Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 FxX nX
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 H//,qxDc
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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 `LWb L*;Y0
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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 \FIOFbwe
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分页支持类: 1i|5ii*vc
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java代码: =co6.Il
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package com.javaeye.common.util; wo ) lkovd
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import java.util.List; U$IB_a2
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publicclass PaginationSupport { #|} EPD9$
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publicfinalstaticint PAGESIZE = 30; Kx,<-]4
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privateint pageSize = PAGESIZE; bO gVCg
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privateList items; R?kyJ4S
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privateint totalCount; #$-`+P
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privateint[] indexes = newint[0]; iC<qWq|S_m
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privateint startIndex = 0; vj<JjGP
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public PaginationSupport(List items, int WNV}@
, *Z!Bd8
totalCount){ <3bFt [
setPageSize(PAGESIZE); ca$K)=cDW
setTotalCount(totalCount); A!`Q[%$
setItems(items); h Qbz}x
setStartIndex(0); *h"7!g
} K!SFS
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public PaginationSupport(List items, int NB)22 %
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totalCount, int startIndex){ ,S=ur%
setPageSize(PAGESIZE); MvlqxJ$
setTotalCount(totalCount); oei2$uu
setItems(items); #;>v,Jo
setStartIndex(startIndex); ]KRw[}z
} 2xpI|+a%
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public PaginationSupport(List items, int HY7#z2L
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totalCount, int pageSize, int startIndex){ WQYw@M~4Q!
setPageSize(pageSize); e[L%M:e9U
setTotalCount(totalCount); #uH%J<U
setItems(items); (wZ/I(4
setStartIndex(startIndex); S8)6@ECC
} Jm*wlN
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publicList getItems(){ b*"%E,?
return items; +T]D\];D
} X?OH//co
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publicvoid setItems(List items){ .L}k-8
this.items = items; 5g;i{T/6~x
} |]x>|Z?/u
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publicint getPageSize(){ qgw)SuwW
return pageSize; >Y"Ru#Ju9
} Dt*/tVF
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publicvoid setPageSize(int pageSize){ GC^>oF
this.pageSize = pageSize; <Is~DjIav
} di]TS9&9
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publicint getTotalCount(){ rE$=~s
return totalCount; ~k'SP(6#C
} p;9"0rj,z
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publicvoid setTotalCount(int totalCount){ NuC+iC$_/
if(totalCount > 0){ 4jdP3Q/
this.totalCount = totalCount; BBlYy5x
int count = totalCount / ^;a~_9
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pageSize; K)F6TvWv
if(totalCount % pageSize > 0) Z+G/==%3#,
count++; S;I}:F#5
indexes = newint[count]; e4(E!;Z!QF
for(int i = 0; i < count; i++){ ZA6)@Mn
indexes = pageSize * MPD<MaW$
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} >K-S&Y
}else{ QNm8`1
this.totalCount = 0; j)b[7%
} gano>W0
} fu $<*Sa2
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publicint[] getIndexes(){ TnQ"c)ta
return indexes; |kh7F0';"
} 0 pPSg9
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publicvoid setIndexes(int[] indexes){ ?_nbaFQK3
this.indexes = indexes; :SvgXMY@
} z6;6 o!ej
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publicint getStartIndex(){ g=]VQ;{
return startIndex; VH7nyqEM
} ![9umsx
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publicvoid setStartIndex(int startIndex){ ?]PE!7H
if(totalCount <= 0) ?n(OH~@$i
this.startIndex = 0; S>V+IKW;(
elseif(startIndex >= totalCount) I> BGp4 AQ
this.startIndex = indexes .6[7D
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[indexes.length - 1]; VHqHG`}:
elseif(startIndex < 0) /Xk-xg+U
this.startIndex = 0; 25{-GaB
else{
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this.startIndex = indexes a(oa?OdJ
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[startIndex / pageSize]; uJ
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} @p ZjJ<9QM
} ZGj ^,? a
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publicint getNextIndex(){ < wi9
int nextIndex = getStartIndex() + )J{.z
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pageSize; '|^x[8^
if(nextIndex >= totalCount) BnUWg ^E
return getStartIndex(); W!t =9i
else ble[@VW|
return nextIndex; +FJ+,|i
} y7~y@ 2
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publicint getPreviousIndex(){ +^|_vq^XR
int previousIndex = getStartIndex() - Lv
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pageSize; %8{nuq+c
if(previousIndex < 0) wl7 (|\-
return0; ApNS0
else 3t9Weo)
return previousIndex; <\ EJ:
} ~sT1J|
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} B;e (5y-
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抽象业务类 Dl@Jj?zc
java代码: `br$kB
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/** 55Y a(E
* Created on 2005-7-12 7z q@T]
*/ Kv9Z.DY
package com.javaeye.common.business; 6GA+xr=
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import java.io.Serializable; f~ wgMp.W0
import java.util.List; f0&%
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import org.hibernate.Criteria; ZeLed[J^xJ
import org.hibernate.HibernateException; ,49Z/P
import org.hibernate.Session; bEm9hFvd
import org.hibernate.criterion.DetachedCriteria; 8PR\a!"
import org.hibernate.criterion.Projections; L3=5tuQ[5
import Qk72ra)
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org.springframework.orm.hibernate3.HibernateCallback; C),i#v
import Z+=M_{`{
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org.springframework.orm.hibernate3.support.HibernateDaoS slzB#
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upport; <*(^QOM
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import com.javaeye.common.util.PaginationSupport; 6n^@Ps
RdBIbm
public abstract class AbstractManager extends u4j"U6"]M
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HibernateDaoSupport { )2a)$qx;
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privateboolean cacheQueries = false; aW-6$=W
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privateString queryCacheRegion; 0SDnMij&bf
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publicvoid setCacheQueries(boolean
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cacheQueries){ hd6O+i
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this.cacheQueries = cacheQueries; ?lML+
} %&S9~E
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publicvoid setQueryCacheRegion(String !Au#j^5K-o
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queryCacheRegion){ /,`OF/%
this.queryCacheRegion = WdH/^QvTP
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queryCacheRegion; K)U[xS;<
} inip/&P?V
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publicvoid save(finalObject entity){ M*f]d`B
getHibernateTemplate().save(entity); P?S]Q19Q4
} 5vg="@O K
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publicvoid persist(finalObject entity){ tva=DS
getHibernateTemplate().save(entity); NBHpM}1xtU
} C~R
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publicvoid update(finalObject entity){ FgL892[
getHibernateTemplate().update(entity); 7i!Vg V
} !I.}[9N
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publicvoid delete(finalObject entity){ Nte$cTjX
getHibernateTemplate().delete(entity); 9z..LD(
} ES?*w@x
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publicObject load(finalClass entity, _ OC@J*4.
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finalSerializable id){ ^Kg n:l
return getHibernateTemplate().load fjOq@thD
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(entity, id); xJ2I@*DN
} a|"Uw
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publicObject get(finalClass entity, k%FA:ms|k
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finalSerializable id){ n}j6gN! O
return getHibernateTemplate().get 9!
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(entity, id); ZXGi> E
} QW$p{ zo
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publicList findAll(finalClass entity){ !1fZ7a
return getHibernateTemplate().find("from ),-gy~
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" + entity.getName()); Mx$&{.LFJ
} Xh>($ U
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publicList findByNamedQuery(finalString }Uwji
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namedQuery){ vj]>X4'i
return getHibernateTemplate g(WP
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().findByNamedQuery(namedQuery); 4A6Yl6\Y
} 3TH?7wi
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publicList findByNamedQuery(finalString query, .z.4E:Iq
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finalObject parameter){ CF2Bd:mfZ
return getHibernateTemplate :Ys~Lt54
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().findByNamedQuery(query, parameter); }&t>j[
} !7
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publicList findByNamedQuery(finalString query, ,_fz)@)
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finalObject[] parameters){ KGHSEZi]
return getHibernateTemplate Vh;zV Y
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().findByNamedQuery(query, parameters); qfyZda0d
} |7tD&9<
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publicList find(finalString query){ o[T+/Ej&
return getHibernateTemplate().find !6T"J!F#
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(query); C=/B\G/.9
} XS [L-NHG
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publicList find(finalString query, finalObject j
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parameter){ N);w~)MYh
return getHibernateTemplate().find wOl?(w=|
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(query, parameter); )&Oc7\J,
} \ph.c*c
u]};QR
public PaginationSupport findPageByCriteria q8?kBKP
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(final DetachedCriteria detachedCriteria){ n%s%i-[5B
return findPageByCriteria !qj[$x-ns
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); La;G S
} Aw |;C
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public PaginationSupport findPageByCriteria [d6!
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(final DetachedCriteria detachedCriteria, finalint jC9us>b
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startIndex){ .h7s.p?
return findPageByCriteria g[3LPKQ
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(detachedCriteria, PaginationSupport.PAGESIZE, ~ELMLwn.
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startIndex); sQvRupYRO
} :oP LluW*
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public PaginationSupport findPageByCriteria tcuwGs>_
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(final DetachedCriteria detachedCriteria, finalint bf"'xn9
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pageSize, mm-s?+&M;
finalint startIndex){ ZgP%sF
return(PaginationSupport) uZS :
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getHibernateTemplate().execute(new HibernateCallback(){ -{cHp
publicObject doInHibernate i2~uhGJ
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(Session session)throws HibernateException { (+>
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Criteria criteria = [1VA`:?W
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detachedCriteria.getExecutableCriteria(session); elOeXYO0
int totalCount = G%<}TI1}
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((Integer) criteria.setProjection(Projections.rowCount N{;!xIv
;sZG=y@
()).uniqueResult()).intValue(); s[yWBew
criteria.setProjection Cbw *?9d
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(null); fu/8r%:h
List items = hmO2s/~
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criteria.setFirstResult(startIndex).setMaxResults =
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C82_)@96
(pageSize).list(); `@~e<s`j
PaginationSupport ps = Y'iX
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new PaginationSupport(items, totalCount, pageSize, XA>W>|
<v_=k],W
startIndex); =ejj@c
return ps; 8M,*w6P
} eqo0{e
}, true); !eLj +0
} ;c(a)_1
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public List findAllByCriteria(final 9y7N}T6
J D\tt-
DetachedCriteria detachedCriteria){ tE7jTe
return(List) getHibernateTemplate m&UP@hUV-
z M9#1^X
().execute(new HibernateCallback(){ =)[m[@,c
publicObject doInHibernate =q4}(
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(Session session)throws HibernateException { Kc MzY
Criteria criteria = 9u B?-.
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detachedCriteria.getExecutableCriteria(session); e
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return criteria.list(); [XfR`@
} U
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}, true); ?[D3-4
} F "@% 7xy
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public int getCountByCriteria(final -aoYoJ '
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DetachedCriteria detachedCriteria){ [{znwK@
Integer count = (Integer) iNO>'7s7
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getHibernateTemplate().execute(new HibernateCallback(){ _C?j\Wy
publicObject doInHibernate jEc_!Q
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(Session session)throws HibernateException { K:PH:e
Criteria criteria = TlqHj
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detachedCriteria.getExecutableCriteria(session); ^|]&"OaB
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return BQ@7^E[
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criteria.setProjection(Projections.rowCount \iuR+I
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()).uniqueResult(); 7aG.?Ca%
} tcD7OC:"6
}, true); DJP6Z
return count.intValue(); ,T/Gv;wa2
} N'Gq9A
} XHr*Rs.[=
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用户在web层构造查询条件detachedCriteria,和可选的 ]g_VPx"
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 P*|N)S)X%
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PaginationSupport的实例ps。 A~zn;
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ps.getItems()得到已分页好的结果集 ,+=9Rp`md
ps.getIndexes()得到分页索引的数组 }V?m
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ps.getTotalCount()得到总结果数 %b6$N_M{H1
ps.getStartIndex()当前分页索引 _:x]'w%
ps.getNextIndex()下一页索引 {15j'Qwm
ps.getPreviousIndex()上一页索引 vgfC{]v<W]
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 OgQdyU
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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 L*@`i ]jl
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一下代码重构了。 t^s&1#iC
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我把原本我的做法也提供出来供大家讨论吧: _y@28t
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首先,为了实现分页查询,我封装了一个Page类: ]\E"oZ
java代码: lZFu|(
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/*Created on 2005-4-14*/ ClG%zE&i
package org.flyware.util.page; 2qMiX|Y
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/** ~#_~DqbMZ5
* @author Joa :@A&HkF
* Y
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*/ /K=OsMl2b8
publicclass Page { u4x-GObJM
2d)Dhxzxk
/** imply if the page has previous page */ L%'J]HL-
privateboolean hasPrePage; ?
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/** imply if the page has next page */ AdX))xgl
privateboolean hasNextPage; tOwn M1
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/** the number of every page */ iaGA9l<b
privateint everyPage; bI):-2&s}
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{
/** the total page number */ mF4W4~"
privateint totalPage; 5ggyk0
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/** the number of current page */ cslC+e/
privateint currentPage; *?)MJ@
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/** the begin index of the records by the current 1d^~KBfv
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query */ uEPp%&D.+
privateint beginIndex; u$ts>Q;5
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/** The default constructor */ ]OAU&t{
public Page(){ o9kJ90{D=
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} H.5
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/** construct the page by everyPage uGU2
* @param everyPage 0.MB;gm:
* */ <)qa{,GX\
public Page(int everyPage){ <=(K'eqC^
this.everyPage = everyPage;
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} L+t
/
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/** The whole constructor */ }$ y.qqG
public Page(boolean hasPrePage, boolean hasNextPage, G[64qhTC
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int everyPage, int totalPage, vYgJu-Sl
int currentPage, int beginIndex){ Z{8%Cln
this.hasPrePage = hasPrePage; HQ-[k$d
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this.hasNextPage = hasNextPage; wL;OQhI
this.everyPage = everyPage; l@`k:?
this.totalPage = totalPage; d i\.*7l?
this.currentPage = currentPage; }7PJr/IuF
this.beginIndex = beginIndex; ;,y_^-h;
} ,Ag {-&
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/** Q2CGC+
* @return d59rq<yI
* Returns the beginIndex. K1
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*/ R
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publicint getBeginIndex(){ GT6; I7
return beginIndex; n:AZ(f
} ib,`0=0= O
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/** u`ir(JIj]
* @param beginIndex $z=a+t *
* The beginIndex to set. ~d*Q{v~3
*/ AD;m[u7
publicvoid setBeginIndex(int beginIndex){ :Drf]D(sMX
this.beginIndex = beginIndex; P~7(x7/7~
} lMv6QL\>'
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/** vfSPgUB)
* @return ,='Ihi
* Returns the currentPage. z~{08M7
*/ _L,~WYRo
publicint getCurrentPage(){ MN: {,#d0
return currentPage; #}Qe{4L
} /_{-~0Z=@B
Df"PNUwA"
/** w1Bkz\95
* @param currentPage rCJ$Pl9R
* The currentPage to set. *`a$6F7m4
*/ tP_.-//
publicvoid setCurrentPage(int currentPage){ r] /Ej!|
this.currentPage = currentPage; f2.=1)u.
} 2Z; !N37U
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/** 2)EqqX[D
* @return :7{GOx
* Returns the everyPage. |5>Tf6$(
*/ g?
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publicint getEveryPage(){ jV%
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return everyPage; 4s{=/,f
} F=\
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/** `.@udfog^0
* @param everyPage &Wy>t8DIK
* The everyPage to set. B9(w^l$kZ|
*/ #(
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publicvoid setEveryPage(int everyPage){ @tT`s^e
this.everyPage = everyPage; O%%Q./oh
} $uLTYu
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/** 6{I7=.V
* @return &D<6Go/)_*
* Returns the hasNextPage. >p&"X 2
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*/ &5}YTKe}|
publicboolean getHasNextPage(){ JCH9~n.
return hasNextPage; UV(`.
} x@X2r
h<L_ =)lH
/** a>C;HO
* @param hasNextPage :@(1~Hm
* The hasNextPage to set. 6TRLHL~B
*/ 2UQF:R?LQ
publicvoid setHasNextPage(boolean hasNextPage){ Zx8$M5
this.hasNextPage = hasNextPage; OX,em Ti
} %C%3c4+Oh
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/** H~*N:$C
* @return F=5+JjrX
* Returns the hasPrePage. )]n>.ZmLCB
*/ g Cp`J(2v:
publicboolean getHasPrePage(){
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return hasPrePage; KXZG42w
} LYAGpcG
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/** Cuylozj$&
* @param hasPrePage Dx\~#$S!=
* The hasPrePage to set. f0eQq;D$K
*/ PE.UNo>o
publicvoid setHasPrePage(boolean hasPrePage){ tOXyle~C
this.hasPrePage = hasPrePage; Ew4D';&;
} rvx2{1}I
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/** wsdZwik
* @return Returns the totalPage. 5NkF_&S_1
* eP (*.
*/ q AVypP?J
publicint getTotalPage(){ |>P:R4P
return totalPage; [`|t( E'
} /#5rt&q
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/** hxdjmc-
* @param totalPage kM-8%a2i
* The totalPage to set. vEjf|-Mb9
*/ $Ptl&0MN%
publicvoid setTotalPage(int totalPage){ {pQ8/Af!
this.totalPage = totalPage; /.s
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} UV|{za$&/
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} 6r^ZMW
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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 ,1~B7Zd
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个PageUtil,负责对Page对象进行构造: TlO=dLR7d
java代码: Obu 6k[BE.
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/*Created on 2005-4-14*/ nUs=PD3)
package org.flyware.util.page;
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import org.apache.commons.logging.Log; [4EIy"
import org.apache.commons.logging.LogFactory; Cm5L99Y
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/** S^q^=q0F
* @author Joa m
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* "cS7E5-|
*/ 0^L:`[W+
publicclass PageUtil { |0^IX
V6>{k_0{V
privatestaticfinal Log logger = LogFactory.getLog `?^<r%*F.
zgS)j9q}
(PageUtil.class); ys)
8/B8yY-O
/** qi^kf
* Use the origin page to create a new page 3f>9tUWhTy
* @param page 8bw,dBN
* @param totalRecords zn'Mi:O'p
* @return '?90e4x3/
*/ y)fz\wk
publicstatic Page createPage(Page page, int )(d~A?~
N f?\O@
totalRecords){ 2/ )~$0
return createPage(page.getEveryPage(), 6ImW|%
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page.getCurrentPage(), totalRecords); JFu.o8[Q
} &~<i"
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/** lib^JJF
* the basic page utils not including exception (w_b
! qtj1.w
handler /2r&ga&
* @param everyPage )MV `'i
* @param currentPage 79Aa~ +i'_
* @param totalRecords e2xKo1?I
* @return page .|:(VG$MfI
*/ ~hP]<$v
publicstatic Page createPage(int everyPage, int <,*w$
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currentPage, int totalRecords){ V[8!ymi0
everyPage = getEveryPage(everyPage); .K_50%s
currentPage = getCurrentPage(currentPage); Y3V2}
int beginIndex = getBeginIndex(everyPage, dF|n)+C~R
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currentPage); >0 := <RW
int totalPage = getTotalPage(everyPage, |+-b#Sa9
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totalRecords); JBV
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boolean hasNextPage = hasNextPage(currentPage, G]-\$>5R
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totalPage); I_c?Ky8J_|
boolean hasPrePage = hasPrePage(currentPage); Q>z(!'dw
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returnnew Page(hasPrePage, hasNextPage, wO%617Av
everyPage, totalPage, v&])D/a
currentPage, '\pSUp
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beginIndex); n>o=RQ2
} AAi4}
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privatestaticint getEveryPage(int everyPage){ =m;cy0))
return everyPage == 0 ? 10 : everyPage; (^ J2(
} 5M%)*.Y
3[
REOWSs$'
privatestaticint getCurrentPage(int currentPage){ Sfi1bsK
return currentPage == 0 ? 1 : currentPage; ![[:Z
} P$__c{1\
Vvn~G.&)
privatestaticint getBeginIndex(int everyPage, int <P5 7s+JK
I0bkc3
currentPage){
" v'%M({
return(currentPage - 1) * everyPage; Z1\=d =
} <?rdhx
*Xu?(Jd
privatestaticint getTotalPage(int everyPage, int =`qEwA
) C#>@W
totalRecords){ R|\kk?,u
int totalPage = 0; OQ3IkE`G
b\SB
if(totalRecords % everyPage == 0) o^d
totalPage = totalRecords / everyPage; m7cG]a~a
else fo;^Jg.
totalPage = totalRecords / everyPage + 1 ; m.yt?`
,_'Z Jlx
return totalPage; @
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} ~. 5[
n}J!?zZc
privatestaticboolean hasPrePage(int currentPage){ ur+ \!y7^R
return currentPage == 1 ? false : true; Z(ToemF)hi
} <@c9S,@t
Jb!s#g
privatestaticboolean hasNextPage(int currentPage, ;k=`J
1:Raa 5
int totalPage){ ZyrVv\'
return currentPage == totalPage || totalPage == ]%(X}]}
_10I0Z0
0 ? false : true; |Mnc0Fgvy,
} w!l*!G
%G,d&%f
0[-@<w ^j
} `9DW}
cw;TIx_q
\`?4PQ
|zp}u (N
@(m?j1!M
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。 <[z9*Tm
6 Znt
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
{u$<-W-&
l Ztw[c
做法如下: _W BWFGj
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0w".o!2\U{
{G-y7y+E
的信息,和一个结果集List: iB*1Yy0DC
java代码: tIW~Ng
i7O8f^|
Mir(
}E
/*Created on 2005-6-13*/ <OGXKv@
package com.adt.bo; XNkZ^3mq
.#Lu/w' -M
import java.util.List; B|kIiL63
D
VBg
M7d
import org.flyware.util.page.Page; r4pR[G._
&bwI7cO
/** eq4Yc*|9
* @author Joa M^y5 Dep
*/ 6M6r&,yRu
publicclass Result { \x~},!l
)VkH':yCM
private Page page; bx3kd+J7
$_u)~O4$
private List content; kXZG<?
}\.Z{h:t
?
/** ga|-~~
* The default constructor K]>X31Ho
*/ kIH)>euZ
public Result(){ ByW,YKMy
super(); k mX:~KMb
} tZN'OoZ
Wo/LrCg
/** 5NhwIu^<
* The constructor using fields '+\.&'A
* }N#hg>;
B
* @param page QzD8
jk#
* @param content 'z x1kq1
*/ q=/ck
public Result(Page page, List content){ O.'\GM
this.page = page; HAGpM\Qa
this.content = content; X/<Q3AK
} B&z~}lL
e-YMFJtoK}
/** 2PEA<{u
* @return Returns the content. ^}<h_T?<_-
*/ l'#a2Pl
publicList getContent(){ )C#b83
return content; 1|H(q
} j<'ZO)q`Q
Bpdx]5qfK
/** !WQ S.&
* @return Returns the page. uzaDK
*/ f/%QMhM:
public Page getPage(){ nCdxn#|
return page; Nr0}*8#j
} oz/Nx{bg
q,2 +\i
/** eGlPi|
* @param content dW"=/UW
* The content to set. 3W"l}.&ZJ"
*/ 6e At`L[K.
public void setContent(List content){ :eW`El
this.content = content; .#}`r`/
} S2"H E`
vUgMfy&
/** J4q_}^/2w
* @param page fV5MI[t
* The page to set. sB%QqFRP
*/ }:4b_-&Q5
publicvoid setPage(Page page){ NekPl/4
this.page = page; |E9iG
} -gy@sSfvkv
} K_CE.8G&{
iCh,7I,m
6@geakq
^z}$'<D9
&bT \4
2. 编写业务逻辑接口,并实现它(UserManager, J(=io_\bO
<%:,{u6
UserManagerImpl) S3.76&
java代码: \"?5CHz*
Z-rHYfa4
TAKvE=a;
/*Created on 2005-7-15*/ hScC<=W
package com.adt.service; .{
r
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@_C?M5v
import net.sf.hibernate.HibernateException; }J|Pd3Q Sf
I&|J +B?#
import org.flyware.util.page.Page; y:ad%,. C
b]xE^zM-I`
import com.adt.bo.Result; /zZ";4
O}mz@-Z
/** 7':qx}c#!1
* @author Joa kr>H,%3~
*/ pF}WMt
publicinterface UserManager { zJX _EO
db0]D\
public Result listUser(Page page)throws ])H[>.?K
VJ()sbl{k
HibernateException; &BS*C} },
rM{V>s:N
} {<y.G1<.
GR>kxYM%q
Hw
1cc3!
We?cRb
g]E>e v{`
java代码: CH+mzy
GLE"[!s]f
K *xca(6
/*Created on 2005-7-15*/ ,7mB`0j>
package com.adt.service.impl; \9`76*X6
c
V"DilV$v
import java.util.List; 0m
7_#g4$L
qpXsQim$~
import net.sf.hibernate.HibernateException; R.$1aqA}
8(|lP58~
import org.flyware.util.page.Page; JJVdq-k+`
import org.flyware.util.page.PageUtil; PiZU_~A
RA$q{$arb
import com.adt.bo.Result; VFLW@
import com.adt.dao.UserDAO; \ICc?8oL
import com.adt.exception.ObjectNotFoundException; mVNHH!
import com.adt.service.UserManager; )H|cri~D
j$Wd[Ja+O
/** lmpBf{~ S
* @author Joa 9HBRWh6
*/ $v0beN6MG
publicclass UserManagerImpl implements UserManager { <%GfF![v
>dYN@cB$}
private UserDAO userDAO; y';"tD Fb
} za"rU
/** c=#V*<
* @param userDAO The userDAO to set. :oO
?A
*/ "1|\V.>>;
publicvoid setUserDAO(UserDAO userDAO){ O"V;otlC
this.userDAO = userDAO; E2u9>m4_J
} 1yV+~)by3
pUD(5v*0R
/* (non-Javadoc) f S-PM3
* @see com.adt.service.UserManager#listUser iM(Q-%HP_
r%412#
(org.flyware.util.page.Page) ViYfK7Z
*/ Vh'H =J
public Result listUser(Page page)throws SBh"^q
U2vM|7]VP
HibernateException, ObjectNotFoundException { ,Aw
Z%
int totalRecords = userDAO.getUserCount(); RAB'%CY4
if(totalRecords == 0) p4^&G/'
throw new ObjectNotFoundException `Y_G*b.Rm
8Ai\T_l
("userNotExist"); 7-A/2/G<
page = PageUtil.createPage(page, totalRecords); S?<hs,
List users = userDAO.getUserByPage(page); fOJTy0jX8
returnnew Result(page, users); v$~$_K
} eI3ZV^_Ps
rBUWzpE"
} z=yE- I{
O
8XHaVLg3
*~0U4kw+
7Xf52\7n
@RXkj-,eC#
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 b!oj3|9
9|NH5A"H.
询,接下来编写UserDAO的代码: ?4cj"i
3. UserDAO 和 UserDAOImpl: bZW dd6
java代码: |qz&d=>
{@ Z=b5/P
oe<DP7e
/*Created on 2005-7-15*/ 8e32NJ^k~
package com.adt.dao; X+kgx!u'y
2Og<e|
import java.util.List; kwUy^"O
zEk/15
import org.flyware.util.page.Page; SW)jDy
A~({vb'
import net.sf.hibernate.HibernateException; ;(&S1Rv9
i "d&U7Q
/** t W}"PKv
* @author Joa ;cfPS
*/ <S3s==Cg
publicinterface UserDAO extends BaseDAO { &a.A8v)
Z -fiJ75
publicList getUserByName(String name)throws (\UpJlW
Y49&EQ
HibernateException; lc\{47LwZ
aM+Am,n`@
publicint getUserCount()throws HibernateException; B
*%ey?
)kD B*(?
publicList getUserByPage(Page page)throws nrg$V>pD
2p~}<B
HibernateException; OJiwI)a9
lokKjs
} 9DdR"r'7
nh*6`5yj
ksf6O$
ZI.Czzx\=
*vzEfmN:d
java代码: }0,dG4Oo=
N}>[To3
2Q 5-.2]
/*Created on 2005-7-15*/ 8]D0)
package com.adt.dao.impl; P^AI*tH"m
1gQ_76Yck
import java.util.List; #I1q,fm
>t{-_4Yv?
import org.flyware.util.page.Page; #>6Jsnv1
X0Wx\xDg[
import net.sf.hibernate.HibernateException; +ZOKfX
import net.sf.hibernate.Query; dhjX[7Bl9
SY.ZEJcv
import com.adt.dao.UserDAO; <nTZs`$LwL
zx5#eMD
/** |DYgc$2pN
* @author Joa vi28u xc
*/ +)LCYDRV7
public class UserDAOImpl extends BaseDAOHibernateImpl Xdf4%/Op
hn~btu9h
implements UserDAO { N\|BaZ%>|
ST2:&xH(
/* (non-Javadoc) OG9 '[o`8
* @see com.adt.dao.UserDAO#getUserByName !yd]~t
5Q
(D:-p:q.
(java.lang.String) 6j!idA!'
*/ udXzsY9Ng
publicList getUserByName(String name)throws D?=4'"@v
EJ(36h
HibernateException {
T%Bz >K
String querySentence = "FROM user in class .yDGw Lry
/b\c<'3NY
com.adt.po.User WHERE user.name=:name"; `~z[Hj=2
Query query = getSession().createQuery zhJ0to[%?
(%OZ `?`
(querySentence); "j&'R#$&d
query.setParameter("name", name); Zrp-Hv27,,
return query.list(); wJD'q\n
} \~g,;>%7Y
#m17cDL
/* (non-Javadoc) {Kf5a
m
* @see com.adt.dao.UserDAO#getUserCount() A{e>7Z72
*/ w3z'ZCcr;"
publicint getUserCount()throws HibernateException { ':3[?d1Es
int count = 0; ik#Wlz`4
String querySentence = "SELECT count(*) FROM `5e{ec
c7
3-&~jm~"
user in class com.adt.po.User"; p8 Ao{
Query query = getSession().createQuery g)R 2V
N6v?Qzvi
(querySentence); cg o
count = ((Integer)query.iterate().next &>B"/z
8Ihl}aguW
()).intValue(); jZC[_p;
return count; IJt'[&D
} +xvn n
;6~5FTmV
/* (non-Javadoc) Eh)VT{vp
* @see com.adt.dao.UserDAO#getUserByPage l4dG=x}M]
Oi zj|'
(org.flyware.util.page.Page) z1]nC]2
*/ ;rF[y7\
publicList getUserByPage(Page page)throws r<4j;"lQK
C BoCT3@~
HibernateException { PXqG;o*Q*?
String querySentence = "FROM user in class jFJ}sX9]
<_ENC>NP
com.adt.po.User"; shw"TF>?zG
Query query = getSession().createQuery N.H<'Q8&
/&<V5?1|
(querySentence); !/!ga)Y
query.setFirstResult(page.getBeginIndex()) _6V1oe2
.setMaxResults(page.getEveryPage()); zhm 0J-g
return query.list(); d^J)Mhju
} % P Ex
EZN!3y| m
} g8l6bh$}
H%X F~tF:
l?
U!rFRq`
E3l*_b0
":vEWp+g
至此,一个完整的分页程序完成。前台的只需要调用 7RWgc]@?>
1]eRragm"
userManager.listUser(page)即可得到一个Page对象和结果集对象 k|\M(Z*(P
V.z8
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的综合体,而传入的参数page对象则可以由前台传入,如果用 wMj#.Jh
]ly" K!1,
webwork,甚至可以直接在配置文件中指定。 GGhk~H4OP
2aX*|DGpw
下面给出一个webwork调用示例: f*B-aj#
java代码: yi*EobP
A= 5Ebu!z
R^$|D)(
/*Created on 2005-6-17*/ aZCq{7Xs
package com.adt.action.user; vy*-"=J
jS~Pdz
import java.util.List; IhBc/.&RL
(S?Y3l|
import org.apache.commons.logging.Log; QxdC[t$Lp
import org.apache.commons.logging.LogFactory; w3ni@'X8
import org.flyware.util.page.Page; CUYA:R<)
q:TNf\/o
import com.adt.bo.Result; 4k-Ak6s
import com.adt.service.UserService; $\Y&2&1s
import com.opensymphony.xwork.Action; pITF%J@_]
xE
w\'tH
/** Pv/v=s>X
* @author Joa XWnP(C9?
*/ w$6Z}M1d
publicclass ListUser implementsAction{ 4$[o; t>
CDRbYO
privatestaticfinal Log logger = LogFactory.getLog {\(MMTQ
@$T$ hMl
(ListUser.class); `vgaX,F*
[GI~ &
private UserService userService; sqtz^K ROM
U]~@_j
private Page page; Tk4>Jb
Lr D@QBT
privateList users; j}eb
_K+I
%z-*C'j5H
/* HyU: BW;
* (non-Javadoc) rO$pj~!|Q
* ?nGi if
* @see com.opensymphony.xwork.Action#execute() NFZ(*v1U
*/ j*G: 8Lg
publicString execute()throwsException{ robg1
Result result = userService.listUser(page); 0^gY4qx[u
page = result.getPage(); 1wKXOy=v0
users = result.getContent(); ^]nLE]M
return SUCCESS; ^ls@Gr7`P
} v62_VT2v
Ze eV-
/** 0H}tb}4
* @return Returns the page. JiaR*3#
*/ #~|k EGt
public Page getPage(){ P,{Q k~iu
return page; PY.K_(D
} hOUH1m.
>8"Svt$
/** |(z{)yWbC[
* @return Returns the users. b4e~Z
*/ %- 540V{q
publicList getUsers(){ *y?HaU
return users; q2vD)r
} 1N8] ~j
UxTLr-db^
/** !S':G
* @param page k.ou$mIY
* The page to set. V|97;
*/ C~qZ&
publicvoid setPage(Page page){ nc k/Dw
this.page = page; 1@}F8&EZ
} <|}Z6Ti
`Npa/Q
/** THp_ dTD
* @param users n[iwi
* The users to set. WMf /
S"=
*/ Ayw_LCUD
publicvoid setUsers(List users){ (XO=W+<'
this.users = users; ;\mX=S|a
} )=[\Yf K
T(D6'm:X
/** @(sz "
* @param userService <eG| `
* The userService to set. 1_]X
*/ A*y4<'}<
publicvoid setUserService(UserService userService){ 2d[q5p
this.userService = userService; L/tpT?$fi
} ?$f.[;mh
} N>H@vt~
3U@jw,K!{A
)[Tm[o?Y.
^Spu/55_
F?Lt-a+
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, 6VGY4j}:(
:2?g_
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 #KJ# 1
'v6@5t19j
么只需要: (u@:PiU/eP
java代码: aj&L
Z DD6
q`c!!Lg
xaMDec V
<?xml version="1.0"?> I@cw=_EQL
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork el9P@r0
mAW.p=;
1.0//EN" "http://www.opensymphony.com/xwork/xwork- r N$0qo
g-sNYd%?a
1.0.dtd"> F/s
n"2
w \b+OW
<xwork> wXQxZuk[
~S8:xG+s
<package name="user" extends="webwork- oe*1jR_J`[
@|b-X? `
interceptors"> eP-|3$
|UXSUP
@s
<!-- The default interceptor stack name ks#3
o+
)UKX\nD"0
--> y8k8Hd1<f
<default-interceptor-ref 7}X1A!1
%10ONe}
name="myDefaultWebStack"/> }nd>SK4
BDI|z/~&
<action name="listUser" [H}>
2Q
{<,%_pJR
class="com.adt.action.user.ListUser"> HOP*QX8C%
<param g<j)
Z =+Z96
name="page.everyPage">10</param> "2cOS PpQL
<result FH,]'
$tmdE)"&
name="success">/user/user_list.jsp</result> 7iP+!e}$.
</action> cRT'?w`}
&i5@4,p y9
</package> >w
S'z]T9
S<0 &V
</xwork> bJ^h{]
i>Q!5
;'7(gAE
V`I4"}M1
7}kJp%-
! ?g+'OM
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 ix!xLm9\
m/=nz.
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。 A=N$5ZJ
+RooU?Aq
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 lFzVd
N
=1IK"BA2?
}DhqzKl
sW]_Ky.]
m;@q('O
我写的一个用于分页的类,用了泛型了,hoho :PO./IBX
=
lo.LFV
java代码: 6("_}9ZOc
?:"ABkL|+Y
6
VEB2F
package com.intokr.util; n28JWkK8
[dJ!JT/X{
import java.util.List; ALMsF2H
o2!738
/** T9nb ~P[
* 用于分页的类<br> ?
:H+j6+f
* 可以用于传递查询的结果也可以用于传送查询的参数<br> S{=5nR9 j
* /WN YS
* @version 0.01 `_\KN_-%Vu
* @author cheng I C
*/ [HILK`@@
public class Paginator<E> { b>-DX
privateint count = 0; // 总记录数 n~^SwOt~;5
privateint p = 1; // 页编号 pfN(Ae
Pt
privateint num = 20; // 每页的记录数 QG5WsuT
privateList<E> results = null; // 结果 <*(Z}p
Kip&YB%rk
/** %f]#P8VP
* 结果总数 y[_k/.1
*/ (]]hSkE
publicint getCount(){ !xsfhLZK
return count; oIhKMQ;jh
} ?bZH Aed
?NMk|+
publicvoid setCount(int count){ 0m_yW$w
this.count = count; )3h\QE!z
} sYKx3[ V/
AQ,lLn+
/** NqD]p{>Y
* 本结果所在的页码,从1开始 PT/Nz+
* I6.rN\%b
* @return Returns the pageNo. UoT`/.
*/ :HY$x
publicint getP(){ JS/'0.
return p; fL*7u\m:
} N5?bflY
^k6_j\5j
/** 1:-'euA"
* if(p<=0) p=1 yv,FzF}7
* \=%lH =yS
* @param p z!}E2j_9P
*/ 6
U.Jaai:
publicvoid setP(int p){ a4*v'Xc5
if(p <= 0) ` Ig5*X4|
p = 1; FV^jCseZ
this.p = p; 6`e{l+c=F
} 7]VR)VA M
)9eIo&Nl
/**
)-2Nc7
* 每页记录数量 C~En0 G1
*/ CS[]T9|_
publicint getNum(){
{++EX2
return num; a/J<(sak~X
} :c*"Dx'D
2-4N)q
/** Bu:%trlgV
* if(num<1) num=1 Ln>!4i+-B)
*/ -@> {q/
publicvoid setNum(int num){ i2<z"v63
if(num < 1) u&zY>'}zm
num = 1;
x=*Y|
this.num = num; !ku}vTe
} 'kd}vq#|
63fYX"
/**
)@wC6Ij
* 获得总页数 e;.,x 5+
*/ X$kLBG[o_
publicint getPageNum(){ ~~>m
return(count - 1) / num + 1; !5*VBE\
} b<W\#3~G
JQQyl: =
/** F.vRs|fk
* 获得本页的开始编号,为 (p-1)*num+1 3&-rOc
*/ $ f:uBhM
publicint getStart(){ o5Oig
return(p - 1) * num + 1; -E7mt`:d
} K6v~!iiK$
I5"wa:Z
/** ^+(5[z
* @return Returns the results. Q>1BOH1by
*/ Z=Y29V8
publicList<E> getResults(){ <nk|Z'G E
return results; Nc+0_|,
} >G`p T#
hUMG}<
public void setResults(List<E> results){ C*Q7@+&
this.results = results; :C5w5
Vnj
} !Rv ;~f/2
5IU!BQU
public String toString(){ //@6w;P
StringBuilder buff = new StringBuilder 0+\725DJ
gPMR,TU
(); S`-I-VS=L
buff.append("{"); #BRIp(65-6
buff.append("count:").append(count); O=Su
E/q
buff.append(",p:").append(p); kQ+y9@=/g
buff.append(",nump:").append(num); PZ]tl
buff.append(",results:").append J^+w]2`S
F,_L}
(results); f`qy~M&
buff.append("}"); -zK>{)Z=q
return buff.toString(); D.Ke
} ~n
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I0
t#{i
} HI5NWdfRl
uda++^y:
Cd'D
~'=