Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ZUyS+60
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 f+cN'jH
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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 ~'V&[]nh8
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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 A"e4w?
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分页支持类: z''ejq
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java代码: o%b6"_~%3
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package com.javaeye.common.util; XS}-@5TI
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import java.util.List; )x,/+R]{8l
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publicclass PaginationSupport { u`.3\Geh
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publicfinalstaticint PAGESIZE = 30; SK5_^4
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privateint pageSize = PAGESIZE; f, '*f:(
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privateList items; Z%Pv,h'Q
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privateint totalCount; *HsA.W~2W
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privateint[] indexes = newint[0]; PNz]L
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privateint startIndex = 0; {?;qy\m]o
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public PaginationSupport(List items, int iT;Ld $!{f
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totalCount){ VFrp7;z43
setPageSize(PAGESIZE); v8YF+N
setTotalCount(totalCount); p,V%wGM
setItems(items); k|czQ"vaI
setStartIndex(0); zcC:b4
} =]r2;014
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public PaginationSupport(List items, int cL<,]%SkE
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totalCount, int startIndex){ RWRqu }a
setPageSize(PAGESIZE);
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setTotalCount(totalCount); .Y|wG<E
setItems(items); m-6&-G#
setStartIndex(startIndex); A0>r]<y
} i&1rf |
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public PaginationSupport(List items, int Gshy$'_e
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totalCount, int pageSize, int startIndex){ a/v]E]=qI
setPageSize(pageSize); E/hT/BOPK
setTotalCount(totalCount); QH,Fw$1
setItems(items); x=Aq5*A0
setStartIndex(startIndex); .l hS
} ,1g_{dMx
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publicList getItems(){ aX~Jk >a0
return items; 76o3Sge:
} 7|o!v);uR
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publicvoid setItems(List items){ a)4%sX*I
this.items = items; .EPv4[2%F8
} Qqi?DW1)-
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publicint getPageSize(){ Uqz.Q\A
return pageSize; QI'-I\Co
} )@p?4XsT4J
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publicvoid setPageSize(int pageSize){ Q_Br{
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this.pageSize = pageSize; M KX+'p\w
} LzJ`@0RrX
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publicint getTotalCount(){ ,N_/J4Us
return totalCount; wMw}3qX$j
} U {Knjo S
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publicvoid setTotalCount(int totalCount){ Y]=k"]:%
if(totalCount > 0){ "hQGk
this.totalCount = totalCount; cRMyYd J o
int count = totalCount / :
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pageSize; 0Vrs bkS
if(totalCount % pageSize > 0) Z^}[CQ&Am
count++; {/(.Bpld
indexes = newint[count]; (t\U5-w
for(int i = 0; i < count; i++){ 'Hzc"<2Y\
indexes = pageSize * $hHV Ie]+
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} Q)y5'u qZ
}else{ mo3A *|U
this.totalCount = 0; m ?; ?I]`
} sYo&@~T
} 7AS_Aw1L
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publicint[] getIndexes(){ MRw4?HqB
return indexes; B;F~6i
} :h |]j[2p
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publicvoid setIndexes(int[] indexes){ w[D]\>QHa
this.indexes = indexes; p!~1~q6
} D)pTE?@W'
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publicint getStartIndex(){ vBJxhK-
return startIndex; 8MI8~
} uO-|?{29
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publicvoid setStartIndex(int startIndex){ g~b$WV%
if(totalCount <= 0) @ZjO#%Ep/
this.startIndex = 0; $=Ns7Sbup
elseif(startIndex >= totalCount) zd)QCq
this.startIndex = indexes ?G,gPb
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[indexes.length - 1]; =-_hq'il
elseif(startIndex < 0) UX[s5#
this.startIndex = 0; FF#+d~$z
else{ ^<qi&*
this.startIndex = indexes t1 U+7nM
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[startIndex / pageSize]; \K~wsu/?`
} MoQ\~/Z|
} <YtjE!2
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publicint getNextIndex(){ J^ewG
int nextIndex = getStartIndex() + 7H?xp_D
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pageSize; yNEU/>]>2
if(nextIndex >= totalCount) ~,ozhj0f/
return getStartIndex(); $|@vmv0
else m(?{#aaq
return nextIndex; b1cVAfUP
} W1M322]>L
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publicint getPreviousIndex(){ F81EZ/
int previousIndex = getStartIndex() - N6of$p'N
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pageSize; M2w'cdHk
if(previousIndex < 0) 9&uf
return0; 09anQHa
else Z)$@1Q4P?1
return previousIndex; QK#wsw
} nw%9Qw
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} 'Etq;^H
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抽象业务类 ppNMXbXR
java代码: NN=^4Xpc:
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/** GM'yOJo
* Created on 2005-7-12 Y I;iG[T,&
*/ Hnk&2bY
package com.javaeye.common.business; >;hAw!|#
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import java.io.Serializable;
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import java.util.List; ~Ck OiWC0
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import org.hibernate.Criteria; jLt3jN
import org.hibernate.HibernateException; LtX53c
import org.hibernate.Session; e2NK7
import org.hibernate.criterion.DetachedCriteria; v\4<6Z:4
import org.hibernate.criterion.Projections; pvUV5^B(M
import jq*`| m;Q
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org.springframework.orm.hibernate3.HibernateCallback; pvsa?z;rP
import M*ZN]9{^.
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org.springframework.orm.hibernate3.support.HibernateDaoS r
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upport; 5|*`} ;/y
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import com.javaeye.common.util.PaginationSupport; z8awND
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public abstract class AbstractManager extends uOeal^uS
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HibernateDaoSupport { @-Ql6k
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privateboolean cacheQueries = false; Jj+Q2D:
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privateString queryCacheRegion; 2;WbXc!#!
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publicvoid setCacheQueries(boolean irD5;xk([
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cacheQueries){ -ycYQ~R
this.cacheQueries = cacheQueries; ERIMz,
} th[v"qD9G
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publicvoid setQueryCacheRegion(String k:run2K
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queryCacheRegion){ 6{]F#ig=
this.queryCacheRegion = 0>7Ij7\[8
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queryCacheRegion; ~[t#$2d}
} ` qs}L
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publicvoid save(finalObject entity){ A|
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getHibernateTemplate().save(entity); wV==sV
} o4WQA"VxM
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publicvoid persist(finalObject entity){ k%cE8c}R;A
getHibernateTemplate().save(entity); .cQO?UKK
} Wy7w zt
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publicvoid update(finalObject entity){ <n]P D;.4
getHibernateTemplate().update(entity); v;o1c44;
} k Alxm{
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publicvoid delete(finalObject entity){ (vZ-0Ep}
getHibernateTemplate().delete(entity); m
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} Uc {m##!
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publicObject load(finalClass entity, xt?-X%oY8
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finalSerializable id){ rN}8~j
return getHibernateTemplate().load bc'IoD/
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(entity, id); ,.QJS6Yv
} ^_Hf}8H7]
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publicObject get(finalClass entity, GT<oYrjU
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finalSerializable id){ }`<&l
return getHibernateTemplate().get
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(entity, id); A|r3c?q
} Tt)z[^)%
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publicList findAll(finalClass entity){ *7h~0%WR
return getHibernateTemplate().find("from b+|Jw\k
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" + entity.getName()); ~#3{5*
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} -[-oz0`Sl{
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publicList findByNamedQuery(finalString T[|#DMg$F
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namedQuery){ kx;X:I(5&P
return getHibernateTemplate 3?*dv14
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().findByNamedQuery(namedQuery); HD=F2p
} baII!ks
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publicList findByNamedQuery(finalString query, )C8^'*!
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finalObject parameter){ cr!W5+r
return getHibernateTemplate Jh
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().findByNamedQuery(query, parameter); R<&Euph
} +ausm!~6
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publicList findByNamedQuery(finalString query, <x^$Fu
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finalObject[] parameters){ fAULuF
return getHibernateTemplate -`k>(\Q<d
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().findByNamedQuery(query, parameters); F5Xb_&
} nd8<*ru$
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publicList find(finalString query){ rS BI'op
return getHibernateTemplate().find A{zqr^/h
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(query); @ar%`+_
} \
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publicList find(finalString query, finalObject D j9aTO
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parameter){ kuH%aM<R
return getHibernateTemplate().find QAV6{QShj
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(query, parameter); kT@ITA22
} I+& T}R
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public PaginationSupport findPageByCriteria lz0-5z+\
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(final DetachedCriteria detachedCriteria){ 6LDZ|K@
return findPageByCriteria !
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); _s^tL2Pc
} h.vy SwF"j
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public PaginationSupport findPageByCriteria vMp=\U-~^
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(final DetachedCriteria detachedCriteria, finalint %1A8m-u]M
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startIndex){ ,/+Mp
return findPageByCriteria lm4A%4-db
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(detachedCriteria, PaginationSupport.PAGESIZE, W/2y;@
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startIndex); FFw(`[A_
} +yO) 3
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public PaginationSupport findPageByCriteria kC.dJ2^j+
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(final DetachedCriteria detachedCriteria, finalint CB#2XS>V
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pageSize, fYP,V0P
finalint startIndex){ fF0K].
return(PaginationSupport) Y5GN7.
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getHibernateTemplate().execute(new HibernateCallback(){ ejV`W7U
publicObject doInHibernate YdCl
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(Session session)throws HibernateException { j-1V,V=
Criteria criteria = ~%*l>GkP*
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detachedCriteria.getExecutableCriteria(session); "QOQ
int totalCount = g4WmUV#wp
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((Integer) criteria.setProjection(Projections.rowCount ;&j'`tP
>k"O3Pc@
()).uniqueResult()).intValue(); SdlO]y9E
criteria.setProjection B1}i0pV,,
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(null); epnZGz,A
List items = T/|!^qLF
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criteria.setFirstResult(startIndex).setMaxResults _ooHB>sH
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(pageSize).list(); B@-\.m
PaginationSupport ps = 7RUztu\_
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new PaginationSupport(items, totalCount, pageSize, J8~hIy6]
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startIndex); cY!Y?O
return ps; \5}PF+)|
} ;b [>{Q;
}, true); =r/K#hOR\J
} @-)S*+8
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public List findAllByCriteria(final %@:>hQ2;
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DetachedCriteria detachedCriteria){ `S((F|Ty=;
return(List) getHibernateTemplate z\tY A
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().execute(new HibernateCallback(){ zKP[]S-
publicObject doInHibernate ]CP5s5
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(Session session)throws HibernateException { s&ox%L4
Criteria criteria = &G%AQpDW5
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detachedCriteria.getExecutableCriteria(session); ^iEf"r
return criteria.list(); dwB#k$VIOw
} "#wAGlH6>
}, true); +DSbr5"VlB
} Qf0P"s`
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public int getCountByCriteria(final aN"YEL>w
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DetachedCriteria detachedCriteria){ Q%aF~
Integer count = (Integer) R~oY
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getHibernateTemplate().execute(new HibernateCallback(){ ,'c%S|]U7
publicObject doInHibernate T+XcEI6w
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(Session session)throws HibernateException { eW.qMx#:od
Criteria criteria = z&!o1uq
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detachedCriteria.getExecutableCriteria(session); _~Od G
return aEdMZ+P.
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criteria.setProjection(Projections.rowCount d
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()).uniqueResult(); ){GJgk|P
} /w dvm4
}, true); &S.p%Qe"
return count.intValue(); ;,Vdj[W$>
} 9hK8dJw
} Qq{tX
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用户在web层构造查询条件detachedCriteria,和可选的 \t{4pobo
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 d.ywH;
@ ~{TL
PaginationSupport的实例ps。 FBP #_"z
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ps.getItems()得到已分页好的结果集 ZD50-w;
ps.getIndexes()得到分页索引的数组 :Dr4?6hdr
ps.getTotalCount()得到总结果数 CNuE9|W(vI
ps.getStartIndex()当前分页索引 b?=r%D->w
ps.getNextIndex()下一页索引 Sy.%>$ z
ps.getPreviousIndex()上一页索引 )+G0m,n
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 6;Izw$X
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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
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一下代码重构了。 1\-lAk!
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我把原本我的做法也提供出来供大家讨论吧: )jI4]6
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首先,为了实现分页查询,我封装了一个Page类: WZA1nzRc
java代码: Yo5ged]i
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/*Created on 2005-4-14*/ brE%/%!e
package org.flyware.util.page; !`U #Pjp.
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/** 2DZ&g\|
* @author Joa YS9)%F=X
* 'bji2#z[
*/ UT_t]m
publicclass Page { <1sUK4nQ,
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/** imply if the page has previous page */ R $/q=*k
privateboolean hasPrePage; Nde1`W]:
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/** imply if the page has next page */ ('_S1?y
privateboolean hasNextPage; ^s8JW" H
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/** the number of every page */ Q Na*Y@i
privateint everyPage; R8% u9o
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/** the total page number */ k3
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privateint totalPage; \>/AF<2"
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/** the number of current page */ {yBd{x<>/
privateint currentPage; @$ )C pg
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/** the begin index of the records by the current cJ,`71xop,
"g!/^A!!
query */ 9zehwl]~
privateint beginIndex; gcM(K.n
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/** The default constructor */ =:RNpi,
public Page(){ :d~&Dt<c
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} b!;WF
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/** construct the page by everyPage Z!?T&:
* @param everyPage j~ qm5}
* */ Mb%[Qp60
public Page(int everyPage){ w^$$'5=
this.everyPage = everyPage; dfeN_0`-
} B<!wh
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/** The whole constructor */ #
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public Page(boolean hasPrePage, boolean hasNextPage, xiQd[[(sM
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int everyPage, int totalPage, L!W5H2Mc
int currentPage, int beginIndex){ 'Ya- ;5Y]
this.hasPrePage = hasPrePage; KU0;}GSNX}
this.hasNextPage = hasNextPage;
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this.everyPage = everyPage; cmLI!"RLe
this.totalPage = totalPage; apm,$Vvjy
this.currentPage = currentPage; 6;\Tps;A
this.beginIndex = beginIndex; hcD.-(-;)
} }Tk*?tYt
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/** e]d\S]5
* @return Q mz3GH@wg
* Returns the beginIndex. -F-,Gcos
*/ k:E+]5
publicint getBeginIndex(){ kh*td(pfP9
return beginIndex; FwSV
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} QtqE&j
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/** SL%
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* @param beginIndex h6gtO$A|p=
* The beginIndex to set. ]FO)U
*/ *7/MeE6)i
publicvoid setBeginIndex(int beginIndex){ I#t#%!InH
this.beginIndex = beginIndex; u&Y1,:hiL
} C'0=eel[
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/** x@"`KiEUs
* @return 7y>{Y$n
* Returns the currentPage. Yh;A
*/ .*w3 ryQ
publicint getCurrentPage(){
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return currentPage; E@ !~q
} ;ZLfb n3\
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/** T;JA.=I
* @param currentPage ,Z]4`9c
* The currentPage to set. :j!N7c{
*/ +QFY.>KH
publicvoid setCurrentPage(int currentPage){ h`p9H2}0
this.currentPage = currentPage; q"^T}d d,
} 2Y{r2m|o
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/** '4d+!%2t
* @return qeZ*!H6-
* Returns the everyPage. u'EzYJ7
*/ ~bk+JK- >
publicint getEveryPage(){ c`G~.paY|
return everyPage; V4
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} >5=uq
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/** qw%wyj7
* @param everyPage +q4AK<y-
* The everyPage to set. wpPCkfPyL
*/ 5U&?P
publicvoid setEveryPage(int everyPage){ 'uA$$~1
this.everyPage = everyPage; mq~L1<f
} *6%r2l'kZ
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/** d#G H4+C
* @return |yow(2(F@
* Returns the hasNextPage. 0xg6
*/ e!~x-P5M`
publicboolean getHasNextPage(){ |#!P!p}
return hasNextPage; wNm~H
} T8rf+B/.L
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/** ,t_Fo-i7vI
* @param hasNextPage 0FD+iID
* The hasNextPage to set. WKPuIE:
*/ c 7uryL
publicvoid setHasNextPage(boolean hasNextPage){ A `n:q;my
this.hasNextPage = hasNextPage; kUG3_ *1
.
} .!hB tR
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/** {n>W8sN<
* @return pI|H9
* Returns the hasPrePage. BWN[>H %S
*/ S7
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publicboolean getHasPrePage(){ (Q09$
return hasPrePage; FO5'<G-
} !EQMTF=(
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/** <+c6CM$#}V
* @param hasPrePage 7&z`N^dz{
* The hasPrePage to set. "ewB4F[
*/ 9>"To
publicvoid setHasPrePage(boolean hasPrePage){ kdrya
this.hasPrePage = hasPrePage; M%8:
} h0fbc;l
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/** FWbA+{8
* @return Returns the totalPage. _=eeZ4f
* aGz<Yip
*/ UE9r1g`z
publicint getTotalPage(){ wN
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return totalPage; bJE$>
} M6b;
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/** a~F`{(Q2
* @param totalPage t~0}Emgp<(
* The totalPage to set. woqP&8a
*/ wz P")}[0
publicvoid setTotalPage(int totalPage){ "sf]I[a
this.totalPage = totalPage; `)W}4itm
} {s=$.Kg
w<]Wg^dyQ
} 8HyK;+ZkVd
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wb
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 kOGpe'bV
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个PageUtil,负责对Page对象进行构造: 3wBc`vJ!
java代码: 2ajQ*aNq
MyOdWD&7
b)A$lP%`
/*Created on 2005-4-14*/ @"m?
#
package org.flyware.util.page; IYy2EK[s
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import org.apache.commons.logging.Log; o|nj2 .
import org.apache.commons.logging.LogFactory; hD>O LoO
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/** ;ml;{<jI
* @author Joa )up!W4h6o
* TY=BP!s
*/ Q
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publicclass PageUtil { `q
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ba 3_55]
privatestaticfinal Log logger = LogFactory.getLog *p.P/w@1
yp=2nU"o
(PageUtil.class); MOFIR
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/** pt;kN&A^
* Use the origin page to create a new page Ve&(izIh
* @param page m.MOn3n]
* @param totalRecords X}yEMe{T
* @return XY5I5H_U
*/ J0}OmNTzD
publicstatic Page createPage(Page page, int RkN a;j)t
7 3k3(rZ
totalRecords){ $o`N% ]
return createPage(page.getEveryPage(), eD* "#O)W
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page.getCurrentPage(), totalRecords); +[JGi"ca
} .( vS/
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/** '$M=H.
* the basic page utils not including exception :Q\b$=,:
Xv'M\T}6C+
handler bf
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* @param everyPage DB yRP-TH
* @param currentPage +>oVc\$
* @param totalRecords aT#R#7<Eg
* @return page 5w`v
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*/ !V.'~xj
publicstatic Page createPage(int everyPage, int S)GWr"m-
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currentPage, int totalRecords){ !9i,V{$c`"
everyPage = getEveryPage(everyPage); :<s)QD
currentPage = getCurrentPage(currentPage); +EcN[-~
int beginIndex = getBeginIndex(everyPage, Od'!v &
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currentPage); 9[|Ql
int totalPage = getTotalPage(everyPage, Pe/cwKCI
zQ}:_
totalRecords); im_W0tGvF
boolean hasNextPage = hasNextPage(currentPage, S >uzW #
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totalPage); "j9,3yJT
boolean hasPrePage = hasPrePage(currentPage); JLRw`V,o7
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returnnew Page(hasPrePage, hasNextPage, VuFH
>8n
everyPage, totalPage, e.i5j^5u
currentPage, UR?[ba_h
iwL\H a
beginIndex); `7Ni bZX0
} dKw*L|5
r}9qK%C G.
privatestaticint getEveryPage(int everyPage){ 4)iSz>
return everyPage == 0 ? 10 : everyPage; :t]YPt
} -ny[Lh^b
$CO^dFf
privatestaticint getCurrentPage(int currentPage){ U\y];\~H
return currentPage == 0 ? 1 : currentPage; [[?:,6I
} RNiZ2:
cp2e,%o
privatestaticint getBeginIndex(int everyPage, int zHr1FxD
lx~!FLn
currentPage){ Ud:v3"1
return(currentPage - 1) * everyPage; rU5gQq;
} C]-Z+9Vvv
OUe@U;l{Z
privatestaticint getTotalPage(int everyPage, int Rw*l#cr=.
?K{CjwE.M
totalRecords){ c0u!V+V%
int totalPage = 0; f>5{SoM
$\$5::}r
if(totalRecords % everyPage == 0) b3x!tuQn
totalPage = totalRecords / everyPage; 8OZc:/
else U=p,drF,A
totalPage = totalRecords / everyPage + 1 ; [a5L WW
NZ'S~Lr
return totalPage; ~jmHzFkQ
} J
\1&3r|R
eM+]KG)}
privatestaticboolean hasPrePage(int currentPage){ xe2Ap[Y'M
return currentPage == 1 ? false : true; _;{n+i[
} (D{Fln\
J(h=@cw
privatestaticboolean hasNextPage(int currentPage, 9~<HTH
(H<S&5[
int totalPage){ "Sc_E}q|e
return currentPage == totalPage || totalPage == Ta%{Wa\U9z
xRJv_=dT
0 ? false : true; "Q#/J)N
} 'i{kuTv
d5%A64?
"MKgU[t
} "o`N6@[w^
8,#v7ns}#
;_,=
g` 6Xrf
%.BbPR 7?h
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 a{QHv0goG
%s%v|HDs
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 AIF?+i%H}
fEWS3`Yy
做法如下: pA+W
8v#*
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 sbrU;X_S
x;l\#x/<
的信息,和一个结果集List: "ZNiTND
java代码: &|IY=$-
^{_`jE
<jQ?l%\
/*Created on 2005-6-13*/ 9@#Z6[=R,
package com.adt.bo; u} JL*}Q
v}IkY
import java.util.List; ngcXS2S_
?3Se=7
k
import org.flyware.util.page.Page; j>+x|!k
+T+f``RcK
/** =E8lpN'
* @author Joa g9H~\w
*/ kV(}45i]s
publicclass Result { 9l@VxX68M
f[HhLAVGK`
private Page page; }L{en
ync2X{9D
private List content; zJOjc/\
G7DEavtr
/** .ZFs+8qU>
* The default constructor n@mWBUM
*/ }>=k!l{
public Result(){ 3205gI,
super(); [2gK^o&t
} @|6n.'f+
x^qmYX$'1b
/** =M>1;Qr<Z/
* The constructor using fields D%N^iJC,9
* =2BGS\$#
* @param page j#"?Oe{_1
* @param content t(-noy)
*/ GN /]^{D
public Result(Page page, List content){ YBN@{P$
this.page = page; _p\
this.content = content; qgvg
MWj
} L@2T
}a,j1r_Hl&
/** <- Q=h?D
* @return Returns the content. FylL7n
*/ (YF`#v6
publicList getContent(){ 'xm _oGWE
return content; SG2s!Ht
} &/d;4Eu
1D&Q{?RM
/** ]vMr@JM-G
* @return Returns the page. M%7{g"J*
*/ 9Ruj_U
public Page getPage(){ y5 $h
return page; ZMy0iQ@
} d_BECx<\
YgNt>4K
/** +N:K V}K
* @param content rP>iPDf
* The content to set. 5m!FtHvm1
*/ Cb7f-Eag
public void setContent(List content){
G4vXPx%a8
this.content = content; A,{X<mLFb
} <f &z~y=
Dj'aWyW'
/** X(U
CN0#
* @param page ?~$0;5)QC
* The page to set. )Ge.1B$8h
*/ "~0m_brf
publicvoid setPage(Page page){ V.vA~a
this.page = page; t&T0E.kh*X
} cJd~UQ<k
} rn #FmM
{5QIQ
Q3vC^}Dmr
4d#w}
NJ^`vWi
2. 编写业务逻辑接口,并实现它(UserManager, z 0]K:YV_
6e3s
|
UserManagerImpl) JziuwL5,
java代码: Lg0Vn&k
tT'*Uu5
K9B_o,
/*Created on 2005-7-15*/ ?2zVWZ
package com.adt.service; Fq>=0 )
aN?{MA\
import net.sf.hibernate.HibernateException; ~CgKU8
{L5!_]6
import org.flyware.util.page.Page; hqIYo
.<
N=^{FZ
import com.adt.bo.Result; r63_|~JVB<
55MrsiW
/** [`nY/g:
* @author Joa ")'o5V
*/ YhYcqE8
publicinterface UserManager { 17AJT
Dj}n!M`2I
public Result listUser(Page page)throws .[%em9u
8\+kfK
HibernateException; bwR_ uF
+ntrp='7O7
} P9=L?t.
PXqLK3AE
3^AycwNBA
eL3HX _2(
xdb9oH
java代码: wNMg Y
AuuZWd
np,L39:sf
/*Created on 2005-7-15*/ M3c!SXx\
package com.adt.service.impl; DFKFsu8s
f_a.BTtNO
import java.util.List; Pj9n`LwM
8.FBgZh*
import net.sf.hibernate.HibernateException; )nmLgsg
$zS0]@Dj
import org.flyware.util.page.Page; 86igP
import org.flyware.util.page.PageUtil; ~CiVLSH=
~L $B]\/A5
import com.adt.bo.Result; _i{$5JJ+K2
import com.adt.dao.UserDAO; y`O !,kW
import com.adt.exception.ObjectNotFoundException; m99j]wr~c
import com.adt.service.UserManager; P=PcO>
wQbN5*82
/** 2g5Ft
* @author Joa >Pne@w!*
*/ Se h[".l
publicclass UserManagerImpl implements UserManager { tZ,vt7
u3)Oj7cX
private UserDAO userDAO; KdY3
"S#4
/** ru[W?O"
* @param userDAO The userDAO to set. #-$\f(+<
*/ d\Cx(Lb[
publicvoid setUserDAO(UserDAO userDAO){ :U)>um34e
this.userDAO = userDAO; [5K&J-W
} $MD|YW5
RU&,z3LEb
/* (non-Javadoc) Gh}k9-L
* @see com.adt.service.UserManager#listUser ,0+%ji^V
V?AHj<
(org.flyware.util.page.Page) >^}nk04
*/
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public Result listUser(Page page)throws ,FRFH8p
V#8]io
HibernateException, ObjectNotFoundException { "8MG[$Y
int totalRecords = userDAO.getUserCount(); ^2Sa_.
if(totalRecords == 0) qj*IKS
throw new ObjectNotFoundException .BN~9w
N!Dc\d=8q]
("userNotExist"); BzBij^h
page = PageUtil.createPage(page, totalRecords); %\6ns
List users = userDAO.getUserByPage(page); P'f0KZL;
returnnew Result(page, users); #;FHyKx
} F7$x5h@
cpz'upVOZ
} Q79& Q04XN
\Y.&G,?
C"l_78
<[{Ty+
BG:l Zj'I
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 6&/H
XqP
p;Ezmz
询,接下来编写UserDAO的代码: v~^c-]4I
3. UserDAO 和 UserDAOImpl: .b]
32Ww
java代码: W+k`^A|@
PZ5BtDm
w5*?P4P
/*Created on 2005-7-15*/ P<P4*cOV
package com.adt.dao; )zw}+z3st
B.w ihJVDg
import java.util.List; V_Z ~$
MgJiJ0y
import org.flyware.util.page.Page; mXZOkx{
@Dc?fyY*o<
import net.sf.hibernate.HibernateException; \2cbZQx
tI50z khaB
/** r,}U-S.w
* @author Joa xK4b(KJj
*/ 9>~UqP9
publicinterface UserDAO extends BaseDAO { T&Dt;CSF
dm3cQ<0
publicList getUserByName(String name)throws j" wX7
YrAaL"20
HibernateException; T' O5>e
}`k >6B
publicint getUserCount()throws HibernateException; J
}izTI
jU')8m[
publicList getUserByPage(Page page)throws Dw}8ci'
:$Lu
V5
HibernateException; gM=oH
M7Ej#Y
} ]{0R0Gr94
yQ\K;
{l&6=z
N<wy"N{iS
zt/p'khP3
java代码: @91Q=S
#6g-{OBv
`>:ozN#)\
/*Created on 2005-7-15*/ 7{=<_
package com.adt.dao.impl; Kj[X1X5
&.k'Dj2hf
import java.util.List; l:NEK`>i
(WT0j
import org.flyware.util.page.Page; }W&hPC
bni :B?#
import net.sf.hibernate.HibernateException; )@DT^#zR
import net.sf.hibernate.Query; aYQ!`mS::M
4-^LC<}k
import com.adt.dao.UserDAO; g Z3VT{
/BC(O[P
/** xLht6%o*
* @author Joa 'A91i
*/ 3UeG>5R
public class UserDAOImpl extends BaseDAOHibernateImpl j^A0[:2
gE8=#%1<
implements UserDAO { S-[]z*
w
<zO
/* (non-Javadoc) x7$U
* @see com.adt.dao.UserDAO#getUserByName $q#|B3N%
x:8x GG9
(java.lang.String) M7vc/E}]n
*/ :b+C<Bp64r
publicList getUserByName(String name)throws 7aTo!T
:32
HibernateException { M ,.++W\
String querySentence = "FROM user in class 9:0JWW^so
`o(PcX3/}
com.adt.po.User WHERE user.name=:name"; e9r#r~Qq|
Query query = getSession().createQuery 2GRh8G&5
uiq)?XUKv
(querySentence); i|u3 Qt5
query.setParameter("name", name); .v[8ie
return query.list(); I^ W
} @DK,ka(
[.tqgU
/* (non-Javadoc) b{H&%Jx)
* @see com.adt.dao.UserDAO#getUserCount() 6L@g]f|Y@
*/ mNw|S*C
publicint getUserCount()throws HibernateException { r.M8#YL
int count = 0; {UT>>
*C
String querySentence = "SELECT count(*) FROM p1t9s
N,
"El$Sat`
user in class com.adt.po.User"; 1fRYXqx
Query query = getSession().createQuery ,ZjbbBZ
+) 2c\1
(querySentence); TL@_m^SM
count = ((Integer)query.iterate().next ?}^e,.M0?s
Q1V 4bmM
()).intValue(); kK!An!9C
return count; u>:sXm
} #tG/{R
X~abn7_
/* (non-Javadoc) |x3(Tf
* @see com.adt.dao.UserDAO#getUserByPage aE.T%xR
!!f)w!wW
(org.flyware.util.page.Page) 7]a6dMh
*/ R:YX{Tq
publicList getUserByPage(Page page)throws !]qwRB$5
CD1}.h
HibernateException { Ty\&ARjb 8
String querySentence = "FROM user in class Nb\4Mv`
A" `62
com.adt.po.User"; h$|K vS
Query query = getSession().createQuery }_}C ^
>L#&L?#
(querySentence); ~]?Q'ER
query.setFirstResult(page.getBeginIndex()) &s_O6cqgh
.setMaxResults(page.getEveryPage()); `9b/Q
return query.list(); k{Yj!C>
#
} 4VLrl8$K
cF_`m
} 5{qFKo"g@,
w'ZL'/d
EL80f>K
O?NAbxkp
lwPK^)|}
至此,一个完整的分页程序完成。前台的只需要调用 I"*g-ji0
/HH5Mn*
userManager.listUser(page)即可得到一个Page对象和结果集对象 (qHI>3tpY
T#?KY
的综合体,而传入的参数page对象则可以由前台传入,如果用 {y=H49
oz%ZEi\bW
webwork,甚至可以直接在配置文件中指定。 "XMTj <D
N8:?Z#z
下面给出一个webwork调用示例: nU%rSASu
java代码: [(}f3W &
6grJoim|
tUv@4<~,/
/*Created on 2005-6-17*/ t`03$&Cx7
package com.adt.action.user; rs2~spN;h
%stZ'IX
import java.util.List; a?E]-Zf
?sDm~]Z
import org.apache.commons.logging.Log; yd5r]6ej
import org.apache.commons.logging.LogFactory; 2?rg&og6
import org.flyware.util.page.Page; 3toY #!1Ch
a9Lf_/w{ &
import com.adt.bo.Result; `7}6
import com.adt.service.UserService; ?rXh
x{vD
import com.opensymphony.xwork.Action; 3(%hHM7DM
!cT#G
/** N5csq(
* @author Joa MzYTEe&-L
*/ K$(&Qx}
publicclass ListUser implementsAction{ 3WS`,}
i}ypEp
privatestaticfinal Log logger = LogFactory.getLog sLzcTGa2:z
t*y4)I !gR
(ListUser.class); HY9H?T
kvv-f9/-
private UserService userService; z~+_sTu
r]Da4G^
private Page page; G+AD
&EHV
j2deb`GD
privateList users; 6'395x_.\
K+Al8L?K_
/* "Q'#V!
* (non-Javadoc) jfZ(5Qu3.H
* ?/)Mt(p
* @see com.opensymphony.xwork.Action#execute() :h0as!2@dp
*/ v>.nL(VLjP
publicString execute()throwsException{ cEi{+rfZd|
Result result = userService.listUser(page); |gx{un`
page = result.getPage(); l/[@1(F
users = result.getContent(); JT&CJ&#[h
return SUCCESS; :1eI"])(
} 6#6Ve$Vl]
mN@)b+~(S
/** C9x'yBDv
* @return Returns the page. nCh9IF[BL/
*/ p=\DZU~1
public Page getPage(){ 4?g~GI3
return page; z|F>+6l"Y7
} tc\LK_@$/F
j{>E.F2.
/** KM< +9`
* @return Returns the users. $&EZVZ{r
*/ W!.UMmw`
publicList getUsers(){ Wt()DG|[
return users; ,W5pe#n
} G{}E~jDi?
NwD*EuPF :
/** 9fMg?
* @param page jpZX5_o
* The page to set. 9z\q_0&i
*/ < Upn~tH
publicvoid setPage(Page page){ 511^f`P<
this.page = page; kf_s.Dedw
} ?,]%V1(@V`
7'7bIaJk
/** 3l->$R]
* @param users kI]i,v#F
* The users to set. pK1P-!c
*/ qi`*4cas*A
publicvoid setUsers(List users){ B@e,3:
this.users = users; *58<.L|
} })g|r9=
|;6FhDW+'
/** ?0hk~8c
* @param userService 5|NM]8^^0[
* The userService to set. l Vo](#W
*/ ]o$Kh$~5
publicvoid setUserService(UserService userService){ 5dT-{c%w4
this.userService = userService; LTS3[=AB
} idvEE6I@
} UB&ofO
b.47KJz t
IpGq_TU
fC.-* r
4o9#B:N]J
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, Y<:%_]]
ktU98Bk]
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 Sq/M
%z5'
ml.l( 6A
么只需要: 6vro:`R ?
java代码: ruS/Yh
})T}e7>T
]2QZ47
<?xml version="1.0"?> qnyFRPC
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork pwT|T;j*
>wej1#\3
1.0//EN" "http://www.opensymphony.com/xwork/xwork- kGc;j8>."
8^\DQ&D
1.0.dtd"> ?'P8H^K6u
xE;4#+_I
<xwork> D@^ r
%FT F
<package name="user" extends="webwork- tNjb{(eO\h
{G&K_~Vj
interceptors"> Tcz67&c |W
uZz^>*b
<!-- The default interceptor stack name Z$X2*k6PK
37?%xQ!
--> T mH#
<default-interceptor-ref jMcCu$i7
f";70}_
name="myDefaultWebStack"/> xVuGeanCv
j +@1frp
<action name="listUser" =y,_FFoS
_:+W0YS
class="com.adt.action.user.ListUser"> (:,N?bg
<param @{@x2'-A
Itr yiU9
name="page.everyPage">10</param> $V]D7kDph*
<result _MR|(mV
D}HW7Hnu^
name="success">/user/user_list.jsp</result> d~g
</action> [Rs5hO
j8M}*1
</package> -x_b^)x~b7
RSG4A>%!mI
</xwork> g (ZeGNV8
^>.?kh9z
t#&^ -;
"%D+_Yb'X
c;Hf +n
$ENA$
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 F&lWO!4
q!7z4Cn
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。
0
!E* >
{ogGi/8
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 D4}WJMQ7s
x/~V
ZO
1oFU4+{ 4
B*zb0hdo:
IJD'0/R'c
我写的一个用于分页的类,用了泛型了,hoho Axk
p
nrUrMnlg
java代码: |D$U{5}Mv
Sl:Qq!
N1\u~%AT"
package com.intokr.util; ]8htJ]<|Q
C;oP"K]4=
import java.util.List; )U>q><
+VdYT6{p
/** isj<lnQ
* 用于分页的类<br> NlU:e}zGR
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 16ke CG\
* q_g'4VZv
* @version 0.01 $T^O3 8$
* @author cheng 8|d lt$
*/ j08G-_Gjn
public class Paginator<E> { FnP/NoZa>
privateint count = 0; // 总记录数 uB
6`e!Q
privateint p = 1; // 页编号 tJUMLn?
privateint num = 20; // 每页的记录数 U/&?rY^|
privateList<E> results = null; // 结果 $ZK4Ps -$
GTYGm
/** D(~6h,=m
* 结果总数 |LcN_,}6
*/ 8/-GrdyE
publicint getCount(){ \kzxt/Ow
return count; G( nT.\
} I=D`:u\H
>
9JzYI^
publicvoid setCount(int count){ _Eq:Qbw#
this.count = count; \$VtwVQ,b
} |C=^:@}ri?
X3!btxa%t
/** bRLmJt98P
* 本结果所在的页码,从1开始 lR{eO~'~V
* ,`P,))
* @return Returns the pageNo. X
z2IAiAs'
*/ 00%$?Fyk
publicint getP(){ 1#(,Bq4
return p; 2OAh7 '8<
} "%A/bv\u
<hZA$.W3
/** 6@wnF>'/\
* if(p<=0) p=1 6.EfM^[
* )UI T'*ow
* @param p UrH^T;#
*/ *B)>5r
publicvoid setP(int p){ &%fy
if(p <= 0) g5V9fnb!d
p = 1; ;g^QHr
this.p = p; ?.v!RdM+
} S%Pk@n`z]
6%U1%;
/** w{F8]N>0<
* 每页记录数量 cGsP0LkHC
*/ {h&*H[Z z
publicint getNum(){ yIXM}i:
return num; 9H1R0iWW
} \r324Bw>2
q}ZZqYk
/** "o<:[c9/
* if(num<1) num=1 9V.)=*0hp
*/ k#JFDw\
publicvoid setNum(int num){ S?OK@UEJ
if(num < 1) s]5wzbF O
num = 1; @K4} cP
this.num = num; J0d +q!
} ,BW^j.7
7xwS
.|
/** |ng[s6uf
* 获得总页数 x@v,qF$K
*/ u<!!%C~+=
publicint getPageNum(){ <C+:hsS=
return(count - 1) / num + 1; {8@?9Z9R{
} .Z8 x!!Q*
udp&