Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 OPY/XKyY,
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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 FFeRE{,
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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 ;v+uv f
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分页支持类: TJ[jZuT:
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java代码: :5K~/=6x
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package com.javaeye.common.util; kw^Dp[8X
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import java.util.List; T7,Gf({
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publicclass PaginationSupport { ;~:Ryl M
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publicfinalstaticint PAGESIZE = 30; .(dmuV9
) .-(-6=R
privateint pageSize = PAGESIZE; Bb[0\Hs7
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privateList items; TnBG MI,g'
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privateint totalCount; ]AC!R{H
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privateint[] indexes = newint[0]; qv*uM0G6i
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privateint startIndex = 0; ~sHZh
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public PaginationSupport(List items, int _IKP{WNB
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totalCount){ v8vh~^X%P
setPageSize(PAGESIZE); T3t~=b>&L
setTotalCount(totalCount); Ul713Bjz
setItems(items); /yw\(|T
setStartIndex(0); &8_f'+i0
} d+m6-4[_k
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public PaginationSupport(List items, int Y\g90
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totalCount, int startIndex){ -m'3L7:
setPageSize(PAGESIZE); jdg
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setTotalCount(totalCount); E#{WU}
setItems(items); i3 l #~
setStartIndex(startIndex); af?\kBm
} @Wx`l) b
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public PaginationSupport(List items, int X|1_0
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totalCount, int pageSize, int startIndex){ L >Ez-
setPageSize(pageSize); "'}v 0*[
setTotalCount(totalCount); f0mH|tI`
setItems(items);
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setStartIndex(startIndex); ;+ Co!L
} IQlw 914
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publicList getItems(){ yrE,,N%I
return items; w-'D*dOi
} _5U%'\5s
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publicvoid setItems(List items){ cdJ`Gk
this.items = items; (@WDvgi(
} cJHABdK-
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publicint getPageSize(){ -l40)^ E}
return pageSize; \o62OfF!
} SZK)q
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publicvoid setPageSize(int pageSize){ ^iV`g?z
this.pageSize = pageSize; d#vSE.&
} 94h_t@Q/1
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publicint getTotalCount(){ |`k1zc)9
return totalCount; RvPniT(<?
} PV]k3&y
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publicvoid setTotalCount(int totalCount){ X #p o|,Q
if(totalCount > 0){ G>[
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this.totalCount = totalCount; Rg8m4x w
int count = totalCount / @`IXu$Wm(
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pageSize; gI^L
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if(totalCount % pageSize > 0) n{.*El>{
count++; W?"2;](
indexes = newint[count]; kyRh k\X
for(int i = 0; i < count; i++){ ?`N57'iPb
indexes = pageSize * Fi?32e4KI5
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i; '&.)T2Kw
} R8=I)I-8
}else{ ?ae[dif
this.totalCount = 0; v9t47>V
} ^)9MzD^_nV
} .# !'c
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publicint[] getIndexes(){ ;o-\. =l
return indexes; TbKP8zw{
} "}'8`k+d
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publicvoid setIndexes(int[] indexes){ ;gxN@%}@
this.indexes = indexes; xZ.~:V03\t
} i14[3bPLk!
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publicint getStartIndex(){ 7d|*postv
return startIndex; \A'|XdQ
} /-!&k
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publicvoid setStartIndex(int startIndex){ ;NiArcAS!
if(totalCount <= 0) Ie G7@
this.startIndex = 0; `G=ztL!gq
elseif(startIndex >= totalCount) laUu"cS
this.startIndex = indexes 3bbp>7V!
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[indexes.length - 1]; rxs~y{Xi
elseif(startIndex < 0) Z&+NmOY4
this.startIndex = 0; /v}P)&
else{ w?]ZU-
this.startIndex = indexes XKz;o^1a^
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[startIndex / pageSize]; 5y1or
} kq) +@p
} !Y ;H(.A/
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publicint getNextIndex(){ Xt</ -`
int nextIndex = getStartIndex() + iGG6Myp-
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pageSize; Ujce |>Wn
if(nextIndex >= totalCount) `3f_d}b
return getStartIndex(); -Z:]<;qU
else /6+1{p
return nextIndex; !cq=)xR
} B#HV20\?v
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publicint getPreviousIndex(){ }1U#Ve,=_
int previousIndex = getStartIndex() - f,Sth7y
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pageSize; NoFs-GGGh
if(previousIndex < 0) SQq6X63 \
return0; 1^Kj8*O8e
else Yw6DJY
return previousIndex; 6B7<
} 1vB-M6(
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} $7Jfb<y
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抽象业务类 cU7rq j_
java代码: Yta1`
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/** xj0cgK|!
* Created on 2005-7-12 PV?]UUc'n<
*/ m! rwG(
package com.javaeye.common.business; F0@Qgk]\
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import java.io.Serializable; Dc5bkm
import java.util.List; U{7 3Xax
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import org.hibernate.Criteria; HH"$#T^-
import org.hibernate.HibernateException; ?QGmoQ)
import org.hibernate.Session; {*N^C@
import org.hibernate.criterion.DetachedCriteria; )8[ym/m
import org.hibernate.criterion.Projections; q\a[S*
import
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org.springframework.orm.hibernate3.HibernateCallback;
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import CV s8s
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org.springframework.orm.hibernate3.support.HibernateDaoS -g:lOht
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upport; 3AK(dC[ri
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import com.javaeye.common.util.PaginationSupport; w|=gSC-o
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public abstract class AbstractManager extends 6MuWlCKF8
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HibernateDaoSupport { Z)/6??/R
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privateboolean cacheQueries = false; \@i=)dA
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privateString queryCacheRegion; \ZS\i4
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publicvoid setCacheQueries(boolean 4RhR[
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cacheQueries){ Wdo#?@m
this.cacheQueries = cacheQueries; (zY * 0lN
} ,~- ?l7
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publicvoid setQueryCacheRegion(String )%s +?
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queryCacheRegion){ VMx%1^/(
this.queryCacheRegion = ;
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queryCacheRegion; GJX4KA8J
} Y&s2C%jT
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publicvoid save(finalObject entity){ ?yp0$r/
getHibernateTemplate().save(entity); _ENuwBYW-
} M`~!u/D7
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publicvoid persist(finalObject entity){ co/7l sW
getHibernateTemplate().save(entity); =N_,l'U\^
} 9RxO7K
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publicvoid update(finalObject entity){ k^^:;OR
getHibernateTemplate().update(entity); uArR\k(
} MHo1 lrZa+
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publicvoid delete(finalObject entity){ =D].`
getHibernateTemplate().delete(entity); ~Eq \DK
} ]M3#3Ha"
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publicObject load(finalClass entity, ]ZTcOf
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finalSerializable id){ .|uLt J
return getHibernateTemplate().load 5@ foxI
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(entity, id); kM!V.e[g
} ?>V6P_r>
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publicObject get(finalClass entity, o'Pu'y
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finalSerializable id){ 6Nt$ZYS
return getHibernateTemplate().get (;}tf~~r
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(entity, id); !%xP}{(7
} ' "'Btxz
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publicList findAll(finalClass entity){ jJ~Y]dQi
return getHibernateTemplate().find("from zE`R,:VI
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" + entity.getName()); Uki9/QiX>
} 8Bpip
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publicList findByNamedQuery(finalString .$Bwb/a
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namedQuery){ M^6$
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return getHibernateTemplate W&(f&{A
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().findByNamedQuery(namedQuery); Z)&D`RCf
} =-~;OH/
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publicList findByNamedQuery(finalString query, (R'+jWH
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finalObject parameter){ |;u}sX1t9
return getHibernateTemplate [;KmT{I9
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().findByNamedQuery(query, parameter); \dq!q=b\
} ug*D52?
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publicList findByNamedQuery(finalString query, zX kx7d8
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finalObject[] parameters){ 3]U]?h
return getHibernateTemplate by86zX
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().findByNamedQuery(query, parameters); mJC3@V
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} PJgp+u<
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publicList find(finalString query){ #tjmWGo,
return getHibernateTemplate().find t`G)b&3_O
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(query); nrpI5t.b
} M3pjXc<O
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publicList find(finalString query, finalObject *Msr15
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parameter){ 6T+
return getHibernateTemplate().find GK{{ 7B
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(query, parameter); b2kWjg.4
} z^W$%G
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public PaginationSupport findPageByCriteria )%Ru#}1X6
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(final DetachedCriteria detachedCriteria){ s_eOcm
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); |dmh
} 7@~tVxB;
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public PaginationSupport findPageByCriteria I^3:YVR&
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(final DetachedCriteria detachedCriteria, finalint Cca0](R*&
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startIndex){ _:J*Cm[q
return findPageByCriteria Z$'IBv
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(detachedCriteria, PaginationSupport.PAGESIZE, $-vo}k%M
. L;@=Yg)
startIndex); ,EEPh>cXc
} $%2H6Eg0
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public PaginationSupport findPageByCriteria 4MW ]EQ-
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(final DetachedCriteria detachedCriteria, finalint bAF )Bli
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pageSize, 'Qn~H[$/p
finalint startIndex){ KhaYr)&~
return(PaginationSupport) o-eKAkh
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getHibernateTemplate().execute(new HibernateCallback(){ orIQ~pF#
publicObject doInHibernate jo98
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(Session session)throws HibernateException { qpqokK
Criteria criteria = -5>NE35Cto
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detachedCriteria.getExecutableCriteria(session); @"|i"Hk^
int totalCount = IFuZ]CBz
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((Integer) criteria.setProjection(Projections.rowCount x?r1s#88>
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()).uniqueResult()).intValue(); >SCGK_Cr2
criteria.setProjection +=P@HfVfiq
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(null); rwqv V^
List items = 4]XI"-M^D
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criteria.setFirstResult(startIndex).setMaxResults ,&]MOe4@>
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(pageSize).list(); w+AuMc
PaginationSupport ps = dpzw.Z
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new PaginationSupport(items, totalCount, pageSize, g]$
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startIndex);
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return ps; 3|kgTB-
} 'Bq ZOZw
}, true); p1O6+hRio
} kv?|'DN
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public List findAllByCriteria(final <GIwRVCU
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DetachedCriteria detachedCriteria){ 0[a}n6XTk
return(List) getHibernateTemplate P-Su5F
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().execute(new HibernateCallback(){ /c-nE3+rn
publicObject doInHibernate ,Og4
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_ PWj(});
(Session session)throws HibernateException { ]/dVRkZeAE
Criteria criteria = TKI$hc3|L
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detachedCriteria.getExecutableCriteria(session); 8^yJqAXK
return criteria.list(); .y4&rF$n
} ?nFO:N<
}, true); "mIgs9l$
} BBL485`
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public int getCountByCriteria(final N{joXHCu
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DetachedCriteria detachedCriteria){ ;;&F1@3tBa
Integer count = (Integer) y?z\L
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getHibernateTemplate().execute(new HibernateCallback(){ XGs^rIf
publicObject doInHibernate &Cro2|KZhG
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(Session session)throws HibernateException { 1'KishHK=
Criteria criteria = YUkud2,j
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detachedCriteria.getExecutableCriteria(session); Of7+/UV
return e<\<,)9@/
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criteria.setProjection(Projections.rowCount 6m`{Z`c$
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()).uniqueResult(); OkH\^
} grcbH
}, true); >SI<rR[~%
return count.intValue(); e>H:/24
} d#_m.j
} Vb4;-?s_
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用户在web层构造查询条件detachedCriteria,和可选的 gA^q^>7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 , Ww
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PaginationSupport的实例ps。 ,E*R,'w
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ps.getItems()得到已分页好的结果集 *i%quMv
ps.getIndexes()得到分页索引的数组 Jh@_9/?
ps.getTotalCount()得到总结果数 g1[&c+=U`P
ps.getStartIndex()当前分页索引 9K"JYJ
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ps.getNextIndex()下一页索引 yp]@^T N
ps.getPreviousIndex()上一页索引 z;3NiY
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~brFo2
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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 +"!aM?o
B;t=B_oK
一下代码重构了。 E_:QSy5G
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我把原本我的做法也提供出来供大家讨论吧: u<Xog$esu
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首先,为了实现分页查询,我封装了一个Page类: .5Z_E
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java代码: D<):ZfUbI
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/*Created on 2005-4-14*/ =!0I_L/
package org.flyware.util.page; t1i(;|8|
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/** L\ j:
* @author Joa cyF4iG'M,y
* 3Sh+u>w
*/ _<Dt
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publicclass Page { 2CLB1
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/** imply if the page has previous page */ R}{GwbF_\
privateboolean hasPrePage; 0i@:KYP
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/** imply if the page has next page */ ^eh/HnJs
privateboolean hasNextPage; HnZPw&*
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/** the number of every page */ At9X]t
privateint everyPage; }T(z4P3
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/** the total page number */ *xH\)|3,
privateint totalPage; |nxdB&1n
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/** the number of current page */ v\A.Tyy
privateint currentPage; Y1\K;;X
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/** the begin index of the records by the current j\2[H^
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query */ G$=-,6kZO
privateint beginIndex; y-+G
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/** The default constructor */ ZKdh%8C
public Page(){ Sb"2Im >
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} '}{?AUDx
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/** construct the page by everyPage >BoSw&T$Q
* @param everyPage ecFi(eMD
* */ ~@9zil41
public Page(int everyPage){ F)ci9- b@
this.everyPage = everyPage; VifmZ;S@Y
} MOHHZApt
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/** The whole constructor */ v\0^mp
public Page(boolean hasPrePage, boolean hasNextPage, gGfq6{9g
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int everyPage, int totalPage, nQLs<]h1
int currentPage, int beginIndex){ HeS'~Z$
this.hasPrePage = hasPrePage; f=_g8+}h
this.hasNextPage = hasNextPage; Fd8hGj1
this.everyPage = everyPage; d*-Xuv
this.totalPage = totalPage; r+\/G{+=}
this.currentPage = currentPage; =5s$qb?#
this.beginIndex = beginIndex; 5gK~('9'?1
} Eo=HNe
o#{#r@,i
/** kL;t8{n
* @return {ymb\$f
* Returns the beginIndex. e'~ Q@_D
*/ pxplWP,
publicint getBeginIndex(){ HdCk!Fv
return beginIndex; 3$_2weZxYn
} fVUKvZ}P*
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/** hqW$kw
* @param beginIndex Xb<)LHA~3
* The beginIndex to set. 1N.tQ^
*/ cU | _
publicvoid setBeginIndex(int beginIndex){ !5.v'K'
this.beginIndex = beginIndex; ;=p;v .l
} k3yxx]Rk/
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/** zoXuFg
* @return >hb-5xC
* Returns the currentPage. @ ;J|xkJ
*/ NG)7G
publicint getCurrentPage(){ k?-S`o%Q
return currentPage; @:gl:mc
} ^[TOZXL`:
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/** (xUFl@I!
* @param currentPage ]h8/M7k
* The currentPage to set. L>:FGNf^H
*/ 7}07Pit
publicvoid setCurrentPage(int currentPage){ Sip_~]hM
this.currentPage = currentPage; NDo^B7R-
} c Vg$dt
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/** H%T3Pc
* @return )"~=7)~<^
* Returns the everyPage. V"g~q?@F
*/ R `Q?J[e
publicint getEveryPage(){ 0 r3N^_}
return everyPage; 7b,AQ9
} i n?T]}
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/** S41)l!+2
* @param everyPage f#c BQ~
* The everyPage to set. =U_@zDD@V
*/ I ,9~*^$
publicvoid setEveryPage(int everyPage){ @`2ozi~lO
this.everyPage = everyPage; ] - h|]
} c}\
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/** #VR`?n?,
* @return ]E..43
* Returns the hasNextPage. -W6V,+of
*/ hhj
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publicboolean getHasNextPage(){ gyg|Tno
return hasNextPage; 4sQ~&@[Q+
} Nc:U4
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/** qIk
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* @param hasNextPage bY&YSlO
* The hasNextPage to set. #PPsRKj3c
*/ 98 ayA$
publicvoid setHasNextPage(boolean hasNextPage){ uTUa4^]*
this.hasNextPage = hasNextPage; ]Y$&78u8t
} /gF]s_
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/** EyPy*_A
* @return i&5!9m`Cw
* Returns the hasPrePage. 9Mut p4#
*/ fl!1AKSn@N
publicboolean getHasPrePage(){ :.C)7( 8S
return hasPrePage; YFAnlqC
} 0=gF6U
ua!D-0
/** su%Z{f)#
* @param hasPrePage _"`uqW79
* The hasPrePage to set. H8x:D3C0
*/ f`bIQ 9R
publicvoid setHasPrePage(boolean hasPrePage){ )/
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this.hasPrePage = hasPrePage; 0-lPhnrp
} n*Q4G}p
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/** #C'o'%!(
* @return Returns the totalPage. YU*46 hA1B
* 5auL<Pq
*/ O]4W|WI3
publicint getTotalPage(){ #SK#k<&P
return totalPage; U8U/?zW/&
} YD dLDE
JO]`LF]
/** :v''"+\
* @param totalPage )lE3GDAPgZ
* The totalPage to set. j(UX
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*/ m|(I} |kT3
publicvoid setTotalPage(int totalPage){ !~Ax
this.totalPage = totalPage; |UABar b
} av7q>NEZ!1
Vl&+/-V
} he_HVRpB
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a [0N,t
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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 wV]sGHu F}
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个PageUtil,负责对Page对象进行构造: }u38:(^`ai
java代码: ^?81.b|qb
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/*Created on 2005-4-14*/ vK[v
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package org.flyware.util.page; U+I3 P
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import org.apache.commons.logging.Log; mNGb}
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import org.apache.commons.logging.LogFactory; m3h2/}%9`
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/** U1OLI]P
* @author Joa }6yxt9
* q{jk.:;'
*/
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publicclass PageUtil { :XNK-A W
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privatestaticfinal Log logger = LogFactory.getLog k4]R]=Fh.
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(PageUtil.class); ~`tJvUo0
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/** xP<H,og&x=
* Use the origin page to create a new page e2,<,~_K6
* @param page \emT:Frb
* @param totalRecords ;D%5 nnr
* @return \H"/2o%l")
*/ Oi+Qy[y2
publicstatic Page createPage(Page page, int Y)@oo=oG
6i*p
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totalRecords){ *m `KU+o-u
return createPage(page.getEveryPage(), Y9\]3Kno
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page.getCurrentPage(), totalRecords); 4n`[S N
} vV\/pu8
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/** _Ct@1}aa4x
* the basic page utils not including exception [rD+8,zVm
kM6
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handler i2\\!s
* @param everyPage &km d<
* @param currentPage +dPE!:
* @param totalRecords OsHkAI
* @return page {VrAh*#h
*/ Vj9`[1}1Z
publicstatic Page createPage(int everyPage, int ~7eUt^SD;
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currentPage, int totalRecords){
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everyPage = getEveryPage(everyPage); J~nJpUyP*
currentPage = getCurrentPage(currentPage); $!
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int beginIndex = getBeginIndex(everyPage, AVdd?Ew
FW6E)df
currentPage); f%(e,KgW=
int totalPage = getTotalPage(everyPage, \?p9qR;"4
yE!7`c.[u
totalRecords); Xs#?~~"aC
boolean hasNextPage = hasNextPage(currentPage, */fs.G:P
v/4X[6(
totalPage); E Ni%ge'":
boolean hasPrePage = hasPrePage(currentPage); L?/M2zc9Y
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returnnew Page(hasPrePage, hasNextPage, 'J&@jp
everyPage, totalPage, cfO^CC
currentPage, iNaC ZC
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beginIndex); yx`r;|ds}
} ]#WX|0''^
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privatestaticint getEveryPage(int everyPage){ o@Cn_p^X
return everyPage == 0 ? 10 : everyPage; R`<{W(J;r
} $`+~QR!h
FB^dp}
privatestaticint getCurrentPage(int currentPage){ {0m[:af&
return currentPage == 0 ? 1 : currentPage; E<fwl1<88
} n"Z,-./m
ES2d9/]p-
privatestaticint getBeginIndex(int everyPage, int ^b/q|(Nu&
V!aC#^
currentPage){ !x!L&p
return(currentPage - 1) * everyPage; _dRn0<#1(k
} -`ys pE0?
d$G%F $BTs
privatestaticint getTotalPage(int everyPage, int N]P*6sf-6
/:c,v-
totalRecords){ c]/O^/
int totalPage = 0; jP{]LJ2.6\
13NS*%~7[
if(totalRecords % everyPage == 0) u/c~PxC
totalPage = totalRecords / everyPage; nms<6kfzL
else +~v3D^L15
totalPage = totalRecords / everyPage + 1 ;
.ubbNp_LU
?28G6T]/?d
return totalPage; KE|u}M@v6
} Z+pvdu
+cplM5X
privatestaticboolean hasPrePage(int currentPage){ L"zgBB?K6
return currentPage == 1 ? false : true; e]y=]}A3{
} 8G^B%h]
?@uK s4
privatestaticboolean hasNextPage(int currentPage, ?PU(<A+
,`B>}
int totalPage){ -|iA!w#31
return currentPage == totalPage || totalPage == =S7C(;=4
EKJc)|8
0 ? false : true; t1_y1!uQ
} 7^Q$pT>
R~mMGz
AK\g-]8
} _ZE$\5>-
E9+O\"e9
~.y4
,-
Ss#{K;
JqV<A3i
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 J*4_|j;Z-E
yl;$#aZB
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 mjr{L{H=?+
."@a1_F|
做法如下: Y_iF$m/R
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 )<&CnK
!5
:1'$d]H
的信息,和一个结果集List: \iTPJcb5
java代码: )-Sl/G
vkauX:M
7-0twq
/*Created on 2005-6-13*/ o9SfWErZ
package com.adt.bo; UC2OYZb
KcyM2hE7
import java.util.List; u$`x]K=Zsm
,i((;/O6
import org.flyware.util.page.Page; j*lWi0Z-
0$dNrq
/** kQiW 5
* @author Joa ^=M(K ''
*/ \(7# N<-
publicclass Result { B
qiq
Ta5iY
}
private Page page; -tdON
)(
jNd&H
private List content; lSsFI30
\kRJUX!s
/** yDBgSO{d
* The default constructor u2Z^iY
*/ :s5<AT Q
public Result(){ .`8,$"`4)
super(); ?g1.-'
} :zy'hu;
thboHPml{
/** nf@u7*#6
* The constructor using fields 4!RI2?4V
* G Z[5m[
* @param page x/q$RcDOm
* @param content K OHH74}_
*/ s 17gi,"X
public Result(Page page, List content){
K`Zb;R
X
this.page = page; Kpbber
this.content = content;
l e/#J
} ?d`+vHK]>
Vt2=rD4oJk
/** <cc0 phr
* @return Returns the content. 1OwkLy,P
*/ D`@U[ `Sw
publicList getContent(){ g<5Pc,
return content; *bC^X'
} }^bL'
3 AF]en
/** <(lSNGv5N
* @return Returns the page. ?mUu(D:7D
*/ Uwil*Jh
public Page getPage(){ u\;dUnr
return page; q2pao?aa
} y:Ab5/bHy
.
zMM86 c
/** <^Nj~+G'
* @param content Wb(0Szk;
* The content to set. &\br_
*/ H/I`c>Zn
public void setContent(List content){ s3%8W==rBW
this.content = content; @*{BX~f
} Hjkgy%N
u1Yp5jp^K
/** O
lIH0
* @param page cf3c+.o
* The page to set. ;|%JvptwW%
*/ c<x6_H6[8
publicvoid setPage(Page page){ HcUz2Rm5XP
this.page = page; K1WoIv<Ym
} -KiS6$-
} uk/+
i`=
lfG's'U-z
Hmd:>_[f
+W4g:bB1
}&hgedx
2. 编写业务逻辑接口,并实现它(UserManager, "x^bl+_"
zUu>kJZ
UserManagerImpl) oU5mrS.7M!
java代码: E cz"O
\+A<s,x
EqluxD=
/*Created on 2005-7-15*/ T#f@8 -XUE
package com.adt.service; LP_F"?4
@]3Rw[%z
import net.sf.hibernate.HibernateException; e)(|
;a)\5Uy
import org.flyware.util.page.Page; @zq{#7%z
8{<cqYCR
import com.adt.bo.Result; 1uQf}
H)+kN'J
/** m%\[1|N
* @author Joa {G&g+9c&
*/ ]YzAcB.R
publicinterface UserManager { H
>{K]7D/y
?{IvA:
public Result listUser(Page page)throws Z.(x|Q9
C(Y6t1
HibernateException; /Q_\h+`
nd1*e
} ,~iAoxD5jY
0G 1o3[F
~` hcgCi%
c[7qnSH
dVfDS-v!
java代码: DyZ90]N
%Q~Lk]B?t
::` wx@
/*Created on 2005-7-15*/ :wAB"TCt0
package com.adt.service.impl; 1w^[Eno$$
(RS:_]
import java.util.List; ge8zh/`
s30_lddD
import net.sf.hibernate.HibernateException; OK}"|:hrd
F#wa)XH
import org.flyware.util.page.Page; z+I-3v
import org.flyware.util.page.PageUtil; b1o(CG(}*
!Esiq<Yh
import com.adt.bo.Result; xGA0]
_
import com.adt.dao.UserDAO; `pUArqf
import com.adt.exception.ObjectNotFoundException; 0^z$COCv
import com.adt.service.UserManager; b4ivWb |`
,&SJ?XAs
/** WG{/I/bJ_
* @author Joa d`/{0 :F
*/ 9@B+$~:}7
publicclass UserManagerImpl implements UserManager { 2[hl^f^%,
OpE+e4~IF
private UserDAO userDAO; (?[cDw/{J:
'3->G/Pu
/** N~d]}J8}gx
* @param userDAO The userDAO to set. P|U>(9;P,
*/ U?{j
publicvoid setUserDAO(UserDAO userDAO){ O=/Tx2i;
this.userDAO = userDAO; )Cl&"bX
} Vba}RF[b
W~FA9Jd'Z
/* (non-Javadoc) ](D [T
* @see com.adt.service.UserManager#listUser HfiM]^
|O?Aj1g[c?
(org.flyware.util.page.Page) &i!]
*/ )frtvN7
public Result listUser(Page page)throws A9gl|II
iz(+(M
HibernateException, ObjectNotFoundException { KK?~i[aL
int totalRecords = userDAO.getUserCount(); 9E+lriyY
if(totalRecords == 0) Gov{jksr
throw new ObjectNotFoundException B!v1gh
\m!."~%
("userNotExist"); *?+!(E
page = PageUtil.createPage(page, totalRecords); \^cn}db)
List users = userDAO.getUserByPage(page); 2<|5zF
returnnew Result(page, users); m}(DJ?qP
} G#Ow>NJ
0l6%[U?o
} ]Y?$[+Y
aRmS{X3
C*!_. <b
.Yx.Lm}
s@|?N+z
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ceCshxTU
%XeU4yg\e
询,接下来编写UserDAO的代码: hl+Yr)0\
3. UserDAO 和 UserDAOImpl: 5\J;EWTU
java代码: oSoG&4
K\q/JuDfc
4hs4W,2!
/*Created on 2005-7-15*/ SccU@3.X~
package com.adt.dao; ?*;zS%93U9
49m/UeNZ
import java.util.List; GFidriC
ov~m?Y]h
import org.flyware.util.page.Page; ~0NZx8qG
C&T3vM
import net.sf.hibernate.HibernateException; #C`!yU6(
n_<]9
/** ORoraEK
* @author Joa 5a/)|
*/ h(sD] N
publicinterface UserDAO extends BaseDAO { cPXvTVvs
JoYzC8/r
publicList getUserByName(String name)throws (ni$wjq=z^
slx^" BF^
HibernateException; u=[oo@Rk`
(2(hl--'n
publicint getUserCount()throws HibernateException; AN;?`AM;
Ub$$wOsf
publicList getUserByPage(Page page)throws h4#5j'RO
`6A"eDa
HibernateException; ]Vsze4>Z[
c2nZd.SD|
} >XF@=Jp
LHz{*`22q
L8fr
uwb
i469<^A
/iK )tl|X
java代码: G-qxQD1wK
)
l)5^7=W
jd{J3s '%
/*Created on 2005-7-15*/ ]~P?
package com.adt.dao.impl; @lX)dY
OL>/FOH:Fx
import java.util.List; '54@-}D
f
{
ueI<
import org.flyware.util.page.Page; X%dOkHarB
4*3vZ6lhu
import net.sf.hibernate.HibernateException; 2g$Wv :E3
import net.sf.hibernate.Query; O6pjuhMx
z 4-wvn<*
import com.adt.dao.UserDAO; DM&"oa50
w-2]69$k
/** JTC&_6
* @author Joa ,'j5tU?c
*/ it,%T)2H
public class UserDAOImpl extends BaseDAOHibernateImpl wKYfqNCH
?aCR>AY5X
implements UserDAO { (GV6%l#I
!EFd-fk
/* (non-Javadoc) ;kbz(:wA
* @see com.adt.dao.UserDAO#getUserByName 01Aa.i^d(
S4_Y^
(java.lang.String) o8,K1ic5#
*/ k"Is.[I?^
publicList getUserByName(String name)throws i <bs{Cu_S
gUMUh]j
HibernateException { 25(\'484>
String querySentence = "FROM user in class m0 P5a%D
}fhVn;~}8
com.adt.po.User WHERE user.name=:name"; Rz)#VVYC=
Query query = getSession().createQuery mF1oY[xa_
=Yfs=+O
(querySentence); R[V%59#{Z
query.setParameter("name", name); x.q%O1
return query.list(); W%P&o}'
} ^Ni)gm{?k
+$-a:zx`l
/* (non-Javadoc) *+IUGR
* @see com.adt.dao.UserDAO#getUserCount() 7 XY C.g
*/ YJ9_cA'A
publicint getUserCount()throws HibernateException { 5E@V@kw
int count = 0; qg O)@B+
String querySentence = "SELECT count(*) FROM Q6BWax|
-K0tK~%q
user in class com.adt.po.User"; ?`vb\K<5H;
Query query = getSession().createQuery z23KSPo
yH`xk%q_
(querySentence); SXT/9FteZ
count = ((Integer)query.iterate().next SlZu-4J.-
6Z"%vrH
()).intValue(); Wp'\NFe8
return count; D >mLSh
} ;f><;X~KX
xv2;h4{<
/* (non-Javadoc) vfj Ipg%i
* @see com.adt.dao.UserDAO#getUserByPage f|`{PP`\
uODsXi{z
(org.flyware.util.page.Page) z TK
*/ <.<Nw6
publicList getUserByPage(Page page)throws \u*,~J)z
!y),| #7P
HibernateException { %:y-"m1\u$
String querySentence = "FROM user in class YMWy5 \
{R#nGsrt;
com.adt.po.User"; IP >An8+
Query query = getSession().createQuery :!/}*B
<Z&gAqj 2
(querySentence); BoXCc"q[
query.setFirstResult(page.getBeginIndex()) %*uqtw8
.setMaxResults(page.getEveryPage()); uJWX7UGuz
return query.list(); VTHDGBU
} j7W_%Yk|E
l>G#+#{
} ;)kBJ @
2P|-V} ;9
~vXul`x
1eJ\CdI
%ry>p(-pC(
至此,一个完整的分页程序完成。前台的只需要调用 K'tz_:d|
-L[K1;Xv"
userManager.listUser(page)即可得到一个Page对象和结果集对象 A@#dv2JzP
?G{fF
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 b,'./{c0
6R<%.-qr
webwork,甚至可以直接在配置文件中指定。 }}]Y mf
F-X>|oK>z
下面给出一个webwork调用示例: & #|vGhA
java代码: 7#&sG
4qMHVPJv\
ge`J>2
/*Created on 2005-6-17*/ jm?mO9p~
package com.adt.action.user; MG<~{Y84}
X6;aF;"5
import java.util.List; EKt-C_)U
,lUo@+
import org.apache.commons.logging.Log; J]N}8 0
import org.apache.commons.logging.LogFactory; qdm!]w.G5
import org.flyware.util.page.Page; r=k}EP&<
WsoB!m
import com.adt.bo.Result; MqpoS
import com.adt.service.UserService; Nr)(&c8
import com.opensymphony.xwork.Action; 1Zecl);O{
,Q:dAe[ZsX
/** _#+9)*A
* @author Joa 5x: XXj"
*/ lC2xl( #!
publicclass ListUser implementsAction{ OU## A:gI
nYe}d!
privatestaticfinal Log logger = LogFactory.getLog |EApKxaKD
{kzM*!g
(ListUser.class); V^ :\/EU
DXiD>1(q
private UserService userService; zf!c
WX[ycm8
private Page page; qkEy$[D9
#Z.JOwi
privateList users; RS1oPY
=f["M=)ZJ
/* ,t[D1KZt
* (non-Javadoc) 5|b/G
* .3!4@l\9C
* @see com.opensymphony.xwork.Action#execute() ^J G}|v3$
*/ ks;%f34
publicString execute()throwsException{ (y36NH+
Result result = userService.listUser(page); I|M*yObl6
page = result.getPage(); >!2'|y^
users = result.getContent(); ZQ:Y5ph
return SUCCESS; 7-LeJRB
} Ac54VN
KYQ6U.%W
/** 8%"e-chd
* @return Returns the page. aJF`rLm
*/ v+OVZDf
public Page getPage(){
Bb o*
return page; 9D<HJ(
} <uvshZv
E%e-R6gl
/** d?K8Ygz
* @return Returns the users. &td#m"wI
*/ 5J;c;PF
publicList getUsers(){ s,RS}ek~|
return users; 3:gk:j#
} 5Zov<+kE
1K`A.J:Uy
/** :o:??tqw
* @param page Ef!F;D e)A
* The page to set. ]'G7(Y\)f
*/ m"DMa
publicvoid setPage(Page page){ wnX6XyUH
this.page = page; _e'mG'P(
}
Ojs\2('u
L:<'TXsRA
/** ke0W?
* @param users l0_V-|x
* The users to set. qha<.Ro
*/ H,}?YW
publicvoid setUsers(List users){ wB^a1=C
this.users = users; PjHm#a3zg%
} e#('`vGB
{
\ePJG#
/** [h1{{Nb#ez
* @param userService ?]z
._I`E
* The userService to set. 9 2EMDKJ
*/ -&?-
publicvoid setUserService(UserService userService){ /p>[$`Aq
this.userService = userService; eBB
D9SI
} U*@_T 3N
} 7d)aDc*TjW
*l//r
V?l
Go|65Z\`7M
hG^23FiN
|#wz)=mD
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 0 Yp;?p^
UU/|s>F
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 4pqZ!@45|
.tNB07=7
么只需要: *"ShE=\p
java代码: 0u_'(Z-^2
gUp0RPs
`Nn?G
<?xml version="1.0"?> msylb~ ^
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork J^:~#`8
O^#u%/
1.0//EN" "http://www.opensymphony.com/xwork/xwork- U ~m.I
zMKL: Um"
1.0.dtd"> (a?Ip)`I
fW
_.
<xwork> wk#QQDV3|0
TTpF m~?(
<package name="user" extends="webwork- ZTZE_[
bRp[N
interceptors"> ^=G+]$ 8
W=?87PkJu
<!-- The default interceptor stack name bed+Ur&
t3G'x1
--> \4k*Zk
<default-interceptor-ref wNZ7(W.U
JyO lVs<T
name="myDefaultWebStack"/> 7W"menw
BP$#a
#
<action name="listUser" "+&<Q d2
;>N ~,Q
class="com.adt.action.user.ListUser"> #4M0%rN
<param &/9oi_r%r
t^hkGYj!2
name="page.everyPage">10</param> SfUUo9R(sm
<result 3)Y:c2
<.ky1aex7
name="success">/user/user_list.jsp</result> {9
O`/|
</action> +b W|Q>u
=Qrz|$_rv
</package> OB22P%
?sYjFiE
</xwork> &v,p_'k
U@nwSfp:G
JuSS5 _&
RZA\-?cO)
@k<~`S~|
<h9\ A&
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 !$Z"\v'b
MVZ>:G9:
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。 G,*s9P]1
]?{lQ0vw'w
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 AHJ;>"]
sdQv:nd'R
1#"Q' ,7
4a!7|}W
(+dRD]|T
我写的一个用于分页的类,用了泛型了,hoho Ah{pidUx
AW5g (
java代码: JxJ ntsn
gH3kX<e
L0tKIpk
package com.intokr.util; B_glyC
oE1]vX
import java.util.List; ()?co<@(l
p)xI5,b$9
/** )7g_v*
* 用于分页的类<br> ;NE/!!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> &Q>'U6"%
* nD\os[ 3
* @version 0.01 [dlH
t;S
* @author cheng 0z7mre^Q
*/ 7"p s#)O
public class Paginator<E> { ]xEE7H]\h
privateint count = 0; // 总记录数 yuEOQ\!(u
privateint p = 1; // 页编号 p]Zabky
privateint num = 20; // 每页的记录数 tY'QQN||
privateList<E> results = null; // 结果 4&hqeY3
4uAafQ`@H
/**
"B3:m-'
* 结果总数 f*{;\n(.t
*/ 5C1Rub)
publicint getCount(){ K"j=_%{
return count; 9dtGqXX
} :iB%JY Ad
k^c=y<I
publicvoid setCount(int count){ NqE7[wH
this.count = count; ok%!o+nk.
} ;<@6f @
rq["O/2
/** O&iYGREO
* 本结果所在的页码,从1开始 G D{fXhgk
* kDY]>v
* @return Returns the pageNo. `yX+NRi(s
*/ N('DIi*or
publicint getP(){ ,9wenr
return p; R(N(@KC
} oV>AFs6
|!5T+H{Sj
/** 9w;J7jgOT!
* if(p<=0) p=1 vr;Br-8
* w })Pedg
* @param p xWz;5=7a]
*/ *jw$d8q2
publicvoid setP(int p){ Ny,A#-?
if(p <= 0) MI'l4<>u
p = 1; PJ'lZu8?x
this.p = p; V,"iMo
} 3(})uV
ivz?-X4]
/** w<>6>w@GZ
* 每页记录数量 ec4%Wk2
*/ ]!G>8Rc
publicint getNum(){ <` j[;>O
return num; 2vdQ&H4
} *a,.E6C*
i~B@(,
/** 8G l5)=2
* if(num<1) num=1 ZQ' z
*/ e$+f~~K
publicvoid setNum(int num){ a05:iFoJ
if(num < 1) *R\/#Y|
num = 1; - b\V(@5
this.num = num; |+xtFe
} ca3BJWY}J
yb{{ z@
/** d3=6MX[c
* 获得总页数 (&S[R{=^j
*/ 4Re@ QOZ
publicint getPageNum(){ q\'P1~
return(count - 1) / num + 1; JRjMt-7H_
} C:GHP$/}
wQ=yY$VP
/** ]RXtC*
* 获得本页的开始编号,为 (p-1)*num+1 K*U=;*p)
*/ P[I*%
publicint getStart(){ d?&!y]RS#
return(p - 1) * num + 1; ?I2k6%a
} h9BD
^j
eIUuq&(
/** i=X*
* @return Returns the results. w^rb|mKo
*/ |;U=YRi
publicList<E> getResults(){ 2u*h*/
return results; B?lBO
V4v4
} g3~~"`2
lc3S|4
public void setResults(List<E> results){ OT}Yr9h4
this.results = results; O`[iz/7m
} 2VV[*QI
,KhMzE8_a
public String toString(){ B==a
StringBuilder buff = new StringBuilder tk)>CK11
|IX` (
(); 2^^'t 6@
buff.append("{"); [[?[? V ,
buff.append("count:").append(count); L>~@9a\jO
buff.append(",p:").append(p); 4&oXy,8LC
buff.append(",nump:").append(num); ,+\4
'`
buff.append(",results:").append *0&4mi8
2 ]DCF
(results); eN|HJ=
buff.append("}"); `b.o&t$L
return buff.toString(); qaMZfA
} 2c"N-c&A
[Zt#
c C+
} &J;H@d||
Cwsoz
x ?f0Hk+