Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Q-v[O4y~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 D;]%
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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 L|LTsRIq
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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 "> 3@<f>
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分页支持类: ` qTY
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java代码: w>uZ$/
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package com.javaeye.common.util; Ef.4.iDJrR
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import java.util.List; fP58$pwu
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publicclass PaginationSupport { Gq/6{eRo\
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publicfinalstaticint PAGESIZE = 30; ;L2bC3
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privateint pageSize = PAGESIZE; s~
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privateList items; )/"7$2Aoy
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privateint totalCount; tY=%@v'6?
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privateint[] indexes = newint[0]; ,rQ)TT
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privateint startIndex = 0; r%d11[z
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public PaginationSupport(List items, int .E#Sm?gK
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totalCount){ (JW?azU
setPageSize(PAGESIZE); N?0y<S ?!
setTotalCount(totalCount); C+XZDY(=Z
setItems(items); 4rG 7\
setStartIndex(0); 1m;*fs
} ~qxXou,J
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public PaginationSupport(List items, int aG_ON0g
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totalCount, int startIndex){ z \>X[yNpA
setPageSize(PAGESIZE); J"/z?!)IB
setTotalCount(totalCount); PMs_K"-K
setItems(items); #J724`
setStartIndex(startIndex); ^G&D4uZ
} ?K {1S
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public PaginationSupport(List items, int bs EpET
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totalCount, int pageSize, int startIndex){ ^!o}>ls['
setPageSize(pageSize); (M,VwwN
setTotalCount(totalCount); Ir"Q%>K0f
setItems(items); m\M+pjz
setStartIndex(startIndex); s}9tK(4v
} $'YKB8C
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publicList getItems(){ WwtE=od
return items; D"4&9"C U
} V9u\;5oL
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publicvoid setItems(List items){ c[_^bs>k
this.items = items; T% 13 '
} -MU.Hu
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publicint getPageSize(){ 7'i#!5
return pageSize; 6\fMzm
} P3tG#cJ
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publicvoid setPageSize(int pageSize){ fGf-fh;s
this.pageSize = pageSize; ;'QY<,p[e
} e ]o'i;I
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publicint getTotalCount(){ r>~d[,^$m4
return totalCount; o 7W Kh=
} 4:&qTY)H
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publicvoid setTotalCount(int totalCount){ RB7AI!'a?
if(totalCount > 0){ yISQYvSN
this.totalCount = totalCount; aT:AxYn8
int count = totalCount / kgapTv>q
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pageSize; w&yGYHg
if(totalCount % pageSize > 0) Ocwp]Mut&
count++; x2;i<
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indexes = newint[count]; '&:1?i)
for(int i = 0; i < count; i++){ (
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indexes = pageSize * 30 [#%_* o
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} HXfXb^~
}else{ $dh4T";
this.totalCount = 0; *Ht*)l?
} c|}K_~l_
} 0w(T^GhZ
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publicint[] getIndexes(){ KU|BT.o8
return indexes; n5+S"
} Va@6=U7c
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publicvoid setIndexes(int[] indexes){ VP%i1|XZJ
this.indexes = indexes; poQdI?ed,
} Fu4EEi
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publicint getStartIndex(){ Cb{A:\>Q{
return startIndex; q)V1{B@
} %U5P}
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publicvoid setStartIndex(int startIndex){ %x}&=zx0*1
if(totalCount <= 0) Y62u%':X
this.startIndex = 0; wY3|#P
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elseif(startIndex >= totalCount) y=9Dxst"V
this.startIndex = indexes p2x1xv
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[indexes.length - 1]; (7;J"2M
elseif(startIndex < 0) q11QAx4p
this.startIndex = 0; uKbHFF
else{ b
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this.startIndex = indexes j&dx[4|m:h
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[startIndex / pageSize]; &{zwM |Q@?
} &IRA=nJ
} +[whh
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publicint getNextIndex(){ *5y
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int nextIndex = getStartIndex() + n{64g+
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pageSize; GG_^K#*
if(nextIndex >= totalCount) XLZ j
return getStartIndex(); B:?#l=FL
else df4sOqU
return nextIndex; U=F-]lD
} CZJHE>
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publicint getPreviousIndex(){ |^Ew<
int previousIndex = getStartIndex() - }PI35i1!t
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pageSize; \5'O.*pr
if(previousIndex < 0) `RL,ZoYuu
return0; 8
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else @ /UOSU
return previousIndex; h4aygc
} `6Ureui2?
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} N7*CP|?E
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抽象业务类 hNgpp-
java代码: [,O`MU
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/** bQwdgc),s{
* Created on 2005-7-12 L$1K7<i.
*/ T-9k<,>?
package com.javaeye.common.business; |N:MZ#};
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import java.io.Serializable; PwW^y#96
import java.util.List; T?X^0UdJj
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import org.hibernate.Criteria; >`7OcjLg
import org.hibernate.HibernateException; pi`;I*f/
import org.hibernate.Session; ~`t%M?l
import org.hibernate.criterion.DetachedCriteria; qyg*n>nt
import org.hibernate.criterion.Projections; -3.UE^W2
import 61/)l0<;
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org.springframework.orm.hibernate3.HibernateCallback; h?0F-6z
import g1ZV&X=2
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org.springframework.orm.hibernate3.support.HibernateDaoS Z-(} l2\
b fp,zs
upport; \ Y*h
})@tA<+
import com.javaeye.common.util.PaginationSupport; n{dP@_>WS
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public abstract class AbstractManager extends 8f?rEI\0GD
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HibernateDaoSupport { GAv)QZyV$
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privateboolean cacheQueries = false; 0iYP
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privateString queryCacheRegion; b.#^sm//
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publicvoid setCacheQueries(boolean J?Ck4dQ
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cacheQueries){ EdEoXY-2
this.cacheQueries = cacheQueries; q*L
]
} [%)@|^hw91
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publicvoid setQueryCacheRegion(String &yE1U#J(
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queryCacheRegion){ {3hqp*xl
this.queryCacheRegion = %a5t15 9
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queryCacheRegion; Oe/6.h?
} %X;7--S%?g
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publicvoid save(finalObject entity){ oEJaH
getHibernateTemplate().save(entity); *p=fi
} RI-A"cc6A
}2lO _i}L
publicvoid persist(finalObject entity){ D!oZ?dGCo6
getHibernateTemplate().save(entity); i;c'P}[K
} )s7bJjT0=X
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publicvoid update(finalObject entity){ %`#G92Z_
getHibernateTemplate().update(entity); tM)Iir*U#
} QU.0Elw
OB~C} '^$
publicvoid delete(finalObject entity){ M;*$gV<x
getHibernateTemplate().delete(entity); GuT6K}~|D
} X~lZ OVmS
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publicObject load(finalClass entity, !\^jt%e&
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finalSerializable id){ 9 ~~qAoD
return getHibernateTemplate().load }|Uj"e
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(entity, id); Z==!C=SBv
} GM](=|F
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publicObject get(finalClass entity, 1Ao6y.S
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finalSerializable id){ )GVBE%!WEd
return getHibernateTemplate().get uFZ~
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(entity, id); IZ*}idlkn/
} 'w(y
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publicList findAll(finalClass entity){ JWWYVl VC
return getHibernateTemplate().find("from f])M04<
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" + entity.getName()); f ba&`
} T"?Y5t`(
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publicList findByNamedQuery(finalString icE|.[
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namedQuery){ Ry z?v<)h
return getHibernateTemplate +3;Ody"59
%ISq>A)%
().findByNamedQuery(namedQuery); } B0sC%cm
} rfs (#
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publicList findByNamedQuery(finalString query, bKMWWJf*'
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finalObject parameter){ o'Wz*oY))\
return getHibernateTemplate 5;mRGY
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().findByNamedQuery(query, parameter); i5"5&r7r
} BFWi(58q
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publicList findByNamedQuery(finalString query, r?p[3JJ;mG
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finalObject[] parameters){ _({@B`N}
return getHibernateTemplate $W&:(&
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().findByNamedQuery(query, parameters); vT c7an6fy
} YLOwQj'
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publicList find(finalString query){ 4(=kE>n}
return getHibernateTemplate().find oQT2S>cm^
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(query); "_< 9PM1t
} 8[zb{PRu
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publicList find(finalString query, finalObject M-J<n>hl
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parameter){ ZyI$M 3{J
return getHibernateTemplate().find F2;:vTA>
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(query, parameter); |0sPka/u16
} #G#g|x*V
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public PaginationSupport findPageByCriteria l%~lz[
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(final DetachedCriteria detachedCriteria){ sI,W%I':d
return findPageByCriteria Vr=OYI'A
+
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 19c@ `?
} 2&he($HIzg
c2 A ps
public PaginationSupport findPageByCriteria ^m!_2_q
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(final DetachedCriteria detachedCriteria, finalint !_~Uv xM+
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startIndex){ =']3(6*
return findPageByCriteria V`#.7uUP
C\}/"
(detachedCriteria, PaginationSupport.PAGESIZE, lpgd#vr
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startIndex); 8(f:U@BS
} C ^w)|2o}
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public PaginationSupport findPageByCriteria 8Pmdk1 ~
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(final DetachedCriteria detachedCriteria, finalint 4)kG-[#
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pageSize, ]<XR]FHx)
finalint startIndex){ n~.*1. P
return(PaginationSupport) v2)g 1sXd
< zOi4v0
getHibernateTemplate().execute(new HibernateCallback(){ &nj&:?w
publicObject doInHibernate "m$3)7 $
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(Session session)throws HibernateException { /<Ld'J
Criteria criteria = i47j lyH
,"\@fwy{
detachedCriteria.getExecutableCriteria(session); lv%9MW0
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int totalCount = D`yEwpV^
s?rBE.g@}
((Integer) criteria.setProjection(Projections.rowCount mr:CuqJ
y_p.Gzy(^}
()).uniqueResult()).intValue(); IH9.F
criteria.setProjection lg$zGa?
zMi; A6
(null); o}$1Ay*q`
List items = "=1;0uy]
;*2>ES
criteria.setFirstResult(startIndex).setMaxResults @7oL#-
l Dxc`S
(pageSize).list(); mGjN_
PaginationSupport ps = IkPN?N
?6^|ZtB
new PaginationSupport(items, totalCount, pageSize, 7zemr>sIh
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startIndex); UUc8*yU)
return ps; ?jx1R^
} p-GAe,2q
}, true); T;5r{{
} )%d*3\Tsd
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public List findAllByCriteria(final CW&.NT
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DetachedCriteria detachedCriteria){ 47K1$3P
return(List) getHibernateTemplate tDg}Ys=4K>
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().execute(new HibernateCallback(){ l{j~Q^U})
publicObject doInHibernate V)(R]BK{
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(Session session)throws HibernateException { 'cix`l|^
Criteria criteria = sEJC-$
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detachedCriteria.getExecutableCriteria(session); @#g<IBG=*
return criteria.list(); v59dh (:`Z
} @.Icz
}, true); TS2ZF{m
} Uu 8,@W+
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public int getCountByCriteria(final 4d b(<h
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DetachedCriteria detachedCriteria){ ~Wo)?q8UY,
Integer count = (Integer) Y_woKc*
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getHibernateTemplate().execute(new HibernateCallback(){ !8NC# s
publicObject doInHibernate G 0%6ch^%
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(Session session)throws HibernateException { *37uy_EpV
Criteria criteria = %h?x!,q
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detachedCriteria.getExecutableCriteria(session); x^4xq#Bb7
return Qx;\USv
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criteria.setProjection(Projections.rowCount 0Z[oKXm1p
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()).uniqueResult(); [I!6PGx
} -K9c@?
}, true); p$Ox'A4
return count.intValue(); ojyIQk+
} S"wR%\NIp
} 7(5xL T$
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用户在web层构造查询条件detachedCriteria,和可选的 'Vyt4^$%
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 h 3]wL.V
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PaginationSupport的实例ps。 n2)q}_d
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ps.getItems()得到已分页好的结果集 fFb_J`'ue
ps.getIndexes()得到分页索引的数组 3;S,3
ps.getTotalCount()得到总结果数 [0"'T[ok
ps.getStartIndex()当前分页索引 Llr>9(|
ps.getNextIndex()下一页索引 +qh[N@F
ps.getPreviousIndex()上一页索引 > ;/l)qk,
28 8XF9B^
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }ZYv~E'
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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 Z?wU
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一下代码重构了。 1P~X8=9h
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我把原本我的做法也提供出来供大家讨论吧: >}+/{(K"E|
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首先,为了实现分页查询,我封装了一个Page类: ZosP(Tdq
java代码: j#cYS*^H
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/*Created on 2005-4-14*/ $0vb^
package org.flyware.util.page; 6
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/** W[Ls|<Q
* @author Joa {phNds%
* &*+'>UEe5
*/ `DV.+>O-1
publicclass Page { q@[QjGj@
Y;?{|
/** imply if the page has previous page */ _lamn}(x0
privateboolean hasPrePage; V5UF3'3;}
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/** imply if the page has next page */ 9I&xfvD,
privateboolean hasNextPage; nih0t^m'
19w*!FGX
/** the number of every page */ 7Zlw^'q$:L
privateint everyPage; wK?vPS
WA+iYLx@H
/** the total page number */ |S_eDjF
privateint totalPage; Mu+0<>
~ _/(t'9
/** the number of current page */ Qk:Y2mL
privateint currentPage; 8fl`r~bqZ
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/** the begin index of the records by the current
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"N`[r iq{
query */ kqFP)!37
privateint beginIndex; '<"s \,
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/** The default constructor */ 3kybLOG
public Page(){ )h7<?@wv&
e )d`pQ6
} <g$~1fa
!2ZF(@C/
/** construct the page by everyPage ;U-jO &
* @param everyPage nAv#?1cjz
* */ aDU<wxnSvO
public Page(int everyPage){ k$blEa4
this.everyPage = everyPage; Ff)8Q.m
} i<#QW'R (
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/** The whole constructor */ 8WXQOo8
public Page(boolean hasPrePage, boolean hasNextPage, MN\HDKN
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int everyPage, int totalPage, t'n pG}`tE
int currentPage, int beginIndex){ 2LF/H$]o5
this.hasPrePage = hasPrePage; \NPmym_6J
this.hasNextPage = hasNextPage; .P8&5i)'P,
this.everyPage = everyPage; k>;`FFQU>
this.totalPage = totalPage; HiZ*+T.B
this.currentPage = currentPage; nT7%j{e=L
this.beginIndex = beginIndex; r>>%2Z-P
} T&6l$1J
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/** |-:()yxs
* @return GS$ifv
* Returns the beginIndex. Tp/6,EE
*/ v[1aWv:
publicint getBeginIndex(){ :D~D U,e'
return beginIndex; -t!~%_WCv
} 'jWr<]3
rNXQf'*I
/** d;boIP`M;
* @param beginIndex ~vm%6CABM
* The beginIndex to set. Z^3rLCa
*/ Fs9!S a7v
publicvoid setBeginIndex(int beginIndex){ ?9
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this.beginIndex = beginIndex; aTH{'mN
} +$ 'Zf0U
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/** E(>=rD /+
* @return P3x8UR=fS
* Returns the currentPage. (7wc *#}
*/ 5_GYrR2
publicint getCurrentPage(){ M\uiq38
return currentPage; 3lrT3a3vV
} 11Q1AN
/:m->
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/** em%4Ap
* @param currentPage Ni9/}bb
* The currentPage to set. <? q?Mn
*/ YvaK0p0Z
publicvoid setCurrentPage(int currentPage){ "H'B*vc-
this.currentPage = currentPage; J!dm-L
} ,LHn90S
.s?L^Z^
/** #NEE7'&S
* @return L>jY.d2w=K
* Returns the everyPage. {'7B6
*/ - YEZ]:"
publicint getEveryPage(){ ha]VWt%}
return everyPage; ]E5o1eeg
} WlOmJtt4)
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/** Ri<u/ ]oR"
* @param everyPage )1?y 8_B
* The everyPage to set. 3Z>Ux3[
*/ r8`ffH
publicvoid setEveryPage(int everyPage){ |mZxfI
this.everyPage = everyPage; Ytn9B}%o
} KI"#f$2&
Z9v31)q(
/** [_BP)e
* @return d[iQ`YW5
* Returns the hasNextPage. g|o,uD
*/ qU \w=
publicboolean getHasNextPage(){ Q*D;U[
return hasNextPage; qqjwJ!@P
} lU8l}Ndz"
(p" %O
/** 4>wP7`/+y
* @param hasNextPage OIGY`
* The hasNextPage to set. Zu*F#s!tUI
*/ j`{?OYD
publicvoid setHasNextPage(boolean hasNextPage){ 8SMxw~9$
this.hasNextPage = hasNextPage; {5Q!Y&N.%
} owVX*&b{
8 ?xE6
/** /:cd\A}
* @return ju8>:y8
* Returns the hasPrePage. 1KU!
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*/ M H|Og84
publicboolean getHasPrePage(){ #|uCgdi
return hasPrePage; )HEa<P^kJl
} Ki;*u_4{
xK>*yV
/** 3(>B Ke
* @param hasPrePage )*u8/U
* The hasPrePage to set. `}p0VmD{NE
*/ 7y.kQI?3
publicvoid setHasPrePage(boolean hasPrePage){ /T"+KU*
this.hasPrePage = hasPrePage; `aOFs+<)
} * `JYC
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/** 34f?6K1c
* @return Returns the totalPage. *IB4[6
* pE`})/?\*
*/ ]=\].% >
publicint getTotalPage(){ ?e%ZOI
return totalPage; lt/1f{v[:
} !Lu2
]}V<*f
/** V.U|
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* @param totalPage Z3Og=XHR
* The totalPage to set. wi!?BCseq
*/ ?al'F q
publicvoid setTotalPage(int totalPage){ 4VHn \
this.totalPage = totalPage; ><4<yj1
} !Mx$A$Oj>
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} T~-ycVc
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9[#pIPxNK
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 |NlO7aQ>2H
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个PageUtil,负责对Page对象进行构造: ~$ c\JKH-
java代码: 1v y*{D
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/*Created on 2005-4-14*/ B.=FSow
package org.flyware.util.page; .7J#_*NV
pd?Mf=>#
import org.apache.commons.logging.Log; G0Iw-vf
import org.apache.commons.logging.LogFactory; )Om*@;r(
Ao 'l"-
/** -oGdk|Yn
* @author Joa T9=I$@/
* 1Yq!~8
*/ X;$+,&M"
publicclass PageUtil { \$K20)
5%"V[lDx@
privatestaticfinal Log logger = LogFactory.getLog F~-(:7j
u* eV@KK!
(PageUtil.class); /l3V3B7
7^avpf)>
/** +L$Xv
* Use the origin page to create a new page 8|gIhpO?^
* @param page dRYqr}!%n
* @param totalRecords Zpt\p7WQ
* @return *VCXihgo
*/ $t+,Tav
publicstatic Page createPage(Page page, int Dm981t>wL
10Q ]67
totalRecords){ !aUs>1i
return createPage(page.getEveryPage(),
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@FAA2d
page.getCurrentPage(), totalRecords); N%@Qf~
} -OV&Md:~
gb1V~
/** L;z?aZ7n
* the basic page utils not including exception rSY!vkLE\
9
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handler RHW]Z
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* @param everyPage AI2)g1m
* @param currentPage z^B,:5Tt
* @param totalRecords D\v+wp.
* @return page h4gXvPS&r
*/ hPkp;a #
publicstatic Page createPage(int everyPage, int =IZT(8
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currentPage, int totalRecords){ L(6d&t'|-R
everyPage = getEveryPage(everyPage); %uDi#x.
currentPage = getCurrentPage(currentPage); gT.sjd
int beginIndex = getBeginIndex(everyPage, C[cbbp
>>r(/81S
currentPage); yX>K/68
int totalPage = getTotalPage(everyPage, u,ho7ht3(
WCZjXDiwJ
totalRecords); :U|1 xgB
boolean hasNextPage = hasNextPage(currentPage, B`)BZ,#p
e+7"/icK
totalPage); (TtkFo'!U
boolean hasPrePage = hasPrePage(currentPage); NWESP U):w
/8'NG6"H`
returnnew Page(hasPrePage, hasNextPage, K8|r&`X0
everyPage, totalPage, q>_.[+6
currentPage, XSB"{H>&
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beginIndex); $S6`}3
} s[>,X#7 y
XT%nbh&y
privatestaticint getEveryPage(int everyPage){ P;.W+WN
return everyPage == 0 ? 10 : everyPage; <d Wv?<o
} +HpA:]#Y
tU5zF.%
privatestaticint getCurrentPage(int currentPage){ 'ZF{R3Xu
return currentPage == 0 ? 1 : currentPage; 4i;{!sT
} ,<_A2t 2
4\N;2N
privatestaticint getBeginIndex(int everyPage, int !qQl@j O
y-b%T|p9
currentPage){ 1s&zMWC
return(currentPage - 1) * everyPage; u/0h$l
} WDYeOtc
NN{?z!
privatestaticint getTotalPage(int everyPage, int tKuwpT1Qc
"S]0
totalRecords){ X,%
0/6*]
int totalPage = 0; 4"(Bu/24
EWhK0Vej=
if(totalRecords % everyPage == 0) 9rX&uP)j^#
totalPage = totalRecords / everyPage; $99n&t$Y
else `{h*/Q
totalPage = totalRecords / everyPage + 1 ;
NR6#g,+7
Wis~$"
return totalPage; 3pROf#M
} n38p !oS
ub0.J#j@
privatestaticboolean hasPrePage(int currentPage){ Z clQ
return currentPage == 1 ? false : true; Y5Bo|*b
} BwEN~2u6
_.Nbt(mz
privatestaticboolean hasNextPage(int currentPage, Et_bH%0
wWP}C D
int totalPage){ &|1<v<I5
return currentPage == totalPage || totalPage == gs[uD5oo<
2jItq2.>
0 ? false : true; 7F7{)L
} S3 %FHS
-);Wfs
\:'/'^=#|
} Rok7n1gW
UgSB>V<?
Xl{P8L
{<p?2E
| j`@eF/"
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 8'[7
)I=
~W'{p
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 9L?.m&
YlQ=5u^+
做法如下: d"mkL-
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 =o(5_S.u;
9&2O9Nz6
的信息,和一个结果集List: 8^2oWC#U(
java代码: t|\%VC
I*{nP)^9
dL 1tl
/*Created on 2005-6-13*/ 4[r0G+
package com.adt.bo; myQagqRx
~H_/zK6e
import java.util.List; nNV'O(x}
dq6m>;`
import org.flyware.util.page.Page; Fnv;^}\z
}eU*(
}<^
/** ~
'cmSiz-
* @author Joa xh,qNnGGi
*/ \ a<h/4#|
publicclass Result { k,6f
/4V#C-
private Page page; t#})Awy^R
.V/Rfq
private List content; ::lKL
wu!59pL
/** 33x{CY15
* The default constructor bHYy }weZ
*/ X/!o\yyT
public Result(){ 6 7.+
.2
super(); [Td4K.c
} `pa!~|p
{hjhL: pg
/** ~"H,/m%2o
* The constructor using fields {SPq$B_VR
* Oc#syfO
* @param page tjGn|+|k
* @param content l"T44CL;
*/ ]=I@1B;_m
public Result(Page page, List content){ +F` S>U
this.page = page; #e1>H1eU
this.content = content; z&)A,ryW0
} OA1uY83"
T^t#
c
/** drP=A~?&:
* @return Returns the content. %QGC8Tz
*/ m+R[#GE8#
publicList getContent(){ .Wj;%|
return content; gQg"j)
} py!|\00}
t;Sb/ 3
/** QB uMJm
* @return Returns the page. e0zq1XcZ
*/ _$YkM,
public Page getPage(){ <n];mfh1
return page; }Yzco52
} )JLdO*H
nI-w}NQ
/** g"DG]/ev
* @param content *boR`[Ond
* The content to set. SiRaFj4s"
*/ KIf dafRL
public void setContent(List content){ gMmaK0uhS
this.content = content; eS\Vib
} SCHP L.n
vn!3l1\+J
/** 5h-SCB>P
* @param page Tod&&T'UW
* The page to set. &\WSQmtto
*/ BC#C9|n
publicvoid setPage(Page page){ xp)sBM7A
this.page = page; T{.pM4Hd
} ?m}s4a
} 3>AMII
/{aj}M0kN
`l
^9/_g'6
L-WT]&n_
)._; ~z!
2. 编写业务逻辑接口,并实现它(UserManager, Fn;SF4KOm
q4:o#K#
UserManagerImpl) ,+DG2u
java代码: 8,4"uuI
{ ]{/t-=
<4si/=
/*Created on 2005-7-15*/ rdP[<Y9
package com.adt.service; 4{U T!WIi
v5#jZ$<F
import net.sf.hibernate.HibernateException; uM IIYS
ThajHK|U
import org.flyware.util.page.Page; dO<ERY
qZtzO2Mt
import com.adt.bo.Result; EzM
?Nft
N=5a54!/
/** P6-s0]-g
* @author Joa DS(}<HK{
*/ l'-Bu(
publicinterface UserManager { qFCOUl
zm5]J
public Result listUser(Page page)throws wx=
$2N6
?}tFN_X"
HibernateException; *=/ { HvJ
Cazocq5
} @sW24J1q+
+NZ_D#u
RUnSC OdX
_?m(V=z>
Eex~xiiV
java代码: x:NY\._
{M4gF8(M
UT~4x|b:O
/*Created on 2005-7-15*/ [I,Z2G,Jb
package com.adt.service.impl; OUPUixz2Z
~S"+S/z/k
import java.util.List; ifMRryN4
wo;~7K
import net.sf.hibernate.HibernateException; np"\19^
pHXm>gTd,J
import org.flyware.util.page.Page; jUYWrYJ
import org.flyware.util.page.PageUtil; 45@ I *`
oi&VgnSk
import com.adt.bo.Result; HSE!x_$
import com.adt.dao.UserDAO; +ZaSM~
import com.adt.exception.ObjectNotFoundException; B
dj!ia;H
import com.adt.service.UserManager; #C74z$
T= y}y
/** ["k,QX
* @author Joa i/;\7n
*/ Q^9_'t}X
publicclass UserManagerImpl implements UserManager { / |;RV"
ah4N|zJ>v
private UserDAO userDAO; {Qf=G|Ah
H7&8\FNa
/** FF`T\&u
* @param userDAO The userDAO to set. z;,u}u}aI
*/ m{Wu"
;e
publicvoid setUserDAO(UserDAO userDAO){ Y1W1=Uc uk
this.userDAO = userDAO; K,;E5
} ?4#Li~q
+aCv&sg
/* (non-Javadoc) w>s,"2&5J
* @see com.adt.service.UserManager#listUser Y|F9}hj(
E1aHKjLQ
(org.flyware.util.page.Page) g#pr yYz
*/ O-0x8 O^B
public Result listUser(Page page)throws
9]([\% )
r,8 [O
HibernateException, ObjectNotFoundException { 5FPM`hLT
int totalRecords = userDAO.getUserCount(); &v/dj@
if(totalRecords == 0) MO]F1E?X
throw new ObjectNotFoundException 6RU~"C
#>("CAB02T
("userNotExist"); ~|DUt
page = PageUtil.createPage(page, totalRecords); )5Q~I,dP
List users = userDAO.getUserByPage(page); YlJ@XpKM
returnnew Result(page, users); lV3x *4O=
} e{'BAj
Wq D4YGN
} K^)Eb(4
'5#^i:
hohfE3rd
7FP*oN?
_2Zx?<] 2E
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 h9&0Z+zs
!3c\NbU
询,接下来编写UserDAO的代码: 1Z/(G1
3. UserDAO 和 UserDAOImpl: a{'vN93
java代码: g]l''7G
cN-?l7
gS!:+G%
/*Created on 2005-7-15*/ t9GR69v:?
package com.adt.dao; ^,lIK+#Elz
ehGLk7@7&
import java.util.List; HYD'.uj
htO+z7
import org.flyware.util.page.Page; s0TORl6Z|
: %_LpZ
import net.sf.hibernate.HibernateException; g{]0sn#
8rAg\H3E
/** WH#1zv
* @author Joa -lr
vKrt7
*/ [r\Du|R-*
publicinterface UserDAO extends BaseDAO { A_"w^E{P
&)#
ihK_
publicList getUserByName(String name)throws niMsQ
/e5O"@
HibernateException; :[.vM
IEL%!RFG
publicint getUserCount()throws HibernateException; 6fE7W>la
[t m_Mg
publicList getUserByPage(Page page)throws bi',j0B
:;%2BSgFU
HibernateException; KC*e/J
y;m|
}
i<C*j4qQ
UP$.+<vm
w8")w*9Lmg
9d0@wq.
=g7x'
kN
java代码: ;Zcswt8]u
ih-#5M@
gMi0FO'
/*Created on 2005-7-15*/ ]\-A;}\e
package com.adt.dao.impl; ch*8B(:
>4x(e\B
import java.util.List; { T/[cu<
T=
8 0,
import org.flyware.util.page.Page; \i>?q
3,_aAgeE
import net.sf.hibernate.HibernateException; o"s)eh
import net.sf.hibernate.Query; W<h)HhyG
k&M;,e3v6
import com.adt.dao.UserDAO; `z}?"BW|
]? c
B:}
/** Ye%~I`@?
* @author Joa ydEoC$?0
*/ xWH.^o,"
public class UserDAOImpl extends BaseDAOHibernateImpl ?.m bK
>F|>cc>_E
implements UserDAO { 6$hQ35
M5LfRBO
/* (non-Javadoc) ~gJwW+
* @see com.adt.dao.UserDAO#getUserByName [Q~#82hBhY
C#.->\
(java.lang.String) O#4&8>;=
*/ i'<[DjMDlm
publicList getUserByName(String name)throws 9Z$"K- G
F@D`N0Pte
HibernateException { `{@8Vsmy:
String querySentence = "FROM user in class A;q9rD,_
"m):Y;9iQ?
com.adt.po.User WHERE user.name=:name"; ^do9*YejX;
Query query = getSession().createQuery ,C\i^>=
djl*H
(querySentence); #Qw0&kM7I
query.setParameter("name", name); .fqN|[>
return query.list(); c1(RuP:S
} .|KyNBn
)N{Pw$l_
/* (non-Javadoc) G{~J|{t\yz
* @see com.adt.dao.UserDAO#getUserCount() (Bb5?fw
*/ EmWn%eMN
publicint getUserCount()throws HibernateException { AG
nxYV"p
int count = 0; G6Axs1a
String querySentence = "SELECT count(*) FROM fivw~z|[@
zy?|ODM
user in class com.adt.po.User"; 3@_xBz,I .
Query query = getSession().createQuery 0(}t8lc
f].h^~.q
(querySentence); PA{PD.4Du
count = ((Integer)query.iterate().next dw>C@c#"
_gR;=~S
()).intValue(); KJUH(]>F
return count; (*9$`!wS
} C\3rJy(VJ
FW;?s+Uyx
/* (non-Javadoc) ]Jg&VXrH
* @see com.adt.dao.UserDAO#getUserByPage 4HXo >0
H\" sgoJ
(org.flyware.util.page.Page) Wx%H%FeK
*/ kOrZv,qFG[
publicList getUserByPage(Page page)throws JAnZdfRt
wD}l$& +
HibernateException { .&iawz
String querySentence = "FROM user in class IVnHf_PzF
23eX;gL
com.adt.po.User"; m#Jmdb_
Query query = getSession().createQuery |)DGkOtd
HXC ;Np
(querySentence); ITX a&5D
query.setFirstResult(page.getBeginIndex()) fSj5ZsO
.setMaxResults(page.getEveryPage()); 7vKK%H_P
return query.list(); F@jZ ho
} VR 8-&N
WF+99?75
} V]6dscQ
;6
D@A
ea2ayT
r EE1sy/#
K=Z|/Kkh
至此,一个完整的分页程序完成。前台的只需要调用 )gUR@V>e2
\fLMr\LL&
userManager.listUser(page)即可得到一个Page对象和结果集对象 \ A#41
Q~]uC2Mw
的综合体,而传入的参数page对象则可以由前台传入,如果用 F`W?II?
c9
eM/*:
webwork,甚至可以直接在配置文件中指定。 Oc0a77@
U[-o> W#
下面给出一个webwork调用示例: 9MJG;+B~
java代码: 2%Ri,4SRb
]L.O8
_Kf% \xg
/*Created on 2005-6-17*/ 3AtGy'NTp
package com.adt.action.user; q-2Bt,Y
]IQ&>z}<
import java.util.List; yjX9oxhtL
K&]G3W%V
import org.apache.commons.logging.Log; A2Ed0|B y
import org.apache.commons.logging.LogFactory; z (wc0I
import org.flyware.util.page.Page; x.6:<y
ibk6|pp
import com.adt.bo.Result; >Eto(
y"q
import com.adt.service.UserService; K#d`Hyx
import com.opensymphony.xwork.Action; ;(Or`u]Dr
CNyIQ}NJ
/** DU'`ewLL7
* @author Joa CAWNDl4
*/ BoWg0*5xb
publicclass ListUser implementsAction{ (k.[GfCbD
1N-\j0au
privatestaticfinal Log logger = LogFactory.getLog Y\k#*\'Y~
z'n:@E
(ListUser.class); b94DJzL1z
{$
JYw{a
private UserService userService; *u [BP@vE
&)ChQZA
private Page page; U(g:zae
L|xbR#v
privateList users; 0RLg:SV
Qbn"=n2
/* "Ac-tzhE
* (non-Javadoc) dn+KH+v
* s} ;{ZAtE
* @see com.opensymphony.xwork.Action#execute() ?Ep [M:,q
*/ K=k"a
publicString execute()throwsException{ n
M*%o-
Result result = userService.listUser(page); }2.`N%[
page = result.getPage(); WX?IYQ+
users = result.getContent(); k$R-#f;
return SUCCESS; Y"aJur=`
} nRS} }6Q
?P`K7
/** a~}OZ&PG
* @return Returns the page. oW*16>IN9l
*/ 0R'?~`aTt
public Page getPage(){ !)0;&e5
return page; d.d/<
} Id .nu/
6ojo :-%Vf
/** .}TZxla0Zr
* @return Returns the users. <uw9DU7G
*/ x2\qXN/R
publicList getUsers(){ f+,qNvBY/
return users; [!#L6&:a8
} K`zdc`/
m@v\(rT.
/** K=h9Ce
* @param page /]Md~=yNp
* The page to set. h2]P]@nW;W
*/ SsDmoEeB[
publicvoid setPage(Page page){ c9 _rmz8
this.page = page; qiBVGH
} :>f )g
@,7GaK\
/** k)=s>&hl
* @param users jcf7n`L
* The users to set. joAv{Tc
*/ f+)L#>Gl?
publicvoid setUsers(List users){ C1n>M}b
this.users = users; H3=qe I
} ,j_i?Ff
!``,gExH
/** u^I|T.w<r6
* @param userService j-}O0~Jz
* The userService to set. 29] G^f>
*/ '4Bm;&6M
publicvoid setUserService(UserService userService){ EUX\^c]n
this.userService = userService; O;jrCB
} aSQ#k;T[
} /%1ON9o>
2-v%`fA
!PQ<04jA!
y/7\?qfTk
xdt-
;w|
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, Q\7h`d%)
Ie#Bkw'*
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 vr6w^&[c^
A]oV"`f
么只需要: "JV_ 2K_i
java代码: hD!7Cl Q
uZKr
V6X 0^g
<?xml version="1.0"?> rw JIx|(
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Ioa$51&
jLm ;ty2;
1.0//EN" "http://www.opensymphony.com/xwork/xwork- qqY"*uJ'
oAeUvmh
1.0.dtd"> 2uW;
xfeY
0IBSRFt$g&
<xwork> Am|%lj+1z
aeM+ d`f
<package name="user" extends="webwork- Om2d.7S
?NsW|w_
interceptors"> ZKTz
,
;h
<!-- The default interceptor stack name ;dgp+
7[XRd9a5(
--> +\
.Lp 5
<default-interceptor-ref >KhOz[Zg
:':s@gqr
name="myDefaultWebStack"/> 9qzHS~l
0 /U{p,r6`
<action name="listUser" K is"L(C
6O! 2P
class="com.adt.action.user.ListUser"> i<Zc"v;
<param VjZ|$k
`b7t4d*
name="page.everyPage">10</param> }WXi$(@v
<result 2pa5U;u:+
hhc,uJ">!
name="success">/user/user_list.jsp</result> 7ZWgf"1j
</action> y766;
X:J
lq;Pch
</package> 8'io$6d=
v`Oc,
</xwork> c,+:i1IAy
'I6i,+D/q
M%P:n/j
,w4V?>l
aj{Y\
3L
m~0/&RA
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 $B5aje}i
tFOhL9T
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 w+u3*/Zf
-X2Buz8
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 |t#)~Oo
I:1C8*/
U8n V[
M-Y_ Wb3
!wh8'X*
我写的一个用于分页的类,用了泛型了,hoho =MDysb&:
],Do6
@M-
java代码: P{lB50
sWnLEw
;+hH
package com.intokr.util; v;D~Pa
YO}<Ytx
import java.util.List; /!XVHkX[
LBDjIpR6
/**
HvJs1)Wo&
* 用于分页的类<br>
_
*Pf
* 可以用于传递查询的结果也可以用于传送查询的参数<br> +Q"4Migbe@
* VQOezQs\
* @version 0.01 >@
.
* @author cheng &Hs!:43E-<
*/ 3{sVVq5Y
public class Paginator<E> { T'Dv.h
privateint count = 0; // 总记录数 a~y'RyA
privateint p = 1; // 页编号 V/9!K%y
privateint num = 20; // 每页的记录数 ]2qo+yB
privateList<E> results = null; // 结果 uiR8,H9*M
DT&@^$?
/** |[b{)s?x
* 结果总数 ,UF_`|
*/ Fd9[pU
publicint getCount(){ 0*{%=M
return count; )|#sfHv7
} gT6jYQ
Ok=hT|}Y
publicvoid setCount(int count){ )oPBa
this.count = count; bq0zxg%
} 'YSHi\z ](
z9Rp`z&`E
/** 3eQ&F~S
* 本结果所在的页码,从1开始 `*1p0~cu
* AFE~
v\Gz
* @return Returns the pageNo. d<P\&!R(
*/ hv>\gBe i
publicint getP(){ Qj3EXb
return p; 8&b,qQ~
} O)r4?<Q
%| Lfuz*
/** ^SrJu:Q_
* if(p<=0) p=1 OYn}5RN
* FXkM#}RgNm
* @param p IF:;`r@%
*/ Zp=U
W*g^
publicvoid setP(int p){ }b.%Im<3R
if(p <= 0) v"Es*-{B
p = 1; U
z>+2m(
this.p = p; g{&ui.ml&
} ^.QzQ1=D
D2~*&'4y
/** XVZ
* 每页记录数量 amY!qg0P*
*/ {&1/V
publicint getNum(){ f9{Rb/l!BQ
return num; [Y|t]^M
} Z4
=GMXj
1o{Mck
/** Q>Yjy!.<^
* if(num<1) num=1 VRB;$
*/ ^s"R$?;h
publicvoid setNum(int num){ dDLeSz$b
if(num < 1) I51@QJX
num = 1; {F.[&/A
this.num = num; 1/J=uH
} 9~[Y-cpoi
7WZ+T"O{I
/** o0KL5].
* 获得总页数 ##" HF
*/ JT_ `.(
publicint getPageNum(){ BLD gt~h#
return(count - 1) / num + 1; A6(/;+n
} +@wD qc
*(DV\. l`
/** vUM4S26"NT
* 获得本页的开始编号,为 (p-1)*num+1 P+/e2Y
*/ zIAD9mQex
publicint getStart(){ $1`2kM5
return(p - 1) * num + 1; cSV aI
} DN:EB@
l!u_"I8j5
/** g]0_5?i
* @return Returns the results. P-"y3 ZE=
*/ 7zG_(83)K
publicList<E> getResults(){ [.wYdv35
return results; xU`p|(SS-
} H9e<v4c
&
>fQp(f
public void setResults(List<E> results){ _.8S&
this.results = results; #AQV(;r7@
} /IMFO:c
0n{=%Q
public String toString(){ I
b5rqU\
StringBuilder buff = new StringBuilder Ig>(m49d
o?\?@H
(); /%io+94
buff.append("{"); tY4;F\e2|A
buff.append("count:").append(count); Qzw;i8n{
buff.append(",p:").append(p); /mzlH
buff.append(",nump:").append(num); i=2N;sAl
buff.append(",results:").append }0Ed]
e$rZ5X
(results); l,5+@i`5i
buff.append("}"); t*w/{|yO
return buff.toString(); 7-fb.V9
} }@d @3
\,0oX!<YY
} }k.Z~1y
ncT&Gr
'6%2.[o