Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ]-q:Z4rb
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^X?[zc GE
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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 qaQ
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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@*Z@]FC
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分页支持类: ^8\pJg_0
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java代码: `W/6xm(X5;
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package com.javaeye.common.util; mHhm~u
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import java.util.List; {!="PnB
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publicclass PaginationSupport { I?:V EN:
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publicfinalstaticint PAGESIZE = 30; k{;:KW|
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privateint pageSize = PAGESIZE; zZy>XHR
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privateList items; vD*KJ3(c
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privateint totalCount; H4pjtVBr
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privateint[] indexes = newint[0]; ~ 7k
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privateint startIndex = 0; *"4ltWS
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public PaginationSupport(List items, int d`xqs,0f
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totalCount){ Z,2uN!6
setPageSize(PAGESIZE); (thzWr6;
setTotalCount(totalCount); `?>OY&(
setItems(items); 9 (&!>z
setStartIndex(0); kfHLjr.
} Oll\T GXP!
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public PaginationSupport(List items, int Zw3|HV(so
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totalCount, int startIndex){ cEN^H
setPageSize(PAGESIZE); Z]6D0b
setTotalCount(totalCount); oDRNM^gz
setItems(items); }`eeIt I+
setStartIndex(startIndex);
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} 57#:GN$EL
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public PaginationSupport(List items, int @!Pq"/
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totalCount, int pageSize, int startIndex){ z6Hl+nq B
setPageSize(pageSize); #a0 (Wh7
setTotalCount(totalCount); /RMep8&
setItems(items); "#OmmU<U
setStartIndex(startIndex); yf$7<gwX
} fL@[B{XMM
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publicList getItems(){ t EN%mK
return items; 5n"'M&Ce
} oo qNPLa
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publicvoid setItems(List items){ h?SUDk:2^
this.items = items; d9^h
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} `Ffn:=Do
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publicint getPageSize(){ mT9TSW}
return pageSize; R{WG>c
} $`riB$v
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publicvoid setPageSize(int pageSize){ ](O!6_'d
this.pageSize = pageSize; 0 8U:{LL
} 7<)
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publicint getTotalCount(){ 6Y=$7%z
return totalCount; ycH=L8
} :xA'X+d/'
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publicvoid setTotalCount(int totalCount){ cL}g7D
if(totalCount > 0){ {:"bX~<^
this.totalCount = totalCount; d)
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int count = totalCount / tV T(!&(
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pageSize; phNv^R+
if(totalCount % pageSize > 0) J4JKAv~3
count++; Hu;#uAnxQ
indexes = newint[count]; [bZXzV(
for(int i = 0; i < count; i++){ ruA!+@or
indexes = pageSize * S4\T (
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} ge E7<"m%
}else{ '91Ak,cWB
this.totalCount = 0; 9\dC8
} HWc=.Qq
} 8'f:7KF
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publicint[] getIndexes(){ +DU}f;O8v
return indexes; 8J@REP4
} EJRwyF5LK
~< k'{
publicvoid setIndexes(int[] indexes){ 8J>s|MZ
this.indexes = indexes; {!<zk+h$
} 3n,F5?!m
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publicint getStartIndex(){ 9 Z4H5!:(
return startIndex; ;Neld #%J
} PsTwJLY
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publicvoid setStartIndex(int startIndex){ <8'}H`w%
if(totalCount <= 0) l.&6|
this.startIndex = 0; 0uj3kr?cv
elseif(startIndex >= totalCount) k<AnTboa
this.startIndex = indexes WyO10yvR
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[indexes.length - 1]; v_b%2;<1
elseif(startIndex < 0) OpiN,>;
this.startIndex = 0; **oN/5
else{ Bf8 #&]O
this.startIndex = indexes a*o=,!
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[startIndex / pageSize]; g4U%(3,>D
} zHyM@*Gf(
} [t>}M6?R:
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publicint getNextIndex(){ .)Du
;
int nextIndex = getStartIndex() + &'i>5Y
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pageSize; /9i2@#J}W1
if(nextIndex >= totalCount) 38rC;
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return getStartIndex(); ?*Jv&f#
else N 0`)WLW
return nextIndex; 2'N%KKmJL
} [X;yJ $
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publicint getPreviousIndex(){ sN;xHTY
int previousIndex = getStartIndex() - \QQw1c+
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pageSize; N5o jXX!l%
if(previousIndex < 0) 0<fN<iR`
return0; meE&, {
else z#*fELV
return previousIndex; EdLbVrN,
} kJ{X5&,_
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} p'!cGJL
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抽象业务类 EW|bs#l
java代码: QYDSE
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/** gP?pfFhG
* Created on 2005-7-12 }5u$/c@f1
*/ :<!a.%=
package com.javaeye.common.business; vDqmD{%4N
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import java.io.Serializable; M2{{B^*$6
import java.util.List; '
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import org.hibernate.Criteria; oBpHmMzA
import org.hibernate.HibernateException; 4Y;z46yM%
import org.hibernate.Session; ,A4v|]kq]
import org.hibernate.criterion.DetachedCriteria; 0M>+.}e+
import org.hibernate.criterion.Projections; ]*D=^kA0[
import bU7n1pzW,o
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org.springframework.orm.hibernate3.HibernateCallback; Jt^a
import ;3'ta!.c
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org.springframework.orm.hibernate3.support.HibernateDaoS lmfvT}$B
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upport; z;J"3kM
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import com.javaeye.common.util.PaginationSupport; A_i=hj2f
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public abstract class AbstractManager extends 'H0uvvhOp
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HibernateDaoSupport { )w4i0Xw^C:
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privateboolean cacheQueries = false; \C#XKk$OE
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privateString queryCacheRegion; ]ri5mnB
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publicvoid setCacheQueries(boolean N2#Wyt8MC
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cacheQueries){ ~=67#&(R
this.cacheQueries = cacheQueries; *eK\W00
} "wy|gnQJ
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publicvoid setQueryCacheRegion(String K&3,J7&&
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queryCacheRegion){ 8iA[w-Pv
this.queryCacheRegion = }OL?k/w
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queryCacheRegion; UuPXo66F]
} L7VD ZCV
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publicvoid save(finalObject entity){ ])`w_y(>
getHibernateTemplate().save(entity); 5$$ Yce=k
} ]{^'{ z$i
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publicvoid persist(finalObject entity){ 42]hX9E
getHibernateTemplate().save(entity); T+1:[bqK
} xq$(=WPI
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publicvoid update(finalObject entity){ >xsbXQ>.
getHibernateTemplate().update(entity); 41Ga- 0p
} o^+2%S`]
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publicvoid delete(finalObject entity){ +Np[m$Z*
getHibernateTemplate().delete(entity); MkLXMwuQ&
} kD;1+lNz
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publicObject load(finalClass entity, Cw$0XyO
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finalSerializable id){ `xv2,Z9<
return getHibernateTemplate().load UI2TW)^2
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(entity, id); MD|T4PPz,}
} Z uFk}R"x
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publicObject get(finalClass entity, 7qsu0 .[d
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finalSerializable id){ w.X MyHj
return getHibernateTemplate().get (w[#h9j
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(entity, id); yzyBr1s
} 27J!oin$
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publicList findAll(finalClass entity){ ?qC6p|H
return getHibernateTemplate().find("from vbBNXy/
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" + entity.getName()); NVnId p
} L!;"73,&(8
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publicList findByNamedQuery(finalString 05>mR qVL
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namedQuery){ f4 k
return getHibernateTemplate e'I/}J
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().findByNamedQuery(namedQuery); ~F"<N q
} a_Sp}s<J
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publicList findByNamedQuery(finalString query, U_Jchi,!
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finalObject parameter){ Jn7T5$pJ
return getHibernateTemplate #B2a?
r{ >`"
().findByNamedQuery(query, parameter); `uP:UQ9S
} 2x5^kN7
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publicList findByNamedQuery(finalString query, z`}z7e'>
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finalObject[] parameters){ r=Tz++!
return getHibernateTemplate #Mw 6>5}<
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().findByNamedQuery(query, parameters); I=[Ir8};
} 9| g]M:{
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publicList find(finalString query){ l*>,K2F
return getHibernateTemplate().find @>fsg-|
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(query); '\O[j*h^.
} hv0bs8h
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publicList find(finalString query, finalObject dy>5LzqK3
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parameter){ :
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return getHibernateTemplate().find 38GkV.e}$
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(query, parameter); O=[Q>\p
} J Bgq2
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public PaginationSupport findPageByCriteria [I?[N.v
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(final DetachedCriteria detachedCriteria){ 9])Id;+91
return findPageByCriteria ,<=gPs;x
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); r.q*S4IS.m
} Qz"+M+~%&
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public PaginationSupport findPageByCriteria ^sKdN-{
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(final DetachedCriteria detachedCriteria, finalint `# U<'$
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startIndex){ KpBOmXE
return findPageByCriteria 5e3p9K`5
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(detachedCriteria, PaginationSupport.PAGESIZE, z:a7)z
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startIndex); Kf-XL),3l
} G} f9:G
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public PaginationSupport findPageByCriteria tQ*?L
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(final DetachedCriteria detachedCriteria, finalint Ay7PU
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pageSize, /X]gm\x7s
finalint startIndex){ uO>x"D5tZ:
return(PaginationSupport) 7Ll?#eun
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getHibernateTemplate().execute(new HibernateCallback(){ #<~oR5ddlb
publicObject doInHibernate *>/w,E]
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(Session session)throws HibernateException { H u9nJ
Criteria criteria = <0VC`+p<)
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detachedCriteria.getExecutableCriteria(session); ch2m Ei(
int totalCount = +DG-MM%\
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((Integer) criteria.setProjection(Projections.rowCount mGDy3R90
E-%$1=;
()).uniqueResult()).intValue(); R$!]z(
criteria.setProjection [+d~He
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(null); ;m7~!m)
List items = {qGXv@
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criteria.setFirstResult(startIndex).setMaxResults k`#E#1niN
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(pageSize).list(); _&(L{cFx6
PaginationSupport ps = IL:[0q
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new PaginationSupport(items, totalCount, pageSize, a~ RY 8s
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startIndex); u -)ED
return ps; fWPa1E@
} *s#6e}
}, true); ?H!jKX
} k.7!)jL7
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public List findAllByCriteria(final *<:6A&'D9
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DetachedCriteria detachedCriteria){ zB`J+r;LU
return(List) getHibernateTemplate ^rs{1S
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().execute(new HibernateCallback(){ mU(v9Jpf7
publicObject doInHibernate rizjH+
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(Session session)throws HibernateException { 6ddRFpe
Criteria criteria = bo/<3gR
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detachedCriteria.getExecutableCriteria(session); 7IFZK\V
return criteria.list(); wpp!H<')
} TQ:h[6v
}, true); H
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} KWeE!f 7G
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public int getCountByCriteria(final s Pb}A$'
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DetachedCriteria detachedCriteria){ 1;KJUf[N
Integer count = (Integer) iITMBS`}
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getHibernateTemplate().execute(new HibernateCallback(){ ~%lA!tsek
publicObject doInHibernate C~ A`h=A<
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(Session session)throws HibernateException { #'},/Lm@
Criteria criteria = (&87 zk
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detachedCriteria.getExecutableCriteria(session); `\|@w@f|;
return Nmd{C(^o
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criteria.setProjection(Projections.rowCount Z"'*A\r2
}A]eC
()).uniqueResult(); #>HY+ ;
} d2NFdBoI
}, true); j/Y]3RSMp
return count.intValue(); `mW~ {)x
} @U3z@v]s(h
} 3=o4ncg(
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用户在web层构造查询条件detachedCriteria,和可选的 w N`Njm9!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 r~JGs?GH
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PaginationSupport的实例ps。 7QnWw0
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ps.getItems()得到已分页好的结果集 eub}+~_?[
ps.getIndexes()得到分页索引的数组 O9- `e
ps.getTotalCount()得到总结果数 aeI0;u
ps.getStartIndex()当前分页索引 \2=I//YF
ps.getNextIndex()下一页索引 0:71Xm
ps.getPreviousIndex()上一页索引 0:n"A,-p
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 'K02T:\iZ
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ^fe,A=k~1
f8SO:ihXL
一下代码重构了。 |c8\alw
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我把原本我的做法也提供出来供大家讨论吧: rM,f7hm[S*
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首先,为了实现分页查询,我封装了一个Page类: AX%}ip[PC
java代码: ,52Lm=n
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/*Created on 2005-4-14*/ `L 1+j
package org.flyware.util.page; gE$Uv*Gj
*k; bkd4x
/** +6l#hO7h
* @author Joa z/h]Jos
* ,u^{zYoW
*/ rv(N0p/
publicclass Page { 9B;WjXSe
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/** imply if the page has previous page */ n*ShYsc
privateboolean hasPrePage; 3) d}3w {
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/** imply if the page has next page */ n{<}<SVY
privateboolean hasNextPage; L fcy#3!
IDJ2epW*;
/** the number of every page */ ^X+qut+~
privateint everyPage; n"aF#HR?0d
gm,AH85
/** the total page number */ ubfh4
privateint totalPage; ^^7@khmNl
7S
8X)
/** the number of current page */ 0>BI[x@
privateint currentPage; $#+D:W)az
S>h\D4.
/** the begin index of the records by the current 8x)i{>#i
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query */ .%7Le|Fb"
privateint beginIndex; Z2yO /$<
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/** The default constructor */ H"^9g3U
public Page(){ 6,jCO@!
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} gJuK% P
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/** construct the page by everyPage 1U.X[}e
* @param everyPage m:`M&Xs&
* */ - E GZ
public Page(int everyPage){ M^8zqAA
this.everyPage = everyPage; {wA8!5Gu
} k7rg:P
,D*bLXWh
/** The whole constructor */ <yX u!
public Page(boolean hasPrePage, boolean hasNextPage, [^ r8P:Ad
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int everyPage, int totalPage, Y DHP-0?
int currentPage, int beginIndex){ HyWR&0J
this.hasPrePage = hasPrePage; '" %0UflJS
this.hasNextPage = hasNextPage; <`=Kt[_BQ
this.everyPage = everyPage; VVAc bAGJ
this.totalPage = totalPage; UCmy$aW
this.currentPage = currentPage; -Z:x!M[Xr
this.beginIndex = beginIndex; vX6JjE!
} gsEcvkj*
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/** \ +sa[jK
* @return ;A@DE@^5w
* Returns the beginIndex. (M1YOK) I
*/ {V(~
publicint getBeginIndex(){ "5k6FV
return beginIndex; o938!jML_
} \W TKw x
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/** (!5Pl`:j"
* @param beginIndex 1;c># 20
* The beginIndex to set. C{^I}p
*/ |;~2y>E
publicvoid setBeginIndex(int beginIndex){ fPKpV`Hr3
this.beginIndex = beginIndex; U`EOun,
} _+aR|AEC
'{.4~:
/** @ewi96
* @return
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* Returns the currentPage. 1;<Vr<.
*/ x+za6e_k"
publicint getCurrentPage(){ Rrry;Hr
return currentPage; :w5g!G?z
} ^?(#%~NS
'v0rnIsI?
/** T }msF
* @param currentPage $'5rS$]a/
* The currentPage to set. ;a@riPqx!
*/ p.8
publicvoid setCurrentPage(int currentPage){ !lFNG:&`
this.currentPage = currentPage; `i(b%$|^&Z
} @J5TDq @
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/** ak_y:O|
* @return /%,aX[
* Returns the everyPage. s:xJ }Ll
*/ ke;=Vg|
publicint getEveryPage(){ c;"e&tW
return everyPage; KFO
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} eHs38X
x"C7NW[$
/** %>9L}OAm
* @param everyPage [QQM/ ?
* The everyPage to set. `S-l.zSZ4B
*/ hg0{x/Dgny
publicvoid setEveryPage(int everyPage){ d`flYNg4
this.everyPage = everyPage;
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} .xT{Rz
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/** t>N2K-8Qh
* @return S _U |w9q
* Returns the hasNextPage. 8LPWT! S
*/ u
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publicboolean getHasNextPage(){ n CX{tqy
return hasNextPage; eXnSH$uI
} ..nVViZ
wy:Gy9\
/** (2Lmu[
* @param hasNextPage 3o>JJJ=]
* The hasNextPage to set. wL:7G
*/ g|3bM
publicvoid setHasNextPage(boolean hasNextPage){ ']\SX*z?
this.hasNextPage = hasNextPage; 0',buJncV
} %vZHHBylu
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/** <N~9=g3
* @return F Xr\
* Returns the hasPrePage. T!9AEG
*/ B?^~1Ua9Zv
publicboolean getHasPrePage(){ J;wBS w%1
return hasPrePage; >2),HZp^I
} P=<lY},
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/** #7'k'(
* @param hasPrePage y O@1#
* The hasPrePage to set. m6K7D([f
*/ 8`)* ?Q9~
publicvoid setHasPrePage(boolean hasPrePage){ k+"7hf=C|
this.hasPrePage = hasPrePage; Gukvd6-g9b
} hPz=Ec<zW
xgkCN$zQ`
/** y*sVimx
* @return Returns the totalPage. pnp8`\cIH
* M"p%CbcI]
*/ C_q2bI
publicint getTotalPage(){ oO3^9?Z
return totalPage; $]};EI#
} SKNHLE}
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/** kjsj~jwvv
* @param totalPage -
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* The totalPage to set. k1yqerA
*/ IOC$jab@
publicvoid setTotalPage(int totalPage){ `5Z'8^
this.totalPage = totalPage; ,38M6yD
} 3$P
}TZM@{;
} gk?H@b*
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 9yTDuhJ6
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个PageUtil,负责对Page对象进行构造: NCzabl
java代码: @@\px66
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/*Created on 2005-4-14*/ [hot,\+f
package org.flyware.util.page; V"K.s2U^
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import org.apache.commons.logging.Log; |unvDXx-
import org.apache.commons.logging.LogFactory; ,/V~T<FI
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/** adri02C/
* @author Joa baTd;`Pn
* lg
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*/ WEG!;XZ
publicclass PageUtil { %rlqq*
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privatestaticfinal Log logger = LogFactory.getLog ARnq~E@1
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(PageUtil.class); u^^jt(j
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/** Lh-Y5(c
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* Use the origin page to create a new page SCMvq?9
* @param page %q;y74
* @param totalRecords )
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* @return daSx^/$R
*/ u^]Gc p
publicstatic Page createPage(Page page, int W]bytsl
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totalRecords){ ~~"U[G1
return createPage(page.getEveryPage(), 9+<A7PM1T
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page.getCurrentPage(), totalRecords); `S?_=JIX
} !h}Vz
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/** y,jpd#Y
* the basic page utils not including exception D8E^[w!
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handler *M`,#
* @param everyPage Si23w'T
* @param currentPage T\4>4eX-
* @param totalRecords _^RN$4.R>
* @return page G#NbLj`h
*/ v5?)J91
publicstatic Page createPage(int everyPage, int KkzG#'I1
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currentPage, int totalRecords){ &"A:_5AU
everyPage = getEveryPage(everyPage); zd$iDi($
currentPage = getCurrentPage(currentPage); In:V.'D/>t
int beginIndex = getBeginIndex(everyPage, {`)oxzR
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currentPage); 5oB#{h
int totalPage = getTotalPage(everyPage, pV:44
4XiQ8"C
totalRecords); %Y#W#G
boolean hasNextPage = hasNextPage(currentPage, q`z1ht
nf
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totalPage); N;}X$b5Y @
boolean hasPrePage = hasPrePage(currentPage); ~K|ha26W
bYhG`1,$-a
returnnew Page(hasPrePage, hasNextPage, Y![i=/
everyPage, totalPage, N 5{w
currentPage, \>.[QQVI"l
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beginIndex); )`W|J%w+
} MX!N?k#KhP
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privatestaticint getEveryPage(int everyPage){ #\xy,C'Y
return everyPage == 0 ? 10 : everyPage; 4v5qK
} SjA'<ZX>TM
QiVKaBS8
privatestaticint getCurrentPage(int currentPage){ u~'_Uqp
return currentPage == 0 ? 1 : currentPage; ,}>b\(Lk
} \>j@!W
UIIsgNca
privatestaticint getBeginIndex(int everyPage, int ]*)l_mut7
CSWA/#&8>
currentPage){ ZN'B@E=p
return(currentPage - 1) * everyPage; # M3d =
} #X{lV]Z
[(8s\>T
privatestaticint getTotalPage(int everyPage, int <5FGL96
CL(D&8v8~
totalRecords){ C\bJ_vl;'
int totalPage = 0; mB
bGj3u;
mL;oR4{
if(totalRecords % everyPage == 0) ,]9p&xu
totalPage = totalRecords / everyPage; 4/S3hH
else mmNn,>AO!
totalPage = totalRecords / everyPage + 1 ; pA@R,O>zr
rT4q x2 u
return totalPage; 1[a#blL6W
} *9F{+)A
\qG` ts
privatestaticboolean hasPrePage(int currentPage){ CA$|3m9)NM
return currentPage == 1 ? false : true; X6r<#n|l
} zY4y]k8D*
Fy6Lz.baB
privatestaticboolean hasNextPage(int currentPage, 7}&vEc@w&
_a`/{M|
int totalPage){ ~@}n}aV'!
return currentPage == totalPage || totalPage == @qA11C.hq
pVjOp~=U
0 ? false : true; pd.pY*B<[
} tgeXX1Eq!
{irl}EeyC
bi-z%!Z
} ~Hx>yn94e
KYg'=({x
Kj4L PG
vr
kj4Jf
i~4$V
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。 >oAXS\Ts
Q+U" %
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 SU~ljAF4
{G|= pM\'
做法如下: H:16aaMn(
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 6mIRa(6V
f{(D+7e}
的信息,和一个结果集List: <hgfgk7<
java代码: }tH_YF}u
zx?|5=+!
.=Uu{F
/*Created on 2005-6-13*/ uF
D
package com.adt.bo; >ca`0gu
S1i~r+jf
import java.util.List; @'J[T: e
h}oV)z6
import org.flyware.util.page.Page; %;GRR (K
#Qu|9Q[QH
/** N=!k2+
* @author Joa T{'oR .g,
*/ G{a_\'7
publicclass Result { es$<Vkbp
|Ur$H!oe?'
private Page page; ]<_v;Q<t
@]V_%,
private List content; Orlf5{P
Cv`dK=n>
/** R?2T0^0
* The default constructor iYr*0:M
*/ 6D*x5L-1o
public Result(){ WBD"d<>'
super(); > IZ$ .-
} `n`HwDo;i
,!^;<UR:
/** -e+im(2D=
* The constructor using fields {]7lh#M
* 7;sF0oB5e
* @param page ^|cax|>
* @param content EM'#'fBZ>Y
*/ ;T>.
public Result(Page page, List content){ \LM{.gzT
this.page = page; .;:dG
this.content = content; J
p0j
} T&E'MB
Z?."cuTt
/** +OOmy
* @return Returns the content. U)('}u=b
*/ ofCN[u
publicList getContent(){ pE G!j ~
return content; Tx$bg(
} ,@8*c0Y~<!
aq^OzKP?
/** m9$lOk4/
* @return Returns the page. % )}rQqQ
*/ (/_w23rr
public Page getPage(){ [](] "r
return page; /jn0Xh
} [Lid%2O3ZR
9_%??@^>
/** i6:O9Km
* @param content 7{OD/*|
* The content to set. a#/~rNRY
*/ 6lQP+! EF
public void setContent(List content){ RJD(c#r$
this.content = content; ooN?x31
} mP./e8
m*>gG{3;
/** }FkF1?C
* @param page :-T[)Q+-3
* The page to set. +,4u1`c|$
*/ nS^,Sq\Ak
publicvoid setPage(Page page){ QM=Y}
this.page = page; '#612iZo
} 6J3<k(#:
} 'u:J
"
8+&Da
D[K!xq
edfb7prfTl
mfgUf
2. 编写业务逻辑接口,并实现它(UserManager, 7hKfxw-X@
SJ&+"S&
UserManagerImpl) S@WT;Q2Z
java代码: z3|5E#m
`t]8 [P5
Lr(My3vF8q
/*Created on 2005-7-15*/ *V@t]d$=#
package com.adt.service; E
qt\It9
3s,a%GOk
import net.sf.hibernate.HibernateException; FOSC#W9E
BvpUcICJ
import org.flyware.util.page.Page; 0gJ{fcI
eeOG(@@o(
import com.adt.bo.Result; M4L<u,\1s
yOm#c>X
/** sbq:8P#
* @author Joa ?#/~BZR!
*/ tr%VYc|}
publicinterface UserManager { "0?"
E\
207h$a,
public Result listUser(Page page)throws 6oq/\D$6~
|h2=9\:]
HibernateException; 81S0: =
L&Pj0K-HT3
} -dH]_
V`"Cd?R0Z
d+IN-lR(
0@}:`OynX
<*db%{
java代码: `s_k+ g
HurF4IsHk
nMH:7[x3
/*Created on 2005-7-15*/ ;^so;>F
package com.adt.service.impl; 8MBvp*
?l](RI
import java.util.List; S1_):JvV
a}kPc}n\
import net.sf.hibernate.HibernateException; 3q0S}<h al
#i-b|J+%
import org.flyware.util.page.Page; X;yThb`iI
import org.flyware.util.page.PageUtil; SM[VHNr,-
lxtt+R
import com.adt.bo.Result; &nwk]+,0W#
import com.adt.dao.UserDAO; vH>s2\V"
import com.adt.exception.ObjectNotFoundException; wI#R\v8(`n
import com.adt.service.UserManager; .;%`I
Gs(;&fw
/** /*m6-DC
* @author Joa (*V:{_r
*/ H:,Hr_;nC
publicclass UserManagerImpl implements UserManager { FLaj|Z~#)
wRe2sjM
private UserDAO userDAO; Ca#T?HL
:2AlvjvjZ
/** Qsr+f~"W
* @param userDAO The userDAO to set. (bGk=q=M
*/ #c`/ f6z
publicvoid setUserDAO(UserDAO userDAO){ L?b;TjLe
this.userDAO = userDAO; .N Z
} GBGna3
r5PZ=+F
/* (non-Javadoc) x{$/|_
* @see com.adt.service.UserManager#listUser ffem7eQ
[g$IN/o%
(org.flyware.util.page.Page) BYb"[qPV
*/ J''lOj(@
public Result listUser(Page page)throws \NQ[w7
7$Pf
HibernateException, ObjectNotFoundException { -n6e;p]
int totalRecords = userDAO.getUserCount(); DWk2=cO
if(totalRecords == 0) <ua! ]~
throw new ObjectNotFoundException (T =u_oe
MQlGEJ
("userNotExist"); >xIb|Yp)&
page = PageUtil.createPage(page, totalRecords); *:Y9&s^6j
List users = userDAO.getUserByPage(page); c) _u^Dh
returnnew Result(page, users); 8l>YpS*S^
} /O[Z
eY3<LVAX
} u Uh6/=y
MUMB\K*$
F2dwT
Ej$oRo{IG
Nq[-.}Z6
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @{@)gE
cs)R8vuB)z
询,接下来编写UserDAO的代码: qDjH^f
3. UserDAO 和 UserDAOImpl: 6Q}>=R^h
java代码: ;rt\
Y|-:z@n6C
`6pz9j]
/*Created on 2005-7-15*/ K,H xe;-
package com.adt.dao; ,gIeQ!+vy
lYy:A%yDT
import java.util.List; @ [j%V ynf
C0H@
import org.flyware.util.page.Page; -;GB Xq
)T'~F
import net.sf.hibernate.HibernateException; mJME1#j$/|
=Kt!+^\")
/** ;tfGhHpQn
* @author Joa ^'4I%L"
*/ d@{#F"o
publicinterface UserDAO extends BaseDAO { ]NY^0SqM
N`7+]T
publicList getUserByName(String name)throws /n3S E0Y
P7;q^jlB
HibernateException; "QM2YJ55m`
)H%RwV#
publicint getUserCount()throws HibernateException; 9&1$\ZH
f!JSb?#3
publicList getUserByPage(Page page)throws bJFqyK:6
[q(}~0{"-
HibernateException; kDc/]Zb%
VoNk.h"T
} K9S(Xip
XknbcA|
NP$ D9#
1N +ju"2R
fP{IW`t}]
java代码: bl4I4RB
$A>]lLo0
g7Z3GUCGL
/*Created on 2005-7-15*/ Hx ojxZwm
package com.adt.dao.impl; @EUvx
j +Ro?
import java.util.List; /@6T~XY M
h{CyYsQ
import org.flyware.util.page.Page; CA,2&v"
p}q]GJ
import net.sf.hibernate.HibernateException; vJ uL+'[i
import net.sf.hibernate.Query; T_<:
%wIb@km
import com.adt.dao.UserDAO; s h}eKwh
C40W@*6S2
/** T,v5cc:nO
* @author Joa G[Jz(/yNH
*/ TGI`}#
public class UserDAOImpl extends BaseDAOHibernateImpl q(}#{OO
M[^EHa<i
implements UserDAO { ? 1Uq ud
;i&t|5y~
/* (non-Javadoc) r\m2Oo)]
* @see com.adt.dao.UserDAO#getUserByName l!%V&HJV
Ol*|J
(java.lang.String) =${ImMwj
*/ #
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publicList getUserByName(String name)throws 6R!AIOD>
'PdUSv|lH
HibernateException { .a}!!\@
String querySentence = "FROM user in class ^fvx2<
qino:_g
com.adt.po.User WHERE user.name=:name"; i^V3u
Query query = getSession().createQuery fs*OR2YG7
+}NQ|y V
(querySentence); zO3}c3D~q
query.setParameter("name", name); "Fqrk>Q~
return query.list(); G_6!w//
} 42wZy|oqp
H2E'i\
/* (non-Javadoc) -<^3!C >
* @see com.adt.dao.UserDAO#getUserCount() kl#)0yqN0
*/ oNRp
publicint getUserCount()throws HibernateException { &p.7SPQ8/
int count = 0; )Z63 cr/
String querySentence = "SELECT count(*) FROM T0K*!j}O
p.!p6ve){
user in class com.adt.po.User"; ivPX_#QI
Query query = getSession().createQuery _6C,w`[[6
T_~xDQ` v
(querySentence); CMHg]la
count = ((Integer)query.iterate().next =v~$&@
@<44wMp
()).intValue(); Z^GXKOeq
return count; h($Jo
} {D4N=#tl
tDNo; f
/* (non-Javadoc) (0zYS_mA
* @see com.adt.dao.UserDAO#getUserByPage l# |M.V6G
&F|Wk,y
(org.flyware.util.page.Page) S?#'Y*h
*/ tMr$N[@r
publicList getUserByPage(Page page)throws 2G}@s.iE
?,FL"ye
HibernateException { pNc4o@-
String querySentence = "FROM user in class LgA>,.
AI3\eH+
com.adt.po.User"; nLBi}T
Query query = getSession().createQuery !9EbG
QykHB
k
(querySentence); pcPRkYT[M
query.setFirstResult(page.getBeginIndex()) Is}?:ET
.setMaxResults(page.getEveryPage()); RH&}'4JE:
return query.list(); QHe:
} Y,d|b V*FH
CpC6vA.R
} I9kBe}g3
a>Xq
KZwzQ" Hl
yb'v*B]
RBOhV/f
至此,一个完整的分页程序完成。前台的只需要调用 kk+:y{0V
[I%'\CI;
userManager.listUser(page)即可得到一个Page对象和结果集对象 HG[gJ7
txy'7t
的综合体,而传入的参数page对象则可以由前台传入,如果用 _OR[RGy
#L xfE<^
webwork,甚至可以直接在配置文件中指定。 $
Bdxu
a`S3v
下面给出一个webwork调用示例: _Uup*#m
java代码: wI2fCq(a0
2Q[q)u
`}*jjnr"
/*Created on 2005-6-17*/ vjYG>YhV
package com.adt.action.user; T%1Kh'92
H^8t/h
import java.util.List; |p":s3K"Hy
]d,#PF
import org.apache.commons.logging.Log; ( ALsc@K
import org.apache.commons.logging.LogFactory; d$v{oC}
import org.flyware.util.page.Page; 8:}$L)[V
3vF-SgCV
import com.adt.bo.Result; N"/be
import com.adt.service.UserService; =N{-lyr)
import com.opensymphony.xwork.Action; f9J]-#I if
l[{Ci|4
/** o)Nm5g
* @author Joa 5C"A*Fg?;
*/ ~Ec@hz]js
publicclass ListUser implementsAction{ tq5o
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privatestaticfinal Log logger = LogFactory.getLog xwu,<M
v`
UJGmaE
(ListUser.class); a8r+G]Z
nF{>RD
private UserService userService; p0j-$*F
3G-f+HN^E
private Page page; }t5pz[zl
}#9 |au`
privateList users; `pYL/[5
3Tr}t.mt
/* ,:"c"
* (non-Javadoc) KPs
@v@5M
* M@O<b-
* @see com.opensymphony.xwork.Action#execute() T
eBJ
*/ S3_QOL
publicString execute()throwsException{ u^&,~n@n7
Result result = userService.listUser(page); 5b%zpx0Y
page = result.getPage(); 0+"P1/
users = result.getContent(); 9NcC.}#-5
return SUCCESS; Lcy>!3q3~
} `jH 0FJQ
wfc+E9E
/** ru1FJ{n
* @return Returns the page. RaY=~g
*/ s h^&3}
public Page getPage(){ 5 }F6s
return page; kNTxYJ
} R3} Z"
aW#_"Y}v'
/** %TRH,-@3h
* @return Returns the users. "Kt[jV;6
*/ Xu&4|$wB+
publicList getUsers(){ MA5BTq<&
return users; ?3Dsz
} }-ysP$
zj9aaZ}
/** >l|dLyiae
* @param page YfOO]{x,X
* The page to set. O{`r.H1',
*/ CF+:9PG
publicvoid setPage(Page page){ .=-K7.X.)
this.page = page; @X*r5hjc
} F6\r"63
'aW<C>
/** E>6:59+
* @param users e8<[2J)P&
* The users to set. z hFk84
*/ BFyVq
publicvoid setUsers(List users){ `jB2'
this.users = users; ;yK:.Vg
} Z]Iyj
97
OM
5h>\9
/** haMt2S2_B:
* @param userService B#;yko
* The userService to set. _fQBXG2
*/ eA(c{
publicvoid setUserService(UserService userService){ J#'+&DH
this.userService = userService; b?FTwjV+#
} &-1;3+#w
} y1:#0
<sq@[\l}a
7lz"^
jNA^
(|:
A1,- qv1s
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, #.n%$r
<xeo9'k6&
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 y*5bF0
B?tO&$s
么只需要: Z*(lg$A9M
java代码: tkGJ!aUt
>O&:[CgEF
]1<O [d
<?xml version="1.0"?> >HXmpu.O
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork +k4SN
h&6v&%S/L
1.0//EN" "http://www.opensymphony.com/xwork/xwork- *m[ow s
R83Me#&
1.0.dtd"> p4OiCAW;
pZ4]oK\*
<xwork> P$= Y 5
U3yIONlt
<package name="user" extends="webwork- /n SmGAO
8?rRLM4
interceptors"> *0`oFTJ
r%/*,lLO
<!-- The default interceptor stack name H]7;OM/g
3yfq*\_uXw
--> )} H46
<default-interceptor-ref p}'uCT
ga
Fhn=}7|4q
name="myDefaultWebStack"/> v*7lJNN.
H `V3oS~}
<action name="listUser" ?][2J
@*gm\sU4
class="com.adt.action.user.ListUser">
TVP.)%
<param i>C:C>~
# N.(ZP
name="page.everyPage">10</param> ![BQ;X
<result .hxcx>%
|E)Es!dr
name="success">/user/user_list.jsp</result> 'MHbXFM
</action> ''f07R
dik+BBu5z
</package> N@>,gm@UU
+)Pv6Zog[
</xwork> }'KVi=qnHb
VBIY[2zf
x^|J-
e:Zc-
0pS|t/h0
]r{-K63P{!
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 <z*SO
a
w$cic
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 oO4
Wwi
l*|^mx^Q
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Gw$sL&1m\
2>3gC_^go
e%'$Vx0kA
:H$D-pbJ4
[9WtoA,kx
我写的一个用于分页的类,用了泛型了,hoho _|S>,D'
_G!lQ)1
java代码: [y73
xF
.oq!Ys4KA
bqXCe\#
package com.intokr.util; AFWcTz6 #d
lGI5
import java.util.List; 6s833Tmb&r
e'oM%G[
/** :4"SJ
* 用于分页的类<br> +b.qzgH>r
* 可以用于传递查询的结果也可以用于传送查询的参数<br> _$me.
* }*~EA=YN;
* @version 0.01 7 N?x29
* @author cheng `MgR/@%hr
*/ 4-4lh
TE(
public class Paginator<E> { C^S?W=1=w
privateint count = 0; // 总记录数 )*I=>v.Jq
privateint p = 1; // 页编号 dF{3~0+,
privateint num = 20; // 每页的记录数 j[XA"DZR<
privateList<E> results = null; // 结果 8z^?PZ/
K2TO,J3 E
/** |i"A!rW
* 结果总数 sD$
\!7:b
*/ )""i"/Mn
publicint getCount(){ OYJy;u3"
return count; {_1^ GIIS
} ,P ?TYk
-L4AM%(9
publicvoid setCount(int count){ N7%+n*Z
this.count = count; 5r<%xanXW/
} PXcpROg56
oW-Tw@D
/** N5rY*S
* 本结果所在的页码,从1开始 cWl)ZE<hM
* (XJehdB0
* @return Returns the pageNo. I?v)>||Q
*/ XnQd(B`M
publicint getP(){ Bo?uwi
return p; CJ_X:Frj)
} GV1\8OG7
Y;je ::"
/** i+yqsYKO
* if(p<=0) p=1 a}a_&rf~Z
* *$x/(!UE
* @param p >\K<q>*
*/ /d5_-AB(v
publicvoid setP(int p){ a\\B88iRRZ
if(p <= 0) 4@|K^nT`
p = 1; -vI?b#
this.p = p; .b]g#Du=
} Z9ciS";L
v@;:aN
/** j-ugsV`2=*
* 每页记录数量 C8cB Lsa[J
*/ 7Nc@7_=
publicint getNum(){ x{u_kepv[k
return num; ?L#C'Lz2+
} cD8.rRyD
?6B)Ek,'X?
/** %}P^B^O
* if(num<1) num=1 MQ2gzKw>
*/ ={b/s31H:
publicvoid setNum(int num){ y-}lz#N
if(num < 1) 2GcQh]ohc
num = 1; ]Ole#Lz}Q
this.num = num; it\{#rb=4
} a=k+:=%y
XZuJ<]}X,
/** a=gTGG"9
* 获得总页数 &Z5$
5,[
*/ 0G9@A8LU
publicint getPageNum(){ B4R!V!Z*
return(count - 1) / num + 1; 'g#Ml`cm
} fyx-VXu
TQ" [2cY
/** AynWs5|z=
* 获得本页的开始编号,为 (p-1)*num+1 Eszwg
*/ 8[,,Kr)-
publicint getStart(){ A$A7F=x
return(p - 1) * num + 1; 2Ua_7
} \P!v9LX(
LLg ']9
/** TclZdk]%T
* @return Returns the results. g8mVjM\B;
*/ [+gX6
publicList<E> getResults(){ P$2J`b[H$
return results; 7'j?GzaQ+
} 8 +xLi4Pw
WE4:Jy
public void setResults(List<E> results){ {O#=%o[
this.results = results; K8{j oh
} OCo=h|qBp
b=-<4Vu*\
public String toString(){ b^ly
StringBuilder buff = new StringBuilder J @"wJEF
R+gh 2
6e
(); zUXqTcj
buff.append("{"); P$.Azrl
buff.append("count:").append(count); $2Ox;+
buff.append(",p:").append(p); )qD%5} t
buff.append(",nump:").append(num); 5bv(J
T
buff.append(",results:").append XYWGX;.=
jN 5Hku[?
(results); tHXt*tzq
buff.append("}"); dI-=0v-|
return buff.toString(); w48T?
}
q>r9ooN
y .S0^
} A2uSH@4
XV)ej>A-V
t3 *2Z u