Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 |)_R
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 -$q/7,os
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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 LKZI@i)
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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 aVb]H0
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分页支持类: KWUz]>Z
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java代码: *X #e
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package com.javaeye.common.util; ,W-0qN&%/
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import java.util.List; g2]-Q.
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publicclass PaginationSupport { $5IrM7i
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publicfinalstaticint PAGESIZE = 30; v\eBL&WK
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privateint pageSize = PAGESIZE; yDC97#%3u
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privateList items; QFPx4F7(e
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privateint totalCount; !;gke,fB
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privateint[] indexes = newint[0]; u^9c`
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privateint startIndex = 0; av?BpN"l
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public PaginationSupport(List items, int )'~FDw\6
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totalCount){ .B13)$C
setPageSize(PAGESIZE); pxx(BE
setTotalCount(totalCount); r\d:fot
setItems(items); <3}l8Z
setStartIndex(0); AF$ o>f
} ^Q>*f/.KN
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public PaginationSupport(List items, int xW =$j|
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totalCount, int startIndex){ 6hK"k
setPageSize(PAGESIZE); +df?N
setTotalCount(totalCount);
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setItems(items); o3qv945
setStartIndex(startIndex); %b;+/s2W
} j!\0Fyr
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public PaginationSupport(List items, int dO,05?q|
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totalCount, int pageSize, int startIndex){ fJ2{w[ne
setPageSize(pageSize); z-5#bOABW
setTotalCount(totalCount); 0)5Sx /5'
setItems(items); GuWBl$|+b
setStartIndex(startIndex); fm>K4\2
} yXx62J
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publicList getItems(){ bOMP8{H,
return items; sjgR \`AU
} ZPao*2xz
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publicvoid setItems(List items){ I;-5]/,
this.items = items; 9`xFZMd31A
} 3SDWR@x&
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publicint getPageSize(){ 3 ?F@jEQk
return pageSize; >-lL-%N_
} Qu FCc1Q
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publicvoid setPageSize(int pageSize){ f+Me dc~
this.pageSize = pageSize; W;dzLgc
} ]a#]3(o]}
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publicint getTotalCount(){ ~@ b}=+n
return totalCount; t[,T}BCy.
} ddDJXk)!0
*u'`XRJU/
publicvoid setTotalCount(int totalCount){ Wmxw!
if(totalCount > 0){ ]wpYxos
this.totalCount = totalCount; +A ?+G
int count = totalCount / Q 02??W
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pageSize; [KI`e
if(totalCount % pageSize > 0) Ko|xEz=
count++; OW}j4-~wL
indexes = newint[count]; zl
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for(int i = 0; i < count; i++){ ;n{j,HB
indexes = pageSize * dG>Wu o
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i; \Ntdl:fSw
} }|"*"kxi!
}else{ ,
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this.totalCount = 0; :YXQ9/iRr
} W?J*9XQ`
} ioa_AG6B
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publicint[] getIndexes(){ G!LNP&~
return indexes; j_uY8c>3\q
} PB<Sc>{U
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publicvoid setIndexes(int[] indexes){ a 8hv .43
this.indexes = indexes; (Zn3-t*
} q\y#
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publicint getStartIndex(){ `[ ` *@O(y
return startIndex; A;j$rGx
} FJ,\?ooGf
*5'6E'
publicvoid setStartIndex(int startIndex){ >\x_"oR
if(totalCount <= 0) G%8)6m'3
this.startIndex = 0; |DPpp/
elseif(startIndex >= totalCount) `)!2E6 =
this.startIndex = indexes obc^<ZD]
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[indexes.length - 1]; 7U
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elseif(startIndex < 0) \v
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this.startIndex = 0; 0R 5^p
else{ 2td|8vDA
this.startIndex = indexes FlA\Ad;v
l)PFzIz=V
[startIndex / pageSize]; vua1iN1
} CE7pg&dJ)i
} e9hVX[uq
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publicint getNextIndex(){ `Y({#U
int nextIndex = getStartIndex() + 9 c5G6n0
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}z<-
pageSize; ?]:EmP
if(nextIndex >= totalCount) g yH7((#i
return getStartIndex(); sEJ;t0.LX
else -anFt+f-
return nextIndex; dYew7
} ;0Ct\ [eh
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publicint getPreviousIndex(){ tqwk?[y}+l
int previousIndex = getStartIndex() - IJBJebqL
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pageSize; )>X|o$2
if(previousIndex < 0) . I&)MZ>n
return0; &~JfDe9IS
else g*r{!:,t
return previousIndex; VRQbf
} [cLU*:
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} >5~Zr$
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抽象业务类 ;GgQ@s@
java代码: 2*FWIHyf
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/** Dss/>!
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* Created on 2005-7-12 zEPx
*/ HHIUl,P
package com.javaeye.common.business; <j1d~XU}
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import java.io.Serializable; NtA|#"^
import java.util.List; ZG\ I1
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import org.hibernate.Criteria; <E7Vbb9*
import org.hibernate.HibernateException; j
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import org.hibernate.Session; \`Ph=lJO
import org.hibernate.criterion.DetachedCriteria; 6aF'^6+a
import org.hibernate.criterion.Projections; qvfAG 0p
import ekl?K~
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org.springframework.orm.hibernate3.HibernateCallback; o~.o^0Y
import $YGIN7_Gg
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org.springframework.orm.hibernate3.support.HibernateDaoS y%IG:kZ,
@(,{_c]
upport; '^oGDlkr H
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import com.javaeye.common.util.PaginationSupport; fdq^!MWTi
6PQJgki
public abstract class AbstractManager extends z5yb$-j
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HibernateDaoSupport { ]dGr1ncu
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privateboolean cacheQueries = false; wUIsi<Oj
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privateString queryCacheRegion; 32bkouq
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publicvoid setCacheQueries(boolean gM;)
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cacheQueries){ gGI#QPT`X
this.cacheQueries = cacheQueries; @^:7UI_
} Z*)y.i `
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publicvoid setQueryCacheRegion(String ~g
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queryCacheRegion){ mOz&6T<|
this.queryCacheRegion = p'%: M
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queryCacheRegion; K5)yM @cq
} .cH{WZ
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publicvoid save(finalObject entity){ 6Bq~\b^
getHibernateTemplate().save(entity); l#5~t|\
} B::4Qme
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publicvoid persist(finalObject entity){ ,.6J6{
getHibernateTemplate().save(entity); 68J 9T^84
} /XW&q)z-Hl
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publicvoid update(finalObject entity){ F; MF:;mM
getHibernateTemplate().update(entity); [`hE^chd
} {#w A!>.
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publicvoid delete(finalObject entity){ q2S!m6 !
getHibernateTemplate().delete(entity); kY'<u
} |Uy e>%*}4
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publicObject load(finalClass entity, :!+}XT7)/
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finalSerializable id){ >2| [EZ
return getHibernateTemplate().load ?x5wS$^q<
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(entity, id); `\ W
} , N@Yk.
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publicObject get(finalClass entity, HvqF@/xh
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finalSerializable id){ uXG`6|?
return getHibernateTemplate().get tL={ y*
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(entity, id); DD/>{kff
} &*G5J7%w
d%#!nq{vd
publicList findAll(finalClass entity){ m?D
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return getHibernateTemplate().find("from tp6csS,
(b/A|hl
" + entity.getName()); .)"_Q/q
} gnQo1q{ 4
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publicList findByNamedQuery(finalString rP^TN^bd|
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namedQuery){ @)W(q5)}9"
return getHibernateTemplate FGDGWcRw~
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().findByNamedQuery(namedQuery); "EcX_>
} |+Hp+9J
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publicList findByNamedQuery(finalString query, %Ycx C0S[
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finalObject parameter){ 93W
return getHibernateTemplate 7SgweZ}"
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().findByNamedQuery(query, parameter); ibd$%;bX3
}
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publicList findByNamedQuery(finalString query, e/"yGQu
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finalObject[] parameters){ <*s"e)XeqF
return getHibernateTemplate (O)\#%,@R
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().findByNamedQuery(query, parameters); mR{CVU
} Y7<zm}=(/
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publicList find(finalString query){ }xAie(
return getHibernateTemplate().find N$\ bg|v
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(query); KQG-2oW
} 7d&DrI@~
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publicList find(finalString query, finalObject r\$6'+Si
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parameter){ tigT@!`$Y
return getHibernateTemplate().find J>rka]*
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(query, parameter); "+=Pp
} L'zE<3O'3
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public PaginationSupport findPageByCriteria ,:D=gQ@`
a}:A, t<6
(final DetachedCriteria detachedCriteria){ v8ba~
return findPageByCriteria $4Z+F#mx
di~]HUZh)
(detachedCriteria, PaginationSupport.PAGESIZE, 0); j|:dYt`WM
} IByf_E;r
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public PaginationSupport findPageByCriteria "j{i,&Y$_
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(final DetachedCriteria detachedCriteria, finalint *IC^IC:
>[ eW">:>K
startIndex){ !Eq#[Gs
return findPageByCriteria \|CPR6I
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(detachedCriteria, PaginationSupport.PAGESIZE, yn SBVb!)
)uZoH8?
startIndex); #
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} C:]s;0$3'9
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public PaginationSupport findPageByCriteria EXuLSzQwv
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(final DetachedCriteria detachedCriteria, finalint D^Te%qnW
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pageSize, LO)GTyzvJ
finalint startIndex){ {Fbg]'FQ
return(PaginationSupport) ]eE 1n2
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getHibernateTemplate().execute(new HibernateCallback(){ P0^c?s"I
publicObject doInHibernate R (G2qi
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(Session session)throws HibernateException { 3gAR4
Criteria criteria = xq}-m!nX
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detachedCriteria.getExecutableCriteria(session); pz{'1\_+9
int totalCount = )zU:
]*qU+&
((Integer) criteria.setProjection(Projections.rowCount axmsrjW#
7paUpQit
()).uniqueResult()).intValue(); $.pTB(tO
criteria.setProjection NUCiY\td
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(null); GcT;e5D
List items = SxJ$b
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criteria.setFirstResult(startIndex).setMaxResults iv*V#J>
.}q]`<]ze
(pageSize).list(); `H\)e%]
PaginationSupport ps = &iNwvA%9D
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new PaginationSupport(items, totalCount, pageSize, hoenQ6N^:
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startIndex); .wmnnvtl,
return ps; wd[eJcQ ,
} ad9CsvW
}, true); 4WC9US-k
} C-m*?))go
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public List findAllByCriteria(final ,>n%
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DetachedCriteria detachedCriteria){ 8TE>IPjm
return(List) getHibernateTemplate {CtR+4KD
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().execute(new HibernateCallback(){ "xe=N
publicObject doInHibernate MoD?2J
v!9i"@<!
(Session session)throws HibernateException { D8%AV;-Y
Criteria criteria = qi(*ty
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detachedCriteria.getExecutableCriteria(session); qj!eLA-aD
return criteria.list(); WNs}sNSf
} 7\ypW $Ot
}, true); PY`L$e
} 1svi8wh
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public int getCountByCriteria(final \=;uu_v$
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DetachedCriteria detachedCriteria){ wG1l+^p
Integer count = (Integer) Ts9ktPlm
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getHibernateTemplate().execute(new HibernateCallback(){ DIaYo4
publicObject doInHibernate ~>Kq<]3~
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(Session session)throws HibernateException { JN4fPGbV
Criteria criteria = {^}0 G^
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detachedCriteria.getExecutableCriteria(session); :=Kx/E:1
return n((vY.NDV
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criteria.setProjection(Projections.rowCount Y
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()).uniqueResult(); S QY"OBo<e
} t
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}, true); u,1}h L
return count.intValue(); +/rH(Ni
} ,qQG;w,m
} #Yuvbb[
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用户在web层构造查询条件detachedCriteria,和可选的 >?lOE
-}^
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ua5?(,E`']
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PaginationSupport的实例ps。 R@iUCT^$
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ps.getItems()得到已分页好的结果集 cXnKCzSxZq
ps.getIndexes()得到分页索引的数组 QA#3bFZt1n
ps.getTotalCount()得到总结果数 i3VW1~ .8
ps.getStartIndex()当前分页索引 e:w&(is
ps.getNextIndex()下一页索引 .8WXC
ps.getPreviousIndex()上一页索引 jS.g]k
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 j;1 -p>z
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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 D*PYr{z'
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一下代码重构了。 &fC!(Oy
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我把原本我的做法也提供出来供大家讨论吧: GoM
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首先,为了实现分页查询,我封装了一个Page类: @|}BXQNd
java代码: +|iYg/2
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/*Created on 2005-4-14*/ ;Q;[*B=kE
package org.flyware.util.page; l_tw<`Ep
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/** #H?t!DU
* @author Joa !$;a[Te
* YgUH'P-
*/ b2,mCfLsv
publicclass Page { iIT8H\e
^ KK_qC
/** imply if the page has previous page */ |'O[7uT
privateboolean hasPrePage; TjMe?p
h%; e0Xz|
/** imply if the page has next page */ X?:o;wB
privateboolean hasNextPage; IP`6bMd
6qWdd&1
/** the number of every page */ \c v?^AI
privateint everyPage; {`=0 |oP}
h^9"i3H
/** the total page number */ 6VP`evan
privateint totalPage; im7nJQ^H$q
}v9\F-0>Q
/** the number of current page */ 7;@ST`cC
privateint currentPage; DZ7
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.d;Iht,[
/** the begin index of the records by the current @ V08U!
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query */ i,A#&YDl
privateint beginIndex; 4/ kv3rv
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/** The default constructor */ 2~[@_
public Page(){ *[ #;j$m
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} 8$s9(n-_Y
tM-^<V&
/** construct the page by everyPage VErv;GyV
* @param everyPage E!BPE>
* */ 7]xm2CHx5
public Page(int everyPage){ ]M/9#mD9~
this.everyPage = everyPage; t^]$!H
} fkSO( C)
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/** The whole constructor */ f<=Fsl
public Page(boolean hasPrePage, boolean hasNextPage, ;*ix~taL%
'7wd$rl
ih,%i4<}6m
int everyPage, int totalPage, LMi:%i%\
int currentPage, int beginIndex){ taGU
this.hasPrePage = hasPrePage; G22NQ~w8
this.hasNextPage = hasNextPage; Pq*s{
this.everyPage = everyPage; V.ht,
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this.totalPage = totalPage; @`tXKP$so
this.currentPage = currentPage; ES~^M840f
this.beginIndex = beginIndex; iwz
} HEL!GC>#
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/** 5D M"0
* @return -9RDr\&`(
* Returns the beginIndex. du$|lxC
*/ W$U0[^1
publicint getBeginIndex(){ RLlU"
sw+{
return beginIndex; |qZko[W}=
} b'MSkEiQG
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/** Go,N>HN
* @param beginIndex WN(ymcdYB
* The beginIndex to set. h)~=Dm
*/ Qk!;M|
publicvoid setBeginIndex(int beginIndex){ +`7KSwa
this.beginIndex = beginIndex; xq6cKtSv
} ,+`61J3W
(-]r~Ol^
/** q-nSLE+_;
* @return M"%Q&o/I
* Returns the currentPage. zR!o{8
*/ gtUUsQ%y .
publicint getCurrentPage(){ `1{N=!U(&
return currentPage; vvUSeG\n#j
} DAo~8H
iAT)VQ&
/** 8Ll[ fJZA
* @param currentPage LIg{J%
* The currentPage to set. + OV')oE
*/ R52I=
a5,*
publicvoid setCurrentPage(int currentPage){ zF5uN:-s
this.currentPage = currentPage; Oj<S.fi
} ["\;kJ.
+,~zWv1v
/** 0]D0{6x8
* @return 8|E'>+ D_-
* Returns the everyPage. JS}{ %(B
*/ XLMb=T~S
publicint getEveryPage(){ s1|/S\
return everyPage; q+B&orp
} !`!| Zw
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/** Y+K|1r
* @param everyPage Vh}SCUof'
* The everyPage to set. x0d~i!d
*/ 9qS"uj
publicvoid setEveryPage(int everyPage){ uKgZ$-'
this.everyPage = everyPage; R/"x}B1d
} -
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/** '`1CBU$
* @return (98Nzgxgx}
* Returns the hasNextPage. :eo
*/ CK,
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publicboolean getHasNextPage(){ {'16:dTJ
return hasNextPage; '!f5?O+E
} R |KD&!~Z
9&RFO$WH
/** 29XL$v],
* @param hasNextPage ?FfC
* The hasNextPage to set. Kscd}f)yx?
*/ Qr
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publicvoid setHasNextPage(boolean hasNextPage){ K't]n{$
this.hasNextPage = hasNextPage; bQ|V!mrN}
} ,lCgQ0}<
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/** y4+;z2'>
* @return RpLE
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* Returns the hasPrePage. "`6n6r42
*/ \.mI
publicboolean getHasPrePage(){ h*ZC*eV>
return hasPrePage; HHqwq.zIy
} &@ JvnO:
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/** Wu)>U
* @param hasPrePage tH'2gl
* The hasPrePage to set. YJ(*wByM
*/ lsN~*q?~]
publicvoid setHasPrePage(boolean hasPrePage){ VbBPB5 $q
this.hasPrePage = hasPrePage;
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} 43V}#DA@
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/** 2Pc%fuC
* @return Returns the totalPage. .$@R{>%U
* 86
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*/ E c s,$\
publicint getTotalPage(){ %v2R.?F8
return totalPage; H(Eh c
} I@\OaUGr+
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/** s`>[F@N7.o
* @param totalPage [5Lz/ix=
* The totalPage to set. _#vrb;.+
*/ Xy%p "b<
publicvoid setTotalPage(int totalPage){ imiR/V>N
this.totalPage = totalPage; 7 I>G{
} epgPT'^
sUPz/Z.h
} =~p>`nV
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 KF4PJi;*
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个PageUtil,负责对Page对象进行构造: Is+O
java代码: N!`e}Z6S
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c&L"N!4z
/*Created on 2005-4-14*/ d:yqj:
package org.flyware.util.page; ;j2vHU#q-
NzNA>[$[
import org.apache.commons.logging.Log; aN(|'uO@
import org.apache.commons.logging.LogFactory; LiKxq=K
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/** \rPbK+G.
* @author Joa rb{P :MX
* |hr]>P1
*/ jMpD+Mb
publicclass PageUtil { rSrIEP,c'
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privatestaticfinal Log logger = LogFactory.getLog 1IVuSp`{FU
tY
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(PageUtil.class); VcoOeAKL
*_ ?dVhxf
/** 0:b2(^]bg
* Use the origin page to create a new page RVeEkv[qp
* @param page Gdg"gi!4
* @param totalRecords Ge<nxl<Bd
* @return @]ao"ui@/
*/ : "1XPr
publicstatic Page createPage(Page page, int a+Ac[>
: >>@rF ,
totalRecords){ -+O
9<3ly
return createPage(page.getEveryPage(), `:axzCrCfR
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page.getCurrentPage(), totalRecords); 2+X\}s1vN
} *E{2J:`
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/** %RDI!e<e}
* the basic page utils not including exception P
3'O/!
x.q+uU$^
handler )&!&AlLn
* @param everyPage :kGU,>BN
* @param currentPage 4rrSb*
* @param totalRecords /d%=E
* @return page B7!3-1<k>
*/ !o$!Fr c
publicstatic Page createPage(int everyPage, int aE2.L;Tk?
t]-5 ]oI
currentPage, int totalRecords){ x*/S*!vx\
everyPage = getEveryPage(everyPage); oJfr +3I
currentPage = getCurrentPage(currentPage); F;]%V%F.X
int beginIndex = getBeginIndex(everyPage, -a-(r'Qc(
@*sWu_-Y%
currentPage); =%/)m:f!^
int totalPage = getTotalPage(everyPage, YIjTL!bA"
GI&h`X5,e
totalRecords); KVJ_E!i
boolean hasNextPage = hasNextPage(currentPage, f&
CBU
#B\"'8#
totalPage); & \f{E\A#
boolean hasPrePage = hasPrePage(currentPage); Y0X-Zqk'
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returnnew Page(hasPrePage, hasNextPage, )Eo)t>
everyPage, totalPage, hvaSH69*m
currentPage, 5;HH4?]p
Gy(=706
beginIndex); 87YyDWTn
} /gG"v5]
)-._FOZ6
privatestaticint getEveryPage(int everyPage){ =&:Y6XP
return everyPage == 0 ? 10 : everyPage; ^(FdXGs[
} ctGL-kp
GN2Sn`;
privatestaticint getCurrentPage(int currentPage){ lg&t8FHa;
return currentPage == 0 ? 1 : currentPage; &c,kQo+pA
} VzVc37Z>6
T~='5iy|
privatestaticint getBeginIndex(int everyPage, int q7E~+p(>(
=y!$/(H
currentPage){ R~6$oeWAw
return(currentPage - 1) * everyPage; c??mL4$'N
} ruy}/7uf
\*<d{gZ~
privatestaticint getTotalPage(int everyPage, int &oX>*6L
^cuc.g)c$?
totalRecords){ )h)]SF}
int totalPage = 0; (}2~<
% S os
if(totalRecords % everyPage == 0) <q@a~'Ai?!
totalPage = totalRecords / everyPage; sL$:"=
else )<tI!I][j
totalPage = totalRecords / everyPage + 1 ; S@/IQR
c.e2 M/
return totalPage; i ,/0/?)*_
} NN?`"Fww
PGoh1Uu
privatestaticboolean hasPrePage(int currentPage){ J
G{3EWXR
return currentPage == 1 ? false : true; Kh_Lp$'0uM
} 2_Z ? #Y
3(,?S$>
privatestaticboolean hasNextPage(int currentPage, rQ qW_t%
EU+S^SyZi
int totalPage){ =aTv! 8</
return currentPage == totalPage || totalPage == 1waTTT?"Ho
L}pt)w*V1j
0 ? false : true; 3z c U%*
} Zo~
{fjdr
XY3v_5~/1F
} ZNvEW
fd.^h*'mU
]%u@TK7
,]d/Q<
@W"KVPd
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 z+n,uHs
ybKWOp:O
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 lE(a%'36
W~7A+=&
做法如下: }xh$T'M8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 oc >{?.^
,1+y/{S
的信息,和一个结果集List: _dhgAx-H)h
java代码: #;2n;.a
8p:e##%
)u`[6,d
/*Created on 2005-6-13*/ R[hzMU}KB
package com.adt.bo; z?*w8kU&>
>]vlkA(
import java.util.List; IHv[v*4:
9^#c|
0T
import org.flyware.util.page.Page; 7%|~>
6"&6`f
/** "ozr+:#\
* @author Joa t^G"f;Ra+
*/ cmU1!2.1E
publicclass Result { 1oWED*B
heC/\@B
private Page page; $m-2HhqZ
(Hb:?(
private List content; 4i(JZN?
UKT%13CO4U
/** aGtf z)
* The default constructor oF1,QQ^dg
*/ D!Pq4'd(
public Result(){ 0vD7v
super(); S]Mw#O|
} ]rH\`0
T^k7o^N>
/** 9Hb6nm
* The constructor using fields Enn"hdI
* 1;Cyz)
* @param page LcTt)rs
f
* @param content O
@j} K4
*/ BMG3|N^
public Result(Page page, List content){ xg;+<iW
this.page = page; YSic-6z0Ms
this.content = content; lJ}_G>GJ
} DpvI[r//'*
L(|N[#
/** c]n1':FT"
* @return Returns the content. 7'W%blg!V
*/ {byBcG
publicList getContent(){ g+Sbl
return content; <oT^ A|JFj
} Vr`R>S,-
NflD/q/ L
/** \F/hMXDlJ
* @return Returns the page. rrBsb -
*/ xSsa(b
public Page getPage(){ --HZX
return page;
H Y&DmE
} '$ =>
Mh:L$f0A%O
/** l3Q(TH ~I
* @param content #*K}IBz
* The content to set. 8<pzb}xK
*/ p6#g;$V$
public void setContent(List content){ lhAX;s&9
this.content = content; j7$e28|_n
}
!sQY&*
ZojIR\F^
/** j<VFn~*_
* @param page v1+3}5b'uF
* The page to set. wsZF;8u t
*/ -.u]GeMy
publicvoid setPage(Page page){ :t8b39
this.page = page; @"Fme-~
} j,lT>/
} S1Wj8P-
*`ua'"="k
n22zq6m
)_syZ1j
aeFe!`F
2. 编写业务逻辑接口,并实现它(UserManager, 6}[I2F_^
la0BiLzb]
UserManagerImpl) ([T>.s
java代码: "d#Y}@*~o
#~}nFY.
Wuc S:8#|
/*Created on 2005-7-15*/ e6R}0w~G
package com.adt.service; _~IR6dKE
X0bN3N
import net.sf.hibernate.HibernateException; LtWP0@JA
n'wU;!W9
import org.flyware.util.page.Page; GK)?YM
8_BV:o9kL
import com.adt.bo.Result; J>wt(] y
W=^#v
/** 8uc1iB
* @author Joa +Mo9kC
*/ ov`h
publicinterface UserManager { p
Dx1z|@z
&=Ar
public Result listUser(Page page)throws Z&Pg"a?\
bH7X'%r
HibernateException; jVv0ST*z
ieDk ;
} \r;#g{
_
Vwg|K|
L[oui,}_
D.B.7-_8
s@&`f{
java代码: rdl;M>0@
y I HXg#
dpAjR
/*Created on 2005-7-15*/ Su
586;\
package com.adt.service.impl; #I{h\x><?
0bceI
import java.util.List; .0S~872
8'r2D+Vwm
import net.sf.hibernate.HibernateException; 1n >X[!
8x
AF;)#T<
import org.flyware.util.page.Page; B8.Pn
import org.flyware.util.page.PageUtil; ]
bM)t<
l4 D+Y
import com.adt.bo.Result; [pC$+NX
import com.adt.dao.UserDAO; 6Z>FTz_
import com.adt.exception.ObjectNotFoundException; !o5
W
import com.adt.service.UserManager; 2 Wt> Mi
|4)>:d
/** MW! srTQ_
* @author Joa PlU*X8
*/ s1MErd
publicclass UserManagerImpl implements UserManager { V/%>4GYnC
1t:Q_j0Ym
private UserDAO userDAO; **w!CaqvY
H7z,j}l
/** d?s<2RkPT
* @param userDAO The userDAO to set. RY]#<9>M
*/ #o=y?(
publicvoid setUserDAO(UserDAO userDAO){ 14Xqn8uOW
this.userDAO = userDAO; N+m)/x
=:
} oiF}?:7Q7
xHUsFms
/* (non-Javadoc) .GsV>H
* @see com.adt.service.UserManager#listUser Gy9$wH@8
j2Cks_$:
(org.flyware.util.page.Page) nG,A@/N
*/ 49rf7NT-g
public Result listUser(Page page)throws )_+rU|We
^`*9QjY
HibernateException, ObjectNotFoundException { Y'c>:;JEe
int totalRecords = userDAO.getUserCount();
|XT)QK1
if(totalRecords == 0) M`. tf_x
throw new ObjectNotFoundException !S^AgZ~
T m_bz&Q
("userNotExist"); 0C =3dnp6
page = PageUtil.createPage(page, totalRecords); v/Py"hQ
List users = userDAO.getUserByPage(page); j5K]CTz#
returnnew Result(page, users); x*![fK
} ~3Lg"I
i'a?kSy
} @XgKYm
2"0es40;0
7FzA*
q+Lr"&'Q
t|H^`Cv6
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 cQ/5qg
f1`gdQ)H
询,接下来编写UserDAO的代码: !Z`j2
e}
3. UserDAO 和 UserDAOImpl: aUzBV\Yd}
java代码: :V1W/c
MC?,UDNd%
gcE|#1>
/*Created on 2005-7-15*/ J,V9k[88
package com.adt.dao; bP8Sj16q
O;z,qo X
import java.util.List; ~rlB'8j(
1/RsptN"v
import org.flyware.util.page.Page; 5A%w 8Qv
j K!Au
import net.sf.hibernate.HibernateException; FemCLvu
PpGL/,]X
/** ;'?l$
._
* @author Joa G,$PV
e*
*/ ZO!I.
publicinterface UserDAO extends BaseDAO { Qt iDTr
<A[E:*`*
publicList getUserByName(String name)throws R%Qf7Q
:H7D~ n
HibernateException; "JVkVp[5D+
]=.\-K
publicint getUserCount()throws HibernateException; ?i)f^O
l,R/Gl
publicList getUserByPage(Page page)throws 0)%YNaskj
P<PJ)>
HibernateException; E4gYemuN
-u&6X,Oq\u
} +1Vjw'P
CAWA3fcQp
iocI:b<
03xa'Of>
O?NeSx1
java代码: N/]o4o
Vx(B{5>Vu
RSr
%n1
/*Created on 2005-7-15*/ I[=j&rK`
package com.adt.dao.impl; @|Fg,N<Y]
)!Jc3%(B
import java.util.List; 3 ,>0a
pwO>h>ik
import org.flyware.util.page.Page; sJ#4(r`
/|r^W\DV&x
import net.sf.hibernate.HibernateException; -|kA)M[
import net.sf.hibernate.Query; TK5K_V*7
j;%-fvd;
import com.adt.dao.UserDAO; oE<`VY|
I'\kFjc
/** QZ4v/Ou
* @author Joa x1Lb*3Fe
*/ +~'865 {
public class UserDAOImpl extends BaseDAOHibernateImpl ICuF %
P1zKsY,l$<
implements UserDAO { rW0kA1=E
3j,Q`+l/6d
/* (non-Javadoc) A54N\x,
* @see com.adt.dao.UserDAO#getUserByName Dakoqke
>C7r:%
(java.lang.String) xgABpikC^
*/ rE iKi
publicList getUserByName(String name)throws WxW7qt
~;O v-^tp
HibernateException { 3Th'p aMG
String querySentence = "FROM user in class <!L>Exh&r
bQE};wM,
com.adt.po.User WHERE user.name=:name"; k xP-,MD
Query query = getSession().createQuery ?bPRxR
"XB[|#&
(querySentence); 0rh]]kj
query.setParameter("name", name); O>SLOWgha
return query.list(); x6(~;J
} t]>Lh>G
&Q+Ln,(&L
/* (non-Javadoc) e@c0WlWa
* @see com.adt.dao.UserDAO#getUserCount() \x)n>{3C
*/ :Mb%A
publicint getUserCount()throws HibernateException { anIAM
int count = 0; E8>Rui@9
String querySentence = "SELECT count(*) FROM >G);j@Q
g1XZ5P} f
user in class com.adt.po.User"; zEs>b(5u
Query query = getSession().createQuery q+P|l5_
t
aT_&x@x
(querySentence); 8S>&WR%jH]
count = ((Integer)query.iterate().next Fp@TCPe#
6^uq?
()).intValue(); T^:UBjK6t{
return count; kdCUORMK
} fYp'&Btb]x
@[5xq
/* (non-Javadoc) J%x6
* @see com.adt.dao.UserDAO#getUserByPage =.y~f A!
D<|qaHB=
(org.flyware.util.page.Page) e"/;7:J5\
*/ N e#WI'
publicList getUserByPage(Page page)throws +lJG(Qd
p+l !6
HibernateException { cU0s
p
String querySentence = "FROM user in class 9[1`jtm
3mYiQ2
com.adt.po.User"; i%ZW3MrY~
Query query = getSession().createQuery 5V5%/FUm
TftHwe):V
(querySentence); +SsK21f"r
query.setFirstResult(page.getBeginIndex()) |o,8V p
.setMaxResults(page.getEveryPage()); I([!]z
return query.list(); k:JrHBKv\
} k9$K}
gT$Ju88
} <.pU,T/
eAX
)^q
jZh';M8"
rrQQZ5fh b
9UKp?SIF
至此,一个完整的分页程序完成。前台的只需要调用 hc~s"Atck
D!.[q -<
userManager.listUser(page)即可得到一个Page对象和结果集对象 u`y><w4i
[!} :KD2yX
的综合体,而传入的参数page对象则可以由前台传入,如果用 )ap_Z6
+
` s@
webwork,甚至可以直接在配置文件中指定。 #?q&r_@@
j;s"q]"x]
下面给出一个webwork调用示例: 8#(Q_
java代码: V+Cwzc^j
/DQc&.jK
L !=4N!j
/*Created on 2005-6-17*/ _7IKzUn9g[
package com.adt.action.user; )N=NR2xBZ
_{R=B8Zz\
import java.util.List; '&.#
:>D[n1v
import org.apache.commons.logging.Log; R<sJ^nx
import org.apache.commons.logging.LogFactory; t'BLVCu
import org.flyware.util.page.Page; (7XCA,KTGI
W5?yy>S6N
import com.adt.bo.Result; V6t,BJjS
import com.adt.service.UserService; `kbSu}
import com.opensymphony.xwork.Action; 6T+FH;h
5O~HWBX.
/** Mr?Xp(.}G
* @author Joa j6>.n49_
*/ HHq_P/'
publicclass ListUser implementsAction{ G2t;DN(
*NkA8PC
privatestaticfinal Log logger = LogFactory.getLog 5WC+guK7
[|P!{?A43|
(ListUser.class); A;/-u<f
vw>2(K=e1
private UserService userService; FL(6?8zK
(S xR`QP?,
private Page page; Mu{;vf|j
Nc+,&R13m
privateList users; $-#Yl&?z9
58%#DX34M
/* Q -MQ9'
* (non-Javadoc) X>NhZ5\
*
1WY/6[
* @see com.opensymphony.xwork.Action#execute() S/Fkw4%
*/ 2>86oP&
publicString execute()throwsException{ mjWU0Gh%*
Result result = userService.listUser(page); 2 Yp7
page = result.getPage(); #{k|I$
users = result.getContent(); [%9noB
return SUCCESS; /%0<p,T
} i/~1F_
S}$r>[t
/** 9:`(Q3Ei
* @return Returns the page. *Ho/ZYj3
*/ (T!9SU
public Page getPage(){ .C2TQ:B, .
return page; kGd<5vCs
} iXjo[Rz^C
krsYog(^z
/** ,WJH}(h"D
* @return Returns the users. TjHwjRa
*/ Si_%Rr&jW
publicList getUsers(){ ZQ_xDKqRV
return users; z)z{3rR|PW
} ccLq+a|
9G{;?c
/** a@\D$#2r
* @param page Pu"R,a
* The page to set. K4]g[z
*/ rS4@1`/R
publicvoid setPage(Page page){ vG;zJ#c
this.page = page; dbOdq
} FXzFHU/dP
:6zG7qES3
/** H ,+?
t
* @param users xdf82)
* The users to set. =JKv:</.G
*/ mt5KbA>nU
publicvoid setUsers(List users){ /9zE^YcT
this.users = users; 6ezS {Q
} Tszp3,]f
34wkzu
/** *^RmjW1I
* @param userService $ &P>r
* The userService to set. lY{FSGp
*/ (tCUlX2
publicvoid setUserService(UserService userService){ vfl5Mx4
this.userService = userService; #% of;mJv
} srYJp^sC
} 7ULqo>j
-K
rxMi
[Z~ 2
ithewup
n Ps7c %
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, /F4pb]U!*
81hbk((
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 [74F6Qp
H(Q.a=&4!p
么只需要: 7<jZ`qdq_
java代码: =xNv\e
/Nr*`l
hgLj<
<?xml version="1.0"?> ?{U
m
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork %e`$p=m
5Q 'i2*j
1.0//EN" "http://www.opensymphony.com/xwork/xwork- zfwS
&BtK($
1.0.dtd"> @#P,d5^G
vjQb%/LWl
<xwork> ?Q-h n:F)
Kh4$ wwn
<package name="user" extends="webwork- +<}0|Xl&
NM0tp )h
interceptors"> ZxlAk+<]
*J+_|_0nlW
<!-- The default interceptor stack name f m(e3]
hFk3[zTy
--> \=0Vuz
<default-interceptor-ref <`jLY)sw
,(.MmP`
name="myDefaultWebStack"/> (u]N
MB%Q WU
<action name="listUser" \~BDm
f8SL3+v
class="com.adt.action.user.ListUser"> Dk+&X-]6x5
<param f+|$&p%
quvanxV-L
name="page.everyPage">10</param> Up:<=Kgci
<result Gcb|W&
E;d7ch
name="success">/user/user_list.jsp</result> @q"m5
</action> *loOiM\5a
-F=v6N {
</package> @xeAc0.^
"Tm[t?FMbe
</xwork> ,^gyH
\
R |f~>JUF
PG8^.)]M
M\Gdn92pd
k{V E1@
(ewe"N+
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 kPQtQh]y%
e5.h ?
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。 .`7cBsXH
d/}SAvtt
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 etd&..]J
*26334B.R
{CR 5K9
50
A^bbid
T \CCF
我写的一个用于分页的类,用了泛型了,hoho 8scc%t7
YPzU-:3
java代码: ;SwMu@tg
DAwqo.m
gPu2G/Y
package com.intokr.util; sHc Td>xS
~V/?H!r'{}
import java.util.List; 2kv7UU#q2
`)qVF,Z}
/** DfV~!bY
* 用于分页的类<br> oG7q_4+&
* 可以用于传递查询的结果也可以用于传送查询的参数<br> wBQF~WY
* *xE,sj+(
* @version 0.01 >|6iR%"f#
* @author cheng U:MPgtwe
*/ +525{Tj
public class Paginator<E> { @Kf_z5tm:
privateint count = 0; // 总记录数 hLDA]s
privateint p = 1; // 页编号 lNv".Y=l
privateint num = 20; // 每页的记录数 $7QoMV 8V
privateList<E> results = null; // 结果 zE)~0v4
H'MJ{r0,
/** MG /,==
* 结果总数 ^'p|!`:
*/ A~Xq,BxCV
publicint getCount(){ zZiJ 9 e
return count; m=Q[\.Ra
} <*t4D-os
U!XS;a)
publicvoid setCount(int count){ A:y.s;<L0
this.count = count; XE3'`D!
} ,Rx{yf]k
?0_7?yTR/
/** .bVmqR`
* 本结果所在的页码,从1开始 IScRsxFb
* w#N?l!5
* @return Returns the pageNo. -o+74=E8[?
*/ =pA
IvU
publicint getP(){ ^E6d`2w-
return p; 'a^{=+
} pG^}Xf2a
>K# ,cxY
/** =`Y.=RL+'n
* if(p<=0) p=1 Y~)T
* \@}#Gez
* @param p ri1C-TJM)
*/ q8:{Nk
publicvoid setP(int p){ E42eOGp9i
if(p <= 0) X%bFN
p = 1; 0t#g}
this.p = p; ]O{u tm
} .Hc(y7HV
okq[ o90
/** \V2,pi8'v
* 每页记录数量 g\GdkiIj
*/ H0a/(4/xg
publicint getNum(){ CzV(cSS9-
return num; {FN;'Uc
} iqhOi|!
G5D2oQa=8
/** k>E`s<3
* if(num<1) num=1 |3K)$.6~
*/ .$",
*d
publicvoid setNum(int num){ >QHo@Zqj(
if(num < 1) w62=06`@
num = 1; Q,Z*8FH=
this.num = num; XYx6V
} gPzL*6OSA
h{lDxOH*
/** 44\>gI<
* 获得总页数 AGYm';z3
*/ ,}xbAA#
publicint getPageNum(){ P6Bl
*@G
return(count - 1) / num + 1; 9Q W&$n^
} kC$&:\Rh
u)Q;8$`
/** )a=/8ofe
* 获得本页的开始编号,为 (p-1)*num+1 ^D@b;EyK
*/ ig 0u^BC
publicint getStart(){ Q36)7=at
return(p - 1) * num + 1; iA!7E;o
} :L0/V~D
Lc<eRVNd,
/** %lr|xX
* @return Returns the results. 'f/Lv@]a
*/ lH|LdlX
publicList<E> getResults(){ nzX@:7g
return results; R.j1?\
} |m,VTViv;i
?p[O%_Xf
public void setResults(List<E> results){ r^HAa GpC
this.results = results; j2h[70fWC
} w W$(r-
ovf/;Q/}
public String toString(){ WW@"Z}?k
StringBuilder buff = new StringBuilder &jV_"_3n
~9D~7UR
(); ^_p%Yv
buff.append("{"); d0er^ ~
buff.append("count:").append(count); %u p}p/?
buff.append(",p:").append(p); 1'6cGpZY
buff.append(",nump:").append(num); *! :QdWLq
buff.append(",results:").append -%IcYzyA
7Tf]:4Y"
(results); q}L+/+b
buff.append("}"); m:`@?n~..
return buff.toString(); Gie@JX
} <64HveJ
tPuut\ee
} }0=<6\+:`
lm'Zy"~::
#~?kYCtC)