Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 >!v,`O1
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 MF`k~)bDV
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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 "<n"A7e
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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 :]z-Rz
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分页支持类: .X=M!
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java代码: n+F-,=0
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package com.javaeye.common.util; !=Kay^J~.
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import java.util.List; 5SWX v+
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publicclass PaginationSupport { ]v,y(yl
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publicfinalstaticint PAGESIZE = 30; ~JmxW;|_x)
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privateint pageSize = PAGESIZE; O@(.ei*HJ!
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privateList items; ALt";8Oa
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privateint totalCount; .2 SIU4[P
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privateint[] indexes = newint[0]; zvs 2j"lb
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privateint startIndex = 0; @LMV ?
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public PaginationSupport(List items, int 9(evHR7
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totalCount){ /:L&uqA
setPageSize(PAGESIZE); Kmf-l*7}
setTotalCount(totalCount); WxP4{T* <
setItems(items); $6?KH7lA
setStartIndex(0); m4.V$U,H]
} /s0VyUV=
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public PaginationSupport(List items, int ;\&bvGj8V
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totalCount, int startIndex){ l aL4ez
setPageSize(PAGESIZE); :Y?08/V
setTotalCount(totalCount); =Q0)t_z_
setItems(items); m?CjYqvf
setStartIndex(startIndex); $MEbePxe
} {]m
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public PaginationSupport(List items, int ez9M]! 8Lt
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totalCount, int pageSize, int startIndex){ vlKKPS
setPageSize(pageSize); Z5^UF2`Q
setTotalCount(totalCount); |;1:$E"
setItems(items); l:C0:m%
setStartIndex(startIndex); }8KL]11b
} )Zr0_b"V:e
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publicList getItems(){ kK6>>lD'
return items; %_LHD|<
} ~,4Znuin
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publicvoid setItems(List items){ ba1QFzN
this.items = items; x,*t/nzR
} jM@I"JZb
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publicint getPageSize(){ !g:G{b
return pageSize; O6 J<Lqgh
} (c7{dYV
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publicvoid setPageSize(int pageSize){ [GT1,(}.
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this.pageSize = pageSize; p2?+[d
} zi 14]FWo
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publicint getTotalCount(){ 83(P_Y:
return totalCount; !8M'ms>s=
} 'WgwLE_
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publicvoid setTotalCount(int totalCount){ /9#jv]C:
if(totalCount > 0){ I:7,CV
this.totalCount = totalCount; -~aEqj#?
int count = totalCount / <NsT[r~C
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pageSize; KD*4n'm!>
if(totalCount % pageSize > 0) +~AI(h
count++; 'bO? =+c
indexes = newint[count]; 8LKZ3Y|
for(int i = 0; i < count; i++){ lLf01sa4
indexes = pageSize * )_ u'k /
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i; ^0~1/ PhOw
} Pz!yIj
}else{ zNs8\
this.totalCount = 0; |hyr(7
} _$lQK{@rY
} by[(9+/z$
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publicint[] getIndexes(){ wd0ACF
return indexes; WSwmX3rn
} Vjd
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publicvoid setIndexes(int[] indexes){ m$: a|'mS
this.indexes = indexes; ~q>ilnL"h
} ?P]md9$(+e
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publicint getStartIndex(){ }7v2GfEkM
return startIndex; Q{-r4n|b
} jX,~iZ_B
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publicvoid setStartIndex(int startIndex){ =h!m/f^x
if(totalCount <= 0) oOz6Er[KO
this.startIndex = 0; =Z$6+^L
elseif(startIndex >= totalCount) 5q>u
}J
this.startIndex = indexes zvj >KF|y
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[indexes.length - 1]; /q]@|5I
elseif(startIndex < 0) Or|LyQU
this.startIndex = 0; 9hzU@m
else{ (*gpa:Sc
this.startIndex = indexes L+CSF ]
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[startIndex / pageSize]; Pl6=._
} S>Y?QQ3#wp
} Ymvd=F
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publicint getNextIndex(){ s1q d/
int nextIndex = getStartIndex() + S22 ;g
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pageSize; i9"1
if(nextIndex >= totalCount) \_'pUp22
return getStartIndex(); 9-SXu lgu
else 8hT>)WH}wo
return nextIndex; ?H?r!MZ%
} oPir]`re
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publicint getPreviousIndex(){ K-5)Y+| >
int previousIndex = getStartIndex() - &x #5-O'
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pageSize; Y8(yOVy9
if(previousIndex < 0) 39CPFgi<l*
return0; nU)f]4q{Ec
else 0qd`Pf
return previousIndex; `^[ra%a
} yhmW-#+^e
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} x.RZ!V-
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抽象业务类 v\C+G[MV7
java代码: Mt`.|N;y!
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/** ;7hr8?M|
* Created on 2005-7-12 ?9"glzxr
*/ %h rR'*nG
package com.javaeye.common.business; }Of^Y@{q.
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import java.io.Serializable; -6\9B>qa
import java.util.List; k,,}N9
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import org.hibernate.Criteria; =Ju}{ bX
import org.hibernate.HibernateException; "mA/:8` Q
import org.hibernate.Session; _QY "#
import org.hibernate.criterion.DetachedCriteria; +W`~bX+
import org.hibernate.criterion.Projections;
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import Q@R8qc=*
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org.springframework.orm.hibernate3.HibernateCallback; J2rH<Fd[up
import c9@*
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org.springframework.orm.hibernate3.support.HibernateDaoS E
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upport; L<n_}ucA
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import com.javaeye.common.util.PaginationSupport; uJizR
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public abstract class AbstractManager extends 6822xk
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HibernateDaoSupport { sQw-#f7t
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privateboolean cacheQueries = false; Qi M>59[
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privateString queryCacheRegion; O?_'6T
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publicvoid setCacheQueries(boolean n~Ix8|S h
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cacheQueries){ #,sJd ^uI
this.cacheQueries = cacheQueries; EifYK
} jp|wc,]!
@Hzsud
publicvoid setQueryCacheRegion(String 'CvZiW[_r
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queryCacheRegion){ _B2t|uQ
this.queryCacheRegion = w jF\>
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queryCacheRegion; h!MT5B)r.
} kI]1J
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publicvoid save(finalObject entity){ BLRrHaX0
getHibernateTemplate().save(entity); !u"Hf7/
} Y+E@afsKs
r?$\`,;
publicvoid persist(finalObject entity){ &nq[Vy0kO4
getHibernateTemplate().save(entity); "F^EfpcJ{9
} kDrGl{U}
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publicvoid update(finalObject entity){ Ur@3_F
getHibernateTemplate().update(entity); F]&9Lp}
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} G} p~VLf
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publicvoid delete(finalObject entity){ pT
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getHibernateTemplate().delete(entity); <NUZPX29
} cWi2Sls
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publicObject load(finalClass entity, ],LOkAX
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finalSerializable id){ ^0 t`EZ$
return getHibernateTemplate().load m$kmoY/
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(entity, id); q+ .=f.+Z
} <rkF2 -K,
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publicObject get(finalClass entity, D^pAf/ek@i
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finalSerializable id){ T@L^RaPX
return getHibernateTemplate().get E'C[+iK6,
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(entity, id); ]2<g"zo0
} `f(!i mN
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publicList findAll(finalClass entity){ o,d:{tt
return getHibernateTemplate().find("from 90q*V%cS
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" + entity.getName()); *Q)+Y&qn
} \(u P{,ML
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publicList findByNamedQuery(finalString x@/!H<y
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namedQuery){ SXhJz=h
return getHibernateTemplate 3TJNlS
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().findByNamedQuery(namedQuery); cD 1p5U
} !({[^[!
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publicList findByNamedQuery(finalString query, 4)`{ L$
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finalObject parameter){ I?1^\s#L
return getHibernateTemplate % $J^dF_0
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().findByNamedQuery(query, parameter); {BF$N#7
} Dd*C?6
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publicList findByNamedQuery(finalString query, R_-.:n%.z
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finalObject[] parameters){ C 9DRVkjj
return getHibernateTemplate CkOd>Kn
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().findByNamedQuery(query, parameters); R8mL|Vb|
} H6L`239u
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publicList find(finalString query){ :/u
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return getHibernateTemplate().find #jnb6v=5v
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(query); gG#M-2P
} LEY$St
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publicList find(finalString query, finalObject Er{yQIi0L
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parameter){ oR5 'g7?
return getHibernateTemplate().find #zfBNkk &@
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(query, parameter); W &*0F~
} gg<lWeS/3
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public PaginationSupport findPageByCriteria fi1tF/`
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(final DetachedCriteria detachedCriteria){ 0;)4.*t
return findPageByCriteria 1;>J9
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); d^w6_
} "wdC/
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public PaginationSupport findPageByCriteria ]c*&5c$
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(final DetachedCriteria detachedCriteria, finalint =ove#3
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startIndex){ KZ&{Ya
return findPageByCriteria SDZ/rC!C
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(detachedCriteria, PaginationSupport.PAGESIZE, WxFVbtw
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startIndex); mkgDg y
} <&B)i\j8=b
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public PaginationSupport findPageByCriteria Uh{|@D
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(final DetachedCriteria detachedCriteria, finalint "HlT-0F
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pageSize, WSUU_^.
finalint startIndex){ n%A)#AGGc
return(PaginationSupport) u`g|u:(r
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getHibernateTemplate().execute(new HibernateCallback(){ nzU^G)
publicObject doInHibernate "OkJPu2!W
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(Session session)throws HibernateException { dxsPX=\:
Criteria criteria = |%Pd*yZA
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detachedCriteria.getExecutableCriteria(session); "luMz;B
int totalCount = uvi+#4~G
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((Integer) criteria.setProjection(Projections.rowCount `StlG=TB8
b{_J%p
()).uniqueResult()).intValue(); 4 1q|R[js!
criteria.setProjection r761vtC#
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(null); bs/Vn'CE
List items = 8!sl) R
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criteria.setFirstResult(startIndex).setMaxResults M$
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(pageSize).list(); yCpU173V
PaginationSupport ps = wX[g\,?}'
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new PaginationSupport(items, totalCount, pageSize, DJR_"8
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startIndex); >We4F2?
return ps; D5^wT>3>
} q-}qrg
}, true); 4J{6Wt";
} $9bLD
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public List findAllByCriteria(final /?VwoSgV^
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DetachedCriteria detachedCriteria){ vq=nG]cE)
return(List) getHibernateTemplate EZypqe):/C
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().execute(new HibernateCallback(){ 54r/s#|-3
publicObject doInHibernate q8#zv_>K
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(Session session)throws HibernateException { Yv>kToa\^
Criteria criteria = OO#_0qK
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detachedCriteria.getExecutableCriteria(session); SJ8Ax_9{q
return criteria.list(); ~Z-o2+xA
} C%H{"
}, true); )B)ecJJ_
} X;'H@GU0
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public int getCountByCriteria(final OXp(rJ*bK
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DetachedCriteria detachedCriteria){ 9X/]O<i,Es
Integer count = (Integer) Kjzo>fIC{
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getHibernateTemplate().execute(new HibernateCallback(){ UB^OMB-W.m
publicObject doInHibernate K,j'!VQA4g
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(Session session)throws HibernateException { y!eT>4Oyg
Criteria criteria = ;8m) a
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detachedCriteria.getExecutableCriteria(session); %[B^b)2
return 7bSj[kuN
As{ "B
criteria.setProjection(Projections.rowCount
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> zA*W<g
()).uniqueResult(); mUA!GzJ~u-
} SR_<3WW
}, true); N(s5YX7<hd
return count.intValue(); wAD%1;
} l$Y*ii
} pT|l "q@
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用户在web层构造查询条件detachedCriteria,和可选的 R`KlG/Tk
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 L0.F}~S
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PaginationSupport的实例ps。 T_)G 5a
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ps.getItems()得到已分页好的结果集 -kzp>=
ps.getIndexes()得到分页索引的数组 }i._&x`):
ps.getTotalCount()得到总结果数 _$+BYK@
ps.getStartIndex()当前分页索引 gx9=L&=d
ps.getNextIndex()下一页索引 g286
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ps.getPreviousIndex()上一页索引 `:.a5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 o3W@)|>
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 l=UXikx
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一下代码重构了。 nD.K*# u
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我把原本我的做法也提供出来供大家讨论吧: = IJ}b=:
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首先,为了实现分页查询,我封装了一个Page类: gz#2}
java代码: AZ>F+@ d
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/*Created on 2005-4-14*/ nT
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package org.flyware.util.page; K2{6{X=
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/** ?U+nR/H:6
* @author Joa DGbEQiX$\
* _9yW; i-
*/ 2q4-9vu
publicclass Page { >N~orSw%
ZZM;%i-B
/** imply if the page has previous page */ +;T\:'CU
privateboolean hasPrePage; j-#h^3l1?
BD-
c<K"
/** imply if the page has next page */ Dy&{PeE!
privateboolean hasNextPage; 5[LDG/{Tys
/Z~5bb(
/** the number of every page */ LNcoTdv}k
privateint everyPage; =%SH2kb
+,]_TxL|C
/** the total page number */ 0YZ66VN!
privateint totalPage; <ivq}(%72
v]\T&w%9
/** the number of current page */ ioBYxbY`
privateint currentPage; ^+w1:C 5
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/** the begin index of the records by the current l}@C'Np
!Qq~lAJO;
query */ Lb#PiTJI
privateint beginIndex; -HF1c
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/** The default constructor */ cJ\1ndBH
public Page(){ vRb7=fXf
lWDSF]ZYV
} [Lcy &+
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/** construct the page by everyPage (&-I-#i
* @param everyPage eus@;l*
* */ K5 EJ#1ov
public Page(int everyPage){ z+KZ6h
this.everyPage = everyPage; G<P/COI#M5
} [0D.+("EW
q'9;
/** The whole constructor */ YJ+l
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public Page(boolean hasPrePage, boolean hasNextPage, 7+Er}y>
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int everyPage, int totalPage, h.\p+Qw.
int currentPage, int beginIndex){ a4XK.[O
this.hasPrePage = hasPrePage; MoXai0d%
this.hasNextPage = hasNextPage; jX.'G
this.everyPage = everyPage; YZAQt*x
this.totalPage = totalPage; +TAyCxfmt
this.currentPage = currentPage; ]c1#_MW
this.beginIndex = beginIndex; kzVK%[/
} &oE'|^G
{113B)
/** ;{Yr|
* @return /.(~=6o5
* Returns the beginIndex. !$/P8T``M
*/ 7pN&fAtj/
publicint getBeginIndex(){ n\< uT1n
return beginIndex; dXPTW;w
} e5D\m g)
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/** _q4Yq'dI
* @param beginIndex Fr-Vq=j&
* The beginIndex to set. k(xB%>ns
*/ %XQJ!sC`
publicvoid setBeginIndex(int beginIndex){ ZFtJoGaR
this.beginIndex = beginIndex; >U.7>K
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} {N
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/** H6Ytp^~>
* @return _0y]U];ce
* Returns the currentPage. OKAmw>{
*/ WHqw=!G
publicint getCurrentPage(){ ps^["3e
return currentPage; *uSlp_;kB
} ZENblh8fs
+Ht(_+To1
/** _;R#B`9Iu
* @param currentPage ~>Y^?l
* The currentPage to set. Q3'P<"u
*/ q;#bFPh
publicvoid setCurrentPage(int currentPage){ -v:3#9uX)
this.currentPage = currentPage; ,kUg"\_k
} ,4k3C#!.i
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/** y4VO\N!
* @return VtMnLFMw
* Returns the everyPage. $
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*/ 7q:;3;"9
publicint getEveryPage(){ >}/T&S
return everyPage; ?BbEQr
} GP x+]Jw8\
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/** >|0I\{C
* @param everyPage 1ed^{Wa4$9
* The everyPage to set. {suQ"iv
*/ }rnu:7
publicvoid setEveryPage(int everyPage){ HdyE`FY \
this.everyPage = everyPage; C~^T=IP
} 2Ima15^+F
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/** JE# H&]
* @return =@&>r5W1
* Returns the hasNextPage. s@g _F
*/ p} JGx^X~
publicboolean getHasNextPage(){ o?+?@Xb'
return hasNextPage; DHbS=Iih
} n<F3&2w
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/** E>:#{%
* @param hasNextPage 'e6J&X
* The hasNextPage to set. WEoD?GLS8
*/ VA`VDUG,
publicvoid setHasNextPage(boolean hasNextPage){ PP/#Z~.M
this.hasNextPage = hasNextPage; $GOF'
} @1qdnU
].Ra=^q
/** .krEfY&
* @return LoOw]@>
* Returns the hasPrePage. z@~mu
*/ 99%R/m
publicboolean getHasPrePage(){ 2IP<6l8N
return hasPrePage; =$ T[
} />uE)R$
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/** %s ;5
* @param hasPrePage s2F[v:|Wq
* The hasPrePage to set. /XNC^!z6Js
*/ -S&d5(R
publicvoid setHasPrePage(boolean hasPrePage){ Zqv
this.hasPrePage = hasPrePage; yTNHM_P
} IsVR4t]
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/** -FrK'!\
* @return Returns the totalPage. sxdDI?W4
* ma/<#l^}
*/ r=xec@R]*
publicint getTotalPage(){ ys:F
return totalPage; )`2ncb
} -
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5=Bm;
/** |oQhtk8.
* @param totalPage m 0Uu2Z4
* The totalPage to set. p^Z|$aZZ
*/ [.$/o}
publicvoid setTotalPage(int totalPage){ p9!jM\(
this.totalPage = totalPage; ')iyD5/4
} ?;Da%VS3
@RCZ![XYWg
} l[<o t9P[
l*Fp}d.
rT[b ^l}
=B`=f,,#3
P057]cAat<
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 uLfk>&hc
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个PageUtil,负责对Page对象进行构造: K;`W4:,
java代码: -zZb]8\E
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/*Created on 2005-4-14*/ Zeq^dV5y77
package org.flyware.util.page; \Hq=_}]F
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import org.apache.commons.logging.Log; p
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import org.apache.commons.logging.LogFactory;
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w}M)]kY
/** K.}jyhKIKi
* @author Joa 4tvZJS
hV
* :c(I-xif
*/ dsK*YY jH
publicclass PageUtil { ]4'V59\
q4vHsy36
privatestaticfinal Log logger = LogFactory.getLog '$4&q629d
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(PageUtil.class); @Y ?p-&
5kHU'D
/** VkId6k:>6C
* Use the origin page to create a new page M"Z/E>ne
* @param page g>a%
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* @param totalRecords _UbyhBl
* @return DweF8c
*/ UnyJD%a
publicstatic Page createPage(Page page, int TXbi>t:/S{
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totalRecords){ T?1e&H%USV
return createPage(page.getEveryPage(), ?xwZ< A
c'Q.2^w^
page.getCurrentPage(), totalRecords); YWDd[\4
} l{\k\Q !4
<!*O[0s
/** ;0Ih:YY6
* the basic page utils not including exception Shss};QZf(
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handler `:dGPBBO
* @param everyPage }{[p<pU$C
* @param currentPage ++!0r['+>
* @param totalRecords sD6vHX%
* @return page MB6lKLy6~
*/ nFefDdP
publicstatic Page createPage(int everyPage, int ,8DjQz0ZPo
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currentPage, int totalRecords){ 20M]gw]
everyPage = getEveryPage(everyPage); cA{,2CYc
currentPage = getCurrentPage(currentPage); \}gITc).j
int beginIndex = getBeginIndex(everyPage, N0YJ'.=8,
awLSY:JI
currentPage); " "CNw-^t
int totalPage = getTotalPage(everyPage, u~Y+YzCxV
Lf;Uv[^c
totalRecords); Xa$tW%)
boolean hasNextPage = hasNextPage(currentPage, Pb7-pu5X
oP:OurX8V
totalPage); J$(79gH{
boolean hasPrePage = hasPrePage(currentPage); +('=RyoT
J|8 u
returnnew Page(hasPrePage, hasNextPage, g{hbq[>X]
everyPage, totalPage, D&6.> wt
.
currentPage, "&\]1A}Z-x
{!pYQ|#
beginIndex); y)7;"3Q<
} = d !YM6G
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privatestaticint getEveryPage(int everyPage){ xfqU
atC
return everyPage == 0 ? 10 : everyPage; NH,4>mV$!
} %D ,(S-Uj
!!])~+4pP
privatestaticint getCurrentPage(int currentPage){ d81[hT}q
return currentPage == 0 ? 1 : currentPage; h3p~\%^
} 8>:u%+C1c
W)`H(J
privatestaticint getBeginIndex(int everyPage, int jVSU]LU E
V)mi1H|m
currentPage){ T
0?9F2
return(currentPage - 1) * everyPage; ZRUI';5x
} Pj7MR/AH
D)eRk0iC
privatestaticint getTotalPage(int everyPage, int #
tU@\H5kN
~tB9kLFG
totalRecords){ %kk~qvW
int totalPage = 0; TEbE-h0)]
hNF, sA
if(totalRecords % everyPage == 0) nwJc%0
totalPage = totalRecords / everyPage; ?Lr:>
else Lnl-han%
totalPage = totalRecords / everyPage + 1 ; {HP.HK
G+NTn\
return totalPage; fBPJ8VY
} 92^Dn`g
3e|,Z'4}4
privatestaticboolean hasPrePage(int currentPage){ {InW%qSn_
return currentPage == 1 ? false : true; {<2q
} l,
-q:8
NOtwgZ-
privatestaticboolean hasNextPage(int currentPage, Y_nlIcu
(=tu~ ^
int totalPage){ 8qs8QK
return currentPage == totalPage || totalPage == A$]#f
Hnbd<?y
0 ? false : true; 21~~ =+)X
} .1[pO_
U5j0i]
N0(($8G
} q/3co86c
7zu3o
O9:J
^g
"IoY$!Hk
p5bM/{DP;K
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。 zi,":KDz#
qjIcRue'"
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 ^ANz=`N5,
mz^[C7(q'(
做法如下: Q0TKM>
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 vpu
NqN9
的信息,和一个结果集List:
83:qIfF
java代码: \3cg\Q+~
OLDEB.@
=5M
'+>
/*Created on 2005-6-13*/ Q8bn|#`
package com.adt.bo; 6hqqZ
Y67i\U>?
import java.util.List; %* @hS`
&0J/V>k
import org.flyware.util.page.Page; 6X$iTJ[\x
fq0[7Yb
/** \V9);KAOj
* @author Joa lziC.Dpa
*/ Mm#=d?YUHJ
publicclass Result { .%mjE'
i-&"1D[&
private Page page; /S%!{;:
|r53>,oR<:
private List content; v0|"[qGb
"z|%V/2b3
/** b/eo]Id ]
* The default constructor avH3{V
*/ t($z+C<
public Result(){ Ji:0J},m
super(); }/Y)^
} 8?k.4{?
B4;P)\2
/** 8j!(*'J.
* The constructor using fields p9iCrqi
* _ 4+=S)$
* @param page ] Oe[;<I
* @param content m{0u+obi&w
*/ "yxBD
7
public Result(Page page, List content){ e
irRAU
this.page = page; n/GJ&qLi:g
this.content = content;
%Lgfi
} vX}mwK8
`jCq`-.
/** )1]LoEdm`
* @return Returns the content. wGA%h.[M|
*/ $a+)v#?,
publicList getContent(){ =v/x&,Uj@6
return content; M.}QXta
} {X>U`0P
F6#U31Q=
/** v7-
d+P=
* @return Returns the page. @EcY&mP)
*/ c)=UX_S!
public Page getPage(){ [KwwhI@3
return page; [0hZg
} 7$I *ju_
DX#F]8bWl
/** %q,^A+=
* @param content BcD%`vGJ
* The content to set. e\>g@xE%
*/ 2E}^'o
public void setContent(List content){ VEg/x z4c
this.content = content; +l_$}UN
} ,=p.Cx'PR
vW4N[ .+
/** \Rvsy;7
* @param page 8rsv8OO
* The page to set. j<*`?V^
*/ nzORG
publicvoid setPage(Page page){ ecy41y'~:
this.page = page; y2Z1B2E%f
} vR"<:r47?
} "n=Ih_J
q CB9z
)d-{#
-2Azpeh
uDi#a~m@
2. 编写业务逻辑接口,并实现它(UserManager, YJ^TO\4WM
@Ao E>
UserManagerImpl) |qsY0zx
java代码: o] 7U;W
R!LKGiN
ss>?fyA
/*Created on 2005-7-15*/ uP[:P?,t
package com.adt.service; XD\Z$\UJE
CDM==Xa*
import net.sf.hibernate.HibernateException; \M`fkR,,'
@3b|jJyf
import org.flyware.util.page.Page; 7oI^sh k
F
/:2+
import com.adt.bo.Result; BV
HO_
2nPU $\du
/** h/%Hk;|9
* @author Joa \4`2k
*/ ; i><03
publicinterface UserManager { emI]'{_G
7eg//mL"6
public Result listUser(Page page)throws L&nGjC+Lr
zdUi1 b
HibernateException; W=~H_L?/
[0G>=h@u
} +2ih!$T;7>
oFRb+H(E
+iPS=?S
4x:Odt5
BO p&s>hI
java代码: LvNk:99:<
8Cr?0Z
q}["Nww-
/*Created on 2005-7-15*/ 4n@,
p0
package com.adt.service.impl; ZWJFd(6
(7rG~d1iS
import java.util.List; lFY;O !Y5\
1`_i%R^
import net.sf.hibernate.HibernateException; c};Qr@vpo
=>CrZ23B"
import org.flyware.util.page.Page; 1dK^[;v>3
import org.flyware.util.page.PageUtil; /vB%gqJvX
gU}?Yy
import com.adt.bo.Result; 7M1*SC
import com.adt.dao.UserDAO; U)p P^:|
import com.adt.exception.ObjectNotFoundException; ?Y~>H2
import com.adt.service.UserManager; rkl/5z??
|7I.DBjR;
/** A4?_0:<
* @author Joa -3r&O:
*/ JPk3T.qp
publicclass UserManagerImpl implements UserManager { C6eo n4Ut
LV 94i
private UserDAO userDAO; !m1pL0
)N2yhdcqI
/** E}qeh"sJt
* @param userDAO The userDAO to set. pz^"~0o5
*/ mHox
publicvoid setUserDAO(UserDAO userDAO){ d}',Bl+u{$
this.userDAO = userDAO; *#;rp~
} um&e.V)N
B%9[
/* (non-Javadoc) :OBggb#?!
* @see com.adt.service.UserManager#listUser w|PZSOJ
xZmKKKd0*
(org.flyware.util.page.Page) /BVNJNhz
*/ [:!#F7O-
public Result listUser(Page page)throws Bd"7F{H
FO}4~_W{
HibernateException, ObjectNotFoundException { D@Fa~O$75
int totalRecords = userDAO.getUserCount(); k 9Kv
if(totalRecords == 0) *.EtdcRo[
throw new ObjectNotFoundException i\rI j0+
%2oLND}?z
("userNotExist"); h{ce+~X
page = PageUtil.createPage(page, totalRecords); H$ xSl1>E
List users = userDAO.getUserByPage(page); tO?*x/XC{
returnnew Result(page, users); cVn7jxf
} wR/i+,K
)11/BB\v
} BoIe<{X(9
7XWgY%G
uW[s?
{M E|7TS=
qr=U=oK
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 4[.-
a&!}
Z/uRz]Hi
询,接下来编写UserDAO的代码: S,S_BB<Y[b
3. UserDAO 和 UserDAOImpl: 7!JoP?!
java代码: 6aQ{EO-]'=
jO:<"l^+u
}+ #ag:M
/*Created on 2005-7-15*/ qm]ljut
package com.adt.dao; #>ci!4Gz=Z
"Jnq~7]
import java.util.List; ? *I9
W.:kE|a.g
import org.flyware.util.page.Page; %v~j10e
dt3Vy*zL
import net.sf.hibernate.HibernateException; 9i|6
0#*\o1r\p
/** '}4[m>/
* @author Joa W {dx\+
*/ Z{_'V+Q1
publicinterface UserDAO extends BaseDAO { 7@tr^JykO
^#^u90I
publicList getUserByName(String name)throws ;N"XW=F4e
S%xGXmZ
HibernateException; [TO:-8$.
3y 3
U`Mo
publicint getUserCount()throws HibernateException; 3+ i(fg_
Z/x<U.B
publicList getUserByPage(Page page)throws *bRH,u
o~>p=5t
HibernateException; 8@+YcN;->
"?qu(}|
} @1Zf&'/6
'T|.<u@~
XcfTE
m
l]v
*h0!
Rb#Z\e}e-
java代码: <U,T*Ql1x
s^KxAw_IV
|+`hSA
/*Created on 2005-7-15*/ g\*gHHa
package com.adt.dao.impl; P<4jY?.
R?&S]?H
import java.util.List; 6/#= dv
[Q 2t,tQx
import org.flyware.util.page.Page; q}\\p
GF/p|I D
import net.sf.hibernate.HibernateException; \v-> '
import net.sf.hibernate.Query; zRE7 w:
Z p__
import com.adt.dao.UserDAO; D *LZ_
E!Fy2h>[Z
/** 0|^x[dh
* @author Joa <
m9O0
*/ 1;:2 =8
public class UserDAOImpl extends BaseDAOHibernateImpl -ZyFUGd%
([9h.M6v
implements UserDAO { <RhKlCP
i*U\~CZjT
/* (non-Javadoc) VJR'B={h
* @see com.adt.dao.UserDAO#getUserByName s9 E:6
.ySesN: C~
(java.lang.String) Aoo'i
*/ WX\%FJ
publicList getUserByName(String name)throws )Y
*?VqZn
*V"cu
HibernateException { s~]nsqLt9p
String querySentence = "FROM user in class '}rDmt~
s*8hN*A/,
com.adt.po.User WHERE user.name=:name"; D 1hKjB&
Query query = getSession().createQuery 'Yd%Tb|*
Y\%}VD2k
(querySentence); G8;S`-D1a,
query.setParameter("name", name); /e7'5#v
return query.list(); /t9w%Y
} 4
^+hw;
ASYUKh,h
/* (non-Javadoc) vSnb>z1
* @see com.adt.dao.UserDAO#getUserCount() %cm5Z^B1"
*/ a<Ns C1
publicint getUserCount()throws HibernateException { FQ-(#[
int count = 0; ]nQ$:%HP
String querySentence = "SELECT count(*) FROM c~tSt.^WX
YwF6/JA0^
user in class com.adt.po.User"; =6W:O
Query query = getSession().createQuery Zgg 7pL)#c
!gk\h
(querySentence); l =_@<p
count = ((Integer)query.iterate().next ~.@fk}'R
<7jb4n<
()).intValue(); yav)mO~QU6
return count; c^6`"\X^g
} iZSSd{jO
XsG]-Cw
/* (non-Javadoc) Cir =(
* @see com.adt.dao.UserDAO#getUserByPage Ov<3?)ok
xLD6A5n,[
(org.flyware.util.page.Page) *xl7;s
*/ ROjjN W`W
publicList getUserByPage(Page page)throws 6Ss{+MF|v
}agl:~C
HibernateException { g-:)}8d6
String querySentence = "FROM user in class kK1qFe?]
{&<}*4D
com.adt.po.User"; qIqk@u
Query query = getSession().createQuery Y(:OfC?
O)5PUyC:H
(querySentence); 3w9
]@kU
query.setFirstResult(page.getBeginIndex()) M|v.5l#
.setMaxResults(page.getEveryPage()); ipzUF o<w
return query.list(); u:S@'z>
} XOeh![eMX
m+m6"yE#_
} \Zh)oUHd
__V]HcP;
^2AF:(E
3H%HJS
_5K_YhT
至此,一个完整的分页程序完成。前台的只需要调用 k,@J&
={b
]
userManager.listUser(page)即可得到一个Page对象和结果集对象 O\LW
8\M
=k*0O_
的综合体,而传入的参数page对象则可以由前台传入,如果用 &S3W/lQs
#PrV)en
webwork,甚至可以直接在配置文件中指定。 :1lE98=
XF7W'^
下面给出一个webwork调用示例: :HE]P)wz-
java代码: `;_tt_
f~q&.,I(
cV{ZDq
/*Created on 2005-6-17*/ `HM3YC
package com.adt.action.user; pNqf2CnnT
ft'iv
import java.util.List; VA%"IAl
Fkz
import org.apache.commons.logging.Log; B@;)$1-UT
import org.apache.commons.logging.LogFactory; YEQW:r_h.S
import org.flyware.util.page.Page; &CL|q+-
osd^SnL1/5
import com.adt.bo.Result; I1myu Z
import com.adt.service.UserService; _M&.kha
import com.opensymphony.xwork.Action; bg ,}J/
ii;WmE&
/** |tg?b&QR
* @author Joa {a3kn\6H0
*/ 8Wj=|Ow-q
publicclass ListUser implementsAction{ fMQ*2zGu95
Ke ?uE
privatestaticfinal Log logger = LogFactory.getLog ,OKM\N,
yo*iv+l
(ListUser.class); /,Rca1W
L,
{rMLM%
private UserService userService; H< ;Fb;b
*!'&:
private Page page; mU=6"A0
U
|\a:]SlH
privateList users; Xo@YTol
KCk?)Qv
/* S(J\<)b
* (non-Javadoc) mei_aN7zW
* RGO:p]t|
* @see com.opensymphony.xwork.Action#execute() |sFe:TX
*/ |nEVOy>'
publicString execute()throwsException{ s\W
Result result = userService.listUser(page); M?B(<j1Ri
page = result.getPage(); IMGqJc,7
users = result.getContent(); ~B&*7Q7
return SUCCESS; d# 3tQ*G/
} m IzBK]@^
%<?ciU
/** w`}9/s;$
* @return Returns the page. s1vrzze
*/ v\Y}(fD
public Page getPage(){ M_1Tx
return page; e_=pspnZ
} Z02s(y=k1
b.4Xn0-M
/** Tdwwtbe
* @return Returns the users. rh`.$/^
*/ Yg)V*%0n
publicList getUsers(){ B#aH\$_U
return users; h_~|O[5|)
} R*@[Pg*
jBv$^L
/** 2 1~7{#
* @param page b%;59^4AjD
* The page to set. JYd7@Msfc
*/ }[z<iij4
publicvoid setPage(Page page){ v1r_Z($
this.page = page; )_v\{N
} )@qup _M@
(a}
/** fcICFReyV
* @param users W3/ 7BW`
* The users to set. 5)yOw|Bd
*/ "Py Wo
publicvoid setUsers(List users){ @%<?GNS O
this.users = users; ]&:b<]K3
} nnE_OK!}T
FxfL+}?Q
/** `<J#l;y
* @param userService v
(ka,Dk3
* The userService to set. irsfJUr[V
*/ _;:rkC fj
publicvoid setUserService(UserService userService){ +%wWSZ<#
this.userService = userService; 7"q+"0G
} ~*!u
} g(<T u^F
k\pDJ7wF^
Mi}I0yhVm
5_)@B]~nM
3eTrtCe$
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, ESMG<vW&f
*J_iXu|
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 VD24X
poD\C;o"
么只需要: d9Z&qdxTKq
java代码: _(6`{PWY
]G0dS
Fh{j
'_qQrP#
<?xml version="1.0"?> %5h^`lp
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork #+"4&:my
85D^@{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- q[G/}
#%^\\|'z
1.0.dtd"> =4zNo3IvL+
B:-U`CHHQ
<xwork> ] *-;' *
mP pvZ
<package name="user" extends="webwork- @H\pipT_b
H#L#2M%
interceptors"> ~XUOW Y75
uxOJ3
<!-- The default interceptor stack name K 3Yw8t2J
yW\XNX
--> {/d4PI7)tK
<default-interceptor-ref {7?9jEj
&$qF4B*
name="myDefaultWebStack"/>
\Mb(6~nC
hCM8/Vvx6
<action name="listUser" a@#Q:O)4
M
XZq
class="com.adt.action.user.ListUser"> fxDj+Q1p
<param 8xF)_UV
Wp5]Uk
name="page.everyPage">10</param> P8wy*JvT
<result ptpW41t}^
|3{+6cg
name="success">/user/user_list.jsp</result> f.oP
</action> {l2N&
j z~[5m}J
</package> ;8P_av}C
o]Wz6L
</xwork> (kIz
'{[!j6wt\
y" ^yYO
Di*]ab
(0i'Nb"
n%/i:Whs
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ImIqD&a-h
w[(n>
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 {-@~Q.&}v
NZLXN
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Ly9Q}dL
2sKG(^=Z
.^i<xY
:l+_ja&o
z% V* K
我写的一个用于分页的类,用了泛型了,hoho DVI7]+=nV
}[ ].\G\G
java代码: !?nu?
g96T*T
:peqr!I+K
package com.intokr.util; pOm@b`S%
2;G98H
import java.util.List; P,i"&9 8
S%kS#U${|
/** McjS)4j&.
* 用于分页的类<br> ,"Tjpdf
* 可以用于传递查询的结果也可以用于传送查询的参数<br> y%4 Gp
* P5xI
* @version 0.01 ]pnYvXf>!
* @author cheng v~"Ef_`
*/ k6@b|
public class Paginator<E> { n)#Lh
7X"
privateint count = 0; // 总记录数 @\)fzubu
privateint p = 1; // 页编号 9e~WK720=
privateint num = 20; // 每页的记录数 Z_FNIM0f
privateList<E> results = null; // 结果 M>T[!*nTj
rvic%bsk
/** /D[dO6.
* 结果总数 2F1ZAl
*/ Y0@yD#,0~
publicint getCount(){ *Bs^NU.
return count; QY@u}&m%o
} LM:)j:gS6
d$K=c1
publicvoid setCount(int count){ I"1CgKYK^+
this.count = count; XA1f' Kk
} JA`H@qE
JSgpb?(
/** =}v ;1m
* 本结果所在的页码,从1开始 h*s`^W3
* :uo[&&c
* @return Returns the pageNo. EKuSnlTXba
*/ %[`a
publicint getP(){ 3_W{T@T
return p; K\P!a@>1
} ~:[!Uyp0b
^av6HFQ
/** :a.0hes
* if(p<=0) p=1 ?*H9-2W@
* @9 )}cg
* @param p ?,07;>&
*/ ]#zZWg
zv
publicvoid setP(int p){ ;i\C]*
if(p <= 0) )~V}oKk0t
p = 1; 5Z{_m;I.
this.p = p; 4T`&Sl
} B'}"AC"
+8AvTSgX%
/** \D?:J3H*]
* 每页记录数量 ~*}$>@f{[X
*/ #~k[ 6YR 0
publicint getNum(){ \iru7'S
return num; +`.,| |Mq
} Ox qguT,
x=]S.XI
/** l~J*' m2
* if(num<1) num=1 IU#x[P!
*/ #Fs|f3-@
publicvoid setNum(int num){ *N F$1
if(num < 1) 0xCz'mJ
num = 1; >w.'KR0L
this.num = num; `T"rG}c
} ]^K;goQv
*HE^1IEl
/** /0lC KU!=
* 获得总页数 S~)w\(r
*/ z/ 7$NxJH
publicint getPageNum(){ 3;_
n{&
return(count - 1) / num + 1; >A}0Ho
} LA4<#KP
;`(R7X
*3
/** [2
zt ^
* 获得本页的开始编号,为 (p-1)*num+1 8IGt4UF&?
*/ eLfvMPVo
publicint getStart(){ nt ,7u(
return(p - 1) * num + 1; *1^$.Q&
} cp6WMHLj
>72JV;W]
/** g97]Y1g
* @return Returns the results. r:&|vP
*/ i sW\MB]
publicList<E> getResults(){ sJZ!sznn
return results; @dgH50o[
} WVX`<
p[v#EyoC
public void setResults(List<E> results){ 9(, @aZ
this.results = results; U)D[]BVg
} -5bA
$
rmd;\)#*`
public String toString(){ @r;wobt
StringBuilder buff = new StringBuilder 0$HmY2
Men
2e1]}wlK
(); 27D!'S
buff.append("{"); _A+w#kiv>
buff.append("count:").append(count); W5pb;74|
buff.append(",p:").append(p); ^Q.,\TL01
buff.append(",nump:").append(num); {0v*xL_O^
buff.append(",results:").append qlsQ|/'D
O1P=#l iYX
(results); 7G93,dJ
buff.append("}"); aeP[+ I9
return buff.toString(); cpZc9;@IC
} S%mfs!E>
Ug%_@t/?
} Bv9kSu9'~
5[gh|I;D
!EBY@ Y1