Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Gn;eh~uw;l
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 -b(:kAwStk
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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 "aP>}5<h
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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 @}x)>tqD
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分页支持类: ;oULtQ
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java代码: @^;WC+\0
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package com.javaeye.common.util; (1(3:)@S6
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import java.util.List; \J-O b
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publicclass PaginationSupport { pp#Kb 2*
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publicfinalstaticint PAGESIZE = 30; ygUvO3Z
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privateint pageSize = PAGESIZE; :
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privateList items; oRy?Dx+H
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privateint totalCount; =}r&>|rrJ
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privateint[] indexes = newint[0]; ss,t[`AV{
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privateint startIndex = 0; #JO#PV%
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public PaginationSupport(List items, int }.2pR*W
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totalCount){ xv7^
setPageSize(PAGESIZE); YIfPE{,
setTotalCount(totalCount); $|6Le;
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setItems(items); cdP+X'Y4D
setStartIndex(0); \(Zdd
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} Si*Pi
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public PaginationSupport(List items, int .m/Lon E
0'BR Sa<
totalCount, int startIndex){ MJV&%E6{:{
setPageSize(PAGESIZE); 7x-k-F3
setTotalCount(totalCount); N iNZh;
setItems(items); J%f5NSSU{6
setStartIndex(startIndex); _ZzPy;[i?
} `W?aq]4x5
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public PaginationSupport(List items, int >|@ /GpD
):LJ {.0R
totalCount, int pageSize, int startIndex){ IDE@{Dy
setPageSize(pageSize); UH%?{>oRh
setTotalCount(totalCount); Cl<`uW3
setItems(items); q'+XTal
setStartIndex(startIndex); Wz:MPdz3(
} k%NY,(:(
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publicList getItems(){ StP6G ]x
return items; fBD5K3
} yql+N[
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publicvoid setItems(List items){ :
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this.items = items; A+Y>1-=JO
} I g-VSQ
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publicint getPageSize(){ ;n7k_K#0z!
return pageSize; F2oY_mA
} &E {/s
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publicvoid setPageSize(int pageSize){ i]hFiX
this.pageSize = pageSize; g6QkF41nG
} Gu*;z% b2
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publicint getTotalCount(){ nsw.\(#
return totalCount; 79:x>i=
} JZu7Fb]L9
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publicvoid setTotalCount(int totalCount){ a_QO)
if(totalCount > 0){ w|?Nq?KA
this.totalCount = totalCount; NqhRJa63
int count = totalCount / R\0]\JEc
1ZhJ?PI,9{
pageSize; :$/lGIz
if(totalCount % pageSize > 0) ;13lu1
count++; Ha)w*1&w"
indexes = newint[count]; |;rjr_I
for(int i = 0; i < count; i++){ $Xz9xzOR
indexes = pageSize * kc~Z1
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i; L\y,7@1%AT
} HX+'{zm]
}else{ SRM[IU
this.totalCount = 0; _u{D #mmO
} 2lAuO!%
} I9SO}a2p
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publicint[] getIndexes(){ uZmfvMr3
return indexes; w{2V7*+l
} e
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publicvoid setIndexes(int[] indexes){ ':o.vQdJ
this.indexes = indexes; #0G9{./C
} 1vl~[
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publicint getStartIndex(){ Y/gVyQ(
return startIndex; 1mI)xDi9
} w4(DR?[nC
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publicvoid setStartIndex(int startIndex){ ,@Ed)Zoh
if(totalCount <= 0) )_xM)mH
this.startIndex = 0; qZ_^#%zO
elseif(startIndex >= totalCount) 0lmoI4bW}s
this.startIndex = indexes YfxZ<
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[indexes.length - 1]; 7OC,KgJ3
elseif(startIndex < 0) bB)EJCPq>
this.startIndex = 0; O_F<VV*MFQ
else{ `Ph4!-6#
this.startIndex = indexes aWe
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[startIndex / pageSize]; /wCP(1Mw
} nfrC@Av
} C@]Z&H;
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publicint getNextIndex(){ ut-UTW
int nextIndex = getStartIndex() + gyI5;il~
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pageSize; 4^AE;= Q
if(nextIndex >= totalCount) "=yaeEp
return getStartIndex(); O%0G37h
else ,p$1n;
return nextIndex; >K50 h
} !^l<jrM
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publicint getPreviousIndex(){ z${B|
int previousIndex = getStartIndex() - |!57Z4X
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pageSize; )2bPu[U
if(previousIndex < 0) '7xmj:.==
return0; s`H}NjWx
else dxMz!
return previousIndex; ~73YOGiGJH
} P_&2HA,I
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} 6wnfAli.
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抽象业务类 !u\ X,.h
java代码: n~K_|
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/** zJdlHa{
* Created on 2005-7-12 / x$O6gi
*/ D_@r_^}
package com.javaeye.common.business; q'K=Ly+
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import java.io.Serializable; 5<ery~q
import java.util.List; _4.`$n/Z
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import org.hibernate.Criteria; W J^r~*r
import org.hibernate.HibernateException; B[cZEFo\
import org.hibernate.Session; 61!R-
import org.hibernate.criterion.DetachedCriteria; }ZvL%4jT
import org.hibernate.criterion.Projections; 0%'&s)#
import ^(UL$cQ>
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org.springframework.orm.hibernate3.HibernateCallback; 6AZ/whn#
import Pfi '+I`s
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org.springframework.orm.hibernate3.support.HibernateDaoS 1{nXmtvr
Y}nE/bmx&9
upport; eCk}B$ 2
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import com.javaeye.common.util.PaginationSupport; iSIj ?.
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public abstract class AbstractManager extends e-{k;V7b
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HibernateDaoSupport { @uT\.W:Q2
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privateboolean cacheQueries = false; 193Q
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privateString queryCacheRegion; 10}\7p8
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publicvoid setCacheQueries(boolean aSKI%<?xN
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cacheQueries){ Jqjb@'i
this.cacheQueries = cacheQueries; j<wg>O:s%r
} ` [@
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publicvoid setQueryCacheRegion(String d;;]+%
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queryCacheRegion){ rf]]I#C7
this.queryCacheRegion = oD~VK,.
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queryCacheRegion; ho fZpM
} 9:YiLoz?
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publicvoid save(finalObject entity){ p~+)!Z#
getHibernateTemplate().save(entity); p0'A\@|
} XP6R$0yN
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publicvoid persist(finalObject entity){ l_+s$c
getHibernateTemplate().save(entity); ddlLS
} eNN% %Q
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publicvoid update(finalObject entity){ M<g>z6
getHibernateTemplate().update(entity); +a"Asvw2
} .T4"+FTzP
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publicvoid delete(finalObject entity){ 7(Y!w8q&^
getHibernateTemplate().delete(entity); %2bZeZ
} J/R=O>
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publicObject load(finalClass entity, S-'iOJ1]
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finalSerializable id){ />K$_T/]
return getHibernateTemplate().load &[qLl
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(entity, id); ]W-:-.prh
} Zpl?zI
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publicObject get(finalClass entity, [
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finalSerializable id){ 'UW7zL5
return getHibernateTemplate().get waO*CjxE:
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(entity, id); fLct!H3
} f=g/_R2$xN
ryN/sjQC
publicList findAll(finalClass entity){ u|O5ZV-cd
return getHibernateTemplate().find("from 2+
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d!e$BiC
" + entity.getName()); yxLGseD
} KzI$GU3
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publicList findByNamedQuery(finalString U#d",s
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namedQuery){ 7cY_=X-?Y
return getHibernateTemplate tezsoR!.ak
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().findByNamedQuery(namedQuery); 2vu"PeU9
} .2[>SI
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publicList findByNamedQuery(finalString query, YDC[s ^d5
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finalObject parameter){ K,?M5n '
return getHibernateTemplate mY#[D;mUe
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().findByNamedQuery(query, parameter); L?4c8!Q
} _"##p
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publicList findByNamedQuery(finalString query, !$qNugLg
@H1pPr
finalObject[] parameters){ jYO@ %bQ
return getHibernateTemplate o @~XX@5l
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().findByNamedQuery(query, parameters); F+*:
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} )Xl/|YD
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publicList find(finalString query){ y<8)mw
return getHibernateTemplate().find R%8nR6iG"
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(query); YJ.'Yc
} #B;` T[
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publicList find(finalString query, finalObject Yg<o 9x$
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parameter){ Rfeiv
return getHibernateTemplate().find fPZBm&`C
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(query, parameter); MU-ie*+
} Xr6lYO _R
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public PaginationSupport findPageByCriteria 'O
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(final DetachedCriteria detachedCriteria){ ~EpMO]I
return findPageByCriteria ^['% wA%
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ga+\b>C
} K3!|k(jt
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public PaginationSupport findPageByCriteria TM[Z~n(wt
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(final DetachedCriteria detachedCriteria, finalint #xm<|s
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startIndex){ D0us<9q
return findPageByCriteria =@G#c5H*
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(detachedCriteria, PaginationSupport.PAGESIZE, m:/ nw,
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startIndex); :-Ho5DHg
} J<>z}L{
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public PaginationSupport findPageByCriteria *{)[:;
DTlM}
(final DetachedCriteria detachedCriteria, finalint }8fxCW*|
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pageSize, `IFt;Ja\6
finalint startIndex){ v}+axu/?
return(PaginationSupport) :BC0f9
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getHibernateTemplate().execute(new HibernateCallback(){ QKE$>G
publicObject doInHibernate 9'Pyo`hJ#U
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(Session session)throws HibernateException { %0Ulh6g;Dt
Criteria criteria = Yw\}'7
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detachedCriteria.getExecutableCriteria(session); I&q:w\\z8|
int totalCount = *~lD;{2
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((Integer) criteria.setProjection(Projections.rowCount G>YJ3p7
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()).uniqueResult()).intValue(); ;6e#W!
criteria.setProjection )j',e$m
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(null); gTH1FR8$y
List items = 1AjsAi,7;2
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criteria.setFirstResult(startIndex).setMaxResults C ])Q#!D|
e ! 6SJ7xC
(pageSize).list(); dY;^JPT
PaginationSupport ps = `[jQn;
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new PaginationSupport(items, totalCount, pageSize, TEh]-x`
LCyci1\@
startIndex); \&&kUpI
return ps; 23_<u]V
} c^6v7wT5
}, true); e,Gv~ae9
} G"5Nj3vd
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public List findAllByCriteria(final Q2Yv8q_}Uq
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DetachedCriteria detachedCriteria){ -=Q_E^'
return(List) getHibernateTemplate y$r9Y!?s
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().execute(new HibernateCallback(){ l#\z3"b
publicObject doInHibernate !6@xX08z
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(Session session)throws HibernateException { rPaD#GA[7
Criteria criteria = 69dFd!G\
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detachedCriteria.getExecutableCriteria(session); E,c~.jYc
return criteria.list(); f8#WT$Ewy
} -E2[PW4$
}, true); J.$<Lnt>u
} 7. G
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public int getCountByCriteria(final /JEH%)
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DetachedCriteria detachedCriteria){ e&OMW,7
Integer count = (Integer) FT[oM<M\Xd
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getHibernateTemplate().execute(new HibernateCallback(){ 0k:&7(j
publicObject doInHibernate @E,{p"{
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(Session session)throws HibernateException { #_2V@F+,
Criteria criteria = $\81WsL'
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detachedCriteria.getExecutableCriteria(session); d%t]:41=Z
return ,h#!!j\j6
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criteria.setProjection(Projections.rowCount >u*woNw(XM
d=oOMXYa
()).uniqueResult(); I%e7:cs >
} ]N!SG@X+
}, true); 7Kk rfJqN
return count.intValue(); Kp~k!6x
} D4
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} :54|Z5h|
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用户在web层构造查询条件detachedCriteria,和可选的 g#9w5Q
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 nI2}E
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PaginationSupport的实例ps。 s.=)p"pTd
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ps.getItems()得到已分页好的结果集 :{_Or'L
ps.getIndexes()得到分页索引的数组 qE$.a[
ps.getTotalCount()得到总结果数 k5!k3yI
ps.getStartIndex()当前分页索引 e&;c^Z
ps.getNextIndex()下一页索引 +FY-r[_~
ps.getPreviousIndex()上一页索引 Pk8L-[&v
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 nz+o8L,
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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 R#Bt!RNZ
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一下代码重构了。 P%ZWm=lg
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我把原本我的做法也提供出来供大家讨论吧: ngeX+@
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首先,为了实现分页查询,我封装了一个Page类: T?AGQcG
java代码: Y1`.
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/*Created on 2005-4-14*/ Mh~T.;f.qq
package org.flyware.util.page; }[LK/@h
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/** `(Q58wR}
* @author Joa YQQ!1hw
* YgM6z K~
*/ +QldZba
publicclass Page { =;Wkg4\5
}-r"W7]k
/** imply if the page has previous page */ *k+QX
privateboolean hasPrePage; A:
0]
n
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/** imply if the page has next page */ u52;)"&=)
privateboolean hasNextPage; g-+p(Ll|
N..9N$+(
/** the number of every page */ ~Rv U+D
privateint everyPage; e% 5!
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/** the total page number */ Nz!AR$
privateint totalPage; f{3FoN=z
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/** the number of current page */ D"^ogY#LK
privateint currentPage; \GMudN
/23v]HEPy
/** the begin index of the records by the current ,pLesbI
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query */ jDXmre?
privateint beginIndex; 4?%0z) g
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/** The default constructor */ t:M>&r:BL
public Page(){ ~gBqkZ# y?
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} oK(ua
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/** construct the page by everyPage A)`M*(~
* @param everyPage ][?GJ"O+U
* */ Z<&:
W8n
public Page(int everyPage){ TzK?bbgr!
this.everyPage = everyPage; HH+rib'u
} >`oO(d}n[0
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/** The whole constructor */ ^'[ |
public Page(boolean hasPrePage, boolean hasNextPage, Q7}wY
VJ=!0v
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int everyPage, int totalPage, "4"L"lJ
int currentPage, int beginIndex){ R0/~)
P
this.hasPrePage = hasPrePage; ZT^PL3j+
this.hasNextPage = hasNextPage; [Xz7.<0#U
this.everyPage = everyPage; J41ZQ
this.totalPage = totalPage; 2l\Oufer"
this.currentPage = currentPage; S:1! )7
this.beginIndex = beginIndex; ,9A[o`b
} PMrvUM62
ko,
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/** v
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* @return {?m',sG;&
* Returns the beginIndex. 5@v!wms
*/ *S=v1 s/
publicint getBeginIndex(){ }'@*Ol j
return beginIndex; ~?L. n:wu
} i,)kI
w\@Anwj#L
/** ^3r2Q?d\
* @param beginIndex z ,ledTl
* The beginIndex to set. l|uN-{w
*/ MT&i5!Z
publicvoid setBeginIndex(int beginIndex){ ]I}'
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this.beginIndex = beginIndex; Zmp ^!|=X!
} h[lh01z
N86Hn]#
/** lq%s/l
* @return #[i({1`^L
* Returns the currentPage. xknP
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*/ =E,*8O]
publicint getCurrentPage(){ ,>~92
return currentPage; |bBYJ
} 2^:5aABQ
^$T>3@rDB
/** /#Xz+#SqY
* @param currentPage RWoa'lnu
* The currentPage to set. @0)bY*njj
*/ -bs~{
publicvoid setCurrentPage(int currentPage){ BGA.8qWR4
this.currentPage = currentPage; w>!KUT
} Q p<6qM35
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/** ,m:MI/)p
* @return {WC{T2:8
* Returns the everyPage. SYC_=X
*/ +1cK (Si
publicint getEveryPage(){ IPY@9+]
return everyPage; M<)HJ lr
} H>W A?4
p oNQ<ijK
/** l$zM|Z1wR`
* @param everyPage PVU(RJ
* The everyPage to set. {j^}"8GB
*/ bx5X8D
publicvoid setEveryPage(int everyPage){ (IEtjv}D
this.everyPage = everyPage; gMgbqGF)
} Y=Bk;%yT=
HZM&QZHx)`
/** 2>UyA.m0
* @return ,rG$JCS'KQ
* Returns the hasNextPage. (A?e}M^}
*/ T$RZRZo
publicboolean getHasNextPage(){ WAob"`8]
return hasNextPage; Ao=.=0os
} ^(a %B
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/** QRa>W/N
* @param hasNextPage sYp@.?Tz
* The hasNextPage to set. ya|7hz {
*/ e&wWlB![
publicvoid setHasNextPage(boolean hasNextPage){ v_oNM5w
this.hasNextPage = hasNextPage; z?+N3p9
} A!hkofQ
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/** :GO}G`jY
* @return ^OYar(
* Returns the hasPrePage. \f%jN1z
*/ eyUo67'7
publicboolean getHasPrePage(){ IF@)L>-%
return hasPrePage; Rb\\6BU0
} (u RAK
{HQ?
/** NPKRX Li%
* @param hasPrePage sH#UM(N
* The hasPrePage to set. Dmn6{jyP
*/ CB6<Vng}C
publicvoid setHasPrePage(boolean hasPrePage){ k+%6:r,r&
this.hasPrePage = hasPrePage; \/'u(|G
} *R8q)Q
qM]eK\q 1
/** up`!r;5-
* @return Returns the totalPage. {6A3?q
* &s\w:
9In
*/ #uFP
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publicint getTotalPage(){ rr2|xL?+u
return totalPage; H}X3nl\]
} M2mte#h
mVW:]|!s
/** V[Auw3)
* @param totalPage t&0pE(MO/
* The totalPage to set. 1_*o(HR
*/ fnwtD*``
publicvoid setTotalPage(int totalPage){ hcwKi
this.totalPage = totalPage; hQPiGIs
} b`fPP{mG
X>=`{JS1
} _KC()OIeC
\h?C
G_|]
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/J8y[aa
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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 ErHbc2
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个PageUtil,负责对Page对象进行构造: K`768%q
java代码: 9UZKL@KC
jL>IX`,+6
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/*Created on 2005-4-14*/ +P81&CaY
package org.flyware.util.page; Hh4$Qr;R
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import org.apache.commons.logging.Log; oaM $<
import org.apache.commons.logging.LogFactory; OT&J OTk\
hK&jo(V
/** 9v8{JaI3
* @author Joa TE3A(N'
* -y)ij``VY
*/ }RDGk+x7|
publicclass PageUtil { oxha8CF]D
r|:i: ii
privatestaticfinal Log logger = LogFactory.getLog kW3V"twx
#\_N-bVu
(PageUtil.class); a4Fe MCvV9
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/** k$j>_U? P
* Use the origin page to create a new page 6DD"Asi+
* @param page nM>oG'm[n
* @param totalRecords :]v%6i.
* @return sjvlnnO
*/ D
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publicstatic Page createPage(Page page, int |^[]Oy=
#;#
V1
totalRecords){ (:4N#p
return createPage(page.getEveryPage(), nm_]2z O
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page.getCurrentPage(), totalRecords); {m.l{<H
} aqSHo2]DX9
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/** w$MFCJ:p&
* the basic page utils not including exception YIvJN
oJA%t-&%R
handler PbvRh~n
* @param everyPage iC10|0%{
* @param currentPage ~Pq1@N>n
* @param totalRecords FctqE/>}I
* @return page J\^ZRu_K
*/
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publicstatic Page createPage(int everyPage, int CkKr@. dV
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currentPage, int totalRecords){ }(4U7Ac
everyPage = getEveryPage(everyPage); ]h3<r8D_#
currentPage = getCurrentPage(currentPage); S='AA_jnw
int beginIndex = getBeginIndex(everyPage, ^I*</w8
/g BB
currentPage); d!mtSOh
int totalPage = getTotalPage(everyPage, ms@*JCL!t
^V#9{)B
totalRecords); X`JWYb4
boolean hasNextPage = hasNextPage(currentPage, "7mYs)=
RB`Emp&T
totalPage); GVP"~I~/:
boolean hasPrePage = hasPrePage(currentPage); ]r8t^bqe
* $~H=4t
returnnew Page(hasPrePage, hasNextPage, N}HQvlLkF9
everyPage, totalPage, $w4%JBZr
currentPage, Cp` [0v~0
Vf9PHHH|
beginIndex); ,\laqH\ 1%
} \x P$m|Y3
N3nFE:`u]
privatestaticint getEveryPage(int everyPage){ mrX 2w
return everyPage == 0 ? 10 : everyPage; r2M Iw
} azF|L"-RP
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privatestaticint getCurrentPage(int currentPage){ >{?~cNO&
return currentPage == 0 ? 1 : currentPage; _H@Y%"ZHJ6
} 5N<f\W,
6;6a.iZ
privatestaticint getBeginIndex(int everyPage, int 3omFd#EP
7N9~nEU
currentPage){ #-*7<wN
return(currentPage - 1) * everyPage; sLrSi
} d$Y3 a^O|
RZ 4xR
privatestaticint getTotalPage(int everyPage, int {G$I|<MD2T
zO8`xrN!
totalRecords){ uTTM%-DMHT
int totalPage = 0; })RT2zw}
1henQiIO
if(totalRecords % everyPage == 0) >oSNKE
totalPage = totalRecords / everyPage; R1OC7q
else `]%\Y>(a}
totalPage = totalRecords / everyPage + 1 ; O_^O1
b~dm+5W7
return totalPage; mCOJ1}
} hiO:VA
A`_(L|~
privatestaticboolean hasPrePage(int currentPage){ kzU;24"K
return currentPage == 1 ? false : true; U'(}emh}
} /)fx(u#
Rj6:.KEJ
privatestaticboolean hasNextPage(int currentPage, GPlAQk
:?W {vV
int totalPage){ OjO$.ecT
return currentPage == totalPage || totalPage == v0hr ~1
64xq@_+
0 ? false : true; =+;1^sZ
} ^T*^L=L_(
x}Qet4vV
dJID '2a
} Xvu|ss
y
Nb&;E7 H
/xf4*zr
:a$ZYyD
/!J1}S
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。 vl59|W6
BM PLL2I
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 ZfalB
U U!M/QJ
做法如下: vQf'lEFk
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 FD>j\
Zkl:^!*
的信息,和一个结果集List: u=^0n2ez
java代码: ER,,K._?B
+W|MAJtg
8was/^9;
/*Created on 2005-6-13*/ $T* ##kyE9
package com.adt.bo; 0=Jf93D5
2_Me
4
import java.util.List; ^ei[#I
nTrfbK@
import org.flyware.util.page.Page; <qZ"W6&&
~@a7RiE@
/** @?ntMh6
* @author Joa E-h`lDoJ
*/ lsmzy_gV7
publicclass Result { R:=C
FkJa+ZA
private Page page; Kp,}7%hDw!
#k? Rl
private List content; _YF~DU
^pz3L'4n
/** T8Sgu6:*R
* The default constructor ,])@?TJb@
*/ J]uYXsC
public Result(){ 9D74/3b*
super(); ^aVoH/q*C
} 'G z>X :
%-"?
/** _i [.5
* The constructor using fields pAg;Rib
* *0bbSw1kc
* @param page "aNl2 T
* @param content `K[:<p}
*/ tm\ <w H
public Result(Page page, List content){ wqDRFZ1*P
this.page = page; g*8LdH6mq
this.content = content; b:fy
} qmUq9bV
]RHR> =;
/** PHRc*G{
* @return Returns the content. X'N4a
*/ <LM<,
publicList getContent(){ Zrfp4SlZZ
return content; U|odm 58s
} m'1NZV%#
#|^7{TN
/** 5r/QPJ<h
* @return Returns the page. cn ,zUG!-h
*/ =DTn9}u
public Page getPage(){ gOw|s1`2,
return page; ~D@pk>I
} )CS7>Vx
N^|r.J
/** U@[P.y~J
* @param content Y1AbG1n|
* The content to set. EK.L>3
*/ G[u_Uu=>
public void setContent(List content){ Q(m} Sr4
this.content = content; G 8|[.n
} AG)N^yd
[:$j<}UmB
/** "hz(A.THi
* @param page s<0yQ-=.?N
* The page to set. Vja' :i
*/ FVLXq0<Cj
publicvoid setPage(Page page){ L]0+u\(
this.page = page; IDBhhv3ak
} +AyQ4Q(-o
} M0o=bYI
Y%qhgzz?/
sBp|Lo
FsZM_0>/s
_J&u{
2. 编写业务逻辑接口,并实现它(UserManager, rPK?pJ
GN{\ccej
UserManagerImpl) )<4o"R:*
java代码: W"Dj+/uS
$V?zJ:a>L
T,(IdVlJ
/*Created on 2005-7-15*/ Rz`<E97-
package com.adt.service; 93fKv
`u:U{m
import net.sf.hibernate.HibernateException; dv4)fG]W;_
Jf`;F :
import org.flyware.util.page.Page; M4M
4*o
c}vy9m$B_
import com.adt.bo.Result; do*`-SDy
R#tz"T@
/** WlP@Tm5g/
* @author Joa 6 6x} |7
*/ LYh5f#
publicinterface UserManager { P;KbS~ SlC
F~a5yW:R=)
public Result listUser(Page page)throws O|,+@qtH
Fhn883
HibernateException; ?>q=Nf^ Q.
A4';((OXy
} V]H<:UE
23+6u{
mUr@w*kq|p
I>/`W
3~I<f^K4
java代码: e^~t52]
9b]*R.x:$&
~QBf78@Gf
/*Created on 2005-7-15*/ k;zbq
package com.adt.service.impl; 0x# 6L
b9|F>3?r>
import java.util.List; "+nURdicO
l=9&
import net.sf.hibernate.HibernateException; /G[y
24 Q
pRc(>P3;
import org.flyware.util.page.Page; WbH/K]/1)h
import org.flyware.util.page.PageUtil; !::k\}DS
IvIBf2D;Q
import com.adt.bo.Result; NL&g/4A[a
import com.adt.dao.UserDAO; l[G,sq"
import com.adt.exception.ObjectNotFoundException; |BH,
H
import com.adt.service.UserManager; k`)LO`))
M#S8x@U
/** pI(FUoP^
* @author Joa c'`7p/l.
*/ |nry^zb
publicclass UserManagerImpl implements UserManager { .[cT3l/t
.U5+PQN
private UserDAO userDAO; |&n dQ(!l
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/** O-T/H-J`
* @param userDAO The userDAO to set.
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*/ 9U}EVpD
publicvoid setUserDAO(UserDAO userDAO){ (-dJ0!
this.userDAO = userDAO; qwFn(pK[
} m$LZ3=v%8
W\~ZmA.
/* (non-Javadoc) "r"]NyM
* @see com.adt.service.UserManager#listUser /Z2*>7HM8[
qWE"vI22M
(org.flyware.util.page.Page) S"3g 1yU^_
*/ Z/-%Eb]L1
public Result listUser(Page page)throws \
vJ*3H6
vy|}\%*r~
HibernateException, ObjectNotFoundException { * y(2BrL>
int totalRecords = userDAO.getUserCount(); 6w1:3~a
if(totalRecords == 0) Kyl(
throw new ObjectNotFoundException dje3&a
) 0}o bPp
("userNotExist"); LiV]!*9$KG
page = PageUtil.createPage(page, totalRecords); b:O4d<+%
List users = userDAO.getUserByPage(page); <Isr
returnnew Result(page, users); y
Fp1@*ef
} Ds}6{']K
Wnf`Rf)1z
} |=%$7b\C
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t&r?O dc&m
|um)vlN;9
vN4X%^:(
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fs)O7x-B(
!Aw.f!
询,接下来编写UserDAO的代码: cuKgO{.GH
3. UserDAO 和 UserDAOImpl: $^
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java代码: V|a59[y?
9h0|^ttF
> %Y#(_~a
/*Created on 2005-7-15*/ nQ~q-=,L
package com.adt.dao; ;F0A\5I
.FMF0r>l
import java.util.List; D1g1"^~g
/ TJTu_#
import org.flyware.util.page.Page; \pPq]k
T2(+HI2
import net.sf.hibernate.HibernateException; ]iNSa{G
v#/,,)m
/** lJYv2EZ
* @author Joa \uPT-M*
*/ 6|jE3rHw
publicinterface UserDAO extends BaseDAO { 3t_5Xacj
&Y#9~$V=
publicList getUserByName(String name)throws HE,wEKp
6)bfd^JYn
HibernateException; s[s^z<4G
>=Rb:#UM
publicint getUserCount()throws HibernateException; jgMWjM6.
EhVnt#`Si
publicList getUserByPage(Page page)throws r}5GJ|p0
1Gqtd^*;
HibernateException; U)l>#gf8
/KV@Ce\
} dkn_`j\v
B " B
oNh .Zgg
R1m18GHQ
,}|V'y
java代码: ?<}qx`+%Q
.ZJh-cd
"1nd~
BBOw
/*Created on 2005-7-15*/ j68Gz5;j
package com.adt.dao.impl; hs*:!&E
{Y/
import java.util.List; < 1r.p<s
LaIif_fie^
import org.flyware.util.page.Page; ){(cRB $
Ud9\;Qse
import net.sf.hibernate.HibernateException; ]E3g8?L
import net.sf.hibernate.Query; AP~!YwLW
pKJ[e@E^
import com.adt.dao.UserDAO; SwL\=nq+~
(J;?eeP
/** 50Jr(OeU<
* @author Joa ujSzm=_P
*/ _HL3XT
public class UserDAOImpl extends BaseDAOHibernateImpl 'qD9kJ`
*K 7L5.
implements UserDAO { Zu hT \l
}hf*Jw
/* (non-Javadoc) G?g7G,|d
* @see com.adt.dao.UserDAO#getUserByName Z:OO|x
KWY G\#S0]
(java.lang.String) ^49moC-
*/ 8]L.E
publicList getUserByName(String name)throws R.QcXz?d
?t"PawBWE
HibernateException { 3HiW1*5W
String querySentence = "FROM user in class lt]U?VZ
QRjt.Ry|
com.adt.po.User WHERE user.name=:name"; INT2i8oU
Query query = getSession().createQuery zJy{Ry[Sb
GhT7:_r~
(querySentence); th<]L<BP/
query.setParameter("name", name); CNz[@6-cYU
return query.list(); ;wF|.^_2
} yUG5'<lX
$5o<Mj
/* (non-Javadoc) /l`XJs
* @see com.adt.dao.UserDAO#getUserCount() 5C&f-* Bh
*/ q8lK6p\:W
publicint getUserCount()throws HibernateException { utE:HD.PN
int count = 0; 5 6R,+sN
String querySentence = "SELECT count(*) FROM EpfmH `
S ] &->5"
user in class com.adt.po.User"; K|/a]I":
Query query = getSession().createQuery D^~gq`/)
{MtB!x
(querySentence); :}z%N7T
count = ((Integer)query.iterate().next 7AiCQWf9
V Y3{1Dlf
()).intValue(); Yp)U'8{h c
return count; w~&]gyf
} Ed-gYL^<
2I<T<hFW]
/* (non-Javadoc) mI0r,Z*+M
* @see com.adt.dao.UserDAO#getUserByPage MD)"r>k
D^{:UbN
(org.flyware.util.page.Page) Z^l!y5s/H
*/ *J=ol
publicList getUserByPage(Page page)throws 1`t?5|s>
NZuFxJ-`
HibernateException { THp `!l
String querySentence = "FROM user in class v\eBL&WK
EHHxCq?
com.adt.po.User"; H^g<`XEgw
Query query = getSession().createQuery C] w< &o
6~S0t1/t?
(querySentence); U!5*V9T~J
query.setFirstResult(page.getBeginIndex()) (n/1:'
.setMaxResults(page.getEveryPage()); )8SP$
return query.list(); {+:XVT_+
} &>{>k<z
m { fQL
} ar|[D7Xrq\
\gkajY-?
yh:,[<q
cZ >W8{G
L'Zud,JKg
至此,一个完整的分页程序完成。前台的只需要调用 3c3Z"JV
3Y-v1.^j
userManager.listUser(page)即可得到一个Page对象和结果集对象 H~i],WD
81cmG`G7
的综合体,而传入的参数page对象则可以由前台传入,如果用 q1Sm#_7
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webwork,甚至可以直接在配置文件中指定。 zf~zYZSr
7
L\?
下面给出一个webwork调用示例: to 6Q90(
java代码: y7OG[L/
BT3O_X`u
@E2nF|N
/*Created on 2005-6-17*/ ntV>m*^
package com.adt.action.user; NO^t/(Z
]LTc)[5Zj
import java.util.List; <h=M
Rw,l
?<'W~Rm6n
import org.apache.commons.logging.Log; %
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>
import org.apache.commons.logging.LogFactory; J36@Pf]h
import org.flyware.util.page.Page; S(i(1Hs.
b<AE}UK
import com.adt.bo.Result; Ba0D"2CgY
import com.adt.service.UserService; yXx62J
import com.opensymphony.xwork.Action; PEEY;x
bOMP8{H,
/** ZPao*2xz
* @author Joa MPn>&28"|K
*/ )`mF.87b&h
publicclass ListUser implementsAction{ >;v0zE
5R `6zhf
privatestaticfinal Log logger = LogFactory.getLog \STvBI?
B5HdC%8/}
(ListUser.class); vXyo
f+Me dc~
private UserService userService; W;dzLgc
]a#]3(o]}
private Page page; FM"BTA:C
~#_$?_/(
privateList users; lMez!qx,=
5,BkwAr+6[
/* y=xe<#L
* (non-Javadoc) g/Jj]X#r
* jA4v?(AO}#
* @see com.opensymphony.xwork.Action#execute() $L8s/1up
*/ K)UOx#xe1
publicString execute()throwsException{ "!6~*!]c
Result result = userService.listUser(page); 8M+F!1-#
page = result.getPage(); xKST-:c +
users = result.getContent(); P=[x!}.I
return SUCCESS; h)
PB
} up3<=u{>
ysJhP .
/** OCO,-(
* @return Returns the page. ' 5 qL
*/ ({kGK0
public Page getPage(){ S aet";pf`
return page; >ha Ixs`9
} zMzf=~
^%$W S,
/** LY!3u0PnlT
* @return Returns the users. ;
9&.QR(
*/ ,
gr&s+
publicList getUsers(){ GVc[p\h(
return users; /\uH[[s
} .Xz"NyW
#u5;utY:F
/** S%s|P=u
* @param page "jJdUFN
* The page to set. >wk=`&+V@
*/ b;`#Sea
publicvoid setPage(Page page){ 1\J1yOL
this.page = page; DD6`k*RIk.
} us,,W(q
VueQP|
/** '`~(Fkj
* @param users `{Di*
* The users to set. p9}c6{Wp
*/ |XA aKZA
publicvoid setUsers(List users){ t2%@py*bU
this.users = users; >`?+FDOJ,
} VmH_0IM^6
V<NsmC=g
/** b:5%}
* @param userService [xs)u3b
* The userService to set. m>-^K
*/ u3i|}`
publicvoid setUserService(UserService userService){ "ko?att~
this.userService = userService; M3;v3
}z<-
} C`~4q<W'
} F;&fx(
9k+&fyy
(T#(A4:6S
vl{_M*w
;
m57tOX
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, S}p&\w H
yZ~eLWz
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 %)hIpxOrX
Or#+E2%1E
么只需要: #
/,2MQ
java代码: {{[jC"4AY
ic{.#R.BY
&0
)xvZ
<?xml version="1.0"?> ZJI1NCBZ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Up/u|A$0V
JXRf4QmG
1.0//EN" "http://www.opensymphony.com/xwork/xwork- (zw=qbS&
"G-0i KW;
1.0.dtd"> 60~>f)vu
b^l
-*4
<xwork> ;$tv8%_L[
3{I=#>;
<package name="user" extends="webwork- seqF84Xd<
7k#${,k
interceptors"> Dss/>!
mN
zEPx
<!-- The default interceptor stack name z1SMQLk
oB{}-[G
--> "J[i=~(
<default-interceptor-ref 400Tw`AiJ
G0;EbJ/&
name="myDefaultWebStack"/> WP@JrnxO\`
<;,S"e
<action name="listUser" Th;gps%b
J.e8UQ@=5
class="com.adt.action.user.ListUser"> D@rn@N
<param ! N"L`RWD
g"dZB2`C
name="page.everyPage">10</param> \l=KWa 3Q
<result Q1ABnacR
qJFgbq4-
name="success">/user/user_list.jsp</result> K@j^gF/0B
</action> c]aK
N
;/)Mcx] n
</package> :U-US|)(2
^;CR0.4
</xwork> RqN_vk\
u5{5ts+:
DtJTnvG~B
++Ys9Y)*,
4<3?al&
v1"g!%U6
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 ej"o?1l@
8F`BJ6='
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。 \{MrQ2jd
w[,?-Xm
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 gSv[4,hXd
L%o6 5
8W1K3[Jj<
.y;\puNq
9OQ0Yc!3
我写的一个用于分页的类,用了泛型了,hoho kP}hUrDX5
Fyh?4!/.
java代码: 2*-ENW2
yjOu]K:X
1W}nYU
package com.intokr.util; kh>SrW]B%
'!yS72{$2
import java.util.List; g@k#J"Q'[
,2
g M-
/** ]4 K1%ZV
* 用于分页的类<br> .n)!ZN
* 可以用于传递查询的结果也可以用于传送查询的参数<br> M]4 =(Vv+5
* h[-d1bKwS
* @version 0.01 =mi:<q
* @author cheng aX[1H6&=7
*/ x'=3&vc4
public class Paginator<E> { P+;CE|J`X
privateint count = 0; // 总记录数 #A|D\IhF
privateint p = 1; // 页编号 L)R[)$2(g
privateint num = 20; // 每页的记录数 ^ =/?<C4
privateList<E> results = null; // 结果 6<qwP?WN
sx[&4 k[
/** %eutfM-?6
* 结果总数 ;Oi[:Ck
*/ \&\_>X.,
publicint getCount(){ 20.-;jK
return count; i!1ho T$
} _\4`
56bud3CVs
publicvoid setCount(int count){ ]e@0T{!
this.count = count; !e:iB7<
} {;Y 89&*R
k"q!|+&Fs
/** E,<\T6/%q
* 本结果所在的页码,从1开始 .0Iun+nUD
* QX/X {h6
* @return Returns the pageNo. *%OYAsc
*/ Hyq@O8
publicint getP(){ 't0+:o">:
return p; v.l7Q
} Xx3g3P
w'oo-.k
/** z_:eM7]jv
* if(p<=0) p=1 J0ZxhxX35
* XSm"I[.g
* @param p wQD0vsD
*/ 4GU/V\e|
publicvoid setP(int p){ eq@am(#&kY
if(p <= 0) <THZ2`tTK3
p = 1; Ci7P%]9
this.p = p; (B_7\}v|_
} jb|mip@`
<
%1-K);SJ
/** e-CNQnO~
* 每页记录数量 X$7Oo^1;
*/ h&=O-5
publicint getNum(){ |
((1V^
return num; T~i%j@Q.6
} w24{_ N
JmU<y
/** GI2eJK
* if(num<1) num=1 "3{#d9Gs
*/ >63)z I
publicvoid setNum(int num){ }}^,7npU
if(num < 1) +Dx1/I
num = 1; j[J5y#
this.num = num; YG0Px Zmi
} C5O5S:|'
B :.@Qi^
/** GXDC@+$14
* 获得总页数 &8[ZN$Xe"
*/ YCa@R!M*O
publicint getPageNum(){ KQG-2oW
return(count - 1) / num + 1; 7d&DrI@~
} %
v;e
d]tv'|E13
/** [[:UhrH-
* 获得本页的开始编号,为 (p-1)*num+1 tigT@!`$Y
*/ J>rka]*
publicint getStart(){ 9R9__w;
return(p - 1) * num + 1; Y3#Nux%
} 6g5PM4\
QWrIa1.JC
/** y[:
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* @return Returns the results. /@ y;iJk;
*/ si_W:mLF{a
publicList<E> getResults(){ c |>=S)|
return results; 21r==
H$
} '3A+"k-}mh
2O
eshkE
public void setResults(List<E> results){ K(<$.
this.results = results; 8zhBA9Y#~
} y }\r#"Z`
x^A7'ad0
public String toString(){ ""co6qo#>
StringBuilder buff = new StringBuilder 1HMUHZT
T4mv%zzS
(); q@(1Yivk
buff.append("{"); zVSx$6eiU
buff.append("count:").append(count); f}^I=pS&
buff.append(",p:").append(p); \+-zRR0
buff.append(",nump:").append(num); +' %@!
buff.append(",results:").append 5L8&/EN9-
^:`oP"%-T
(results); ~12_D'8D[
buff.append("}"); "`pNH'
return buff.toString(); S]}}A
} n.*3,4.]
\tY"BC4.
} {P-xCmZ~Wt
GL1'Zo
JPEIT