Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 OJ}aN>k
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 `e+eL*rZ~
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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 Q8bn|#`
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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 jHc/ EZB
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。 N{fYO4O
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分页支持类: aGmbB7[BZ
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java代码: GC~N$!*
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package com.javaeye.common.util; ^Kh>La:>O
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import java.util.List; )"y]_}
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publicclass PaginationSupport { p9iCrqi
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publicfinalstaticint PAGESIZE = 30; m{0u+obi&w
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privateint pageSize = PAGESIZE; \EEU G^T
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privateList items; |n.ydyu`
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privateint totalCount; n 0ls a@l
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privateint[] indexes = newint[0]; +PkN~m`
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privateint startIndex = 0; Q$DF3[NC
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public PaginationSupport(List items, int ]ch=D
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totalCount){ (ZuV5|N
setPageSize(PAGESIZE); V3}$vKQ
setTotalCount(totalCount); +v'n[xa1v
setItems(items); u+uu?.bM
setStartIndex(0); TVFxEV7Fx
} &M^FA=J\
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public PaginationSupport(List items, int >@U
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totalCount, int startIndex){ _i{4 4zE
setPageSize(PAGESIZE); t9
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setTotalCount(totalCount); o M#S.f?
setItems(items); s
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setStartIndex(startIndex); prg8Iq'w
} z?8Sie
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public PaginationSupport(List items, int b`sph%&
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totalCount, int pageSize, int startIndex){ -d6*M*{|
setPageSize(pageSize); =Z(#j5TGvH
setTotalCount(totalCount); @3b|jJyf
setItems(items); 7'xds
setStartIndex(startIndex); #`H^8/!e
} TID0x/j"K5
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publicList getItems(){ l?%U*~*
return items; 0Ti>PR5M
} %U)M?UNjw
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publicvoid setItems(List items){ (_lc< Bj
this.items = items; 4hv'OEl
} QYL
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publicint getPageSize(){ VgNt
return pageSize; aJ Du_
} r8~U@$BBK
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publicvoid setPageSize(int pageSize){ P!";$]+
this.pageSize = pageSize; O({-lI
} *7I=vro
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publicint getTotalCount(){ U)p P^:|
return totalCount; o;JBe"1
} `v)-v<
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publicvoid setTotalCount(int totalCount){ S-h1p`
if(totalCount > 0){ .j4IW3)
this.totalCount = totalCount; jL)aU> kN
int count = totalCount / }r/L 9
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pageSize; OX4+1@$tk
if(totalCount % pageSize > 0) N3H!ptn37
count++; ls6ywLP{
indexes = newint[count]; R#bg{|
for(int i = 0; i < count; i++){ w|PZSOJ
indexes = pageSize * H2RNekck
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} TR@$$RrU
}else{ ,Ql3RO,
this.totalCount = 0; SJ7>*Sa(u$
} cuquA ~
} ^B?koU l^
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publicint[] getIndexes(){ Z[`J'}?|
return indexes; YKl!M/
} 4DfTVO"h
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publicvoid setIndexes(int[] indexes){ OG 5n9sx
this.indexes = indexes; S,S_BB<Y[b
} i`8!Vm
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publicint getStartIndex(){ ZLKS4
return startIndex; `Xmpm4 ]
} B?Y%y@.
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publicvoid setStartIndex(int startIndex){ 7X}_yMxc
if(totalCount <= 0) iJrscy-
this.startIndex = 0; T*h+"TmE
elseif(startIndex >= totalCount) NnHM$hEI"U
this.startIndex = indexes E4y"$U%.
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[indexes.length - 1]; =AcbX_[
elseif(startIndex < 0) zLXtj-
this.startIndex = 0; x5`q)!<&
else{ Bdbw!zRR$
this.startIndex = indexes 8@+YcN;->
<!OP b(g2
[startIndex / pageSize]; oS,<2Z
} ~Nc]`95
} ;- ]f4O8
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publicint getNextIndex(){ 5K6_#g4"
int nextIndex = getStartIndex() + &*)tqQeQf
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pageSize; 6o1.?t?
if(nextIndex >= totalCount) *.nqQhW
return getStartIndex(); w@%W{aUC
else Z p__
return nextIndex; ]B,S <*h
} MzG(+B
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publicint getPreviousIndex(){ ]-PF? 8
int previousIndex = getStartIndex() - <RhKlCP
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pageSize; HWefuj
if(previousIndex < 0) Le3S;SY&
return0; !w)Mm P Xb
else m1[QD26
return previousIndex; ;D^)^~7dh
} %ri4nKGS
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} `jZX(H
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抽象业务类 BO9Z"|"
java代码: j{;3+LCo*
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/** ?D\%ZXo
* Created on 2005-7-12 v;RQVH;,
*/ 6/-!oo
package com.javaeye.common.business; AQiP2`?
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import java.io.Serializable; G1nW{vce
import java.util.List; 7K;dVB
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import org.hibernate.Criteria; cUm9s>^)/
import org.hibernate.HibernateException; U1"t|KW8
import org.hibernate.Session; b?bYPN+
import org.hibernate.criterion.DetachedCriteria; Gz6GU.IyQy
import org.hibernate.criterion.Projections; .y0](
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import {&<}*4D
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org.springframework.orm.hibernate3.HibernateCallback; N{`l?t0I
import Fd\XDc[g
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org.springframework.orm.hibernate3.support.HibernateDaoS - dOT/%Ux
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upport; __V]HcP;
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import com.javaeye.common.util.PaginationSupport; jF3!}*7,
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public abstract class AbstractManager extends dq8 /^1P
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HibernateDaoSupport { op|mRJBq;
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privateboolean cacheQueries = false; V-cuG.
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privateString queryCacheRegion; OhW=F2OIV
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publicvoid setCacheQueries(boolean avpw+M6+
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cacheQueries){ jzj{{D[^
this.cacheQueries = cacheQueries; psZeu*/r
} 6|KX8\,A@
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publicvoid setQueryCacheRegion(String @*DIB+K
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queryCacheRegion){ pq[mM!;#v
this.queryCacheRegion = UC1!J
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queryCacheRegion; yo*iv+l
} Z0=m:h
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publicvoid save(finalObject entity){ B
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getHibernateTemplate().save(entity); aVP|:OAj
} '!-?
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publicvoid persist(finalObject entity){ )zXyV]xe
getHibernateTemplate().save(entity); A&P1M6Of
} <!9fJFE
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publicvoid update(finalObject entity){ Z% ;4Ed
getHibernateTemplate().update(entity); Uxemlp%%*
} ]|N4 #4
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publicvoid delete(finalObject entity){ v\Y}(fD
getHibernateTemplate().delete(entity); ~9?U_ahfVt
} nr>{ uTa
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publicObject load(finalClass entity, @E}X-r.^f
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finalSerializable id){ =YGP%}_.p{
return getHibernateTemplate().load mY`]33??v
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(entity, id); %%~}Lw
} q{GSsDo-:V
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publicObject get(finalClass entity, z9 w&uZzi
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finalSerializable id){ 2Nn1-wdhb
return getHibernateTemplate().get W3/ 7BW`
^ L^F=q x
(entity, id); tQ~<i %;
} 90T%T2K
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publicList findAll(finalClass entity){ 5}eQaW48
return getHibernateTemplate().find("from ,<3uc
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" + entity.getName()); CofH}-
} g(<T u^F
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publicList findByNamedQuery(finalString rQEi/
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namedQuery){ A/"}Y1#qX\
return getHibernateTemplate @ EmGexLPM
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().findByNamedQuery(namedQuery); Ud#X@xK<h
} 8PBU~mr
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publicList findByNamedQuery(finalString query, 5r4gmy>
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finalObject parameter){ w(/DTQc~d
return getHibernateTemplate 2vc\=
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().findByNamedQuery(query, parameter); |mxNUo-
} $J"%I$%X=
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publicList findByNamedQuery(finalString query, st?gA"5w
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finalObject[] parameters){ >?5xDbRj
return getHibernateTemplate CE#\Roi x)
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().findByNamedQuery(query, parameters); u 1ZJHry
} [?chK^8
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publicList find(finalString query){ +z-[s6q2m
return getHibernateTemplate().find #JA}LA"l
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(query); ZXsYn
} '{[!j6wt\
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publicList find(finalString query, finalObject 3J%V%}mD
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parameter){ vv+D*e&<
return getHibernateTemplate().find 5YiZ-CQ>
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(query, parameter); b5j*xZv
} &<au/^F
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public PaginationSupport findPageByCriteria eZg$AOpU
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(final DetachedCriteria detachedCriteria){ naz:A
return findPageByCriteria uBmxh%]C~
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); (ZV;$N-t
} kMy<G8 s
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public PaginationSupport findPageByCriteria 91up^
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(final DetachedCriteria detachedCriteria, finalint {FWyu5.
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startIndex){ rvic%bsk
return findPageByCriteria Ah-8"`E
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(detachedCriteria, PaginationSupport.PAGESIZE, }W$8M>l
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startIndex); +Hj/0pp
} XLm@etf
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public PaginationSupport findPageByCriteria 0Uw
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(final DetachedCriteria detachedCriteria, finalint EKuSnlTXba
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pageSize, S[mM4et|
finalint startIndex){ ^av6HFQ
return(PaginationSupport) p<KIF>rf|
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getHibernateTemplate().execute(new HibernateCallback(){ zDDK
publicObject doInHibernate R\5Vq$Q
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(Session session)throws HibernateException { QR"bYQ
Criteria criteria = Nb;H`<JP
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detachedCriteria.getExecutableCriteria(session); DyfsTx
int totalCount = 6tn+m54_
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((Integer) criteria.setProjection(Projections.rowCount S`iR9{+&
9#k0_vDoW
()).uniqueResult()).intValue(); &[_ZXVva~
criteria.setProjection :.uk$jx
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(null); } ptMjT{9
List items = \a))
)(m0cP{7
criteria.setFirstResult(startIndex).setMaxResults gnLn7?
Hi7y(h?wj
(pageSize).list(); lb~E0U`\E`
PaginationSupport ps = 8IGt4UF&?
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new PaginationSupport(items, totalCount, pageSize, \Q&,ISO\
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startIndex); h*w6/ZL1
return ps; i sW\MB]
} <7)Fh*W@
}, true); NfzF.{nh
} gU1 #`r>[)
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public List findAllByCriteria(final A\$
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DetachedCriteria detachedCriteria){ Rc[ 0aj:
return(List) getHibernateTemplate )oU)}asY
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().execute(new HibernateCallback(){ L{8;Ud_2r
publicObject doInHibernate vF4]ux&
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(Session session)throws HibernateException { $t/rOo9cV
Criteria criteria = S%mfs!E>
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detachedCriteria.getExecutableCriteria(session); {Wv%zA*8
return criteria.list(); ~i0R^qfr
} TgfrI
}, true); iwF9[wAft
} 4n0xE[-
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public int getCountByCriteria(final y\c"b-lQX
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DetachedCriteria detachedCriteria){ p9qKLJ*.C
Integer count = (Integer) S*
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getHibernateTemplate().execute(new HibernateCallback(){ kkCZNQ~I
publicObject doInHibernate (Ddp|a"b
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(Session session)throws HibernateException { 5|8^9Oe5
Criteria criteria = DcD{*t?x
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detachedCriteria.getExecutableCriteria(session); c64v,Hj9
return FnFb[I@eu
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criteria.setProjection(Projections.rowCount ]wVk+%e
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()).uniqueResult(); 9~\kF5Q"
} Q \hY7Xq'
}, true); IE2"rQ T
return count.intValue(); m#!=3P7T
} B%s7bS
} iq$$+y,
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用户在web层构造查询条件detachedCriteria,和可选的 4,Ic}CvM
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 |SZo'
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PaginationSupport的实例ps。 V9yl4q-bL
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ps.getItems()得到已分页好的结果集 {7hLsK[])
ps.getIndexes()得到分页索引的数组 2F{hg%
ps.getTotalCount()得到总结果数 <W8t|jt
ps.getStartIndex()当前分页索引 G3P&{.v
ps.getNextIndex()下一页索引 }|OaL*|u
ps.getPreviousIndex()上一页索引 HSUI${<
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 |y;}zQB-dH
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 #AkV/1Y
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一下代码重构了。 C&LBr|
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我把原本我的做法也提供出来供大家讨论吧: E907fX[R~
V]OmfPve
首先,为了实现分页查询,我封装了一个Page类: :o-,SrORM
java代码: zLs|tJOVp
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/*Created on 2005-4-14*/ S1Z2_V
package org.flyware.util.page; TNCgaTJ{h
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/** <U5wB]]
* @author Joa Va,<3z%O<
* Ac2(O6
*/ <~}7Mxn%x@
publicclass Page { 1wzqGmjmt
w\54j)rb
/** imply if the page has previous page */ _It ,%<3
privateboolean hasPrePage; ~7~~S*EQ
\P} p5k[
/** imply if the page has next page */ hT$~ygQ
privateboolean hasNextPage; 9CA^B2u
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/** the number of every page */ 4c
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privateint everyPage; B\J^=W+`
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/** the total page number */ d(vsE%/!
privateint totalPage; ?88[|;b3
s]m o$ _na
/** the number of current page */ bCref$|
privateint currentPage; Y2xL>F
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/** the begin index of the records by the current M02uO`Y9
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query */ FX9F"42@
privateint beginIndex; k(zsm"<q
u@ jX+\
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/** The default constructor */ x~.:64
public Page(){ +/#Ei'do
4}`
} da1]mb=4 5
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/** construct the page by everyPage q o<&J f
* @param everyPage Z%I
* */ 2X:4CC%5
public Page(int everyPage){ wApMzZ(X2y
this.everyPage = everyPage; vG \a1H
} ?Ma~^0
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/** The whole constructor */ sXd8rj:o
public Page(boolean hasPrePage, boolean hasNextPage, ]f]<4HD=i
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int everyPage, int totalPage, o)OUWGjb/K
int currentPage, int beginIndex){ 0afei4i~N
this.hasPrePage = hasPrePage; DE2a5+^
this.hasNextPage = hasNextPage; qc#)!
this.everyPage = everyPage; p{PE@KO:
this.totalPage = totalPage; )xb|3&+W
this.currentPage = currentPage; Q}S_%I}u:
this.beginIndex = beginIndex; a_h]?5
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}
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/** S(\9T1DVe
* @return C/(M"j M
* Returns the beginIndex. U^qt6$bK
*/ >DPB!XA3
publicint getBeginIndex(){ : Sq?a0!S
return beginIndex; QdLYCR4f
} /m!Cc/Hv
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/** LN_xq&.
* @param beginIndex z5W@`=D
* The beginIndex to set. Q[+ac*F=Y
*/ :SxW.?[%u
publicvoid setBeginIndex(int beginIndex){ K-&V,MI
this.beginIndex = beginIndex; `bc;]@"
} [frq
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/** <(vCiH9~P
* @return U35AX9/
* Returns the currentPage. !~Q2|r
*/ au,t%8AC
publicint getCurrentPage(){ vP+@z-O
return currentPage; %r4q8-
} p">EHWc}D
:8A!HI}m{
/** R0oKbs{
* @param currentPage &sF^Fgg{
* The currentPage to set. fvb=#58N_
*/ c*UvYzDZL
publicvoid setCurrentPage(int currentPage){ r=c<--_@
this.currentPage = currentPage; Jjl`_X$CB
} ?:}Pa<D&K
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/** u( 9X
* @return X(GV6mJ4
* Returns the everyPage. agY5Dg7
*/ w`#fH
publicint getEveryPage(){ {,f[r*{Y
return everyPage; ;:_(7|
} h*'d;_(,
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/** [2H[5<tH
* @param everyPage nO_!:6o".
* The everyPage to set. F!R2_89iy
*/ jM\ %$_/
publicvoid setEveryPage(int everyPage){ 6K//1U$
this.everyPage = everyPage; %^')G+>i
} lM&UFEl-\
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/** q2Rf@nt
* @return P CsK()
* Returns the hasNextPage. v$JLDt_
*/ #ko6L3Pi
publicboolean getHasNextPage(){ _FFv#R*4
return hasNextPage; =AzOnXW:S
} x:C@)CAr
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/** C M^r|4K
* @param hasNextPage dgY5ccP
* The hasNextPage to set. I9,8HtnA
*/ JilKZQmk
publicvoid setHasNextPage(boolean hasNextPage){ H` Lu"EK
this.hasNextPage = hasNextPage; +Z$a1Y@
} 4L$};L
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/** n531rkK-
* @return :P"9;$FY
* Returns the hasPrePage. m>O2t-
*/ dL(4mR8
publicboolean getHasPrePage(){ .Map
return hasPrePage; y0y+%H-
} b8e*Pv/
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/** iI}nW
* @param hasPrePage (Y>U6
* The hasPrePage to set. ]Qc: Zy3
*/ g.=!3e&z%
publicvoid setHasPrePage(boolean hasPrePage){ Y& m<lnB
this.hasPrePage = hasPrePage; <@%ma2
} ]svw
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/** s7AI:Zv
* @return Returns the totalPage. 1k`|[l^
* )biX8yqhR
*/ ?SB5b ,
publicint getTotalPage(){ ,qYf#fU#7
return totalPage; ?9CIWpGjU
} Km%8Yw0+
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/** Aw5K3@Ltz
* @param totalPage 9.jG\i
* The totalPage to set. ;Xz(B4 N~o
*/ ;,R[]B01u
publicvoid setTotalPage(int totalPage){ 9B&
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this.totalPage = totalPage; t<8z08
} 5NFq7&rJ6
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} ;%M2x5
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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 6
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个PageUtil,负责对Page对象进行构造: iz,]%<_PE
java代码: 9$n+-GSK
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/*Created on 2005-4-14*/ q|?`Gsr
package org.flyware.util.page; 9@JlaY)0
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import org.apache.commons.logging.Log; \z&03@Sw
import org.apache.commons.logging.LogFactory; GP0[Y
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/** +qE,<c}}
* @author Joa 2(@LRl>:
* ^U R-#WaQ
*/ mYzsTUq
publicclass PageUtil { R?1idl)
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privatestaticfinal Log logger = LogFactory.getLog ly9x1`?$
L{4),65
(PageUtil.class); <>ZBW9
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/** $w 5#2Za
* Use the origin page to create a new page u?LW+o
* @param page ahK?]:&QO
* @param totalRecords ,AGM?&A
* @return O7Y
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*/ 4f_ZY5=
publicstatic Page createPage(Page page, int IBn'iE[>
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totalRecords){ a>-}\GXTA
return createPage(page.getEveryPage(),
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page.getCurrentPage(), totalRecords); <(u3+`f1s
} #`fi2K&]j
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/** A52LH,
* the basic page utils not including exception ?0 KiR?
:pL1F)-*
handler o(v"?Y 6
* @param everyPage yoq\9* ?u^
* @param currentPage "u3fs2
* @param totalRecords llTQ\7zP
* @return page 1[fkXO{
*/ [="g|/M)
publicstatic Page createPage(int everyPage, int +R{A'Yl[(
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O{
currentPage, int totalRecords){ K#m\qitb
everyPage = getEveryPage(everyPage); |ec(z
currentPage = getCurrentPage(currentPage); T6/$pJl
int beginIndex = getBeginIndex(everyPage, XC+F! R
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currentPage); *Dd(+NI
int totalPage = getTotalPage(everyPage, 2ZTyo7P
nsr
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totalRecords); 9^b7jw
boolean hasNextPage = hasNextPage(currentPage, 6I5[^fv45G
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totalPage); }5fI*v
boolean hasPrePage = hasPrePage(currentPage); 'aSZ!R
~8Dd<4?F]
returnnew Page(hasPrePage, hasNextPage, H$=h-
everyPage, totalPage, ;ZE<6;#3IP
currentPage, dZ;~b(CA
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beginIndex); 6a 2w-}Fs
} {$u@6&
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privatestaticint getEveryPage(int everyPage){ n'x`oI)-
return everyPage == 0 ? 10 : everyPage; |~=?vw<W
} RJ`/qXL
6U,U[MWJ
privatestaticint getCurrentPage(int currentPage){ W:;`
return currentPage == 0 ? 1 : currentPage; x9{Sl[2&
} ~YT>:Np
!kHyLEV
privatestaticint getBeginIndex(int everyPage, int n_!]B_Vd$
o}AqNw60v
currentPage){ 9cw4tqTm
return(currentPage - 1) * everyPage; HpjIp.
} l66ipgw_^I
zvQ^f@lq2
privatestaticint getTotalPage(int everyPage, int +=29y@c
m;tY(kO
totalRecords){ tKqCy\-q
int totalPage = 0; "#eNFCo7k
=-1^K
if(totalRecords % everyPage == 0) |0vHy7CE
totalPage = totalRecords / everyPage; i5~ /+~
else aBA#\eV
totalPage = totalRecords / everyPage + 1 ; ~M9n<kmE
nF!_q;+Vp
return totalPage; 4[f7X4d$
} MkV*+LXC
` $x#_-Hn
privatestaticboolean hasPrePage(int currentPage){ c_8 mQ
return currentPage == 1 ? false : true; &0<R:K ?>N
} /xm} ?t0U
Iy1Xn S*
privatestaticboolean hasNextPage(int currentPage, dW=D]
8Q)mmkI\=
int totalPage){ DGuUI}|)
return currentPage == totalPage || totalPage == %>z8:oJ
5)zh@aJ@
0 ? false : true; [XU{)l
} MFdFZkpiV
F+m4
]zR;%p
} `\u),$
'8pPGh9D
s?\9i6
v.^
'x
q
]R @:a/
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
=Az[
6_}){ZR
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 )1yUV*6
][K8\
做法如下: TboHP/
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 g#<?OFl
6%hEs6-R
的信息,和一个结果集List: 9qO:K79|
java代码: '*{Rn7B5
LVcy.kU@]
f!kdcr=/"
/*Created on 2005-6-13*/ k49n9EX
package com.adt.bo; #Uk6Fmu]
w0%ex#lkm
import java.util.List; WF.$gBH"
B46H@]d#7K
import org.flyware.util.page.Page; @KRn3$U
\7w85$
/** v@1Jhns
* @author Joa Y%cA2V\#m
*/ XlcDF|?{.
publicclass Result { zgOwSg8
k.f:nv5JO
private Page page; Ox1QP2t6Y
?BZ`mrH^
private List content; D7'0o`|
k 5kX
/** _[Wrd?Z
* The default constructor eeR@p$4i
*/ +uXnFf d^
public Result(){ bH]!~[
super(); $>37PVVW
} weadY,-H8
h/~BUg'
/** ,colGth54
* The constructor using fields MM$"6Jor
* gx
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* @param page ^u&Khc~
y
* @param content $ =a$z"
*/ l'8wPmy%N
public Result(Page page, List content){ W%QtJB1)
this.page = page; JJ06f~Iw[
this.content = content; Eu~wbU"%
} N>\?Aeh
X.5LB!I)
/** m)w-mc
* @return Returns the content. -%$
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*/ ;P#*R3
publicList getContent(){ [`dipLkr
return content; Upen/1 bA
} r}Av"
CUcjJ|MZ
/** V2skr_1
* @return Returns the page. 5W-M8dc6
*/ IcA~f@
public Page getPage(){ .?]_yX
return page; eR;0pWVl
} aBLb i
2 -8:qmP(
/** 'mR+W{r
* @param content BBj"}~da
* The content to set. jo#F&
*/ vH8%a8V
public void setContent(List content){ cNvcpv
this.content = content; )S?}huX
} EOC"a}Cq-
y Dw!u[:
/** i|'t!3I^m
* @param page brot&S2P><
* The page to set. l))IO`s=_
*/ M lwQ_5O
publicvoid setPage(Page page){ 8
\Oiv$r
this.page = page; kJFHUR
} OO>2oH
} ~Wv?p4
+06j+I
F
tjm@:X
i(rY'o2 BN
^123.Ru|t
2. 编写业务逻辑接口,并实现它(UserManager, 4F!d V;"Z(
{*Pp^r
UserManagerImpl) $S{j}74[
java代码: 3J<,2
"<#:\6aym
pXa? Q@6
/*Created on 2005-7-15*/ \>k+Oyj
package com.adt.service; JK^;-&
Z]d]RL&r
import net.sf.hibernate.HibernateException; c-d}E!C:
!f6
import org.flyware.util.page.Page; T(F8z5s5
{>g{+Eq
import com.adt.bo.Result; Z-:T')#Cf
|yS %
/** OYSq)!:
* @author Joa S#kYPe
*/ F%P"T%|
publicinterface UserManager { zG{P5@:.R
L+N\B@ 0-
public Result listUser(Page page)throws .exBU1Yk@
;6:9 EEd
HibernateException; 1_WP\@O
_ _!LTpp
} DSQ2|{
t0,=U8]w
PriLV4?
G 9|2
KUG
60;_^v
java代码: 7r&lW<:>
djH&)&q!
NOg/rDs'{
/*Created on 2005-7-15*/ Sl/]1[|mb
package com.adt.service.impl; !c`&L_ "!
`JO>g=,4
import java.util.List; @^T~W^+
f0vO(@I
import net.sf.hibernate.HibernateException; C$q};7b1N
FQJiLb._Z
import org.flyware.util.page.Page; @Ddz|4 vEi
import org.flyware.util.page.PageUtil; FRuPv6
((C|&$@M
import com.adt.bo.Result; ! ui
import com.adt.dao.UserDAO; ~Oa$rqu%m
import com.adt.exception.ObjectNotFoundException; )X-'Q -
import com.adt.service.UserManager; !NH(EWER
ckMG4
3i\j
/** 2TUV9Z
* @author Joa <3!Al,!ej@
*/ ;89kL]
publicclass UserManagerImpl implements UserManager { 7mq&]4-G
-nXP<v=V
private UserDAO userDAO; Q66 +
JcUU#>
/** ulxfxfd
* @param userDAO The userDAO to set. {;DAKWm@T
*/ 5CZyA`3V^5
publicvoid setUserDAO(UserDAO userDAO){ +@=V}IO
this.userDAO = userDAO; 4^uSW&`;/
} 1l$2T
y+
=
kV+^1@"
/* (non-Javadoc) )O" E#%
* @see com.adt.service.UserManager#listUser ''YqxJ fb
+=jS!
(org.flyware.util.page.Page) kh9'W<tE
*/ W?5')
public Result listUser(Page page)throws rw,Ylr:3
ka~_iUU4
HibernateException, ObjectNotFoundException { `p&[b]b
int totalRecords = userDAO.getUserCount(); kzKej"a;
if(totalRecords == 0) tsAV46S
throw new ObjectNotFoundException SK
lvZ
]:OrGD"
("userNotExist"); uX*2Rs$s
page = PageUtil.createPage(page, totalRecords); K f/[Edn
List users = userDAO.getUserByPage(page); !gve]>M
returnnew Result(page, users); ,c4HicRJ#
} *Jgi=,!m
J-hJqR*;K
} G9f6'5 O
i'm<{v
xIGq+yd(
?qNU*d
#B;P4n3
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 !l9{R8m>eJ
f`n4'dG
询,接下来编写UserDAO的代码: I.n,TJoz4J
3. UserDAO 和 UserDAOImpl: j{%;n40$
java代码: zY*9M3(X
eR$@Q
rP:g`?*V
/*Created on 2005-7-15*/ 0G+Q^]0
package com.adt.dao; E`.xu>Yyj
hx9{?3#
import java.util.List; )i~AXBt}
)A\
ZS<@Z7
import org.flyware.util.page.Page; /W/e%.
<0})%V?-
import net.sf.hibernate.HibernateException; C^L+R7
FJ_7<4ET
/** ;Z]Wj9iY
* @author Joa `,qft[1
*/ 4j#y?^s
publicinterface UserDAO extends BaseDAO { ,U~A=bsa
i"h\*B=
publicList getUserByName(String name)throws 'X;cgAq8(
h[W`P%xZ
HibernateException; pey=zR!
wXIRn?z
publicint getUserCount()throws HibernateException; geme_
k =5k)}i
publicList getUserByPage(Page page)throws F\m^slsu7=
pF{jIXu
HibernateException; l7|z]v-
.9bi%=hP
} &t=:xVn-M
ANhqS
V$?6%\M^*
qYK^S4L
-c_l
n K
java代码: Tqt-zX|>
Gyq 6?
)x6&Y
/*Created on 2005-7-15*/ e9{ii2M
package com.adt.dao.impl; "wgPPop
"t0^4=c+7
import java.util.List; M& ZKc
!D=!
import org.flyware.util.page.Page; ZC?~RXL(
76l. {TXF
import net.sf.hibernate.HibernateException; uj8saNu
import net.sf.hibernate.Query; if*V-$[I
5i[O\@]5
import com.adt.dao.UserDAO; UD-+BUV
9^a|yyzL
/** T8S&9BM7
* @author Joa Gdow[x
*/ |/Vq{gxp+
public class UserDAOImpl extends BaseDAOHibernateImpl 2u]G]:ml
y!b"Cj
implements UserDAO { evyjHc Cx
7nB4(A2[S4
/* (non-Javadoc) MSCH6R"5
* @see com.adt.dao.UserDAO#getUserByName j,OA>{-$
Qsbyy>o)
(java.lang.String) Ic'D#m
*/ YuhfPa
publicList getUserByName(String name)throws QD-\'Bp/X
e|tx`yA
HibernateException { HM% +Y47a
String querySentence = "FROM user in class O C&BJNOi
:W)lt28_
com.adt.po.User WHERE user.name=:name"; !KI^Z1dP(
Query query = getSession().createQuery 3eUi9_s+
n/v.U,f&l@
(querySentence); v.RA{a 9
query.setParameter("name", name); 0Z2XVq~T$
return query.list(); JZ}zXv
} 7&id(&y/
fq>{5ODO
/* (non-Javadoc) LVUA"'6V
* @see com.adt.dao.UserDAO#getUserCount() kwp%5C-S
*/ "nz\YQdg
publicint getUserCount()throws HibernateException { f>Rux1Je4
int count = 0; Z`kVyuQ
String querySentence = "SELECT count(*) FROM ./I? |ih
2D:/.9= 8v
user in class com.adt.po.User"; ]WNY"B>+
Query query = getSession().createQuery ^x0N]/
,#XXwm ^I
(querySentence); huZ5?'/Fg
count = ((Integer)query.iterate().next }k.yLcXM
`\@n&y[`7
()).intValue(); 9 m8KDB[N
return count; ?$`kT..j,u
} (g@X.*c8
f
I%8@ :
/* (non-Javadoc) uG -+&MU?
* @see com.adt.dao.UserDAO#getUserByPage @q!T,({kx
/,SVG1
(org.flyware.util.page.Page) 6Gg`ExcT5
*/ Lv@WI6DM
publicList getUserByPage(Page page)throws m$C1Ea-wnT
RR=WD -l
HibernateException { E q4tcZ
String querySentence = "FROM user in class |fyzb=Lg
kB?/_a`]
com.adt.po.User"; :2KPvp7?
Query query = getSession().createQuery J<L\IP?%
K bQXH!J
(querySentence); u3Z]!l
query.setFirstResult(page.getBeginIndex()) 9Tr ceL;
.setMaxResults(page.getEveryPage()); @_t=0Rc
return query.list(); <b'*GBw$
} 5$!idfDr|m
)o:sDj`b]
} CF3x\6.q}
HPu+ 4xQV
khjdTq\\
[^GBg>k
W;8A{3q%N0
至此,一个完整的分页程序完成。前台的只需要调用 Pm#/j;
,FP0n
userManager.listUser(page)即可得到一个Page对象和结果集对象 Xl1% c7r.1
dLGHbeZ[(
的综合体,而传入的参数page对象则可以由前台传入,如果用 J;<dO7 j5
t]Ln(r
webwork,甚至可以直接在配置文件中指定。 T*@o?U
4r83;3WXs
下面给出一个webwork调用示例: EKO'S+~
java代码: "c} en[
6p@[U>`
Kn3Xn`P?
/*Created on 2005-6-17*/ J|hVD
package com.adt.action.user; s)E8}-v
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import java.util.List; p&$PsgR
R|}4H*N
import org.apache.commons.logging.Log; UhDf6A`]
import org.apache.commons.logging.LogFactory; Pc&dU1
import org.flyware.util.page.Page; ]#DCO8Vk
vN
v'%;L
import com.adt.bo.Result; b00$3,L
import com.adt.service.UserService; l
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import com.opensymphony.xwork.Action; m+8:_0x "
(Z @dz
/** i`f!) 1
* @author Joa $DfK}CT
*/ \IC^z
publicclass ListUser implementsAction{ ah<p_qe9|
.|u`s,\
privatestaticfinal Log logger = LogFactory.getLog a_/4 ^+
\VEnP=*:W
(ListUser.class); !4#qaH-Q
|J`v
w
private UserService userService; jmgkY)rb R
z
&P1C,n)
private Page page; yogL8V-^4
m;4ti9
privateList users; \"RCJadK
\tvL<U"'
/* &-o5lrq
* (non-Javadoc) ID`C
* irm4lb5
* @see com.opensymphony.xwork.Action#execute() ChUE,)
*/ [*It' J^
publicString execute()throwsException{ 6q'Q?Uw^
Result result = userService.listUser(page); 0+1!-Wo
page = result.getPage(); Vb#a ,t
users = result.getContent(); n6,YA2yZO
return SUCCESS; T<>B5G~%
} {T^D&i# o
T=~d.&J
/** FXY>o>K%h
* @return Returns the page. gCsN\z
*/ <]%6x[
public Page getPage(){ Qer}eg`R
return page; 7 z+Ngt' !
} @`SlOKz!=
//}KWz
/** _E^ !,Wz
* @return Returns the users. *Y ?&N2@c
*/ ,Mn?h\
publicList getUsers(){ sFRQFX0XoY
return users; `S]DHxS
} :rN5HOg^9
:1!k*5
/** +Jq~39
* @param page Ehtb`Ms
* The page to set. v*@R U
*/ ru*}lDJ
publicvoid setPage(Page page){ \.`{nq
this.page = page; \'P79=AU
} |+aD%'|
]7%+SH,RdD
/** 'u%SI]*;>
* @param users YM +4:P2
* The users to set. .!g
*/ X0]5I0YP
publicvoid setUsers(List users){ @9h6D<?
this.users = users; Z}r9jM
} D{iPsH6};5
\.MPjD
/** ,mD{4 >7
* @param userService $7&t`E)qY
* The userService to set. WeS$$:ro
*/ P<R'S
publicvoid setUserService(UserService userService){ PWN$x`h g[
this.userService = userService; 7V;wCm#b
} >L88`
} /cZ-+cu
Wg=4`&F^
0/b3]{skK
qfB!)Y
Vg1MA
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, d)v'K5
:.F;LF&
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 XbW 1`PH
-F';1D!l%
么只需要: bBXUD;$
java代码: 2@$`xPg
r[kmgPld
3rVWehCv
<?xml version="1.0"?> 4mwA o
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork uBxs`'C
P&9&/0r=_
1.0//EN" "http://www.opensymphony.com/xwork/xwork- k(3FT%p
sKGR28e
1.0.dtd"> n~v*
Q`(h
<xwork> jR mo9Bb2
\Qe`>nA
<package name="user" extends="webwork- l=ZX9<3
JReJlDu
interceptors"> IM&l%6[).
4j-%I7
<!-- The default interceptor stack name s7na!A[
oD7^9=#
--> _[ufH*
<default-interceptor-ref >$N ?\\#
#P-T4R
name="myDefaultWebStack"/> aX(Y
`g)|
"| KD$CY
<action name="listUser" DzG$\%G2R}
\kVi&X=q:
class="com.adt.action.user.ListUser"> R\n*O@E
v3
<param >R2o7~
gjex; h
name="page.everyPage">10</param> 1A;f[Rze
<result cR/z; *wr7
OE_A$8L
name="success">/user/user_list.jsp</result> ];au!
_o
</action> x_BnWFP
J+0T8
?A
</package> $ 2PpG|q
!6DH6<HC
</xwork> !ZTBiC5R
3q:>NB<
{N 0i
3e
s
Vh5Z'4N
2f7]=snCG
zUd{9B$
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 zFeo8S
/WJ+e
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。 R7~#7qKQB
X1~ WQ?ww
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 k5]`:k6
5Ak6 q(\
KeE)9e
Y@R9+7!
,lr\XhO
我写的一个用于分页的类,用了泛型了,hoho EZg$mp1
b0!ZA/YC-
java代码: Jx4"~ 4
%tJ@)
!O*uQB
package com.intokr.util; xE%sPWbj
)NL_))\
import java.util.List; 29AWg(9?aS
LKe~
/** t{RdqAF
* 用于分页的类<br> =6LF_=}
* 可以用于传递查询的结果也可以用于传送查询的参数<br> $g!~T!p=
* oBZzMTPe
* @version 0.01 i4^1bd
* @author cheng -|nHwSrCZ/
*/ Iji9N!Yx
public class Paginator<E> { oV Hh
privateint count = 0; // 总记录数 \?rBtD(
privateint p = 1; // 页编号 &WAJ;7f
privateint num = 20; // 每页的记录数 %P tdFz$
privateList<E> results = null; // 结果 i2(lqhaP
l!YjDm{E
/** $3Srr*
* 结果总数 qJf=f3
*/ :Vl2\H=P
publicint getCount(){ ;Alw`'
return count; EwH_k
} <\C/;
}qn@8}
publicvoid setCount(int count){ i*-L_!cc:
this.count = count; H_<hZUB
} QvjOOc@k~n
y(uE
/** ej&ZE
n
* 本结果所在的页码,从1开始 La#otuw+?
* STY\c5
* @return Returns the pageNo. :r,o-D
*/ `'
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publicint getP(){ l&LrcM
return p; UpIt"+d2&
} yCLDJ%8
|#_`aT"
/** Eggdj+
* if(p<=0) p=1 /WWD;keP5
* :Mq-4U.e
* @param p q=(.N>%
*/ 5<?s86GHh'
publicvoid setP(int p){ |'" 17c&
if(p <= 0) @ATJ|5.gr
p = 1; fKN&0N|^R
this.p = p; :^oF0,-qZ
} KoL3CA"N
gV-x1s+
/** x]%'^7#v)
* 每页记录数量 KaGG4?=V
*/ }"CX`
publicint getNum(){ S LSbEm
return num; }HC6m{vH(
} +{F2hEYP
~KF>Jow?Y
/** P&0o~@`cL
* if(num<1) num=1 I"1H]@"=
*/ mcB8xE
publicvoid setNum(int num){ /9..hEq^
if(num < 1) NiCB.a
num = 1; !?u{2D
this.num = num; O)E8'Oe"Q
} ;mw$(ZKa#
_K5R?"H0
/** UZ` <D/
* 获得总页数 +^\TG>le
*/ 1ehl=WN
publicint getPageNum(){ i^zncDMA
return(count - 1) / num + 1; sa26u`?
} 4Y#F"+m.]
'**dD2
n
/** sWc_,[b
* 获得本页的开始编号,为 (p-1)*num+1 s
v}o%
*/ eAPNF?0yh
publicint getStart(){ CCQ38P@rv
return(p - 1) * num + 1; a\BV%'Zqg
} fI([vI
~&
@UH
/** 71GyMtX
* @return Returns the results. #-*#? -
*/ 0~:Eo89
publicList<E> getResults(){ Z:2a_Atm
return results; HpX ;:/I
} ;I^+u0ga
g*& |Eq/
public void setResults(List<E> results){ c'8pTP%[
this.results = results; c4'k-\JvT
} d@ ?++z
v.Y?<=E+<d
public String toString(){ ~;#OQ[
StringBuilder buff = new StringBuilder RMfKM!
vE
)=vQrMyB
(); 'q_^28rK
buff.append("{"); (-:lO{@FsC
buff.append("count:").append(count); D;bHX
buff.append(",p:").append(p); (v'#~ )R_`
buff.append(",nump:").append(num); F^/1 u
buff.append(",results:").append 25zmde~ w
&eqeQD6
(results); *49lM;
buff.append("}"); [$<\*d/
return buff.toString(); ..5rW0lr
} (&)PlIi7
8wXnc%
} jrKRXS
UbnX%2TW
Hido[