Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 )9'Zb`n
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 %"g; K
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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 <`WtP+`
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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 WpPI6bd
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分页支持类: g&`[r6B
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java代码: 2"C,u V@F!
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package com.javaeye.common.util; p4M7BK:nf
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import java.util.List; L qdzqq
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publicclass PaginationSupport { sad[(|
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publicfinalstaticint PAGESIZE = 30; )3A%Un#B
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privateint pageSize = PAGESIZE; VH2/
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privateList items; L$4nbOu\~
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privateint totalCount; }Asp=<kCc
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privateint[] indexes = newint[0]; Ye"#tCOEG
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privateint startIndex = 0; Aa`'g0wmc
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public PaginationSupport(List items, int Dh~Z8!*
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totalCount){ ' &j]~m
setPageSize(PAGESIZE); >S=,ype~G
setTotalCount(totalCount); 9d1 Gu"
setItems(items); 7UA|G2Zr
setStartIndex(0); j3yz"-53e
} ZK8I f?SD
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public PaginationSupport(List items, int ga+Z6|t
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totalCount, int startIndex){ qk=0ovUzg
setPageSize(PAGESIZE); h(H b+7g
setTotalCount(totalCount); +KKx\m*
setItems(items); K}1eQS&$a
setStartIndex(startIndex); Sw^-@w=!U5
} ]`GDZw`
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public PaginationSupport(List items, int **L3T3$)
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totalCount, int pageSize, int startIndex){ >W7IWhm3
setPageSize(pageSize); DA-W =Cc
setTotalCount(totalCount); O| zLD
setItems(items); xzjG|"a[GB
setStartIndex(startIndex); 5'hQ6i8
} wc7F45l4
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publicList getItems(){ <=7N2t)s4
return items; 08JVX'X-mr
} @!zT+W&
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publicvoid setItems(List items){ >(:b\*C
this.items = items; S+Vsy(
} Yiy|^j
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publicint getPageSize(){ LJII7<k
return pageSize; |`i.8
} :U$U:e
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publicvoid setPageSize(int pageSize){ 9}DF*np`G
this.pageSize = pageSize; LwL\CE_6+
} 0nOp'Ky\k
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publicint getTotalCount(){ [J6b5
return totalCount; 6ISDY>p
} L.M|o
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publicvoid setTotalCount(int totalCount){ ZRr S""V
if(totalCount > 0){ ?=X_a{}/
this.totalCount = totalCount; maopr$r
int count = totalCount / &$
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pageSize; 1=X"|`<!
if(totalCount % pageSize > 0) B{+ Ra
count++; zu-1|XX
indexes = newint[count]; WJN}d-S=^
for(int i = 0; i < count; i++){ h]z>H~.<*
indexes = pageSize * Jxy94y*
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i; l-mf~{
} !j|93*
}else{ HD95>%
this.totalCount = 0; _2C[F~ +l
} 2AZ)|dM'`
} G,J~Ed
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publicint[] getIndexes(){ |vY0[#E8&
return indexes; d|8iD`sZz
} %Kq`8
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publicvoid setIndexes(int[] indexes){ cjel6 nj
this.indexes = indexes; / NlT[@T
} aj:B+}1
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publicint getStartIndex(){ c#6g[TE@
return startIndex; *1[v08?!
} `/z6Q"
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publicvoid setStartIndex(int startIndex){ l[EjtN
if(totalCount <= 0) MXj7Z3
this.startIndex = 0; rHWlv\+Nn
elseif(startIndex >= totalCount) pwvcH3l/r
this.startIndex = indexes '~ {x n
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[indexes.length - 1]; lV0\UySH
elseif(startIndex < 0) NHCdf*
this.startIndex = 0; -OS&(7
else{ u0(PWCi2
this.startIndex = indexes d* 6 lJT
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[startIndex / pageSize]; oe:@7stG
} @!:~gQ
} l`vb
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publicint getNextIndex(){ ?(^HjRUY
int nextIndex = getStartIndex() + j5EZJ`
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pageSize; hF!t{ Lf3
if(nextIndex >= totalCount) !P &F6ViO=
return getStartIndex(); U Ux]
else c_fx,;
;
return nextIndex; rK%A=Q
} 0DBA 'Cv
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publicint getPreviousIndex(){ Y70[Nz
int previousIndex = getStartIndex() - bJo)rM:m
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pageSize; V2I"m
if(previousIndex < 0) 4Em mh=A
return0; X&[S.$_U
else $`Z-,AJc
return previousIndex; hwaU;> F
} $EB&]t+
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} !c+Nf2I7S
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}jQxwi)
抽象业务类 "i\rhX
java代码: 93-UA.+g
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/** S`Jo^!VJ4
* Created on 2005-7-12 :)UF#
*/ TU-4+o%;
package com.javaeye.common.business; S0\;FmLIc
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import java.io.Serializable; QQso<.d&
import java.util.List; v>FsP$p4yE
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import org.hibernate.Criteria; :@:i*2=
import org.hibernate.HibernateException; brA\Fp^
import org.hibernate.Session; 3iHUG^sLW
import org.hibernate.criterion.DetachedCriteria; hlpi-oW`
import org.hibernate.criterion.Projections; iyF~:[8
import mTcop yp
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org.springframework.orm.hibernate3.HibernateCallback; i+$G=Z#3E
import BitP?6KX
B&~#.<23:
org.springframework.orm.hibernate3.support.HibernateDaoS R\%&Q|
2nW:|*:/p6
upport; 3[g%T2&[
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import com.javaeye.common.util.PaginationSupport;
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public abstract class AbstractManager extends d%:B,bck
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HibernateDaoSupport { M^c`j#NQ
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privateboolean cacheQueries = false; g]IRv(gDh
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privateString queryCacheRegion; }Fd4;
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publicvoid setCacheQueries(boolean ^t&S?_DSZ
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cacheQueries){ }pJ6CW
this.cacheQueries = cacheQueries; 3BuG_ild
} _d#1muZ?p|
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publicvoid setQueryCacheRegion(String '?Mt*%J@=$
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queryCacheRegion){ zW^_w&fd^j
this.queryCacheRegion = ^gb3DNV~y
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queryCacheRegion; 'c[[H3s!;
} <l/QS3M
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publicvoid save(finalObject entity){ p^|IN'lx,
getHibernateTemplate().save(entity); ]Ek6EuaK
} <j}n/G]
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publicvoid persist(finalObject entity){ g.wp
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getHibernateTemplate().save(entity); |JZ3aS
} v~f_~v5J!
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publicvoid update(finalObject entity){ &cDLSnR
getHibernateTemplate().update(entity); Hc`)Q vFRW
} EwvW: t1
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publicvoid delete(finalObject entity){ WmO.&zp
getHibernateTemplate().delete(entity); )-D{]>8
} C`s
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publicObject load(finalClass entity, ldd|"[Ds
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finalSerializable id){ v6Vie o=
return getHibernateTemplate().load J!O{.v
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(entity, id); dNH6%1(s]0
} VRuY8<E
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publicObject get(finalClass entity, b-Q*!Ut
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finalSerializable id){ xLxXc!{J5
return getHibernateTemplate().get =L,s6J8_'
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(entity, id); %gK@R3p
} 4R 9lA
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publicList findAll(finalClass entity){ =<,>dBs}\
return getHibernateTemplate().find("from yQAW\0`
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" + entity.getName()); :c4iXK0_^?
} DhN{Y8'~
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publicList findByNamedQuery(finalString xF:}a:c@H
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namedQuery){ G~z=,72
return getHibernateTemplate K90wX1&
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().findByNamedQuery(namedQuery); e"^ /xF
} xEW>7}+\
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publicList findByNamedQuery(finalString query, 1~J:hjKQ
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finalObject parameter){ YkOl@l$D
return getHibernateTemplate ]H ze
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().findByNamedQuery(query, parameter); S&yKi
} .b.pyVk
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publicList findByNamedQuery(finalString query, r#8t@W
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finalObject[] parameters){ GSHJ?}U,
return getHibernateTemplate %pikt7,Z~
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().findByNamedQuery(query, parameters); $w,O[PIi
} '?j[hhfB-
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publicList find(finalString query){ f*Z8C9)
return getHibernateTemplate().find WruSL|4iH
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(query); 8C,}nh
} y7f,]<%e_
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publicList find(finalString query, finalObject E#?Bn5-uBs
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parameter){ }PC_qQF
return getHibernateTemplate().find ID{62>R
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(query, parameter); V-1H(wRu
} 5|nT5oS
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public PaginationSupport findPageByCriteria %-lilo
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(final DetachedCriteria detachedCriteria){ %S`ygc}|
return findPageByCriteria hg2a,EU\Z
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); sJI"
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} aXv[~
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public PaginationSupport findPageByCriteria M0jC:*D`"
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(final DetachedCriteria detachedCriteria, finalint )9pRT
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startIndex){ G+_Q7-o&d6
return findPageByCriteria pB;U*lt
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(detachedCriteria, PaginationSupport.PAGESIZE, [Re.sX}$Y
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startIndex); [Sj _=
} =c-Y >
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public PaginationSupport findPageByCriteria 0uZL*4A+C
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(final DetachedCriteria detachedCriteria, finalint ??]b,f4CNa
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pageSize, !#NGGIp;
finalint startIndex){ MD4RSl<F
return(PaginationSupport) ' ?4\
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getHibernateTemplate().execute(new HibernateCallback(){ w\K(kNd(
publicObject doInHibernate Wr j<}L|
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(Session session)throws HibernateException { Zra P\ ?
Criteria criteria = pu"m(9
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detachedCriteria.getExecutableCriteria(session); G?,b51"
int totalCount = <MQTOz
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((Integer) criteria.setProjection(Projections.rowCount Il4R R
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()).uniqueResult()).intValue(); %2I >0
criteria.setProjection v1R t$[
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(null);
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List items = m=4hi(g
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criteria.setFirstResult(startIndex).setMaxResults ^~7/hm:
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(pageSize).list(); r%uka5@
PaginationSupport ps = #5%\~f
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new PaginationSupport(items, totalCount, pageSize, G m~2s;/
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startIndex); } %bP9
return ps; _SQQS67fu"
} g7l?/p[n
}, true); 6k=*O|r
} "9v4'"
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public List findAllByCriteria(final z+5%.^Re
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DetachedCriteria detachedCriteria){ PAy/"R9DT-
return(List) getHibernateTemplate Dk^T_7{
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().execute(new HibernateCallback(){ Z.%0yS_T
publicObject doInHibernate P+Q}bTb8
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(Session session)throws HibernateException { lJJ`aYDp
Criteria criteria = !+)5?o
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detachedCriteria.getExecutableCriteria(session); -)%gMD~z1
return criteria.list(); \c\z 6;j
} TN=!;SvQU
}, true); 2[X\*"MQ2
} DedY(JOvB
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public int getCountByCriteria(final 3%(BZ23
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DetachedCriteria detachedCriteria){ 4XNdsb
Integer count = (Integer) CQns:.`$`
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getHibernateTemplate().execute(new HibernateCallback(){ ..fbRt
publicObject doInHibernate `L
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(Session session)throws HibernateException { i`7(5L~`
Criteria criteria = ?m\?
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detachedCriteria.getExecutableCriteria(session); VUUE2k;^
return o^3X5})sv
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criteria.setProjection(Projections.rowCount iOdk)
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()).uniqueResult(); O"ebrv
} >|rU*+I`
}, true); V'8Rz#Gc5
return count.intValue(); }G ^nK m
} *cy!PF&
} 1a
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用户在web层构造查询条件detachedCriteria,和可选的 XR+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 l&_PsnU
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PaginationSupport的实例ps。 l\_81oZ
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ps.getItems()得到已分页好的结果集 Ya29t98Pk
ps.getIndexes()得到分页索引的数组 Jy
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ps.getTotalCount()得到总结果数 >c=-uI
ps.getStartIndex()当前分页索引 D zdKBJT +
ps.getNextIndex()下一页索引 K)#6&\0tT
ps.getPreviousIndex()上一页索引 71c(Nw~iQ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 XaH;
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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 oIGF=x,e8
5 89P$2e1X
一下代码重构了。 W.^R/s8O%5
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我把原本我的做法也提供出来供大家讨论吧: ^[.Z~>3!\q
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首先,为了实现分页查询,我封装了一个Page类: ]VoJ7LoCZ'
java代码: "J{A}g[
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/*Created on 2005-4-14*/ Y'Yu1mH)
package org.flyware.util.page; 5Bp>*MR/".
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/** 3|(3jIa
* @author Joa 'iX y?l
* d0 mfqP=
*/ IweNe`Z
publicclass Page { vu~7Z;y(<j
ot,=.%O
/** imply if the page has previous page */ nq:'jdY5|
privateboolean hasPrePage; KT0Pmpp5
l{Xy %8
/** imply if the page has next page */ g(l:>=g]?
privateboolean hasNextPage; T U^s!Tj
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/** the number of every page */ 5s:g(gy3BR
privateint everyPage; -Yg?@yt
=kb/4eRg
/** the total page number */ ]<k+a-Tt
privateint totalPage; "4L_BJZ
y3ST0=>j}
/** the number of current page */ {'6-;2&f
privateint currentPage; %']`t-N8
.>NPgdI
/** the begin index of the records by the current `8kL=%(h
W?gelu]
query */ lz4M)pL^
privateint beginIndex; 3Qd%`k
1"No~/_
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/** The default constructor */ fv:&?gc
public Page(){ h]WW?.
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} I^m9(L4%
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/** construct the page by everyPage p/gf
* @param everyPage &R3#? 1,
* */ IZ@M
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public Page(int everyPage){ sOm&7A?
this.everyPage = everyPage; {j%7/T{
} G|j8iV O
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/** The whole constructor */ 8u"HW~~=
public Page(boolean hasPrePage, boolean hasNextPage, OBf$0
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int everyPage, int totalPage, UB]]oC<
int currentPage, int beginIndex){ Wql,*|
this.hasPrePage = hasPrePage; IJBIO>Z/
this.hasNextPage = hasNextPage; kyL]4:@W`
this.everyPage = everyPage; O+=C8
this.totalPage = totalPage; 8@]vvZ2/gj
this.currentPage = currentPage; XhmUtbs
this.beginIndex = beginIndex; vP^V3
} R(IYb%L
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/** V1\Rj0#G
* @return s'$3bLcb
* Returns the beginIndex. k<
*/ '
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publicint getBeginIndex(){ Tua#~.3}J
return beginIndex; }Io5&ww:U
} eV\VR
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/** Q1P=A:*]9
* @param beginIndex l8+;)2p!
* The beginIndex to set. HxNoV.q
*/ !Aw.)<teW
publicvoid setBeginIndex(int beginIndex){ R T/)<RT9
this.beginIndex = beginIndex; ]%+T+zg(Y
} 3ZhuC".c
I~ e,']
/** B>%;"OMp
* @return sfs2ki H
* Returns the currentPage. ^=y%s
*/ Y``]66\Fp
publicint getCurrentPage(){ T]2=
return currentPage; '6GW.;
} c:2LG_mQ
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/** "ed
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* @param currentPage '1b4nj|<m
* The currentPage to set. @cn8 m
*/ kNoS% ?1,
publicvoid setCurrentPage(int currentPage){ )pG*_q
this.currentPage = currentPage; 98lz2d/Fcq
} "f>`ZFp^
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/** !mK}Rim~
* @return y0,>_MS
* Returns the everyPage. jAfqC@e
*/ 0HDL;XY6
publicint getEveryPage(){ B:(a?X-7
return everyPage; z,(.` %h
} n"f:6|<
f}7/UGd
/** nc;iJ/\4
* @param everyPage T}K@ykT
* The everyPage to set. WntolYd
*/ gq050Bl)
publicvoid setEveryPage(int everyPage){ "8/BVW^bv
this.everyPage = everyPage; F-GH?sfvi
} [m(n-MuF
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/** w9C?wT
* @return "/d
* Returns the hasNextPage. f'OcW*t
*/ \12y,fOJ
publicboolean getHasNextPage(){ UHX,s
return hasNextPage; a$$aM2.2
} Dmr3r[
'?d5L+9
/** 5QZ}KNJ|t~
* @param hasNextPage x2tcr+o
* The hasNextPage to set. :\~YbA
*/ 8BX9JoDi
publicvoid setHasNextPage(boolean hasNextPage){ 2j=HxE
this.hasNextPage = hasNextPage; K,dEa<p
} G x{G}9
zh9B8r)C
/**
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* @return 9EWw
* Returns the hasPrePage. .-GC,&RO
*/ S>y}|MG
publicboolean getHasPrePage(){ iO 7s zi
return hasPrePage; CRu {Ie5B
} (= Wu5H
vPD%5AJN
/** `+@r0:G&v
* @param hasPrePage
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* The hasPrePage to set. CQH^VTQ
*/ 0Z
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publicvoid setHasPrePage(boolean hasPrePage){ H6<3'P
this.hasPrePage = hasPrePage; VMw[M^
} JdX!#\O
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/** {~ 1
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* @return Returns the totalPage. 9(hI%idq
* 7E;`1lh7
*/ |l:,EA_v|
publicint getTotalPage(){ $'COsiK7
return totalPage; (Ji=fh+
} !&pk^VFl+
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/** ]~4*ak=)5\
* @param totalPage Gk!CU"`sP
* The totalPage to set. VN]j*$5
*/ duoM>B>8]
publicvoid setTotalPage(int totalPage){ ftP]WGSS>
this.totalPage = totalPage; -gpHg
} BQ(sjJ$v6F
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} j<}y( ~
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yDAvl+
C@ "l"
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 2tZ\/6G<
=Q4Wr0y><]
个PageUtil,负责对Page对象进行构造: fnK H<
java代码: L6J.^tpO
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/*Created on 2005-4-14*/ !jRs5{n^Ol
package org.flyware.util.page; 51`*VR]`K
GP_%.fO\M
import org.apache.commons.logging.Log; L<p.2[3
import org.apache.commons.logging.LogFactory;
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\{ff7_mLo
/** Qk].^'\
* @author Joa 7mnZ,gpb
* Q'0:k{G
*/ *yN#q>1
publicclass PageUtil { 3<}r+, j
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privatestaticfinal Log logger = LogFactory.getLog K'b #}N\
Z%QU5.
(PageUtil.class); Z=^~]Mfa
7$"n.cr
:
/** wa$Q8/
* Use the origin page to create a new page 3($tD*!o
* @param page !XT2'6nu
* @param totalRecords B4w/cIj_
* @return 2]+f<Z[/
*/ `ex>q
publicstatic Page createPage(Page page, int W&e}*
"(vm0@8><
totalRecords){ Wn5xX5H C
return createPage(page.getEveryPage(), JF(&+\i<p
}nMp.7b
page.getCurrentPage(), totalRecords); -x+K#T0Z
} "T~A*a^
f#
sDG
/** =[YjIWr#o
* the basic page utils not including exception 5KL??ao-
J@o$V- KK
handler $q0i=l&$&
* @param everyPage >44,Dp]
* @param currentPage kw5`KfG9
* @param totalRecords R&MetQ~-{
* @return page !z"nJC
*/ Kk 6i
publicstatic Page createPage(int everyPage, int {3K`yDF
T49^
currentPage, int totalRecords){ rl:D>t(:.
everyPage = getEveryPage(everyPage); o=Ia{@
currentPage = getCurrentPage(currentPage); z;PF%F
int beginIndex = getBeginIndex(everyPage, 6yedl0@wa!
nOq`Cwh9
currentPage); U_@Dn[/:
int totalPage = getTotalPage(everyPage, 1_5]3+r_U-
d5qGTT ~a
totalRecords); ;I]$N]8YI
boolean hasNextPage = hasNextPage(currentPage, -H"^;37T"
_PGS"O?j
totalPage); j&Y{
CFuZ
boolean hasPrePage = hasPrePage(currentPage); @hOT<
Uo
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returnnew Page(hasPrePage, hasNextPage, }/M`G]wT#
everyPage, totalPage, 5 8gkE94
currentPage, gi<%: [jT
S=g E'"LT
beginIndex); mEq>{l:
}
u'qc=5
jDCf]NvOPM
privatestaticint getEveryPage(int everyPage){ x1`zD*{
return everyPage == 0 ? 10 : everyPage; ]DLs'W;)
} {{ +8oRzY
:;N2hnHoG
privatestaticint getCurrentPage(int currentPage){ TS@U0Ror
return currentPage == 0 ? 1 : currentPage; ->5[C0: ]
} PQ(/1v
-5<G^AS
privatestaticint getBeginIndex(int everyPage, int ~otV'= /my
8W}rSv+
currentPage){ o~ReeZ7)Zg
return(currentPage - 1) * everyPage; K<?[^\
} ?HP{>l0r
QUz_2rN^
privatestaticint getTotalPage(int everyPage, int gv/yfiA?
dW#?{n-H<
totalRecords){ R/kfbV-b
int totalPage = 0; `{'h+v`
*2r(!fJP=^
if(totalRecords % everyPage == 0) tS6r4d%~=
totalPage = totalRecords / everyPage; aIklAj)=
else JwcC9
O
totalPage = totalRecords / everyPage + 1 ; RgLk AHA
JeU1r-i
return totalPage; b%|6y
} P B"nf|pm
_QiGrC
privatestaticboolean hasPrePage(int currentPage){ XA-,
return currentPage == 1 ? false : true; "In$|A\?E
} <gx"p#JbZ
g/`z.?
privatestaticboolean hasNextPage(int currentPage, -59;Zn/
; 8u5
int totalPage){ uAv'%/
return currentPage == totalPage || totalPage == <M M(Z
fx= %e
0 ? false : true; `;z;=A*
} {z7kW@c
a'B 5m]%
./Wi(p{F
} <*5` TE0J
yI8
/m|
tnFhL&
^1`T_+#[s
jn#Ok@tZ
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。 n/Dk~Q)
`g:bvIV5x>
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 8|-064i>
95oh}c
做法如下: <(B: "wI
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 f%c-
"Sd2VSLg
的信息,和一个结果集List: 4Q^i"jT
java代码: <77v8=as5
:1e'22[=.
6Y/TqI[
/*Created on 2005-6-13*/ |n\(I$
package com.adt.bo; psB9~EU&Q
=pn(56
import java.util.List; G?v]|wdI
q{RT~,%
import org.flyware.util.page.Page; * ;<>@*
T``~YoIdz
/** yNN_}9
* @author Joa ~:):.5o
*/ &-4SA j
publicclass Result { =\)qUs\z
#(d/A<
private Page page; o]m56
BV6
U -
private List content; LKI2R_|n
M;1B}x@
/** Ub<^;Du5
* The default constructor <!I^ xo[
*/ 6%2\bI.#
public Result(){ )}5f'TK
super(); O
-N>
X
} =-8y=
y2NVx!?n
/** 7g&<ZZo
* The constructor using fields 0}
Lx}2
* >d#Ks0\&
* @param page S}XVr?l2O
* @param content _-bEnF+/0
*/ jGKas I`
public Result(Page page, List content){ $Y_v X
2
this.page = page; ulxy 4] h
this.content = content; 0vi\o`**Mj
} _33YgO
_chX
{_Hu-
/** i`HXBq!|w
* @return Returns the content. .GNl31f0
*/ _U/C G<n
publicList getContent(){ 7="I;
return content; !nyUAZ9 :
} iXFN|ml
p/.[cH
/** AcxC$uh
* @return Returns the page. ro*$OLc/
*/ O7GJg;>?
public Page getPage(){ Hp?uYih0
return page; 8i'EO6
} DJ<F8-sb2r
7T-}oNaJA\
/** Wf!<Qot|R#
* @param content d@,3P)?
* The content to set. LwS>jNJx
*/ M>"J5yqR
public void setContent(List content){ 8n Oent0a
this.content = content; {\zB'SNq
} ?^W`7H F%0
0w<qj T^U
/** xlU:&=|
* @param page =}Xw}X+[WY
* The page to set. xyc`p[n&
*/ %)@3V8 OI
publicvoid setPage(Page page){ ^=gzms
this.page = page; Zi~-m]9U
} o" ./
} /6a617?9J
SYmiDR
k>dzeH
)A H)*Mg
r2; )VS
2. 编写业务逻辑接口,并实现它(UserManager, MuCnBx
9q|36CAO_
UserManagerImpl) @E@5/N6M
java代码: j,i>
1|J
{]=oOy1
#{oGmzG!
/*Created on 2005-7-15*/ p:9^46N@
package com.adt.service; dqo&3^px
A%dI8Z,
import net.sf.hibernate.HibernateException; Th[Gu8b3
;H:+w\?8f$
import org.flyware.util.page.Page; >Lrud{
Y<oDv`aZ0
import com.adt.bo.Result; T~(AXwaJ
S6pvbaMZ
/** ^RO_B}n3
* @author Joa %V3xO%
*/ *{e?%!Q
publicinterface UserManager { Zo(p6rku
G0VbW-`O
public Result listUser(Page page)throws i!9|R)c
It8m]FN
HibernateException; Af%#&r7W
4x%R4tk
} |37y ="
bTN0 n
?3)
IzzO
MY `V0
D%NVqk|
java代码: BavGirCp
{s/u[T_D2
Gv uX"J
/*Created on 2005-7-15*/ w~I;4p~(N
package com.adt.service.impl; dN)!B!*aI
&!pG1Fp9
import java.util.List; ^~:&/ 0
Y;[#~3CA
import net.sf.hibernate.HibernateException; Udbz;^(
+rA:/!b)Y
import org.flyware.util.page.Page; ;^`WX}]C(
import org.flyware.util.page.PageUtil; ?}g#Mc
)]~;Ac^x
import com.adt.bo.Result; ~GZpAPg*
import com.adt.dao.UserDAO; 2%F!aeX
import com.adt.exception.ObjectNotFoundException; N)H
_4L
import com.adt.service.UserManager; ek3,ss3
^w*$qzESy
/** Zc Y* TGx
* @author Joa 21\t2<"
*/ !O-9W=NJ
publicclass UserManagerImpl implements UserManager { Skn2-8;10
v%6mH6V
private UserDAO userDAO; :n t\uwh
g9$P J:
/** hy?e?^
* @param userDAO The userDAO to set. kbF+aS
*/ NDv_@V(D
publicvoid setUserDAO(UserDAO userDAO){ )Ap0" ?q
this.userDAO = userDAO; V;}6C&aP.
} KKLW-V\6K
Rw9 *!<Izt
/* (non-Javadoc) BDCFToSf|
* @see com.adt.service.UserManager#listUser V.k2t$@
XK 09x1r
(org.flyware.util.page.Page) z8"(Yy7m
*/ 9?xc3F2EBD
public Result listUser(Page page)throws \X?GzQkr
^.f`6 6/
HibernateException, ObjectNotFoundException { ^%:syg_RM[
int totalRecords = userDAO.getUserCount(); ==z,vxr
if(totalRecords == 0) Z$'483<
throw new ObjectNotFoundException OVE5:)$x
:O(<3"P/
("userNotExist"); s[HQq;S
page = PageUtil.createPage(page, totalRecords); [8J/#!B
List users = userDAO.getUserByPage(page); )K+Tvx3(m
returnnew Result(page, users); (VxWa#P
} Vg+jF!\7
iKu~o.yy
} @aC2]
`vijd(a?v
~Uet)y<
oy)'wb~
Pd[&&!+gV
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 itg
PG
, Q5Z<\
询,接下来编写UserDAO的代码: !] -ET7
3. UserDAO 和 UserDAOImpl: X+*"FKm S.
java代码: z&@Vg`w"
w u
u0vq`5L
/*Created on 2005-7-15*/ MiX*PqNTM
package com.adt.dao; ct3^V M&/
=h{jF7
import java.util.List; X!w&ib-
wv eej@zs
import org.flyware.util.page.Page; n #|p R2
3;h%mkKQ+
import net.sf.hibernate.HibernateException; \D]H>i$
Rf~? u)h1
/**
oq>8
* @author Joa xqua>!mqS
*/ {{\
d5CkX
publicinterface UserDAO extends BaseDAO { pM^r8kIH
zeZ}P>C
publicList getUserByName(String name)throws *&\fBi]
#)r
HibernateException; {J}Zv5
}gr6naz
publicint getUserCount()throws HibernateException; q-;z!iq|!
C6 XZZ
publicList getUserByPage(Page page)throws -0{"QhdE%
j(;o
HibernateException; _qPd)V6yb
^j1WF[GiSO
} lR9~LNK?
\Q5Jg
,/qS1W(
D\Nhq Vw
A{!D7kwTz~
java代码: ;DkX"X+
Y;L,}/[
`V;vvHP A
/*Created on 2005-7-15*/ 'WA]DlO
package com.adt.dao.impl; *c[X{
XSu9C zx&I
import java.util.List; Wn9b</tf
S$Cht6m
import org.flyware.util.page.Page; &D|wc4+
42Gv]X
import net.sf.hibernate.HibernateException; "t{|e6
import net.sf.hibernate.Query; fgg;WXcT ~
-<'&"-
import com.adt.dao.UserDAO; >4zH\T!
#_,
l7q8U
/** $YmD;
* @author Joa >q:0w{.TU
*/ RK*ZlD<
public class UserDAOImpl extends BaseDAOHibernateImpl dh~+0FZ{A
tWNz:V
implements UserDAO { d +]Gw
8mCL3F
/* (non-Javadoc) ~[por
* @see com.adt.dao.UserDAO#getUserByName 4;*o}E
{hr+ENgV
(java.lang.String) Wa8?o~0"L
*/ `xO9xo#
publicList getUserByName(String name)throws ?W %9H\;
%U.aRSf/
HibernateException { \eD{bD
String querySentence = "FROM user in class oWZbfR9R
BtyBZ8P;e
com.adt.po.User WHERE user.name=:name"; k-v@sb24_
Query query = getSession().createQuery s4$Z.xwr
BJM_kKH
(querySentence); oM=Ltxv}
query.setParameter("name", name); xJvM
l`2;
return query.list(); QT5,_+ho
} K#B)@W?9
M-Az2x;6
/* (non-Javadoc) <fJ*{$[p
* @see com.adt.dao.UserDAO#getUserCount() tr]=q9
*/ YlZe
publicint getUserCount()throws HibernateException { }NQ{S3JW
int count = 0; QT;mCD=OD
String querySentence = "SELECT count(*) FROM /A U&
X
FQbF)K~e
user in class com.adt.po.User"; +$eEZ;4
Query query = getSession().createQuery Yxal%
xp395ub6
(querySentence); .@Z-<P"
count = ((Integer)query.iterate().next fE\;C bi
2Mc}>UI?eO
()).intValue(); t\hvhcbL
return count; \X=?+|
9
} Z2yZz:.'
"]%.%$
/* (non-Javadoc) 9tW=9<E
* @see com.adt.dao.UserDAO#getUserByPage Yy4?|wVl
F 8\nAX
(org.flyware.util.page.Page) *Ge2P3
*/ D(MolsKc?
publicList getUserByPage(Page page)throws ?lh
`>v
6#/Riu%
HibernateException { L}bS"=B[&W
String querySentence = "FROM user in class ? jywW$
<c[+60p"
com.adt.po.User"; #6[7q6{4
Query query = getSession().createQuery k{/2vV[`]
{xm^DT
(querySentence); +gG6(7&+=
query.setFirstResult(page.getBeginIndex()) V@0Z\&
.setMaxResults(page.getEveryPage()); QMGMXa
return query.list(); S
C8r.
} 7b,5*]oZ
: QK )Ym
} qwlIz/j
7|A9
FK
MuRy|
PYldqY
T@[(FVA N
至此,一个完整的分页程序完成。前台的只需要调用 OY'490
sLE@Cm]k
userManager.listUser(page)即可得到一个Page对象和结果集对象 "y_A xOH
Rc2| o.'y
的综合体,而传入的参数page对象则可以由前台传入,如果用 C3Mr)
5B[kZ?>
webwork,甚至可以直接在配置文件中指定。 a'f0Wv0%"
@za X\
下面给出一个webwork调用示例: "o
+" Jd
java代码: #C+""qm
S!0ocS!t
{wWh;
/*Created on 2005-6-17*/ H7 acT
package com.adt.action.user; FcnSO0G%
%4:tRF
import java.util.List; s6k,'`.
CD\k.
import org.apache.commons.logging.Log; ]XX8l:+
import org.apache.commons.logging.LogFactory; BJgg-z{Y
import org.flyware.util.page.Page; IS;F9{
[KIK}:
import com.adt.bo.Result; -G<$wh9~3
import com.adt.service.UserService; l4oI5)w
import com.opensymphony.xwork.Action; @\,WJmW
V j\1HQ
/** .6Swc?
* @author Joa &8R %W"<K
*/ g{&a|NU^
publicclass ListUser implementsAction{ VXforI
B_w;2ZuA
privatestaticfinal Log logger = LogFactory.getLog m^dKww
)NeI]p
(ListUser.class); VmLV:"P}^
AP=mj
private UserService userService; _w+ix9Fr?
2| u 'J
private Page page; 9/OB!<*V|
krkRP%jy
privateList users; c?i=6CdD'
73?ZB+\)0A
/* ^
q]BCOfJ(
* (non-Javadoc) GWZ0!V
* Ds|/\cI$%a
* @see com.opensymphony.xwork.Action#execute() vpOn0([hS
*/ 4&IBNc,sn
publicString execute()throwsException{ j_PICv*6
Result result = userService.listUser(page); K'[H`x^
page = result.getPage(); Fx']kn9
users = result.getContent(); ^E&':6(
return SUCCESS; FHVZ/ e
} @,i_
KN6C
o/EA%q1
/** 8UArl3
* @return Returns the page. ,5" vzGLJ
*/ = :rR%L!a
public Page getPage(){ IS0RhtGy/
return page; ~c7}eTJd"
} S_cba(0-|\
EB'(%dH
/** O/M\Q
* @return Returns the users. wrq0fHwM
*/ /g3U,?qP
publicList getUsers(){ lgTavs
return users; f/G
YDat
} CLI!( 8ZW
vS%r_gf(
/** ;L.@4b[lP
* @param page J2_D P
* The page to set. T_CYSS|fX
*/ s$e0;C!D
publicvoid setPage(Page page){ @)m H"u!(7
this.page = page; K1O0/2O
} |,F/_
)P\Vd #
/** ,mH2S/<}S
* @param users ]Lq9Ompf(t
* The users to set. cCN[c)[c|
*/ L_uliBn
publicvoid setUsers(List users){ O#Ab1FQn
this.users = users; \?)@
#Qs
} 6P;JF%{J
N<ww&GXBX
/** \k;)m-0bj{
* @param userService ou6|;*>d
* The userService to set. IbAGnl {
*/ $-9m8}U(Y
publicvoid setUserService(UserService userService){ R?g
qPi-
this.userService = userService; SlvQ)jw%
} 3e$&rpv
} /)?]vKMiI
B3uv>\
4`uI)N(}*
| Euf:yWY
c,;-[sn
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, z-nhL=
S5]rIcM
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 s<x2*yVUA
?}y?e}y*xZ
么只需要: uN V(r"
java代码: pulE6T7x
CZg$I&x
h0`@yo
<?xml version="1.0"?> uZ*;%y nQ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork niY9`8
='<0z?Af
1.0//EN" "http://www.opensymphony.com/xwork/xwork- rWI6L3,i+
C#X|U2$
1.0.dtd"> =if5$jE3
qJ!&H
<xwork> D 4^2F(YRX
hh`7b ,+ 4
<package name="user" extends="webwork- ?fcQd6-}
5'gV_U
interceptors"> 4'bup h1(
y)?Sn
<!-- The default interceptor stack name DOiL3i"H
"Q;n-fqf
--> I$v*SeVHE
<default-interceptor-ref !q!.OQ
4)ez0[i$X
name="myDefaultWebStack"/> * 3mF.^
A?'Tigi
<action name="listUser" <<K G S
ve_TpP
class="com.adt.action.user.ListUser"> Js[dT|>.
<param I:[^><?E
HkFoyy
name="page.everyPage">10</param> ]cLO-A
<result dM8`!~#&PI
82Dw,Cn
name="success">/user/user_list.jsp</result> ?n9gqwO
</action> m[,!
orq
77"'?
</package> x\!Q[
w N9I )hB
</xwork> V9f$zjpw
@#$5_uU8\(
i/`N~r
Q)S0z2
[f,; +Ze
I5PI;t+
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 y`!~JL*
l -us j%\
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。 ~#+ Hhc(
^c"
wgRHc<
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 oF[l<OY4
fF37P8Ir
AdDlS~\?
XOK.E&eilj
Lgl%fO/<t
我写的一个用于分页的类,用了泛型了,hoho $lmGMljF
CL oc
java代码: %_N-~zZ1E
o_hk!s^4m
cXu"-/
package com.intokr.util; 8%v1[Wi
dUiv+K)ccQ
import java.util.List; X8aNl"x
v1wMXOR
/** !2>MaV1,
* 用于分页的类<br> JJ_77i
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ,;9byb
* z/yNFY]i
* @version 0.01 %7WGodlXW
* @author cheng *^+8_%;1
*/ qELy'\
public class Paginator<E> { s
8O"U%
privateint count = 0; // 总记录数 :^7/+|}9p
privateint p = 1; // 页编号 ]pC/6'
privateint num = 20; // 每页的记录数 W=j
privateList<E> results = null; // 结果 H.#<&5f
R@_i$Df|
/**
c+P.o.k;
* 结果总数 #wn`choT'
*/ J+tpBPmb
publicint getCount(){ dV(61C0wn
return count; T@0\z1,~S
} cC@B\Q
k4Ed 7T-
publicvoid setCount(int count){ <RQ\nU
this.count = count; DY| s|:d
} {1a%CsCM
!0Hx1I<*x
/** :(gZ\q">k
* 本结果所在的页码,从1开始 &0A^_Z .nA
* z.EpRJn
* @return Returns the pageNo. ZdQt!
*/ *V}T}nK7
publicint getP(){ M{:}.H<a
return p; _)AX/%^%
} ##Jg>HL'
xfYDjf :<
/** Bo.< 4P
* if(p<=0) p=1 znm3b8ns
* v%8.o%G
* @param p Bg.~#H
*/ &|cg`m
publicvoid setP(int p){ GcXh
V
if(p <= 0) F2jZ3[P
p = 1; l!z)gto
this.p = p; ~wtl\-cY
} iK&s_}i:
"SGq$3D
/** Fo
K!JX*
* 每页记录数量 X.^S@3[
*/ i> }P V
publicint getNum(){ i}d^a28
return num; a'3|EWS
?
} K1i@.`na/$
B.)!zv\{
/** 53>y<
* if(num<1) num=1 tS|gQUF17
*/ ,ru2C_LQ
publicvoid setNum(int num){ PX7@3Y
if(num < 1) X)P;UVR0
num = 1; [N]5)n
this.num = num; S3Q^K.e?
} `1;m:,9
!kAjne8]d
/** E8$k}I
* 获得总页数 tkQ#mipAj
*/ SvE3E$*
publicint getPageNum(){ !$}:4}56F
return(count - 1) / num + 1; <UI^~Azc#
} 2/[J<c\G
f,S,35`qa
/** <:(pnw*L
* 获得本页的开始编号,为 (p-1)*num+1 0^?:Zds
*/ U7GgGMw
publicint getStart(){ L-J 7z+{
return(p - 1) * num + 1; aNd6#yU$
} A5U//y![{
S}QvG&c
/** mar6/*`I#+
* @return Returns the results. B4fMD]
*/ (6b*JQ^^
publicList<E> getResults(){ uO=yQ&
return results; hn-+]Y:
} *2nQZ^c.
<]{$XcNm
public void setResults(List<E> results){ e,*E`ol
this.results = results; [w>T.b
} ]yg3|C;
&A}@@d
public String toString(){ Q7V*~{
StringBuilder buff = new StringBuilder $q}zW%
=t@8Y`9w
(); )Q:.1Hgl
buff.append("{");
e u{
buff.append("count:").append(count); M`_RkDmy<
buff.append(",p:").append(p); Tf0"9
buff.append(",nump:").append(num); H rMH
buff.append(",results:").append ..Q$q2.
h!@t8R
(results); "e)C.#3
buff.append("}"); \&[Jtv *
return buff.toString(); NOzAk%s3I
} |DB7o+4
cD&Q