Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 %@)R
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4_ypFuS ^
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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 Wp+lI1t
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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 O2?yI8|Jn
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分页支持类: [PB73q8
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java代码: GyMN;|
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package com.javaeye.common.util; F(zCvT
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import java.util.List; :*BN>*1^\r
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publicclass PaginationSupport { _'17C/
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publicfinalstaticint PAGESIZE = 30; xf/K+
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privateint pageSize = PAGESIZE; 2wnk~URj
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privateList items; pdER#7Tq
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privateint totalCount; i7PS=]TK\
3 !8#wn
privateint[] indexes = newint[0]; (9ZW^flY
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privateint startIndex = 0; )Ute
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public PaginationSupport(List items, int (T$cw(!
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totalCount){ 5'+g[eNyBV
setPageSize(PAGESIZE); g!'
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setTotalCount(totalCount); y9]7LETv\M
setItems(items); 8{!|` b'f
setStartIndex(0); H^5,];
} ULu@"
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public PaginationSupport(List items, int 5Za<]qxr
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totalCount, int startIndex){ rir,|y,
setPageSize(PAGESIZE); $xdo=4;|
setTotalCount(totalCount); d*e8P ep
setItems(items); qdwo 2u
setStartIndex(startIndex); EtPB_!
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} /Dd x[P5p=
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public PaginationSupport(List items, int 37:tu7e~c
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totalCount, int pageSize, int startIndex){ v;G/8>GRy
setPageSize(pageSize); l3u+fE,;_
setTotalCount(totalCount); s.rQiD
setItems(items); xzA!,75@U
setStartIndex(startIndex); #o[n.
} xu"-Uj1
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publicList getItems(){ r}e(MT:R'
return items; Q?LzL(OioN
} K3h];F!^
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publicvoid setItems(List items){ "Dk@-Ac
this.items = items; ^Ss<<
} PPrvVGP
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publicint getPageSize(){ T"3LO[j+
return pageSize; bv(+$YR
} 0%,W5w
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publicvoid setPageSize(int pageSize){ ib
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this.pageSize = pageSize; 2-qWR<E
} 42hG}Gt
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publicint getTotalCount(){ c)N_"#&
return totalCount; ZVJ6 {DS/
} !BrZTo
9}2/ko
publicvoid setTotalCount(int totalCount){ 3AR'Zvn
if(totalCount > 0){ Gw-{`<CxE
this.totalCount = totalCount; )BI%cD
int count = totalCount / tC$+;_=+F
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pageSize; ? eI)m
if(totalCount % pageSize > 0) n} !')r
count++; /Us+>vg!
indexes = newint[count]; dc~vQDNw[X
for(int i = 0; i < count; i++){ K%BFR,)g
indexes = pageSize * J0e^v
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i; -{JReplc
} psx_gv,
}else{ _C1u}1hW#
this.totalCount = 0; ]Hi1^Y<
} Q2]7|C
} "30=!k
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publicint[] getIndexes(){ !@Vj&>mH$
return indexes; w^HI
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} bOrE86v:
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publicvoid setIndexes(int[] indexes){ rO#$SW$YW
this.indexes = indexes; JUDZ_cGr
} y,Bj,zw
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publicint getStartIndex(){
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return startIndex; ,g?M[(wtc
} 0e]J2>
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publicvoid setStartIndex(int startIndex){ {[NQD3=+F
if(totalCount <= 0) 1y U!rEH
this.startIndex = 0; OEbZs-:
elseif(startIndex >= totalCount) c<cYX;O
this.startIndex = indexes X3gYe-2
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[indexes.length - 1]; _uJ6Vy
elseif(startIndex < 0) R*LPwJuv
this.startIndex = 0; Ebi~gGo
else{ o!y<:CGL
this.startIndex = indexes AlrUfSBB
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[startIndex / pageSize]; >[T6/#M
} M_75bU
} Ud>hDOJ3
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publicint getNextIndex(){ PiR`4Tu
int nextIndex = getStartIndex() + tC f@v'1t
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pageSize; rSW{1o'
if(nextIndex >= totalCount) C;70,!3
return getStartIndex(); V)`Q0}
else G~*R6x2g
return nextIndex; YWi Y[
} CSm(yB{|pC
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publicint getPreviousIndex(){ 5HvYy
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int previousIndex = getStartIndex() - Xe/7rhov
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pageSize; lu1T+@t
if(previousIndex < 0) d]=>U^K
return0; hiR+cPSF
else l>HB 0o
return previousIndex; =5%}CbUU)4
} ={ 190=\9
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} ]Qx-f*
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抽象业务类 e<Oz%
java代码: V-i:t,*lk(
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/** )MM(HS
* Created on 2005-7-12 )@.ODW;`
*/ @
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package com.javaeye.common.business; AucX4J<
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import java.io.Serializable; 1BzU-Ma
import java.util.List; WPu%{/[
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import org.hibernate.Criteria; 5M3)7
import org.hibernate.HibernateException; i2Gh!5]f
import org.hibernate.Session; H{d/%}7[v
import org.hibernate.criterion.DetachedCriteria; U.WMu%
import org.hibernate.criterion.Projections; k}{K7,DM
import n^epC>a" b
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org.springframework.orm.hibernate3.HibernateCallback; KiNluGNt
import L= <,+m[!
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org.springframework.orm.hibernate3.support.HibernateDaoS W?12'EG}xa
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upport; m%OX<
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import com.javaeye.common.util.PaginationSupport; 1g|6,J
MP 8s}
public abstract class AbstractManager extends GlXzH1wZ
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HibernateDaoSupport { yucbEDO.
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privateboolean cacheQueries = false; BQ~&gy{
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privateString queryCacheRegion; =(5}0}j
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publicvoid setCacheQueries(boolean zhwajc
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cacheQueries){ lGX_5R
this.cacheQueries = cacheQueries; v[?eL0Z
} *_yp]z"
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publicvoid setQueryCacheRegion(String S#7.y~e\
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queryCacheRegion){ X_I.f6v{
this.queryCacheRegion = #+P)X_i`
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queryCacheRegion; s|8_R;
} x "PMi[4
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publicvoid save(finalObject entity){ ((_v>{
getHibernateTemplate().save(entity); 4T#Z[B[
} TWQ{,
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publicvoid persist(finalObject entity){ *W<g%j-a
getHibernateTemplate().save(entity); tZY(r
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} wsfn>w?!V
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publicvoid update(finalObject entity){ ^S`c-N
getHibernateTemplate().update(entity); qUp DmH
} =
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publicvoid delete(finalObject entity){ j6)@kW9x
getHibernateTemplate().delete(entity); T k>N4yq
} $yg}HS7HC
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publicObject load(finalClass entity, dCMWv~>
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finalSerializable id){ kv3jbSKCT
return getHibernateTemplate().load axi%5:I
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(entity, id); re}P
} -{fbZk&A
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publicObject get(finalClass entity, Nb;Yti@Y.
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finalSerializable id){ ;zvg] %
return getHibernateTemplate().get =Wk!mGc
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(entity, id); A@"CrVE
} Lpdp'9>I
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publicList findAll(finalClass entity){ }mw31=2bD
return getHibernateTemplate().find("from 3AD^B\<gB
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" + entity.getName()); e[8p /hId
} "^ cn9AG{
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publicList findByNamedQuery(finalString %@jv\J
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namedQuery){ ~8EG0F;t
return getHibernateTemplate C'}8
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().findByNamedQuery(namedQuery); m/0t;
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} `795K8
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publicList findByNamedQuery(finalString query, P
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finalObject parameter){ -pR1xsG
return getHibernateTemplate RyxIJJui
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().findByNamedQuery(query, parameter); U;4:F{3m
} rT
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publicList findByNamedQuery(finalString query, @[S\ FjI
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finalObject[] parameters){ IXf@YV
return getHibernateTemplate KyAQzN 9
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().findByNamedQuery(query, parameters); Aj4i}pT
} &`63"^y
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publicList find(finalString query){ A:ef}OCL
return getHibernateTemplate().find P Z;O
pp
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(query); 7Q.?]k&
} Y0U<l1(|
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publicList find(finalString query, finalObject }45&s9m=
([ xYOxcp5
parameter){ W%.Kr-[?`o
return getHibernateTemplate().find 'on, YEp
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(query, parameter); OY6lt.t
} *Oo2rk nQ
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public PaginationSupport findPageByCriteria b07 MTDFH7
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(final DetachedCriteria detachedCriteria){ qGgT<Rd~1
return findPageByCriteria Zcv1%hI
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); o% !a
} c0jC84*v
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public PaginationSupport findPageByCriteria z/N~HSh!d
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(final DetachedCriteria detachedCriteria, finalint /'p(X~X:l
'LR5s[$j
startIndex){ }dE0WJcO
return findPageByCriteria m^Btr
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(detachedCriteria, PaginationSupport.PAGESIZE, ?
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startIndex); -mG3#88*
} $q{-)=-BXQ
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public PaginationSupport findPageByCriteria qI"@ PI!s
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(final DetachedCriteria detachedCriteria, finalint Ah28D!Gor
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[
pageSize, Bi)1*
finalint startIndex){ Fmk,
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return(PaginationSupport) }ruBbeQ
Z@ *^4Ve
getHibernateTemplate().execute(new HibernateCallback(){ B9n$8QS
publicObject doInHibernate N'!a{rF
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(Session session)throws HibernateException { =\?KC)F*e
Criteria criteria = ~k4S~!(U0
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detachedCriteria.getExecutableCriteria(session); SV}I+O_w
int totalCount = zN {'@B
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((Integer) criteria.setProjection(Projections.rowCount < ppg$;
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()).uniqueResult()).intValue(); +EJIYvkFm
criteria.setProjection O!kBp(?]
f 6Bx>lh
(null); ; 7[5%xM
List items = +hRAU@RA
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criteria.setFirstResult(startIndex).setMaxResults TP[<u-@G
kA{[k
(pageSize).list(); Uo<d]4p $
PaginationSupport ps = [F/>pL5U$
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new PaginationSupport(items, totalCount, pageSize, KZ
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startIndex); E=3<F_3W
return ps; YUat}-S
} ne4hR]:
}, true); G@ XKE17
} _K3?0<=4
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public List findAllByCriteria(final 5vxJ|Hse@
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DetachedCriteria detachedCriteria){ YgCJ s;
return(List) getHibernateTemplate 0$%:zHi5g
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().execute(new HibernateCallback(){ %vDN{%h8
publicObject doInHibernate aRdzXq#x
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(Session session)throws HibernateException { Tf)qd\
Criteria criteria = K 38e,O
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detachedCriteria.getExecutableCriteria(session); u1xCn\
return criteria.list(); 0~Z>}(
} Ro`9Ibqr
}, true); YN#i^(
} De@GNN"-
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public int getCountByCriteria(final >fJY
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DetachedCriteria detachedCriteria){ Fx*iAH\e
Integer count = (Integer) d:.S]OI0
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getHibernateTemplate().execute(new HibernateCallback(){ D.9qxM"Z>
publicObject doInHibernate W~z
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(Session session)throws HibernateException { 4R0'$Ld4
Criteria criteria = F$y3oX
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detachedCriteria.getExecutableCriteria(session); h5e(Avk
return 4!64S5(7t
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criteria.setProjection(Projections.rowCount (B{`In8G>y
s4/4o_[W
()).uniqueResult(); A}v!vVg
} L\)ssOuh
}, true); )-%3;e<w
return count.intValue(); @9lV~,,U
} 9AO`Zk{/Ez
} Gjfb<
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用户在web层构造查询条件detachedCriteria,和可选的 >M=_:52.+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 E1 IT>_
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PaginationSupport的实例ps。 4u- mE
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ps.getItems()得到已分页好的结果集 ,RjE?M%
ps.getIndexes()得到分页索引的数组 )voJq\Y)%
ps.getTotalCount()得到总结果数 !_C*2+f
ps.getStartIndex()当前分页索引 RC'4%++Nz
ps.getNextIndex()下一页索引 >W Tn4SW@
ps.getPreviousIndex()上一页索引 /j46`F
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 L/\s~*:M
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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 (iQ<
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一下代码重构了。 @+Ch2Lod
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我把原本我的做法也提供出来供大家讨论吧: }7?_>
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首先,为了实现分页查询,我封装了一个Page类: *-uA\
java代码: uH*moVw@5
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/*Created on 2005-4-14*/ .n$c+{
package org.flyware.util.page; U9"g;t+/
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/** #uTNf78X
* @author Joa _L?MYkD
* )Y4;@pEU
*/ W]Bc7JM]T+
publicclass Page { e1cqzhI=nA
HiAj3
/** imply if the page has previous page */ CjR!dh1w_
privateboolean hasPrePage; \f~m6j$D_
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/** imply if the page has next page */ nA owFdCD
privateboolean hasNextPage; 6g*?(Y][
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/** the number of every page */ 6%yt"XmT
privateint everyPage; E8X(AZ 2
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/** the total page number */ X~UrAG}_
privateint totalPage; 5&)T[Q X`
p^.qwP\P
/** the number of current page */ we:P_\6
privateint currentPage; L%S(z)xX3
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/** the begin index of the records by the current -S\gDB bb
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query */ ,9,cN-/a
privateint beginIndex; P^(uS'j)+
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/** The default constructor */ g'X{
public Page(){ 88 x2Hf5I
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} GJs{t1
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/** construct the page by everyPage z}BuR*WSY{
* @param everyPage K<wg-JgA
* */ &/m0N\n?
public Page(int everyPage){ t,NE`LC
this.everyPage = everyPage; tJe5`L
} #~}4< 18
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/** The whole constructor */ +MR]h
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public Page(boolean hasPrePage, boolean hasNextPage, xig4H7V
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int everyPage, int totalPage, o[I
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int currentPage, int beginIndex){ i/{dD"HwM
this.hasPrePage = hasPrePage; h 8<s(WR
this.hasNextPage = hasNextPage; P*|qbY
this.everyPage = everyPage; y3XR:d1cg
this.totalPage = totalPage; }|UTwjquBD
this.currentPage = currentPage; u+lNcyp"MW
this.beginIndex = beginIndex; @[LM8 @:
} nt:ZO,C:R
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/** HXm&`
* @return \h>6k
* Returns the beginIndex. 1y3)ogL
*/ n\GN}?4
publicint getBeginIndex(){ x)R1aq
return beginIndex; y(<+=
} '}l7=r
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/** q#6|/R*
* @param beginIndex t/lQSUip
* The beginIndex to set. -{2Vz[ [
*/ lb{X 6_.
publicvoid setBeginIndex(int beginIndex){ i);BTwW)#]
this.beginIndex = beginIndex; uS<og P
} #.<Dq8u
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/** lT?Vt`==~M
* @return :]JMsa6
* Returns the currentPage. )Vz=:.D
*/ vs^)=
publicint getCurrentPage(){ g#Z7ReMw
return currentPage; =qvn?I^/
} 4`Cgz#v
{
zr ~4@JTS
/** !eHQe7_
* @param currentPage 5d;(D i5z
* The currentPage to set. L)i6UAo
*/ 9=J 3T66U
publicvoid setCurrentPage(int currentPage){ nt%fJ k
this.currentPage = currentPage; /2Z7
} a|5<L
]`q]\EH
/** y*Gq VA[
* @return ^S`N\X
* Returns the everyPage. mg< v9#
*/ (M?VB*sm0
publicint getEveryPage(){ ov5g`uud
return everyPage; \#v(f2jPF
} *:%I|5
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/** ol1J1Zg
* @param everyPage QYj*|p^x
* The everyPage to set. Y
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*/ bzaweAH
publicvoid setEveryPage(int everyPage){ ;Kh[6{ W
this.everyPage = everyPage; 8%`h:fE
} %J+ w9Z
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/** 9!PM1<p
* @return "yK)9F[9Mo
* Returns the hasNextPage. 2eRv{_
*/ ?pdN!zOeL
publicboolean getHasNextPage(){ de9e7.(2
return hasNextPage; zjTCq; G
} peew<SX
x6Tpt^N}
/** 2uT@jfj:r
* @param hasNextPage Y=i_2R2e2
* The hasNextPage to set. S\ K[l/
*/ z%]3`_I
publicvoid setHasNextPage(boolean hasNextPage){ M96Nt&P`
this.hasNextPage = hasNextPage; g*-}9~
} L'$({
Zbr1e5?
/** jgqeDl\=+
* @return .kyes4Z
* Returns the hasPrePage. E<p<"UjcCJ
*/ sZwa#CQK q
publicboolean getHasPrePage(){ 9&HaEAme
return hasPrePage; E Uq6)
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} >CqZ75>
"^ aSONz
/** 5k
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* @param hasPrePage "AlR%:]24~
* The hasPrePage to set. _dc,}C
*/ S#0C^
publicvoid setHasPrePage(boolean hasPrePage){ cpH*!*S
this.hasPrePage = hasPrePage; pf#R]
} Abpzf\F
kaRjv
/** l}FA&c"
* @return Returns the totalPage. W6)XMl}n
* Bnz}:te}
*/ gF]IAZCi
publicint getTotalPage(){ ?IDkDv!na~
return totalPage; DG=_E\"#
} KfSbm?
qL$\[(
/** wuhL r(
* @param totalPage {)4@rM
* The totalPage to set. bv``PSb3
*/ A&d_!u>
publicvoid setTotalPage(int totalPage){ #%]?e
N
this.totalPage = totalPage; Pk8(2fAYk
} mp0s>R
=T$2Qo8
} J=H8^4M
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dCWq~[[
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 R_IT${O
wh3Wuh?x
个PageUtil,负责对Page对象进行构造: h m(
java代码: $wcV~'fM
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/*Created on 2005-4-14*/ 0
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package org.flyware.util.page; "9RW<+
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import org.apache.commons.logging.Log; '1lz`CAB+
import org.apache.commons.logging.LogFactory; /pp;3JPf
R;w1& Z
/** s="cg0PD
* @author Joa j[w5#]&%
* oTeQY[%$
*/ WhL"-f
publicclass PageUtil { jYh.$g<`0+
OQ<NB7'n0A
privatestaticfinal Log logger = LogFactory.getLog <$%Y#I'zX
VKr
oikz@]
(PageUtil.class); &RlYw#*1.
8yGo\\=T
/** aVn+@g<.
* Use the origin page to create a new page {z# W-
* @param page PR>%@-Vgj
* @param totalRecords mTa^At"
* @return V/8yW3]Xy
*/ <h~_7Dn
publicstatic Page createPage(Page page, int "'c
=(P
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totalRecords){ g1q%b%8T
return createPage(page.getEveryPage(), rgu7g
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page.getCurrentPage(), totalRecords); jAD{?/RB}
} HF%)ip+
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/** o &E2ds3
* the basic page utils not including exception t<qXXQ&5
CHM+@lD
handler GV
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* @param everyPage 3]/Y=A
* @param currentPage `{\10j*B
* @param totalRecords i'0ol^~y6
* @return page j"<F?k@`Q
*/ [u8JqX
publicstatic Page createPage(int everyPage, int YfH+kDT
LMYO>]dg
currentPage, int totalRecords){ _MGhG{p7t
everyPage = getEveryPage(everyPage); Il#9t?/
currentPage = getCurrentPage(currentPage); n4EZy<~m
int beginIndex = getBeginIndex(everyPage, h!1CsLd[
btB> -pT
currentPage); K9UWyM<(2C
int totalPage = getTotalPage(everyPage, :sekMNM
>c@1UEwkm
totalRecords); y7#vH<
boolean hasNextPage = hasNextPage(currentPage, y &%2
dRLvej,
totalPage); a~;`&Uj
boolean hasPrePage = hasPrePage(currentPage); xw rleB
r/6h}
returnnew Page(hasPrePage, hasNextPage, tJ9`Ys
everyPage, totalPage, O0>^?dsL
currentPage, _ 6'HBE
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beginIndex); CFx$r_!~
} 4K$d%
w24@KaKFo
privatestaticint getEveryPage(int everyPage){ xr4kBC
t
return everyPage == 0 ? 10 : everyPage; 31}kNc}n
} iLG~_Ob:
(yi{<$U*
privatestaticint getCurrentPage(int currentPage){ nYO4JlNP
return currentPage == 0 ? 1 : currentPage; 3+ r8yiY
} Uzd\#edxJ
MQGR-WV=5
privatestaticint getBeginIndex(int everyPage, int mkt%|Kb.
#k<j`0kiq
currentPage){ ,(CIcDJ2U_
return(currentPage - 1) * everyPage; 0~j0x#
} S%m$LM]NCg
EXYr_$gRs
privatestaticint getTotalPage(int everyPage, int W%cJ#R[o
g"L$}#iTsl
totalRecords){ fRd^@@,[
int totalPage = 0; Sf*b{6lcC
D.R 7#^.
if(totalRecords % everyPage == 0) E14Dq#L
totalPage = totalRecords / everyPage; ~uz 4
else 2:l8RH!Y
totalPage = totalRecords / everyPage + 1 ; ?)B\0` %*'
y2,M9
return totalPage; {QTnVS't 0
} 4&([<gyR<
!5K9L(gqb
privatestaticboolean hasPrePage(int currentPage){ -V)DKf"f
return currentPage == 1 ? false : true; -:o4|&g<*
} P ||:?3IH
2hI|]p
privatestaticboolean hasNextPage(int currentPage, *_7%n-k
V0x;*)\PYm
int totalPage){ lZ9rB^!
return currentPage == totalPage || totalPage == P>3
;M'KsO
/a!M6:,pX
0 ? false : true; i>68gfx
} .0>2j(
aM|^t:
s!j[Ovtx
} _]whHS+
6vQCghI
!nkjp[p
Wc+)EX~KS
$kef_*BQg
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 oMV<Yn_<
/G h?z
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 /
`Glf|
Th6xwMq
做法如下: t\$P*_
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %Z=%E!*
{FU,om9
的信息,和一个结果集List: k*3F7']8
java代码: 6eh\-+=
tmJ-2
^%?*u;uU%
/*Created on 2005-6-13*/ OF)G2>t
package com.adt.bo; '-7rHx
IE|$mUabm
import java.util.List; plRBfw>]N
Z4 +6'
import org.flyware.util.page.Page; sV))Z2sq
U\
Et
/** xQ=sZv^M
* @author Joa |99/?T-QW
*/ eZMDt B
publicclass Result { V6C*d:
=x/Ap1
private Page page; O:Ixy?b;Z
OJGEX}3'
private List content; `"/s," c:D
*+ql{\am4N
/** ?B"k9+%5ej
* The default constructor ""JTU6]MS
*/ R>iRnrn:-
public Result(){ tJ
NJS
super(); *?a rEYc8
} b!7*bFTt
69{BJ]q
/** x"9e eB,
* The constructor using fields oK5"RW
* ([r4N#lx
* @param page 8tR(i[L
* @param content T5g}z5~"
*/ x9s7:F
public Result(Page page, List content){ =skw@c^
this.page = page; 2|KgRk|!
this.content = content; V kA$T8
} [!ghI%VK
ok"v`76~f5
/** [zO:[i 7
* @return Returns the content. 9Q<8DMX^
*/ WPmH4L>T
publicList getContent(){ `m.).Hda
return content; =o@CCUKpj
} fZqqU|tq
rfgkw
/** l$PSID
* @return Returns the page. ^]&uMkPN
*/ )]/gu\90
public Page getPage(){ kPm{ tc
return page; ETw7/S${
} hGPo{>xR
mIK-a{?G
/** TzC'xWO
* @param content Ua>lf8w<
* The content to set. &Hb;; Ic(
*/ csceu+IA
public void setContent(List content){ ;#F/2UgHB
this.content = content; #mI{D\UR
} 5/vfmDt3'G
INi9`M.h
/** CWP),]#n
* @param page o=t@83Fh5
* The page to set. \>T+\?M
*/ `OL@@`'^{S
publicvoid setPage(Page page){ bjQp6!TsZ
this.page = page; u?(@hUV.
} TY(B]Q_o
} raWs6b4Q
^PnXnH?
r\OunGUP
iYqZBLf{S
kYlsjM
2. 编写业务逻辑接口,并实现它(UserManager, 0pO{ {F
T<hS
UserManagerImpl) s$cr|p;7#
java代码: 'MM%Sm,
81gcM?
O_zW/#
/*Created on 2005-7-15*/ LW={| 3}
package com.adt.service; P=.yXirm?
VH.mH<
import net.sf.hibernate.HibernateException; DChqcdx~~
{XHAQ9'
import org.flyware.util.page.Page;
PTU_<\
V`/E$a1&
import com.adt.bo.Result; UlG8c~p
=cwQG&as
/** E[:eMJR
* @author Joa +3a}~p W
*/ KASuSg+
publicinterface UserManager { |K|[>[?Z/
OcA_m.
public Result listUser(Page page)throws |WiE`&?xP
hA6
HibernateException; z%)~s/2Rs
kLsp0%2
} 1V\tKDM
)\S3Q
o!]muO*Rm
Jy#c 6
dRdI('
java代码: bW]7$?acv
HE;}B!>
iyA=d{S;V
/*Created on 2005-7-15*/ ~XzT~WxW
package com.adt.service.impl; L}~"R/iWCT
$?_/`S13
import java.util.List; rr@h9bak;g
@U8}K#
import net.sf.hibernate.HibernateException; M id v
jR1o<]?
import org.flyware.util.page.Page; J0ysZ]
import org.flyware.util.page.PageUtil; lOp7rW]$
Oe)d|6=
import com.adt.bo.Result; &kR*J<)V
import com.adt.dao.UserDAO; 8t1XZ
import com.adt.exception.ObjectNotFoundException; S55h}5Y
import com.adt.service.UserManager; \;!}z3W w
&z;bX-"E
/** TANv)&,|9
* @author Joa i;flK*HOZ9
*/ -w dbH`2Z"
publicclass UserManagerImpl implements UserManager { e^LjB/<Th
WE{fu{x
private UserDAO userDAO; XIGz_g;#'w
{Jna'
eS
/** ~+A(zlYr~
* @param userDAO The userDAO to set. -wh?9?W
*/ h SeXxSb:
publicvoid setUserDAO(UserDAO userDAO){ ]9
JLu8GO
this.userDAO = userDAO; R)@2={fd}
} :F |ll?
xU1_L*tu '
/* (non-Javadoc) |rgp(;iO
* @see com.adt.service.UserManager#listUser 3s]aXz:
=bBV
A0y
(org.flyware.util.page.Page) NihUCj"
*/ {\WRW}iO
public Result listUser(Page page)throws 2;wpD2
>1}@Q(n/}{
HibernateException, ObjectNotFoundException { `hl8j\HV<}
int totalRecords = userDAO.getUserCount(); kqH:H~sgD
if(totalRecords == 0) eh39"s
throw new ObjectNotFoundException 0.aIcc
]\C wa9
("userNotExist"); W? F Q
page = PageUtil.createPage(page, totalRecords); [u $X.=(
List users = userDAO.getUserByPage(page); dwpE(G y6c
returnnew Result(page, users); RoFOjCc>D.
} tEN8S]X
( GW"iL#.
} `<Q[$z
kl~)<,/@
y}F;~H~P
th1;Ym+Ze
z/I\hC9i
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,M.phRJ-`
lR>p
询,接下来编写UserDAO的代码: EKD?j
3. UserDAO 和 UserDAOImpl: Ob&m&2s,
java代码: KB"N',kG
9Q.@RO$%C
)n&6= Li
/*Created on 2005-7-15*/ M!/!*,~
package com.adt.dao; 2dyS_2u
mDXG~*1
import java.util.List; j S4\;
/V{1Zw=
import org.flyware.util.page.Page; |iA8aHFU
&7XsyDo6
import net.sf.hibernate.HibernateException; Ei7Oi!1
+8|9&v`
/** Ox5Es
* @author Joa |@1M'
*/ TE5J
@I
publicinterface UserDAO extends BaseDAO { tb^/jzC
j8G$ , ~v
publicList getUserByName(String name)throws l;SXR <EU
GBl[s,g[|
HibernateException; O'Q,;s`uC
b8 E{~z
publicint getUserCount()throws HibernateException; xHD$0eq
b['v0x
publicList getUserByPage(Page page)throws noso* K7
vdcPpj^d5
HibernateException; |vw],r6
=.qX u+
} -@tj0OHg
Sy/Z}H
Bp_8PjQ
rE Me=>^
OQIr"
java代码: Zq~Rkx
;Nw)zS
HUChg{[
/*Created on 2005-7-15*/ <L('RgA@X
package com.adt.dao.impl; ' GUCXx
:Xs4 C%H;
import java.util.List; 4wN5 x[vp
>m:n6M'r
import org.flyware.util.page.Page; ~>H,~</`
o-o -'0l
import net.sf.hibernate.HibernateException; ?t/G@
import net.sf.hibernate.Query; `TYC]9
1bFGoLAEFl
import com.adt.dao.UserDAO; ?iZM.$![
l;rA}?,.^
/** H_JE)a:+
* @author Joa gBO,
*/ ckb(+*+l
public class UserDAOImpl extends BaseDAOHibernateImpl &ty-aB=F
Lq62
implements UserDAO { qg/FI#r
Dkx}}E:<
/* (non-Javadoc) BCuoFw)
* @see com.adt.dao.UserDAO#getUserByName "L;@qCfhO
%^d<go^
(java.lang.String) =CW> ;h]
*/ MGf *+!y,
publicList getUserByName(String name)throws +w7U7"
xQ
|2=@8_am
HibernateException { |@~_&g
String querySentence = "FROM user in class O+|ipw*B%
V!(7=ku!`
com.adt.po.User WHERE user.name=:name"; 73B[|J*
Query query = getSession().createQuery }d>Xh8:%)
D@O5G d
(querySentence); _#1EbvO*l
query.setParameter("name", name); L/E7xLz
return query.list(); tDavp:M1v
} 3:G$Y:#P
,6X__Z#rGT
/* (non-Javadoc) NJSbS<O
* @see com.adt.dao.UserDAO#getUserCount() o:&8H>(hn]
*/ xkRS?Q g
publicint getUserCount()throws HibernateException {
iDx(qdla
int count = 0; pN)x,<M)
String querySentence = "SELECT count(*) FROM <CB%e!~.9
&Nh
zEl1
user in class com.adt.po.User"; k~Q
5Cs
Query query = getSession().createQuery '7}2}KD
q7rb3d
(querySentence); Td|u-9OM
count = ((Integer)query.iterate().next Cn{v\Q~.4
?0M$p
()).intValue(); }30Sb&"
return count; +0)M1!gK
} YR? E
z<p
|h%HUau
/* (non-Javadoc) eXD~L&s[
* @see com.adt.dao.UserDAO#getUserByPage 7W*a+^
XjCx`bX^<
(org.flyware.util.page.Page) 3~7!=s\v
*/ EJ>rW(s
publicList getUserByPage(Page page)throws @/?i|!6
b`$qKO
HibernateException { B'Jf&v
String querySentence = "FROM user in class 4:S]n19nq
&ds+9A
com.adt.po.User"; 0g6sGz=
Query query = getSession().createQuery OjAdY\
]1
n.qT7d(
(querySentence); IU5T5p
query.setFirstResult(page.getBeginIndex()) Yi,`uJKh
.setMaxResults(page.getEveryPage()); V9SL96'[I
return query.list(); S-}c_zbl;
} M 87CP=yc
?hGE[.(eh]
} JV@G9PT
MUsF
pW@W-k:u
-.y1]4
[|YvVA
至此,一个完整的分页程序完成。前台的只需要调用 SD :D8"8
b9#(I~}
userManager.listUser(page)即可得到一个Page对象和结果集对象 kW2DKr-[
RD"-(T
的综合体,而传入的参数page对象则可以由前台传入,如果用 i}zz!dJTE
Tg"? TZO~
webwork,甚至可以直接在配置文件中指定。 @MVul_@6
N&p0Emg
下面给出一个webwork调用示例: (&Jo.
<
java代码: (CRx'R
Bm,Vu 1]t
$OdBuJA
/*Created on 2005-6-17*/ 'tw
]jMD
package com.adt.action.user; wggB^ }~
x>B\2;
import java.util.List; ^\Z+Xq1~/
[T,^l#S1
import org.apache.commons.logging.Log; eUZk|be
import org.apache.commons.logging.LogFactory; #) :.1Z?
import org.flyware.util.page.Page; n[gE[kw
d{Jk:@.1
import com.adt.bo.Result; 1++g@8
import com.adt.service.UserService; vG'#5%,|
import com.opensymphony.xwork.Action; 8Th,C{
O1c:X7lHc
/** o+}k$i!6
* @author Joa I/O/*^T
*/ Z#Kf%x.
publicclass ListUser implementsAction{ yc~<h/}#
=k.%#h{
privatestaticfinal Log logger = LogFactory.getLog [|1I.AZ{
aQ$sn<-l
(ListUser.class); xSd&xwP
BCe'J!
private UserService userService; ^Z#G_%\Y:
wEM=Tr/h
private Page page; YPI,u7-
qe#5;#
privateList users; GJZjQH-#P
bY.VNA
/* #@OPi6.#!<
* (non-Javadoc) c'tQA
* #:0-t!<0C
* @see com.opensymphony.xwork.Action#execute() ; veD?|
*/ "r_wgl%
publicString execute()throwsException{ J_Tz\bZ3)
Result result = userService.listUser(page); ZHN'j ]?
page = result.getPage(); AK,'KO%{=
users = result.getContent(); ~?Ky{jah:^
return SUCCESS; cjPXrDl{\
} z,ERq,g+L
YmaS,Q-
/** PIa!NPy
* @return Returns the page. ;10YG6:
*/ m!Z<\2OP
public Page getPage(){ O 1z0dHa
return page; 4>0q0}J=5
} z/xPI)R[
;j/$%lC
/** .gDq+~r8O
* @return Returns the users. $Q8
&TM}E
*/ 5[SwF&zZ
publicList getUsers(){ SDil\x
return users; ebI2gEu;a
} >*h+N?
m
`8W HVC$
/** Rv9jLH
* @param page 9D1WUUa
* The page to set. E3O^Tg?j
*/ }|=/v(D
publicvoid setPage(Page page){ ]5S`y{j1
this.page = page; lJ-PW\P
} XP?jsBE
QcQ%A%VIV
/** |A'I!Jm
* @param users kJ FWk
* The users to set. /9G72AD!
*/ Lcpe*C x-
publicvoid setUsers(List users){ Ha-]U:Vcx
this.users = users; U[f00m5{HV
} ?$109wZ:9
N5=BjXSAg
/** 1Y'4 g3T
* @param userService d6QrB"J`
* The userService to set. <Pt?N2]A|
*/ Blzvn19'h
publicvoid setUserService(UserService userService){ I61S0lz/
this.userService = userService; vlbZ5
} !="q"X/*
} v5S9h[gT
(~^fx\-S
2uE<mjCt-r
6I@j$edZ
(4L/I
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, BM,hcTr?
UrvUt$WO
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 dz9U.:C
0wv#AT
么只需要: 1}DA| !~
java代码: 0Xh_.PF
Xh;.T=/E|
VjM3M<!g>M
<?xml version="1.0"?> hHE~/U
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork wL?Up>fr
v&YeQC>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- (CxA5u1|l
1^WGJ"1
1.0.dtd"> f*XCWr
@=VxWU
<xwork> M-"j8:en
f"5O'QHGQK
<package name="user" extends="webwork- mgjJNzclL
b]4dmc*N+
interceptors"> ux&"TkEp
W%g*sc*+
<!-- The default interceptor stack name I1E9E$m5\<
Wgls+<l8
--> ;AEfU^[
<default-interceptor-ref LBK{-(%
luf5-XT
name="myDefaultWebStack"/> g^]Iw~T6$
OT])t<TF6
<action name="listUser" +{I_%SsG
`uMEK>b
class="com.adt.action.user.ListUser"> k
<oB9J
<param |NfFe*q0;8
^Q s}2%
name="page.everyPage">10</param> }]vUr}Els
<result :DN!1~ZtW
<xy@%
name="success">/user/user_list.jsp</result> q`<:CfCt
</action> P9cx&Hk9
2^WJ1: A
</package> d+JK")$9C
o]e,5]
</xwork> lnZ{Ryo(
j?.F-ar
F<* / J]
1VX3pkUET
~wb1sn3
Kq")\Ha,f
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 X(N~tE
EMmgX*iu@
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 m@2E ~m
\cIN]=#
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 gpV4qDXV
EjR(AqZY
Zo3!Hs ZA
;l@94)@0
uks75W!}U
我写的一个用于分页的类,用了泛型了,hoho h:%,>I%{
d/7fJ8y8
java代码: MgJ6{xzz
cfLF@LW!])
aDbqh~7
package com.intokr.util; S>yi D`v
3B&A)&pEO
import java.util.List; Xul`>8y|
x%B_v^^^
/** v"bWVc~H
* 用于分页的类<br> T`bYidA
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ,"%C.9a
* Z,).)y#B
* @version 0.01 /s\ mV
* @author cheng }T?X6LA$I8
*/ 4era5=
public class Paginator<E> { ) O0Cz n
privateint count = 0; // 总记录数 YJJ1N/Z1
privateint p = 1; // 页编号 .a*?Pal@@
privateint num = 20; // 每页的记录数 hLO)-ueb
privateList<E> results = null; // 结果 [RyVR
;.>*O
oe&
/** \<LCp;- K
* 结果总数
w$}q`k'
*/ Nm*(?1
publicint getCount(){ ?XBdBR_"^
return count; eHphM;C
} !7N:cx'Qy
11H`WOTQF
publicvoid setCount(int count){ =L!&Z
this.count = count; :R;w<Tbz"
} s6`E.Eevm
P3zUaN\c
/** RM2Ik_IH[l
* 本结果所在的页码,从1开始 -c`xeuzK'
* w 3t,S3!
* @return Returns the pageNo. mrTf["K
*/ 6V;Dcfvi
publicint getP(){ _Id'56N]J!
return p; dN{At-
} y~9wxK
~MG6evm &
/** 42Z:J 0
* if(p<=0) p=1 |9E:S
* 5GsmBf$RUb
* @param p TDh)}Ms
*/ +IdM|4$\1
publicvoid setP(int p){ q)q3p
if(p <= 0) d<m;Q}/l&h
p = 1; uzd7v,
this.p = p; I,?NYIG"(
} %_!/4^smE
C;BO6$*_e
/** a"#t'\
* 每页记录数量 4)8k?iC*
*/ @cDB 7w\
publicint getNum(){ fv;Q*; oC&
return num; Hg#tSE
} i).%GMv*r
V+gZjuN$
/** {]CZgqE{
* if(num<1) num=1 vt
EfH
*/ 46?z*~*G
publicvoid setNum(int num){ W{,fpm
if(num < 1) Hv/C40uM-
num = 1; m<gdyY
this.num = num; }+,Q&]>~
} 1c$pz:$vX
vXJs.)D7
/** !wYN",R-
* 获得总页数 ?JuJu1
*/ CsR[@&n'
publicint getPageNum(){ mF6-f#t>H+
return(count - 1) / num + 1; ^ D0"m>3r
} 3D|Lb]=
HSruue8
/** RoqkT|#$
* 获得本页的开始编号,为 (p-1)*num+1 a*M|_&MH*
*/ !yNU-/K
publicint getStart(){ (hc!!:N~q
return(p - 1) * num + 1; N_%@_$3G]
} }e7Rpgu
F/v.hP_
/** (:iMs)
iO{
* @return Returns the results. \mb4leg5
*/ 2[lP ,;!
publicList<E> getResults(){ }?m0bM
return results; rZI63S
} }9OMXLbRv
Xu{y5N
public void setResults(List<E> results){ X9*n[ev
this.results = results; OTy!Q,0$.
} 1hbQ30
a~2Jf @I3
public String toString(){ 4 H 6t" X
StringBuilder buff = new StringBuilder h,[L6-n
rJ/HIda
(); o$@/@r
buff.append("{"); `I7s|9-=
buff.append("count:").append(count); a~KtH;7<
buff.append(",p:").append(p); IADSWzQ@
buff.append(",nump:").append(num); g~<[;6&