Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 n%r>W^2j
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 :7@[=n
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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 :b9#e g
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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 03?ADjO
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分页支持类: 5ncW
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java代码: iBWzxPv:z
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package com.javaeye.common.util; czw:xG!&
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import java.util.List; QeY+imM
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publicclass PaginationSupport { Ob%iZ.D|3<
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publicfinalstaticint PAGESIZE = 30; W'Gh:73'}
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privateint pageSize = PAGESIZE; wz+mFf
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privateList items; .}E<,T
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privateint totalCount; *3^7'^j<
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privateint[] indexes = newint[0]; ; 8VZsh
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privateint startIndex = 0; x~l"'qsK
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public PaginationSupport(List items, int H/f}tw
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totalCount){ dyqk[$(
setPageSize(PAGESIZE); .yzXw8~S
setTotalCount(totalCount); yR F+
setItems(items); vU/sQt8
setStartIndex(0); %to.'R
} )p!")
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public PaginationSupport(List items, int sS)tSt{C
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totalCount, int startIndex){ cLp9|y0r
setPageSize(PAGESIZE); )`=N+k]
setTotalCount(totalCount); q9zeN:><
setItems(items); 8}z PDs
setStartIndex(startIndex); VQ~eg wJL
} nP=/XiCj
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public PaginationSupport(List items, int F&/}x15
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totalCount, int pageSize, int startIndex){ G4F~V't
setPageSize(pageSize); wMH13i3
setTotalCount(totalCount); LGy!{c
setItems(items); ]~WIGl"g
setStartIndex(startIndex); ;?o"{mbb
} )sEAPIka
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publicList getItems(){ B*Q.EKD8s
return items; -mZ{.\9
} +w?1<Z
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publicvoid setItems(List items){ wZ8LY;
this.items = items; D@mqfi(x
} v^IMN3^W
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publicint getPageSize(){ piUfvw
return pageSize; Z*5]qh2r8
} v CR\lR+
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publicvoid setPageSize(int pageSize){ 7"_gX
this.pageSize = pageSize; H%c{ }F
} 2wh{[Q2f
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publicint getTotalCount(){ %hzNkyD)Y
return totalCount; VM
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} In4T`c?kQ
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publicvoid setTotalCount(int totalCount){ @l2AL9z$m>
if(totalCount > 0){ 2TC7${^9}J
this.totalCount = totalCount; y+[wlo&WC
int count = totalCount / Fx*IeIs(:~
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pageSize; g>R md[!/
if(totalCount % pageSize > 0) Ib4 8`
count++; E~!FEl;
indexes = newint[count]; Ie;}k;?-
for(int i = 0; i < count; i++){ >G+?X+9
indexes = pageSize * ?3i-wpzMp
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} Ts:pk
}else{ mE]W#?
this.totalCount = 0; xH8nn3U
} l>9ZAI\^
} 93y. u<,2;
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publicint[] getIndexes(){ !$5U\"M
return indexes; oM-@B'TK
} R=M${u<t
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publicvoid setIndexes(int[] indexes){ M+^+u 1QQ0
this.indexes = indexes; $NWI_F4
} VL<)d-
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publicint getStartIndex(){ j:,*Liz
return startIndex; \9BIRY`
} %P9Zx!i>
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publicvoid setStartIndex(int startIndex){ 'gE_xn7j
if(totalCount <= 0) fD|ox
this.startIndex = 0; @*l}2W
elseif(startIndex >= totalCount) T ,gMc
this.startIndex = indexes 5,qfr!hN,
}qXi;u))
[indexes.length - 1]; +B'9!t4 2
elseif(startIndex < 0) y?aOk-TaRA
this.startIndex = 0; uBs[[9je(
else{ 5kJ>pb$/
this.startIndex = indexes ZWVcCa3
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[startIndex / pageSize]; Xf9VW}`*8
} KFC zf_P!
} Fu m1w
}`
publicint getNextIndex(){
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int nextIndex = getStartIndex() + ipKkz
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pageSize; F1|4([-<]
if(nextIndex >= totalCount) Mi'eViH
return getStartIndex(); :ZU
else >1mCjP
return nextIndex; ^#%$?w>wI
} ZwF_hm=/[
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publicint getPreviousIndex(){ g[@]OsX
int previousIndex = getStartIndex() - |vWx[=`o
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pageSize; OBN]bvCJ
if(previousIndex < 0) }(TZ}* d
return0; 7,jh44(\=
else kS?!"zk>
return previousIndex; -_pI:K[
} /2?GRwU~P
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} jPA?0h
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抽象业务类 xp>ra2A
java代码: lgA9p
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/** D,1S-<
* Created on 2005-7-12 `<Zp!Hl(j
*/
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package com.javaeye.common.business; U4O F{
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import java.io.Serializable; M.!U;U<?
import java.util.List; o& $Fc8bH
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import org.hibernate.Criteria; aeE9dV~
import org.hibernate.HibernateException; i~.L{K
import org.hibernate.Session; A^
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import org.hibernate.criterion.DetachedCriteria; `2d ,=.X
import org.hibernate.criterion.Projections; oXV
import 0j4bu}@
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org.springframework.orm.hibernate3.HibernateCallback; zn>*^h0B
import d5+ (@HSR
:%)l*[
org.springframework.orm.hibernate3.support.HibernateDaoS y$#mk3(e~t
*)U=ZO6S
upport; `gD'q5.z;3
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import com.javaeye.common.util.PaginationSupport; [|xHXcW
x>;!`}x
public abstract class AbstractManager extends |AuN5|obI
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HibernateDaoSupport { \BbemCPAm
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privateboolean cacheQueries = false; qA#!3<
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privateString queryCacheRegion; 6}n>Nb;L"
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publicvoid setCacheQueries(boolean B@=+Fg DD
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cacheQueries){ 2zh?]if
this.cacheQueries = cacheQueries; ZVR0Kzu?Ra
} IdUMoLL?
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publicvoid setQueryCacheRegion(String "<t/*$42
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queryCacheRegion){ x'+lNlv
this.queryCacheRegion =
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queryCacheRegion; O (<Wn-
} |Xlc2?e
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publicvoid save(finalObject entity){ b-@6w(j
getHibernateTemplate().save(entity); 2N9
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} 's8NO
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publicvoid persist(finalObject entity){ 2d >kc2=*
getHibernateTemplate().save(entity); 8tK 8|t5+
} z0t6}E<VIR
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publicvoid update(finalObject entity){ -:Nowb
getHibernateTemplate().update(entity); MP-A^QT
} $C##S@
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publicvoid delete(finalObject entity){ TSt-#c4B
getHibernateTemplate().delete(entity); #)AcK|*y
} $h`?l$jC(@
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publicObject load(finalClass entity, R)?K+cJ%
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finalSerializable id){ K8$Hg:Ky-/
return getHibernateTemplate().load ^VR1whCrx
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(entity, id); 3/H^YM
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} '""qMRCm
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publicObject get(finalClass entity, 5H1SC8+B,
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finalSerializable id){ 3Wrl_V
return getHibernateTemplate().get =3?t%l;n
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(entity, id); %np b.C|+
} H'-Fv!l?
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publicList findAll(finalClass entity){ g2l|NI#c^
return getHibernateTemplate().find("from IJ3[6>/M0
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{a%:=`
" + entity.getName()); NIrK+uC.d
} BA' ($D>
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publicList findByNamedQuery(finalString dGAthbWJ
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namedQuery){ v_J\yW'K
return getHibernateTemplate 12])``9
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().findByNamedQuery(namedQuery); yHLclv
} <1.].A@b*
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publicList findByNamedQuery(finalString query, 0PE $n
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finalObject parameter){ }r3,
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return getHibernateTemplate -q[T0^eS
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().findByNamedQuery(query, parameter); b{)9?%_
} EMU~gwPR
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publicList findByNamedQuery(finalString query, zNuiBLxDs
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finalObject[] parameters){ Na=9ju
return getHibernateTemplate wxB?}
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().findByNamedQuery(query, parameters); EC&t+"=R
} #s{>v$F
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publicList find(finalString query){ "Y}f"X|
return getHibernateTemplate().find }OJ*o
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(query); -`n>q^A7e
} cEnkt=
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publicList find(finalString query, finalObject t }7hD
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parameter){ "
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return getHibernateTemplate().find H"WkZX
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(query, parameter); =xQ7:TB
} B~^MhX
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public PaginationSupport findPageByCriteria 25BW/23}e
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(final DetachedCriteria detachedCriteria){ #HWz.Wb
return findPageByCriteria #B8`qFpQC
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); vD D !.i
} YN?@ S
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public PaginationSupport findPageByCriteria lyI
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(final DetachedCriteria detachedCriteria, finalint O_K@\<;~
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startIndex){ Dx$74~2e
return findPageByCriteria `IOp*8
@g9j+DcU
(detachedCriteria, PaginationSupport.PAGESIZE, X_C9Z
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startIndex); 8A"[n>931
} leiED'
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public PaginationSupport findPageByCriteria bR?-B>EB
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, Qc;`nck
finalint startIndex){ 1,`-n5@J%n
return(PaginationSupport) Z{+h~?63
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getHibernateTemplate().execute(new HibernateCallback(){ ]/p0j$Tq$
publicObject doInHibernate VXQS~#dQj
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(Session session)throws HibernateException { Ox?LVRvxI
Criteria criteria = 6R%c+ok8i
@pQv}%
detachedCriteria.getExecutableCriteria(session); DX}EOxO,.
int totalCount = ~53E)ilB
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((Integer) criteria.setProjection(Projections.rowCount >ly= O
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()).uniqueResult()).intValue(); {-^>)
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criteria.setProjection C@pDX>~2=b
, Ot3N\%yn
(null); q\O'r[&V
List items = rr3NY$W
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criteria.setFirstResult(startIndex).setMaxResults 0MMY{@n
c1wgb8
(pageSize).list(); 00U8<~u
PaginationSupport ps = b6bmvHD
a: iIfdd4'
new PaginationSupport(items, totalCount, pageSize, &w2.b:HF
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startIndex); TmKO/N@}
return ps; _M:)x0("
} o1Mb HBb
}, true); 1)#<nk)I
} uWx/V+w
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public List findAllByCriteria(final $7TYix8=
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DetachedCriteria detachedCriteria){ &BG^:4b
return(List) getHibernateTemplate m{pL<
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().execute(new HibernateCallback(){ ]!YzbvoR
publicObject doInHibernate 3tnYK&
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(Session session)throws HibernateException { %E1~I\n:F
Criteria criteria = 5tP0dQYd
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detachedCriteria.getExecutableCriteria(session); ~Ufcy{x#
return criteria.list(); Yr-,0${m
} TQ=\l*R(A
}, true); cJ!wZT`
} 3WPMS/
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public int getCountByCriteria(final y>~=o9J_u
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DetachedCriteria detachedCriteria){ Mk@ _uPm
Integer count = (Integer) Ma-^o<{
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getHibernateTemplate().execute(new HibernateCallback(){ mWmDH74
publicObject doInHibernate !G\1$"T$
gQ?>%t]
(Session session)throws HibernateException { .4_~ku
Criteria criteria = S`0@fieOf
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detachedCriteria.getExecutableCriteria(session); N:L<ySJ7
return H@G7oK
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criteria.setProjection(Projections.rowCount @|-ydm0
/^#}
\<;
()).uniqueResult(); @Z3b^G[
} YXV![gw0
}, true); #\`6ZHW
return count.intValue(); H[-zQ#I9
} ,j&o H$mW
} v]VIUVd
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用户在web层构造查询条件detachedCriteria,和可选的 5fVdtJk7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 s?0r\ cc|:
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PaginationSupport的实例ps。 3l4k2
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ps.getItems()得到已分页好的结果集 c:=Z<0S;
ps.getIndexes()得到分页索引的数组 N.&)22<m9
ps.getTotalCount()得到总结果数 X-n'?=
ps.getStartIndex()当前分页索引 c?IIaj!
ps.getNextIndex()下一页索引 _ZR2?y-M
ps.getPreviousIndex()上一页索引 M.|hnGXN
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 4[Oy3.-c
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ky!'.3yoI
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一下代码重构了。 y# x]?%m
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我把原本我的做法也提供出来供大家讨论吧: A1YIPrav(
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首先,为了实现分页查询,我封装了一个Page类: D, 3x:nK
java代码: ^-=,q.[7
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/*Created on 2005-4-14*/ xY_/CR[,
package org.flyware.util.page; lIOLR-:4j
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/** L\n_q6n
* @author Joa {},GxrQm
* Y|1kE;
*/ F;MFw2G
publicclass Page { (?J&Ar0
_jnH!Mw
/** imply if the page has previous page */ @-u/('vpB
privateboolean hasPrePage; 5?2PUE,a
(<3'LhFII
/** imply if the page has next page */ V1"+4&R^T_
privateboolean hasNextPage; ]1p&*xX:Bj
DmD*,[rD
/** the number of every page */ .O lq_wuH
privateint everyPage; 3 YRhqp"E
#M8"b]oh6
/** the total page number */ JO1c9NyKr
privateint totalPage; C\EV$U,
Vl'|l)b4W
/** the number of current page */ t|%iW%m4
privateint currentPage; nc l-VN
)7J@A%u
/** the begin index of the records by the current c
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query */ m:
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privateint beginIndex; ZRcY; ?
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@gs
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/** The default constructor */ wRU pQ~=B2
public Page(){ J^1w& 40
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} dr:)+R
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/** construct the page by everyPage ~fQ#-ekzqk
* @param everyPage Ku&0bXP
* */ e9N 1xB
public Page(int everyPage){ %.<w8ag
this.everyPage = everyPage; w,JB`jS)/
} [}d
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/** The whole constructor */ ly6?jVJ
public Page(boolean hasPrePage, boolean hasNextPage, l<^#@S H
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int everyPage, int totalPage, ,/JrQWgD
int currentPage, int beginIndex){ ^=Up UB
this.hasPrePage = hasPrePage; v,1.n{!;
this.hasNextPage = hasNextPage; %n!s{5:F
this.everyPage = everyPage; k,b(MAiQ0
this.totalPage = totalPage; UGr7,+N&w
this.currentPage = currentPage; %,>> <8
this.beginIndex = beginIndex; 9k2HP]8=[{
} E
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/** T4qbyui{
* @return 8pt;''
* Returns the beginIndex. >^>
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*/ 0B1*N_.L@
publicint getBeginIndex(){ Wu:vO2aw8
return beginIndex; r~TiJ?8I
} * F~"4g
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/** JTl
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* @param beginIndex Qe]@`Vg
* The beginIndex to set. [*8wv^
*/ wdoA>a?q
publicvoid setBeginIndex(int beginIndex){ OFCkQEG=y>
this.beginIndex = beginIndex; >RE&>T^8
} g#5g0UP)V
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/** ]#))#-&1
* @return `;5UlkVZ5
* Returns the currentPage. QBY7ZT05Gt
*/ kzgHp,;R{
publicint getCurrentPage(){ 8uS1HE\%
return currentPage; qV8;;&8r
} \f0I:%-
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/** pShSKRg
* @param currentPage #qm<4]91
* The currentPage to set. :#c? `>uV
*/ m'oVqA&
publicvoid setCurrentPage(int currentPage){ -5kq9Dy\,
this.currentPage = currentPage; {Kd9}CDAZ
} mkrvWZjZX
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/** |PDuvv!.f
* @return (al7/EhY
* Returns the everyPage. G-bG}9vc]
*/ 9%kY8#%SV
publicint getEveryPage(){ pRUN[[L
return everyPage; aSXoYG0\
} -(Taj[;[
xgsD<3
/** G\Toi98d*
* @param everyPage k$k(g
* The everyPage to set. H&3VPag
*/ ~ E>D0o
publicvoid setEveryPage(int everyPage){ r"Pj,}$A
this.everyPage = everyPage; \TC&/'7}
} dUOjPq97
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/** +7N6]pK|"
* @return {B?%r[nW
* Returns the hasNextPage. @\u)k
*/ </:f-J%U/
publicboolean getHasNextPage(){ <s]K~ Vo
return hasNextPage; ')Ozz<{
} `Ft`8=(
DtXXfp@;
/** ]A9Vh
* @param hasNextPage ( F0.lDZ
* The hasNextPage to set. ElqHZ$a?
*/ `lN1u'(:
publicvoid setHasNextPage(boolean hasNextPage){ pWbzBgM?nU
this.hasNextPage = hasNextPage; xm/v:hl=
} @<W"$_r-
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/** &"Ua"H)
* @return ^dYFFKQ
* Returns the hasPrePage. UyD=x(li
*/ <4C`^p
publicboolean getHasPrePage(){ :NA cad
return hasPrePage; Q%o
} W(~G^Xu
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/** >F Z6\
* @param hasPrePage 7s<v06Wo
* The hasPrePage to set. gigDrf}
*/ f.V0uBDN
publicvoid setHasPrePage(boolean hasPrePage){ qaG%PH}a
this.hasPrePage = hasPrePage; P,_GTs3/G
} *)L%pH>`
D@>P%k$$s>
/** j%]i#iqF
* @return Returns the totalPage.
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* 9 n|H%AC
*/ PrDvRWM
publicint getTotalPage(){ &p=|z2 J
return totalPage; q<,?:g$k
} tG^Oj:
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/** H]}Iw5Z
* @param totalPage 8^c|9ow
* The totalPage to set. Vnv<]D
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*/ wvx
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publicvoid setTotalPage(int totalPage){ 75Jh(hd(
this.totalPage = totalPage; `r+e!o
} lv&<kYWY
+3]@0VM26;
} +%UXI$v
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9.#\GI ;
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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 "%qGcC8
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个PageUtil,负责对Page对象进行构造: L7q%u.nB1
java代码: i?4vdL8M
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/*Created on 2005-4-14*/ )q&uvfQ1(
package org.flyware.util.page; l: 1Zq_?v;
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import org.apache.commons.logging.Log; Hd2Sou4-j
import org.apache.commons.logging.LogFactory; o LuGW5wzj
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/** C1r]kF
* @author Joa [M
Z'i/
* #*}4=
*/ 224I%x.,
publicclass PageUtil { Le|Ho^h,Y
H.|FEV@
privatestaticfinal Log logger = LogFactory.getLog 3MNo&0M9
f{^C+t{r
(PageUtil.class); sJw3o7@pg
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/** S=eY`,'#R
* Use the origin page to create a new page M:Xswwq
* @param page + [|2k(U
* @param totalRecords oPo<F5M]d%
* @return % ]r@vjeyd
*/ h&NcN-["
publicstatic Page createPage(Page page, int GT|=Apnwr%
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totalRecords){ FL/@e$AK
return createPage(page.getEveryPage(), B~jl1g|
v?-pAA)ht
page.getCurrentPage(), totalRecords); BqCBH!^x
} aOyAP-m,
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/** tm#T8iF
* the basic page utils not including exception $*9h\W-)`Q
k
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handler jxZR%D
* @param everyPage )0yY|E\
* @param currentPage 7t0\}e
* @param totalRecords ncu
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* @return page _F;(#D
*/ 1Xu\Tm\Ux
publicstatic Page createPage(int everyPage, int Hh$x8ADf
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currentPage, int totalRecords){ CsQ}eW8uEf
everyPage = getEveryPage(everyPage); _;G"{e.=
currentPage = getCurrentPage(currentPage); r2M._}bF
int beginIndex = getBeginIndex(everyPage, o'D{ql
b U-Cd
currentPage); Tm.(gK
int totalPage = getTotalPage(everyPage, WG1UvPK
*jCXH<?R
totalRecords); ])7t!<
boolean hasNextPage = hasNextPage(currentPage, Hhx<k{B@7
D ( <_1
totalPage); *h-_
boolean hasPrePage = hasPrePage(currentPage); rPv+eM">
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returnnew Page(hasPrePage, hasNextPage, y9=/kFPRm
everyPage, totalPage, f)({;,q
currentPage, i(a2FKLy
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beginIndex); l$}h1&V7
} \XCs(lNh
2(\~z@g
privatestaticint getEveryPage(int everyPage){ s4@AK48
return everyPage == 0 ? 10 : everyPage; xzyV|(
} "e&S*8QhM
$83TA><a
privatestaticint getCurrentPage(int currentPage){ w5bD
return currentPage == 0 ? 1 : currentPage; Vv
B%,_\
} ([qw#!;w;
JY"<b6C^
privatestaticint getBeginIndex(int everyPage, int >/. -N
jI_TN5
currentPage){ 9mEC|(m*WK
return(currentPage - 1) * everyPage; `jSxq66L p
} pfe9n[
eRWTuIV6
privatestaticint getTotalPage(int everyPage, int R Q X
u `1cXL['
totalRecords){ 5%rD7/7N
int totalPage = 0; 'ZgrN14
Sy6Y3 ~7
if(totalRecords % everyPage == 0) %4Y/-xF}9,
totalPage = totalRecords / everyPage; ;_@u@$=~
else jQFAlO(E':
totalPage = totalRecords / everyPage + 1 ; HpiP"Sl
O3bo3Cm$
return totalPage; ;sE;l7
} *r6+Vz
8`EzvEm
privatestaticboolean hasPrePage(int currentPage){ c`yLn%Of%
return currentPage == 1 ? false : true; ZZL.&Ho
} -fI-d1@
Z!0D97^
privatestaticboolean hasNextPage(int currentPage, N?eWf +C
c:.k2u
int totalPage){ g)u
~GA*=
return currentPage == totalPage || totalPage == qgbp-A!2zF
{9q~bt
0 ? false : true; K9\`Wu_qL
} (]n^_G#-$
tY-{uHW&h
]R~K-cN`
} +Em+W#i%?
|QHDg(
d[;S n:B
9YS &RBJu
Nih8(pbe
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。 &k*sxW'
d#9
\]Ul&
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 ~Wp>tnl
u=I \0H
做法如下: |j($2.
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 u )cc
<)ozbv Xk
的信息,和一个结果集List: PzbLbH8A
java代码: f'` QW@U
qN%i$mJTo
N=]2vyh
/*Created on 2005-6-13*/ I]t ",s/j
package com.adt.bo; ys`"-o[*
Bj5_=oo+d
import java.util.List; ,)^4H>~V
@2ZE8O#I
import org.flyware.util.page.Page; `./$hh
c@!%.# |y
/** 7~n<%q/6
* @author Joa OPHf9T3H
*/ >|Ps23J#
publicclass Result { mxUM&`[
,$BbJQ5
private Page page; }{/3yXk[G
^GMM%
private List content; s|L}wtc
i7]\}w|
/** M|IR7OtLV
* The default constructor ?Ho~6q8O@
*/ l>p S23
public Result(){
&!7{2E\7C
super(); kH:! 7L_=
} :=9?XzCC
S- @E
/** do0;"O0
(
* The constructor using fields O%feB e
* v53qpqc
* @param page 92zo+bc
* @param content $]O;D~
*/ IjJO;
public Result(Page page, List content){ !##OQ
this.page = page; +*/XfPlr|
this.content = content; Y)="of
} &)Y26*(`
rZ}y'A
/** -UD^O*U
* @return Returns the content. (<y~]ig y
*/ \Nd8,hE
publicList getContent(){ ~:8}Bz2!5
return content; L O)&|9xw
} Npu#.)G
6%N.'wf
/** 9cV;W \ Tw
* @return Returns the page. k4WUfL d
*/ ,D#ssxV
public Page getPage(){ zW[fHa$m
return page; FwD"Pc2
} rmVF88/;
#|\w\MJamP
/** !8'mIXZ$
* @param content )<Cf,R
* The content to set. 4@|"1D3
*/ 0A$x'pU)
public void setContent(List content){ {{'GR"D
this.content = content; NFDh!HUm
} ZcT%H*Ib]9
BT[jD}?
/** ~CTe5PX c
* @param page fyb:eO}
* The page to set. 7-p9IFcA
*/ 3RSiu}
publicvoid setPage(Page page){ d"h*yH@
this.page = page; ^Bkwbj
} POZ5W)F(
} s+9q`k^
L?[NXLn+
(~}P.?C8
Atdr|2
I.V?O}
2. 编写业务逻辑接口,并实现它(UserManager, &35 6
RXo!K iQO
UserManagerImpl) heLWVI[so
java代码: >j&+mii
kX0hRX
H83Gx;
/*Created on 2005-7-15*/ PAYbsn
package com.adt.service; gG^A6Ol%D
HLD8W8
import net.sf.hibernate.HibernateException; dCbRlW
M|HW$8V3_2
import org.flyware.util.page.Page; :K-05$K
U^AywE]
import com.adt.bo.Result; Wc6Jgpl
2h_XfY'3pX
/** Q~p)@[q
* @author Joa Ib8*rL0p<L
*/ olHT* mr
publicinterface UserManager { 8XS_I{}?
)qyJwN
.D
public Result listUser(Page page)throws X`,=tM
>M2~BDZ
HibernateException; >
T$M0&<
F_<n8U:Y
} ]$4DhB
&oU) ,H
$oPx2sb
]npsclvJ
g?TPRr~$9
java代码: c >8IM
][gr(-6 8
:NHP,"
/*Created on 2005-7-15*/ 6}(;~/L
package com.adt.service.impl; C[4{\3\Va
Lo<-;;vQ
import java.util.List; -l:4I6-hi
[Dzd39aKr
import net.sf.hibernate.HibernateException;
+n'-%?LD&
H}ie D"T_
import org.flyware.util.page.Page; ApT8;F B
import org.flyware.util.page.PageUtil; CXAW>VdK_
aa-{,X"MF
import com.adt.bo.Result; 5{PT
import com.adt.dao.UserDAO; y Tb OBl
import com.adt.exception.ObjectNotFoundException; tz6N,4J?
import com.adt.service.UserManager; B_kjy=]O.
006qj.
/** zUQn*Cio e
* @author Joa ,
z-#B]
*/ ZyJ-}[z
publicclass UserManagerImpl implements UserManager { O
,9,=2j
dE_d.[!
private UserDAO userDAO; ;2&ym)`
pHftz-RS!
/** 0gIJ&h6*f
* @param userDAO The userDAO to set. u&E$(
*/ [ Q@rW5,-
publicvoid setUserDAO(UserDAO userDAO){ ;ndwVZ~,
this.userDAO = userDAO; \>G :mMk/
} \nzaF4+$
K/;*.u`:
/* (non-Javadoc) !GAU?J;<#2
* @see com.adt.service.UserManager#listUser %v"qFYVX"
=O.%)|
(org.flyware.util.page.Page) VoGyjGt&
*/ b}-/~l-:
public Result listUser(Page page)throws &{R]v/{p]
N!Q~?/!d
HibernateException, ObjectNotFoundException { QnZ7e#@UP
int totalRecords = userDAO.getUserCount(); e,X{.NS
if(totalRecords == 0) |eu:qn8
throw new ObjectNotFoundException =qNZ7>Qw
e.>>al
("userNotExist"); j@guB:0
page = PageUtil.createPage(page, totalRecords); X }""=
S<
List users = userDAO.getUserByPage(page);
%&81xAt
returnnew Result(page, users); RAs5<US:
} ;,2;J3,pA
C]f`
} -]-?>gkN5
3;F+.{Icc
vK7J;U+cJ
P-LdzVt(^
Be4n\c.
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 OBp&64
}~bx==SF6!
询,接下来编写UserDAO的代码: 8j^3_lD
3. UserDAO 和 UserDAOImpl: 9C"d7--
java代码: 9bb5?b/
Gc0/*8u/
Y )](jU%o
/*Created on 2005-7-15*/ Z&MfE0F/B
package com.adt.dao; MVYf-'\^
T/YvCbo
import java.util.List; AZ'"Ua
g-O}e4
import org.flyware.util.page.Page; ,enU`}9V*
F8En)#
import net.sf.hibernate.HibernateException; S>N/K
eI:;l];G9
/** ?]Wg{\NC6
* @author Joa T!3_Q/~^r
*/ x/]]~@:
publicinterface UserDAO extends BaseDAO { w.9'TR
WVkJ=r0Ny
publicList getUserByName(String name)throws 0%OV3`
t9Y?0O}/
HibernateException; =zXA0%
w}:&+B:
publicint getUserCount()throws HibernateException; r_EuLFM A
m@#@7[6]o
publicList getUserByPage(Page page)throws +1(L5Do}
S1Ql%Yk-(
HibernateException; zZ})$Ny(
"U6:z M
} etD8S KD
NUjo5.7
??g `c=R!V
u''~nSR3&
Smjg[
java代码: +:D90p$e
DAHQ7#qfQC
Q?7:XbN
/*Created on 2005-7-15*/ $%5f
package com.adt.dao.impl; 8Ug`2xS<_
#nS[]UbwZ
import java.util.List; }+3IM1VTW{
W%.ou\GN^t
import org.flyware.util.page.Page; Rd|xw%R\mb
dXvp-oi
import net.sf.hibernate.HibernateException; cJQ& #u
import net.sf.hibernate.Query; v<SCh)[-p
I,0Z* rw
import com.adt.dao.UserDAO; /`"&n1
QZ:xG:qyk;
/** B6hd*f
* @author Joa $hGiI
*/ @cT= t0*
public class UserDAOImpl extends BaseDAOHibernateImpl )VoQ/ch<
!/|^
)d^U
implements UserDAO { hD I}V1)
Bx&F* a;5
/* (non-Javadoc) ~3F\7%Iqc
* @see com.adt.dao.UserDAO#getUserByName 5lp};
;s(uaC3
(java.lang.String) LG6k
KG
*/ K,o@~fj
publicList getUserByName(String name)throws 7HkQ|~zGT
H*&ZXAKv
HibernateException { FA#?+kd
String querySentence = "FROM user in class SFdSA4D"
X8Ld\vZYn
com.adt.po.User WHERE user.name=:name"; 'dFhZ08u}
Query query = getSession().createQuery vs|_l!n3
oF9c>^s
(querySentence); LtDQgel"
query.setParameter("name", name); AT6:&5_`
return query.list(); Gd08RW
} 1FO T
zLa3Q\T
/* (non-Javadoc) Ad@Odx=o*R
* @see com.adt.dao.UserDAO#getUserCount() z%pD3J?>
*/ Es~|:$(N]|
publicint getUserCount()throws HibernateException { \h&ui]V
int count = 0; ZO !
String querySentence = "SELECT count(*) FROM M zbs#v0
J/o$\8tiMw
user in class com.adt.po.User"; xO<$xx
Query query = getSession().createQuery V;V,G+0Re
=:;KYuTr
(querySentence);
mGK-&|gq
count = ((Integer)query.iterate().next az=(6PX
1p[Z`m*9
()).intValue(); 3nJd0E
return count; i47xF7y\
} -#nfO*H}
eyiGe1^C
/* (non-Javadoc) sMikTwR/^
* @see com.adt.dao.UserDAO#getUserByPage R1%2]?
RRBokj)]
(org.flyware.util.page.Page) )E2^G)J$W
*/ |4F3Gu
publicList getUserByPage(Page page)throws g+-=/Ge
-a}d
@&
HibernateException { {0#p, l
String querySentence = "FROM user in class D =Pv:)*]
F9|\(St &
com.adt.po.User"; _IK@K6V1
Query query = getSession().createQuery 1M4I7*r
+foyPj!%
(querySentence); | Ts0h?"a
query.setFirstResult(page.getBeginIndex()) RQ1`k,R=
.setMaxResults(page.getEveryPage()); G\?q{
return query.list(); '<v/Gl\
} XU}|Ud562
cN{-&\
6L
} \(C_t1
:!wdqn
F_Q?0 Do0'
.i7bI2^
|Q'l&Gt6
至此,一个完整的分页程序完成。前台的只需要调用 "o*zZ;>^
-F+dRzxH
userManager.listUser(page)即可得到一个Page对象和结果集对象 qGE?[\t[6
r`Qzn" H
的综合体,而传入的参数page对象则可以由前台传入,如果用 mv1_vF:
GYD`
webwork,甚至可以直接在配置文件中指定。 l"\W] 'T:r
rSYzrVc
下面给出一个webwork调用示例: %#.HFK
java代码: NC*h7
SOyE$GoOsx
?w}E/(r
/*Created on 2005-6-17*/ :>Gm&w
(n
package com.adt.action.user; ugM,wT&~Y
By
t{3$
import java.util.List; 7kBULeBn|
ys5b34JN
import org.apache.commons.logging.Log; Q1G?e,Q
import org.apache.commons.logging.LogFactory; oJF@O:A
import org.flyware.util.page.Page; ^oFg5
%5=XszS
import com.adt.bo.Result; U20G{%%
import com.adt.service.UserService; |(e`V
import com.opensymphony.xwork.Action; 3
;F=EMz{
glk_*x
/** =H_|007C
* @author Joa Fejs9'cB
*/ ,6Kx1 c
publicclass ListUser implementsAction{ N/A.1W
=o5ZcC
privatestaticfinal Log logger = LogFactory.getLog M]?#]3XBNo
x}G["ZU}v]
(ListUser.class); =OIxG}*
4c2*)x$@
private UserService userService; a.a5qwG
yfS`g-j{~
private Page page; G)b6Rit
Vwp fkD`
privateList users; nn@"68]g
xf8C$|,
/* L$7
NT}L
* (non-Javadoc) %+iJpRK)7
* C,R_`%b%
* @see com.opensymphony.xwork.Action#execute() !GcH )
*/ e,qc7BJzK
publicString execute()throwsException{ KaC+x-%K
Result result = userService.listUser(page); H4 }^6><V
page = result.getPage(); />(e.)f
users = result.getContent(); x68$?CD
return SUCCESS; Pew-6u"
} NAjK0]SRY
g]9!Pi8jn
/** <qs>c<Vj
* @return Returns the page. mh>)N"
*/ <">tB"="b
public Page getPage(){ \$ L2xd
return page; KTd,^h
} \D] N*
+Sk ;
/** D^To:N7U
* @return Returns the users. dI<s)!
*/ !L"3Ot d
publicList getUsers(){ RQ#gn
return users; s{#ZRmc2B
} !']=7It{
+Gi~VW.
/** }wrZP}zM>
* @param page Z[
}0K3,5
* The page to set. KFBo1^9N
*/ y\b.0-z
publicvoid setPage(Page page){ E_]L8UC;m
this.page = page; >(Jy=m?
} TOV531
gT*0WgB
/** u1O?`
* @param users Ub%+8M
* The users to set. #Yi,EwD
*/ >I AwNr
publicvoid setUsers(List users){ DoAK]zyJA
this.users = users; =1fO"|L
} &yv%"BPV
nC^?6il
/** ?as)vYP
* @param userService ET1/oG<@
* The userService to set. *xXa4HB
*/ O`U&0lKi'
publicvoid setUserService(UserService userService){ {.OBcx
this.userService = userService; |&WeXVH E
} ZurQr}
} (Y\aV+9[
)e|Cd} 2
&=5
gUzCDB^.:
g
nJe!E
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, Urur/_]-%
1$ez}k,
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 :ak D
Xjc{={@p3
么只需要: \](IBI:
java代码: B5pMcw
?I&ha-."
12v5*G[X
<?xml version="1.0"?> u}hQF$a"
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ^%wj6
nw[DI%Tp
1.0//EN" "http://www.opensymphony.com/xwork/xwork- J
Sz'oA5
ja*k\w{U'
1.0.dtd"> VQV7W
_XIls*6AK
<xwork> w~@.&
WJCEiH
<package name="user" extends="webwork- ]8KAat~J
+c#:;&Gs
interceptors"> rMAH YH9
aG;6^$H~
<!-- The default interceptor stack name Z<6xQTx
iD,iv
--> XH&Fn+
<default-interceptor-ref =A&x
d"
I`w1IIY?m
name="myDefaultWebStack"/> 68?oV)fE
FDM&rQ
<action name="listUser" BFmYbK
+hL+3`TD#H
class="com.adt.action.user.ListUser"> C-4NiXa
<param %:oyHlz%
x;"!
name="page.everyPage">10</param> -]"=b\Q
<result *f|9A/*B3
=0 W`tx
name="success">/user/user_list.jsp</result> o.U$\9MNP
</action> O~F/{:U
^~}|X%q3
</package> T0n=nC}<
Gs%IZo_
</xwork> z5IHcZ
!PUbaF-.6
9'F-D
Q#P=t83
JmdXh/X
0HK03&
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 $,"{g<*k;
Ai\"w 0
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 vr56
f1
^ a%U *>P
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ,\Gn
a6=mE?JTB
JPL8fX-w
h+F@apUS
[o8a(oC
我写的一个用于分页的类,用了泛型了,hoho -}|GkTM
n's3!HQY[
java代码: rm2"pfs
Jhu<^pjs
j-|YE?AA
package com.intokr.util; M iIH&z
]4SnOSV?S
import java.util.List; `84pql,
)3v0ex@Jl
/** ;AKtbS;H
* 用于分页的类<br> +aRjJ/*
* 可以用于传递查询的结果也可以用于传送查询的参数<br> j{N;2#.u
* TN3, \qgV
* @version 0.01 I!lzOg4~
* @author cheng ;SkC[;`J
*/ FV^CSaN[R
public class Paginator<E> { *)"U5A/v)
privateint count = 0; // 总记录数 +(3"XYh
privateint p = 1; // 页编号 dj4 g
privateint num = 20; // 每页的记录数 %~P]x7%|
privateList<E> results = null; // 结果 ;>[).fX>/
84tuN
/** [^ck;4q
* 结果总数 d}tn/Eu?B
*/ ^T"9ZBkb
publicint getCount(){ K
!8+~[
return count; yAtM|:qq
} :xZ/c\
R[
S*ON
publicvoid setCount(int count){ ~!~VC)a*
this.count = count; ^ cN-
} #G{}Rd|!
#{7=
/** JGt4B
* 本结果所在的页码,从1开始 hZI9*=`,"
* N%6jZmKip
* @return Returns the pageNo. h*)spwF-
*/ LfyycC2E
publicint getP(){ #O]F5JB
return p; F0:Fv;
} ]7zDdI|
* b>W
/** T
:CsYj1
* if(p<=0) p=1 /MTS>[E
* i:OD)l
* @param p
hbR;zV|US
*/ e.G&hJr
publicvoid setP(int p){ xuO5|{h
if(p <= 0) R+lKQAyC0=
p = 1; l#%Y]1*
this.p = p; Jjik~[<q:
} <VB
eB/3MUz1
/** fMwJwMT8
* 每页记录数量 `j[)iok
*/ dGQxGt1
publicint getNum(){ -,q&Zm
return num; v[CX-CBZ?
}
V!c{%zd
]jG%<j9A
/** HoymGU`w
* if(num<1) num=1 g6Qzkvw)
*/ T{]Tb=
publicvoid setNum(int num){ `>rdn*B
if(num < 1) !OPK?7
num = 1; v;el= D
this.num = num; k<"ZNQm$.
} @`k!7?
Sq
2{"Wa|o`
/** ,V)yOLApVj
* 获得总页数 nfy"M),et
*/ y_qFXd
publicint getPageNum(){ :CSys62
return(count - 1) / num + 1; eN>=x40
} P_hwa1~d
j !&g:{ e
/** 9g"a`a?c
* 获得本页的开始编号,为 (p-1)*num+1 p}R)qz-=5U
*/ Il'+^u_ <
publicint getStart(){ $"J+3mO
return(p - 1) * num + 1; y M , hF
} 93)&
)eY3[>`
/** n1DD+@
* @return Returns the results. T*J]e|aF
*/ nXb;&n%
publicList<E> getResults(){ Wh(V?!^@5
return results; O9p8x2
} `P)atQ
N#C,_ k
public void setResults(List<E> results){ n8A*Y3~R
this.results = results; "1&C\}.7
} ?t'O\n)M
h?bm1e5kE
public String toString(){ ~(-B%Az
StringBuilder buff = new StringBuilder [#)-F_S
!(w\%$|
(); MJ8z"SKnV
buff.append("{"); KxGK`'E'r
buff.append("count:").append(count); IBQmm(+v
buff.append(",p:").append(p); t 4{{5U'\
buff.append(",nump:").append(num); @/`b:sv&*
buff.append(",results:").append opjrU$<]N
#J, `a.
(results); C \H%4p1r
buff.append("}"); jToA"udW/
return buff.toString(); F,P,dc
} )e4nKh],
+<"sC+2
} %S]5wR6;_
(VWTYG7
Av_1cvR: