Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 -lY,lC>{
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 H9\,;kM)
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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 D_N0j{E
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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 HUFm@?
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分页支持类: -k?K|w*X
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java代码: bA-/"'Vp9
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package com.javaeye.common.util; @tX8M[.eA
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import java.util.List; qyKI.X3n*
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publicclass PaginationSupport { o5E5s9n
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publicfinalstaticint PAGESIZE = 30; 0{OafL8&l
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privateint pageSize = PAGESIZE; oO3X>y{gN
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privateList items; ]@I>OcH
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privateint totalCount; {/|tVc63
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privateint[] indexes = newint[0]; z',f'3+
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privateint startIndex = 0; ,rNv}
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public PaginationSupport(List items, int o(gV;>I
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totalCount){ ~<Z7\yS)
setPageSize(PAGESIZE); .T1n"TfsGO
setTotalCount(totalCount); )GKY#O09x9
setItems(items); wpI"kk_@@
setStartIndex(0); [w*]\x'S
} S^x?<kYQau
*=}\cw\A
public PaginationSupport(List items, int nK)hv95i_
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totalCount, int startIndex){ aH&Efz^
setPageSize(PAGESIZE); RhWW61!"
setTotalCount(totalCount); g5;Ig
setItems(items); kxLWk%V
setStartIndex(startIndex); m++=FsiX=
} Lng@'Yr
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public PaginationSupport(List items, int C)mR~Ey
\ 62!{
totalCount, int pageSize, int startIndex){ d3]<'B:nb
setPageSize(pageSize); {pXqw'"1.
setTotalCount(totalCount); J)EL<K$Z[
setItems(items); YmwXA e:
setStartIndex(startIndex); O|nLIfT
} )!lx'>0>
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publicList getItems(){ FOAXm4"
return items; 4$y P_3
} Mt*V-`+\
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publicvoid setItems(List items){ _/J`v`}G
this.items = items; 3=("vR`!
} 'A,)PZL9i
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publicint getPageSize(){ i~LY
return pageSize; L%<DLe^P`l
} GvBmh .
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publicvoid setPageSize(int pageSize){ ^x2@KMKXZ
this.pageSize = pageSize; Ki>XLX,er=
} o;u~Yg
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publicint getTotalCount(){ (e#f
return totalCount; .JBTU>1]_n
} *LEI@
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publicvoid setTotalCount(int totalCount){ y" |gC!V}
if(totalCount > 0){ C[,&Y&`j
this.totalCount = totalCount; O Cnra
int count = totalCount / bZ#5\L2
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pageSize; q8}he~a
if(totalCount % pageSize > 0) nwVW'M]r
count++; 4>Y*owa4
indexes = newint[count]; A: O"N
for(int i = 0; i < count; i++){ zJ_y"bt
indexes = pageSize * SPp|/ [i7
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i; HLC I
} q<K/q"0-l
}else{ NFPWh3),f
this.totalCount = 0; lMgPwvs'
} v\+`n^=
} 3pe1"maP
p/HGI)'
publicint[] getIndexes(){ VHG}'r9KC%
return indexes; A@eR~Kp
^
} 30O7u3Zrb
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publicvoid setIndexes(int[] indexes){ o%OwKp
s
this.indexes = indexes; xkQT#K=i
} "-P z2QJY
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publicint getStartIndex(){ d(K}v\3!
return startIndex; x2f=o|]D'
} ,'n`]@0?\
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publicvoid setStartIndex(int startIndex){ FQ0PXYh
if(totalCount <= 0) MS]Q\g}U
this.startIndex = 0; dsg-;*%
elseif(startIndex >= totalCount) /I:&P Pff
this.startIndex = indexes i]Bu7Fuu
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[indexes.length - 1]; Ph)>;jU
elseif(startIndex < 0) e|q~t
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this.startIndex = 0; *-S?bv,T'
else{ yG;@S8zC
this.startIndex = indexes mNsd&Rk'
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[startIndex / pageSize]; {B4.G8%Z
} h@TP=
} :sttGXQX
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publicint getNextIndex(){ 7.]H9
int nextIndex = getStartIndex() + yY]E~
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pageSize; HQnc`2
if(nextIndex >= totalCount) G=LK
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return getStartIndex(); @)wsHW%cjz
else =mSu^q(l
return nextIndex; 'hFL`F*
} ?<T=g
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publicint getPreviousIndex(){ Ro;I%j
int previousIndex = getStartIndex() - mW~*GD~r
o$Y#C{wC%
pageSize; cI&XsnY
if(previousIndex < 0) Mcq!QaO}&
return0; 1vS-m x
else [,{Nu EI
return previousIndex; ";/ogFi
} *U$%mZS]1
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} FNw]DJ]
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抽象业务类 =\mJ5v"hA
java代码: TF 80WMt
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/** Dy:r)\KX
* Created on 2005-7-12 h6}rOchj
*/ <8YvsJ
package com.javaeye.common.business; ah,"c9YX
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import java.io.Serializable; <\eRa{ef
import java.util.List; { `xC~B h
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import org.hibernate.Criteria; Xq<_r^
import org.hibernate.HibernateException; dkqyn"^
import org.hibernate.Session; bcT'!:
import org.hibernate.criterion.DetachedCriteria; ;rNX
import org.hibernate.criterion.Projections; c|Z6p{)V
import GB;_!69I
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org.springframework.orm.hibernate3.HibernateCallback; Yh Ow0 x
import JcMl*k
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org.springframework.orm.hibernate3.support.HibernateDaoS 3w"_Onwk
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upport; RS@[ +! :t
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import com.javaeye.common.util.PaginationSupport; 2dK:VC4U
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public abstract class AbstractManager extends ;/kmV~KG
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HibernateDaoSupport { -8R SE4)
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privateboolean cacheQueries = false; oX'@,(6)
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privateString queryCacheRegion; 3_.%NgES|
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publicvoid setCacheQueries(boolean r8!pk~R5]
}8s&~fH
cacheQueries){ %;|dEY
this.cacheQueries = cacheQueries; Qc=-M'9
} $~VIx% h
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publicvoid setQueryCacheRegion(String &0H_W xKeB
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queryCacheRegion){ E}THG=6
this.queryCacheRegion = hztqZ:
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queryCacheRegion; [_}8Vv&6
} *xITMi
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publicvoid save(finalObject entity){ WJ LqH<
getHibernateTemplate().save(entity); _%23L|
} Mz86bb^J
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publicvoid persist(finalObject entity){ VDZOJM)(
getHibernateTemplate().save(entity); TAqX
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} l ?YO!$
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publicvoid update(finalObject entity){ 3g5r}Ug
getHibernateTemplate().update(entity); l;&kX6 w
} Do5.
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publicvoid delete(finalObject entity){ ,el[A`b
getHibernateTemplate().delete(entity); !w@i,zqu
} h%NM%;"H/
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publicObject load(finalClass entity, ^~6gkS
}
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finalSerializable id){ d @ l
return getHibernateTemplate().load p L^3*B.Nr
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(entity, id); dV16'
} z@V9%xF-3
t* p%!xsH
publicObject get(finalClass entity, /Ahh6=qQY
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finalSerializable id){ 0\s&;@xKk
return getHibernateTemplate().get rvK%m_r
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(entity, id); @; I9e
} 9\T9pjdZE
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publicList findAll(finalClass entity){ $<Y%4LI
return getHibernateTemplate().find("from 2JcP4!RD
3 `mtc@*
" + entity.getName()); >,I'S2_Zl
} &\Lu}t7Ru
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publicList findByNamedQuery(finalString 8G9( )UF.
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namedQuery){ #};Zgixo$
return getHibernateTemplate &
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065 =I+Vo
().findByNamedQuery(namedQuery); 0PsQ
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} zA:q/i
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publicList findByNamedQuery(finalString query, m|t\w|B2
N:S2X+}(
finalObject parameter){ P=\Hi.]%
return getHibernateTemplate g W9`k,U
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().findByNamedQuery(query, parameter); rKd|s7l
} mZmEE2h
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publicList findByNamedQuery(finalString query, r4fg!]J;
)0"T?Ivp]
finalObject[] parameters){ pjFj{
return getHibernateTemplate @Y>PtA&w*
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().findByNamedQuery(query, parameters); H*P+>j&
} Zk>m!F>,p
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publicList find(finalString query){ t~nW&]E
return getHibernateTemplate().find %+;l|Z{Uf
moh,a B#
(query); Kv<mDA!
} Y6d~hLC
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publicList find(finalString query, finalObject ! hEZV&y
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parameter){ m_BpY9c]5
return getHibernateTemplate().find 7Kb&BF|Q
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(query, parameter); Aayd3Ph0%
} 1$6
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public PaginationSupport findPageByCriteria o@]n<ZYo
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(final DetachedCriteria detachedCriteria){ k B4Fz
return findPageByCriteria 8Gy*BpmJn
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); @
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} SW+;%+`
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public PaginationSupport findPageByCriteria ,:MUf]Ky
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(final DetachedCriteria detachedCriteria, finalint o{n#f?EA
~ _tK.m3
startIndex){ }J92TV
return findPageByCriteria `T ^0&#
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(detachedCriteria, PaginationSupport.PAGESIZE, TBba3%
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startIndex); PYY<
} !r/~D |
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public PaginationSupport findPageByCriteria h4MBw=Tz~
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(final DetachedCriteria detachedCriteria, finalint rg]b$tL~
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pageSize, _5O~]}
finalint startIndex){ (nuTfmt>
return(PaginationSupport) 7.g,&s%q
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getHibernateTemplate().execute(new HibernateCallback(){ _^zs(
publicObject doInHibernate l[m*csDk"
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(Session session)throws HibernateException { },Grg~l
Criteria criteria = O&~
@ior
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detachedCriteria.getExecutableCriteria(session); 8oRq3 "
int totalCount = wN/v-^2
*8yC6|wL?
((Integer) criteria.setProjection(Projections.rowCount 0o BAJP
xS+xUi
()).uniqueResult()).intValue(); TeR bW
criteria.setProjection Gi$\th,
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(null); x;~@T9.
List items = \9od*y
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criteria.setFirstResult(startIndex).setMaxResults p-rQ'e
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(pageSize).list(); ; 4/ n~
PaginationSupport ps = _,UYbD\[J}
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new PaginationSupport(items, totalCount, pageSize, TM_bu
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startIndex); !O'p{dj][
return ps; Xqew~R^MP
} vMn$lT@
}, true); {BaPK&x,
} w(
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public List findAllByCriteria(final <4 /q5*&
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DetachedCriteria detachedCriteria){ fLSDt(c',
return(List) getHibernateTemplate (r}StR+
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().execute(new HibernateCallback(){ z\K%
publicObject doInHibernate o@aXzF2
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(Session session)throws HibernateException { N#R8ez`
Criteria criteria = BZXee>3"
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detachedCriteria.getExecutableCriteria(session); 9fM=5
return criteria.list(); ,5 3`t
} H&k&mRi
}, true); ;4v`FC>
} HoWK#Nz\
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public int getCountByCriteria(final G#uB%:)&0u
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DetachedCriteria detachedCriteria){ ?"?AH/E D
Integer count = (Integer) n}4q2x"
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getHibernateTemplate().execute(new HibernateCallback(){ XJq]l6a:
publicObject doInHibernate Uz]=`F8
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(Session session)throws HibernateException { |&bucG=
Criteria criteria = hW;n^\lF#e
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detachedCriteria.getExecutableCriteria(session); 9]/:B8k
return x&EMg!
9c{ ~$zJW
criteria.setProjection(Projections.rowCount bV#j@MJ~0
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()).uniqueResult(); dWhqu68_
} ;~`/rh
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}, true); 1$m{)Io2(
return count.intValue(); uOd1:\%*
} Q(BZg{
} e\*(F3r
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用户在web层构造查询条件detachedCriteria,和可选的 rj1%IzaXU^
5.kKg=a
startIndex,调用业务bean的相应findByCriteria方法,返回一个 k6\&[BQs
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PaginationSupport的实例ps。 N7;kWQH
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ps.getItems()得到已分页好的结果集 *ck'vV'@
ps.getIndexes()得到分页索引的数组 ;L%\[H>G
ps.getTotalCount()得到总结果数 swLNNA.
ps.getStartIndex()当前分页索引 vrvi]
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ps.getNextIndex()下一页索引 X|R"8cJ
ps.getPreviousIndex()上一页索引 sLK$H|%>m
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 x
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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 Emk:@$3{r
HisH\z/i5)
一下代码重构了。 $5Rx>$~+d
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我把原本我的做法也提供出来供大家讨论吧: =:H EF;!
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首先,为了实现分页查询,我封装了一个Page类: b~TTz`HZ
java代码: aQj6XGu
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/*Created on 2005-4-14*/ S*WLb/R2
package org.flyware.util.page; "`*
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shVEAT'`
/** TR'_v[uK3
* @author Joa KJt6d`ZN
* ')(U<5y)
*/ $ao7pvU6
publicclass Page { ,lb}&uZo
>U]KPL[%
/** imply if the page has previous page */ _gl1Qtv@rf
privateboolean hasPrePage; |jcIn[)=
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/** imply if the page has next page */ 7(<r4{1?
privateboolean hasNextPage; d8p5a
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/** the number of every page */ ?&VKZSo
privateint everyPage; m'uFj !
-NA2+].
/** the total page number */ +Y>oNX1KN
privateint totalPage; h)z2#qfc
<%=<9~e
/** the number of current page */ |vxmgX)
privateint currentPage; r,P`$-
}!m}?
/** the begin index of the records by the current Fn{Pmo*rs
XS.*CB_m_
query */ 4Wa*Pcj
privateint beginIndex; sR)jZpmC(
D4~]:@v~n
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/** The default constructor */ @eq.&{&
public Page(){ _SU6Bd/>
9xFI%UOb#
} A-YW!BT4
8U!$()^?
/** construct the page by everyPage Q2*
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* @param everyPage #WAX&<m
* */ Af`Tr6)
public Page(int everyPage){ .-Dc%ap]
this.everyPage = everyPage; s3VD6xi7
} B|'}HBkP
K@a#^lmd
/** The whole constructor */ d;{k,rP6
public Page(boolean hasPrePage, boolean hasNextPage, Fe.90)
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int everyPage, int totalPage, )RQQhB
int currentPage, int beginIndex){ js%n]$N
this.hasPrePage = hasPrePage; @3bVjQ`4f
this.hasNextPage = hasNextPage; n+nZ;GJ5d
this.everyPage = everyPage; (;-_j/
this.totalPage = totalPage; Qraa0]56
this.currentPage = currentPage; =r3g:j/>q
this.beginIndex = beginIndex; _/Ay$l;F
} ]EG8+K6
m)Wq*&,o
/** ):y^g:
* @return [ 6Sk>j
* Returns the beginIndex. \C4wWh-A
*/ @a,=ApS"
publicint getBeginIndex(){ 7nP{a"4_
return beginIndex; "<^n@=g'q
} p"j&s
c c/nzB
/** y,w_x,m
* @param beginIndex PWkSl
* The beginIndex to set. +@*>N;$
*/ 5u3KL
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publicvoid setBeginIndex(int beginIndex){ 9<3fH J?vq
this.beginIndex = beginIndex; s)KlKh
} F/3L^k]
=%s6QFR
/** < RtyW
* @return ]Tg@wMgI
* Returns the currentPage. o2q-x2uB
*/ W1Ye+vg/s
publicint getCurrentPage(){ 8=zREt<Se
return currentPage; bbDm6,
} 8si{|*;hL
WWo"De@
/** uZ'Z-!=CL
* @param currentPage TQ0ZBhd
* The currentPage to set. 7AWq3i{
*/ 4=;j.=>0X
publicvoid setCurrentPage(int currentPage){ Upcx@zJ
this.currentPage = currentPage; oN%zpz;OR
} .yFO]
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/** b?qV~Dgk`
* @return `AvK=]
* Returns the everyPage. t%0c$c
*/ )=MK&72r
publicint getEveryPage(){ \sfc!5G
return everyPage; hZ!kh3@:`
} #
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/** `%"x'B`mM
* @param everyPage tE <?L
* The everyPage to set. Q"GM3?
*/ 67Qu<9}<-
publicvoid setEveryPage(int everyPage){ |5X59!
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this.everyPage = everyPage; %e3E}m>
} e6
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/** dNF_T?E\
* @return z!18Jh
* Returns the hasNextPage. uOy/c 8`
*/ 'mTY56Yq
publicboolean getHasNextPage(){ 4VwMl)8ic
return hasNextPage; s S#/JLDx]
} );6f8H@G
r<Cr)%z!
/** yXv@yn
* @param hasNextPage CR%h$+dzy
* The hasNextPage to set. }Nwp{["}]L
*/ +zq"dj_
publicvoid setHasNextPage(boolean hasNextPage){ jm@M"b'{
this.hasNextPage = hasNextPage; !MOsP<2
} 3 H5
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/**
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* @return NA'45}fQ
* Returns the hasPrePage. fjl9*
*/ Az8ZA ~Op=
publicboolean getHasPrePage(){ RWo7_X O
return hasPrePage; !Ko>
} F kf4R5Y?
; '
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/** cfa1"u""e
* @param hasPrePage = >tkc/aa
* The hasPrePage to set. "J2q|@.
*/ [u2t1^#Ol
publicvoid setHasPrePage(boolean hasPrePage){ !K}W.yv,
this.hasPrePage = hasPrePage; .Y?]r6CC/
} ag47 $9(
g<M!]0OK
/** B@i%B+qCLv
* @return Returns the totalPage. K<`Z@f3'w
* qm:C1#<p
*/ 0H^*VUyW/
publicint getTotalPage(){ Ddg!1SF
return totalPage; ]H}2|~c
} PuGs%{$(h
r hucBm
/** q{f\_2[
* @param totalPage -)')PV_+
* The totalPage to set. "0#(<zb|
*/ 2gZp
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publicvoid setTotalPage(int totalPage){ at@tS>Dv
this.totalPage = totalPage; 0 D
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} k_wcol,W
S\:+5}
} -aok ]w
m
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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 _LC*_LT_
Q8m%mJz~]
个PageUtil,负责对Page对象进行构造: WH1" HO
java代码: (&/4wI^M
4}/gV)
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/*Created on 2005-4-14*/ tm=,x~
package org.flyware.util.page; NFEr ,n
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import org.apache.commons.logging.Log; pY
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import org.apache.commons.logging.LogFactory; 1@t.J>
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/** uZrp ^
* @author Joa 5=
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* Er
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*/ r/ g{j
publicclass PageUtil { (P-^ PNz&
v:/!OvLe
privatestaticfinal Log logger = LogFactory.getLog cRrJZ9
'ZMh<M[
(PageUtil.class); >(igVaZ>
ly*v|(S&
/** #vyf*jPr
* Use the origin page to create a new page P*
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* @param page j0{`7n
* @param totalRecords <zn)f@W
* @return -sJD:G,%
*/ -A
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publicstatic Page createPage(Page page, int 2 >O [Y1
^t
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totalRecords){ 1[Yl8W%pj
return createPage(page.getEveryPage(), ~=OJCKv5(
aXVldt'
page.getCurrentPage(), totalRecords); W9w(a:~hY
} e3CFW_p
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/** Y"8@\73(R
* the basic page utils not including exception hjg1By(
er3~gm
handler n8;L_43U
* @param everyPage Oz-/0;1n
* @param currentPage }a5TY("d9H
* @param totalRecords @~ke=w6&pe
* @return page xtv%C
*/ RNB&!NC
publicstatic Page createPage(int everyPage, int r7R'beiH
)yig=nn
currentPage, int totalRecords){ TM#L.xPMf
everyPage = getEveryPage(everyPage); T>nH=
currentPage = getCurrentPage(currentPage); 06AgY0\
int beginIndex = getBeginIndex(everyPage, PsNrCe%e
8h=m()Eu
currentPage); UwS7B~
int totalPage = getTotalPage(everyPage, 56s%Qlgx
5"57F88Y1
totalRecords); >fP;H}S6
boolean hasNextPage = hasNextPage(currentPage, m\jjj^f a
au50%sA~
totalPage); Xv!Gg6v6
boolean hasPrePage = hasPrePage(currentPage); X5.9~
^rq\kf*]
returnnew Page(hasPrePage, hasNextPage, l59\Lo:
everyPage, totalPage, zC)JOykI%
currentPage, @u/CNx,`X
B6IKD
beginIndex); aeN #<M&$<
} P/ 6$TgQ
$<)]~**K
privatestaticint getEveryPage(int everyPage){ Wu{_QuAB
return everyPage == 0 ? 10 : everyPage; 'q:7PkN!p
} 80Hi v
/Lr`Aka5
privatestaticint getCurrentPage(int currentPage){ Ow> u!P!
return currentPage == 0 ? 1 : currentPage; M.y!J
} s/hWhaS<
iupkb
privatestaticint getBeginIndex(int everyPage, int GNM>hQ)h:
)s:kQ~+
currentPage){ n;:.UGl9.
return(currentPage - 1) * everyPage; #lqH/>`>
} <h9nt4F
rAHP5dx:
privatestaticint getTotalPage(int everyPage, int P,m+^,
xva
e^gr
totalRecords){ 1o\2\B=k{
int totalPage = 0; =TEe:%mN
R2~y<^.V`Y
if(totalRecords % everyPage == 0) %>+lr%B
totalPage = totalRecords / everyPage; v4Ag~Evcx
else J/Y9 X,
totalPage = totalRecords / everyPage + 1 ; H?;+C/-K`_
)! rD&l$tE
return totalPage; u{=h%d/
} \,/ozfJ7dT
)?radg
privatestaticboolean hasPrePage(int currentPage){ +pT;;
9
return currentPage == 1 ? false : true; zP0<4E$M`
} =/a`X[9vI
l]&A5tz3
privatestaticboolean hasNextPage(int currentPage, yw+]S
~28{BY
int totalPage){ j}Svb1A
return currentPage == totalPage || totalPage == -a_qZ7
%KO8i)n
0 ? false : true; 1t/c@YUTy
} r0k:RJP
@Yb8CB
'=+N
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} ~2hzyEh
Y{e,I-"{
L T`T~|pz
rC|nE=i
UK^w;w2F
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。 4IW90"uc
|wb_im
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 YG*<jKcX
emJZ+:%
做法如下: T7ShE-X
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 R=Lkf
3C=QWw?
的信息,和一个结果集List: C<:wSS^@1
java代码: D6e?J.
$Nvox<d0
ho^c#>81
/*Created on 2005-6-13*/ ZI$P Qz2i
package com.adt.bo; I31Nu{
|I"&Z+m
import java.util.List; U%1M?vT/
{7IZN< e
import org.flyware.util.page.Page; ueW/i
w(+L&IBC
/** j4@6`[n:
* @author Joa h^IizrqU
*/ 4>Ht_B<<
publicclass Result { 4s>L]!
W$8
1GR|$E
private Page page; IYptNR
mrsN@(X0
private List content; [}Rs
j";L{
/** &BKnJ{,H
* The default constructor 2"
v{
*/ 2WKIO|'
public Result(){ qixnaiZ
super(); lnMU5[g{
} k+@ :+RL
+m}D.u*cp
/** -ImO y|
* The constructor using fields 5``usn/&Kj
* .Q</0*sp
* @param page gHL:XW^
* @param content 0Iyb}
*/ tnb'\}Vn
public Result(Page page, List content){ 8*VQw?{Uee
this.page = page; Ho%%voJBS
this.content = content; L)H/t6}i
} rP(;^8l"
|9m*?7
/** nGJ+.z
* @return Returns the content. L`w_Q2{sv
*/ dt=M#+g
publicList getContent(){ sA"B/C|(g
return content; (G>g0(;D-
} &xC5Mecb*
&$pQ Jf
/** T}'*Gry
* @return Returns the page. e/)Vx'd`+
*/ &6\E'bBt
public Page getPage(){ >\lBbqa#
return page; )5diX
+
k
} %NhZTmWm
a8y*Jz-E
/** ``h*A
* @param content .g_Kab3?L
* The content to set. <{HV|B7
*/ 0e'@Xo2e
public void setContent(List content){ 2) Q/cH\g
this.content = content; NdI~1kemr
} 0n?^I>j
]PH'G>x
/** qHYoQ.ke
* @param page CY@#_z
* The page to set. phcYQqR
*/ al]-*=v7}
publicvoid setPage(Page page){ Jj+Hj[(@
this.page = page; N<HJ}geC"
} j;&su=p"
} `jGG^w3
A9y3B^\*
Q,>]f@m
R6irL!akAd
b;G#MjQp'
2. 编写业务逻辑接口,并实现它(UserManager, MF5o\-&dN
y>JSo9[@
UserManagerImpl) }}d,xI
java代码: lM%3 ?~?Q&
14 hE<u
>yt8gw0J
/*Created on 2005-7-15*/ 6PRP&|.#
package com.adt.service; C.VU"= -
Zx%6pZ(.
import net.sf.hibernate.HibernateException; U;Q?Rh-W
EUuk%<q7C(
import org.flyware.util.page.Page; _VLA2#V>
/E5>cqX4A
import com.adt.bo.Result; m+dJ3
/,^AG2]( f
/** y-a3
* @author Joa yH',vC.
*/ .vtV2lq
publicinterface UserManager { %_ Vj'z~T
IFW"SfdZk
public Result listUser(Page page)throws
m}sh(W5\
![aa@nOSa
HibernateException; Y/,Cy0!
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} C.?~D*Q
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!,JV<(7k
uwWKsZ4:ij
V*F |Yo:
java代码: Na$[nv8qh
{1J4Q[N9m
G9r~O#=gy
/*Created on 2005-7-15*/ g,}_&+q:.M
package com.adt.service.impl; MW|:'D`
D[p`1$E-1v
import java.util.List; C?t!Uvs
%<^j=K= 0
import net.sf.hibernate.HibernateException; D`2w>{Y
CsiRM8
import org.flyware.util.page.Page; t`E e/L%
import org.flyware.util.page.PageUtil; `clp#l.ii
I@:"Qee
import com.adt.bo.Result; "g&hsp+i"A
import com.adt.dao.UserDAO; #=
@?)\~
import com.adt.exception.ObjectNotFoundException; E{{Kzr2$
import com.adt.service.UserManager; Jqz K5)
&ZI-#(P
/** "*ww>0[
* @author Joa -Rbv#Y
*/ Pd;G c@'~
publicclass UserManagerImpl implements UserManager { M&` b\la
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</*]
private UserDAO userDAO; #i=k-FA)H
[Lq9lw&
/** kt7x}F(?<
* @param userDAO The userDAO to set. )w,<XJhg`
*/ 3U%kf<m=
publicvoid setUserDAO(UserDAO userDAO){ 8QQh1q2
this.userDAO = userDAO; 0?O$->t
} D4$2'h
=TJ9Gr/R&:
/* (non-Javadoc) QVo>Uit
* @see com.adt.service.UserManager#listUser t:*1*;
1G)I|v9R
(org.flyware.util.page.Page) h}4yz96WD
*/ U;t1 K
public Result listUser(Page page)throws 8T88
VE?Aa
HibernateException, ObjectNotFoundException { $+$4W\-=X
int totalRecords = userDAO.getUserCount(); i@mS8%|l
if(totalRecords == 0) zZ;V9KM>v
throw new ObjectNotFoundException 17-B'Gl!<%
lcK4 Uq\q
("userNotExist"); k%VYAON
page = PageUtil.createPage(page, totalRecords); Z{x)v5yh2V
List users = userDAO.getUserByPage(page); Y=t?"E
returnnew Result(page, users); P=l 7m*m
} JJ9R,
8n6
hDXaCift
} n;wViw
j8c5_&
{.ypZ8JU
g'cVsO)S
Iw?*y.z|
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @km4qJZ
3)I]bui
询,接下来编写UserDAO的代码: A]ZQ?-L/
3. UserDAO 和 UserDAOImpl: n|Ts:>`V
java代码: H4W!Md
*W;;L_V"
0s79rJ
/*Created on 2005-7-15*/ r6GXmr
package com.adt.dao; xT(0-o*
X ]W)D
S
import java.util.List; ,4Q8r:_ u
@Ne&%F?^Z
import org.flyware.util.page.Page; bg|dV
Mdq|:^px
import net.sf.hibernate.HibernateException; 2qojU%fiH
T?RN} @D
/** $@O?
* @author Joa 'n=bQ"bQu
*/ -}PE(c1%?q
publicinterface UserDAO extends BaseDAO { MV2$0
%a|Qw(4\
publicList getUserByName(String name)throws TQb@szp:|
QUaV;6
4
HibernateException; V^4v`}Wgx
#!E`%'
s]
publicint getUserCount()throws HibernateException; 0U:X[2|)
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publicList getUserByPage(Page page)throws %?, 7!|Ls
+ K`.ck
HibernateException; \o=9WKc
w>8kBQ?b
} v*0J6<
v\CBw"
,|A6l?iV
a6cU<(WDeh
dQ~GE}[
java代码: $_;rqTk]g
Z,/^lg c,
,X1M!'
/*Created on 2005-7-15*/ Lq
;~6
package com.adt.dao.impl; xQU//kNL
UJQTArf
import java.util.List; (n8?+GCa
uD?RL~M
import org.flyware.util.page.Page; EpKZ.lCU
pdER#7Tq
import net.sf.hibernate.HibernateException; n#Dy
YVb
import net.sf.hibernate.Query; SXYwhID=
AZE%fOG<i
import com.adt.dao.UserDAO; 7w" !"W#
H ?9Bo!
/** !/tV}.*
* @author Joa -,YI>!
*/ .a :7|L#a
public class UserDAOImpl extends BaseDAOHibernateImpl ,/GFD[SQ
uL-kihV:-
implements UserDAO { N\&VJc
pfIK9>i
/* (non-Javadoc) <9"@<[[,
* @see com.adt.dao.UserDAO#getUserByName Lg(G&ljE@k
A^+k A)8
(java.lang.String) BTj1C
*/ "%+||IyW
publicList getUserByName(String name)throws D</?|;J#/
9S17Lr*c
HibernateException { [ ^\{>m7
String querySentence = "FROM user in class c(vi,U-hC
~,};FI
com.adt.po.User WHERE user.name=:name"; +PLJ
Query query = getSession().createQuery EXjR&"R
8YE4ln
(querySentence); zVtTv-DU
query.setParameter("name", name); *oIIcE4g7
return query.list(); m(:R (K(je
} c)N_"#&
"QS(4yw?jg
/* (non-Javadoc) *^7^g!=z2
* @see com.adt.dao.UserDAO#getUserCount() 7b-[# g
*/ }j1;0 kb?
publicint getUserCount()throws HibernateException { muF&t'k
int count = 0; z=>P jIW
String querySentence = "SELECT count(*) FROM +/%4E %
^t<L
user in class com.adt.po.User"; S/y(1.wh
Query query = getSession().createQuery n%;t Va
sA: /!9
(querySentence); rGt]YG#C
count = ((Integer)query.iterate().next X"g,QqDD
H&F2[ j$T
()).intValue(); Fd80T6[
return count; oz:J.<j24Z
} Vu~fF@
|
{[NQD3=+F
/* (non-Javadoc) yJqDB$0
* @see com.adt.dao.UserDAO#getUserByPage ;YQ6X>
Ue,eEer
(org.flyware.util.page.Page) L7(.dO0C
*/ d3T7$'l$
publicList getUserByPage(Page page)throws rc%*g3ryLG
s%>u[-9U
HibernateException { M_75bU
String querySentence = "FROM user in class C5Fq%y{$.
n],cs
com.adt.po.User"; 2%fkXH<
Query query = getSession().createQuery aG@GJ@w
ji ,`?
(querySentence); D,-L!P
query.setFirstResult(page.getBeginIndex()) CSm(yB{|pC
.setMaxResults(page.getEveryPage()); \WVY@eB
return query.list(); =&U7:u
} N9f;X{
Ahg6>7+R.
} kRz qgVr%
P'Jb')m
.7#04_aP
UZc{ Av
0j'k%R[l
至此,一个完整的分页程序完成。前台的只需要调用 C9T-4o1
gD6BPW~0
userManager.listUser(page)即可得到一个Page对象和结果集对象 a4!6K
-32.g\]
的综合体,而传入的参数page对象则可以由前台传入,如果用 @eDL j}
)#cGePA
webwork,甚至可以直接在配置文件中指定。 R&}{_1dj8
v{U1B
下面给出一个webwork调用示例: w{ x=e
java代码:
YwB\kN
t4iV[xl3F
RveMz$Yy
/*Created on 2005-6-17*/ 04z2gAo
package com.adt.action.user; B;L^!sLP
HR k^KB
import java.util.List; /#?i +z
\V<deMb=
import org.apache.commons.logging.Log; NslaG
import org.apache.commons.logging.LogFactory; \3z ^/F~
import org.flyware.util.page.Page; Hn(L0#Oqy
}*0*8~Q'5
import com.adt.bo.Result; Yr+ghl/ V
import com.adt.service.UserService; y
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import com.opensymphony.xwork.Action; z#|tl/aP9
( KG>lTdN
/** K fNR)
* @author Joa s^AZ)k~J(
*/ ?Wp{tB9N0
publicclass ListUser implementsAction{ noNL.%I
~7=w,+
privatestaticfinal Log logger = LogFactory.getLog Wv)2dD2I
We#O'm
(ListUser.class);
KY;E. D`
N+ R/ti
private UserService userService; 6~Xe$fP(
?x
&"EhA>
private Page page; @AkD-}^[
[PW*|U
privateList users; )c<5:c
;;- I<TL
/* 0bk094
* (non-Javadoc) axi%5:I
* }+f@$L
* @see com.opensymphony.xwork.Action#execute() re}P
*/ -{fbZk&A
publicString execute()throwsException{ $X;fz)u
Result result = userService.listUser(page); X<"W@
page = result.getPage(); %7rWebd-
users = result.getContent(); o%A@
OY
return SUCCESS; ;H8A"$%n~
} J;BG/VI1
e c`3Qw
/** Kth^WHL
* @return Returns the page. xlaBOK a%
*/ wXsA-H/`
public Page getPage(){ QFf lx
return page; dPRGL
hWF
} bKH8/*Yk
Jk7[}Jc$
/** '4qi^$|\
* @return Returns the users. ~?{@0,$
*/ dKyX70Zy9
publicList getUsers(){ e]{X62]
return users; aKC3T-
} b9([)8
2}Q)&;u
/** PRCr7f
* @param page {N$G|bm]u<
* The page to set. rm4j8~Ef
*/ Y&5h_3K;<
publicvoid setPage(Page page){ 8a1G0HRQ
this.page = page; S<LHNZu|^A
} 5X-cDY*|
'%RYo#
/** _dq.hW7
* @param users *(x`cf;k
* The users to set. d&0^AvM@
*/ ^@`dsll
publicvoid setUsers(List users){ HtIM8z#/
this.users = users; ~>ACMO
} RxkcQL/Le
c>r0N[
/** .)mw~ 3]
* @param userService 9oY%v7
* The userService to set. 3&-BO%i
*/ "Gxf[6B
publicvoid setUserService(UserService userService){ q $s0zqV5
this.userService = userService; U:xr['
} lG;sDR|)(
} nMXSpX>!|
[ua{qJ9
D{/GjFO
nQvv'%v0
%c(':vI#
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, f?_H02j`/E
nlK"2/W
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 NQ%lwE~
#2&_WM!
么只需要: %Ow,.+m
java代码: =8fp4#]7
,?7URx*
Ut8yA"Y~
<?xml version="1.0"?> t*^Q`V wQ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork +B%ZB9
`hL16S
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 5>JrTO5
dHzo_VV
1.0.dtd"> }S$]MY,*
!B(6
<xwork> m4|9p{E
A3 bE3Fk$
<package name="user" extends="webwork- !["WnF{5eC
2rf-pdOvG
interceptors"> D'#Wc#b
5+'1 :Sa(i
<!-- The default interceptor stack name Rg,pC.7;
_w=si?q
--> "wT[LA9\
<default-interceptor-ref ]Z@-r
' Ky5|4
name="myDefaultWebStack"/> W)?B{\
hO@'WoniW
<action name="listUser" X)xQKkL0
Y:/z)"u,C
class="com.adt.action.user.ListUser"> SV}I+O_w
<param W :jC2,s!m
WeE>4>^
name="page.everyPage">10</param> ,Rk;*MEMJ
<result c63DuHA*C
Y|g8xkI}XB
name="success">/user/user_list.jsp</result> '$PiyM|V
</action> Qhsh{muw(
Y:oL
</package> CbA!
: }v&TQ
</xwork> diGPTV-?$
ub6=^`>h
kc\^xq~
iu2{%S)w
[GX5jD#
4}Y2
B$
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 :e`;["(,
~%B^`s
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。 =M)+O%`*6
<l(LQmM;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 )}1J.>5
r%JJ5Al.S
hdp;/Qz&
S.aSNH<
34Q l7LQp[
我写的一个用于分页的类,用了泛型了,hoho KQj5o>} 6
*pCT34'--
java代码: J84Q|E
+HQX]t:Y
lO9ML-8C1
package com.intokr.util; 5\V>Sj(
f+j\,LJ
import java.util.List; &aqF||v%)
K 38e,O
/** )'KkO$^&
* 用于分页的类<br> \m~?mg"#
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 61HU_!A8S
* r1yz ?Y_P
* @version 0.01 M3c-/7
* @author cheng h.E8G^}@
*/ /\V-1 7-
public class Paginator<E> { (PE x<r1
privateint count = 0; // 总记录数 8hZ+[E}
privateint p = 1; // 页编号 SZW`|ajH
privateint num = 20; // 每页的记录数 8<z+hWX=4
privateList<E> results = null; // 结果 1~Zmc1]
'kf]l=i[n
/** E4GtJ`{X
* 结果总数 Cb5;l~}L
*/ {M96jjiInf
publicint getCount(){ /qa{*"2Qo
return count; YD_hg#=n
} lO! Yl:;m%
]*|+06
publicvoid setCount(int count){ (B{`In8G>y
this.count = count; \C $LjSS-
} oOlqlv
;fw}<M!6
/** lk]q\yO_%
* 本结果所在的页码,从1开始 Gjfb<
* /]zn8d
* @return Returns the pageNo. j\iE3:94$
*/ bfcQ(m5
publicint getP(){ +sq'\Tbp
return p; vg[A/$gLM
} Zvz Zs
Jw3VWc
]]
/** UKV0xl
* if(p<=0) p=1 Z:9xf:g*
* o{7wPwQ;*
* @param p
n@xC?D:t*
*/ Y S/x;
publicvoid setP(int p){ jD1/`g%
if(p <= 0) ;c p*]
p = 1; 'c7C*6;a
this.p = p; f1s3pr??
} U{/d dCf7
blO(Th&
/** "159Q
* 每页记录数量 wV8_O)[
*/ 3m%oXT
publicint getNum(){ j5\z7
return num; x7\b-EC
} 3,`I\>No
vZMb/}-o
/** ;Z^\$v9?
* if(num<1) num=1 N~H!6N W
*/ )E9[=4+*C$
publicvoid setNum(int num){ UMtnb:ek
if(num < 1)
ac
num = 1; 8J|2b; Vf
this.num = num; Nz/PAs7g6
} FM$$0}X
_y:-_q
/** y7pwYRY
* 获得总页数 #gW"k;7P
*/ [$\KS_,Mn
publicint getPageNum(){ DO*rVs3'p[
return(count - 1) / num + 1; %Q,6 sH#
} tofX.oi+C$
Sc b'
/** de7
\~$
* 获得本页的开始编号,为 (p-1)*num+1 2<$pai"yl
*/ E8X(AZ 2
publicint getStart(){ a]H&k$!c
return(p - 1) * num + 1; 5&)T[Q X`
} }2xgm9j<
2|`7_*\
/** i~Q nw-^B
* @return Returns the results. O>R@Xj)M
*/
RE._Ov>
publicList<E> getResults(){ |P_voht
return results; C b4.N8
} '=AqC,\#
?)NgODU
public void setResults(List<E> results){ z}BuR*WSY{
this.results = results; *.us IH2
} af@R\"N9c
G*s5GG@Z.
public String toString(){ `d c&B
StringBuilder buff = new StringBuilder hy&WG&qf
(N"9C+S}
(); o[I
s$j
buff.append("{"); Y{KN:|i.!
buff.append("count:").append(count); !w1acmo<_
buff.append(",p:").append(p); Xr."C(`w
buff.append(",nump:").append(num); `y3*\l
buff.append(",results:").append P(oGNKAS
Tuz~T
_M
(results); Y sDai<
buff.append("}"); x)R1aq
return buff.toString(); F4NMq&_
} o,rK8x
bV$g]->4e
} %)ri:Q q
g& ou[_A
aH7@:=B