Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 EPfVS
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~0:c{v;4
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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 3_:k12%p
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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 ]>j_
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分页支持类: )`0 j\
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java代码: 1Tkz!
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package com.javaeye.common.util; m\Nc}P_"p
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import java.util.List; g Q^]/X
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publicclass PaginationSupport { b?,y%D)'
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publicfinalstaticint PAGESIZE = 30; C\K--
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privateint pageSize = PAGESIZE; H|?`n
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privateList items; ~{{:-XkVB
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privateint totalCount; 6= D;K.!
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privateint[] indexes = newint[0]; \Ld7fP
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privateint startIndex = 0; 9wzYDKN}
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public PaginationSupport(List items, int =<icHt6s
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totalCount){ stScz#!
setPageSize(PAGESIZE); n9yxZu
setTotalCount(totalCount); =X B)sC%
setItems(items); ce\-oT
setStartIndex(0); I_Qnq4Sk(
} 4)z](e$
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public PaginationSupport(List items, int ?*0kQo'
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totalCount, int startIndex){ 9yPB)&"EF
setPageSize(PAGESIZE); =T`-h"E~@
setTotalCount(totalCount); XhiC'.B_
setItems(items); kzT'
setStartIndex(startIndex); *G4;
} X"sN~Q.0
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public PaginationSupport(List items, int V8/o@I{U[
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totalCount, int pageSize, int startIndex){ bC|~N0b
setPageSize(pageSize); z m%\L/BF
setTotalCount(totalCount); t+tGN\q
setItems(items); uVocl,?.L
setStartIndex(startIndex); y{<7OTA)
} O1"!'Gk[!L
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publicList getItems(){ $qqusa}`K
return items; [%pZM.jFO
}
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publicvoid setItems(List items){ DDEn63{
this.items = items; AKVmUS;70
} {iRNnh
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publicint getPageSize(){ pWqahrWh
return pageSize; SzDi=lY
} *SZ<ori
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publicvoid setPageSize(int pageSize){ w~`P\i@
this.pageSize = pageSize; x0]*'^aA
} 7pNh|#Uv'
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publicint getTotalCount(){ G[mYx[BTz
return totalCount; 6=FuH@Q&
} G(-
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publicvoid setTotalCount(int totalCount){ 0;9LIL5
if(totalCount > 0){ sq%f%?(V
this.totalCount = totalCount; 0IZV4{
int count = totalCount / vzU %5,
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pageSize; NTC,Vr\A
if(totalCount % pageSize > 0) S/4kfsN
count++; !PgYn
indexes = newint[count]; oUqNA|l
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for(int i = 0; i < count; i++){ ;AaF ;zPV
indexes = pageSize * \n5,!,A
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} 3f3?%9
}else{ Y 4U $?%j
this.totalCount = 0; AQ&;y&+QR
} Pz?O_@Ln
} :JlJB
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publicint[] getIndexes(){ a?;{0I:Ln
return indexes; U*Q$:%72vO
} ^%nAx| 4xQ
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publicvoid setIndexes(int[] indexes){ <K43f#%
this.indexes = indexes; ("{'],>
} *(rq AB0~
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publicint getStartIndex(){ )9*WmF c+#
return startIndex; *]LM2J
} NH{0KZ
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publicvoid setStartIndex(int startIndex){ yk=H@`~!
if(totalCount <= 0) /q=<OEC
this.startIndex = 0; 6|zA,-=
elseif(startIndex >= totalCount) 0P|WoCX
this.startIndex = indexes X/Ae-1!
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[indexes.length - 1]; lHx$F?
elseif(startIndex < 0) ]'"$qm:
this.startIndex = 0; I*X|pRD
else{ +2vcUy
this.startIndex = indexes +iXA|L9=
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[startIndex / pageSize]; 4`i_ 4&TS
} 3h4>edM
} 8NLk`/
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publicint getNextIndex(){ :S.0e
int nextIndex = getStartIndex() + L"IdD5`7T
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pageSize; [u<1DR
if(nextIndex >= totalCount) ?xy~N?N
return getStartIndex(); Q@2Smtu~c
else x{=ty*E
return nextIndex; +;vfn>^!b
} /V,:gLpQ
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publicint getPreviousIndex(){ 5[0n'uH
int previousIndex = getStartIndex() - wL:3RZB
8^O|Aa$IF:
pageSize; 4YKb~1qkk
if(previousIndex < 0) YYhRdU/g
return0; GSypdEBj+w
else $Q62
7
return previousIndex; Mq$e5&/
} BsxQW`>^y
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} NbSwn}e_
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抽象业务类 5{{u #W%=
java代码: %KqXtc`O
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/** 4-sUy
* Created on 2005-7-12 t;
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*/ O4 [[9
package com.javaeye.common.business; *vht</?J
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import java.io.Serializable; cBU>/
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import java.util.List; F$d`Umqs;P
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import org.hibernate.Criteria; ?L'ijzP
import org.hibernate.HibernateException; 2nk}'HBe
import org.hibernate.Session; pm^[ve
import org.hibernate.criterion.DetachedCriteria; NKO5c?ds
import org.hibernate.criterion.Projections; d]CRvzW
import pVLfZ?78
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org.springframework.orm.hibernate3.HibernateCallback; XmLHZ,/
import )abo5
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org.springframework.orm.hibernate3.support.HibernateDaoS wF}/7b54
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upport; w_6h
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import com.javaeye.common.util.PaginationSupport; ?k#-)inf)
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public abstract class AbstractManager extends DT;Hr4Z8^"
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HibernateDaoSupport { ._#|h5
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privateboolean cacheQueries = false; Wo\NX05-?
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privateString queryCacheRegion; Jgb{Tl:r
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publicvoid setCacheQueries(boolean VDBP]LRF
8MV=?
cacheQueries){ 'xhX\?mD
this.cacheQueries = cacheQueries; 4k}u`8 a
} S&FMFXF@
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publicvoid setQueryCacheRegion(String @32JMS<
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queryCacheRegion){ qpFFvZ
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this.queryCacheRegion = S'lZ'H /
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queryCacheRegion; q8`JRmt)H
} PO1sVP.S
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publicvoid save(finalObject entity){ 1Sr@$+VGO
getHibernateTemplate().save(entity); LsoP >vJG
} u<:RSg
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publicvoid persist(finalObject entity){ }"E?#&^
getHibernateTemplate().save(entity); !Hxx6/
} P'R!"
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publicvoid update(finalObject entity){ ?FxxH*>"
getHibernateTemplate().update(entity); M5CFW >T
} (ybKACx
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); ?=$a6o
} ,_D`0B6o
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publicObject load(finalClass entity, -$>R;L
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finalSerializable id){ ?l
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return getHibernateTemplate().load p$0G EYwM
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(entity, id); amK"Z<V F
} TkM8GK-3
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publicObject get(finalClass entity, C5c@@ch :
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finalSerializable id){ 4 bw8^
return getHibernateTemplate().get !"Jne'f
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(entity, id); KC[ql}JP
} oYG9i=lZ
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publicList findAll(finalClass entity){ TmxhP
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return getHibernateTemplate().find("from
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" + entity.getName()); 40w,:$
} N7v7b<6
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publicList findByNamedQuery(finalString bH% k)
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namedQuery){ SxI='z_S.f
return getHibernateTemplate -W38#_y/\
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().findByNamedQuery(namedQuery); MqDz cB]
} *<c, x8\s9
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publicList findByNamedQuery(finalString query, 6vAq&Y{JB'
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finalObject parameter){ fkbHfBp[(A
return getHibernateTemplate M_lQ^7/
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().findByNamedQuery(query, parameter); WhQK3hnm
} ^cs:S-s
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publicList findByNamedQuery(finalString query, @ qy
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finalObject[] parameters){ V3r1|{Z(
return getHibernateTemplate lI~T>Lel2
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().findByNamedQuery(query, parameters); jM]B\cvN
} h8B:}_Cu
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publicList find(finalString query){ T#KF@8'-
return getHibernateTemplate().find
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(query); ur7sf$
} ?-C=_eZJ
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publicList find(finalString query, finalObject 1?%Q"*Y&
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parameter){ *'[8FZ|dQ
return getHibernateTemplate().find @-ps[b`z
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(query, parameter); Lu?MRF
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} G%5bQ|O
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public PaginationSupport findPageByCriteria >n3w'b
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(final DetachedCriteria detachedCriteria){ qw?#~"Ca.
return findPageByCriteria u-qwG/$E
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 6bPoC$<Z
} w1U2cbCr/
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public PaginationSupport findPageByCriteria w(Jf;[o
pV:;!+
(final DetachedCriteria detachedCriteria, finalint E/+H~YzO
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startIndex){ y#tuwzE
return findPageByCriteria zNG]v?JAh
', +YWlW
(detachedCriteria, PaginationSupport.PAGESIZE, st4z+$L
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startIndex); 8[v9|r
} y950Q%B]
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public PaginationSupport findPageByCriteria .kwz$b+h
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(final DetachedCriteria detachedCriteria, finalint ={g.Fn(_
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pageSize, f
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finalint startIndex){ z3-A2#c
return(PaginationSupport) j}s<Pn%4
: ;l9to
getHibernateTemplate().execute(new HibernateCallback(){ yBKEw(1
publicObject doInHibernate s|HpN
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(Session session)throws HibernateException { _L8|ZV./
Criteria criteria = "2'4b
=#=<%HPT
detachedCriteria.getExecutableCriteria(session); @kh:o\
int totalCount = &<dC3o!
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((Integer) criteria.setProjection(Projections.rowCount 1F|e/h%^
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()).uniqueResult()).intValue(); LK>AC9ak<
criteria.setProjection ?58,Ja
|; [XZ ZZ
(null); mM#[XKOC<
List items = 6&9}M Oc
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criteria.setFirstResult(startIndex).setMaxResults ;D8175px;
&[yW}uV<7
(pageSize).list(); 7=3'PfS
PaginationSupport ps = zjE|UK{
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new PaginationSupport(items, totalCount, pageSize, S[zETRSG
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startIndex); \|@u)n_
return ps; _s{;9&qX]
} LC>bZ!(i#
}, true); e};\"^HH
} 'v^Zterr
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public List findAllByCriteria(final @"h@4q/W
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DetachedCriteria detachedCriteria){ [[XbKg`"?
return(List) getHibernateTemplate f[ 'uka.U
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().execute(new HibernateCallback(){ pLdZB9oD]C
publicObject doInHibernate 9M12|X\]8
}+@GgipyO.
(Session session)throws HibernateException { kO3N.t@n
Criteria criteria = x&
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detachedCriteria.getExecutableCriteria(session); e0Jz|?d=
return criteria.list(); `*Ju0)g1
} 1Zo"Xb
}, true); [z[<onFIq
} /LK,:6
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public int getCountByCriteria(final D$?}M>
[ !<
DetachedCriteria detachedCriteria){ 9 $&$Fe
Integer count = (Integer) -bP_jIZF;g
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getHibernateTemplate().execute(new HibernateCallback(){ O~*`YsL9
publicObject doInHibernate P->.eo#VG
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(Session session)throws HibernateException { <$>Jsv
Criteria criteria = x=I|O;"><
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detachedCriteria.getExecutableCriteria(session); 5>x?2rp
return ^yFtL(x,
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criteria.setProjection(Projections.rowCount
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()).uniqueResult(); Dg=!d)\
} u*6Y>_iA
}, true); umuE5MKY<
return count.intValue(); c'}dsq\
} al1Nmc#
} NsN =0ff
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用户在web层构造查询条件detachedCriteria,和可选的 @%b&(x^UD
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 N<e72x
@b3jO
PaginationSupport的实例ps。 cii!
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ps.getItems()得到已分页好的结果集 X3zpU7`Av+
ps.getIndexes()得到分页索引的数组 0`Hr(J`F
ps.getTotalCount()得到总结果数 T$IwrTF@?
ps.getStartIndex()当前分页索引 lF#p1H>\
ps.getNextIndex()下一页索引 W[SZZV_(tu
ps.getPreviousIndex()上一页索引 lL;SP&
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}!9KxwC(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 lS96sjJp@
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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 =im7RgIBo
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一下代码重构了。 (N^tg8 Z<
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我把原本我的做法也提供出来供大家讨论吧: (iJ9ekB
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首先,为了实现分页查询,我封装了一个Page类: Vo`,|3^
java代码: 8Cef ]@x
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/*Created on 2005-4-14*/ U9(p ^
package org.flyware.util.page; Hw1:zro
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/** vAcxca">S
* @author Joa |w+N(wcJ
* Q4h6K7
*/ @<ILF69b
publicclass Page { ?F"mZu
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/** imply if the page has previous page */ yFY:D2
privateboolean hasPrePage; ,GUOq!z
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/** imply if the page has next page */ EWC{896,
privateboolean hasNextPage; uA;vW\fHr
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/** the number of every page */ JU3to_Io
privateint everyPage; 73kU\ux
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/** the total page number */ HY2*5#T
privateint totalPage; 7'zXf)!
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/** the number of current page */ ^\Epz*cL
privateint currentPage; e1/{bX5
AU4K$hC^
/** the begin index of the records by the current t.pn07$
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query */ T)o>U&KNP
privateint beginIndex; f)19sjAJk
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/** The default constructor */ +x]3 -s
public Page(){ H;c3 x"
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} TD-o-*mO
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/** construct the page by everyPage svvl`|n%
* @param everyPage M2!2J
* */ i`^[_
public Page(int everyPage){ qV5lv-p
this.everyPage = everyPage; 2bu > j1h
} 0vZ49}mb)
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/** The whole constructor */ 4l'`q+^-
public Page(boolean hasPrePage, boolean hasNextPage, *2>kic
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int everyPage, int totalPage, :5[1Iepdn
int currentPage, int beginIndex){ K_ Od u^
this.hasPrePage = hasPrePage; v3b+Ddp
this.hasNextPage = hasNextPage; DH Qs_8Df
this.everyPage = everyPage; <O0.q.
this.totalPage = totalPage; I=2b)"t0
this.currentPage = currentPage; $pJw
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this.beginIndex = beginIndex; t.Yf8Gy
} (v}4,'dS
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/** _=_<cgy1u
* @return txik{' :
* Returns the beginIndex. *f o>
*/ 7 T
publicint getBeginIndex(){ 722:2 {
return beginIndex; (vFO'jtcB-
} Y/ I32@
k}0b7er=R
/** kRqe&N e
* @param beginIndex Ay0.D FL
* The beginIndex to set. Z(I=KBI
*/ s63!]LDr
publicvoid setBeginIndex(int beginIndex){ [H@71+_Q
this.beginIndex = beginIndex; ~L4L|q 7
} TPVB{
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/** ]
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* @return =2@V}
* Returns the currentPage. tU0jFBB
*/ C}qHvwFm
publicint getCurrentPage(){ mXs.@u/
return currentPage; IU;a$
} \V#fl
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/** |:]}u|O
* @param currentPage m5v IS
* The currentPage to set. =&F~GCZ>
*/ R PdFLC/
publicvoid setCurrentPage(int currentPage){ :%>)S
this.currentPage = currentPage; )4TP{tp
} E[cH/Rm
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/** F:og :[
* @return 01~
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* Returns the everyPage. SuXeUiK.[
*/ ERy=lP~gV
publicint getEveryPage(){ <HnpI
return everyPage; r{KQ3j9O
} IGOEqUw*
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/** =!\Y;rk
* @param everyPage p\R&vof*
* The everyPage to set. !Df>Q5~g
*/ .C` YO2,
publicvoid setEveryPage(int everyPage){ zpjE_|
this.everyPage = everyPage; ]$=#:uf
} (K_{a+$[
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/** c \;_jg
* @return O-huC:zZh
* Returns the hasNextPage. m}7Nu
*/ Sc]G7_
publicboolean getHasNextPage(){ pI_dV44W
return hasNextPage; YmCu\+u
} W{c
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/** k{H7+;_
* @param hasNextPage z'7XGO'Lo
* The hasNextPage to set. ~1{ppc+
*/ E\ls- (,
publicvoid setHasNextPage(boolean hasNextPage){ Y?3f
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this.hasNextPage = hasNextPage; l0U23i
} &$ud;r#
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/** pD('6C;
* @return !hFhw1
* Returns the hasPrePage. 4xH/a1&p=
*/ FA+"t^q
publicboolean getHasPrePage(){ 7]9,J(:Ed
return hasPrePage; c8T| o=`k6
} Nv^byWqu
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/** jtUqrJFlQ
* @param hasPrePage {PR "}x
* The hasPrePage to set. rzs-c ?
*/ )xiu
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publicvoid setHasPrePage(boolean hasPrePage){ }V[ORGzox
this.hasPrePage = hasPrePage; l6L?jiTl_
} PQp =bX,
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/** p{}4#+-<#H
* @return Returns the totalPage. A $ ]s{`
* Q'qX`K+@`
*/ AVm+
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publicint getTotalPage(){ YN+vk}8 <
return totalPage; a{@}vZx>3
} 050,S`%<g8
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/** L^r & .N\
* @param totalPage ;s;3cC!
* The totalPage to set. xW]65iav
*/ xK_oV+
publicvoid setTotalPage(int totalPage){ ^,#my<{
this.totalPage = totalPage; !JyY&D~`
} Svb>s|D
tJ
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} .`Q^8|$-K
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 hf^<lJh~=
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个PageUtil,负责对Page对象进行构造: V$sY3,J7A%
java代码: ZPyzx\6\
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/*Created on 2005-4-14*/ P#,;)HF
package org.flyware.util.page; *yaS^k\
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@8Y
import org.apache.commons.logging.Log; &!OEd]
import org.apache.commons.logging.LogFactory; dFF=-_O>
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/** eZaSV>27
* @author Joa I/%v`[
*
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*/ GB35o uE
publicclass PageUtil { #c5jCy}n
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privatestaticfinal Log logger = LogFactory.getLog Pc_aEBq
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(PageUtil.class); tq}45{FH3
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/** |K"Q>V2y
* Use the origin page to create a new page ZZ7qSyBs?
* @param page 7/
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* @param totalRecords MUAs(M;
* @return ,wwO0,"y7
*/ kQ lU.J>^
publicstatic Page createPage(Page page, int dH!z<~
An$2='=/
totalRecords){ xC,x_:R`
return createPage(page.getEveryPage(), bh<;px-
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page.getCurrentPage(), totalRecords); !t^DN\\#
} e=WjFnK[x7
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/** }Nsdk',}
* the basic page utils not including exception D%abBE1
USEb} M`
handler Jsysk $R
* @param everyPage !R"W2 Z4h
* @param currentPage \gk.[={^P
* @param totalRecords -}9^$}PR
* @return page mAtqF
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*/ EU %,tp
publicstatic Page createPage(int everyPage, int ^>?=L\[
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currentPage, int totalRecords){ %'yrIR
everyPage = getEveryPage(everyPage); <;6{R#Tuh
currentPage = getCurrentPage(currentPage); {]< G=]'
int beginIndex = getBeginIndex(everyPage, 8o$rF7.-
,|{`(y/v
currentPage); /{\ /e"5
int totalPage = getTotalPage(everyPage, I I+y
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totalRecords); ;^5k_\
boolean hasNextPage = hasNextPage(currentPage, yGdX>h
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totalPage); MLu!8dgI
boolean hasPrePage = hasPrePage(currentPage); V0=%$tH
[b:&y(
returnnew Page(hasPrePage, hasNextPage, gvA}s/
everyPage, totalPage, T&?g)
currentPage, NOo?
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beginIndex); q(6.VU@
} n^Ca?|}
,
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privatestaticint getEveryPage(int everyPage){ OT%E|) 6'
return everyPage == 0 ? 10 : everyPage; 94rSB}b.O
} j#1G?MF
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privatestaticint getCurrentPage(int currentPage){ P.'.KZJ:WD
return currentPage == 0 ? 1 : currentPage; u^~7[OkE
} %.Ma_4o
Z
rm8Ys61\=
privatestaticint getBeginIndex(int everyPage, int +;?mg(:
@-'a{hBR
currentPage){ Nmj)TOEPW
return(currentPage - 1) * everyPage; mG jB{Q+
} *M1GVhW(+
:V(LBH0
privatestaticint getTotalPage(int everyPage, int 0O9b
7F
C#kE{Qw10r
totalRecords){ \8 `7E1d
int totalPage = 0; >>y`ap2%V
H<(F$7Q!\
if(totalRecords % everyPage == 0) 68Fl/
totalPage = totalRecords / everyPage; j
uA@"SG
else \c<
oVF'
totalPage = totalRecords / everyPage + 1 ; fF(2bVKP:
;
oyV8P$
return totalPage; |ia5Mr"t
} eV[{c %wN:
;6W ]f([
privatestaticboolean hasPrePage(int currentPage){ &h-_|N
return currentPage == 1 ? false : true; MJ|tfQwhx
} wJy]Vyd
C !j3@EZ$
privatestaticboolean hasNextPage(int currentPage, "do5@$p|
3iCe5VF
int totalPage){ S,c{LTL
return currentPage == totalPage || totalPage == 42NfD/"g+s
L ;L:
0 ? false : true; --K)7
} !l (Vk
T$5wH )<
L4>14D\
} 9>)b6)J D
^kKLi
)9YDNVo*-
ZnEgU}g<2
(Q*q#U
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 OS(`H5D
.z>/A/&+
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 B\J[O5},
j&8YE7
做法如下: 6}^x#9\
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 sL$sj|" S
p&(0e,`z/
的信息,和一个结果集List: -9b=-K.y
java代码: ;_,jy7lf
7Qd4L.
*k{Llq
/*Created on 2005-6-13*/ T
lXS}5^
package com.adt.bo; C4mkt2Eb0a
gP%<<yl
import java.util.List; 3:,%>#"
!> sA.L&=
import org.flyware.util.page.Page; X-\$<DiJGv
9q`Ewj R
/** QVT0.GzR
* @author Joa e>MtDJ5
*/ 2{ F-@}=
publicclass Result { |]&3*%b@
LJeq{Z
private Page page; #{6VdWZ
T|~5dZL
private List content; ~c EN=(Z~r
3H#,qug$
/** La ?A@SD
* The default constructor |
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*/ bpY*;o$~
public Result(){ ] &8em1
super(); 3r~8:F"g
} (JbRhcg
6s@!Yn|?
/** 7ys' [G|}r
* The constructor using fields MXA?rjd0
* OX;bA^+}P
* @param page O60T.MM`
* @param content =[n !3M+X
*/ #wyceEa
public Result(Page page, List content){ zJX Z0yRT
this.page = page; AROHe
this.content = content; ToHx!,tDS
} MV5$e
5RT#H0/+
/** D1RQkAZS
* @return Returns the content. %DttkrhL
*/ T!x/^
publicList getContent(){ E2zL-ft.
return content; 4rhHvp
} @WazSL;N
ug%7}&
/** t]B`>SL3W
* @return Returns the page. nAQ[
-NbW,
*/ c44s@E
public Page getPage(){ #66i!}
return page; YIN* '!N
} `Am|9LOT
t ]BG)]
/**
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* @param content L 0Ckw},,
* The content to set. pW[TufTa
*/ q>%B @'
public void setContent(List content){ R*6TS"aL
this.content = content; / :$WOQ
} E?]$Y[KJKs
gYt=_+-
/** V dJ
* @param page Ktk?(49
* The page to set. 'A[PUSEE
*/ +P))*0(c_
publicvoid setPage(Page page){ }X9&!A8z
this.page = page; P*k n}:
} 3uw3[
SR1
} -']Idn6
3ko
h!q+
5B%KiE&p
xZ'C(~t
3=wcA/"!
2. 编写业务逻辑接口,并实现它(UserManager, O=K0KOj
\>\ERVEd
UserManagerImpl) z&9ljQ
iF
java代码: whN<{AG
>JNdtP8s/1
CL7_3^2qI
/*Created on 2005-7-15*/ \6AM?}v
package com.adt.service; !}}
)f/
K7s[Fa6J
import net.sf.hibernate.HibernateException; W
/v
&V#
0<V/[$}\D
import org.flyware.util.page.Page; $JOtUB{
E|-oUzt
import com.adt.bo.Result; =Fe4-B?I
{yNeZXA>
/** z}SJ~WY'[
* @author Joa [m! P(o
*/ e>_a
(
publicinterface UserManager { sC"w{_D@*4
#+<YFm\i
public Result listUser(Page page)throws x'-gvbj!
;~1xhpTk
HibernateException; w.rcYywI
B|o@|zF
} (<.\v@7HC
papMC"<g$
7Tp+]"bL
fNda&
C\{ KB@C\*
java代码: |A68+(3u
3K||(
1Y"9<ry
/*Created on 2005-7-15*/ jjrE8[
package com.adt.service.impl; ;P'5RCqj
{.U:Ce
import java.util.List; <0Y<9+g!
K:13t|
import net.sf.hibernate.HibernateException; `s69p'<;p
k v_t6 (qd
import org.flyware.util.page.Page; {^Q,G x(
import org.flyware.util.page.PageUtil; ;mI^J=V3
]*MVC/R,
import com.adt.bo.Result; %O!xrA{
import com.adt.dao.UserDAO; #t2N=3dOj
import com.adt.exception.ObjectNotFoundException; g3Q;]8Y&
import com.adt.service.UserManager; du0o4~-
ld"rL6
/** Ne;0fkO
* @author Joa 8_wh9
*/ d %FLk=]
publicclass UserManagerImpl implements UserManager { W9}
,f
r=37Q14v
private UserDAO userDAO; (:]+IjnE
%*K zP{
/** /:!l&1l:p
* @param userDAO The userDAO to set. K8&) kfyI
*/ qHheF%[\5
publicvoid setUserDAO(UserDAO userDAO){ 'cu14m_
this.userDAO = userDAO; oP
T)vN?
} ?x 0gI
48S
NI
/* (non-Javadoc) yIr0D6L
* @see com.adt.service.UserManager#listUser /]0SF_dZ
2&pE
(org.flyware.util.page.Page) FbMtor
*/ OVxg9
public Result listUser(Page page)throws 0$b4\.0>~
UlNiH
HibernateException, ObjectNotFoundException { <5Ll<0
int totalRecords = userDAO.getUserCount(); s1sn,?
if(totalRecords == 0) 7}MnvWP
throw new ObjectNotFoundException ;xUo(^t7>
`<P:ly.
("userNotExist"); FjizPg/|!
page = PageUtil.createPage(page, totalRecords); >S0kiGDV{
List users = userDAO.getUserByPage(page); ] ZP!y
returnnew Result(page, users); FSz<R*2
} m8
_yorz
M/lC&F(
} @+~>utr
R-<8j`[0
Wt@hST
v:Gy>&
/kw;q{>?o
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 G=Lg5`3;,
.x] pJ9
询,接下来编写UserDAO的代码: 9Nna-}e?W
3. UserDAO 和 UserDAOImpl: uzmYkBv
java代码: d@$bPQQ$,
Qc!3y>Y=_
F?jD5M08t/
/*Created on 2005-7-15*/ _cC!rq U1
package com.adt.dao; *ZLisq-f
9
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import java.util.List; KJS-{ed
gMZ+kP`
import org.flyware.util.page.Page; _NwHT`O[
LXJ;8uW2y
import net.sf.hibernate.HibernateException; 9@IL5 47V
NX8hFwR
/** WI*CuJU<zJ
* @author Joa 8lDb<i
*/ V?0IMc
publicinterface UserDAO extends BaseDAO { lup2>"?*
5}_=q;sZ
publicList getUserByName(String name)throws tux0}|[^'
T%FW|jKw
HibernateException; Z]tQmV8e
XHdhSFpm
publicint getUserCount()throws HibernateException; f[R~oc5P0
bWlYQ
publicList getUserByPage(Page page)throws _!vy|,w@e
=-r); d
HibernateException; y3j"vKG
d-m.aP)y:
} Q@PDhISa
]xoG{%vgb
C4gES"T
34"PtWbV>
\X!NoF
java代码: %{3q=9ii
7{w}0PMx
%\|{_]h}y
/*Created on 2005-7-15*/ QY<5o;m`
package com.adt.dao.impl; 6rD]6#D
E8R;S}PA
import java.util.List; S-3hLw&?
RjgJIVm(
import org.flyware.util.page.Page; :?y Ma$
WcM\4q@
import net.sf.hibernate.HibernateException; X's<+hK&
import net.sf.hibernate.Query; #pK"
^O*!
0b
n%L~KU
import com.adt.dao.UserDAO; b5
NlL`g
HOCj* O4
/** L@zhbWY
* @author Joa E]m?R 4
*/ aHYISjZ]>
public class UserDAOImpl extends BaseDAOHibernateImpl -/Wf iE
nSBhz
implements UserDAO { &dK!+
"dDrw ]P;
/* (non-Javadoc) 96#]P
* @see com.adt.dao.UserDAO#getUserByName 7m]J7 +4
fn5-Tnsq*
(java.lang.String) nP*% N|0
*/ N#-pl:J(
publicList getUserByName(String name)throws 1 JIU5u)
1(:!6PY
HibernateException { <;~u@^>
String querySentence = "FROM user in class rcMf1\
y@LiUe5
com.adt.po.User WHERE user.name=:name"; es x/{j;<u
Query query = getSession().createQuery SZ$WC8AX
v3XM-+Z4
(querySentence); 1 0c.#9$
query.setParameter("name", name); p nI=
return query.list(); )78T+7Kq
} 0jjtx'F
%+Z*-iX
/* (non-Javadoc) iI7ocyUv
* @see com.adt.dao.UserDAO#getUserCount() h4F%lGot
*/ 3/Z>W|w#w
publicint getUserCount()throws HibernateException { BL_0@<1X
int count = 0; /T(9:1/G
String querySentence = "SELECT count(*) FROM > l0H)W
#qDm)zCM
user in class com.adt.po.User"; $of2 lA
Query query = getSession().createQuery XM`
H@s7
yzzJKucVU:
(querySentence); YC56]Zp
count = ((Integer)query.iterate().next |rZMcl/
LfFXYX^
()).intValue(); $YcB=l
return count; w(
XZSE
} Nf3UVK8LtS
4sn\UuKyL
/* (non-Javadoc) ?7LvJ8
* @see com.adt.dao.UserDAO#getUserByPage x(eX.>o\
^IIy>
(org.flyware.util.page.Page) v}V[sIs}
*/ nM b@
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publicList getUserByPage(Page page)throws uZ-ZZE C
<9yh:1"X
HibernateException { u{\'/c7G
String querySentence = "FROM user in class S5y.H
zhFm2
com.adt.po.User"; |C<#M<
Query query = getSession().createQuery 25{_x3t^
2@GizT*mA
(querySentence); ^rP]B-)
query.setFirstResult(page.getBeginIndex()) +s"6[\H1d
.setMaxResults(page.getEveryPage()); S**eI<QFSk
return query.list(); wB \`3u4
} b7Z o~Z
:Ez,GA k
} $#u'XyA
NId.TaXh
5h6o}
h3k>WNT7
PzNPwd
至此,一个完整的分页程序完成。前台的只需要调用 G--X)h-
15<? [`:6
userManager.listUser(page)即可得到一个Page对象和结果集对象 Y-YuY
g""GQeR
的综合体,而传入的参数page对象则可以由前台传入,如果用 E8}evi
bG@2f"
webwork,甚至可以直接在配置文件中指定。 x6s|al
<]LljTm`i
下面给出一个webwork调用示例: $Emu*'
java代码: N~mr@rXC
FC,=g`Q!
Im/tU6ybV
/*Created on 2005-6-17*/
uu,F5<y[
package com.adt.action.user; sAL
]N][Y
31G0B_T
import java.util.List; Y6sX|~Zy
8iJB'#''*
import org.apache.commons.logging.Log; RK|*yt"f"
import org.apache.commons.logging.LogFactory; lYQ|NL():
import org.flyware.util.page.Page; G,|!&=Pe|E
wAprksZL#
import com.adt.bo.Result; V\<2oG
import com.adt.service.UserService; }a6t <m`V
import com.opensymphony.xwork.Action; VoZ{ I{>|
qVE0[ve
/** ~RuX2u-2&u
* @author Joa c!4F0(n4
*/ AT~,
publicclass ListUser implementsAction{ G!r)N0?_f
&R_7]f+%)
privatestaticfinal Log logger = LogFactory.getLog Q]xkDr?
\BXzmok
(ListUser.class); 8aP/vToa
mSxn7LG
private UserService userService; HN{c)DIm]
~dRstH7u
private Page page; cA
q3Gh
SE]5cJ'>
privateList users;
4F~^RR"
3Hom0g,V4
/* w#9KtW,tt
* (non-Javadoc) =L" 0]4K
* PFh ^Z L
* @see com.opensymphony.xwork.Action#execute() cu0IFNF}[
*/ =79R;|5
publicString execute()throwsException{ Z,38eQpM
Result result = userService.listUser(page); 0d9z8y
page = result.getPage(); 8I#ir4z#<
users = result.getContent(); ]19VEH
return SUCCESS; 2L^)k?9>g+
} @ivd|*?k0
&oS$<
/** _]>1(8_N
* @return Returns the page. FI$:R
*/ 'RK"/ZhqE
public Page getPage(){ MCT1ZZpPr
return page; Fr8GGN~/
} }#O!GG{
WVy'f|3;
/** { :tO
RF
* @return Returns the users. J/?Nf2L4
*/ pFd8p@m_2
publicList getUsers(){ "n!yK
return users; ;"wCBuXcu
} i/ilG3m>
_6ZjF>f
/** LmF ,en5
* @param page F3qK6Ah.
* The page to set. /9w>:i81
*/ !LI<%P)
publicvoid setPage(Page page){ ~9dpB>+
this.page = page; L8QWEFB|
} .gRj^pu
B )r-,M
/** A IP~A]T
* @param users az(<<2=
* The users to set. PLyity-L[7
*/ \n)',4mY
publicvoid setUsers(List users){ Zh<;r;2
this.users = users; )|F|\6:ne
} +T+@g8S
[]>'Dw_r
/** kz"uTJK
* @param userService 9Yx(u2PQ
* The userService to set. 'x!\pE-
*/ afEa@et'
publicvoid setUserService(UserService userService){ V)`2Kw
this.userService = userService; IY`p7 )#i
} =?fz-HB
} $<^t][{
Dm>"c;2
IU%|K~_n
fd\RS1[
):D"LC
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, ,^#Jw`w^
yGZsNd {a&
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 S(Yd.Sp
E
$@W~).!
么只需要: u/zBz*zh
java代码: ?{{w[U6NE
|cPHl+$nh.
o\IMYT
<?xml version="1.0"?> uepyH
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork qLN^9PdEE
,5}U
H
1.0//EN" "http://www.opensymphony.com/xwork/xwork- B`5<sW
g`7XE
1.0.dtd"> "F<CGSo
BX,)G HE
<xwork> yB*,)x0
@
<uH8Fivb
<package name="user" extends="webwork- +K57. n{
_u`YjzK
interceptors"> Mqf Ns<2
^mS |ff
<!-- The default interceptor stack name <B"sp r&1
(q>
TKM
--> /0h
*(nL
<default-interceptor-ref K2x[ApS#
kI\m0];KnQ
name="myDefaultWebStack"/> -Mt
5< s
[4Z 31v>
<action name="listUser" XpQ Ol
S&op|Z)1
class="com.adt.action.user.ListUser"> U=on}W3V2
<param u2V-V#jS
*2'8d8>R%]
name="page.everyPage">10</param> K"}fD;3
<result _]Hna <Ly
g*|j+<:7
name="success">/user/user_list.jsp</result> %\As
</action> 7io["zW
yzA05 npTl
</package> m7 =$*1k
GP|=4T}Bf
</xwork> R$awg SE
OW:*qY c;:
Nkdv'e\
=8kmFXo
US6_5>/
092t6D}
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 R$a<=
EP;/[O
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。 !QUY (
j=_rUc'Me
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 K~x,so
T5BZD
+Ta
weitDr6
wucdXj{%
l.[pnL D
我写的一个用于分页的类,用了泛型了,hoho
CI|lJ
kmuksT\)a
java代码: !,WGd|oJ
TBhM^\z
"q4tvcK.
package com.intokr.util; B{-7
D7ex{SVA)
import java.util.List; # kI>
R#(0C(FI^
/** F /b`[
* 用于分页的类<br> X>%nzY]m
* 可以用于传递查询的结果也可以用于传送查询的参数<br> W+XWS,(
* 7\u+%i;YZ
* @version 0.01 zd?@xno
* @author cheng J(
}2Ua_
*/ *OVB;]D3+
public class Paginator<E> { 6 Z/`p~e
privateint count = 0; // 总记录数 ;`9f<d#\
privateint p = 1; // 页编号 1C[9}}
privateint num = 20; // 每页的记录数 y!e]bvN
privateList<E> results = null; // 结果 )n/%P4l
FB=oGgwwq
/** 0MQ= Rt
* 结果总数 #F*|@
*/ JuRoeq.
publicint getCount(){ Vs>Pv$kW
return count; w7nt $L5
} <?jdNM
?5|;3N/zt
publicvoid setCount(int count){ $o6/dEKQ
this.count = count; Ur j*V0^
} C3AWXO ^
vNv?trw
/** ]!UYl
* 本结果所在的页码,从1开始 ~iw&^p|=K
* rvA>khu0/
* @return Returns the pageNo. ?M2(80
*/ ;#B(L=/
publicint getP(){ I8*VM3
return p; ;'!x
} !\]^c
#GsOE#*>T
/** SpH|<L3
* if(p<=0) p=1 e r"
w{
* ?0b-fL^^+l
* @param p z,HhSW?&^
*/ 7GA8sK
publicvoid setP(int p){ V>$( N/1
if(p <= 0) "SF0b jG9C
p = 1; Y~ ~Dg?e
this.p = p; 9#LMK 1ge
} ,OZ
.^YxhUH,G
/** p_r` "
* 每页记录数量 $QX$r N
*/ @xG&K{j
publicint getNum(){ Z\$HgG
return num; uL'f8Pqg
} f^%3zWp|-
PSrx!
/** }A9#3Y|F
* if(num<1) num=1 A`c22Ls]
*/ ,"qCz[aDN1
publicvoid setNum(int num){ ~C-Sr@ a?/
if(num < 1) IQQv+af5
num = 1; #ydold{F
this.num = num; #J5BHY~
} [hJ1]RW8
6fwNlC/9
/** jzvK;*N
* 获得总页数 {sTf4S\S
*/ n}p G&&;q
publicint getPageNum(){ NW|B|kc
return(count - 1) / num + 1; T+8Yd(:hX
} ,n|si#
<y 4(!z"
/** `RTxc
* 获得本页的开始编号,为 (p-1)*num+1 jKS j );
*/ , c.^"5
publicint getStart(){ _h%Jf{nu
return(p - 1) * num + 1;
gqaM<!]
} u#05`i:Z
(qcFGM22U
/** 2j\_svw'
* @return Returns the results. OT#@\/>
*/ +)jUA]hJ/
publicList<E> getResults(){ F)P:lvp<r
return results; QE]@xLz
} =g% L$b<i
b3NIFKw
public void setResults(List<E> results){ x/QqG1q
this.results = results; s|YH_1r
} h yrPu_
0
_!0\d#c
public String toString(){ 7KtU\u
StringBuilder buff = new StringBuilder "+DA)K
/4{WT?j
(); .EYL
buff.append("{"); SX3'|'-
buff.append("count:").append(count); dT`nR"
buff.append(",p:").append(p); $-_" SWG.
buff.append(",nump:").append(num); J%bNt)K}
buff.append(",results:").append \%-<O
cIug~ x>
(results); --HDE c|
buff.append("}"); KdNo'*;U]_
return buff.toString(); (}#&HE<
} b,~'wm8:A
G/x6zdk
} 2"0VXtv6
gI:g/ R
o:8ns m