Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 w>8HS+
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 *+zFsu4l
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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 SHs [te[
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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 GZWqPM4S\
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分页支持类: 0ETT@/)]z
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java代码: x]yIe&*('
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package com.javaeye.common.util; V,rR*a&p
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import java.util.List; l?$X.CwX
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publicclass PaginationSupport { n Bd]rak'
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publicfinalstaticint PAGESIZE = 30; j94~cYV
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privateint pageSize = PAGESIZE; +,,dsL
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privateList items; Iila|,cM
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privateint totalCount; pY-!NoES
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privateint[] indexes = newint[0]; n-SO201[*
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privateint startIndex = 0; rz,,ku4qt
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public PaginationSupport(List items, int @GD $KR9
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totalCount){ lz6CK
setPageSize(PAGESIZE); n|? sNM<J3
setTotalCount(totalCount); zRmVV}b
setItems(items); H;NAS/OhS
setStartIndex(0); wl%ysM|x
} m'
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public PaginationSupport(List items, int g33Y$Xdk
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totalCount, int startIndex){ ]hy@5Jyh
setPageSize(PAGESIZE); :Cezk D&
setTotalCount(totalCount); Z2@e~&L
setItems(items); fd #QCs
setStartIndex(startIndex); n^$Q^[:Z
} 0[fBP\H"Wr
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public PaginationSupport(List items, int ^7ID |uMr
shL_{}
totalCount, int pageSize, int startIndex){ x^c,cV+*
setPageSize(pageSize); c%O97J.5b
setTotalCount(totalCount); aCH;l~+U
setItems(items); c$)>$&([
setStartIndex(startIndex); `n-/~7
} ?7TmAll<.s
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publicList getItems(){ =w;-4
return items; -xLK/QAL
} ;nL7Hizo,
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publicvoid setItems(List items){ |A,.mOT
this.items = items; _-H,S)kI`
} Vt \g9-[
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publicint getPageSize(){ 9{geU9&Z
return pageSize; nh0gT>a>@
} <+r~?X_
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publicvoid setPageSize(int pageSize){ `Ix`/k}
this.pageSize = pageSize; K@DFu5
} 'AWWdz
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publicint getTotalCount(){ }eA)m
return totalCount; UroC8Tm
} 2"|7 YI
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publicvoid setTotalCount(int totalCount){ 82+2PE{
if(totalCount > 0){ /=l!F'
this.totalCount = totalCount; l&e{GHz
int count = totalCount / O(-6Zqk8Q
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pageSize; >'=9sCi
if(totalCount % pageSize > 0) %Qb}z@>fJk
count++; D3,)H%5.y
indexes = newint[count]; LttA8hf5q?
for(int i = 0; i < count; i++){ js;YSg{m
indexes = pageSize * gBWr)R
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i; J#j3?qrxu
} <Piq?&VX[
}else{ ZybfqBTD&c
this.totalCount = 0; Wl=yxJu_(
} TG8 U=9qt
} m5]
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publicint[] getIndexes(){ {|OXiRm'
return indexes; S76MY&Vx23
} YMNLn9
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publicvoid setIndexes(int[] indexes){ G#f3
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this.indexes = indexes; 8 l= EL7
} ^*UtF9~%n
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publicint getStartIndex(){ w'_|X&@H
return startIndex; fWW B]h
} GV) "[O
}#M>CNi'PU
publicvoid setStartIndex(int startIndex){ #H
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if(totalCount <= 0) ?-o_]!*v0/
this.startIndex = 0; )h>dD
elseif(startIndex >= totalCount) ]oz >/\!
this.startIndex = indexes ^jb;4nf
ndT_;==
[indexes.length - 1]; !a\HdQ
elseif(startIndex < 0) 9An\uH)mL
this.startIndex = 0; ?li/mc.XG
else{ Sfc,F8$&N
this.startIndex = indexes H/ Ql
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[startIndex / pageSize]; B<Cg_C
} ^.g-}r8,
} ~,)D
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publicint getNextIndex(){ x./"SQ=R+
int nextIndex = getStartIndex() + l O*
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pageSize; -vc$I=b;
if(nextIndex >= totalCount) =\oW{?
return getStartIndex(); Ma(Q~G
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else wL]#]DiE
return nextIndex; `HYj:4v'
} 2?:OsA}
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publicint getPreviousIndex(){ MT)q?NcG
int previousIndex = getStartIndex() - ^r(]S%
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pageSize; PA*k|
if(previousIndex < 0) ?UIW&*h}
return0; Z 5P4 H
else l=Jw6F+5
return previousIndex; pV\ >?
} <"3${'$k`
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} -bSM]86
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抽象业务类 car|&b
java代码: p/7'r
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/** x;} 25A|
* Created on 2005-7-12 31#jLWY'0
*/ *V+,X
package com.javaeye.common.business; xC0y2+)|
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import java.io.Serializable; ,z`D}<3
import java.util.List; <}c7E3Uc
vpdPW %B
import org.hibernate.Criteria; :f_oN3F p
import org.hibernate.HibernateException; :P%?!'M
import org.hibernate.Session; m MWhUr
import org.hibernate.criterion.DetachedCriteria; rFm?Bu
import org.hibernate.criterion.Projections; c(b`eUOO
import Bf+~&I#E
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org.springframework.orm.hibernate3.HibernateCallback; ![vy{U.:`
import g3Hi5[-H
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org.springframework.orm.hibernate3.support.HibernateDaoS 8WpNlB+:{
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upport; q&NXF(
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import com.javaeye.common.util.PaginationSupport; +!nf?5;
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public abstract class AbstractManager extends
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HibernateDaoSupport { \`2EfYJ{
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privateboolean cacheQueries = false;
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privateString queryCacheRegion; G-]<+-Q$4
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publicvoid setCacheQueries(boolean Nr)DU.f
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cacheQueries){ qx*b\6Rt
this.cacheQueries = cacheQueries; [0kZyjCq@
} 8ql<7RTM!
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publicvoid setQueryCacheRegion(String P%vouC0W
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queryCacheRegion){ @7Ln1v
this.queryCacheRegion = .A6pPRy e
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queryCacheRegion; H0t#J
} -=UvOzw
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publicvoid save(finalObject entity){ Yb[)ETf^
getHibernateTemplate().save(entity); pa?AKj]
} 87)/dHc
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publicvoid persist(finalObject entity){ T-7(3#&
getHibernateTemplate().save(entity); k{lX K\zN
}
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publicvoid update(finalObject entity){ 3|)cT1ej
getHibernateTemplate().update(entity); A5 4u}
} j!;E>`g
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publicvoid delete(finalObject entity){ ~]<VEji
getHibernateTemplate().delete(entity); a?Y> hvI
} oz|+{b}%
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publicObject load(finalClass entity, < %<nh`D
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finalSerializable id){ S?D]P'<
return getHibernateTemplate().load z
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(entity, id); Wap\J7NY
} #\_FSr fX
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publicObject get(finalClass entity, =0;njL(7;
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finalSerializable id){ gd7!+6
return getHibernateTemplate().get ~qTChCXP
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(entity, id); mT|r:Yr:
} qkC{IBN92
QMX
publicList findAll(finalClass entity){ 5s4x%L (~}
return getHibernateTemplate().find("from .;,,{;
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" + entity.getName()); WigTNg4
} 2sEG#/Y=
}#=t%uZ/
publicList findByNamedQuery(finalString : ?Z9
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namedQuery){ Y$|KY/)H)
return getHibernateTemplate dEX67rUj;
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().findByNamedQuery(namedQuery); c0X1})q$
} *`Ge8?qC
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publicList findByNamedQuery(finalString query, (58r9WhS
+OSSgY$
finalObject parameter){ 'cK{FiIT
return getHibernateTemplate 5;XU6Rz!
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().findByNamedQuery(query, parameter); *8u<?~9F
} a%an={
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publicList findByNamedQuery(finalString query, !#
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finalObject[] parameters){ a|]}uFr
return getHibernateTemplate D&],.N
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().findByNamedQuery(query, parameters); P/k#([:2
} G \$x.
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publicList find(finalString query){ mWLi XKnb
return getHibernateTemplate().find 4JH^R^O<n
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(query); e%9zY{ABR%
} l Yj$3
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publicList find(finalString query, finalObject V-63
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parameter){ oXVx9dZ
return getHibernateTemplate().find i"4;{C{s
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(query, parameter); .i#'IS0c
} ]&='E.f
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public PaginationSupport findPageByCriteria (8N E'd8
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(final DetachedCriteria detachedCriteria){ }p8iq
return findPageByCriteria "412w^5[T
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Tx'anP
} 4:s,e<Tc4v
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public PaginationSupport findPageByCriteria br?pfs$U
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(final DetachedCriteria detachedCriteria, finalint 8@FgvWC
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startIndex){ DW)81*~g
return findPageByCriteria 9R[PpE''
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(detachedCriteria, PaginationSupport.PAGESIZE, >LVGNicQ
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startIndex); LMp^]*)t
} 19Mu}.+;
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public PaginationSupport findPageByCriteria <?Z]h]C^o
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(final DetachedCriteria detachedCriteria, finalint |h.@Xy
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pageSize, , $cpm=1
finalint startIndex){ %T}*DC$&S
return(PaginationSupport) oC3W_vH.%
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getHibernateTemplate().execute(new HibernateCallback(){ L /N%ft]!T
publicObject doInHibernate dTwYDV}:
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(Session session)throws HibernateException { A":cS }Ui
Criteria criteria = JEeXoGKd
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detachedCriteria.getExecutableCriteria(session); bq}`jP~#
int totalCount = #aE>-81SS&
)3 '8T>^<K
((Integer) criteria.setProjection(Projections.rowCount -O $!sFmY
*3fhVl=8^*
()).uniqueResult()).intValue(); I 6L3M\+-
criteria.setProjection iBY16_q
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(null); ahN8IV=+Gm
List items = ;2aPhA
be(hY{y`
criteria.setFirstResult(startIndex).setMaxResults "z*?#&?,
8 9maN
(pageSize).list(); !&{"tL@.
PaginationSupport ps = E>u U6#v
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new PaginationSupport(items, totalCount, pageSize, m mH
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startIndex); Fj`K$K?
return ps; #9HX"<5
} M>{*PHze0
}, true); K d{o/R
} xi)$t#K"
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public List findAllByCriteria(final Uu9I;q!|
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DetachedCriteria detachedCriteria){ ]L
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return(List) getHibernateTemplate Y3H5}4QD
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().execute(new HibernateCallback(){ ^h2!u'IQ
publicObject doInHibernate c1
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(Session session)throws HibernateException { TRE D_6
Criteria criteria = 0W)|n9
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detachedCriteria.getExecutableCriteria(session); Q5Epq
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return criteria.list(); -\25&m!+
} sDBwD%sb
}, true); xO4""/n
} *bzqH 2h8
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public int getCountByCriteria(final R.YUUXT
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DetachedCriteria detachedCriteria){ 64Tb,AL_
Integer count = (Integer) ?gMq:[XN
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getHibernateTemplate().execute(new HibernateCallback(){ Bc'Mj=>;
publicObject doInHibernate +DE;aGQ.z?
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(Session session)throws HibernateException { _SMi`ie#
Criteria criteria = !Yz
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detachedCriteria.getExecutableCriteria(session); \:2z!\iP`
return b&RsxW7
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criteria.setProjection(Projections.rowCount O.{
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()).uniqueResult(); 7/)0{B4U'
} =JxEM7r
}, true); Z=]ujlD
return count.intValue(); ;
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} 7t/Y5Qf
} h\+8eeIl
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用户在web层构造查询条件detachedCriteria,和可选的 g@Rs.Zq
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {e0(M*u
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PaginationSupport的实例ps。 Q(4~r+
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ps.getItems()得到已分页好的结果集 . "7-f]!
ps.getIndexes()得到分页索引的数组 G9@5 !-
ps.getTotalCount()得到总结果数 ^~dC&!D
ps.getStartIndex()当前分页索引 0 1NP
ps.getNextIndex()下一页索引 >4os%T
ps.getPreviousIndex()上一页索引 ,V{Bpr
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 K#VGG,h7Y
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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 \C{Zqo,
/)<kG(Z
一下代码重构了。 .kJu17!
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我把原本我的做法也提供出来供大家讨论吧: b1%w+* d<z
[ u ^/3N
首先,为了实现分页查询,我封装了一个Page类: +-|}<mq
java代码: XD80]@\za
9Q\RCl_1
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/*Created on 2005-4-14*/ *e:2iM)8~
package org.flyware.util.page; 4
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/** *^CN2tm
* @author Joa pimI)1 !$'
* MPF({Pnx7
*/ x6^FpNgQ
publicclass Page { 9#kk5 )J
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/** imply if the page has previous page */ 12: Q`
privateboolean hasPrePage; XEN-V-Z%*
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/** imply if the page has next page */ [w)KNl
privateboolean hasNextPage; O3pd5&^g
.')^4\
/** the number of every page */ Dw
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privateint everyPage; E )2/Vn2
Dj 6^|R$z&
/** the total page number */ vFeR)Ox's
privateint totalPage; GH&5m44
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/** the number of current page */ nP|ah~
q
privateint currentPage; ngk:q5Tp
^ (J%)&_\3
/** the begin index of the records by the current Nz%pl!
j HObWUX
query */ B[2t.d;h
privateint beginIndex; N
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/** The default constructor */ ;ZkY[5
public Page(){ [jEA|rd~}
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} -iFFXESVX
*z_`$Y
/** construct the page by everyPage =5:kV/p
* @param everyPage 6j|~oMYP
* */ b{X.lz0
public Page(int everyPage){ rA@|nL{
this.everyPage = everyPage; jR*iA3LDo
} }r"E\~E
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/** The whole constructor */ P]L%$!g
public Page(boolean hasPrePage, boolean hasNextPage, $#wi2Ve=6b
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Lmw)Ts>
int everyPage, int totalPage, A{\DzUV9,
int currentPage, int beginIndex){ [g{fz3
O6
this.hasPrePage = hasPrePage; >)mF'w
this.hasNextPage = hasNextPage; KvI/!hl\
this.everyPage = everyPage; "cbJ{ G1pk
this.totalPage = totalPage; `iEYq0}
this.currentPage = currentPage; &v9"lR=_k
this.beginIndex = beginIndex; C;9P6^Oz
} _T=";NSa
`wSoa#U"@
/** ^}:0\;|N
* @return r]kks_!Z
* Returns the beginIndex. .'2"83f
*/ S'>KGdF
publicint getBeginIndex(){ %O{FZgi%wA
return beginIndex; uVXn/B
} vY[u;VU
u/N_62sk5
/** dN){w _
* @param beginIndex CurU6x1
* The beginIndex to set. ?Qts2kae#
*/ ;#*.@Or@Ah
publicvoid setBeginIndex(int beginIndex){ h645;sb0
this.beginIndex = beginIndex; L$ jii
} `];ne]xM
Ad-_=a%
/** !L_xcov!Y
* @return s"8z q;)
* Returns the currentPage. BL%&n*&
*/ 715J1~aRNr
publicint getCurrentPage(){ |@?='E?h
return currentPage; kpk ^Uw%f
} FE#|5;q.
ONc#d'-L
/** 8zwH^q[`r
* @param currentPage F'_z$,X6
* The currentPage to set. .li)k[] ts
*/ #X6=`Xe#
publicvoid setCurrentPage(int currentPage){ m5hu;>gt
this.currentPage = currentPage; EAF\7J*
} z,VXH ?.Zo
77 ?TRC
/** Q1H.2JXr
* @return % 5BSXAc
* Returns the everyPage. C3 m_sv#e
*/ Gr3 q
publicint getEveryPage(){ !=+;9Ry$z
return everyPage; Q0xQxz
} Z(J
1A x
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/** ?w)A`G_
* @param everyPage 48!F!v,j)x
* The everyPage to set. ]!@!qp@
*/ J.0&gP V
publicvoid setEveryPage(int everyPage){ TJ,?C$3
this.everyPage = everyPage; F[fs^Q6S$
} Kke
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LD ,T$"
/** E,4*a5Fi
* @return }E)t,T>
* Returns the hasNextPage. s2nZW pIy
*/ >PGsY[N
publicboolean getHasNextPage(){ YT@H^=
return hasNextPage; 9Lqz:4}
} ,yi@?lc
Pfm B{
/** lI5>d(6p
* @param hasNextPage #4Cf-$J
* The hasNextPage to set. lB|.TCbW
*/ :[Ie0[H/M
publicvoid setHasNextPage(boolean hasNextPage){ #;"lBqxY`
this.hasNextPage = hasNextPage; zEeix,IU
} (k%r_O 6
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/** 8#Y_]Z?)
* @return %\%&1
* Returns the hasPrePage. mn\GLR.
*/ Qb:.WMj[q+
publicboolean getHasPrePage(){ XK(aH~7xme
return hasPrePage; nYK!'x$
} vE~<R
@_h=,g#@
/** v/`#Gu^P
* @param hasPrePage s1T}hp
* The hasPrePage to set. 14y>~~3C4
*/ <-Ax)zE
publicvoid setHasPrePage(boolean hasPrePage){ "fSK7%BP
this.hasPrePage = hasPrePage; TI7)yxa=`
} W'Qy4bl7C
S @)P#
/** %@;xbKj
* @return Returns the totalPage. mQtOx
* NV`7VYU
*/ Btc[
publicint getTotalPage(){ o:Tpd 0F
return totalPage; _^^5
} 6V1
Z(K
}oii|=,#^
/**
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* @param totalPage *(VwD)*
* The totalPage to set. V_)465g
*/ xf{=~j/L
publicvoid setTotalPage(int totalPage){ 4{"
v
this.totalPage = totalPage; C7Hgzc|U
} p vu% p8
COSQ
} Z0Qh7xWve
q4u-mM7#7
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~@iYP/=/Q
1,6Y)_
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 ?/KkN3Y_j[
*@&V=l
个PageUtil,负责对Page对象进行构造: "6iq_!#L
java代码: A@ w9_qo
v<?k$ e5
PO=A^ b
/*Created on 2005-4-14*/ 8noo^QO
package org.flyware.util.page; xllmF)]*Y
75']fFO@!
import org.apache.commons.logging.Log; ;B"S*wYMN
import org.apache.commons.logging.LogFactory; &F +hh{
RD*.n1N1
/** %#7^b=;=
* @author Joa ATI2
* 0&2&F=fOa<
*/ $H7T|`WI.,
publicclass PageUtil { a3BlydSlf
SvD:UG
privatestaticfinal Log logger = LogFactory.getLog )"^ )Nk
Y-*]6:{E
(PageUtil.class); ;3sJ7%`v
x]:B3_qR
/** B{Lcx ~
* Use the origin page to create a new page |JCn=v@
* @param page P/dT;YhL
* @param totalRecords "J3n_3+
* @return "ODs.m oq
*/ RSf*[2
publicstatic Page createPage(Page page, int l' a<k"
n UD;y}}n
totalRecords){ w;T?m,"
return createPage(page.getEveryPage(), ~ponYc.Y
.BZ3>]F3<
page.getCurrentPage(), totalRecords); Uj~
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} 6XGqZ!2
h)yAge
/** j}$Q`7-wB1
* the basic page utils not including exception &0euNHH;sL
u-~?ylh
handler J<7nOB}OD
* @param everyPage
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* @param currentPage
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* @param totalRecords ]WC@*3'kye
* @return page >)iCKx
*/ V?Ye^-29
publicstatic Page createPage(int everyPage, int K#'{Ko
8'Bik
currentPage, int totalRecords){ {;Y2O.lV
everyPage = getEveryPage(everyPage); tje
currentPage = getCurrentPage(currentPage); Pb@9<N Xm'
int beginIndex = getBeginIndex(everyPage, KEvT."t
\g\,
currentPage); 8@4)p.{5I
int totalPage = getTotalPage(everyPage, *'ex>4^
#5W-*?H
totalRecords); ik|iAWy
boolean hasNextPage = hasNextPage(currentPage, 'B$qq[l]S
E.OL_ \
totalPage); q|ww fPez7
boolean hasPrePage = hasPrePage(currentPage); R9V v*F]m@
5y|/}D>
returnnew Page(hasPrePage, hasNextPage, a`uHkRX
)U
everyPage, totalPage, ,;-55|o\V
currentPage, ]abox%U=%
_l!TcH+e
beginIndex); +;wu_CQu
} /YH5s=
ih/MW_t=m=
privatestaticint getEveryPage(int everyPage){ HESORa;
return everyPage == 0 ? 10 : everyPage; j`kw2(
} X{bqG]j
uE{nnNZy
privatestaticint getCurrentPage(int currentPage){ vOYG&)Jm
return currentPage == 0 ? 1 : currentPage; B*j
AD2
} tV,Y38e
`O|PP3S
privatestaticint getBeginIndex(int everyPage, int !&OybjQ
Z'L}x6
currentPage){ Y;WHjW(K
return(currentPage - 1) * everyPage; O(oGRK<xM
} ~Fd<d[b?
eZ~ZWb, %
privatestaticint getTotalPage(int everyPage, int t9B]V
U.HeIJ#
totalRecords){ !FVXNl
int totalPage = 0; +gQoYlso
mOvwdRKn
if(totalRecords % everyPage == 0) +c^[[ K"
totalPage = totalRecords / everyPage; C@i4[g){
else #x;i R8^
totalPage = totalRecords / everyPage + 1 ; 3mnq=.<(w
-Am~CM
return totalPage; S+EC!;@Xg
} -h<Rby
SMdQ,n1]
privatestaticboolean hasPrePage(int currentPage){ amK.H"
return currentPage == 1 ? false : true; Fn~?YN
} U`fxe`nVa
]Kb3'je
privatestaticboolean hasNextPage(int currentPage, A!Ls<D.
~L.)<{?
int totalPage){ 'rwnAr
return currentPage == totalPage || totalPage == sOBy)vq?\
5ZkMd!$y
0 ? false : true; LMmW3W`
} Be(h x
Jm+;A^;
;8
D31OT
} 7TjK;w7xS.
7#BpGQJQ
hw [G
K2glkGK
_pv<_
Sm
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。 cR+9^DzA
b^Xq(q>5
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 HJ2r~KIw
P]4C/UDS-~
做法如下: BtN@P23>k.
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 )wROPA\uA
> ^b6\
的信息,和一个结果集List: gUoTOA,
java代码: xxh(VQdg
U`es
n?m!
MDCK@?\
/*Created on 2005-6-13*/ l`s_#3
package com.adt.bo; k]=Yi;
$6a55~h|(
import java.util.List; =sk]/64h``
}. x&}FqXE
import org.flyware.util.page.Page; hi I`ot
?-P]m&nh|
/** G#&R/Tc5N
* @author Joa G:e9}
*/ %hzl3>().
publicclass Result { x7=5 ;gf/X
rQ^$)%uP
private Page page; p}j$p'D.RI
n)(E 0h
private List content; 4{d!}R
"+2Hde1
/** u[_~ !y
* The default constructor b NBpt}$
*/ V3'QA1$
public Result(){ h-Q3q:
super(); , wT$L3
} 4%TY`
II
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/** <B*}W2\
* The constructor using fields %{*}KsS`p
* TlD)E
* @param page 9WaKs d f
* @param content %Bo/vB'
*/ LO,G2]
public Result(Page page, List content){ LB|FVNW/S
this.page = page; p-H q\DP
this.content = content; ).0h4oHSj
} R!i9N'gGG(
cCd2f>EHw
/** );*A$C9RA
* @return Returns the content. FfnW
*/ 821@qr|`e
publicList getContent(){ mJaWzR
return content; }];8v+M
} +j._NRXRH
?3wEO>u
/** URq{#,~CT
* @return Returns the page. HY.??
5MH
*/ L=u>}?!,Fj
public Page getPage(){ UC)-Fd
return page; T&Y?IE}
} 3_JxpQg
E"e <9
/** $=/.oh
* @param content Hf
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* The content to set. $0C1';=^}
*/ 8}FZ1h2
4
public void setContent(List content){ Tz H*?bpP
this.content = content; Farcd!}
} /`YHPeXu
#\kYGr-G)
/** %Y"@VcN
* @param page [:geDk9O#'
* The page to set. Tti]H9g_
*/ N'nI
^=
publicvoid setPage(Page page){ ]Ma2*E!p
this.page = page; gw0b>E8gZ&
} w{J0K;L
} ^PY*INv
#WD}XOA
fHek!Jv.
uUXvBA?l
6mr5`5~w
2. 编写业务逻辑接口,并实现它(UserManager, d^"<Tz!
ln#Jb&u
UserManagerImpl) DGMvYNKTj
java代码: %UuV^C
XOQj?Q7)U
+~Ni7Dp]
/*Created on 2005-7-15*/ Hf( d x\5
package com.adt.service; _Y'+E
kK2x';21
import net.sf.hibernate.HibernateException; &u-H/CU%
JHpaDy*
import org.flyware.util.page.Page; T!.6@g`x>
%/17K2g
import com.adt.bo.Result; Yb8o`j+t
[bd fp
a
/** X p4x:N
* @author Joa tL68
u[
*/ U$R+&@;
publicinterface UserManager { './j<2|;U
`a}!t=~#w
public Result listUser(Page page)throws lg_X|yhL
0*S2_&Q)
HibernateException; gbOd(ugH
bKsl'3~ k
} .l$'%AG:~
dALJlRo"
$gm`}3C<
%zx=rn(K
ek~bXy{O`
java代码: lYkm1
;W6P$@'zs
?[>+'6
/*Created on 2005-7-15*/ wykk</eQ.i
package com.adt.service.impl; -=aI!7*"$
*k:Sg*neVq
import java.util.List; RX.n7Tb
trL:qD+{(
import net.sf.hibernate.HibernateException; UTw f!
HMbF#!E
import org.flyware.util.page.Page; V3O<l}ak
import org.flyware.util.page.PageUtil; D&q-L[tA@
X(F2 5
import com.adt.bo.Result; W]p)}#FR
import com.adt.dao.UserDAO; 0\f3L a
import com.adt.exception.ObjectNotFoundException; Vt-D8J\A
0
import com.adt.service.UserManager; kIS_6!
$
BV4 i$
/** :hYV\8$
* @author Joa hO3>Gl5<
*/ z_vFf0
publicclass UserManagerImpl implements UserManager { %jKbRiz1u
$ qk2!
private UserDAO userDAO; 2
F3U,}
T0xU}
/** *C*n (the
* @param userDAO The userDAO to set. J1kG'cH05
*/ )8Defuxk
publicvoid setUserDAO(UserDAO userDAO){ +~lZ]a7k
this.userDAO = userDAO; i9?$BZQ[R
} (rV#EA+6[`
aW-'Jg=@H^
/* (non-Javadoc) Bi?+e~R
* @see com.adt.service.UserManager#listUser Id3i qAL
CO!K[q#
(org.flyware.util.page.Page) k^-HY[Q9
*/ jRP.Je@t
public Result listUser(Page page)throws ;`IZ&m$
c`
^I% i
HibernateException, ObjectNotFoundException { rJ)O(
int totalRecords = userDAO.getUserCount(); )N!-g47o%#
if(totalRecords == 0) ]Z?$ 5Ks
throw new ObjectNotFoundException ~3bn?'`
Jsf-t
("userNotExist"); :e1BQj`R
page = PageUtil.createPage(page, totalRecords); $CXKeWS=Q.
List users = userDAO.getUserByPage(page); uY+N163i
returnnew Result(page, users); NMYkEz(&R
} p3Uus''V4
s,UccA@
} cTf/B=yMi
~Ti
"I.PV$Rxl
M$j]VZ
yM(zc/?
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >,22@4
<t[WHDO`
询,接下来编写UserDAO的代码: S'"(zc3=
3. UserDAO 和 UserDAOImpl: __jFSa`at
java代码: L7i^?40
L=zt\L
e>W}3H5w0
/*Created on 2005-7-15*/ zRDBl02v$T
package com.adt.dao; ^DZ(T+q,
#?h#R5:0
import java.util.List; =bm<>h7.)
{bB;TO<b`
import org.flyware.util.page.Page; lTOO`g
S7SD$+fX
import net.sf.hibernate.HibernateException; $agd9z,&m
noz&4"S.{
/** @m14x}H
* @author Joa ki`7S
*/ "Xq.b"N{*
publicinterface UserDAO extends BaseDAO { z Qtg]@S
yj!4L&A
publicList getUserByName(String name)throws 595P04
J6 }J /
HibernateException; 'Dl31w%:
bbevy!m
publicint getUserCount()throws HibernateException; {1
fva^O
qH(3Z^ #.|
publicList getUserByPage(Page page)throws 871taL=
J{Fu 8
HibernateException; r|[uR$|Y
(xnXM}M&2Y
} e-vwve
tjw4.L<r
h"<-^=b
5"1kfB3v
G2Zr(b')
java代码: Ms8&$
-ZXC^zt
x O`#a=
/*Created on 2005-7-15*/ UR;FW`
package com.adt.dao.impl; R<>ptwy
Ph(bgQg
import java.util.List; % j4
&HdzbKO=
import org.flyware.util.page.Page; I8=p_Ie
Si[:l
import net.sf.hibernate.HibernateException; FF]xwptrx
import net.sf.hibernate.Query; -z"=d<@
tY=sl_
import com.adt.dao.UserDAO; U#3Y3EdF<
gp
Aqz Y
/** O=c^Ak
* @author Joa 8P8@i+[]W
*/ lFMQT
;
public class UserDAOImpl extends BaseDAOHibernateImpl @SA:64
9
"/v{B?~%!
implements UserDAO { ~4HS
2\
*z-Mr~V
/* (non-Javadoc) `/en&l
* @see com.adt.dao.UserDAO#getUserByName -X#Zn>#
.6I*=qv)NA
(java.lang.String) L[4Su;D
*/ Ji<^s@8Zc
publicList getUserByName(String name)throws LIM
cZh ;
o5(`7XV6D
HibernateException { tE"aNA#=
String querySentence = "FROM user in class X"yjsk
1an?/j,
com.adt.po.User WHERE user.name=:name"; s&-m!|P
Query query = getSession().createQuery tz0_S7h
q.]>uBAQ?
(querySentence); y^"[^+F3 .
query.setParameter("name", name); r=8(n<;Co
return query.list(); V[&4Km9C
} t#pF.!9=
x[]}Jf{t
/* (non-Javadoc) (+Ia:D
* @see com.adt.dao.UserDAO#getUserCount() D@5Ud)_
*/ ,dhSc<:LT
publicint getUserCount()throws HibernateException { i}C9
int count = 0; hq}kAv4B=
String querySentence = "SELECT count(*) FROM >0yx!Iao
V-Ebi^gz5W
user in class com.adt.po.User"; # fvt:iE
Query query = getSession().createQuery 7]}n0*fe
\nQV{J
(querySentence); l (;~9u0sa
count = ((Integer)query.iterate().next q'u^v PO
VFUuG3p)
()).intValue(); N 2|?I(\B
return count; *`]LbS
} EjZ_|Q
bDh,r!I
/* (non-Javadoc) :q6j{C(
* @see com.adt.dao.UserDAO#getUserByPage kjWY{7b!
~&bn}
M>W
(org.flyware.util.page.Page) FbxrBM
*/ 3f;W+^NY
publicList getUserByPage(Page page)throws Jb.
V4
.L;M-`^
HibernateException { )HPt(Ck
String querySentence = "FROM user in class O6nCu
[T 8BQn!
com.adt.po.User"; [ 0?*J<d
Query query = getSession().createQuery :by EXe;3
#=~n>qn]
(querySentence); gmG
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query.setFirstResult(page.getBeginIndex()) =pQ'wx|>|
.setMaxResults(page.getEveryPage()); Uy8r
!9O
return query.list(); {FV_APL9_
} Ja$Ple*XU8
k%UE^
} //9M~qHa"
M'Ec:p=X"
d@o1<Q
`~${fs{-`/
/yRP>CX~
至此,一个完整的分页程序完成。前台的只需要调用 >hg?!jMjrr
t[L0kF9en
userManager.listUser(page)即可得到一个Page对象和结果集对象 Yvky=RM
:Iy4B+
的综合体,而传入的参数page对象则可以由前台传入,如果用 07L
>@Gf
Qx$CoY
webwork,甚至可以直接在配置文件中指定。 R $vo
lFHj]%Y
下面给出一个webwork调用示例: {rp5qgVE<
java代码: :el]IH
{*EA5;
#
tN#_<W
/*Created on 2005-6-17*/ Q>`|{m
package com.adt.action.user; 8t{-
6pyLb3[e
import java.util.List; Q};g~b3
u;{,,ct
import org.apache.commons.logging.Log; .<GU2&;!
import org.apache.commons.logging.LogFactory; sn.Xvk%75
import org.flyware.util.page.Page; mGf@J6wGz
:nk $?5ib
import com.adt.bo.Result; u19d!#g
import com.adt.service.UserService; 7#\\Ava$T
import com.opensymphony.xwork.Action; 51:NL[[6
|VlQ0{
/** nYfZ[Q>v
* @author Joa LP_w6fjT
*/ )~(( 6?k4e
publicclass ListUser implementsAction{ xp+Z%0D
(`z`ni
privatestaticfinal Log logger = LogFactory.getLog nq9|cS%-
}jF67c->
(ListUser.class); 8Ja't8
D;~c`G
"f
private UserService userService;
4d\1W?i-
:%&~/@B
private Page page; 'IR2H{Q
:i;iSrKy
privateList users; e -sZ_<GH
Wn p\yx`
/* V/
a!&_""
* (non-Javadoc) irg%n
* e;IzK]kP
* @see com.opensymphony.xwork.Action#execute() <{
Z$!]i1
*/ \YV`M3O
publicString execute()throwsException{ cr;\;Ta_!W
Result result = userService.listUser(page); xPuuG{Sm
page = result.getPage(); ]{mz %\
users = result.getContent(); !F@9xG
return SUCCESS; 5e> <i
} !G`7T
e.8(tEqZ1
/** ]`p*ZTr)\
* @return Returns the page. ^U[c:Rz
*/ /hx|KC&:e
public Page getPage(){ '?WKKYD7N
return page; jHP6d =
} +7HM7cw
+W{ELdup%q
/** "JHdF&
* @return Returns the users. WfnBWSA2T
*/ 5*Wo/%#q
publicList getUsers(){ d nZA+Pa
return users; y.pwj~s
} ]<9KX} B
TB!z:n
/** _[eAA4h
* @param page ;r**`O
* The page to set. ,-55*Rb i
*/ !|SVRaS
publicvoid setPage(Page page){ nhbCk6Y5LZ
this.page = page; WyO7,Qr\
} 0N" VOEvG
DH3.4EUWS
/** :P!"'&gCL
* @param users 7U:-zfq
* The users to set. O@[jNs)].
*/ F@+FXnz
publicvoid setUsers(List users){ {
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this.users = users; tH7@oV;
} 7Nw}
}
v>e%5[F
/** }ZP;kM$g
* @param userService A7|CG[wZ
* The userService to set. BCrX>Pp}r
*/ F4Jc7k2
publicvoid setUserService(UserService userService){ !uoQLiH+
this.userService = userService; zvzS$Gpe
} $]{20"
} &zGf`Zi6*%
Nb[zm|.
aGl*h"&
I UMt^z
^rHG#^hA
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, `|{6U"n
{giKC)!
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 3G4N0{i
\.@fAgv
么只需要: ^oL43#Nlo
java代码: `{1&*4!
PT`];C(he
X^2Txm d
<?xml version="1.0"?> E3p3DM0F$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork u]D>O$_ s
Sqc
r
-
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ?Aewp$Bj
Ezvm5~<
1.0.dtd"> xaM?
B7
o@p(8=x
<xwork> PYOU=R%o`8
zK*zT$<l
<package name="user" extends="webwork- `|t X[':
a!_vd B
interceptors"> b1("(,r/`
<c,/+
lQ^
<!-- The default interceptor stack name .e^AS~4pl
( %i)A$i6a
--> c
h_1-
<default-interceptor-ref u{H'evv0O
=p1aF/1$I
name="myDefaultWebStack"/> zF%'~S0{
Ql%0%naq1
<action name="listUser" h{$mL#J
Vy+%sG
q"
class="com.adt.action.user.ListUser"> *KDT0 ;/s
<param "agc*o~!F
[f_4%Now
name="page.everyPage">10</param> rh8.kW-K_
<result Bi!j re
j K!Y-
name="success">/user/user_list.jsp</result> B@:11,.7
</action> [RZ}9`V
)Mtw9[
</package> UL46%MFQ\
0+i\j`O&
</xwork> kLr6j-X
Q%seV<!/
nJdO~0}3
gypE~@
TAkM-iyH]
^/)!)=?
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 l7.W2mg
Eyv|~D
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。 x[ sSM:
K2W$I H:.
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 =:|fN3nJ2
!hBzT7CO
__FhuP P
:;wb{q$O
!Q`vOVSUD
我写的一个用于分页的类,用了泛型了,hoho z_Nw%V4kr
+cDz`)N,,
java代码: ^kS44pr\Q
R)%1GG4
yf2I%\p}
package com.intokr.util; 5i 6*$#OM_
K*ZH<@o4
import java.util.List; g _2m["6*
)2U#<v^
/** @iW^OVpp<8
* 用于分页的类<br> WWO@ULGY
* 可以用于传递查询的结果也可以用于传送查询的参数<br> !A. Kb74
* ]h
Dy]
* @version 0.01 b),_rr
* @author cheng F(-1m A&-
*/ S`!MoIMsD
public class Paginator<E> { 6Y#V;/gK!5
privateint count = 0; // 总记录数 \Oku<5
privateint p = 1; // 页编号 ]^>#?yEA3
privateint num = 20; // 每页的记录数 efK)6T^p
privateList<E> results = null; // 结果 /,>@+^ 1
~-"<)XPe
/** >%~E <
* 结果总数 +2}aCoL\
*/ 2MNAY%iT
publicint getCount(){ 0(uNFyIG
return count; xk1pZQ8c
} DwQaj"1<%
vd4}b>
publicvoid setCount(int count){ J!%cHqR
this.count = count; m[@7!.0=
} [7QIpt+FSo
M5SAlj
/** ~MvLrg"i
* 本结果所在的页码,从1开始 `OY_v=}
* 7[V6@K!Al[
* @return Returns the pageNo. B{D!5{t
*/ ~[J&n-bJU
publicint getP(){ "hwG"3n1
return p; B!Ss
35<
} ;'\{T#5)
*mqoyOa
/** >3S^9{d
* if(p<=0) p=1 QU&b5!;&
* fP>K!@!8
* @param p YWfw%p?n"
*/ 7VP[U,
publicvoid setP(int p){ ]"Do%<