCount <= 0) uK:-g,;
this.startIndex = 0; 0c61q Q6
elseif(startIndex >= totalCount) f4I#a&DO
this.startIndex = indexes
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[indexes.length - 1]; ]kkBgjQbS
elseif(startIndex < 0) 8KtgSash
this.startIndex = 0; z>33O5U
else{ +w.Kv
;
this.startIndex = indexes _qeuVi=A
ij(4)=
[startIndex / pageSize]; HQ3`:l
} @7s,|\
} &U~r}=
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publicint getNextIndex(){ iEviH>b5
int nextIndex = getStartIndex() + jN%p5nZ^EK
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pageSize; NceB'YG|
if(nextIndex >= totalCount) t/*K#]26
return getStartIndex(); 7+a%ehwU
else F> QT|
return nextIndex; `f+8WPJPZ
} dBMe`hM)
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publicint getPreviousIndex(){ N4H+_g|
int previousIndex = getStartIndex() - Yc82vSG'
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pageSize; As+;qNO
if(previousIndex < 0) N
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return0; W/r mm*
else {?/8jCVd
return previousIndex; `GQiB]Z
} ,![Du::1
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} P$3=i`X!nw
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抽象业务类 oKYhE
java代码: aw/7Z`
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/** x$n~f:1Y
* Created on 2005-7-12 N<06sRg#
*/ V(2,\+ t
package com.javaeye.common.business; +^*5${g;@H
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import java.io.Serializable; O<1vSav!K
import java.util.List; ~zxwg+:QO
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import org.hibernate.Criteria; /> 3
import org.hibernate.HibernateException; Q)Iv_N/
import org.hibernate.Session; icPp8EwH
import org.hibernate.criterion.DetachedCriteria; 'cZMRRc<
import org.hibernate.criterion.Projections; b6nZ55 h
import $>r>0S#+\&
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org.springframework.orm.hibernate3.HibernateCallback; @0z0m;8
import #P%1{l5m
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org.springframework.orm.hibernate3.support.HibernateDaoS Or+*q91j
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upport; <!~1{`n%9J
@VC .>
import com.javaeye.common.util.PaginationSupport; LZr0]g{Pu/
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public abstract class AbstractManager extends (!*Xhz,(-
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HibernateDaoSupport { Pr5g6I'G
" ^HK@$
privateboolean cacheQueries = false; ]$~Fzs
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privateString queryCacheRegion; +UK%t>E8
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publicvoid setCacheQueries(boolean pw,O"6J*
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cacheQueries){ @S}/g/+2
this.cacheQueries = cacheQueries; )sW6iR&_i
} f]tv`<Q7
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publicvoid setQueryCacheRegion(String Z5G]p4
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queryCacheRegion){ ietRr!$.
this.queryCacheRegion = sI&i{D
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queryCacheRegion; =db'#m{$
} K(nS$x1G
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publicvoid save(finalObject entity){ L*g.
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getHibernateTemplate().save(entity); w9RF2J
} |[S90Gw]
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publicvoid persist(finalObject entity){ 4_PCqEp)
getHibernateTemplate().save(entity); pOC% oj
} f64(a\Rw!^
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publicvoid update(finalObject entity){ $hkq>i \
getHibernateTemplate().update(entity); +|y*}bG
} |KL')&"
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publicvoid delete(finalObject entity){ ?y~TC qV
getHibernateTemplate().delete(entity); Q6"uK
} gNShOu
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publicObject load(finalClass entity, M|\^UF2e
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finalSerializable id){ Y3-gUX*w0
return getHibernateTemplate().load 25 CZmsg
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(entity, id); Kv(z4 z
} *~p(GC
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publicObject get(finalClass entity, 8b|OXWl
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finalSerializable id){ [SVhtrx|%
return getHibernateTemplate().get )4l>XlQ&
'|A|vCRCG
(entity, id); TG}d3ZU
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} %$@1FlqX;
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publicList findAll(finalClass entity){ qnB<k,8T
return getHibernateTemplate().find("from N]NF\7(
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" + entity.getName()); 2{bhA5L
} _V@WNo%B
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publicList findByNamedQuery(finalString *5_V*v6
~q)u(WC|
namedQuery){ 7kKuZW@K-
return getHibernateTemplate 7R}9oK_I
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().findByNamedQuery(namedQuery); Wf#VA;d
} _;56^1'T
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publicList findByNamedQuery(finalString query, F^QQ0h]2
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finalObject parameter){ {C3U6kKs;R
return getHibernateTemplate ui:=
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().findByNamedQuery(query, parameter); jMM$ d,7B
} ,~COZi;R.D
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publicList findByNamedQuery(finalString query, 8WL8/
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finalObject[] parameters){ 1B|8ZmFJj
return getHibernateTemplate Z$p0&~
bB!#:j>(v
().findByNamedQuery(query, parameters); 8)N@qUV
} a5@z:i
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publicList find(finalString query){ UiH!Dl}<
return getHibernateTemplate().find oH^(qZ8W
%Y]=1BRk}
(query); (D<(6?
} #2RiLht
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publicList find(finalString query, finalObject G O{.9_2
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parameter){ !*aPEf270
return getHibernateTemplate().find Z\~GU*Y.e
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(query, parameter); #`(WUn0H?
} {o0qUX>[
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public PaginationSupport findPageByCriteria sV/l5]b]
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(final DetachedCriteria detachedCriteria){ UDy(dn>J:J
return findPageByCriteria W3r?7!~
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); g:7,~}_}^
} aZ X mlq
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public PaginationSupport findPageByCriteria Fk"Ee&H)(
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}rh
(final DetachedCriteria detachedCriteria, finalint k1^\|
8'Z:ydj^,
startIndex){ ]0c+/ \b&
return findPageByCriteria |F[=b'?
j'?7D0>
(detachedCriteria, PaginationSupport.PAGESIZE, YAVy9$N-
a,|?5j9,P
startIndex); ?m7:if+y
} ujFzJdp3k
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public PaginationSupport findPageByCriteria Aw5pd7qKL
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(final DetachedCriteria detachedCriteria, finalint b| M3`
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pageSize, yF13Of^l./
finalint startIndex){ :O-iykXyI
return(PaginationSupport) 5O<>mCF
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getHibernateTemplate().execute(new HibernateCallback(){ >&,[H:Z
publicObject doInHibernate HOoPrB m
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(Session session)throws HibernateException { OFk8 >"|
Criteria criteria = gU&%J4O
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detachedCriteria.getExecutableCriteria(session); Pq9|WV#F5/
int totalCount = yWDTjY/
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((Integer) criteria.setProjection(Projections.rowCount urBc=3Rz
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()).uniqueResult()).intValue(); B9R(&<4
criteria.setProjection ^qGb%! l
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,SD#
(null); 0NDftcB]
List items = *\}}Bv+9
mLh kI!4[
criteria.setFirstResult(startIndex).setMaxResults dS2G}L^L
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(pageSize).list(); p;T{i._iL
PaginationSupport ps = h!rM^
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new PaginationSupport(items, totalCount, pageSize, /ID3s`D)
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startIndex); E/M_lvQ
return ps; =Prb'8 W
} : _e#
}, true); Byl^?5
} ?BA]7M(,4
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public List findAllByCriteria(final $+JS&k/'m
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DetachedCriteria detachedCriteria){ Wj|alH9<
return(List) getHibernateTemplate gr-9l0u
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().execute(new HibernateCallback(){ o?L'Pg
publicObject doInHibernate YB<*"HxM)}
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(Session session)throws HibernateException { ?eH&'m}-
Criteria criteria = "@R>J?Cc+
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detachedCriteria.getExecutableCriteria(session); 2H71~~ c
return criteria.list(); }KUd7[s
} GSclK|#tE
}, true); q6Rr.A
} q<y#pL=k"*
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public int getCountByCriteria(final :y*NM,s
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DetachedCriteria detachedCriteria){ >~%e$a7}+
Integer count = (Integer) +#U|skl
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getHibernateTemplate().execute(new HibernateCallback(){ **9x?s
publicObject doInHibernate n0Y+b[+wj
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(Session session)throws HibernateException { $mf
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Criteria criteria = ,.eWQK~
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detachedCriteria.getExecutableCriteria(session); lC:k7<0Ji
return |4$M]M f0
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criteria.setProjection(Projections.rowCount `&\Q +W
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()).uniqueResult(); +$4(zPs@
} L,y6^J!
}, true); 8n1'x;
return count.intValue(); !cKz7?w
} B9p?8.[
} rpeJkG@+
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用户在web层构造查询条件detachedCriteria,和可选的 V5+SWXZ
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 oFOnjK"|F
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PaginationSupport的实例ps。 o FjIA!
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ps.getItems()得到已分页好的结果集 z/i+EE
ps.getIndexes()得到分页索引的数组 21k5I #U
ps.getTotalCount()得到总结果数 fXrXV~'8
ps.getStartIndex()当前分页索引 ^u3V
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ps.getNextIndex()下一页索引 f0Bto/,>~
ps.getPreviousIndex()上一页索引 LU!dN "[k
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 gV&z2S~"
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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 WJI[9@^I~
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一下代码重构了。 ECv)v
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我把原本我的做法也提供出来供大家讨论吧: E=){K
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首先,为了实现分页查询,我封装了一个Page类: eQQ>
java代码: ^CwR!I.D}4
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/*Created on 2005-4-14*/ g{5A4|_7
package org.flyware.util.page; >X*Mio8P#
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/** ,3nN[)dk
* @author Joa OY?y ^45y
* JN7k 2]{
*/ !^Q.VYY
publicclass Page { $-[CG7VgX%
1S@vGq}
/** imply if the page has previous page */ q^6 +!&"
privateboolean hasPrePage; B]tIi^
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/** imply if the page has next page */ DxJX+.9K9
privateboolean hasNextPage; 'Ei;^Y 1e
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/** the number of every page */ zt^48~ry
privateint everyPage; 2t $ j
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/** the total page number */ 'M3">$N
privateint totalPage; 610D%F
WxF:~{
/** the number of current page */ aL\nT XakX
privateint currentPage; j <o3JV
p!s}=wI`
/** the begin index of the records by the current !
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query */ {d?$m*YR3`
privateint beginIndex; 6oui]$pH
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/** The default constructor */ "s\L~R.&
public Page(){ 3"F`ZJ]=
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} 86z]<p (
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@2PGEl
/** construct the page by everyPage 4b:s<$TZ
* @param everyPage 2B,] -Mu)
* */ dx;k`r$w
public Page(int everyPage){ +iI&c
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this.everyPage = everyPage; D-,L&R!`
} fryJW=
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/** The whole constructor */ : }`-B0
public Page(boolean hasPrePage, boolean hasNextPage, 6 PxW8pn
u :F~K
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int everyPage, int totalPage, Z{H5oUk
int currentPage, int beginIndex){ bGorH=pb5R
this.hasPrePage = hasPrePage; 7#wn<HDY%
this.hasNextPage = hasNextPage; F]9nB3:W
this.everyPage = everyPage; &d'Awvy0
this.totalPage = totalPage; &N;-J2M
this.currentPage = currentPage; ] Eh}L
this.beginIndex = beginIndex; Y6&wJ<
} +*_5tWAc
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/** `)QCn<
* @return z)uuxNv[R
* Returns the beginIndex. uPniLx\t:
*/ Y[ N^p#t{
publicint getBeginIndex(){ lSH6>0#B
return beginIndex; \%p34K\
} yS=oUE$
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/** u a\,->
* @param beginIndex "]-Xmdk09
* The beginIndex to set. u<nLag
*/ ,~?YBLw@c
publicvoid setBeginIndex(int beginIndex){ RN@ctRS
this.beginIndex = beginIndex; h`3eu;5)
} a<fUI%_
8|$3OVS
/**
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* @return \o';"Q1H
* Returns the currentPage. z,|{fKtY}
*/ qgDRu ]ba
publicint getCurrentPage(){ }mZwd_cK
return currentPage; LzCw+@-umw
} WQHd[2Z#e
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/** |`;54_f
* @param currentPage It75R}B
* The currentPage to set. !\g+8>
*/ 1nu^F,M
publicvoid setCurrentPage(int currentPage){ }@r{?8Ru
this.currentPage = currentPage; Ve
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} )Jv[xY~
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/** t>H`X~SR?
* @return K).n.:vYZ
* Returns the everyPage. )IJQeC
*/ *FJZiPy
publicint getEveryPage(){ _.-;5M-
return everyPage; =r@vc
} r$wxk 4%Rz
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/** x\Y $+A,P
* @param everyPage "al`$ %(
* The everyPage to set. #h@J=Ki
*/ \Y}3cE
publicvoid setEveryPage(int everyPage){ J sEa23
this.everyPage = everyPage; P<K){V
} F9*g=
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/** ^S6u<,
* @return pZU9^Z?~6
* Returns the hasNextPage. IMk'#)
*/ (os$B
publicboolean getHasNextPage(){ >YUoh-]`
return hasNextPage; 7G)H.L)$m"
} :EHJ\+kejX
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/** 0dh=fcb
* @param hasNextPage " ZX3sfkh
* The hasNextPage to set. )3h^Y=43
*/ Iz[@^IUx=
publicvoid setHasNextPage(boolean hasNextPage){ 0D8K=h&e
this.hasNextPage = hasNextPage; Y-0?a?q2Fr
} =f(cH152T
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/** 4R5D88=C
* @return f>ZyI{
* Returns the hasPrePage. "}Me}S<
*/ :eZh'-c?
publicboolean getHasPrePage(){ 4ikd M/
return hasPrePage; "YB**Y
} ?3O9eZY@
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/** A*|cdY]HP
* @param hasPrePage [le)P$#z
* The hasPrePage to set. ai*f
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*/ i>[_r,-\[
publicvoid setHasPrePage(boolean hasPrePage){ u=YX9Mo!
this.hasPrePage = hasPrePage; Qeu\&%C!<
} |X`/
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/** !pJeA)W;
* @return Returns the totalPage. j w* IO
* S"wg2X<
*/ .Q)|vq^
publicint getTotalPage(){ /cZ-tSC)o
return totalPage; cT\I[9!)
} ^V|Oxp'7_
;=? ~
-_
/** oBUxKisW
* @param totalPage )a3IQrf=
* The totalPage to set. IL_d:HF|1
*/ ;sch>2&ZWU
publicvoid setTotalPage(int totalPage){ ejA%%5q
this.totalPage = totalPage; Erk?}E
} 0<TD/1wN
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} &P,^.'
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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 Zatf9yGD
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个PageUtil,负责对Page对象进行构造: *6U&Qy-M
java代码: 5
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/*Created on 2005-4-14*/ }oJAB1'k
package org.flyware.util.page; Ys8SDlMo
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import org.apache.commons.logging.Log; 1T)Zh+?)}
import org.apache.commons.logging.LogFactory; 5b/ojr7
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/** v_<2H'*Q
* @author Joa R4Rb73o
* irk*~k ?
*/ b6E<r>q
publicclass PageUtil { ^h&I H|
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privatestaticfinal Log logger = LogFactory.getLog 7DlOW1|
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(PageUtil.class); S-#q~X!yJ
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/** [i]r-|_K
* Use the origin page to create a new page
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* @param page iK{T^vvk
* @param totalRecords 6Fy@s
* @return V,EF'-F
*/ YRlDX:oX~
publicstatic Page createPage(Page page, int wNE$6
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totalRecords){ $j)hNWI
return createPage(page.getEveryPage(), -RJE6~>'\
irTv4ZE'+l
page.getCurrentPage(), totalRecords); woq)\;CK
} ~2u\
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/** $\AEWFB
* the basic page utils not including exception G%#05jH
!MQN H
handler W4YE~
* @param everyPage T@^]i&
* @param currentPage 1px\K8
* @param totalRecords 5(&xNT-n8
* @return page =neL}Fav56
*/ *@V*~^V"J[
publicstatic Page createPage(int everyPage, int ^Jp*B;
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currentPage, int totalRecords){ NBl
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everyPage = getEveryPage(everyPage); wHsB,2H
currentPage = getCurrentPage(currentPage); |dadH7
int beginIndex = getBeginIndex(everyPage, ZEbLL4n
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currentPage); MEwdw3
int totalPage = getTotalPage(everyPage, &~5=K
,ZI\dtl
totalRecords); GO5 ~!g
boolean hasNextPage = hasNextPage(currentPage, 6xgv:,
>Cd9fJ&0gP
totalPage); -+U/Lrt>8
boolean hasPrePage = hasPrePage(currentPage); %Ny) ?B
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returnnew Page(hasPrePage, hasNextPage, k3@HI|
everyPage, totalPage, g8pm2o@S
currentPage, -.vDF?@G
zREJ#r
beginIndex); p {%t q$}.
} YT2'!R
1
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privatestaticint getEveryPage(int everyPage){ nJ3vi}`
return everyPage == 0 ? 10 : everyPage; 2f:Mm'XdB
} =g@9>3~{!
nbvkP
privatestaticint getCurrentPage(int currentPage){ {`.O|_b
return currentPage == 0 ? 1 : currentPage; wFlV=!>,
} DOL%'k ?B
Sw!
j=`O
privatestaticint getBeginIndex(int everyPage, int & QZV q"
m =&j@
currentPage){ (N U0Tw
return(currentPage - 1) * everyPage; M$CVQ>op:
} Q2~5"
q/6UK =
privatestaticint getTotalPage(int everyPage, int &y:CW>T$/X
<Dw]yGK@
totalRecords){ 'm1. X-$V
int totalPage = 0; Z6=~1'<X
,# "(Z
if(totalRecords % everyPage == 0) kN'Thq/ZE
totalPage = totalRecords / everyPage; a[O6YgO
else dl/X."iv!
totalPage = totalRecords / everyPage + 1 ; |"}4*V_ *
Q&+c.S
return totalPage; *PB/iVH%6
} 8j\d~Lw=
ujx-jIhT_
privatestaticboolean hasPrePage(int currentPage){ 52<~K
return currentPage == 1 ? false : true; R#6H'TVE
} >rRf9wO1l
.98.G4J>
privatestaticboolean hasNextPage(int currentPage, 9.Ap~Ay.
A
+!sD5d
int totalPage){ <:cpz* G4
return currentPage == totalPage || totalPage == 6D*chvNA;
w4OW4J#
0 ? false : true; i=da,W=0
} MuSaK %
b{HhS6<K?
[#X|+M&u6
} F^sw0 .b
;tN4HiN
-h9#G{2W[
X<K9L7/*
9%TT>2#
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 #O6
EP#B
C"9"{
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 <rMv0y+r
zn[QvY
做法如下: zW)gC9_|m-
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 :tlE`BIp
5h(jeT8"
的信息,和一个结果集List: 3*2I$e!Jt
java代码: Ge~,[If+
4zX=3iBt
0&B:\
/*Created on 2005-6-13*/ :s-EG;.
package com.adt.bo; >@:667i,`
y;,y"W
import java.util.List; OgTSx
Lv3XYZgW~
import org.flyware.util.page.Page; :B+Rg cqi
To^#
0
/** /THNP 8.
* @author Joa 6ZTaQPtm
*/ Zr9 d&|$
publicclass Result { x i.IRAZX
a G@nErdW
private Page page; yYB NH1
A8mlw#`E8b
private List content; p}f-c
/o\U/I
/** }"0{zrz
* The default constructor .5^a;`-+
*/ fo;6huz
public Result(){ m6eFXP1U
super(); gs-@hR.,s0
} \"J?@
(`F|nG=X
/** jF4csO=E
* The constructor using fields (>mi!:
* ?^Pq/VtZ
* @param page |a>}9:g,=*
* @param content Y.(v{l
*/ Q;Q%SI`yT
public Result(Page page, List content){ Wge ho
this.page = page; ;raz6DRO
this.content = content; 2aFT<T0
} PaxK^*
/Ht/F)&P
/** **.:)
* @return Returns the content. D {Oq\*
*/ 8s~\iuk
publicList getContent(){ _HLC>pH~#
return content; T!1SMo^
} +8^5C,V
&adY
/** }'DC
Q
* @return Returns the page. ENO? ;
*/ m$,cH>E
public Page getPage(){ pXve02b1B
return page; TNJ<!6
} Z^{+,$H@
c%ZeX%p
/** sw [oQ!f
* @param content m"<4\;GK
* The content to set. Q,D0kS P
*/ *X~B-a |nJ
public void setContent(List content){ c6t2Q6zV
this.content = content; #FEa 5
} ,.[.SU#V
stX'yya
/** d [)_sa
* @param page XO 0>t{G
* The page to set. V_Xy2<V
*/ S|~i>
publicvoid setPage(Page page){ /X@7ju;
this.page = page; aF,jJ}On
} RV(
w%g
} /.7$`d
9!5b2!JL
3aEt>x
ylkpYd
sP9 ^IP
2. 编写业务逻辑接口,并实现它(UserManager, 4Y`! bT`
Uc\|X;nkRk
UserManagerImpl) chKF6n
java代码: =*{K@p_
B"7$!C o
^Vl^,@
/*Created on 2005-7-15*/ `x2fp6
package com.adt.service; qnabw F
J'|=*#
import net.sf.hibernate.HibernateException;
DhY;pG,t
jAA'hA
import org.flyware.util.page.Page; kSLSxfR
Pbc`LN/s|
import com.adt.bo.Result; L.SDM z
9+]ZH.(YE
/** ;n3uV`\
* @author Joa sXSj OUI
*/ [Xs}FJ
publicinterface UserManager { WH{cJ7wCL
T^KCB\\<
public Result listUser(Page page)throws 2.^7?ok
qJsQb
HibernateException; .Ql;(Wyl
%T3j8fC{s
} hCU)W1q#
p#ZMABlE,P
:X3rd|;kc
4aj[5fhb-
t9-_a5>E\}
java代码: w~bG<kxP
zd?bHcW/h
$~
pr+Ei
/*Created on 2005-7-15*/ `Mo~EHso.
package com.adt.service.impl; r0~ 7v1rG
2Som0T<2
import java.util.List; L@C >-F|p
#cw!
&
import net.sf.hibernate.HibernateException; k\4g|Lya
@).WIs
import org.flyware.util.page.Page; JA}S{
import org.flyware.util.page.PageUtil; y&n1 Nj]^
sL!;hKK
import com.adt.bo.Result;
Nb#H@zm
import com.adt.dao.UserDAO; {Uik|
import com.adt.exception.ObjectNotFoundException; Gh>"s #+
import com.adt.service.UserManager; ;yRwoTc)Y
.a 'ETNY:>
/** _DNkdS
[[
* @author Joa `l
HKQwu
*/ XS}Zq4H
publicclass UserManagerImpl implements UserManager { <ol$-1l#9
/.pa
??u
private UserDAO userDAO; b|X>3(
y}(_SU
/** X;K8,A7`
* @param userDAO The userDAO to set. `77;MGg*
*/ v&t`5-e-A
publicvoid setUserDAO(UserDAO userDAO){ OhA^UP01-
this.userDAO = userDAO; /ChJ~g "
} jD&}}:Dj
G:E+s(x
/* (non-Javadoc) <[ g$N4
* @see com.adt.service.UserManager#listUser S+` !%hJ
}e&KO?x+
(org.flyware.util.page.Page) *>}McvtTw
*/ TzD:bKE&
public Result listUser(Page page)throws /u"
cl2|
#C;#$|d
HibernateException, ObjectNotFoundException { ?RrC~7~
int totalRecords = userDAO.getUserCount(); Z'*G'/*
if(totalRecords == 0) hq|jC
throw new ObjectNotFoundException (P]^8qc
Apw-7*/
("userNotExist"); 18[?dV
page = PageUtil.createPage(page, totalRecords); 30gZ_8C>}
List users = userDAO.getUserByPage(page); C%x(`S^/
returnnew Result(page, users); a=}">=]7
} x| ~D(zo
`Cb<KAaCH
} K8 Kz
ie$fMBIq
K'{ wncumQ
xX/Qoq (}i
1*c0\:BQ;z
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 TkoCyD9
% @^VrhS
询,接下来编写UserDAO的代码: } (GQDJp
3. UserDAO 和 UserDAOImpl: B?/12+sR
java代码: D6pEQdX`
i?P]}JENM
z-{"pI
/*Created on 2005-7-15*/ W~W?<%@
package com.adt.dao; *aSR KY
&CPe$'FYI
import java.util.List; Og%zf1)aZM
eAenkUBz6,
import org.flyware.util.page.Page; e\|E; l
-Z\UYt
import net.sf.hibernate.HibernateException; >.k@!*
Qh1Kl_a?Lv
/** eog,EP"a8Y
* @author Joa I5|S8d<
*/ BT*K,p
publicinterface UserDAO extends BaseDAO { 'nmYB:&!
*}Ae9
publicList getUserByName(String name)throws +Fy-~Mq
]i_):@
HibernateException; <R]Wy}2-
$F
/p8AraK
publicint getUserCount()throws HibernateException; Y
GcY2p<
!513rNO
publicList getUserByPage(Page page)throws JzS^9)&
EC\rh](d
1
HibernateException; v#AO\zYKd
T_;G))q'
} DrVbx
F4aJr%!\6S
Zj /H3,7
y(p:)Iv
"b+3 &i|
java代码: !Vod0j">
t g m{gR
Y9(i}uTi
/*Created on 2005-7-15*/ 0I AaPz/e
package com.adt.dao.impl; (WU~e!}
p%M(G#gOgP
import java.util.List; zs]>XO~Jg
0UAr}H.:
import org.flyware.util.page.Page; ph|2lLZ
ph$&f0A6Xc
import net.sf.hibernate.HibernateException; (x*2BEn|
import net.sf.hibernate.Query; 1>O0Iu
rj`.hXO
import com.adt.dao.UserDAO; uJAB)ti2I
v:;C|uE|
/** 9#=IrlV4
* @author Joa -QHzf&D?
*/ V[2<ha[n>
public class UserDAOImpl extends BaseDAOHibernateImpl 14)kKWG
<pa];k(IQL
implements UserDAO { *^$N$t/2
e715)_HD
/* (non-Javadoc) 66y ,{t
* @see com.adt.dao.UserDAO#getUserByName ?2bE=|
(UiH3Q9C]%
(java.lang.String) g5TLX&Bd
*/ d T-O8
publicList getUserByName(String name)throws 6`PGV+3j
{10+(Vl
HibernateException { Y&!McM!Jw
String querySentence = "FROM user in class P)o[p(
E4fvYV_ra
com.adt.po.User WHERE user.name=:name"; vXWESy
Query query = getSession().createQuery Dqo:X`<bT
qi5>GX^t]b
(querySentence); g_U*_5doA
query.setParameter("name", name); ]8j5Ou6#y
return query.list(); 1oVD Oo
} uC$4TnoQx.
{&AT}7
/* (non-Javadoc) xN~<<PIZ
* @see com.adt.dao.UserDAO#getUserCount() iF2IR{h
*/ C@:N5},]
publicint getUserCount()throws HibernateException { *{n,4d\..
int count = 0; fJN9+l
String querySentence = "SELECT count(*) FROM :~YyHX
ZI:d&~1i1
user in class com.adt.po.User"; %L,,
Query query = getSession().createQuery ,Y/>*,J
c\?/^xr'!}
(querySentence); Mh@ylp+q
count = ((Integer)query.iterate().next _:z;j{@4
}&^bR)=
()).intValue(); hFF&(t2{^
return count; 0~I)
/T
} }t{^*(
!7Q.w/|=
/* (non-Javadoc) ~#xs
`@{s
* @see com.adt.dao.UserDAO#getUserByPage ^K@GK
R5YtCw]i=
(org.flyware.util.page.Page) Q0cf]
*/ xuC6EK+
publicList getUserByPage(Page page)throws G`<1>%"F
78}%{7YY
HibernateException { wB0WR
String querySentence = "FROM user in class ^{,},
i
GTX&:5H\t
com.adt.po.User"; (IWd?,H,n
Query query = getSession().createQuery e@MCumc~+
X!'Xx8
(querySentence);
(Y?yGq/
query.setFirstResult(page.getBeginIndex()) M)It(K8R
.setMaxResults(page.getEveryPage()); 2FtEt+A+'
return query.list(); +\@\,{Ujy
} D}=i
tu
C]@B~X1H^
} PDiorW}]k
Ts *'f
(?=(eo<N
ku8Z;ONeH
rs
KE
至此,一个完整的分页程序完成。前台的只需要调用 A^jm<~
|[t=.dK%
userManager.listUser(page)即可得到一个Page对象和结果集对象 8&AorYw[
2+rao2
的综合体,而传入的参数page对象则可以由前台传入,如果用 "alO"x8t
W;*vcbP
webwork,甚至可以直接在配置文件中指定。 ' <jp.sZQ
?9M+fi
下面给出一个webwork调用示例: B,qZwc|
java代码: yD'h5)yu
T</gWW
cnO4NUDv
/*Created on 2005-6-17*/ y")>"8H
package com.adt.action.user; G&B}jj
X%qR6mMfT7
import java.util.List; x{w ?X.Nt
ph. :~n>z
import org.apache.commons.logging.Log; $BN+SD!
import org.apache.commons.logging.LogFactory; (9QRg;
import org.flyware.util.page.Page; ~w%+y
v\T1,Z@N^
import com.adt.bo.Result; \YyU5f7';
import com.adt.service.UserService; %=>xzP(z
import com.opensymphony.xwork.Action; U-:Z^+Y
YS6az0ie
/** MA QY/s~F
* @author Joa ^Rh ~+
*/ {:+^[rerj
publicclass ListUser implementsAction{ U/lra&P
Y'":OW#oN
privatestaticfinal Log logger = LogFactory.getLog DdW8~yI&
745PCC'FK
(ListUser.class); y9mZQq
|W[rywxx
private UserService userService; R9HS%O6b6
e/%YruzS
private Page page; rx)Q]
-B! TA0=oJ
privateList users; k18V4ATE]
vK/Z9wR*05
/* WWzns[$f
* (non-Javadoc) oMf h|B
* l$@lk?dc
* @see com.opensymphony.xwork.Action#execute() y$W3\`2q
*/ !0_Y@>2
publicString execute()throwsException{ q&x#S_!
Result result = userService.listUser(page); "lAS
<dq
page = result.getPage(); ~UFsi VpL
users = result.getContent(); kKO]q#9sO
return SUCCESS; 61 |xv_/
} B*Xh$R
QR8Q10
/** !y0
O['7
* @return Returns the page. b8Sl3F?-~
*/ jt*@,+e|
public Page getPage(){ Jx7^|A
return page; 'S>Jps@
} _JB3+0@
J?DyTs3Z
/** nQMN2j M
* @return Returns the users. -I<`!kH*
*/ ywBo9|%T
publicList getUsers(){ l;i
u`
return users; breVTY7 S
} DSa92:M}
Z0^do
/** >eI(M $
* @param page epe}^Pl
* The page to set. Q4 S8NqE
*/ +[qy HTcG
publicvoid setPage(Page page){ #{PNdINoU
this.page = page; cFo-NI2
} 1EB`6_>y
SesO$=y
/** J>&GP#7}
* @param users 4(]('[M
* The users to set. HX^
P9jXT
*/ =25"qJr
publicvoid setUsers(List users){ )Qp?LECrt
this.users = users; "[,XS`
} rZ7 Ihof
%&NK|M+n
/** ^hJ,1{o
* @param userService efm<bJB2
* The userService to set. 0cVXUTJ|W
*/ =$J2
publicvoid setUserService(UserService userService){ H|?`n
uiD
this.userService = userService; P@ u%{
} NmXTk+,L#
} oyY,uB.|
cgAcAcmY
}P#gXG
DO;
2)ZQ%
L"0L_G
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, Fh;(1X75I
'-_PO|}
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 ,y @3'~
R8)"M(u=l
么只需要: ;o=mL_[
java代码: $fO*229As
YFY)Z7fK
pe-d7Ou
P
<?xml version="1.0"?> -W,b*U
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ~heF0C_
bzS [X
1.0//EN" "http://www.opensymphony.com/xwork/xwork- _BV:i:z
s.R(3}/
1.0.dtd"> dE~ns
,+
wH.'EC
<xwork> 3&
$E
J(]nPwm=.-
<package name="user" extends="webwork- TgLlmU*qMU
8jk*N
interceptors"> &3efJ?8
_!ed.h.r:
<!-- The default interceptor stack name xUUp?]9y
C}Q2UK-:
--> 2I
<default-interceptor-ref 195(Kr<5$
$qqusa}`K
name="myDefaultWebStack"/> wl4yNC
S/|8'x{<
<action name="listUser" ]Yy
Sf
P!/8
class="com.adt.action.user.ListUser"> uQlV zN.?
<param Fk\xq`3'c
<|@9]>z
name="page.everyPage">10</param> _rv_-n]"o
<result ,&$Y2+
/(w5S',EL
name="success">/user/user_list.jsp</result> p#w,+)1!d
</action> "x)W3C%*S
$A,=z
</package> %9K@`v-
$uqlJG#`
</xwork> 7gkHKdJoMA
TBzM~y
^AN9m]P
_\6-]
R;%iu0
9/Ls3U?
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 P-C_sj A7
F&Gb[Q&a8
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。 ]KmYPrCl0
B4?P"|
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 K"D9. %7
>_o_&;=`v
Kt-@a%O0
<Aa%Uwpc
JQb]mU%?
我写的一个用于分页的类,用了泛型了,hoho KK?}`o
VC@o]t5
java代码: eP)RP6ON{
*QLbrR
q^s$4 q
package com.intokr.util; Ugn"w E
nsPM`dz/
import java.util.List; {_Y\Y
:2?du
/** c~V\,lcI
* 用于分页的类<br> ??F{Gli"C`
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #KIHq2:.4
* `c icjA@~
* @version 0.01 b#b#r
* @author cheng b% F|VG
*/ pJmn;XbME
public class Paginator<E> { \%)p7PNY
privateint count = 0; // 总记录数 ojaZC,}
privateint p = 1; // 页编号 B\Uj
privateint num = 20; // 每页的记录数 gP}M\3-O
privateList<E> results = null; // 结果 ,T]okN5uI
$I.'7
&h;
/** 5b&'gd^d
* 结果总数 30<^0J.1
*/ bV"0}|A~K
publicint getCount(){ :KQ<rLd
return count; uwbj`lpf
} ;y"DEFs,u
ykZ)`E]P`
publicvoid setCount(int count){ <v\|@@X
this.count = count; *StJ5c_kg2
} U@9n7F
6 R!0v8
/** uB%`Bx'OW
* 本结果所在的页码,从1开始 # RtrHm
* PKP(:3|
* @return Returns the pageNo. xd*kNY
*/ ]8RcZn
publicint getP(){ {h2D}F
return p; J~==<?j:
} 0j*8|{|
WPPmh~:
/** 6s6[sUf=l&
* if(p<=0) p=1 qLR)>$
* JLjx4B\
* @param p sV-9 xh)i
*/ LB>!%Vx
publicvoid setP(int p){ ~
^K[pA ?
if(p <= 0) \=.iM?T
p = 1; "2 Kh2[K
this.p = p; _ZJP]5
} s)}C&T$Y.
O%)w!0
/** )#1@@\< ^T
* 每页记录数量 @6\8&(|
*/ -Z @cj
publicint getNum(){ ]g:VvTJ;?
return num; -gzk,ymp
} mX
%;
_Ab|<!a/R
/** 2 Y%$6NX
* if(num<1) num=1 nH;^$b'LZ
*/ `S%pD.g,2
publicvoid setNum(int num){ f@Db._E
if(num < 1) 'E6)6N
num = 1; myH#.$=A
this.num = num; !bQ5CB
} zE<}_nA
MgA6/k
/** GR/
p%Y(
* 获得总页数 90Q}9T\
*/ hEDj"`Px
publicint getPageNum(){ 7Ij'!@no
return(count - 1) / num + 1; pZXva9bE
} qPWYY
#\fApRL
/** iMF:~H-Yq#
* 获得本页的开始编号,为 (p-1)*num+1 ^"l4
*/ I"r*p?
publicint getStart(){ uA,K}sNRZ
return(p - 1) * num + 1; dqcfs/XhP
} s@0#w*N
k
kY*OA
/** gVA$P
* @return Returns the results. KN5.2pp
*/ {eS!cZJ
publicList<E> getResults(){ oveW )~4
return results; qL(Qmgd
} ^lf)9 `^U
s2q#D.f
public void setResults(List<E> results){ p5E|0p
this.results = results; +[:}<^p?cG
} !x[+rf
D/rKqPp|!
public String toString(){ {um~]
StringBuilder buff = new StringBuilder hmQD-E{Ab
_ u/N#*D
(); *ZAue.
buff.append("{"); #VtlXr>G
buff.append("count:").append(count); #k*e>d$
buff.append(",p:").append(p); fZ$8PMZv
buff.append(",nump:").append(num); F8.Fp[_tM
buff.append(",results:").append >AJtoJ=j
s<tdn[d
(results); yo3'\I
buff.append("}"); FK0nQ{uB"
return buff.toString(); RaKL KZn
} @32JMS<
yPKeatH]
} g?)9zJ9
S'lZ'H /
]hc.cj`\W&