Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 yWI30hW
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 r{y&}gA
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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 }Ruj h4*
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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 r!H'8O!
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分页支持类: 7!%/vO0m
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java代码: Dep.Qfv{-
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package com.javaeye.common.util; hY$gzls4
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import java.util.List; ;Du+C%
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publicclass PaginationSupport { T(LqR?xOo
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publicfinalstaticint PAGESIZE = 30; ^PwZP;On
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privateint pageSize = PAGESIZE; @qP
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privateList items; P2y`d9,Q
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privateint totalCount; DK' ? '
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privateint[] indexes = newint[0]; |wF_CZ*1
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privateint startIndex = 0; P2HR4`c
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public PaginationSupport(List items, int 9a\H+Y~
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totalCount){ Swugt"`nN
setPageSize(PAGESIZE); r6
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setTotalCount(totalCount); m]C|8b7Y
setItems(items); OIi8x?
.~]
setStartIndex(0); 6T-h("t
} X`/3X}<$7
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public PaginationSupport(List items, int R _#x
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totalCount, int startIndex){ MW^(
setPageSize(PAGESIZE); 3y&N}'R(F
setTotalCount(totalCount); M%(B6};J
setItems(items); 'p%aHK{
setStartIndex(startIndex); rGa@!^hk
} Ck`-<)uN
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public PaginationSupport(List items, int g.L~Z1-
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totalCount, int pageSize, int startIndex){ @zu IR0Gr)
setPageSize(pageSize); 54[#&T$S
setTotalCount(totalCount); z1dSZ0NoA
setItems(items); e}@VR<h
setStartIndex(startIndex); pe}mA}9U
} #&v86
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publicList getItems(){ GvAP
return items; U}#3LFr.?
} Zv[D{
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publicvoid setItems(List items){ 7rIz
this.items = items; 7j,-o
} qq
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publicint getPageSize(){ 5OHg% ^
return pageSize; =sm<B^yj
} X`/GiYTu
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publicvoid setPageSize(int pageSize){ dh9Qo4-{
this.pageSize = pageSize; VtP^fM^{
} _v/w
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publicint getTotalCount(){ !sknO53`H`
return totalCount; D.[h`Hkc
} s<z`<^hRe
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publicvoid setTotalCount(int totalCount){ 3o_)x
if(totalCount > 0){ _\/KI
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this.totalCount = totalCount; mS$9D{
int count = totalCount / [zC1LTXe
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pageSize; )2z<5 `
if(totalCount % pageSize > 0) &7\=Jw7w
count++; _h6j, )
indexes = newint[count]; Q,ezAE
for(int i = 0; i < count; i++){ ^`~s#L7
indexes = pageSize * $&25hvK,
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i; uBp,_V?
} <mrvuWg0
}else{ LoUHStt
this.totalCount = 0; W)X" G3
} #!0=I
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} N>TmaUk
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publicint[] getIndexes(){ xNrPj8V<Y
return indexes; /M :7
} jj,CBNo(
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publicvoid setIndexes(int[] indexes){ bUzo> fm_
this.indexes = indexes; ,59G6o
} tG7F!um(
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publicint getStartIndex(){ (HEi;
return startIndex; 3 as~yF0
} u1}/SlCp
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publicvoid setStartIndex(int startIndex){
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if(totalCount <= 0) %K`th&331
this.startIndex = 0; bIWSNNV0F
elseif(startIndex >= totalCount) JpRn)e'Z
this.startIndex = indexes 4Wd
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[indexes.length - 1]; Ao )\/AR'
elseif(startIndex < 0) ybC0Ee@
this.startIndex = 0; aZ,j1j0p
else{ -lY,lC>{
this.startIndex = indexes m
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[startIndex / pageSize]; %jE0Z4\
} 4-CGe
} sck.2-f"
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publicint getNextIndex(){ .9u0WP95
int nextIndex = getStartIndex() + 2M+}o"g
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pageSize; /n2qW.qJ>
if(nextIndex >= totalCount) n2(`O^yd7C
return getStartIndex(); [59g] ')
else j%U'mGx
return nextIndex; ynZp|'b?<
} 1!%T<!A.
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publicint getPreviousIndex(){ Yu}[RXC(=
int previousIndex = getStartIndex() - +=`*`eP:U
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pageSize; pJ3-f k"i
if(previousIndex < 0) zH13~\
return0; 6Y%{ YQ}s|
else ^, &'
return previousIndex; /HE{8b7n3F
} ~eZ]LW])
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} {/|tVc63
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抽象业务类 ,rNv}
java代码: .MS41
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/** Rb_%vOM
* Created on 2005-7-12 FvJkb!5*e_
*/ cCuK?3V4K
package com.javaeye.common.business; rw$ =!iyO
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import java.io.Serializable; NY
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import java.util.List; m;JB=MZ=m
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import org.hibernate.Criteria; @iU(4eX
import org.hibernate.HibernateException; ^H!45ph?Jc
import org.hibernate.Session; G+1i~&uV
import org.hibernate.criterion.DetachedCriteria; kXgc'w6EhF
import org.hibernate.criterion.Projections; arc{:u.K
import w.(?O;
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org.springframework.orm.hibernate3.HibernateCallback; >|pN4FS
import a0jzt!ci
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org.springframework.orm.hibernate3.support.HibernateDaoS Gn %"B6
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upport; O'{g{
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import com.javaeye.common.util.PaginationSupport; YmwXA e:
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public abstract class AbstractManager extends 4 'DEdx,&f
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HibernateDaoSupport { 48,uO!
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privateboolean cacheQueries = false; /?1^&a
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privateString queryCacheRegion; U/A
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publicvoid setCacheQueries(boolean @e-2]z
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cacheQueries){ iHT=ROL
this.cacheQueries = cacheQueries; q $=[v
} C{>dE:*K^
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publicvoid setQueryCacheRegion(String iEx4va-j
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queryCacheRegion){ **.g^Pyc
this.queryCacheRegion = AHU=`z
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queryCacheRegion; *LEI@
} } "&Ye
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publicvoid save(finalObject entity){ M0t9`Z9
getHibernateTemplate().save(entity); #fDM{f0]R
} B%WkM\\!^
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publicvoid persist(finalObject entity){ ; Kh!OBZFo
getHibernateTemplate().save(entity); nwVW'M]r
} c=D~hz N
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publicvoid update(finalObject entity){ @V Sr'?7-
getHibernateTemplate().update(entity); :_h#A}8Xd
} Ek60[a
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publicvoid delete(finalObject entity){ 4+Jf!ovS=
getHibernateTemplate().delete(entity); mRy0zN>?
} ,hWuAu6.L
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publicObject load(finalClass entity, dwouw*8
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finalSerializable id){ :m<#\!?
return getHibernateTemplate().load |_hIl(6F5N
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(entity, id); kz G W/
} `i!fg\qnK
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publicObject get(finalClass entity, V@nZ_.
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finalSerializable id){ }^
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return getHibernateTemplate().get >[ g=G
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(entity, id); qYQ
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} z 'V$)U$f
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publicList findAll(finalClass entity){ pwRCfR)" X
return getHibernateTemplate().find("from +i[vJRLxl~
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" + entity.getName()); k~?5mUyK<
} dU2:H}
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publicList findByNamedQuery(finalString 7~SnY\B|
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namedQuery){ et/v/Hvw1
return getHibernateTemplate 8~F?%!X
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().findByNamedQuery(namedQuery); x.sC015Id
} oPVt
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publicList findByNamedQuery(finalString query, '>HLE) l
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finalObject parameter){ }qR6=J+Dx
return getHibernateTemplate #|T2`uYotf
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().findByNamedQuery(query, parameter); xUTTRJ(\
} cdN =HM~I
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publicList findByNamedQuery(finalString query, dK4w$~j{k
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finalObject[] parameters){ Ir=G\/A
return getHibernateTemplate +.g j/uy*
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().findByNamedQuery(query, parameters); VB`% u=
} fYW9Zbov-
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publicList find(finalString query){ =G !]_d0
return getHibernateTemplate().find yq1G6hw
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(query); M@Ti$=
} v57<b&p26
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publicList find(finalString query, finalObject Qkw?QV-`k
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parameter){ R\<d&+q@
return getHibernateTemplate().find XM#nb$gl
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(query, parameter); T=RabKVYP
} qFl|q0\ A
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public PaginationSupport findPageByCriteria E^0a; |B[
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(final DetachedCriteria detachedCriteria){ TM|PwY
return findPageByCriteria ?<S fhjU
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); R7KV
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} 4aW[`
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public PaginationSupport findPageByCriteria yE~D0%Umq
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(final DetachedCriteria detachedCriteria, finalint ~=I:go
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startIndex){ a!f71k
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return findPageByCriteria %xKZ"#Z#K
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(detachedCriteria, PaginationSupport.PAGESIZE, R&$fWV;'
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startIndex); !R@jbM
} ,9MNB3
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public PaginationSupport findPageByCriteria 5"(FilM
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(final DetachedCriteria detachedCriteria, finalint CNhLp#
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pageSize, dk"@2%xJ2d
finalint startIndex){ 7-C])9
return(PaginationSupport) NNwGRoDco
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getHibernateTemplate().execute(new HibernateCallback(){ j WMTQLE.
publicObject doInHibernate *Vg) E*s
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(Session session)throws HibernateException { "rfBYl`
Criteria criteria = <;uM/vSi
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detachedCriteria.getExecutableCriteria(session); A-J#$B
int totalCount = OJh MM-
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((Integer) criteria.setProjection(Projections.rowCount
}Oqt=Wm
kB%.i%9\\
()).uniqueResult()).intValue(); }8s&~fH
criteria.setProjection _g-0"a{-
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(null); gVy`||z
List items = 4#:C t* f
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criteria.setFirstResult(startIndex).setMaxResults owI:Qs_/4
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(pageSize).list(); z@ `u$D$n
PaginationSupport ps = hm
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new PaginationSupport(items, totalCount, pageSize, Rf2mBjJ(z
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startIndex); C7f*Q[
return ps; %|1s9?h7\
} id" l"
}, true); ?YUL~P
} VDZOJM)(
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public List findAllByCriteria(final Z[B:6\oQ
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DetachedCriteria detachedCriteria){ l2YA/9.
return(List) getHibernateTemplate ,?HM5c{'[Y
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().execute(new HibernateCallback(){ |.$7.8g
publicObject doInHibernate MOay^{u
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(Session session)throws HibernateException { C\vOxBAB
Criteria criteria = ,yvS c
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detachedCriteria.getExecutableCriteria(session); d0&
return criteria.list(); mahNQ5 W*)
} =+I-9=
}, true); <M}O&?N
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} g/\cN(X
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public int getCountByCriteria(final q*C-DiV
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DetachedCriteria detachedCriteria){ 8R-;cBT
Integer count = (Integer) 5uOz #hN
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getHibernateTemplate().execute(new HibernateCallback(){ shP}T[<
publicObject doInHibernate F2ISg'
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(Session session)throws HibernateException { ;>;it5 l=
Criteria criteria = 2-Wy@\
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detachedCriteria.getExecutableCriteria(session); o^MoU2c
return 3 TTQff
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criteria.setProjection(Projections.rowCount wXKt)3dm u
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()).uniqueResult(); '#eT
} {E7STLQ_%
}, true); H
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return count.intValue(); ,A)Z.OWOq
} /L5:/Z
} q_mxZM
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用户在web层构造查询条件detachedCriteria,和可选的 8G9( )UF.
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 B7YE+
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PaginationSupport的实例ps。 065 =I+Vo
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ps.getItems()得到已分页好的结果集 zA:q/i
ps.getIndexes()得到分页索引的数组 jUgx
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ps.getTotalCount()得到总结果数 A wk1d
ps.getStartIndex()当前分页索引 ;sq xFF@
ps.getNextIndex()下一页索引 zK{}
ps.getPreviousIndex()上一页索引 6Z2|j~
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Uj3HAu
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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 wzJdS}Yy!y
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一下代码重构了。 pG"hZB3)
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我把原本我的做法也提供出来供大家讨论吧: J#t8xL
Z,81L3#6
首先,为了实现分页查询,我封装了一个Page类: :XPat93w
java代码: \pTv;(
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/*Created on 2005-4-14*/ [?;L
package org.flyware.util.page; YnW9uy5
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/** <F"G~.^ *s
* @author Joa ?4Fev_5m
* 5p5"3m;M7
*/ apgKC;
publicclass Page { -1`}|t;
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/** imply if the page has previous page */ *M0O&" ~j
privateboolean hasPrePage; `P-d. M6Oa
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/** imply if the page has next page */ C dPQhv)m
privateboolean hasNextPage; D%c^j9' 1
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/** the number of every page */ Wa.!eAe}
privateint everyPage; E|SmvIV-
%g3QE:(2@q
/** the total page number */ ]KXyi;n2
privateint totalPage; NYs<`6P:Y
o{n#f?EA
/** the number of current page */ ~ _tK.m3
privateint currentPage; }J92TV
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/** the begin index of the records by the current 7!FiPH~kM
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query */ a2i:fz=[
privateint beginIndex; jsr)
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/** The default constructor */ h4MBw=Tz~
public Page(){ 0Js5 '
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} &jQqlQ j
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/** construct the page by everyPage <S6?L[_
* @param everyPage '&K' 0qG
* */
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public Page(int everyPage){ E?|NYu#I6
this.everyPage = everyPage; X%fLV(
} S1'?"zAmd
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/** The whole constructor */ _v,Wl/YAp
public Page(boolean hasPrePage, boolean hasNextPage, T
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int everyPage, int totalPage, sCQV-%9
int currentPage, int beginIndex){ ^T1caVb|>
this.hasPrePage = hasPrePage; Us2> 5 :\
this.hasNextPage = hasNextPage; $#W^JWN1
this.everyPage = everyPage; t7xJ"
this.totalPage = totalPage; /d Ua
this.currentPage = currentPage; ) .' + {
this.beginIndex = beginIndex; *8yC6|wL?
} qD=b+\F
M
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/** B,Tv9(sv
* @return *-q&~
* Returns the beginIndex. ]W~M?1}
*/ v4uQ0~k~X
publicint getBeginIndex(){ H!6&'=c {k
return beginIndex; tI#65ox#
} 2bw.mp&v1
;'Z"CbS+
/** o54=^@>O<j
* @param beginIndex xcQ^y}JN
* The beginIndex to set. D(dV{^} 9
*/ oY,{9H37b
publicvoid setBeginIndex(int beginIndex){ :J2^Y4l2
this.beginIndex = beginIndex; f><V;D#
} v@s"*E/PF7
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/** Jcs
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* @return vQn hb%
* Returns the currentPage. %]tW2s"
*/ k*F9&-rtN
publicint getCurrentPage(){ iS"6)#a72
return currentPage; I|c?*~7*
} 0QrRG$<4X
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/** AxTFVot
* @param currentPage o:
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* The currentPage to set. bu\(KR$s
*/ EqIs&){
publicvoid setCurrentPage(int currentPage){ O~x{p,s
U
this.currentPage = currentPage; ;<E?NBV^
} ]rg-=Y k
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/** n: {f\
* @return <4 /q5*&
* Returns the everyPage. |q\i, }
*/ F*Yx1vj
publicint getEveryPage(){ s+G(N$0U
return everyPage; dpt P(H
} ZGCp[2$
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/** /;21?o
* @param everyPage &f?JtpB
* The everyPage to set. NxK.q)tj6
*/ HAs/f#zAk6
publicvoid setEveryPage(int everyPage){ 1L\r:mx3
this.everyPage = everyPage; |N
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} q$}J/w(,
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/** Ip8:~Fl]
* @return @j%@Z
* Returns the hasNextPage. q1r-xsjV=
*/ _)3C_G1!
publicboolean getHasNextPage(){ fJ\u8
return hasNextPage; q%/.+g2-\
} ('d,Sh
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/** Cgf4E{\U!
* @param hasNextPage R /_vJHI
* The hasNextPage to set. $!z .[GL
*/ P(C5@x(Z
publicvoid setHasNextPage(boolean hasNextPage){ Tpkt'|8
this.hasNextPage = hasNextPage; )2Y]A^ Y
} @KZW*-"
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u
/** 07ppq?,y
* @return 7nW <kA
* Returns the hasPrePage. ^d(gC%+!u
*/ .O+,1&D5
publicboolean getHasPrePage(){ g0;6}n
return hasPrePage; UKB/>:R
} +9<:z\B|
X .K*</(g
/** |B^Picu
* @param hasPrePage ke/4l?zs
* The hasPrePage to set. eU]I !pI<
*/ F)/4#[
publicvoid setHasPrePage(boolean hasPrePage){ N1vA>(2A
this.hasPrePage = hasPrePage; ^EmePkPI
} iT{[zLz>1
I;, n|o
/** 8S[bt@v
* @return Returns the totalPage. u`!Dp$P
* ~=otdJ
*/ 8e`HXU(A
publicint getTotalPage(){ FZ8Qj8
return totalPage; F6h IG G
} [w+1<ou;j
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/** UCTc$3
* @param totalPage 1$m{)Io2(
* The totalPage to set. 2)
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*/ c<Q*g
publicvoid setTotalPage(int totalPage){ 7c@5tCcC-
this.totalPage = totalPage; :kjs: 6f]
} <l+hcYam
cVmF'g
} I0^oaccM
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*r!qxiY=
r
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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 aan(69=jz
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个PageUtil,负责对Page对象进行构造: 5,Co(K
java代码: jz\>VYi(7
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/*Created on 2005-4-14*/ 'S=eW_ 0/
package org.flyware.util.page; 6&2{V?
W3
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import org.apache.commons.logging.Log; ]/[@.
import org.apache.commons.logging.LogFactory; /}CAd
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/** kmu7~&75
* @author Joa .n?i'8
* D@@"w+
*/ J10&iCr{r*
publicclass PageUtil { iqsR]mab
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privatestaticfinal Log logger = LogFactory.getLog nwDGzC~y<
$)=`Iai
(PageUtil.class); AD6 b
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/** jHx\YK@e\
* Use the origin page to create a new page lg^Lk\Y+re
* @param page _skE\7&>X
* @param totalRecords 7Q&S [])
* @return 3B$|B,
*/ v.g Ai6
publicstatic Page createPage(Page page, int :e}j$vF
7sVO?:bj}
totalRecords){ +.m:-^9
return createPage(page.getEveryPage(), DKl\N~{F
y'^b{q@
page.getCurrentPage(), totalRecords); /<o?T{z<-
} FJW,G20L
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/** T~?&hZ>
* the basic page utils not including exception m*KI'~#$%
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handler %F:; A
* @param everyPage g12.4+
* @param currentPage T[J8zLO
* @param totalRecords "VMb1Zhf
* @return page b.)jJLWv@
*/ :n?rk/ F
publicstatic Page createPage(int everyPage, int b~TTz`HZ
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currentPage, int totalRecords){ ~cfvL*~5
everyPage = getEveryPage(everyPage); \GGyz{i
currentPage = getCurrentPage(currentPage); W!* P
int beginIndex = getBeginIndex(everyPage, ;9vY5CxzC
#aKUD
currentPage); JPg^h
int totalPage = getTotalPage(everyPage, \e%%ik,<
(>*L-&-
totalRecords); [Z!oVSCZD%
boolean hasNextPage = hasNextPage(currentPage, Z)}2bJwA
0}g~69Z1=
totalPage); F-D$Y?m
boolean hasPrePage = hasPrePage(currentPage); RXO5pd
D\pX@Sx,v[
returnnew Page(hasPrePage, hasNextPage, V7
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everyPage, totalPage, KJt6d`ZN
currentPage, (:}}p}u
X 0LC:0+
beginIndex); q3GkfgY
} J{nA
?[
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privatestaticint getEveryPage(int everyPage){ hE4qs~YB!
return everyPage == 0 ? 10 : everyPage; ^ Qxv5HS2
} )X8N|W>vh
! 'Hd:oD<
privatestaticint getCurrentPage(int currentPage){ =RofC9,
return currentPage == 0 ? 1 : currentPage; mRC
} V2'5doo
hXD/
privatestaticint getBeginIndex(int everyPage, int 6E_YUk?KW
<s'0<e!./t
currentPage){ 65rf=*kz:
return(currentPage - 1) * everyPage; Mh@n>+IR
} LeNSjxB
m'uFj !
privatestaticint getTotalPage(int everyPage, int "@Qg]#]JH
!=6 \70lJ
totalRecords){ @r\{iSg&g.
int totalPage = 0; G"Hj$
:_o^oi7G
if(totalRecords % everyPage == 0) #+|0 o-
totalPage = totalRecords / everyPage; Qp>Z&LvC5
else D|'[ [=
totalPage = totalRecords / everyPage + 1 ; ,z>w^_
1L=)93,M
return totalPage; hOuHTo^
} gE8>o:6)6:
/.sho\a
privatestaticboolean hasPrePage(int currentPage){ isFxo,R9r
return currentPage == 1 ? false : true; X-psao0tI`
} w`gT]Rn
6Q]JY,+
privatestaticboolean hasNextPage(int currentPage, $|AasT5w
-_Kw3x
int totalPage){ 8wn{W_5a
return currentPage == totalPage || totalPage == LbR'nG{J
+/hd;s$x
0 ? false : true; (?"z!dg c
} B_XX)y %V
6wZ)GLW[
=RQI5nHdw
} f5/s+H!
as[! 9tB]
F#.ph?W
'@HCwEuz
*<X*)A{C
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。 |n~,{=
}eveNPB{5
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 >G As&\4hs
9q\_UbF
做法如下: CW]Th-xc
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >qd=lm <,
buhbUmQ2
的信息,和一个结果集List: Q&/WVRD
java代码: i4&V+h"
]<C]&03))
1Afy$It/{
/*Created on 2005-6-13*/ j}6h}E&dEr
package com.adt.bo; V~do6[(
A,3qjd,$ c
import java.util.List; i>dFpJ
jWdZ]0m
import org.flyware.util.page.Page; g2A#BMe'.$
>B;KpO"+m
/** ]kF1~kXBe
* @author Joa + f:!9)C
*/ QXgfjo
publicclass Result { u^W!$OfZpp
^sqzlF
private Page page; M0`1o p1
p8Z;QH*
private List content; #L57d
d qO]2d
/** =r3g:j/>q
* The default constructor
=y`-:j\
*/ 6;;2e> e
public Result(){ s^Xs*T@~h
super(); A8Km8"
} q$Ms7` a
0f_A"K
/** kO$n0y5e
* The constructor using fields ab]Q1kD
* hFxT@I~
* @param page 0|8cSE<
i
* @param content D|^N9lDaQ
*/ [a?bv7Kz
public Result(Page page, List content){ A;o({9VH`Z
this.page = page; Ge^,hAM'
this.content = content; ^66OzT8A
} =YD<q:n4
w^,Xa
/** WZh_z^rwn
* @return Returns the content. y,w_x,m
*/ &>QxL d#
publicList getContent(){ )<qL8#["U
return content; m_,Jbf
} 5u3KL
A
?Mn~XN4F_
/** {dn:1IcN
* @return Returns the page. l}&2A*c.
*/ M0OIcMTv
public Page getPage(){ k4E9=y?
return page; ,s2C)bb-
} KVUub'k
$`lm]} {&
/** \,r*-jr
* @param content 0j8`M"6
* The content to set. afzx?ekdF
*/ ?e,:x ]\L
public void setContent(List content){ >y(loMl
this.content = content; 1b 2
} ,+I]\ZeO
%s^1 de
/** G;EJ\J6@Yw
* @param page 23 #JmR
* The page to set. t*H|*L#YR
*/ ^7Z;=]8J
publicvoid setPage(Page page){ %b2Hm9r+
this.page = page; RzzU+r
} :R>RCR2g)
} k8%@PC$
ZX8@/8sv
7AWq3i{
A}&YK,$5ED
.rnT'""i<5
2. 编写业务逻辑接口,并实现它(UserManager, radP%W-U
UBk:B
UserManagerImpl) c;06>1=wP5
java代码: {J,4g:4G
t1yOAbI
)VqPaKZl
/*Created on 2005-7-15*/ E'5KJn;_7
package com.adt.service; S\Le;,5Z
l-S0Gn/'X
import net.sf.hibernate.HibernateException; ~*<`PD O?
9Oo`4
import org.flyware.util.page.Page; GlRjbNW?Q
'cQ,;y
import com.adt.bo.Result; >Gk<a
po,Ue>n/
/** %[M0TE=J
* @author Joa
Gv}Q/v
*/ H)EL0
Kv/
publicinterface UserManager { GIn%yB'
*X ;ch55\
public Result listUser(Page page)throws u0G
tzk
`%"x'B`mM
HibernateException; &K(y%ieIJ
x%HxM~&
} ]<L~f~vU
g j]8/~lr
5\w*W6y
<W) F{N?
78~/1-
java代码: m^3j|'mG
Aq$1#1J
,^Q~w
b!{
/*Created on 2005-7-15*/ *'aouS/?<6
package com.adt.service.impl; dU2;
!`1m.
import java.util.List; O:pg+o&
|v5
ge3-
import net.sf.hibernate.HibernateException; u86PTp+
NGkxg:
import org.flyware.util.page.Page; Z
P6p>?DQ
import org.flyware.util.page.PageUtil; >goHQ30:
(E&M[hH+
import com.adt.bo.Result; ZbjUOlE02
import com.adt.dao.UserDAO; D
.LR-Z
import com.adt.exception.ObjectNotFoundException; /!A"[Tyt
import com.adt.service.UserManager; 4[MTEBx
kv, !"<
/** M_.Jmh<&&
* @author Joa "5O>egt
*/ CR%h$+dzy
publicclass UserManagerImpl implements UserManager { $Bl51VjN
UnYb}rF#%
private UserDAO userDAO; O>a1S*mxP
ccPWfy_
/** jm@M"b'{
* @param userDAO The userDAO to set. aR('u:@jHi
*/ -)3+/4Q(
publicvoid setUserDAO(UserDAO userDAO){
bZ OCj1
this.userDAO = userDAO; -1d*zySL
} o?t H[
)b>misb/
/* (non-Javadoc) F4WX$;1
* @see com.adt.service.UserManager#listUser V45adDiZ
@G=7A;-pv0
(org.flyware.util.page.Page) kR^h@@'F"
*/ )T^wc:
public Result listUser(Page page)throws [rK`BnJX
JX[]u<h?
HibernateException, ObjectNotFoundException { (xVx|:R[<H
int totalRecords = userDAO.getUserCount(); <eS/-W%n6
if(totalRecords == 0) wVnmT94
throw new ObjectNotFoundException T]tu#h{
a
w?^[*_Y
("userNotExist"); (w5cp!qW9J
page = PageUtil.createPage(page, totalRecords); %N&W_.F6
List users = userDAO.getUserByPage(page); ?wCX:?g
returnnew Result(page, users); F ]Zg
} yRl
6
R})KIG
} U` HY
eJ
|9IOZ>H9
3&AJN#c
Ba|}$jo
q*`
m%3{
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 qQG? k~r
,+6u6
询,接下来编写UserDAO的代码: ruB D
^-
3. UserDAO 和 UserDAOImpl: g<M!]0OK
java代码: C58o="L3S
j>:N0:
nGYimRYO
/*Created on 2005-7-15*/ TNA7(<"fV|
package com.adt.dao; qm:C1#<p
lqJ92vi6Q
import java.util.List; yt5<J-m
eI2HTFyT
import org.flyware.util.page.Page; 9X;*GC;d
PsXCpyY!s
import net.sf.hibernate.HibernateException; FdzdoMY
'ROz| iJ
/** ?Z?(ky!
* @author Joa SlR//h
*/ ZAN~TG<n
publicinterface UserDAO extends BaseDAO { >(.|oT\Tb
=#y;J(>~|
publicList getUserByName(String name)throws PQSmBTs.
KA?%1s(kJ
HibernateException; EK"/4t{L_
OW\vbWX
publicint getUserCount()throws HibernateException; 87+fd_G
R#;xBBt8
publicList getUserByPage(Page page)throws (B\
UZb
~h
Dp-R;
HibernateException; aEIz,^3
S\:+5}
} 1 Ga3[g
R5^6Kwu
E&y)`>Nq{
Xy=ETV%
3x+=7Mg9
java代码:
J9*;Bqzim
7_l
Wr
uyB 2
/*Created on 2005-7-15*/ `NgQ>KV!
package com.adt.dao.impl; _LC*_LT_
v G\J8s
import java.util.List; 37a1O>A
z+6PVQ
import org.flyware.util.page.Page; A-=hvJ5T
GF%/q :9
import net.sf.hibernate.HibernateException; !ae?EJm"
import net.sf.hibernate.Query; tJ >>cFx
f)z(9JJL
import com.adt.dao.UserDAO; `:V'E>B
:dULsl$Nz
/** 6?<lS.s
* @author Joa Y!_c/ !Tx
*/ $9Bzq_!
public class UserDAOImpl extends BaseDAOHibernateImpl i({\fb|0
!'F1Ht
implements UserDAO { YF-E1`+?<
sfn^R+x4,9
/* (non-Javadoc) \ Voly
* @see com.adt.dao.UserDAO#getUserByName 0q-lyVZ^X
7>O`UT<t4@
(java.lang.String) 8uLS7\,$z
*/ o)@nnqa
publicList getUserByName(String name)throws $[fq Th
8_HBcZWs
HibernateException { Nr2,m"R{
String querySentence = "FROM user in class F9K0
(P-^ PNz&
com.adt.po.User WHERE user.name=:name"; 'hBnV xd&
Query query = getSession().createQuery tR'RB@kJ
M`'DD-Q
(querySentence); 8Z9>h:c1
query.setParameter("name", name); 'ZMh<M[
return query.list(); f7Nmvla[q
} _%D7D~2r|
e8xq`:4Y
/* (non-Javadoc) <%uEWb)
* @see com.adt.dao.UserDAO#getUserCount() ?VE'!DW
*/ l_:P|
publicint getUserCount()throws HibernateException { AkS16A
int count = 0; b:Zh|-
String querySentence = "SELECT count(*) FROM c]#}#RJ`\
*.>@
user in class com.adt.po.User"; W&
0R/y7
Query query = getSession().createQuery +O 7(
>a
;#v3C;
(querySentence); >\?
z,Nin
count = ((Integer)query.iterate().next ZJ)Z
zqNzWX
()).intValue(); b,~pwbHf
return count; ^t
gjs$M|
} -`\rDPGf
E#rQJ
/* (non-Javadoc) vMou`[\WlJ
* @see com.adt.dao.UserDAO#getUserByPage ,s3|
6&SNFOX{@
(org.flyware.util.page.Page) ANw1P{9*
*/ Q2m[XcnX
publicList getUserByPage(Page page)throws m6BUKX\m
Ii[U%
HibernateException { ;u'VR}4ph
String querySentence = "FROM user in class ^\O*e)#*
Y"8@\73(R
com.adt.po.User"; mm:TR?^
Query query = getSession().createQuery )Wq1af
^il$t]X5-
(querySentence); T2w4D!
query.setFirstResult(page.getBeginIndex()) ZOV,yuD{8{
.setMaxResults(page.getEveryPage()); zi6J|u
return query.list(); 6z U
} wQy~5+LE
,%IP27bPW
} dR\yRC]I
g{}<ptx]
8el6z2
E<3xv;v8r
`0]N#G
T
至此,一个完整的分页程序完成。前台的只需要调用 GZrN,M
' abEY
userManager.listUser(page)即可得到一个Page对象和结果集对象 }?mSMqnB
mq4Zy3H
的综合体,而传入的参数page对象则可以由前台传入,如果用 "M
iJM+,
t`Z3*?UqI
webwork,甚至可以直接在配置文件中指定。 xJ/)*?@+
TM#L.xPMf
下面给出一个webwork调用示例: aanS^t0
java代码: oz=ULPZ%
O8\f]!O(
B(s^(__]
/*Created on 2005-6-17*/ 8TB|Y
package com.adt.action.user; m"Mj3Z:
r4iNX+h?V
import java.util.List; V||b%Cb1g
Ss5@ n
import org.apache.commons.logging.Log; =
>TU
import org.apache.commons.logging.LogFactory; \ [[xyd
import org.flyware.util.page.Page; ZJ2
MbV.6
tb~E.Lm\
import com.adt.bo.Result; m\jjj^f a
import com.adt.service.UserService; M1m]1<
import com.opensymphony.xwork.Action; )HE{`yiLL
TX$dxHSPK
/** lJFy(^KQG,
* @author Joa w>X@
,
*/ t6+W
publicclass ListUser implementsAction{ y]@JkF(
I(R%j]LX&
privatestaticfinal Log logger = LogFactory.getLog sNpA!!\PM
6}R*7iMs
(ListUser.class); Qm3F=*)d
B6IKD
private UserService userService; nm<VcCc
AzJ;EtR
private Page page; o[Qb/ 7
GP4!t~"1
privateList users; \f4rA?+f
4bL *7bA
/* *\'t$se+
* (non-Javadoc) uQ_C<ii"W
* s&VsK#
* @see com.opensymphony.xwork.Action#execute() 7/hn%obC
*/ YL|)`m0-^5
publicString execute()throwsException{ 084Us
s
Result result = userService.listUser(page); T<Xw[PEnP
page = result.getPage(); Yu" Q
users = result.getContent(); oCkG
return SUCCESS; ].J;8}
} Am@Ta "2
!`Kg&t [&V
/** tc`3-goX
* @return Returns the page. "TaLvworb4
*/ *8,W$pe3
public Page getPage(){ B`R@%US
return page; 9kWI2cLzQt
} %+Nng<_U\T
D
ON.)F
/** O0'|\:my
* @return Returns the users. O6?{@l
*/ y{3+Un
publicList getUsers(){ R3og]=uFzm
return users; AC
<2.i_
} U{ 0~&
a_S`$(7k
/** &Cj~D$kDEu
* @param page P,m+^,
* The page to set. 5L2j,]
*/ o>(<:^x9
publicvoid setPage(Page page){ .^=I&X/P
this.page = page; K:<Viz
} =TEe:%mN
:35h0;8+
/** @a]cI
* @param users 3t+{~{Dj
* The users to set. 9Cd/SlNV2
*/ BQWgL
publicvoid setUsers(List users){ KxKZC}4m
this.users = users; c3l(,5DtH
} T5}3Y3G,6
E)m \KSwh
/** xV+\R/)x
* @param userService ?K pDEH~\
* The userService to set. u{=h%d/
*/ +Eb-|dM
publicvoid setUserService(UserService userService){ V2?{ebx`
this.userService = userService; yc]_ ?S>9
} "4WnDd5"
} +pT;;
9
_J\zj
U3B&3K} ~
"zNS6I?rzE
qh6b;ae\x
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, r1IvA^X
@BnK C&{
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 NVkYm+J#
6<\dQ+~
么只需要: rMJ@oc
java代码: |Tmug X7
J&h59dm-
Xlug{ Uh
<?xml version="1.0"?> 'qiAmaX
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork mz1m^p)~{
AaB1H7r-
1.0//EN" "http://www.opensymphony.com/xwork/xwork- $H3C/|
DI;LhS*z
1.0.dtd"> <?KgzIq2
cu5}(
<xwork> mB0`>?#i
R&t2
<package name="user" extends="webwork- <75x@!
uy"i3xD6-
interceptors"> 9:RV5Dt
-tWxBGSa@
<!-- The default interceptor stack name |b='DJz2
bt1bTo
--> L=Aj+
<default-interceptor-ref r*mYtS
4IW90"uc
name="myDefaultWebStack"/> 7lF;(l^Z>}
l<=k#d
<action name="listUser" N4VZl[7?
X(d:!-_m *
class="com.adt.action.user.ListUser"> emJZ+:%
<param "dndhoMq
!X"nN9k
name="page.everyPage">10</param> aDz%
%%:r
<result +ah4 K(+3
-ys/I,}<
name="success">/user/user_list.jsp</result> #gWok'ZcR
</action> rLD1Cpeb,w
@~$=96^
</package> KMb'm+
$Nvox<d0
</xwork> )2W7>PY
-u~:Gd*l0
?S=y>b9R
dmkGIg}
|uFb(kL[U
"S{GjOlEDF
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 8TH;6-RT
dQH8s
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 {7IZN< e
{be|G^.c
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 TGG=9a]m
mg70%=qM0f
A9Ea}v9:
|iSwG=&
2XBHo (
我写的一个用于分页的类,用了泛型了,hoho + rN#
\C;Yn6PK0
java代码: L*Ffic
>W/mRv&
z/5TYv)S
package com.intokr.util; *pS3xit~
%y>*9$<pXe
import java.util.List; 'dQGb-<_<
$i8oLSRV
/** It 3@
Cd>
* 用于分页的类<br> mDwuJf8}
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 8EiS\$O-
* P%[{ 'u
* @version 0.01 VWXyN
* @author cheng gQhYM7NP{5
*/ C)qG<PW.!
public class Paginator<E> { 60|m3|0o
privateint count = 0; // 总记录数 ^N ;TCn
privateint p = 1; // 页编号 GmUm?A@B
privateint num = 20; // 每页的记录数 kp?_ir
privateList<E> results = null; // 结果 o"N\l{ #s
Ek06=2i
/** +m}D.u*cp
* 结果总数 I)3LJK
*/ Rdj3dg'<
publicint getCount(){ J+Y?'"r
return count; Bq4@I_b
} #cD$
DA
)cOBP}j+
publicvoid setCount(int count){ ]U4C2}u
this.count = count; Ttb ?x<)+8
} -DZ5nx
j~Ci*'*L
/** E7SmiD@)
* 本结果所在的页码,从1开始 n*AN/LBp
* N-p||u
* @return Returns the pageNo. 6I]{cm
*/ Ho%%voJBS
publicint getP(){ @O6
2}F
return p; _!vuDv%
} j6*e^
B
Xe
^NVF
/** h^H)p`[Gme
* if(p<=0) p=1 Kx;l a
* $G/p[JG6-
* @param p 'vZWkeo
*/ =ZV+*cCC=q
publicvoid setP(int p){ @%MGLR{pH
if(p <= 0) ~WmA55
p = 1; se _Oi$VZ{
this.p = p; uqBV KE
} T%PUV \LV
HXB&
6
/** KpQ@cc
* 每页记录数量 {*F8'6YQ$
*/ >#;>6q9_
publicint getNum(){ ` apCu
return num; i|!R*"
} w0.;86<MV
y?*Y=,"
/** '2p,0Bk9i
* if(num<1) num=1 %NhZTmWm
*/ 0)vX
publicvoid setNum(int num){ p@YbIn
if(num < 1) ?O#"x{Pk
num = 1; Jd|E
4h~(
this.num = num; 9PR?'X;4
} '_n$xfH
0e'@Xo2e
/** k <LFH(
* 获得总页数 7X/B9Hee
*/ x)kp*^/
publicint getPageNum(){ YO.+06X
return(count - 1) / num + 1; 99Nm? $g
} `qy@Qo
SQG9m2
/** qHYoQ.ke
* 获得本页的开始编号,为 (p-1)*num+1 oHethk
*/ hus9Zv4
publicint getStart(){ Hq <!&
return(p - 1) * num + 1; \-Q6z8
} NF*Z<$ '%
.Ax]SNZ+:A
/** FCt %of#
* @return Returns the results. EHq?yj;
*/ |s !7U
publicList<E> getResults(){ W_]onq6
return results; [Al}GM
} s%l^zA(
l.SoiFDd
public void setResults(List<E> results){ Kl :x?"g)
this.results = results; SivJaY%
} 0{47TX*YX
w"h3e
public String toString(){ KD..X~Me
StringBuilder buff = new StringBuilder =|3*Y0
T$Rf
(); to] ~$~Q|>
buff.append("{"); }}d,xI
buff.append("count:").append(count); WSx0o}
buff.append(",p:").append(p); { =IAS}
buff.append(",nump:").append(num); E*UE?4FSw|
buff.append(",results:").append ]6?6 k4@
@t#Ju1Y
(results); jH2_Ekgc;_
buff.append("}"); Cl!qdh6
return buff.toString(); CGZ3-OW@E
} z
dUSmb
ff2`4_,|
} R\lUE,o]<q
Z2I2 [pA
G9ra;.