Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 12yX`9h>
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 >l!DWi6
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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 2a:JtJLl
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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 :WdiH)Zv
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分页支持类: wz5*?[4
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java代码: 8Vqh1<
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package com.javaeye.common.util; J9/}ZD^
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import java.util.List; l050n9#9p
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publicclass PaginationSupport { *.Ceb%W7C
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publicfinalstaticint PAGESIZE = 30; _cH 7lO[
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privateint pageSize = PAGESIZE; )~[hf,R5S
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privateList items; [O(8izv
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privateint totalCount; j]5bs*G
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privateint[] indexes = newint[0]; KZSvT{
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privateint startIndex = 0; }W k!):=y
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public PaginationSupport(List items, int -.X-02
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totalCount){ J.QFrIB{]+
setPageSize(PAGESIZE); DJf!{:b)
setTotalCount(totalCount); `V[{,!l;X
setItems(items); r.b!3CoQ
setStartIndex(0); \`M8Mu9~w
} _}-Ed,.=
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public PaginationSupport(List items, int J
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totalCount, int startIndex){ m|w-}s,
setPageSize(PAGESIZE); >HY(
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setTotalCount(totalCount); -(]s!,
setItems(items); rt[w
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setStartIndex(startIndex); %Cz&7 qf"
} na1*^S`[
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public PaginationSupport(List items, int ?
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totalCount, int pageSize, int startIndex){ N3J;_=<4
setPageSize(pageSize); |B;tv#mKD
setTotalCount(totalCount); :v!e8kM\x
setItems(items); 9I;d>%
setStartIndex(startIndex); ]hL`HP
} t$lO~~atr
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publicList getItems(){ ?@i_\<A2
return items; ]FNqNZ
} sox0:9Oqnf
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publicvoid setItems(List items){ j!:^+F/
this.items = items; &6`h%;a/&
} 58@YWvAk
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publicint getPageSize(){ =k\V~8XZ
return pageSize; fGtUr_D
} j:;[Y `2
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publicvoid setPageSize(int pageSize){ $R2iSu{kO
this.pageSize = pageSize; yIL6Sb
} z_^Vgb]
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publicint getTotalCount(){ eiV[y^?
return totalCount; eI7FbOze
} i0y^b5@MOb
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publicvoid setTotalCount(int totalCount){ M ;\iL?,
if(totalCount > 0){ qQu}4Ye>
this.totalCount = totalCount; W
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int count = totalCount / 5QjM,"`mp
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pageSize; + S^OzCGk
if(totalCount % pageSize > 0) (HW!!xM
count++; J7`fve
indexes = newint[count]; }j/($,
for(int i = 0; i < count; i++){ #MyR:V*a
indexes = pageSize * ,u1Yn}
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i; 7)`U%}R
} k e
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}else{ :QGd/JX$n`
this.totalCount = 0; 2|KgRk|!
} V kA$T8
} [!ghI%VK
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publicint[] getIndexes(){ &G)I|mv
return indexes; ?~vVSY
} 0GtL6M@pP
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publicvoid setIndexes(int[] indexes){ iz&$q]P8
this.indexes = indexes; avmuI^LLs
} S4m??B
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publicint getStartIndex(){ '
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return startIndex; 6 K+DgNK
} =r3 %jWH6
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publicvoid setStartIndex(int startIndex){ GESEj%R/b
if(totalCount <= 0) D`?=]Ysz(
this.startIndex = 0; J3F-Yl|
elseif(startIndex >= totalCount) i|]Kw9
this.startIndex = indexes !\
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[indexes.length - 1]; Nq`@ >Ml
elseif(startIndex < 0) eD4qh4|u.
this.startIndex = 0; (h}5*u%h
else{ Q M#1XbT
this.startIndex = indexes L9| 55z
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[startIndex / pageSize]; Rr'#OxF
} b) k\?'j
} 0h[pw
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publicint getNextIndex(){ |\?mX=a.y
int nextIndex = getStartIndex() + s#%$aQ|Fp
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pageSize; wxa?.
if(nextIndex >= totalCount) u3"0K['3
return getStartIndex(); ?s=O6D&
else Vq'\`$_
return nextIndex; 5r*5Co+
} eI+<^p_j2
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publicint getPreviousIndex(){ _GoV\wGKl
int previousIndex = getStartIndex() - LH=gNFgzt
#DBg8
pageSize; [Eeanl&x>
if(previousIndex < 0) ewo]-BQS
return0; i++a^f
else $pV:)N4
return previousIndex; YP^=b}
} JHxy_<p/
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} 4pvT?s>68
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抽象业务类 ^#|Sl D]
java代码: $pKlF0 .
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/** skd3E4
* Created on 2005-7-12 |WiE`&?xP
*/ e-!6m#0
package com.javaeye.common.business; z%)~s/2Rs
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import java.io.Serializable;
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import java.util.List; <>n-+Kr
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import org.hibernate.Criteria; :U6"HP+?g-
import org.hibernate.HibernateException; <EhOIN7@*D
import org.hibernate.Session; v r=va5
import org.hibernate.criterion.DetachedCriteria; ans(^Up$
import org.hibernate.criterion.Projections; \#
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import s6q6)RD"
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org.springframework.orm.hibernate3.HibernateCallback; FAkrM?0/
import {\1:2UKkr
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org.springframework.orm.hibernate3.support.HibernateDaoS .tdaj6x
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upport; i\zVP.c])*
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import com.javaeye.common.util.PaginationSupport; IP LKOT~
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public abstract class AbstractManager extends V-{3)6I$hG
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HibernateDaoSupport { Udi
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privateboolean cacheQueries = false; NmuzAZr
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privateString queryCacheRegion; @%'1Jd7-Wp
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publicvoid setCacheQueries(boolean Dhe*)
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cacheQueries){ -;:.+1
this.cacheQueries = cacheQueries; }T5
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} V&h{a8xa$
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publicvoid setQueryCacheRegion(String t] CA!i`
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queryCacheRegion){ y}F;~H~P
this.queryCacheRegion = 6MD9DqD
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queryCacheRegion; EKD?j
} /szwVA
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publicvoid save(finalObject entity){ sTxgU !_
getHibernateTemplate().save(entity); mDXG~*1
} =h@t#-Z"
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publicvoid persist(finalObject entity){ O**~ Tj
getHibernateTemplate().save(entity); *mJ\Tzc)
} kz*6%Cg*~
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publicvoid update(finalObject entity){ :O'QL,
getHibernateTemplate().update(entity); U2Tw_
} ^OOoo2
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publicvoid delete(finalObject entity){ Eq?U$eE
getHibernateTemplate().delete(entity); UQg_y3
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} *Fg)`M3g
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publicObject load(finalClass entity, i5,yrPF
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finalSerializable id){ '~9w<dSB!r
return getHibernateTemplate().load `Frr?.3&-
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(entity, id); TVM19)9
} .0rTk$B
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publicObject get(finalClass entity, A"O\u=!
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finalSerializable id){ mKqXB\<
return getHibernateTemplate().get ^;9<7h[l
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(entity, id); 6)PnzeYW
} vqAEF^HYry
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publicList findAll(finalClass entity){ rb*0YCi
return getHibernateTemplate().find("from wmA TV/
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" + entity.getName()); 8(ot<3(D
} 6M
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publicList findByNamedQuery(finalString `TYC]9
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namedQuery){ ?iZM.$![
return getHibernateTemplate l;rA}?,.^
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().findByNamedQuery(namedQuery); !' 0PM[
} ckb(+*+l
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publicList findByNamedQuery(finalString query, &Hyy .a
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finalObject parameter){ WH"'Ju5}
return getHibernateTemplate {<$tEj:
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().findByNamedQuery(query, parameter); 01&@8z'E
} 2acTw#
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publicList findByNamedQuery(finalString query, k 1a?yH)=
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finalObject[] parameters){ 2+/r~LwbK
return getHibernateTemplate dW22v!
>& 4) :
().findByNamedQuery(query, parameters); Eyz.^)r
} )4h|7^6ji
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publicList find(finalString query){ !x:{"
return getHibernateTemplate().find U[2;Fkapi
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(query); %#o@ c
} <d"nz:e
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publicList find(finalString query, finalObject vcCNxIzEG
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parameter){ Y<jX[ET!
return getHibernateTemplate().find =''WA:,=h
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(query, parameter); @lX%Fix9
} #jzF6j%G
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public PaginationSupport findPageByCriteria -L4G)%L\
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(final DetachedCriteria detachedCriteria){ ~]#-S20
return findPageByCriteria <Y6zJ#BD
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ]R>NmjAI
} 5]up%.
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public PaginationSupport findPageByCriteria z]SEPYq:
:?j=MV
(final DetachedCriteria detachedCriteria, finalint :nR80]
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startIndex){ b`$qKO
return findPageByCriteria B'Jf&v
{* :^K\-
(detachedCriteria, PaginationSupport.PAGESIZE, SSCs96
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startIndex); 2 S~( P
} 2@lGY_O!m
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public PaginationSupport findPageByCriteria by0K:*C
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(final DetachedCriteria detachedCriteria, finalint `"}).{N]C
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pageSize, +ue1+#
finalint startIndex){ ',xUU{5?
return(PaginationSupport) .>#O'Z&q9
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getHibernateTemplate().execute(new HibernateCallback(){ 4`)r1D!U
publicObject doInHibernate c-5AI{%bl6
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(Session session)throws HibernateException { :aBxyS*}G
Criteria criteria = ,}]v7DD
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detachedCriteria.getExecutableCriteria(session); k7Qs#L
int totalCount = *l4[`7|
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((Integer) criteria.setProjection(Projections.rowCount #R:&Irh
m<)`@6a/
()).uniqueResult()).intValue(); cfilH"EK
criteria.setProjection :hs~;vn)
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(null); 7M4J{}9
List items = 9PA<g3z
akNqSZwj
criteria.setFirstResult(startIndex).setMaxResults r180vbN$
hSw=Oq82
(pageSize).list(); Ha|}Oj
PaginationSupport ps = AEaN7[PQx|
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new PaginationSupport(items, totalCount, pageSize, ?T_MP"
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startIndex); De^:9<{jc
return ps; [520!JhZY
} \eNB L[
}, true); M;Pry3J
} lq "X_M$
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public List findAllByCriteria(final +B1&bOb
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DetachedCriteria detachedCriteria){ %Z <{CV
return(List) getHibernateTemplate Q&vdBO/
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().execute(new HibernateCallback(){ ha$1vi}b
publicObject doInHibernate 6 5dMv*{
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(Session session)throws HibernateException { 2b"DkJj'
Criteria criteria = Cs[d:T
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detachedCriteria.getExecutableCriteria(session); &K60n6q{aQ
return criteria.list(); _qf39fM;\
} /q\e&&e
}, true); ~a[/l
} ,>rvl P
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public int getCountByCriteria(final X*@ tp,t
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DetachedCriteria detachedCriteria){ Pb>/b\&JS
Integer count = (Integer) 64mEZ_kG,
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getHibernateTemplate().execute(new HibernateCallback(){ 6QY;t:/<
publicObject doInHibernate P9'`
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(Session session)throws HibernateException { ;10YG6:
Criteria criteria = m!Z<\2OP
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detachedCriteria.getExecutableCriteria(session); 4>0q0}J=5
return 0=3)`v{S@
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criteria.setProjection(Projections.rowCount p__wBUB
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()).uniqueResult(); c?HUW
} ^@AyC"K
}, true); -)oUb=Lk{
return count.intValue(); [ ,Go*r
} ]/1\.<uJId
} ; $80}TY '
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用户在web层构造查询条件detachedCriteria,和可选的 Y /_CPY
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Na/Y1RW
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PaginationSupport的实例ps。 ft(o-f7,
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ps.getItems()得到已分页好的结果集 E|f[#+:+
ps.getIndexes()得到分页索引的数组 Ha-]U:Vcx
ps.getTotalCount()得到总结果数 U[f00m5{HV
ps.getStartIndex()当前分页索引 ?$109wZ:9
ps.getNextIndex()下一页索引 I*
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ps.getPreviousIndex()上一页索引 rMx Iujx
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 :LNE?@
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 50N4J
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一下代码重构了。 :Fb>=e
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我把原本我的做法也提供出来供大家讨论吧: U*$P"sS`
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首先,为了实现分页查询,我封装了一个Page类: Om0$6O
java代码: zW%Em81Wd
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/*Created on 2005-4-14*/ Re8x!e'>
package org.flyware.util.page; !Rl|o^Vw>{
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/** hHE~/U
* @author Joa h.>SVQzU
* E:pk'G0bZ
*/
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publicclass Page { ]WDmx$"&e
^b+>r
/** imply if the page has previous page */ RtMI[
privateboolean hasPrePage; v<!S_7h
29RP$$gR
/** imply if the page has next page */ DQXUh#t\(]
privateboolean hasNextPage; mgjJNzclL
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/** the number of every page */ MJ)lZ!KZ
privateint everyPage; #4'wF4DR@
pd'0|
/** the total page number */ w'H'o!*/
privateint totalPage; l:V
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/** the number of current page */ >s{I@#9
privateint currentPage; }%jF!d
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/** the begin index of the records by the current Zok{ndO@|f
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query */ nTqU~'d'
privateint beginIndex; CjQO5
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/** The default constructor */ 9b+jT{Tg
public Page(){ `-L?x2)U
dM-cQo:
} 1(?4*v@B
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/** construct the page by everyPage SN{+ P k
* @param everyPage iNA3Y
* */ +NPL.b|
public Page(int everyPage){ %F>~2g?$
this.everyPage = everyPage; !2LX+*;
} K&|h%4O
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/** The whole constructor */ ^Pn|Q'{/p
public Page(boolean hasPrePage, boolean hasNextPage, O^@8Drgc
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t/iI!}
int everyPage, int totalPage, b&z#ZY
int currentPage, int beginIndex){ lYx_8x2
this.hasPrePage = hasPrePage; Zo3!Hs ZA
this.hasNextPage = hasNextPage; uYUFxm
this.everyPage = everyPage; XQ]K,# i
this.totalPage = totalPage; Yr9'2.%Q
this.currentPage = currentPage; y*i&p4Y*
this.beginIndex = beginIndex; 2zBk#c+
} ~R!1{8HP
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/** Ia&*JYM[
* @return n$/|r
* Returns the beginIndex. F(G..XJQ
*/ 0WUBj:@g
publicint getBeginIndex(){ k)p`x"To
return beginIndex; B@,r8)D
} .q@?sdGD
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/** =A"Abmx|
* @param beginIndex \H] |5fp*
* The beginIndex to set. uAO!fE}CJ
*/ >f]/VaMH{
publicvoid setBeginIndex(int beginIndex){ KUI{Z I
this.beginIndex = beginIndex; cbzA`b'Mg
} N"S`9B1eD(
pi"H?EHk
/** ,-pE/3|(
* @return uBm"Xkxe|w
* Returns the currentPage. ,-c,3/tyA
*/ 66v,/#K
publicint getCurrentPage(){ 7d: ]o>
return currentPage; /G||_Hc
} )pWgt5:7~
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/** 1V%tev9a
* @param currentPage jRK}H*uem
* The currentPage to set. Y <6|z3
*/ KYFKH+d>m
publicvoid setCurrentPage(int currentPage){ V"/.An|
this.currentPage = currentPage; xVx s~p1
} -c`xeuzK'
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/** 37U8<
* @return ]>n{~4a
* Returns the everyPage. (t4i&7-
*/ Oyl~j#h
publicint getEveryPage(){ B"^j>SF
return everyPage; ^h[6{F~J
} 1WUSp;JMl
@.t +
/** BlVHP8/b
* @param everyPage V%,,GmiU]
* The everyPage to set. /Ew()>Y
*/ |L<JOQ
publicvoid setEveryPage(int everyPage){ RNT9M:w
this.everyPage = everyPage; B>2=IZ
} ^{Y, `F
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/** +b|F_
* @return k6tCfq;
* Returns the hasNextPage. =M\yh,s!
*/ bxXpw&
publicboolean getHasNextPage(){ GkAd"<B
return hasNextPage; *6s_7{;
} {*_Ln
Aiq Kf=
/** LO`0^r
* @param hasNextPage 46?z*~*G
* The hasNextPage to set. W{,fpm
*/ Hv/C40uM-
publicvoid setHasNextPage(boolean hasNextPage){ 6{2y$'m8
this.hasNextPage = hasNextPage; x ytrd.
} A4j,]hOD
odP<S.
/** o@Ye_aM~?Y
* @return 1[egCC\Mo_
* Returns the hasPrePage. mv9D{_,pD
*/ RD`|Z~:q:K
publicboolean getHasPrePage(){ +t7HlAXB#
return hasPrePage; IFLphm5
} ql?w6qFs]
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/** )~'UJPK
* @param hasPrePage mR0`wrt
* The hasPrePage to set. (j8*F Bq
*/ @-q,%)?0}=
publicvoid setHasPrePage(boolean hasPrePage){ '(]Wtx%9"
this.hasPrePage = hasPrePage; Wv4$Lgr
} (:iMs)
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/** 2[lP ,;!
* @return Returns the totalPage. [v1$Lp
* z~H1f$}
*/ 5hE#y]pfN
publicint getTotalPage(){ ~kc#"^sJ
return totalPage; Y.m1d ?H 1
} `_J&*Kk5
htB2?%S=T
/** {|9knP
* @param totalPage A}(xH`A
* The totalPage to set. M+t)#O4
*/ Zg+.`>z
publicvoid setTotalPage(int totalPage){ igu1s}F
this.totalPage = totalPage; {4+/0\
} :!i=g+e]
cS.@02~f"
} 5<Kt"5Z%7
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 uQdeKp4(
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个PageUtil,负责对Page对象进行构造: &v:zS$m>
java代码: !
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/*Created on 2005-4-14*/ =eA|gt
package org.flyware.util.page; yzEyOz@Q
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import org.apache.commons.logging.Log; F=F84_+K
import org.apache.commons.logging.LogFactory; ww|fqx?
?>7\L'n=5I
/** 0A}XhX
* @author Joa veDv14
* zlLZ8b+
*/ 3]S*p ErY
publicclass PageUtil { :$I"n\
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privatestaticfinal Log logger = LogFactory.getLog F2YBkwI
uGAQt9$>_
(PageUtil.class); 1c,#`\Iikd
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/** MJX
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* Use the origin page to create a new page % )V=)l.j
* @param page 7sVM[lr<
* @param totalRecords O+!4KNN.-
* @return 8jCho
*/ 9DBX.|
publicstatic Page createPage(Page page, int ij:xr% FJ
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totalRecords){ ]MCH]/
return createPage(page.getEveryPage(), U<Oc&S{]*
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page.getCurrentPage(), totalRecords); t %u0=V
} L#`X
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/** Qi\]='C
* the basic page utils not including exception 6$#,$a O
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handler 5kqI
* @param everyPage G5hRx@vfrL
* @param currentPage `K VSYC
* @param totalRecords 39^+;Mev
* @return page )EMlGM'2q
*/ $`OyGeq"T
publicstatic Page createPage(int everyPage, int d/GSG%zB
tnpEfi-
currentPage, int totalRecords){ IV~)BW leT
everyPage = getEveryPage(everyPage); C32*RNG?U
currentPage = getCurrentPage(currentPage); f)vnm*&-
int beginIndex = getBeginIndex(everyPage, ~v&Q\>'
B\D)21Ik}%
currentPage); T Tbe{nb
int totalPage = getTotalPage(everyPage, (tO4UI5!
9@qkj
4w
totalRecords); [cDkmRV
boolean hasNextPage = hasNextPage(currentPage, R?{_Q<17
tF[)Y#
totalPage); 86LE
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boolean hasPrePage = hasPrePage(currentPage); 5XT^K)'
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returnnew Page(hasPrePage, hasNextPage, ~F@p}u8TV
everyPage, totalPage, bD)"Jy
currentPage, ]U@~vA#''
jhRr!
beginIndex); KrP?*yk
} "T[BSj?E
b1^wK"#
privatestaticint getEveryPage(int everyPage){ L=54uCv
Q
return everyPage == 0 ? 10 : everyPage; u ^#UsOt+
} %i7U+v(d
#n&/v'!\
privatestaticint getCurrentPage(int currentPage){ y?cN
return currentPage == 0 ? 1 : currentPage; 0.m-}
} f0@*>
I>rTqOK
privatestaticint getBeginIndex(int everyPage, int ,g'>Ib%
xi"ff.
currentPage){ {zd[8TJ~xa
return(currentPage - 1) * everyPage; Sg%s\p]N_#
} X<_HQ
Qu<6X@+5
privatestaticint getTotalPage(int everyPage, int +hKU]DP2;
%J'/ cmR&
totalRecords){ ].Bx"L!B
int totalPage = 0; f5M;q;
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if(totalRecords % everyPage == 0) @gqZiFM)
totalPage = totalRecords / everyPage; E"[p_ALdC
else L!Tvz(_7f6
totalPage = totalRecords / everyPage + 1 ; aZo}Ix:/
{o^tSEN!-
return totalPage; Qm7];,
} ;t9!<L
3O4,LXdA
privatestaticboolean hasPrePage(int currentPage){ PI$i_3N
return currentPage == 1 ? false : true; &2%|?f|
} !\VEUF,K?
)sQ/$gJ
privatestaticboolean hasNextPage(int currentPage, J:'_S `J
0datzEns`
int totalPage){ G*_]Lz(N
return currentPage == totalPage || totalPage == r"K!]Vw
lq.]@zlSO
0 ? false : true; t%e<]2-8
} `z q+Xl
|Wa.W0A
<7)sS<I
} S W6oaa81
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/Q)I5sL@E
9D`K#3}
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Ad,n+%"e
0=U|7%dOL
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 mA.,.<xE@
DC/Czkv9
做法如下: wC%qS y'
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 y'b*Dk{
6`6 / 2C$%
的信息,和一个结果集List: %rhZH^2
java代码: iF
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}=\?]9`
CV=qcD
/*Created on 2005-6-13*/ f|_\GVW
package com.adt.bo; <@GO]vY
2?6]Xbs{
import java.util.List; xR
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import org.flyware.util.page.Page; g yV>k=B
'wYIJK~1
/** &uc`w{,Zs
* @author Joa a6;[Z
*/ !&b|
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publicclass Result { 6jBi?>[I
=NY55t.
private Page page; djnES,^%9
R{Zd ]HT
private List content; #Ff8_xhP 2
}wp/,\_
>
/** }ssja,;
* The default constructor }6.@
*/ Ua:@,};
public Result(){ }.'rhR+
super(); 2ry@<88
} 'oY#a9~Z{
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/** {PxFG<^U
* The constructor using fields J;^ PM:6
* %GY'pQz
* @param page })70S8k
* @param content [[^95:
*/ :] U\{;q2
public Result(Page page, List content){ ,YvOk|@R
this.page = page; K, !
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this.content = content; XKws_
} &)+H''JY
b+:J?MR;}
/** h/{1(c}
* @return Returns the content. >P@VD"U
*/ T^`; wD
publicList getContent(){ li\=mH,Wr
return content; JrY*K|YdW
} 6i+,/vr
OqciZ@#5n
/** x>##qYT
* @return Returns the page. j-R*!i
*/ y2jw3R
public Page getPage(){ 3TCRCz
return page; Ic_NQ<8
} >l AtfN='
*-5N0K<kQ
/** 4c(Em+4
* @param content I-g/)2
* The content to set. $F#
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*/ 7mdd}L^h
Z
public void setContent(List content){ K.mxF,H
this.content = content; yj_> G
} 6*>Lud
@j}%{Km]Y
/** m#8PX$_
* @param page ;9h;oB@
* The page to set. n6WKk+
*/ }]mxKz
publicvoid setPage(Page page){ n }A!aC
this.page = page; Mhti
} :zKMw=
} 4L8hn4F
R^/SBrWve
0stc$~~v
HrsG^x
#L+:MA7H
2. 编写业务逻辑接口,并实现它(UserManager, 7LrmI~P
rq8 d}wj
UserManagerImpl) lcm[l
java代码: z
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1]~w?)..'
+Z|3[#W
/*Created on 2005-7-15*/ u>:(MARsR
package com.adt.service; /o m++DxV
RhHm[aN
import net.sf.hibernate.HibernateException; U3V5Jor#
1s.2z[B~
import org.flyware.util.page.Page; zX&SnT1~
?BfE*I$\h
import com.adt.bo.Result; (VjU ,'h
`2@.%s1o=
/** R'tKJ_VI
* @author Joa rniM[7K
*/ [DM0'4
publicinterface UserManager { ^
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z.SC^/\o|
public Result listUser(Page page)throws bqAW
[#q>Aq$11
HibernateException; W~ET/h
(n*:LS=0
} p8!T)
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A'KH_])
6j<!W+~G
qtZ?
kJ
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java代码: {k)gDJU
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qXdari
/*Created on 2005-7-15*/
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package com.adt.service.impl; m<-ShRr*b
I}
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import java.util.List; /qX?ca1_4^
'V]&X.=zC
import net.sf.hibernate.HibernateException; "G K9Y
?FAI@4
import org.flyware.util.page.Page; RTm/-6[N
import org.flyware.util.page.PageUtil; 9dhEQ=K{3
9VnBNuT
import com.adt.bo.Result; IQ
I8v
import com.adt.dao.UserDAO; rKrHd
import com.adt.exception.ObjectNotFoundException; f
5v&4
import com.adt.service.UserManager; k9;^|Cm
k
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/** aZWj52
* @author Joa cQK-Euum
*/ _VKI@
publicclass UserManagerImpl implements UserManager { CP~ZIIip"
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private UserDAO userDAO; cg MF?;V
sF{aG6u
/** X@\W*
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* @param userDAO The userDAO to set. DpT9"?g7
*/ g|>LT_
publicvoid setUserDAO(UserDAO userDAO){ sCFxn
this.userDAO = userDAO; i3,IEN
} (aa2uctTn
{rUg,y{v
/* (non-Javadoc) eluN~T:W
* @see com.adt.service.UserManager#listUser @&ZQDi
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(org.flyware.util.page.Page) DW. w=L|5R
*/ RSp wU;o6z
public Result listUser(Page page)throws .$18%jH#
$8=|<vt
HibernateException, ObjectNotFoundException { } a9Ah:.7/
int totalRecords = userDAO.getUserCount(); R c+olJ^5
if(totalRecords == 0) T-en|.
throw new ObjectNotFoundException ^viabkf C
_p-e)J$7
("userNotExist"); &J>e;X
page = PageUtil.createPage(page, totalRecords); N*o{BboK;
List users = userDAO.getUserByPage(page); UZyg_G6
returnnew Result(page, users); @AEH?gOX
} LjI`$r.B
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} .:$(o&
8W\yM;'
_}R[mr/
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x}+zhRJ
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fST.p|b7
p0Jr{hM
询,接下来编写UserDAO的代码: . <"XE7
3. UserDAO 和 UserDAOImpl: =nhY;pY3u
java代码: [7Lr"
dHc\M|HCC
+OE!Uqnt
/*Created on 2005-7-15*/ 94"+l@K
package com.adt.dao; =,6H2ew
Y![Q1D!
import java.util.List; y{%0[x*N<m
s#9q3JV0
import org.flyware.util.page.Page; 4S<M9A}
v675C# l(
import net.sf.hibernate.HibernateException; ?QOU9"@+B
`q?3ux
/** b@Ej$t&
* @author Joa qjB:6Jq4q
*/ #-0e0
publicinterface UserDAO extends BaseDAO { 3p%e_?
pU$k{^'UK
publicList getUserByName(String name)throws sQJ\{'g
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Uj<[O
HibernateException; YOl$sgg}
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publicint getUserCount()throws HibernateException; gP2zDI
tT}b_r7h(1
publicList getUserByPage(Page page)throws jn<?,UABD
uX_H;,n
HibernateException; o(*\MTt?
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} x4MmBVqp
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v e&d"8+]
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/8x';hQ
java代码: azP H~'E'
{^N,=m\
u8Ys2KLpL
/*Created on 2005-7-15*/ 2n<Mu Q]
package com.adt.dao.impl; Qs&;MW4q
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import java.util.List; >y3FU1w5d
>q"dLZ
import org.flyware.util.page.Page; `i.BB jx`
,mHME~
import net.sf.hibernate.HibernateException; Y^fw37b
import net.sf.hibernate.Query; \ruQx)5M
Aa
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import com.adt.dao.UserDAO; (95|DCL
#T=iS(i
/** Tagf7tw4
* @author Joa 'C]w3Rh'
*/ xl&@g)Jj
public class UserDAOImpl extends BaseDAOHibernateImpl &<A,\M
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implements UserDAO { -D`1z?zHra
qSY\a\.<
/* (non-Javadoc) &
l>nzJ5?
* @see com.adt.dao.UserDAO#getUserByName {wqT$( (<
bb6x} jR
(java.lang.String) (GJtTp~2C4
*/ _Mw3>GNl
publicList getUserByName(String name)throws D2$9$xeR
UB$}`39@
HibernateException { j-<-!jTd
String querySentence = "FROM user in class O_FB^BB
Nk'<*;e
com.adt.po.User WHERE user.name=:name"; IMf|/a9-
Query query = getSession().createQuery 5vx 4F f
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(querySentence); 6,>$Jzs)5E
query.setParameter("name", name); K*~{M+lU7
return query.list(); 3=O [Q :8
} ;_<~9;
~KK}
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/* (non-Javadoc) sxNf"C=-.
* @see com.adt.dao.UserDAO#getUserCount() [D"6&
*/ z|#*c5Y9w
publicint getUserCount()throws HibernateException { ?P
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int count = 0; Y~"tL(WfJl
String querySentence = "SELECT count(*) FROM gIB3DuUo
Od!)MQ*,
user in class com.adt.po.User"; IWv 9!lW
Query query = getSession().createQuery pN9 !
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(querySentence); irt9%w4"
count = ((Integer)query.iterate().next & NYaKu,}
JW>k8QjyN
()).intValue(); CIW4E
return count; 6.@.k
} m{IlRf'
zMSwU]4I!
/* (non-Javadoc) R{g=
N%O
* @see com.adt.dao.UserDAO#getUserByPage ;K<VT\
wm5&5F4:
(org.flyware.util.page.Page) "n%j2"TYJj
*/ 25X|N=}
publicList getUserByPage(Page page)throws )D8op;Fn
+~8Lc'0aA
HibernateException { 8zK#./0\
String querySentence = "FROM user in class 'uu*DgEr
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com.adt.po.User"; "~4V(
Query query = getSession().createQuery 5rsz2;#p
ufXWK3~\
(querySentence); "Bd-h|J
query.setFirstResult(page.getBeginIndex()) ,rB(WKU
.setMaxResults(page.getEveryPage()); /YJo"\7
return query.list(); 01.q9AGy
} GfONm6A
L3eF BF/
} ,DFN:uf=l
J!C \R5\
@)pC3Vi^
9qap#A
wB)y@w4k
至此,一个完整的分页程序完成。前台的只需要调用 ;[y( 14g
gj^)T_E_
userManager.listUser(page)即可得到一个Page对象和结果集对象 F_@B ` ,
e{x>u(
的综合体,而传入的参数page对象则可以由前台传入,如果用 b|i4me@
~XR('}5D
webwork,甚至可以直接在配置文件中指定。 S{^x]h|?
bxE~tsM"@Y
下面给出一个webwork调用示例: aL(G0@(
java代码: j4XVk@'OX
ka_m
Q<{9
#9GfMxH
/*Created on 2005-6-17*/ ?`RlYu
package com.adt.action.user; /pF8S!,z
d+DO}=]
import java.util.List; vu(
5s
A@?0(
import org.apache.commons.logging.Log; @b(@`yz.a
import org.apache.commons.logging.LogFactory; 6,q0F*q
import org.flyware.util.page.Page; \&F4Wl>`
+$C9@CZM9
import com.adt.bo.Result; %R GZu\p
import com.adt.service.UserService; o*K7(yUL4
import com.opensymphony.xwork.Action; 0>Y3xNb
|k}<Zz1UM
/** ?d Jd7+A
* @author Joa %bw+>:Tr
*/ [{Wo:c9Qq1
publicclass ListUser implementsAction{ 6FDj :~
`:&RB4Z
privatestaticfinal Log logger = LogFactory.getLog N82 6xvA
lf"w/pb'
(ListUser.class); EjfQF C
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private UserService userService; b
ri[&=
i*$+>3Q-
private Page page; &4OOW;,?<
ZX/FIxpy
privateList users; HzM\<YD
pCt2-aam
/* i ;B^I8
* (non-Javadoc) 5WI
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* d>[i*u,]/
* @see com.opensymphony.xwork.Action#execute() b36{vcs~
*/ 2)IM<rf'^
publicString execute()throwsException{ 1gK|n
Result result = userService.listUser(page); )M;~j
page = result.getPage(); 0er|QC
users = result.getContent(); p@pb[Bx~[
return SUCCESS; +pYgh8w@
} w10~IP
|47t+[b
/** ^p(aZj3k
* @return Returns the page. QtfL'su:
*/ [pU(z'caS
public Page getPage(){ -W!M:8
return page;
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} X>$Wf3
$6m@gW]N
/** =mLp g4
* @return Returns the users. r(Sh
*/ eFsl
publicList getUsers(){ gq?O}gVD
return users; )VQ[}iT
} UXji$|ET6
DOu^
/** igL5nE=n
* @param page (-yif&
* The page to set. "]jN'N(.
*/ 4Pr^>m
publicvoid setPage(Page page){ #_^p~:
this.page = page; wfO-bzdw
} o|>=<l
="]lN
/** |8E~C~d
* @param users r.)n>
* The users to set. yLf9cS6=
*/
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publicvoid setUsers(List users){ ItLR|LO9
this.users = users; l!}gWd,H
} AyQ5jkIE^{
vRtERFL
/** yW?-Z[
* @param userService M gP|'H3\
* The userService to set. B^9C}QB
*/ Sm[#L`eqW
publicvoid setUserService(UserService userService){ hqeknTGsIn
this.userService = userService; +6>2= ,?Z
} z~f;}`0
} xJw"
8V<
3B;Gm<fJ9N
l\0PwD
[;hkT
rXmrT%7k
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, 0#GnmH
b)a5LFt|
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 ]2L11"erP
BHp>(7,
么只需要: ] K&ca
java代码: H.M:
cD:
xY)eU;*
!.%*Tp#k#
<?xml version="1.0"?> K"[jrvZ=
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork =W2.Nc
#IGcQY
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ommW
c1kV}-v
1.0.dtd"> (XR}U6^v]
1/\Xngd
<xwork> 2FdwX,O.
Qxy~%;X
<package name="user" extends="webwork- DEu0Z
Vel(+HS
interceptors"> ?VxQ&^|
GR(m+%Vw!
<!-- The default interceptor stack name %{'[S0 @Z
tYMr
--> 8~qpOQX^V
<default-interceptor-ref
3<.DiY
6Jy%4]wK
name="myDefaultWebStack"/> ZuWhgnp
e+#Oj
<action name="listUser" GZ<@#~1%\
p-"wY?q
class="com.adt.action.user.ListUser"> "r;cH5 3
<param E_30)"]
A##Q>|>)
name="page.everyPage">10</param> Dd0yQgCu
<result b"@-9ke5I
nzxHd7NIZ
name="success">/user/user_list.jsp</result> !p ~.Y+
</action> M`#g>~bI#R
kLs{B
</package> %iPIgma
sMAH;'`!Eu
</xwork> &Odrq#o?R
xP9R
d/xa|
IecD41%
8WLh7[
y+wy<[u
i`6utOq
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 S\ZCZ0
RKMF?:
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。 41B.ZE+*qd
H[g i`{c
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 EQ"_kJ>81Y
)2Q0NbDn
#WUN=u
8>|4iT
8DD1wK\U~
我写的一个用于分页的类,用了泛型了,hoho #6y fIvap
{?w*n_T.
java代码: Ac*)z#H
Grw[h
2fayQY
xD
package com.intokr.util; %26HB
w=JF
/ E!6]b/
import java.util.List; 7"eIZ
+yr~UP_
}
/** D}{]5R
* 用于分页的类<br> bA6^RIf?
* 可以用于传递查询的结果也可以用于传送查询的参数<br> x`p908S^
* -NzOX"V]3
* @version 0.01 ^755LW
* @author cheng @VND}{j
*/ 1*#hIuoj'
public class Paginator<E> { &f A1kG%
privateint count = 0; // 总记录数 ^eV K.
privateint p = 1; // 页编号 $^e_4]k
privateint num = 20; // 每页的记录数 B'B0 e`
privateList<E> results = null; // 结果 ~y 2joStx
vPZ0?r_5W
/** 7k#>$sY+
* 结果总数 ;$*tn"- ?~
*/ 0|hOoO]?q&
publicint getCount(){ v-F|#4Q=ut
return count; D!)h92CIDm
} P$O@G$n
Efd@\m:~>
publicvoid setCount(int count){ I?q-
:9:
this.count = count; E-9>lb
} q?w%%.9]X
Jn&u