Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 kmJ{(y)w
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 =)56]ki}
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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 z3l=aAw8
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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 J 4$^Hr
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分页支持类: L*ZC`
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java代码: oB9t&yM
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package com.javaeye.common.util; b\/:-][
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import java.util.List; j8@Eqh
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publicclass PaginationSupport { zVLv-U/=d
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publicfinalstaticint PAGESIZE = 30; Tct[0B
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privateint pageSize = PAGESIZE; Wsn}Y-x
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privateList items; T-Od|T@[
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privateint totalCount; v1hrRf2<
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privateint[] indexes = newint[0]; K)2ZH@
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privateint startIndex = 0; ^}XKhn.S'
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public PaginationSupport(List items, int _VU/j9<+
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totalCount){ d*26;5~\
setPageSize(PAGESIZE); I*e85wef
setTotalCount(totalCount); L[zg2y
setItems(items); K
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setStartIndex(0); cH>rS\|Y
} {mPaloA
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public PaginationSupport(List items, int dw)SF,
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totalCount, int startIndex){ W4yNET%l,
setPageSize(PAGESIZE); Ti/t\'6
setTotalCount(totalCount); eTI<WFRc_
setItems(items); kJ6=T6s
setStartIndex(startIndex); !g /&ws&
} yD
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public PaginationSupport(List items, int JZp*"UzQr
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totalCount, int pageSize, int startIndex){ !dfc1 UjB
setPageSize(pageSize); u49zc9
setTotalCount(totalCount); ZF
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setItems(items);
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setStartIndex(startIndex); :+ef|,:`/
} C+-GE9=
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publicList getItems(){ "J]_B
return items; D'aq^T'
} H{'<v|I
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publicvoid setItems(List items){ 0bxB@(NO
this.items = items; 8P r H"pI
} OKfJ
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publicint getPageSize(){ V,bfD3S3
return pageSize; oxE'u<
} .lfKS!m2
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publicvoid setPageSize(int pageSize){ ]]{$X_0n
this.pageSize = pageSize; 5uMh#dm^
} M:|Z3p K
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publicint getTotalCount(){ JqTkNKi/s
return totalCount; ZSq7>}
} i"%X[(U7
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publicvoid setTotalCount(int totalCount){ y0qrl4S)v
if(totalCount > 0){ v4!zB9d
this.totalCount = totalCount; *@fR36
int count = totalCount / z]ZhvH7-
7''l\3mIn
pageSize; \B"5 Kp<
if(totalCount % pageSize > 0) J@Eqqyf"
count++; $5y%\A
indexes = newint[count]; U>6MT@\
for(int i = 0; i < count; i++){ WyVFhAuU
indexes = pageSize * 8;;!2>N
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} d_=@1JM>
}else{ cVJ"^wgBt
this.totalCount = 0; {~>?%]tf
}
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} C4],7"Sw
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publicint[] getIndexes(){ {]<l|qK
return indexes; r(iT&uz
} QlJ
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publicvoid setIndexes(int[] indexes){ b{<qt})
this.indexes = indexes; OiX:h#
} |t*(]U2O0
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publicint getStartIndex(){ IY6DZP
return startIndex; /PG+ s6
} Mg;%];2Nt
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publicvoid setStartIndex(int startIndex){ }]_/:KUt
if(totalCount <= 0) bqp6cg\p
this.startIndex = 0; zWpJ\/k~
elseif(startIndex >= totalCount) )orVI5ti
this.startIndex = indexes 9Z]~c^UB
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[indexes.length - 1]; SLp &_S@4
elseif(startIndex < 0) 3ny>5A!;2
this.startIndex = 0; {'VP_ZS1v
else{ =r"8J5[f
this.startIndex = indexes [2?|BUtD[
^T@ (`H4@
[startIndex / pageSize]; 73B,I 0U
} j78WPG
} lo*OmAF
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publicint getNextIndex(){ X.hU23w
int nextIndex = getStartIndex() + D/)wg$MI
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pageSize; )9F-h8
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if(nextIndex >= totalCount) wBZ=IMDu\
return getStartIndex(); twElLOE
else >QO^h<.>
return nextIndex; 1Q\P]
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} 0Jz H dz
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publicint getPreviousIndex(){ /ivcqVu]
int previousIndex = getStartIndex() - l?pF?({
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pageSize; [8|Y2Z\N
if(previousIndex < 0) 0/K?'&$yvb
return0; hhd%j6
else &_Kb;UVRj
return previousIndex; ]D?//
} .4on7<-a
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}
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抽象业务类 -e<d//>
java代码: MzjV>.
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/** tLCu7%P>
* Created on 2005-7-12 Gk_%WY*
*/ .T~<[0Ex+U
package com.javaeye.common.business; p3tu_If
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import java.io.Serializable; <0lXJqd
import java.util.List; ^(z7?T
cs[_TJo
import org.hibernate.Criteria; +;z^qn
import org.hibernate.HibernateException; ;R[ xo!
import org.hibernate.Session; +m?;,JGt
import org.hibernate.criterion.DetachedCriteria; !ieMhJ5r
import org.hibernate.criterion.Projections; eC%uu
import ,TeJx+z^
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org.springframework.orm.hibernate3.HibernateCallback; kk|7{83O
import Bmx+QO
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org.springframework.orm.hibernate3.support.HibernateDaoS oCtg{*vp
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upport; 5cc;8i
Xjb 4dip
import com.javaeye.common.util.PaginationSupport; EQQ/E!N8l
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public abstract class AbstractManager extends ~K'e}<-G
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HibernateDaoSupport { 5L ]TV\\
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privateboolean cacheQueries = false; :Y? L*
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privateString queryCacheRegion; `As|MYv
}"}
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publicvoid setCacheQueries(boolean X;2I'
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cacheQueries){ [tN^)c`s/
this.cacheQueries = cacheQueries; yf|,/{S
} (CUrFZT$
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publicvoid setQueryCacheRegion(String $H0diwl9R
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queryCacheRegion){ 2T3TD%
this.queryCacheRegion = L >*
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queryCacheRegion; rbC4/ 9G\
} ^pI&f{q
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publicvoid save(finalObject entity){ tKr.{#)
getHibernateTemplate().save(entity); |aAu4
} bIvF5d>9#K
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publicvoid persist(finalObject entity){ U,G!u =+
getHibernateTemplate().save(entity); B: '}SA{
} C-wwQbdG/
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publicvoid update(finalObject entity){ W|~Jl7hs8Q
getHibernateTemplate().update(entity); BIu%A]e"
} JpI(Vcd
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publicvoid delete(finalObject entity){ B/:+(|
getHibernateTemplate().delete(entity); B~%'YQk
} jwP}{mi*
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publicObject load(finalClass entity, M-#OPj*
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finalSerializable id){ *8QESF9
return getHibernateTemplate().load jb~W(8cj
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(entity, id); 7g* "AEk
} |E&
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publicObject get(finalClass entity, <N4)X"s
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finalSerializable id){ ( M > C
return getHibernateTemplate().get \(4"kY_=
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(entity, id); |JUb 1|gi
} S.: m$s
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publicList findAll(finalClass entity){ ^#6"d+lp
return getHibernateTemplate().find("from JYAtQTOR
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" + entity.getName()); |UudP?E
} \d"uR@$3mG
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publicList findByNamedQuery(finalString }\iH ~T6
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namedQuery){ Z+gG.|"k
return getHibernateTemplate G{ |0}
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().findByNamedQuery(namedQuery); z<3{.e\e
} v+), uj
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publicList findByNamedQuery(finalString query, fZq_]1(/uP
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finalObject parameter){ `Kt]i5[ "
return getHibernateTemplate _v[yY3=3
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().findByNamedQuery(query, parameter); he
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} mY)Y47iL
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publicList findByNamedQuery(finalString query, kVqRl%/3Tb
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finalObject[] parameters){ LR(Q.x
return getHibernateTemplate J~e%EjN5e
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().findByNamedQuery(query, parameters); WR;)
} /Ezx'h3Q
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publicList find(finalString query){ j;BMuLTm1
return getHibernateTemplate().find >qqI6@h]c
$ ]fautQlt
(query); T?DX|?2X
} |}?o=bO
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publicList find(finalString query, finalObject bG|aQ2HW
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parameter){ "mk4O4dF
return getHibernateTemplate().find rUz-\H(-
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(query, parameter); "3?N*,U_
} *EB`~s
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public PaginationSupport findPageByCriteria u2FD@Xq?
&|'t>-de,
(final DetachedCriteria detachedCriteria){ x!i(M>P
return findPageByCriteria {hNvCk
v/s6!3pnl
(detachedCriteria, PaginationSupport.PAGESIZE, 0); H[x$65ND
} 1KI,/ H"SY
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public PaginationSupport findPageByCriteria Cj +{%^#
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(final DetachedCriteria detachedCriteria, finalint S>6f0\F/Y%
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startIndex){ 1Z$` }a
return findPageByCriteria ULJV
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(detachedCriteria, PaginationSupport.PAGESIZE, |Y9mre.Y;
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startIndex); C||9u}Q<
} m4r!Ck|
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public PaginationSupport findPageByCriteria Nr(t5TP^
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(final DetachedCriteria detachedCriteria, finalint Z=|NoDZ
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pageSize, *Bm7>g6
finalint startIndex){ }}Kjb
return(PaginationSupport) kLfk2A;' i
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getHibernateTemplate().execute(new HibernateCallback(){ jI;iTKjB(
publicObject doInHibernate dsiQ~ [
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(Session session)throws HibernateException { DDwj[' R
Criteria criteria = m8:9Uv
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detachedCriteria.getExecutableCriteria(session); N+3]C9 2o
int totalCount = YR? ujN
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((Integer) criteria.setProjection(Projections.rowCount n{1;BW#H
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()).uniqueResult()).intValue(); ~TvKMW6/#
criteria.setProjection b rpsZU
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(null); g)M"Cx.
List items = _=Eb:n+X
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criteria.setFirstResult(startIndex).setMaxResults K
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(pageSize).list();
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PaginationSupport ps = 1!P\x=Nn_
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new PaginationSupport(items, totalCount, pageSize, |H%[tkW6c
7J6D wh{
startIndex); *]#(?W.$w
return ps; |3SM
} 9!u&8#i
}, true); a^xt9o`
} t8:QK9|1
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public List findAllByCriteria(final 'lIj89h<E
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DetachedCriteria detachedCriteria){ U-6pia/o
return(List) getHibernateTemplate ENhKuX
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().execute(new HibernateCallback(){ Wq"5-U;:w
publicObject doInHibernate B ?%g@d-;
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(Session session)throws HibernateException { p2I9t|
Criteria criteria = ;RUod .x
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detachedCriteria.getExecutableCriteria(session); .kf FaK
return criteria.list(); AL{r/h
} eR|u']Em>T
}, true); h( V:-D
} bZ-_Q
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public int getCountByCriteria(final (Z |Nz *<
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DetachedCriteria detachedCriteria){ }|9!|Q
Integer count = (Integer) 3X:)r<
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getHibernateTemplate().execute(new HibernateCallback(){ J-U5_>S
publicObject doInHibernate f j:q>}V
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(Session session)throws HibernateException { kW4B
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Criteria criteria = SCq:jI
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detachedCriteria.getExecutableCriteria(session); ;_iDiLC;
return >[r ,X$]
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criteria.setProjection(Projections.rowCount f =T-4Of
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()).uniqueResult(); ; nc3O{rU
} jzb%?8ZJ
}, true); X6-;vnlKN
return count.intValue(); ttd
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} n]x%xnt
} Wo2W/{
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用户在web层构造查询条件detachedCriteria,和可选的 ]9lR:V
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )N3XbbV
ZE:!>VXa87
PaginationSupport的实例ps。
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ps.getItems()得到已分页好的结果集 sIzy/W0iV
ps.getIndexes()得到分页索引的数组 _~.S~;o!b
ps.getTotalCount()得到总结果数 0Z1';A3
ps.getStartIndex()当前分页索引 oYAHyCkVq
ps.getNextIndex()下一页索引 g@|2z
ps.getPreviousIndex()上一页索引 Qpocj:
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 h|%a}])G)
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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 ZtGtJV"H
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一下代码重构了。 cD ?'lB-
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我把原本我的做法也提供出来供大家讨论吧: Mhu|S)hn
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首先,为了实现分页查询,我封装了一个Page类: dLbSvK<(I
java代码: vLIaTr gz
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/*Created on 2005-4-14*/ 0y`r.)G
package org.flyware.util.page; %[x
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/** ."Q}2
* @author Joa s"~3.J
* -"6Z@8=
*/ +1nzyD_E
publicclass Page { [Om,Q<
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/** imply if the page has previous page */ +-NH
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privateboolean hasPrePage;
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/** imply if the page has next page */ D"CU J?
privateboolean hasNextPage; ^$s&bH'8
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/** the number of every page */ l4ru0V8s7
privateint everyPage; yof8L WXx
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/** the total page number */ nh+Hwj#(x
privateint totalPage; *tfD^nctO
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/** the number of current page */ 7Y5.GW\^
privateint currentPage; $r)NL
+
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/** the begin index of the records by the current ART0o7B
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query */ 1Gy
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privateint beginIndex; Xi;<O&+
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/** The default constructor */ )Em`kle
public Page(){ " c+$GS
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} {DZ xK(
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/** construct the page by everyPage iK!FVKi}
* @param everyPage 6!SW]#sD
* */ l{*Ko~g
public Page(int everyPage){ <H$!OPV
this.everyPage = everyPage; QH_Ds,oH=
} 5_1\{lP
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/** The whole constructor */ }WhRJr`a
public Page(boolean hasPrePage, boolean hasNextPage, Dus!Ki~8(t
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int everyPage, int totalPage, +S WtHj7e
int currentPage, int beginIndex){ Bg}l$?S
this.hasPrePage = hasPrePage; {< EPm&q
this.hasNextPage = hasNextPage; %y7ZcH'
this.everyPage = everyPage; 1Vc~Sa
this.totalPage = totalPage;
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this.currentPage = currentPage; q[9N4nj$<
this.beginIndex = beginIndex; &xZSM,
} E#,\[<pc
: ^U>n{
/** kP'm$+1or
* @return Xppv
* Returns the beginIndex. } =Xlac_U
*/ 97~>gFU77#
publicint getBeginIndex(){ QN|=/c<U
return beginIndex; 'Lw8l `7
} d]:G#<.
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/** sPVE_n
* @param beginIndex RAnF=1[v
* The beginIndex to set. 6}VFob#h8
*/ bYZU}Kl;(
publicvoid setBeginIndex(int beginIndex){ kKjcW` [
this.beginIndex = beginIndex; g*`xEb='
} sT "q]
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/** \
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* @return ;)wk^W
* Returns the currentPage. B?yjU[/R
*/ ALcPbr
publicint getCurrentPage(){ pw5{=bD
return currentPage; cx ("F/Jm
} |)C*i
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/** 2i;ox*SfpU
* @param currentPage wOCAGEg
* The currentPage to set. L[A?W
*/ %n GjP^
publicvoid setCurrentPage(int currentPage){ 8e^u KYR<
this.currentPage = currentPage; $4~Z]-38#A
} 4T;<`{]
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/** vU5}E\Ny
* @return U]w"T{;@.)
* Returns the everyPage. )B)f`(SA"<
*/ 0xO*8aKT
publicint getEveryPage(){ 6/?onEL9_
return everyPage; <VQ)}HW;k
} k3nvML,bv
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/** A0U9,M
* @param everyPage Xx%<rsA>F
* The everyPage to set.
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*/ -ucgET`
publicvoid setEveryPage(int everyPage){ Kd58'$
this.everyPage = everyPage; B f]Bi~w<
} B /w&Lo
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/**
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* @return mo] l_'
* Returns the hasNextPage. B2P@9u|9
*/ tl\<:8pI"
publicboolean getHasNextPage(){ |FM*1Q[1
return hasNextPage; "}`)s_rt
} T_=WX_h $
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/** I[v`)T'_{
* @param hasNextPage \q4r/SbgW
* The hasNextPage to set. 1^E5VG1[
*/ YURMXbj
publicvoid setHasNextPage(boolean hasNextPage){ RLMn&j|?e
this.hasNextPage = hasNextPage; %lWOW2~R
} Iv*\8?07)
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/** `>`b;A4
* @return k4dC
* Returns the hasPrePage. 6h,!;`8O
*/ KXK5\#+L
publicboolean getHasPrePage(){ h=:/9O{H
return hasPrePage; 7>BfHb
} h]k$K
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/** %dg[ho
* @param hasPrePage J-,ocO
* The hasPrePage to set. t(-,mw
*/
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publicvoid setHasPrePage(boolean hasPrePage){ ],S {?!'1
this.hasPrePage = hasPrePage; #Gg^QJ*
} ktx| c19
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/** uW[[8+t|
* @return Returns the totalPage. S#y[_C?H
* =urGs`\
*/ Y.]$T8
publicint getTotalPage(){ C`ky=
return totalPage; 6`@J=Q?
} ?zm]KxIC
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/** +jwHYfAK)
* @param totalPage ,:A;4
* The totalPage to set. |&rCXfC
*/ Q]/%Y[%|
publicvoid setTotalPage(int totalPage){ jd-]q2fQ|
this.totalPage = totalPage; yvoz 3_!
} #xw*;hW<
&tAYF_}
} ~<n.5q%Z
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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 /z*Z+OT2
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个PageUtil,负责对Page对象进行构造: &~H ed_
java代码: V)>?[
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/*Created on 2005-4-14*/ <SI|)M,, 3
package org.flyware.util.page; gE#'Zv {7
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import org.apache.commons.logging.Log; PVBz~rG
import org.apache.commons.logging.LogFactory; yEI@^8]s
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/** \}?X5X>
* @author Joa LD}~]
* l\*9rs:!
*/ F^NK"<tW
publicclass PageUtil { $}gMJG
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privatestaticfinal Log logger = LogFactory.getLog /q]rA
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(PageUtil.class); ,
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/** MxIa,M<
* Use the origin page to create a new page akzGJ3g
* @param page Z,.Hz\y1D
* @param totalRecords nTEN&8Y>R
* @return Y"GNJtsL "
*/ 0
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publicstatic Page createPage(Page page, int tbd=A]B-
"0P`=n
totalRecords){ 9qB0F_xl
return createPage(page.getEveryPage(), }oRBQP^&K
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page.getCurrentPage(), totalRecords); |1~n<=`Z
} ~P1~:AT
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/** _s=H|#l
* the basic page utils not including exception 8Y?M:^f~
6st
handler Rqh5FzB>
* @param everyPage X g6ezlW
* @param currentPage y>P+"Z.K%}
* @param totalRecords <W"W13*j!
* @return page YA4 D?'
*/ o8bd L<
publicstatic Page createPage(int everyPage, int "?I#!t%'
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currentPage, int totalRecords){ bO=|utpk
everyPage = getEveryPage(everyPage); ;.A}c)b
currentPage = getCurrentPage(currentPage); ]%' AZ`8
int beginIndex = getBeginIndex(everyPage, A9$x8x*Lt
%=`JWLLG
currentPage); $F2Uv\7=
int totalPage = getTotalPage(everyPage, %;,fI'M
HC%Hbc~S_Q
totalRecords); P0m3IH)
boolean hasNextPage = hasNextPage(currentPage, }e?H(nZS7h
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totalPage); )/T[Cnx.Nc
boolean hasPrePage = hasPrePage(currentPage); Y}:~6`-jj
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returnnew Page(hasPrePage, hasNextPage, z0[XI 7KK
everyPage, totalPage, jx: IK
currentPage, UerbNz|
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H
beginIndex); 7*!7EBb
} qO#3{kW
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privatestaticint getEveryPage(int everyPage){ ~KBa-i%o
return everyPage == 0 ? 10 : everyPage; (%my:\>l
} Re$h6sh
x'GB#svi
privatestaticint getCurrentPage(int currentPage){ KGz Nj%
return currentPage == 0 ? 1 : currentPage; j/ 5
} ,i2-
AUnfhk@$
privatestaticint getBeginIndex(int everyPage, int j#l=%H
(bsx|8[
currentPage){ b6D;98p
return(currentPage - 1) * everyPage; VW-qQe
} hyI7X7Hy
Bn}woyJdx
privatestaticint getTotalPage(int everyPage, int d54iZ`
6 d-\+t8
totalRecords){ *_(X$qfoW
int totalPage = 0; wZqYtJ
YKyno?m
if(totalRecords % everyPage == 0) a3@E`Z
totalPage = totalRecords / everyPage; <DF3!r
else :gVUk\)
totalPage = totalRecords / everyPage + 1 ; K@JZ$
+jm,nM9
return totalPage; F B]Y~;(
} \TV
OUX7
*_
privatestaticboolean hasPrePage(int currentPage){ pgU[di
return currentPage == 1 ? false : true; }A)\bffH
} Pvxb6\G&d
A_xC@$1e<
privatestaticboolean hasNextPage(int currentPage, O0 'iq^g
.wfydu)3
int totalPage){ 7sot?gF
return currentPage == totalPage || totalPage == rB>ge]$.
HIg2y
0 ? false : true;
5ZCu6A
} BoD{fg
afm\Iv[*
~ao:9ynY
} YpZB-9Krf
vy<W4
iT]t`7R
fvu{(Tb
;%tFi
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。 #:K=zV\
=[B\50]
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 >F/^y O
tl#sCf!c
做法如下: p3s i\Fm!
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 (s};MdXIz
Oa|c ?|+
的信息,和一个结果集List: #;[G>-tC
java代码: Et=Pr+Q{c
X\^V{v^-
#]` uH{
/*Created on 2005-6-13*/ |]\zlH"w
package com.adt.bo; ?UnQ?F(+G<
dC=[o\
import java.util.List; `fv5U%
i|:!I)(lh
import org.flyware.util.page.Page; y|`-)fY
\"lz,bT
/** Sd7jd ?#9'
* @author Joa !KHgHKEW^
*/ ;ALWL~Xm
publicclass Result { .j}]J:{%
qng ~,m
private Page page; z^bS+0S5x!
E7Lqa
S
private List content; )[rVg/m
"@V yc6L
/** J1w;m/oV
* The default constructor 7=-Yxt
*/ $xO8?
public Result(){ zdN[Uc+1Bd
super(); 3?Pg
;
} lM-9 J?j
kx,.)qKk
/** fi?4!h
* The constructor using fields s.J4&2Q
* JP#S/kJ%3
* @param page '*J+mZt N
* @param content Gwd38
*/ \|=6<ZY:
public Result(Page page, List content){ ON2o^-%=
this.page = page; +x]/W|5
this.content = content; TgiZ
% G
} =AIts[!qd
\n<!
ld
/** *HoRYCL
* @return Returns the content. <)7aNW.
*/ JR!-1tnc
publicList getContent(){ }g bLWx'iG
return content; l5 9a3=q
} sN41Bz$q.
z; GQnAG@
/** VN`.*B|9[
* @return Returns the page. (/:m*x*6
*/ ucN'
zq
public Page getPage(){ 1 Pk+zBJ$
return page; z\ZnxZ@
} MK1\
dl4n-*h
/** ?eS;Yc
* @param content ~$J;yo~
* The content to set. VZ9 p "
*/ ng}C$d . I
public void setContent(List content){ pGs?Y81
this.content = content; [qc1
V%g
} {irc0gI
KqI:g*H'x7
/** /.]u%;%r[
* @param page Q yqOtRk
* The page to set. A8-[EBkK
*/ sOhn@*X
publicvoid setPage(Page page){ )7 57
this.page = page; 8T1`9ITl:
} N@d~gE&^
} XvI~"}
24J c`%7,=
]0UYxv%]
o`YBz~2
@2E52$zu
2. 编写业务逻辑接口,并实现它(UserManager, s#^0[ Rt
!)bZ.1o
UserManagerImpl) 5zK,(cF0-
java代码: ,p|Q/M^
D!.c??
wV )\M]@
/*Created on 2005-7-15*/ 71{Q#%5U~
package com.adt.service; L3b0e_8>R
[FBS|v#T
import net.sf.hibernate.HibernateException; #Th)^Is
Sr
\y1nt
import org.flyware.util.page.Page; qA>#;UTp
f1vD{M;
import com.adt.bo.Result; w[X-Q+7p(t
lC($@sC %
/** 0/v]YK.
* @author Joa h*R@ d
*/ }uma<b
publicinterface UserManager { (_ G>dP_
lie,A
public Result listUser(Page page)throws [xiqlb,8
D>|`+=1'0"
HibernateException; lTC0kh
(
v*xW.
} tK;xW
DQGrXMpV0
~u&gU1}
LK DfV
)#i@DHt=
java代码: =\lw.59
?z>J7 }w*=
X,G<D}
/*Created on 2005-7-15*/ '>
ib
K|
package com.adt.service.impl; Qyw@ r
]EKg)E
import java.util.List; <|l}@\iRX
KO" /
import net.sf.hibernate.HibernateException; loIb}8
D% j GK
import org.flyware.util.page.Page; Il
[~
import org.flyware.util.page.PageUtil; Xqw}O2QQ1
H$Kc~#=
import com.adt.bo.Result; :(]fC~G~
import com.adt.dao.UserDAO; t+a.,$U
import com.adt.exception.ObjectNotFoundException; + ,Krq 3P
import com.adt.service.UserManager; 0h A: =r
36Lkcda[
/** =p_*lC%N
* @author Joa "}v.>L<P
*/ ktrIi5B
publicclass UserManagerImpl implements UserManager { AJ%E.+@=r
R%KF/1;/
private UserDAO userDAO; V22z-$cb
xnMcxys~
/** ?JZ$M
* @param userDAO The userDAO to set. "r46Rfa
*/ k\[(;9sf.
publicvoid setUserDAO(UserDAO userDAO){ #_.JkY
this.userDAO = userDAO; yMWh#[phH
} BP9#}{kE
cTGd<
/* (non-Javadoc) 41<~_+-@
* @see com.adt.service.UserManager#listUser =sk[I0W
$A?9U}V#^
(org.flyware.util.page.Page) Rq}lW.<r
*/ \'Ae,q|w
public Result listUser(Page page)throws 8GP17j
'yPKQ/y$x
HibernateException, ObjectNotFoundException { _CHzwNU
int totalRecords = userDAO.getUserCount(); @?<[//1
if(totalRecords == 0) e4` L8
throw new ObjectNotFoundException =|-=4.b+|
n/skDx TE
("userNotExist"); x.-d)]a!
page = PageUtil.createPage(page, totalRecords); K ~mUO
List users = userDAO.getUserByPage(page); K\2{SjL:B
returnnew Result(page, users); K#+?oFo:
} l$/pp
Sy VGm@
} 1_TuA(
i3,.E]/wX@
tq59w
83c2y;|8
,*iA38d.!
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 hiS|&5#
H<Sf0>OA
询,接下来编写UserDAO的代码: `sKyvPtG
3. UserDAO 和 UserDAOImpl: e>z"{ u(F0
java代码: F(hPF6Zx(
:$"{-n
elR'e6Q
/*Created on 2005-7-15*/ S[K5ofV
package com.adt.dao; w5 . ^meU
w~u{"E$
import java.util.List; <}J!_$A
=#u4^%i)
import org.flyware.util.page.Page; :gV~L3YW5
\!\:p/f
import net.sf.hibernate.HibernateException; Y ]([K.I=
s-IE}I?;
/** R@K\
* @author Joa x/O;8^b
*/ #tR:W?!
publicinterface UserDAO extends BaseDAO { tQ9%rb
4"2%mx:
publicList getUserByName(String name)throws Be|! S_Y P
Gk~aTO
HibernateException;
=c@hE'{
ya&=UoI
publicint getUserCount()throws HibernateException; st)is4
sa8O<Ab
publicList getUserByPage(Page page)throws P7-k!p"
ATkd# k%S
HibernateException; {P6Bfh7CZ
%"f85VfZ
} H7'42J@
0i\>(o
@_C]5D^J^~
rT `sY
+DRt2a#
java代码: lf`ULY4{
7"Xy8]i{z
~Fb@E0 }!
/*Created on 2005-7-15*/ =CFjG)L
package com.adt.dao.impl; Gt*<Awn8
0G8@UJv6
import java.util.List; N 8[rWJ#
c= t4 gf
import org.flyware.util.page.Page; iOZ9A~Ywy
~+' f[!^
import net.sf.hibernate.HibernateException; h^(U:M=A
import net.sf.hibernate.Query; (LK@w9)i;
7;p/S#P:
import com.adt.dao.UserDAO; h>bjG
F qJ`d2E
/** Yuv=<V
* @author Joa qVh?%c1.Y
*/ dlo`](5m
public class UserDAOImpl extends BaseDAOHibernateImpl +}m`$B}mJ
|$/#,Dv7
implements UserDAO { f1:>H.m`
FZgf"XM>
/* (non-Javadoc) B-LV/WJ_
* @see com.adt.dao.UserDAO#getUserByName )$p36dWl
U)'YR$2<
(java.lang.String) 0dwD ?GG2
*/ }uMu8)Q
publicList getUserByName(String name)throws }N9PV/a
jkl dr@t
HibernateException { s[7$%|~W
String querySentence = "FROM user in class s>L-0vG
Uhvy2}w
com.adt.po.User WHERE user.name=:name"; }'vQUGu8z
Query query = getSession().createQuery z@UH[>^gj
IgJG,!>h
(querySentence); #.u&2eyqQ
query.setParameter("name", name); i+S%e,U*
return query.list(); jA^yUd-
} V+y|C[A
F
bo/U5p
/* (non-Javadoc) al Rz@N
* @see com.adt.dao.UserDAO#getUserCount() 0<uL0FOT
*/ [|$C2Dhw=
publicint getUserCount()throws HibernateException { Gmu[UI}w8
int count = 0; Zah<e6L
String querySentence = "SELECT count(*) FROM [GCaRk>b,
L|{v kkBo
user in class com.adt.po.User"; O\q6T7bfRW
Query query = getSession().createQuery ~rrl"a>
>G1]#'6;
(querySentence); YO.ddy*59
count = ((Integer)query.iterate().next ymrnu-p o
kb$Yc)+R4
()).intValue(); ~Q^.7.-T
return count; V,Bol(wY
} yEB#*}K?
\1?'JdN
/* (non-Javadoc) 8fQfu'LyjY
* @see com.adt.dao.UserDAO#getUserByPage c;KMox/
tw 3zw`o:
(org.flyware.util.page.Page) LCXWpUj~
*/ BC#`S&R
publicList getUserByPage(Page page)throws <QgpePyoN
|U'` Sc
HibernateException {
^0{t
String querySentence = "FROM user in class >}Mw"
e~he#o[%a
com.adt.po.User"; #$ka.Pj
Query query = getSession().createQuery ( ?e
Et&
f\hQ>MLzt
(querySentence); a$iDn_{
query.setFirstResult(page.getBeginIndex()) ]#S<]v A
.setMaxResults(page.getEveryPage()); d=\TC'd"{
return query.list(); iu0'[
} Y HgNL LZ?
J}-e9vK-#
} Z" l].\=
F
FBrh!vQ<
;xFB
/,
\,m*CYs`
r0OP !u
至此,一个完整的分页程序完成。前台的只需要调用 TQ~a5q
0e:j=kd)NH
userManager.listUser(page)即可得到一个Page对象和结果集对象 0<<ATw$aQ
Te3 ?z
的综合体,而传入的参数page对象则可以由前台传入,如果用 [k%u$
%LqT>HXJ
webwork,甚至可以直接在配置文件中指定。 P~&J@8)c
44k8IYC*o
下面给出一个webwork调用示例: rNm_w>bq
java代码: 2h@&yW2j
Q4L7{^[X
EIpz-"S
/*Created on 2005-6-17*/ x*X{*?5@
package com.adt.action.user; fG8^ |:
8F$]@0v`%
import java.util.List; t3v_o4`&
xMpgXB!'
import org.apache.commons.logging.Log; 9B>P Qbs
import org.apache.commons.logging.LogFactory; {EVy.F
import org.flyware.util.page.Page; 8wkt9:
^%\MOjSN
import com.adt.bo.Result;
w%oa={x
import com.adt.service.UserService; Lv)1
)'v0
import com.opensymphony.xwork.Action; tp"eXA0n
qjg Z
/** &:}WfY!hX
* @author Joa XrXW6s;Z
*/ qJ~fEX
publicclass ListUser implementsAction{ F{
C2%
s#
!@arPN$
privatestaticfinal Log logger = LogFactory.getLog `O%O[
JZ>
(h
(ListUser.class); va"bw!zXo*
3".#nN
private UserService userService; S`TQWWQo;
X<v1ES$
private Page page; G2sj<F=AV
/*"pylm
privateList users; Vkf{dHjW
I;UT;/E2
/* _ib
@<%
* (non-Javadoc) : Hu{MN\
* ZhC,nbM
* @see com.opensymphony.xwork.Action#execute() Q/h-Khmz
*/ :FmH=pI!=
publicString execute()throwsException{ &xt
GabNk
Result result = userService.listUser(page); E},zB*5TH
page = result.getPage(); ;Z`R!
users = result.getContent(); ##alzC
return SUCCESS; /wP2Wnq$
} V:+z 3)qF
fILvEf4b
/** :"@-Bcln
* @return Returns the page. 7 Z?
Hyv
*/ W|s";EAM
public Page getPage(){ pEW~zl
return page; ovi^bNQ
} &$l#0?Kc^
mGkQx
-|
/** {9^p3Q+:P
* @return Returns the users. P^<to(|
*/ ~sq@^<M)s
publicList getUsers(){ GY^;$ ?
return users; T{yJL<
} :l?mNm5
'6*9pG-
/** | :id/
* @param page k*Aee7
* The page to set. pmO0/ty
*/ `82Dm!V
publicvoid setPage(Page page){ qL[SwEc
this.page = page; 'G>9 iw
} v53|)]V
tE-g]y3
/** ?zbW z=nq
* @param users >[~7fxjK-
* The users to set. -8<vW e
*/ rUAt`ykTmN
publicvoid setUsers(List users){ 25@@-2h @
this.users = users; DVJn;X^T:
} vJV/3-yX
:F@goiuC
/** 18Ju]U
* @param userService 5}Xi`'g,
* The userService to set. i$<")q
*/ m4Ue)
publicvoid setUserService(UserService userService){
ARs]qUY
this.userService = userService; ,LxkdV
} j-DWz>x
} ='m%Iq7X
?)(-_N&T
%H,s~IU
PL3hrI 5
Jyr
V2Tk^
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, I3d}DpPx%
lBAu@M
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 a6 0rJ#GD
het<#3Bo
么只需要: R^P>yk8
java代码: As`=K$^Il.
4l68+
Id>4fF:o
<?xml version="1.0"?> Ym!e}`A\F
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork zNdkwj p+
4v3gpLH
1.0//EN" "http://www.opensymphony.com/xwork/xwork- %'Q2c'r
ela^L_N hF
1.0.dtd"> G -+!h4p
i1-%#YYF(
<xwork> CH
29kQ
K7K/P{@9[9
<package name="user" extends="webwork- o[fg:/5)A
P)J-'2{
interceptors"> hqmE]hwc
X;Sb^c"j1
<!-- The default interceptor stack name hpPacN
+A)>
zx
--> f5FEHyj|
<default-interceptor-ref ^2+Vt=*
Fb=uN
name="myDefaultWebStack"/> El;"7Qn
kLZVTVSJt
<action name="listUser" T,1qR:58
@z{SDM
class="com.adt.action.user.ListUser"> $D#h, `
<param nReld
:#T
=CZRX'
+yN
name="page.everyPage">10</param> 31a lQ\TH
<result /#H P;>!n
dS4z Oz"
name="success">/user/user_list.jsp</result> #~"IlBk\
</action> VN!nef
orH6R8P]
</package> ?X@[ibH6
XGH:'^o_
</xwork> 9&AO
7Y(Dg`8G
5)lcgvp
e&d$kUJrq
9n{Y6I
x:
0#!}s&j/
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 c&',#.9
3WGE T[3
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。 ^Z?m)qxvB
jgIG";:Q
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 e8^/S^ =&d
AG=PbY9
&l1t5 !
"5~?`5Ff
`@],J
我写的一个用于分页的类,用了泛型了,hoho RBn/7
IONo&~-l
java代码: =CK% Zo
}%/mPbd#
@tm2Y%Y!
package com.intokr.util; *m+FMyr
`D~oY=
import java.util.List; %"A8Af**I
)__sw
/** SefhOh^,V
* 用于分页的类<br> =JzzrM|V*
* 可以用于传递查询的结果也可以用于传送查询的参数<br> w+
!c9
* -(:T&rfTp
* @version 0.01 K?'m#}]
* @author cheng Za|iU`e\
*/ <1*.:CL"s
public class Paginator<E> { mB_?N $K
privateint count = 0; // 总记录数 +?U[362>
privateint p = 1; // 页编号 IeYNTk&<
privateint num = 20; // 每页的记录数 N'ER!=l)
privateList<E> results = null; // 结果 Z%3CmKdeF
}vZf&ib-
/** [S,$E6&j$"
* 结果总数 5tbCx!tL
*/ {L7Pha
publicint getCount(){ ~Yk^(hl2
return count; %"mI["{
} )
~=pt&+
w gS'/
publicvoid setCount(int count){ $\J5l$tU
this.count = count; yl~;!
} ^t4^gcoZ4Z
e7;7TrB.
/** 3oLF^^^g
* 本结果所在的页码,从1开始 S}JOS}\^j
* P-4$Qksx
* @return Returns the pageNo. O00;0w u
*/ Ct)58f2
publicint getP(){ t/Io.d
return p; \KhcNr?ja=
} yR>P
xcW\U^1d
/** 5HOl~E
* if(p<=0) p=1 d9S/_iCI
* hE(R[hc
* @param p rt*x[5<
*/ rah"\f2
publicvoid setP(int p){ t~o"x .
if(p <= 0) f5 bq)Pm&
p = 1; ~
q-Z-MA
this.p = p; `YqtI/-w
} t7-]OY7%w_
<Tgy$Hm
/** =_-u;w1D
* 每页记录数量 #b;?:.m\=
*/ 3!p`5hJd
publicint getNum(){ vz4(
k/
return num; >ZOlSLu
} >S:(BJMo
O
ixqou
/** G"FO%3&|
* if(num<1) num=1 ~NK $rHwi%
*/ M5WB.L[@q
publicvoid setNum(int num){ fU|v[
if(num < 1) 6ncwa<q5
num = 1; s*Qyd{"z
this.num = num; ly`
A,dh
} bfA>kn0C
b+qd'
,.Z
/** 9 o,`peH
* 获得总页数 _\\Al v.
*/ UPGUJ>2Z
publicint getPageNum(){ pSlc (M>
return(count - 1) / num + 1; &qg6^&
} f9K7^qwkiz
e7GYz7
/** P{A})t7
* 获得本页的开始编号,为 (p-1)*num+1 A*DN/lG
*/ phH@{mI
publicint getStart(){ r&8aB85
return(p - 1) * num + 1; ,1~zYL?
} kV1L.Xg
J*rYw5QB
/** 5.VPK 338A
* @return Returns the results. Y!xPmL^]?
*/ W|8VE,"7
publicList<E> getResults(){ a,oTU\m
C
return results; Dazm8_x
} Sa<(F[p`
TQck$&
public void setResults(List<E> results){ ;j1
SSHZ
this.results = results; ^Saf
z8-3o
} m"~ddqSMT
H]tD~KM<
public String toString(){ |j0_^:2r=
StringBuilder buff = new StringBuilder 01o<eZ,
e;XRH<LhAU
(); =,zB|sjn
buff.append("{"); Mbxl{M
>
buff.append("count:").append(count); hiVa\s
buff.append(",p:").append(p); T9$~tv,5F
buff.append(",nump:").append(num); `l]Lvk8O
buff.append(",results:").append pZS]i
"
A<|9</9z
(results); /b>xQ.G
buff.append("}"); GkU_01C
return buff.toString(); 'sIne>
} 7u;N/@
K@=u F1?
} ied1+H
Ydrh+
'sZGLgT;m