Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 >M##q?.
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 AGO"),
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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 :>_oOn[ _
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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 \}Iq-Je
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分页支持类: CBpwtI>p
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java代码: ma<uXq
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package com.javaeye.common.util; ]ZW-`U MO
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import java.util.List; SXvflr] =m
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publicclass PaginationSupport { ~Je40vO[
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publicfinalstaticint PAGESIZE = 30; cq3Z}Cp
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privateint pageSize = PAGESIZE; W! Hn`T
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privateList items; {X_I>)Wg
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privateint totalCount; Q00v(6V46
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privateint[] indexes = newint[0]; `
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privateint startIndex = 0; >ZeARCf"f
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public PaginationSupport(List items, int Z5*(xony0
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totalCount){ xirq$sEl
setPageSize(PAGESIZE); L<B)BEE.
setTotalCount(totalCount); z}Us+>z+jc
setItems(items); #T{)y
setStartIndex(0); F+ RE
} b353+7"|
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public PaginationSupport(List items, int 2i
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totalCount, int startIndex){ SXO.|"M
setPageSize(PAGESIZE); I3'UrKKO
setTotalCount(totalCount); ZitmvcMk
setItems(items); ~ISY( &
setStartIndex(startIndex); :xbj&
l
} =YfzB!ld
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public PaginationSupport(List items, int FUJ<gqL
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totalCount, int pageSize, int startIndex){ $/@
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setPageSize(pageSize); !y>up+cRjl
setTotalCount(totalCount); 4i}nk
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setItems(items); q4G$I?4
setStartIndex(startIndex); X Z3fWcw[
} 6%:~.ZfN
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publicList getItems(){ P{:Z xli0
return items; w:iMrQeJg
} r ?<kWR?w
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publicvoid setItems(List items){ \&ZEIAe
this.items = items; ka ;=%*7T
} JRZp'Ln
U /~uu
publicint getPageSize(){ q8;MPXSG3
return pageSize; 4`fV_H.8
} k'PvQl"I
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publicvoid setPageSize(int pageSize){ Sl'$w4s
this.pageSize = pageSize; ~-uf%=
} ^6F, lS _t
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publicint getTotalCount(){ i_l{#*t
return totalCount; Gm9
} 9ZatlI,
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publicvoid setTotalCount(int totalCount){ fo`R=|L[
if(totalCount > 0){ , /jHhKW
this.totalCount = totalCount; 5JK'2J&
int count = totalCount / %g89eaEZ
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pageSize; 8faT@J'e;
if(totalCount % pageSize > 0) $<C",&
count++; iQT0%WaHl
indexes = newint[count]; }~ N\A
for(int i = 0; i < count; i++){ Ea'jAIFPpO
indexes = pageSize * \/gf_R_GN
bb\XZ~)F
i; 3 |LRb/|
} :D;pD l
}else{ q
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this.totalCount = 0; f\Hw Y)^>
} :A:7^jrhi
} ,O:p`"3`0=
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publicint[] getIndexes(){ ,Shzew+
return indexes; wq!9wk9
} $sg- P|Wo
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publicvoid setIndexes(int[] indexes){ _T~&kwe
this.indexes = indexes; VAUd^6Xdwx
} I>vU;xV\m
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publicint getStartIndex(){ u^c/1H:6
return startIndex; XeY[;}9
} {D|ST2:E
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publicvoid setStartIndex(int startIndex){ Q=vo5)t
if(totalCount <= 0) br
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this.startIndex = 0; ycki0&n3
elseif(startIndex >= totalCount) ,`!lZ|
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this.startIndex = indexes 02tN=}Cj)
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[indexes.length - 1]; *B{]
elseif(startIndex < 0) e Y^zs0
this.startIndex = 0; -%P}LaC<
else{ h6<i,1gQ1
this.startIndex = indexes ^`aw5 +S
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[startIndex / pageSize]; cXf/
} \-{$IC-L
} llh
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publicint getNextIndex(){ uTPAf^|
int nextIndex = getStartIndex() + :pz@'J
nnE'zk<"
pageSize; V=5*)i/
if(nextIndex >= totalCount) f\q5{#"z
return getStartIndex(); I8B0@ZtV
else G|-RscPe
return nextIndex; _h,_HW)G
} f#!nj]}#
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publicint getPreviousIndex(){ ].aFdy
int previousIndex = getStartIndex() - 0kls/^ 0,
$)PS#ND&
pageSize; |r?0!;bN0
if(previousIndex < 0) ,O-_Pv
return0; .m>Qlh
else gi5X,:[
return previousIndex; +F-Y^):
} ^-mW k?>
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} 9mv0} I
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抽象业务类 C!+PBk[9
java代码: tX1`/}``
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/** V lO^0r^z
* Created on 2005-7-12 }U5$~,*p
*/ QHUFS{G]
package com.javaeye.common.business; 'NfsAE
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import java.io.Serializable; F`(;@LO
import java.util.List; "cly99t
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import org.hibernate.Criteria; !;[cJbqnh
import org.hibernate.HibernateException; |JWYsqJ0U
import org.hibernate.Session; m?Cb^WgcF
import org.hibernate.criterion.DetachedCriteria; Oj_F1.
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import org.hibernate.criterion.Projections; DrAIQ7Jd
import pr4y*!|Y$
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org.springframework.orm.hibernate3.HibernateCallback; ,D(Bg9C
import q(hBqU W
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org.springframework.orm.hibernate3.support.HibernateDaoS \dE{[^.5
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upport; #r?[@aJ
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import com.javaeye.common.util.PaginationSupport; PU1YR;[Fe
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public abstract class AbstractManager extends 8'TIDu
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HibernateDaoSupport { fi ~@J`
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privateboolean cacheQueries = false; eX}aa0
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privateString queryCacheRegion; \Zx&J.D
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publicvoid setCacheQueries(boolean Ars*H,9>e
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cacheQueries){ s?->2gxhx
this.cacheQueries = cacheQueries; Y+vIU*O
} S# baOO
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publicvoid setQueryCacheRegion(String *kTp(*K/7`
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queryCacheRegion){ w,R6:*p5
this.queryCacheRegion = ?@FqlWz ,
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queryCacheRegion; V\r{6-%XiW
} r%X
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publicvoid save(finalObject entity){ l. l)w
getHibernateTemplate().save(entity); EowzEGq!a5
} _!Tjb^
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publicvoid persist(finalObject entity){ Cd]A1<6s
getHibernateTemplate().save(entity); a&)!zhVP
} gE=9K @
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publicvoid update(finalObject entity){ C|w<mryx
getHibernateTemplate().update(entity); H`URJ8k$Q
} 4/mz>eK"
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publicvoid delete(finalObject entity){ cwtlOg
getHibernateTemplate().delete(entity); (0`w.n
} Vmh$c*TE
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publicObject load(finalClass entity, 7w8UnPuM
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finalSerializable id){ s] ;P<
return getHibernateTemplate().load D2gyn-]\
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(entity, id); " Qyi/r41
} *f>\X[wN
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publicObject get(finalClass entity, W$;qhB
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finalSerializable id){ V,'_BUl+x
return getHibernateTemplate().get _j0xL{&&
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(entity, id); T:2f*!r
} 3k(tv U+eC
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publicList findAll(finalClass entity){ p$jAq~C
return getHibernateTemplate().find("from _JTK$\
(aSuxl.Dq
" + entity.getName()); "_dg$j`Y&&
} $Zw+"AA
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publicList findByNamedQuery(finalString m}oR*<.
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namedQuery){ GXQ%lQ
return getHibernateTemplate JhTr{8{
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().findByNamedQuery(namedQuery); {[Y7h}7
} jrz.n4Y`
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publicList findByNamedQuery(finalString query, 3^fwDt}
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finalObject parameter){ AL,7rYZG$
return getHibernateTemplate &HAu;u@
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().findByNamedQuery(query, parameter); dKU:\y
} N81M9#,["~
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publicList findByNamedQuery(finalString query, Kr1Y3[iNv
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finalObject[] parameters){ l Ib
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return getHibernateTemplate !]D`|HoW
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().findByNamedQuery(query, parameters); BOcD?rrZ0
} -KfK~P3PF
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publicList find(finalString query){ ElDeXLr'
return getHibernateTemplate().find j&Xx{ 4v
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(query); 33D2^Sf6"
} mD&I6F[s
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publicList find(finalString query, finalObject 74:~F)BP
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parameter){ $M!iQ"bb
return getHibernateTemplate().find BKb#\(95*
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(query, parameter); j3N d4#
} N|>JLZ>
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public PaginationSupport findPageByCriteria TecMQ0
KD
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(final DetachedCriteria detachedCriteria){ 6aHD?a o
return findPageByCriteria +/RR!vG,
t0@AfO.'1
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Jp}\@T.
} Ok{1{EmP
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public PaginationSupport findPageByCriteria La'6k
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(final DetachedCriteria detachedCriteria, finalint A?}[rM
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startIndex){ Cj`~ntMN
return findPageByCriteria +WMXd.iN,
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(detachedCriteria, PaginationSupport.PAGESIZE, gC iM\Qx
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startIndex); }
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} jn(!6\n"
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public PaginationSupport findPageByCriteria YaC[S^p
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(final DetachedCriteria detachedCriteria, finalint 'bSWJ/;p)
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pageSize, ry=8Oq&[~
finalint startIndex){ L*,h=#x(
return(PaginationSupport) H&p:
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getHibernateTemplate().execute(new HibernateCallback(){ A/UO cl+N
publicObject doInHibernate dhnX\/
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(Session session)throws HibernateException { %g@\SR.
Criteria criteria = DC1.f(cdR
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detachedCriteria.getExecutableCriteria(session); |?Edk7`
int totalCount = "a~r'+'<
6k>5+ -&_
((Integer) criteria.setProjection(Projections.rowCount ^--R#$X
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()).uniqueResult()).intValue(); Y%0rji
criteria.setProjection ")vtS}Ekt
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(null); U5~aG!E
List items = 6S3D#SY
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criteria.setFirstResult(startIndex).setMaxResults 32SkxcfrCK
)AR-b8..o
(pageSize).list(); :A @f[Y'9
PaginationSupport ps = )[ZXPD
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new PaginationSupport(items, totalCount, pageSize, `L7^f!
f+s)A(?3
startIndex); #V]8FW
return ps; |gu@b~8
} ]u$tKC
}, true); W'"?5} (
} )uo".n|n~B
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public List findAllByCriteria(final fiA8W
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DetachedCriteria detachedCriteria){ wEX<[#a-
return(List) getHibernateTemplate o
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().execute(new HibernateCallback(){ G!I5Er0pdy
publicObject doInHibernate G7+ {O7
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(Session session)throws HibernateException { G/},lUzLg
Criteria criteria = O-W[^r2e
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detachedCriteria.getExecutableCriteria(session); "9aFA(H6w
return criteria.list(); er-0i L@
} Vjt7X"_/
}, true); tx9%.)M:n
} tKLeq(
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public int getCountByCriteria(final ILH[q>
8N9,HNBT$
DetachedCriteria detachedCriteria){ mk!8>XvM
Integer count = (Integer) N}7b^0k
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getHibernateTemplate().execute(new HibernateCallback(){ u?MhK#Mr
publicObject doInHibernate Hf_
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sn^ 3xAF
(Session session)throws HibernateException { 85[
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Criteria criteria = ~Y*.cGA
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detachedCriteria.getExecutableCriteria(session); c7@/<*E+
return kv2o.q
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criteria.setProjection(Projections.rowCount \I4Uj.'>\
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()).uniqueResult(); CPcUB4a%#
} %@)q=*=y
}, true); ~'0n
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return count.intValue(); 8$47Y2r@
} 4]0:zS*O
} k{F6WQ7
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用户在web层构造查询条件detachedCriteria,和可选的 P{`fav
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 iWr
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PaginationSupport的实例ps。 Rc4=zimr+
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ps.getItems()得到已分页好的结果集 =+T0[|gc(r
ps.getIndexes()得到分页索引的数组 ,98 F
ps.getTotalCount()得到总结果数 o_Y?s+~i[/
ps.getStartIndex()当前分页索引 VZ`YbY
ps.getNextIndex()下一页索引 I/A%3i=H
ps.getPreviousIndex()上一页索引 g5Io=e@s
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Nr,I`x\N
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 )y:))\>
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一下代码重构了。 bZfq?
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我把原本我的做法也提供出来供大家讨论吧: bVN?7D(
_]Ob)RUVH
首先,为了实现分页查询,我封装了一个Page类: qyKR]%yzi
java代码: =+DhLH}8
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/*Created on 2005-4-14*/ 7iM@BeIf
package org.flyware.util.page; BLqK5~
<^KW7M}w*c
/** _G<Wq`0w)
* @author Joa G}NqVbZ9]
* ><S2o%u~
*/ 5pY|RV6:
publicclass Page { DQV9=
&1yErGXC
/** imply if the page has previous page */ E
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privateboolean hasPrePage; -p7
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/** imply if the page has next page */ Da6l=M
privateboolean hasNextPage; |)%H_TXTy
46 \!W(O~y
/** the number of every page */ '4~I%Z7L
privateint everyPage; a"g\f{v0AR
FS @55mQ
/** the total page number */ @t$yg$Q?[
privateint totalPage; gPd,
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/** the number of current page */ *tR'K#:&g!
privateint currentPage; ?/sn"~"
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/** the begin index of the records by the current })(robBkA
!-%%94 Q
query */ *nHMQ/uf
privateint beginIndex; FoZI0p?L)9
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/** The default constructor */ I|;zGmg#k
public Page(){ F,pKt.x
la 0:jO5
} IFa~`Gf [
xy&*s\=:
/** construct the page by everyPage wzoT!-_X
* @param everyPage Rd]<591
* */ NzM ,0q
public Page(int everyPage){ L|-|DOgw
this.everyPage = everyPage; 3X ',L*f
} Uy)pEEu
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/** The whole constructor */ 2*
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public Page(boolean hasPrePage, boolean hasNextPage, D88IU9V&n
r[7*1'.p
,->5 sJ{U
int everyPage, int totalPage, #NL'r99D/o
int currentPage, int beginIndex){ G6x'Myg I
this.hasPrePage = hasPrePage; &l_}yf"v
this.hasNextPage = hasNextPage; 4,Uqcw?!F'
this.everyPage = everyPage; 9}fez)m:g0
this.totalPage = totalPage; [4dX[
this.currentPage = currentPage; ? `kZ 6$
this.beginIndex = beginIndex; ;}ThBb3
} z" ?WT$
]EQ*!
/** o:4#AkS
* @return _E6N*ORV
* Returns the beginIndex. zq ?xY`E
*/ 8$X3 J[_j
publicint getBeginIndex(){ /?TR_>
return beginIndex; DeT$4c*:[
} ,TB$D]u8
M&9urOa`
/** Au(oKs<
* @param beginIndex wPcEvGBN=
* The beginIndex to set. 7xG~4N<)]
*/ }&6:0l$4!
publicvoid setBeginIndex(int beginIndex){ %AWc`D
this.beginIndex = beginIndex; mZM7 4!4X
} ]TcQGW@'
[io|qLr}\
/** :B7U),T
* @return #!#s7^%K&
* Returns the currentPage. @+y,E-YTdV
*/ m] -cRf)9
publicint getCurrentPage(){ 3r,Kt&2$
return currentPage; V 7ZGT
} SdnO#J}{
BD^1V(
I/
/** 2vsV:LS.
* @param currentPage /?z3*x
* The currentPage to set. 9 v8^uPA
*/ $ye>;Ek
publicvoid setCurrentPage(int currentPage){ AUIp
vd
this.currentPage = currentPage; ! gfd!R
} qTMY]=(
Y
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/** E8p,l>6(f
* @return Mk+G(4p
* Returns the everyPage. Unb3
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*/ rQ U6*f
publicint getEveryPage(){ 9ZY,T]ym?
return everyPage; M#m;jJqON
} N0NFgW;
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/** x#R6Ez7
* @param everyPage Qj(ppep\U"
* The everyPage to set. G\V*j$}!
*/ &,{YfAxQ`
publicvoid setEveryPage(int everyPage){ {[L('MH2|
this.everyPage = everyPage; \ a(ce?C
} B_b5&M@
[8[<4~{
/** Y#=MN~##t
* @return T5.^
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* Returns the hasNextPage. >V]9<*c
*/ ,j.bdlI#
publicboolean getHasNextPage(){ jcBZ#|B7;
return hasNextPage; n5IQKYrg
} /m 7~-~$V
Z{yH:{Vk
/** 0\@oqw]6hv
* @param hasNextPage ?N!kYTR%}
* The hasNextPage to set. ~#}T|
*/ b`=g#B|
publicvoid setHasNextPage(boolean hasNextPage){ 6qT-
this.hasNextPage = hasNextPage; rK:cUW0]X
} -%^'x&e
pv-c>8Wb6
/** DL!%Np?`
* @return 2' ^7G@%
* Returns the hasPrePage. K,%CE
].
*/ ={N1j<%fh
publicboolean getHasPrePage(){ \^RKb-6n
return hasPrePage; UF*R1{
} P~iZae
',LC!^:~Nw
/** ?#z<<FR
* @param hasPrePage <1<xSr
* The hasPrePage to set. 6DgdS5GhT_
*/ oVPr`]
publicvoid setHasPrePage(boolean hasPrePage){ 4neO$^i8J
this.hasPrePage = hasPrePage; u*,>$(-u
} )58~2vR
CA5`uh
/** `+>K)5hrR
* @return Returns the totalPage. 2+~gZxHq
* :Q@/F;Z?
*/ uLPBl~Y
publicint getTotalPage(){ 5/7(>ivn
return totalPage; mw;4/
/R
} 0(:SEiz6s
zR]!g|;f
/** aW{5m@p{"
* @param totalPage x-%RRm<V
* The totalPage to set. ftl?x'P%
*/ M6Np!0G
publicvoid setTotalPage(int totalPage){ e"NP]_vh,
this.totalPage = totalPage; #Nco|v
} `.3@Ki~$#
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} .Y^cs+-o
JPng !tvR
8UqH"^9.Q7
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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 ,-8-Y>[
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个PageUtil,负责对Page对象进行构造: HTGLFY(&
java代码: !U1
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/*Created on 2005-4-14*/ U,;796h
package org.flyware.util.page; 4nh=Dq[
" r o'?
import org.apache.commons.logging.Log; 1
ptyiy
import org.apache.commons.logging.LogFactory; [0]A-#J
ZILJXX4
/** "* F`,I3
* @author Joa >0<n%V#s:r
* 5Pn.c!
*/
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publicclass PageUtil { A8Fe@$<#8
Vdd
privatestaticfinal Log logger = LogFactory.getLog xdM'v{N#m
LbRQjwc]W
(PageUtil.class); HG?+b
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/** .SER,],P
* Use the origin page to create a new page C c:<F_UI
* @param page m;MJ{"@A'
* @param totalRecords Z${eDl6i
* @return [YHtBM:y
*/ (=Kv1
H aD
publicstatic Page createPage(Page page, int o.0tD
6kdbbGO-
totalRecords){ F4==a8
return createPage(page.getEveryPage(), f(~N+2}
X~D[CwA|`
page.getCurrentPage(), totalRecords); $8%"bR;Hu
} Mb 4"bDBsl
p^RX<L/\=_
/** !|H,g wqU
* the basic page utils not including exception =&$z
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c3g`k"3*`
handler ?Y,^Moc:
* @param everyPage 'xxM0Kn`
* @param currentPage Z_m<x!
* @param totalRecords YI,t{Wy
* @return page 62zu;p9m
*/ m}s.a.x
publicstatic Page createPage(int everyPage, int Rk3
bZvj3
AguE)I&m
currentPage, int totalRecords){ /[\g8U{5B}
everyPage = getEveryPage(everyPage); 1(IZ,*i
currentPage = getCurrentPage(currentPage); T>rmm7F
int beginIndex = getBeginIndex(everyPage, V@#oQi*
PDuBf&/e
currentPage); %
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int totalPage = getTotalPage(everyPage, ~o"=4q`>
8{2
totalRecords); o9"?z
boolean hasNextPage = hasNextPage(currentPage, U{M3QOF
d9;&Y?fp
totalPage); x0(bM g>7
boolean hasPrePage = hasPrePage(currentPage); 2(@2z[eKr
nv@z;#&
returnnew Page(hasPrePage, hasNextPage, k)S1Z s~G
everyPage, totalPage, 0
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currentPage, L#byYB;E{
T[k$ [
beginIndex); |y eQz
} 0h*Le
1Ng.Ukb
privatestaticint getEveryPage(int everyPage){ .
c+m(Pk
return everyPage == 0 ? 10 : everyPage; 0ck3II
} rVNx2
b2UDP W
privatestaticint getCurrentPage(int currentPage){ YxJQ^D`
return currentPage == 0 ? 1 : currentPage; 9AX}V6\+
} n2B%}LLa
1?FG3X 5
privatestaticint getBeginIndex(int everyPage, int DMG~56cTO,
/ta}12Z
currentPage){ A%W]XEa<
return(currentPage - 1) * everyPage; )PP yJ@M
} :QGo
-,6-
tSJ#
privatestaticint getTotalPage(int everyPage, int W?.469yy
7UMZs7L$
totalRecords){ aM;SE9/U
int totalPage = 0; e>Z&0lV:
nWIZ0Nde'
if(totalRecords % everyPage == 0) D`a6D
totalPage = totalRecords / everyPage; }]o8}$&(
else Nbd4>M<
totalPage = totalRecords / everyPage + 1 ; y&,|+h
$e7%>*?m
return totalPage; BKg8p]`+
} .s*N1
U?h
F8?2+w@P
privatestaticboolean hasPrePage(int currentPage){ l1DJ<I2
return currentPage == 1 ? false : true; g&xj(SMj-$
} @9HRGxJ=}
OVi<d
privatestaticboolean hasNextPage(int currentPage, Ul_Zn
Ol RXgJ
int totalPage){ 4@{cK|
return currentPage == totalPage || totalPage == d/Q#Z
rz%~=Ca2j
0 ? false : true; :C} I6v=
} lK=Is
v+
u_^mN9h
IRm}?hHf
} <@;}q^`
|gO7`F2
T(?w}i
lfHN_fE>Mq
7s?#y=M
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 7! >0
z!3=.D
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 Qy" Jt ]O
&S{r;N5u
做法如下:
,XEIg
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 *gwlW/%Fz
9AVj/?kmU
的信息,和一个结果集List: MrHJ)x"hy
java代码: Pl:4`oY3
M=Ze)X\E*'
DlUKhbo$g
/*Created on 2005-6-13*/ Q`9c/vPU
package com.adt.bo; q8d](MaX
Ow/,pC >V
import java.util.List; +fXwbZ?p
f-|?He4O]
import org.flyware.util.page.Page; KBB)xez8
e^O:I
/** `&D#P%
* @author Joa RBrb7D{
*/ =Q(J!f
publicclass Result { !~vK[G(R
PG63{
private Page page; i;1pw_K
@FN|=?8%
private List content; nKm#
kb
a*5KUj6/TL
/** }9"''Z
* The default constructor )&1v[]%S
*/ $^iio@SW{
public Result(){ w UxFE=ia
super(); q*
R}yt5
} x8@ 4lxj
+ kKanm[!v
/** n\((#<&
* The constructor using fields v@%4i~N
* ~x,_A>a
* @param page uM`i!7}
* @param content jlj ge=#c2
*/ 66pjWS
{X
public Result(Page page, List content){ Pjs=n7
this.page = page; (SRY(q
this.content = content; 2V)+ba|+
} VEh9N
lwf4ke
/** ^_ch%3}Im
* @return Returns the content. @bA5uY!
*/ $@'BB=i
publicList getContent(){ X3}eq|r9
return content; cOV9g)7^O
} O"'xAPQW
v'S]g^
/** &K0b3AWc
* @return Returns the page. `CVkjLiy
*/ &'>m;W
public Page getPage(){ <8b1OdA
return page; (U&
} -SM_JR3<
$$m0mK
/** |)!f".`
* @param content z+yq%O
* The content to set. ,kJ7c;:i
*/ >O\+ 9T@
public void setContent(List content){ +u
Iq]tqe
this.content = content; kC. !cPd
} FB?~:7+'
=Mx"+/Yo*
/** m*]`/:/X[
* @param page 1@p,
* The page to set. $b|LZE\bU.
*/ + kMj|()>\
publicvoid setPage(Page page){ :u,.(INB
this.page = page; D:Q#%wJ
} Vq+7 /+2"
} R)66qRf
^Ye(b7Gd
Br9j)1;
m&gd<rt/
3l<qcKKc
2. 编写业务逻辑接口,并实现它(UserManager, ?\8aT"o
kaCN^yQ
UserManagerImpl) Ge`7`D>L
java代码: wL8ji>"
$L= Dky7
`*vO8v
/*Created on 2005-7-15*/ .JLJ(WM
package com.adt.service; *gwaW!=
44*#qLN
import net.sf.hibernate.HibernateException; @6G)(NGD
OY{fxBb
import org.flyware.util.page.Page; ;"nO'wN:h
>"2jCR$/
import com.adt.bo.Result; 7.Y;nem:(
HZAT_
/** 'l^Bb#)"
* @author Joa t?>}0\1
*/ +H3~Infr4f
publicinterface UserManager { `;}`>!8j
A:(|"<lA
public Result listUser(Page page)throws Vbv^@Kp
89:nF#
HibernateException; cIw X sx
0E26J@jcZ7
} ="$w8iRU
A.r7 ks
)<V!lsUx'-
&Gh,ROo4
mj'~-$5T
java代码: h7+"*fN
Vx<{cHQQ
;9j ]P56
/*Created on 2005-7-15*/ +=J$:/&U
package com.adt.service.impl; Em&3g
5Hu[*
import java.util.List; anW['!T9{s
~Yd[&vpQ
import net.sf.hibernate.HibernateException; /FN:yCf
vE)N6Ss
import org.flyware.util.page.Page; 3q/Us0jr
import org.flyware.util.page.PageUtil; l{7}3Am6
x >a h,
import com.adt.bo.Result; {nmu(EP
import com.adt.dao.UserDAO; G{: B'08
import com.adt.exception.ObjectNotFoundException; $Xwk8<
import com.adt.service.UserManager; (@}^ 3jpT
z~h?"'
/** =Oy& f:s
* @author Joa ?Vg~7Eu0
*/ _5 SvZ;4
publicclass UserManagerImpl implements UserManager { 7310'wc
E9\"@wu[d
private UserDAO userDAO; #-YbZ
?-c|c_|$
/** vy~6]hH
* @param userDAO The userDAO to set. q+9^rQ
*/ x,^-a
publicvoid setUserDAO(UserDAO userDAO){ ZOfv\(iJ;
this.userDAO = userDAO; fC'u-m?!Q'
} sX6\AYF1M
y<6Sl6l*
/* (non-Javadoc) ^4`x:6m
* @see com.adt.service.UserManager#listUser p'LLzc##
g
sm%4>sc
(org.flyware.util.page.Page) R8[VD iM6E
*/ 0 8L;u7u
public Result listUser(Page page)throws tkV[^OeU>
#D_Ti%.^}
HibernateException, ObjectNotFoundException { T2rwK2
int totalRecords = userDAO.getUserCount(); `>\
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if(totalRecords == 0) _:\rB
throw new ObjectNotFoundException VL*5
dsw^$R}
("userNotExist"); E&J<qTH9
page = PageUtil.createPage(page, totalRecords); G)~>d/
List users = userDAO.getUserByPage(page); wm#(\dj
returnnew Result(page, users);
6xx.Z3v
} g"sb0d9
uH$hMg
} ?H8w;Csq-
]uFJ~:R
tiGH#~?
pHR`%2!"t
\
R}I4'
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 $DH/
U $#^ e
询,接下来编写UserDAO的代码: 2#$7!`6K
3. UserDAO 和 UserDAOImpl:
*1v3x:pQ'
java代码: s@~3L
-}TP)/!,*
[cDDZ+6
/*Created on 2005-7-15*/ (zsmJe
package com.adt.dao; aW:*!d#
@{qcu\sZ
import java.util.List; H%n/;DW
j6^.Q/{^
import org.flyware.util.page.Page; ^kK")+K
pWzYC@_W
import net.sf.hibernate.HibernateException; sB:e:PK
XC6 |<pru
/** I;jH'._k#
* @author Joa br88b`L
*/ P}AwE,&Q
publicinterface UserDAO extends BaseDAO { JGq9RB]D$
)Mq4p'*A[
publicList getUserByName(String name)throws w$$pTk|&n
"d/54PKWx
HibernateException; T#rUbi>""
}6LcimQyK
publicint getUserCount()throws HibernateException; ZWyf.VJ
]gHrqi%
publicList getUserByPage(Page page)throws dj084q7
H)TKk%`7
HibernateException; "=]'"'B:
JqLPJUr
} =S54p(>
7mnO60Z8N
SKf;Fe
^K`PYai
*9KT@"v
java代码: I@N/Y{y#
w@P86'< v
-GL.8"c[
/*Created on 2005-7-15*/ .vmCKZ
package com.adt.dao.impl; ^&F.T-( A
g[b;1$
import java.util.List; pPs TgGai
`Q+O#l?
import org.flyware.util.page.Page; hHMp=8J7
h{yh}04P1
import net.sf.hibernate.HibernateException; )sIzBC
import net.sf.hibernate.Query; {nZP4jze
zwUZ*Se
import com.adt.dao.UserDAO; %QDAog
}}Q h_(
/**
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* @author Joa wD
*/ %j0c|u
public class UserDAOImpl extends BaseDAOHibernateImpl agoMsxI9
F$v ^S+Ch
implements UserDAO { g>ke;SH%KY
'U@Ep
/* (non-Javadoc) \RVfgfe
* @see com.adt.dao.UserDAO#getUserByName )@B!
W:f )#'
(java.lang.String) Tpnwwx[]:|
*/ |&S^L}V.C
publicList getUserByName(String name)throws Ei,dO;&
=*(_sW6;
HibernateException { Xhyc2DKa_
String querySentence = "FROM user in class 6a]Qg99\
FzsW^u+
com.adt.po.User WHERE user.name=:name"; h/aG."U
Query query = getSession().createQuery G^P9_Sw]d3
:gkn`z
(querySentence); rIv#YqT
query.setParameter("name", name); Ka{QjW!%d<
return query.list(); v>hc\H1P
} NCkrf]*F-
*bcemH8f
/* (non-Javadoc) [A uA<
* @see com.adt.dao.UserDAO#getUserCount() X|TGM
*/ SX?hu|g_r
publicint getUserCount()throws HibernateException { `sdbo](76
int count = 0; U z)G Y
String querySentence = "SELECT count(*) FROM 0rDQJCm
<aMihT)dd
user in class com.adt.po.User"; yaC_r-%U&
Query query = getSession().createQuery ->'q
'}Jq(ah(
(querySentence); ;M#D*<ucI:
count = ((Integer)query.iterate().next noWwX
gU@.IOg
()).intValue(); 8(6mH'^y
return count; n?^X/R.22
} vO;:~
"8[Vb#=*e
/* (non-Javadoc) Ip,0C8T`Q
* @see com.adt.dao.UserDAO#getUserByPage u"q!p5P%q
vf<Tq
(org.flyware.util.page.Page) AIQ]lQ(
*/ (j)>npOd9
publicList getUserByPage(Page page)throws / vzwokH
rYyEs
I#qo
HibernateException { nza^<DlS
String querySentence = "FROM user in class SP|Dz,o
V+y:!t`
com.adt.po.User"; wqn}t]
Query query = getSession().createQuery wGpw+O
y?s#pSX;N
(querySentence); l0wvWv*k
query.setFirstResult(page.getBeginIndex()) f;W>:`'
.setMaxResults(page.getEveryPage()); BjUz"69
return query.list(); y-7$HWn
} KMkX0+Ao
~o/e0
} 8+~|!)a
ZnB|vfL?
x6~`{N1N
M
p~u11rH
~u80v h'
至此,一个完整的分页程序完成。前台的只需要调用 [~rBnzb
j0K}nS\ P
userManager.listUser(page)即可得到一个Page对象和结果集对象 '"Dgov$q
dLu3C-.(
的综合体,而传入的参数page对象则可以由前台传入,如果用 6EX8,4c\
|)R{(AK-
webwork,甚至可以直接在配置文件中指定。 DO=zxdTI!
GmLKg >%
下面给出一个webwork调用示例: WXE{uGc
java代码: DvXbbhp
Zh.9j7
>p
x42m+5/
/*Created on 2005-6-17*/ DU[vLe|Z
package com.adt.action.user; @y\M8C8
J3=^+/g
import java.util.List; \Mod4tQ
y>m=A41:g
import org.apache.commons.logging.Log;
XS"lR |
import org.apache.commons.logging.LogFactory; yu62$d
import org.flyware.util.page.Page; c_bIadE{
(A8X|Y
import com.adt.bo.Result; `_&7-;)i*\
import com.adt.service.UserService; O!\\m0\e
import com.opensymphony.xwork.Action; {-Y% wM8<i
4qEeN-6h
/** GCPSe A~cx
* @author Joa HveOG$pT
*/ DJhCe==$v
publicclass ListUser implementsAction{ IE9A _u*
xk5Z&z
privatestaticfinal Log logger = LogFactory.getLog /7<l`RSr
KrT+Svm
(ListUser.class); l<RztzUw
(f|3(u'e?
private UserService userService; pVm'XP
as6YjE.Yy
private Page page;
fg1["{\
snyg
privateList users; vSy#[9}
[Y]\sF;J
/* y"SVZ} ;|
* (non-Javadoc) h"G#} C]
* u($y<Q)=
* @see com.opensymphony.xwork.Action#execute() $n?@zd@53
*/ J Covk1
publicString execute()throwsException{ }@:vq8%Q
Result result = userService.listUser(page); NrdbXPHceN
page = result.getPage(); .DSmy\FI5
users = result.getContent(); {` Lem
return SUCCESS; cvvba 60
} W[Ro)
xTW$9>@\m
/** Y_49UtJIg
* @return Returns the page. f?1?$Sp/W
*/ H)5v X+9D
public Page getPage(){ rOu7r 4
return page; bytAdS$3
} |};P"&
{1V~`1(w
/** C.
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* @return Returns the users. Zg/ra1n
*/ 'J&$L c
publicList getUsers(){ n`krK"Ii
return users; d&QB?yLd
} J!,<NlP0K
-%lA=pS{Fq
/** 'Bp7LtG92
* @param page h$EH|9HAb
* The page to set. {WJ+6!v
*/ c_li.]P
publicvoid setPage(Page page){ \ueo^p]_?
this.page = page; pAo5c4y!4
} c} GH|i
gSP]& _9j
/** J]A!>|Ic
* @param users -Fe))Y'=
* The users to set. E}d@0C:
*/ {re<S<j&
publicvoid setUsers(List users){ lV-b
this.users = users; `r:n[N=Y&
} {f\/2k3
kqfO3{-;{:
/** tB_GEt2M
* @param userService f\}fUg2
* The userService to set. $]eITyC`P
*/ Gvk)H$ni
publicvoid setUserService(UserService userService){ QQUYWC
this.userService = userService; %OeA"#
} <0r2m4z
} =G%k|
tk@
T-;
9H9 P'lx9
LwV4p6A
tO$/|B74Bz
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, h|tdK;)
)
N*,cTE
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 0L_JP9e
O9#8%p%
)
么只需要: _s/5oRHA
java代码: G'oMZb ({=
x roo_
`;yfSoY
<?xml version="1.0"?> yF-EHNNf
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork WleE$ ,
Nv@SpV'
1.0//EN" "http://www.opensymphony.com/xwork/xwork- )_eEM1
a7+w)]r
1.0.dtd"> 7cTDbc!E-
!=7(3<?
<xwork> ]_6w(>A@3#
gJE m
<package name="user" extends="webwork- J3OxM--8"
' XJ>;",[
interceptors"> SW!lSIk
ToWiXH)4
<!-- The default interceptor stack name @kCFc}
x{_:B
DY
--> Ib(q9!L
<default-interceptor-ref +>b~nK>M
DlHt#Ob7
name="myDefaultWebStack"/> W_:3Sj l'
i^9 ,. $<1
<action name="listUser" =]k0*\PS
>?/Pl"{b
class="com.adt.action.user.ListUser"> cn62:p]5
<param m5c?A+@fZ
%~eIx=s
name="page.everyPage">10</param> TUw+A6u:p
<result -?_#Yttu
V2As 5
name="success">/user/user_list.jsp</result> $on"@l%U
</action> kjVUG >e>
cZB?_[Cp
</package> }^!8I7J.
rucgav
</xwork> @ev"{dY
N`3q54_$
}HB>Zb5
3q'["SS
*$K_Tii
h$p]M^Z7
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 ,E8:!r)6
@d&(*9Y
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。 s!WGs_1@
_ebo
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 0, b.;r
vO>Fj
,sw|OYb
?A4zIJ\
N|JML
我写的一个用于分页的类,用了泛型了,hoho `fTH"l1zn
" Y%fk/v8
java代码: '%Cc!63t*
:1>h,NKC>
;a"g<v
package com.intokr.util; Yatd$`,hW
5`Q*
import java.util.List; kYbqb?
~quof>
/** 'q3<R%^Q
* 用于分页的类<br> _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> z$64Ep#
* +D7>$&BD
* @version 0.01 x*H,eY3
* @author cheng * {avx
*/ 8
5 L<
public class Paginator<E> { GkwdBy+
privateint count = 0; // 总记录数 JRti2Mu
privateint p = 1; // 页编号 R[#Np`z
privateint num = 20; // 每页的记录数 {5 V@O_*{
privateList<E> results = null; // 结果 |7Dc7p"D
QZwUv<*
/** rra|}l4Y
* 结果总数 EM2=g9y
*/ #VM+.75o1
publicint getCount(){ qQ&=Z`p!
return count; eELLnU{"
} d-X6yRjnj
8dPDs#Zl
publicvoid setCount(int count){ xG_LEk( zD
this.count = count; [TX1\*W
} mafnkQU
Z
"mqH
/** 6!39t
* 本结果所在的页码,从1开始 NUO#[7OK+x
* CvOji1
* @return Returns the pageNo. '6g;UOx^=
*/ lJHU1
gu
publicint getP(){ @\*`rl]
return p; .ZOG,h+8
} WswM5RN
_cc37[
/** 8'>yB
* if(p<=0) p=1 $^TxLv
* g5&ZXA
* @param p p>ba6BDJT
*/ 7MbV|gM}
publicvoid setP(int p){ i C)+5L#'
if(p <= 0) "]SA4Ud^
p = 1; rF^H\U:w
this.p = p; .8%&K0
} &0b\E73
pyw]ydB
/** (G6lr%d
* 每页记录数量 (Sv=R(_s
*/ ;W 3#q:
publicint getNum(){ H\%^n<]#
return num; "g5<j p
} y&n-8L_
*/_$' /qV
/** `w8Ejm?n
* if(num<1) num=1 G1
K@Ir<
*/ a
S;z
YD
publicvoid setNum(int num){ PIHix{YR
if(num < 1) u+;iR/
num = 1; 2tw3 =)
this.num = num; 9] L4`.HM
} o[aP+O Md
9oj#5Hq
/** rff_=(?i
* 获得总页数 SpO%nZ";g8
*/ 01n7ua*XX
publicint getPageNum(){ f8?hEa:js
return(count - 1) / num + 1; eK[9wEdn
} iBPIj;,
|4C5;"P c
/** <YM!K8hu$
* 获得本页的开始编号,为 (p-1)*num+1 P<CPA7K
*/ 2RU/oqmR
publicint getStart(){ ~v@.YJoZ4Z
return(p - 1) * num + 1; wzj:PS
} :u,Ji9
u
h1~/zM/`
/** 7](aPm8
* @return Returns the results. :IX_|8e ^
*/ ^\oMsU5(
publicList<E> getResults(){ &s8vmUt
return results; kp-`_sDg
} g_3Ozy
3dx.%~c
public void setResults(List<E> results){ WCYVon bg"
this.results = results; ?!.L#]23f
} % !>@m6JK
s7(1|}jh
public String toString(){ v=_Ds<6n
StringBuilder buff = new StringBuilder b:PzqMh{G
Bun^EJ)
(); e>UU/Ks
buff.append("{"); ~}_S]^br
buff.append("count:").append(count); Sa-" G`
buff.append(",p:").append(p); F AQx8P
buff.append(",nump:").append(num); k?}y@$[)
buff.append(",results:").append l h?[wc
D4T42L
(results); mhMTn*9
buff.append("}"); Doe:m#aNj
return buff.toString(); ~bqw !rz
} +3k.xP?QS
k5|GN Y6a
} {t*CSI
$3S`A]xO
9T\\hM)k