Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 `wG&Cy]v
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 N=L
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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 17qrBG-/MD
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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 ')FNudsC
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分页支持类:
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java代码: !8s:3]
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package com.javaeye.common.util; @fYA{-ZC
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import java.util.List; ?
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publicclass PaginationSupport { s^v,i
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publicfinalstaticint PAGESIZE = 30; p0YTZS ]h
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privateint pageSize = PAGESIZE; wLUmRo56aR
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privateList items; 3i$AR
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privateint totalCount; (c*Dvpo1
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privateint[] indexes = newint[0]; )*JTxMQ
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privateint startIndex = 0; ?x/L"h&Kp
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public PaginationSupport(List items, int F^~#D, \
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totalCount){ n*xNMw1x"T
setPageSize(PAGESIZE); a:]yFi:Su
setTotalCount(totalCount); Zj<T#4?8
setItems(items); Q\z*q,^R
setStartIndex(0); |Z/ySAFM
} &boBu^,94
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public PaginationSupport(List items, int (6+0U1[Iz
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totalCount, int startIndex){ J8D-a!
setPageSize(PAGESIZE); +[7u>RJ
setTotalCount(totalCount); K^vMIo h
setItems(items); z'I0UB#
setStartIndex(startIndex); NV;tsuA|
} \^:f4ZT
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public PaginationSupport(List items, int
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totalCount, int pageSize, int startIndex){ ?k?Hp:8?=
setPageSize(pageSize); s`2o\]
setTotalCount(totalCount); zc(7p;w#p
setItems(items); xMh&C{q
setStartIndex(startIndex); cS[`1y,\3
} 0nuFWV
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publicList getItems(){ 5VcYdu3
return items; ']NM_0
} O#|E7;
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publicvoid setItems(List items){ pQ hv3F
this.items = items; GgYomR:
} }?^G=IP4(
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publicint getPageSize(){ DQ}]'*@?
return pageSize; iB`m!g6$
} oAx0$]+%V)
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publicvoid setPageSize(int pageSize){ ] ge-b\
this.pageSize = pageSize; `F@yZ4L3S
} M/qiA.C@W
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publicint getTotalCount(){ lo#,zd~
return totalCount; IR&u55#I6
} PTh
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publicvoid setTotalCount(int totalCount){ ^eRuj)$5A
if(totalCount > 0){ WveFB%@`;
this.totalCount = totalCount; 1,J.
int count = totalCount / x@ O:
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pageSize; }R x%&29&
if(totalCount % pageSize > 0) {%Y7]*D
count++; ;sf/tX
indexes = newint[count]; +A3H#'
for(int i = 0; i < count; i++){ a*8}~p,
indexes = pageSize * ;FBc^*q
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} 1d"P) 3dQ
}else{ qG qu/$bh
this.totalCount = 0; '9gI=/29D
} 9lxT5Wg
} .%A2
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publicint[] getIndexes(){ SJ-Sac58r
return indexes; ]lY9[~
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} loJ0PY'}=
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publicvoid setIndexes(int[] indexes){ DPOPRi~
this.indexes = indexes; Ah`dt8t
} 4@I]PG
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publicint getStartIndex(){ K36B9<F
return startIndex; g]#Wve
} _;{-w%Vf
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publicvoid setStartIndex(int startIndex){ gib]#n1!p
if(totalCount <= 0) 2'U9!.o
this.startIndex = 0; i.] zq
elseif(startIndex >= totalCount) 'Ot[q^,KRG
this.startIndex = indexes l?o-
p
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[indexes.length - 1]; Izu.I_$4
elseif(startIndex < 0) %K7}yy&9C
this.startIndex = 0; cw.7YiU
else{ (% P=#vZ
this.startIndex = indexes Ev16xL8B
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[startIndex / pageSize]; I\~V0<"jI
} *zWn4BckN
} 'r%oOZk)z
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publicint getNextIndex(){ v2{s2kB=
int nextIndex = getStartIndex() + sh2bhv]
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pageSize; vNbA/sM
if(nextIndex >= totalCount) mtHz6+
return getStartIndex(); $@)d9u
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else HV.7IyBA^
return nextIndex; X;:xGZ-oY
} +kL(lBv'
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publicint getPreviousIndex(){ <4,?lZ
int previousIndex = getStartIndex() - }o-P
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pageSize;
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if(previousIndex < 0) w)n]}k
return0; z%tu6_4j
else 'wrpW#
return previousIndex; tqCg<NH.!m
} [@Y q^.6t
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} /p0LtUMu
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抽象业务类 8zWPb
java代码: [Gy'0P(EQ
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/** iGLYM-
* Created on 2005-7-12 -d'|X`^nE
*/ {2r7:nvR
package com.javaeye.common.business; P*Sip?tdE
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import java.io.Serializable; FaE orQ
import java.util.List; g"S+V#R
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import org.hibernate.Criteria; T(^8ki
import org.hibernate.HibernateException; gq3OCA!cX
import org.hibernate.Session; GuvF
import org.hibernate.criterion.DetachedCriteria; |LE++t*X~
import org.hibernate.criterion.Projections; GQq'~Lr5
import e622{dfVS
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org.springframework.orm.hibernate3.HibernateCallback; lG>e6[Wc
import ^\jX5)2{
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org.springframework.orm.hibernate3.support.HibernateDaoS 4CT9-2UC
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upport; S=SncMO nE
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import com.javaeye.common.util.PaginationSupport; bGc|SF<V
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public abstract class AbstractManager extends Lu.tRZ`$38
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HibernateDaoSupport { >[4|6k|\x
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privateboolean cacheQueries = false; fcXk]W
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privateString queryCacheRegion; _)2TLA
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publicvoid setCacheQueries(boolean hpV
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cacheQueries){ G;c0
this.cacheQueries = cacheQueries; 6RQCKN)
} k+GnF00N^8
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publicvoid setQueryCacheRegion(String <SdJM1%Qo
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queryCacheRegion){ {eN{Zh5"
this.queryCacheRegion = FKnQwX.0
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queryCacheRegion; 1";e'?^x
} SliQwm5
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publicvoid save(finalObject entity){ iiB )/~!O
getHibernateTemplate().save(entity); ^i)Q
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} '4lT*KN7\
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publicvoid persist(finalObject entity){ /M*\t.[ 46
getHibernateTemplate().save(entity); 8;f<q u|w
} PG[O?l
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publicvoid update(finalObject entity){ @<TZH
getHibernateTemplate().update(entity); {&u7kWD|
} T^;Jz!e
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); UJ)M:~O
} u m2s^G
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publicObject load(finalClass entity, AnE_<sPA
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finalSerializable id){ qs1.@l("
return getHibernateTemplate().load )/T$H|
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(entity, id); ~K$"PKs3
} 7cP[o+
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publicObject get(finalClass entity, G[<[#$(
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finalSerializable id){ f(s3TLM
return getHibernateTemplate().get K-k.=6mS
],}afa!A
(entity, id); S]%U]
} sa(M66KkU
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publicList findAll(finalClass entity){ o7a6 )2JK
return getHibernateTemplate().find("from +IO1ipc4cE
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" + entity.getName()); +6M+hO]
} 0H&U=9'YT
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publicList findByNamedQuery(finalString 2DCcGKa"
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namedQuery){ ivUsMhx>S,
return getHibernateTemplate !0csNg!
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().findByNamedQuery(namedQuery); $aPHl
} [gh[F
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publicList findByNamedQuery(finalString query, KkL:p?@n
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finalObject parameter){ nL(%&z \4
return getHibernateTemplate +b,31
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().findByNamedQuery(query, parameter); ~UJu
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} <,4R2'
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publicList findByNamedQuery(finalString query, fov=Yd!
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finalObject[] parameters){ Q#ZD&RZ9.
return getHibernateTemplate Wt)SdF=U/
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().findByNamedQuery(query, parameters); ZOrTbik
} @U
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publicList find(finalString query){
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return getHibernateTemplate().find ZYA.1VrM
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(query); 'D0X?2
} R|)2Dg
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publicList find(finalString query, finalObject KIAe36.~
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parameter){ e9Ul A
return getHibernateTemplate().find Il^\3T+
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(query, parameter); s{z~Axup-
} oLqbR?
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public PaginationSupport findPageByCriteria !,6v=n[Nz
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(final DetachedCriteria detachedCriteria){ Y7:Y{7E7
return findPageByCriteria +{C9uY)$vf
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); fr'huvc
} Hr<C2p^a
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public PaginationSupport findPageByCriteria io9xI3{
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(final DetachedCriteria detachedCriteria, finalint `Ge +(1x
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startIndex){ >Z2,^5P{
return findPageByCriteria Rgfc29(8
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(detachedCriteria, PaginationSupport.PAGESIZE, D-o7yc"K
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startIndex); jI{~s]Q
} /[20e1 w!
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public PaginationSupport findPageByCriteria (
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(final DetachedCriteria detachedCriteria, finalint e:$7^Y,U/
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pageSize, %7NsBR!y
finalint startIndex){ W<rTq0~$?
return(PaginationSupport) !O F?xW
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getHibernateTemplate().execute(new HibernateCallback(){ h"PS-]:CD
publicObject doInHibernate f
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(Session session)throws HibernateException { WG8iTVwx
Criteria criteria = tIyuzc~U
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detachedCriteria.getExecutableCriteria(session); ];pf
int totalCount = p- "Z'$A`
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((Integer) criteria.setProjection(Projections.rowCount zmB31' _
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()).uniqueResult()).intValue(); [:nx);\
criteria.setProjection ^zaKO'KcV
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(null); H:q )^$s
List items = a@fE46o6<
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criteria.setFirstResult(startIndex).setMaxResults pK6e/eC
m feMmKFu\
(pageSize).list(); HBh` 2Q
PaginationSupport ps = ggm2%|?X
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new PaginationSupport(items, totalCount, pageSize, e}'#Xv
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startIndex); cS D._"P
return ps; ocIt@#20K
} #cj\~T.,,
}, true); .1.J5>/n
} 9^ >M>f"
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public List findAllByCriteria(final fJ)N:q`
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DetachedCriteria detachedCriteria){
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return(List) getHibernateTemplate 0T9@,scY
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().execute(new HibernateCallback(){ ;dqk@@O"(
publicObject doInHibernate J Q)4}t
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(Session session)throws HibernateException { yaH
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Criteria criteria = >aEL;V=}P
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detachedCriteria.getExecutableCriteria(session); dSOlD/c
return criteria.list(); 6X@mPj[/
} 10C 2=
}, true); ;YK!EMM4!h
} Aautih@LX
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public int getCountByCriteria(final Ni2]6U
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DetachedCriteria detachedCriteria){ ,c4c@|Bh?
Integer count = (Integer) "El^38Ho
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getHibernateTemplate().execute(new HibernateCallback(){ v!NB~"LQ
publicObject doInHibernate uP{;*E3?
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(Session session)throws HibernateException { rQ9*J
Criteria criteria = )!'n&UxPo$
)\{'fF
detachedCriteria.getExecutableCriteria(session); ss?]
return m"lE&AM64p
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criteria.setProjection(Projections.rowCount #*!+b
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()).uniqueResult(); F,*2#:Ki
} z 0~j
}, true); x}tKewdOSe
return count.intValue(); <jbj/Q )"
} Wgxn`6
} / Zo~1q
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用户在web层构造查询条件detachedCriteria,和可选的 :e1'o
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Da"yZ\4
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PaginationSupport的实例ps。 *;<e
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ps.getItems()得到已分页好的结果集 6fh{lx>
ps.getIndexes()得到分页索引的数组 yZq?B
ps.getTotalCount()得到总结果数 LO"_NeuL
ps.getStartIndex()当前分页索引 B;VH `*+X
ps.getNextIndex()下一页索引 >&bv\R/
ps.getPreviousIndex()上一页索引 )T>8XCL\}
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Z.!g9fi8>
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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 brb[})}
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一下代码重构了。 f%c06Un=
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我把原本我的做法也提供出来供大家讨论吧: BsKbn@'uC
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首先,为了实现分页查询,我封装了一个Page类: Hw Z^D=A
java代码: 0z/h+,
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/*Created on 2005-4-14*/ Zp`~}LV{
package org.flyware.util.page; .N5'.3
S#k{e72 *
/** .>P~uZiX!
* @author Joa !~WZ_z
* C5Xof|#p|
*/ h%'
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publicclass Page { ?4,@,
ae&
5? Wg%@
/** imply if the page has previous page */ cST\~SUm
privateboolean hasPrePage; >;,gGH
ei@3,{~5
/** imply if the page has next page */ A^-iHm
privateboolean hasNextPage; W+8^P(
K
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/** the number of every page */ TM0b-W (H
privateint everyPage; 6#E7!-u(-
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/** the total page number */ aVP5%
privateint totalPage; ,(P %z.P@
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/** the number of current page */ wS V@=)H\:
privateint currentPage;
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/** the begin index of the records by the current x@Y|v@}BE
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query */ D i+4Eb
privateint beginIndex; 0pD[7~ ^o
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/** The default constructor */ F99A;M8(
public Page(){ g92dw<$>
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} yxvjg\!&
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/** construct the page by everyPage `NQ{)N0!
* @param everyPage DcN"=Y
* */ 'j }g
public Page(int everyPage){ ehE-SrkU'
this.everyPage = everyPage; -,^WaB7u\
} uoHqL IpQ
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/** The whole constructor */ eES'}[W>
public Page(boolean hasPrePage, boolean hasNextPage, as(*B-_n~
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int everyPage, int totalPage, G,]z(%
int currentPage, int beginIndex){ bEd?^h
this.hasPrePage = hasPrePage; zks#EzQ
this.hasNextPage = hasNextPage; ;,rnk-
this.everyPage = everyPage; d@ZoV
this.totalPage = totalPage; /ERNS/w
this.currentPage = currentPage; !R74J=#(
this.beginIndex = beginIndex; ?I[h~vr6.
} ^!}F%
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/** Ihg~Q4t
* @return ra]:$XJ5=a
* Returns the beginIndex. %K?iNe
*/ .fEwk
publicint getBeginIndex(){ Ukc'?p,*
return beginIndex; <(YF5Xm6$h
} FZ p<|t
n'?4.tb
/** "y$ qrN-
* @param beginIndex A#35]V06
* The beginIndex to set. p![&8i@ym
*/ vU}: U)S
publicvoid setBeginIndex(int beginIndex){ $ 6!iBX@
this.beginIndex = beginIndex; `VZZ^K9zR
} C`0%C7
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/** VjB*{,
* @return kwlC[G$j7
* Returns the currentPage. #V[SQ=>x[
*/ | ]# +v@
publicint getCurrentPage(){ uoCGSXsi
return currentPage; Szts<n5
} E*k([ZL
TV=c,*TV
/** K2HvI7$-
* @param currentPage s@~/x5jwCs
* The currentPage to set. hJ[UB
*/ N@()F&e
publicvoid setCurrentPage(int currentPage){ o,FUfO}F
this.currentPage = currentPage; G3dhM#!
} 1Nj=B_T
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/** o?wt$j-
* @return ln#\sA?iG
* Returns the everyPage. &SmXI5>Bo0
*/ U:n*<l-k}
publicint getEveryPage(){ EkZjO Ci
return everyPage; wAh#
} zQc"bcif5(
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/** OQFi.8
* @param everyPage a5?A!k\2
* The everyPage to set. B{aU;{1
*/ W-XpJ\_
publicvoid setEveryPage(int everyPage){ ffk4mhH
this.everyPage = everyPage; wyw <jH
} tS<h8g_
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/** nY0sb8lZJ
* @return hVUIBJ/5(-
* Returns the hasNextPage. WNF9#oN|oT
*/ $XGtS$
publicboolean getHasNextPage(){ iBoEZEHjw
return hasNextPage; <hv7s,i
} lFfXWNb
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/** e$|VG*
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* @param hasNextPage o&$hYy"<.L
* The hasNextPage to set. fHfY}BQS
*/ 2~FPw{]j
publicvoid setHasNextPage(boolean hasNextPage){ |I^y0Q:K
this.hasNextPage = hasNextPage; !SF^a6jT
} J8;Okzb!L
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/** fxtxu?A>
* @return o56kp3b)b
* Returns the hasPrePage. w$>3pQ8d
*/
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publicboolean getHasPrePage(){ 3cC }'j
return hasPrePage; 1[DS'S
} UX_I6_&
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/** ?"j@;/=
* @param hasPrePage 9":2"<'+
* The hasPrePage to set. #ElejQ|?
*/ uD(t`W"
publicvoid setHasPrePage(boolean hasPrePage){ "EH,J
this.hasPrePage = hasPrePage; FkB{ SCJ
} 1;Xgc@
m r4b
/** "'A"U
* @return Returns the totalPage. dJl^ADX[@
* ({M?Q>s
*/ %
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publicint getTotalPage(){ RrWNJ&o
return totalPage;
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} JJ5C}`(
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/** z*LiweR-
* @param totalPage cNj*E
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* The totalPage to set. io4aYB\
*/ &Rp"rMeW
publicvoid setTotalPage(int totalPage){ -t4
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this.totalPage = totalPage; 1TRN~#ix
} [/ohk&
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} #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 nbxR"UH
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个PageUtil,负责对Page对象进行构造: c3k|G<C2
java代码: NHkL24ve
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/*Created on 2005-4-14*/ / L~u02?
package org.flyware.util.page;
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import org.apache.commons.logging.Log; G$5m$\K
import org.apache.commons.logging.LogFactory; ]W)
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/** GDPo`#~
* @author Joa FFe)e>bH
* SLoo:)
*/ rAXX}"l6s
publicclass PageUtil { |Td5l?
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privatestaticfinal Log logger = LogFactory.getLog g-@h>$<
1
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(PageUtil.class); r(`nt-o@
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/** cwynd=^nC
* Use the origin page to create a new page %EI<@Ps8c
* @param page DU{bonR`
* @param totalRecords @
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* @return ZnXejpj)D
*/ N[k<@Q?*a
publicstatic Page createPage(Page page, int vv/J 5#^,\
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totalRecords){ 4P kfUMX
return createPage(page.getEveryPage(), qtzRCA!9(Z
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page.getCurrentPage(), totalRecords); 2p:r`THvS5
} ;V.vfar
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/** !T'X
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* the basic page utils not including exception 0"4@;e_)>
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handler wUp)JI
* @param everyPage P*G+eqX
* @param currentPage zWIeHIt
* @param totalRecords RP`
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* @return page ?_ RYqolz
*/ ek)Xrp:2
publicstatic Page createPage(int everyPage, int 6/2v
x /
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currentPage, int totalRecords){ \6sQJq
everyPage = getEveryPage(everyPage); slvq9,
currentPage = getCurrentPage(currentPage); 'b[0ci:
int beginIndex = getBeginIndex(everyPage, #*,sa
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currentPage); Y<LNQ]8\G
int totalPage = getTotalPage(everyPage, h&'=F)5
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totalRecords); O&$0&dhc
boolean hasNextPage = hasNextPage(currentPage, Iql5T#K+
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totalPage); |E|6=%^
boolean hasPrePage = hasPrePage(currentPage); SS8ocGX
3"rkko?A
returnnew Page(hasPrePage, hasNextPage, Lk.h.ST
everyPage, totalPage, 7BFN|S_l
currentPage, agsISu(
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beginIndex); _t-7$d"
} f a5]a
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privatestaticint getEveryPage(int everyPage){ aWaw&u
return everyPage == 0 ? 10 : everyPage; Rd! 2\|
} b5 Q NEi
\Ph7(ik
privatestaticint getCurrentPage(int currentPage){ C\Ayv)S#2
return currentPage == 0 ? 1 : currentPage; W_<4WG
} iBvOJs
ty-
r&
privatestaticint getBeginIndex(int everyPage, int y/R+$h(%
0.DQO;
currentPage){ K]"Kf{bx
return(currentPage - 1) * everyPage; Tf-CEHWD
} <abKiXA"
-p8e
privatestaticint getTotalPage(int everyPage, int ~A >oO-0K
)H+kB<n
totalRecords){ t[2i$%NVM
int totalPage = 0; XxOn3i
)Au&kd-W@(
if(totalRecords % everyPage == 0) B8~=RmWLl
totalPage = totalRecords / everyPage; yJ/#"z=h?
else #s+Q{2s
totalPage = totalRecords / everyPage + 1 ; %#k,6;m
6tdI6
return totalPage; $Jf9;.
} r/AHJU3&eY
}ND'0*#
privatestaticboolean hasPrePage(int currentPage){ ")M;+<c"l
return currentPage == 1 ? false : true; ;[Tyt[
} \ X$)vK
{L9yhYw
privatestaticboolean hasNextPage(int currentPage, j>!sN`dBj
Kbas-</Si
int totalPage){ "DjU:*'
return currentPage == totalPage || totalPage == =Ahw%`/&}]
v*r9j8
0 ? false : true; Z[}
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} "$8w.C
&;v!oe
;BI)n]L
} s*JE)
3qo e^e
k18$JyaG
e&3#2_
X47O l
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。 3w'W~
Jz$>k$!UD
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 Yu3_=:
<C
k/#>S*Ne
做法如下: u(hC^T1
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 263*: Y
btQet.
的信息,和一个结果集List: N!m%~kS9k<
java代码: T
% /
%F5 =n"
,so4Lb(vG
/*Created on 2005-6-13*/ !}q."%%J_%
package com.adt.bo; rzV"Dm$'
7bT
/KLU
import java.util.List; F^rl$#pCS
AgsR-"uh
import org.flyware.util.page.Page; Zh,]J `
p&5S|![\
/** EUZq$@uWL
* @author Joa bp%S62Dj
*/ J @B4
R&V
publicclass Result { k4R4YI"jV
-S$$/sR
private Page page; ,}<RrUfD
76cEKHa<
private List content; -+P7:4/
.)`-Hkxa
/** F< |c4
* The default constructor *?N<S$m
*/ a#QByP
public Result(){ }+DDJ6Jzs
super(); C1 {ZW~"YI
} xid:" y=_&
T} 8CfG_j
/** <gcmsiB|
* The constructor using fields o)!m$Q~v
* #=x+
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* @param page & rQD `E/
* @param content |EeBSRAfe
*/ wlVvxX3%
public Result(Page page, List content){ BWEv1' v
this.page = page; sVoR?peQ
this.content = content; :;TYL[
} ]xrD<
:c<*%*e
/** SG`)PW?
* @return Returns the content. #eLN1q&Z
*/ OPiaG!3<
publicList getContent(){ ,s? dAy5
return content; Ff)@L-Y\K
} P;c0L;/
(H-cDsh;c
/** {]["6V6W
* @return Returns the page. R&!]Rl9hf
*/ +-P<CCvWz
public Page getPage(){ i[_|%'p
return page; o=mo/N4
} wA",SBGX
y.ql#eQ,
/** .C?GW1[c~@
* @param content 4d-q!lR pa
* The content to set. :<UtHf<=k
*/ 4k$0CbHx0
public void setContent(List content){ 97]4
:Zv
this.content = content; os_WYQ4>j
} LYNZP4(R
@<5Tba>SC
/** sDAK\#z
* @param page d<v~=
* The page to set. sMX$Q45e
*/ en%B>]QI
publicvoid setPage(Page page){ J7m`]!*t
this.page = page; ?\M)WDO
} 0Jg+sUs{
} SS0_P
jKz
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K=o:V&
AZBC P
.5z&CJDiIi
2. 编写业务逻辑接口,并实现它(UserManager, i*z0Jf["
8~qlLa>jc
UserManagerImpl) ^k;mn-0
java代码: %yKKUZ~
_'lmCj8L
UEN56@eCNf
/*Created on 2005-7-15*/ RxMoD.kx
package com.adt.service; `x*/UCy\
KcnjF^k
import net.sf.hibernate.HibernateException; 94YA2_f;
3 69Zu4|u
import org.flyware.util.page.Page; L}b'+Wi@
b?>VPuyBb
import com.adt.bo.Result; )r pD2H
{s9<ej~<R
/** \H[Yyp4
* @author Joa M#T#:wf~
*/ qzHU)Ns(_
publicinterface UserManager { FSe5k5
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public Result listUser(Page page)throws 7P
c(<Ui+
{yU0D*#6
HibernateException; cTy'JT7
=G*z
53
} :i}@Br+R7L
aC}p^Nkr"k
s" N\82z)
Ta^.$O=F
2;h+;G
java代码: MU*It"@}2
cPSti
:-U53}Iy
/*Created on 2005-7-15*/ tStJ2-5*t
package com.adt.service.impl; ]6q*)q:`
Qqh^E_O
import java.util.List; k1m'Ka-
^} tuP
import net.sf.hibernate.HibernateException; s*eyTm
Z) t{JHm:
import org.flyware.util.page.Page; #:Xa'D+
import org.flyware.util.page.PageUtil; Z]7tjRvq)
] .`_,
IO
import com.adt.bo.Result; {H'X)n$
import com.adt.dao.UserDAO; 5DUi4 Cbgy
import com.adt.exception.ObjectNotFoundException; qNy-o\;XN
import com.adt.service.UserManager; `}Eh[EOHJ
lj
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/** #'wL\3
* @author Joa @H6%G>K,
*/ m$)YYpX
publicclass UserManagerImpl implements UserManager { vv!Bo~L1,
8ZFH}v@V1'
private UserDAO userDAO; shD+eHo$
_=6vW^s
/** Agz=8=S%
* @param userDAO The userDAO to set. IE|,~M2
*/ fmBkB8
publicvoid setUserDAO(UserDAO userDAO){ 9V.+U7\w
this.userDAO = userDAO; /K[]B]1NE
} ^SgN(-QH
$.;iu2iyo
/* (non-Javadoc) K('
9l& A
* @see com.adt.service.UserManager#listUser vWuyft*
y]w )`}Ax
(org.flyware.util.page.Page) ~RAzFLt6x
*/ $Q=$?>4U
public Result listUser(Page page)throws :ET x*c
8pd&3G+
HibernateException, ObjectNotFoundException { ?S8$5gA
int totalRecords = userDAO.getUserCount(); v,8Si'"i+
if(totalRecords == 0) kF#{An)P
throw new ObjectNotFoundException M *v^N]>"G
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("userNotExist");
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page = PageUtil.createPage(page, totalRecords); pTN%;`)
{
List users = userDAO.getUserByPage(page); xS-w\vbLV
returnnew Result(page, users); !eV^Ah>PZ
} Zi
ma^IL
4bE42c=Ca7
} ]bf'
x4@MO|C
Cy]"
a$A2IkD
Oxpo6G
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 58 kv#;j
2lF WW(
询,接下来编写UserDAO的代码: A (PE
3. UserDAO 和 UserDAOImpl: n&(3o6i'
java代码: 0=2H9v
SCqu,
Rz)v-Yu
/*Created on 2005-7-15*/ cl?<
7
package com.adt.dao; =7#u+*Yr9
y(V&z"wk[
import java.util.List; B$@1QG
.v N)A
*
import org.flyware.util.page.Page; uQO(?nCi
uwmoM>I W^
import net.sf.hibernate.HibernateException; 6Q?BwD+>
:vw0r`
/** cn@03&dAl
* @author Joa c]S+70!n
*/ U<K|jsFo
publicinterface UserDAO extends BaseDAO { *Rz!i m|
jQO*oq}
publicList getUserByName(String name)throws pHigxeV2
u<$S>
HibernateException; /5&3WG&<u
E*Pz <
publicint getUserCount()throws HibernateException; | pF5`dX
7k.d|<mRv
publicList getUserByPage(Page page)throws ]6jHIk|
&t[z
HibernateException; N'htcC
f34_?F<h
} ?f(pQy@V
~JIywzcf8
bX a %EMF
=PI^X\if88
>hHJ:5y
java代码: 3| GNi~
,w,ENU0~f
^qE<yn
/*Created on 2005-7-15*/ '#;,oX~5
package com.adt.dao.impl; cdd P
T
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import java.util.List; 4x=V|"
Pn~pej5'K
import org.flyware.util.page.Page; p7%0hLW
nh _DEPMq
import net.sf.hibernate.HibernateException; Ry3+/]
import net.sf.hibernate.Query; :!r9 =N9
Bu*W1w\
import com.adt.dao.UserDAO; a7ub.9>
EGp~Vo-
/** WZfk}To1#
* @author Joa }|w=7^1z
*/ Oex{:dO "F
public class UserDAOImpl extends BaseDAOHibernateImpl |#Yu.c*
eD>-`'7<
implements UserDAO { } S'I
DHla
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/* (non-Javadoc) 6n2Vx1b
* @see com.adt.dao.UserDAO#getUserByName _C7abw-
n's2/9x
(java.lang.String) (OM?aW
*/ .6lY*LI
publicList getUserByName(String name)throws Y&ct+w]%
MAm1w'ol"
HibernateException { oO! 1
String querySentence = "FROM user in class (mD-FR@#
/\IAr,w[
com.adt.po.User WHERE user.name=:name";
z*??YUT\M
Query query = getSession().createQuery X
,V= od>
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(querySentence); U89]?^|bb
query.setParameter("name", name); .0R/'!e
return query.list(); Y yQf
} BN<#x@m$]
V0SW 5
m
/* (non-Javadoc) =)"NE>
* @see com.adt.dao.UserDAO#getUserCount() |TQedC
*/ 3&drof\{
publicint getUserCount()throws HibernateException { g]EQ2g_N1
int count = 0; 6xDl=*&%
String querySentence = "SELECT count(*) FROM sRo<4U0M;l
];d5X
user in class com.adt.po.User"; i_oro"%yL
Query query = getSession().createQuery lOowMlf@2
F^ %{
;
(querySentence); w@gl
count = ((Integer)query.iterate().next `? 9]'
f)u*Q!BDD
()).intValue(); %x cM_|AyR
return count; zm;*:]S
}
s+y'<88
}iiG$?|.
/* (non-Javadoc) ne!j%9Ar
* @see com.adt.dao.UserDAO#getUserByPage 7gZVg@
q/ d5P
(org.flyware.util.page.Page) 1pYmtr
*/ 0`g}(}'L
publicList getUserByPage(Page page)throws T@d_t
|p=.Gg=2
HibernateException { $v?! 6:
String querySentence = "FROM user in class ,J`lr
U0
@4 Os?_gJ\
com.adt.po.User"; -N-4l
Query query = getSession().createQuery ulz\x2[Pf
c'TiWZP~
(querySentence); Y*5@|Q
query.setFirstResult(page.getBeginIndex()) M&}oat*
.setMaxResults(page.getEveryPage()); _!$Up
return query.list(); Z;"4$@|qE
} ^w&5@3d
x3Dg%=R
} }v'PY/d.
a@S4IoBg%
#(26t _a
rH2tC=%
C>k;Mvq O
至此,一个完整的分页程序完成。前台的只需要调用 BRSgB-Rr7
XEgx#F ;F
userManager.listUser(page)即可得到一个Page对象和结果集对象 Im' :sJ31
*$4A|EA V
的综合体,而传入的参数page对象则可以由前台传入,如果用 k_En_\c?p2
>H=Q$gI
webwork,甚至可以直接在配置文件中指定。 %1 VNP(E
5 vu_D^Q
下面给出一个webwork调用示例: [#P`_hx
java代码: =?`y(k4a
cc2 oFn
H>X\C;X[
/*Created on 2005-6-17*/ Jegx[*O>b
package com.adt.action.user; yG4LQE
+qSr=Y:+
import java.util.List; #0YzPMV
Ck/_UY|
import org.apache.commons.logging.Log; &)"7am(S`
import org.apache.commons.logging.LogFactory; nM (=bEX
import org.flyware.util.page.Page; cV=_GE
_A~~L6C
import com.adt.bo.Result; }G,SqpcG
import com.adt.service.UserService; @6i8RmOu}
import com.opensymphony.xwork.Action; &=6cz$]z
wE8a4.
/** /F8\%l+
* @author Joa xJF6l!`
*/ \$~oH3m&
publicclass ListUser implementsAction{ 0imqj7L
wTMHoU*>
privatestaticfinal Log logger = LogFactory.getLog G|6 |;
Ae{4AZ
(ListUser.class); W_f"Gk
"6*Kgf2G
private UserService userService; yOn2}Z
8NF;k5
private Page page; ttAVB{kdo
hiK[!9r
privateList users; G(|(y=ck
EkB6- nz
/* `S/1U87
* (non-Javadoc) eM1;Nl
* OL
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* @see com.opensymphony.xwork.Action#execute() )zL"r8si
*/ XB!`*vZ/<
publicString execute()throwsException{ \Zz= 4
j
Result result = userService.listUser(page); 8a$jO+UvN
page = result.getPage(); {GH`V}Ob
users = result.getContent(); 7L~ zI>2
return SUCCESS; h7W%}6Cqkw
} i37a}.;
]stLC; nI
/** g`5`KU|
* @return Returns the page. W|-N>,G
*/ X^_+%U
public Page getPage(){ 2Fp]S
a
return page; d`],l\oC
} {+UNjKQC
4pTuP /
/** hZ\W ?r
* @return Returns the users. <sWcS; x
*/ @tv];t
publicList getUsers(){ 8hdAXWPn
return users; {@K2WB
} xMfv&q=k@
b=QGbFf
/** 6`5
@E\"E
* @param page #ZnX6=;X
* The page to set.
xV 1Z&l
*/ 3_eml\CY
publicvoid setPage(Page page){ ?o(X0
this.page = page; b\Xu1>
} +_XbHjhN/
*ZSp9g"Z
/** u+tb83~[=
* @param users :_YG/0%I
* The users to set. a$ ! {Tob2
*/ % x*Ec[l
publicvoid setUsers(List users){ 3ws(uF9$
this.users = users; Iv|WeSL.
} "KI,3g _V
53+rpU_
/** d_7Xlp@
* @param userService VU0tyj$
* The userService to set. .]ZuG
*/ acju!,G
publicvoid setUserService(UserService userService){ =UKR<@QrK
this.userService = userService; .gkPG'm[
} AoOG[to7
} SnF[mN'
dV=5_wXZ$
6 r-n6#=
3w:Z4]J
[.Wt,zrE
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, .fh?=B[o#
M^JZ]W(
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 $\@ V4
,t&-`U]AX
么只需要: ~md|k
java代码: [dF=1E>W_J
w{O3P"N2
]3y5b9DuW
<?xml version="1.0"?> |tJ%:`DGw
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork #`L}.
&eS70hq
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 6'*Uo:]
/uz5V/i0
1.0.dtd"> ?N?pe}
pr,1Wp0l
<xwork> %iS]+Sa.K
(*WZsfk>/<
<package name="user" extends="webwork- wukos5
NlEWm8u
interceptors"> _5S$mc8K0
JTB~nd>
<!-- The default interceptor stack name +e4<z%1
CU`Oc>;*T
--> g!Yh=kA'N
<default-interceptor-ref pfQZ|*>lkb
*|#JFy?c[
name="myDefaultWebStack"/> l}-`E@w
/Vd#q)b%T
<action name="listUser" 1Da [!^u,D
3a)Q:#okD
class="com.adt.action.user.ListUser"> /FV6lR!0^
<param 0#{]!>R
"XsY~
name="page.everyPage">10</param> 1@z@
<result ow$l!8
;AB ,:*
name="success">/user/user_list.jsp</result> O*/-I
pM
</action> GJt9hDM$0
3N*C]
</package> 8lGgp&ey
(Dh;=xG
</xwork> S!!\!w>N
2/4x]i
H*
ts\>_/
S,9WMti4x
@=#s~ 3
Z*aU2Kr`;
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 `"":
St&H