Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 j
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ;r.EC}>m
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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 -jB3L:
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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 ziiwxx_
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。 \9`#]#1bx5
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分页支持类: `<U5z$^QTw
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java代码: H]&gW/=
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package com.javaeye.common.util; 22&;jpL'?
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import java.util.List; py
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publicclass PaginationSupport { <F(><Xw,-4
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publicfinalstaticint PAGESIZE = 30; wksl0:BL
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privateint pageSize = PAGESIZE; 19W:-Om
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privateList items; H; Ku
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privateint totalCount; X:|8vS+0gU
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privateint[] indexes = newint[0]; O6X"RsI}
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privateint startIndex = 0; 6~xBi(m`
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public PaginationSupport(List items, int qtMD CXZ^n
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totalCount){ .UQE{.?
setPageSize(PAGESIZE); i{Ds&{
setTotalCount(totalCount); <CZgQ\Mt
setItems(items); , jU5|2
setStartIndex(0); $!B}$I;cd
} ;j9\b9m
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public PaginationSupport(List items, int x#*QfE/E(@
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totalCount, int startIndex){ 9t$]X>}
setPageSize(PAGESIZE); %%JMb=!%2
setTotalCount(totalCount); AXPMnbUS
setItems(items); ~Lz%.a;o
setStartIndex(startIndex); tU:EN;H
} q%i-`S]}qL
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public PaginationSupport(List items, int Lja 7
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totalCount, int pageSize, int startIndex){ {<=#*qx[Y!
setPageSize(pageSize); yK%ebq]
setTotalCount(totalCount); @7<uMasfp
setItems(items); (Un_!)
setStartIndex(startIndex); k|xtr&1N.!
} F(,UA+$A
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publicList getItems(){ Fmr}o(q1
return items; t:)ERT")
} e<cM[6H'D
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publicvoid setItems(List items){ +>\id~c(
this.items = items; MTOy8 Im
} eE@&ze>X
}4//@J?:
publicint getPageSize(){ g(|{')8?d
return pageSize; AUe# RP
} ~1L:_Sg*
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publicvoid setPageSize(int pageSize){ 7.g[SBUOG
this.pageSize = pageSize; t2BL(yB
} ,|kDsR!
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publicint getTotalCount(){ om h{0jA0
return totalCount; 7U|mu~$.!
} 0#cy=*E
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publicvoid setTotalCount(int totalCount){ _zWfI.o
if(totalCount > 0){ De&6 9
this.totalCount = totalCount; ACq7dLys,B
int count = totalCount / p< "3&HA
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pageSize; cLVe T
if(totalCount % pageSize > 0) tptN6Isuh
count++; OTDg5:>
indexes = newint[count]; H1n1-!%d
for(int i = 0; i < count; i++){ NMOut@
indexes = pageSize * QPtGdd
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i; c%m3}mrb
} U.!lTLjfLz
}else{ !> }.~[M
this.totalCount = 0; ~{,X3-S_H
} 6/V3.UP-
} y:m_tv0~0
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publicint[] getIndexes(){ a^d8I
return indexes; :j }fC8'
} zOgTQs"ZH
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publicvoid setIndexes(int[] indexes){ uvP2Wgt
this.indexes = indexes; YjOs}TD lx
} ' Z0r>.
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publicint getStartIndex(){ 5NoI~X=
return startIndex; /zDi9W*~1
} I`KQ|h0%
w }^ I
publicvoid setStartIndex(int startIndex){ ?`zXLY9q7
if(totalCount <= 0) r$Co0!.
this.startIndex = 0; n_ lo`
elseif(startIndex >= totalCount) &e-U5'(6v_
this.startIndex = indexes r%:+$aIt
1$qh`<\
[indexes.length - 1]; M" ^PW,k
elseif(startIndex < 0) < -W*$?^
this.startIndex = 0; MUfG?r\t
else{ Q'_z<V
this.startIndex = indexes tyaA\F57
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[startIndex / pageSize]; H"ZZ.^"5FV
} E|'h]NY
} M@0;B30L
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publicint getNextIndex(){ 2{|h8oz
int nextIndex = getStartIndex() + L_=3<nE
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pageSize; jReXyRmo({
if(nextIndex >= totalCount) Xp0F
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return getStartIndex(); u#}[ZoI
else x#Sqn#
return nextIndex; F 8B#}%JE
} g1t0l%_7^
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publicint getPreviousIndex(){ AL>$HB$
int previousIndex = getStartIndex() - Jgnhn>dHe
o sKKt?^?
pageSize; 23~Sjr
if(previousIndex < 0) Xy5e5K
return0; 8Q_SRwN
else 8\:NMP8W\
return previousIndex; p<M\U"5Ye
} Y>'|oygHA
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} 5mb]Q)f9-
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抽象业务类 xyI}y(CN1
java代码: 7jdb)l\p=
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/** 9K1oZ?)_z
* Created on 2005-7-12 %2v4<icvq
*/ ,\NFt`]j
package com.javaeye.common.business; lok=
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import java.io.Serializable; )ZN|t?|
import java.util.List; u*hSj)vr1
Z?\>JM >;
import org.hibernate.Criteria; !"Oh36
import org.hibernate.HibernateException; :0h_K
import org.hibernate.Session; G37U6PuZi
import org.hibernate.criterion.DetachedCriteria; h<$MyN4]g
import org.hibernate.criterion.Projections; i[ mEi|
import }sxYxn~
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A
org.springframework.orm.hibernate3.HibernateCallback; Dc,I7F|%
import 'q`^3&E
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org.springframework.orm.hibernate3.support.HibernateDaoS E~6c -Lw
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r{5
upport; w!D|]LoE
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import com.javaeye.common.util.PaginationSupport; 9Q"'"b*?z
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public abstract class AbstractManager extends ;3@cy|\:
(SvWvm
HibernateDaoSupport { |j7,Mu+
/FRm2m83
privateboolean cacheQueries = false; OLE[UXD-E
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privateString queryCacheRegion; jbAx;Xt'=M
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publicvoid setCacheQueries(boolean 'ET~
: 2EDjW
cacheQueries){ 2 O%`G+\)
this.cacheQueries = cacheQueries; *6>.!&
} >G%o,9i
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publicvoid setQueryCacheRegion(String }9FSO9*&}
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queryCacheRegion){ BBev<
this.queryCacheRegion = T
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queryCacheRegion; \pVXimam
} r4SXE\
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publicvoid save(finalObject entity){ \RG8{G,
getHibernateTemplate().save(entity); bJX)$G
} N(Tz%o4
@"^0%/2-
publicvoid persist(finalObject entity){ oaIi2=Tf
getHibernateTemplate().save(entity); C)`Fv=]R
} 85LAYaw
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publicvoid update(finalObject entity){ j3{D^|0bP
getHibernateTemplate().update(entity); yjF1}SQ
} 7Mg=b%IYs
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publicvoid delete(finalObject entity){ 0|{u{w@!`
getHibernateTemplate().delete(entity);
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} ~
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publicObject load(finalClass entity, =ACVE;L?
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finalSerializable id){ &tg&5_
return getHibernateTemplate().load FG.em
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(entity, id); {?:X8&Sf
} Hl{S]]z
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publicObject get(finalClass entity, sT}.v*
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finalSerializable id){ }&wUr>=
return getHibernateTemplate().get ^c9t'V`IWQ
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(entity, id); +JjW_Rl?=V
} n[lJLm^(_C
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publicList findAll(finalClass entity){ {y=j?lD
return getHibernateTemplate().find("from iO|se:LY<
iOW#>66d
" + entity.getName()); Ab{ K<:l
} W04@!_) <
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publicList findByNamedQuery(finalString H|3:6x
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namedQuery){ 2N: ,Q8~
return getHibernateTemplate [YlKR'_
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().findByNamedQuery(namedQuery); ;DFSzbF`
} snobT Q
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publicList findByNamedQuery(finalString query, n*[XR`r}
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finalObject parameter){
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return getHibernateTemplate >\KNM@'KI
u{['<r;I
().findByNamedQuery(query, parameter); RI(DXWM|h
} Ya3C#=
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publicList findByNamedQuery(finalString query, 0i!uUF
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finalObject[] parameters){ |}BLF
return getHibernateTemplate F \KjEl0
bDL,S?@
().findByNamedQuery(query, parameters); |H;F7Y_
} ,JAx
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publicList find(finalString query){ pwL;A3$|
return getHibernateTemplate().find =;Rtdy/Yn%
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(query); -GhP9; d
} [q?<Qe
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publicList find(finalString query, finalObject ;z}i-cNae
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parameter){ o<BOYrS
return getHibernateTemplate().find ?!A7rb/tj
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(query, parameter); 8']M^|1
} e7Xeo +/
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public PaginationSupport findPageByCriteria ,(d)Qg
oHd FMD@
(final DetachedCriteria detachedCriteria){ 7}f}$1
return findPageByCriteria 2Rw&C6("w
TC!Yb_H}gN
(detachedCriteria, PaginationSupport.PAGESIZE, 0); U>=Z-
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} _aGOb;h
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public PaginationSupport findPageByCriteria ?Y-%'J(
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(final DetachedCriteria detachedCriteria, finalint ^1iSn)&
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startIndex){ l=S 35og
return findPageByCriteria q rJ`1
n.'8A(,r3
(detachedCriteria, PaginationSupport.PAGESIZE, x+Ttl4
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startIndex); >`Y.+4mE
} #hfXZVD
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public PaginationSupport findPageByCriteria Uzz'.K(Mv|
rI= v
(final DetachedCriteria detachedCriteria, finalint gw#5jW\
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pageSize, g7}Gip}.>
finalint startIndex){ 1C}NQ!.
return(PaginationSupport) .k,1f*%
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getHibernateTemplate().execute(new HibernateCallback(){ ciBP7>'::
publicObject doInHibernate h`KFL/fT
hn5h\M?
(Session session)throws HibernateException { G`SUxhC k
Criteria criteria = K0-ypU*P
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detachedCriteria.getExecutableCriteria(session); 5]KW^sL
int totalCount = |^: cG4e
B~ ]k#Ot)
((Integer) criteria.setProjection(Projections.rowCount FQu8vwV6>
)Xk0VDNp$/
()).uniqueResult()).intValue(); t2/#&J]
criteria.setProjection 6IBgt!=,
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(null); R)_%i<nq\
List items = fol,xMc&
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criteria.setFirstResult(startIndex).setMaxResults KK&rb~
<;vbsksZeH
(pageSize).list(); f,h J~
PaginationSupport ps = h].<t&
"$#xK |t
new PaginationSupport(items, totalCount, pageSize, @Z*W
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startIndex); >.Chl$)<
return ps; YLqGRE`W
} $bW3_rl%X
}, true); L^E[J`
} _,p/l&<
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public List findAllByCriteria(final ?oVx2LdD|
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DetachedCriteria detachedCriteria){ OVm\
return(List) getHibernateTemplate X &uTSgN
/xsF90c\h
().execute(new HibernateCallback(){ }+)fMZz
publicObject doInHibernate l==``
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(Session session)throws HibernateException { +AR5W(&
Criteria criteria = ^N7e76VwR
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detachedCriteria.getExecutableCriteria(session); x.7]/)
return criteria.list(); #*QO3y~ZM
} M9!HQ
}, true); sx7eC
} 6N!Q:x^4(T
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public int getCountByCriteria(final )Q1"\\2j0
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DetachedCriteria detachedCriteria){ kh
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Integer count = (Integer) 4]yOF_8h
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getHibernateTemplate().execute(new HibernateCallback(){ -&NN51-d\j
publicObject doInHibernate 6VS4y-N
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(Session session)throws HibernateException { QN
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Criteria criteria = "Ue.@>
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detachedCriteria.getExecutableCriteria(session); '10oK {m$
return j}%ja_9S
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criteria.setProjection(Projections.rowCount d6'{rje(
c9HrMgW
()).uniqueResult(); *AG#316
} <oR a3Gi(%
}, true); k[bD\'
return count.intValue(); &,}j#3<
} JW{rA6?
} q)Lu_6 mg
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用户在web层构造查询条件detachedCriteria,和可选的 C9~52+S
",^Mxm{
startIndex,调用业务bean的相应findByCriteria方法,返回一个 kqM045W7
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PaginationSupport的实例ps。 !F1M(zFD
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ps.getItems()得到已分页好的结果集 9{(.Il J>
ps.getIndexes()得到分页索引的数组 /q<__N
ps.getTotalCount()得到总结果数 &:/hrighH
ps.getStartIndex()当前分页索引 x.f]1S7h[
ps.getNextIndex()下一页索引 fI{E SXU
ps.getPreviousIndex()上一页索引 tasIDoo+!J
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 qCljo5Tq'
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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 G`n_YH084
<L"GqNuRQ
一下代码重构了。 v{(^1cX
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我把原本我的做法也提供出来供大家讨论吧: R$q;
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首先,为了实现分页查询,我封装了一个Page类: U>cV|
java代码: \!k1a^ZP
d/ARm-D
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/*Created on 2005-4-14*/ &X|#R1\
package org.flyware.util.page; e7m*rh%5>
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/** P*
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* @author Joa eCqHvMp
* XiL~TCkx4
*/ |2RC# ]/-Y
publicclass Page { jBgP$g
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/** imply if the page has previous page */ !9[>L@#G
privateboolean hasPrePage; )+[ gd/<C.
{4G%:09~J
/** imply if the page has next page */ d{SG
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privateboolean hasNextPage; Jth[DUH8H
[U5\bX@$
/** the number of every page */ {U1?Et#
privateint everyPage; Oy%''+g
M-1ngI0H;
/** the total page number */ fz\9 S
privateint totalPage; t"=
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/** the number of current page */ mVVD!
privateint currentPage; +3BBQ+x!
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/** the begin index of the records by the current ZZHDp&lh}
)/pU.Z/
query */ DVSL [p?_
privateint beginIndex; np8gKVD
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/** The default constructor */ .!f$
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public Page(){ (-ufBYO6
MUTj-1 H6)
} iPd[l{85Z
*h'=3w:G
/** construct the page by everyPage 0w)^)
* @param everyPage l:j4Ft 8
* */ |N%fMPKa
public Page(int everyPage){ In18_bc
this.everyPage = everyPage; U.DDaT1
} Hea;?4Vg
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/** The whole constructor */ 8,C*4y~
public Page(boolean hasPrePage, boolean hasNextPage, y~q8pH1
T)H{
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int everyPage, int totalPage, q35f&O;
int currentPage, int beginIndex){ 7]blrN]
this.hasPrePage = hasPrePage; 4)A#2
this.hasNextPage = hasNextPage; ,Wk?I%>
this.everyPage = everyPage; H."EUcE{
this.totalPage = totalPage; d-k%{eBV
this.currentPage = currentPage; {]:7bV#JP
this.beginIndex = beginIndex; U)E(`{p]
} >8k_n
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/** /atW8 `&
* @return R)QC)U
* Returns the beginIndex. /ro=?QYb
*/ f33 l$pOp
publicint getBeginIndex(){ - `p4-J!Fy
return beginIndex; L&u$t}~)
} @cFJeOC|
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/** xlA$:M&
* @param beginIndex vUohtS*
* The beginIndex to set. 3NqN\5B:
*/ _*1`@
publicvoid setBeginIndex(int beginIndex){ L)@?e?9
this.beginIndex = beginIndex; M<kj_.
} BT}!W`
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/** 1Cv-
* @return ?u "
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* Returns the currentPage. mF,Y?ax
*/ zi]\<?\X
publicint getCurrentPage(){ &Low/Y'.jJ
return currentPage; s'%R
}
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/** 59"UL\3
* @param currentPage 3|'>`!hb
* The currentPage to set. #~C]ZrK
*/ xI($Uu}S
publicvoid setCurrentPage(int currentPage){ M$/|)U'W
this.currentPage = currentPage; ^j31S*f&:
} +^=8ge}
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/** UA48Ug
* @return *>n;SuT_
* Returns the everyPage. {>DEsO
*/ qz0;p=$8Z
publicint getEveryPage(){ Y]/%t{Y
return everyPage; $}>+kHoT{
} +@p%
p
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/** y5*Z3"<
* @param everyPage =a@j=
* The everyPage to set. x{n`^;Y1
*/ l5Gq|!2yxD
publicvoid setEveryPage(int everyPage){ P<X\%_Iat
this.everyPage = everyPage; n1ly
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} H!5\v"]WB
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/** ]:Nsf|C0
* @return Yu)NO\3&
* Returns the hasNextPage. f!I[>&n
*/ GO`Ru 8
publicboolean getHasNextPage(){ $\]&rZVi
return hasNextPage; El.hu%#n*G
} C8Qa$._
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/** VF?<{F
* @param hasNextPage [RLN;(0n
* The hasNextPage to set. =5/9%P8j9
*/ ?[g=F <r
publicvoid setHasNextPage(boolean hasNextPage){ "Zl5<
this.hasNextPage = hasNextPage; fI{&#~f4C
} T
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/** r:f[mk"-"A
* @return S-
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* Returns the hasPrePage. K/i*w<aPb7
*/ `6lr4Kk @R
publicboolean getHasPrePage(){ V^3L3|k
return hasPrePage; ]xRM&=)<
} >7I15U
1*'HL#
/** *>|gxM8
* @param hasPrePage +
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* The hasPrePage to set. gQ'zW
*/ oU056
publicvoid setHasPrePage(boolean hasPrePage){ g!lWu[d
this.hasPrePage = hasPrePage; $Tu61zq
} iV'k}rXC
o4m\~as)Y
/** k5:G-BQ:
* @return Returns the totalPage. 9
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* Nl^;A><u
*/ $ M`hh{ -
publicint getTotalPage(){ M?Dfu
.t
return totalPage; DI:]GED"=
} NdMb)l)m
nuk*.Su
/** =Xi07_8Ic<
* @param totalPage GFeQ%l`7F
* The totalPage to set. Qw-~>d
*/ QEz?w}b*
publicvoid setTotalPage(int totalPage){ dIN$)?aB0
this.totalPage = totalPage; L^}_~PO N5
} AK'[c+2[
&;^YBW :I
} }=<
YC++&Nk
Z/k:~%|E
kW;+|qs^
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 llcb~
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个PageUtil,负责对Page对象进行构造: |TS>hwkI
java代码: '[AlhBX
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jf4
/*Created on 2005-4-14*/ `uOT+B%R
package org.flyware.util.page; \MyLc/Gh5
11o.c;
import org.apache.commons.logging.Log; t;W0"ci9
import org.apache.commons.logging.LogFactory; \.MR""@y`{
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/** L
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* @author Joa >V-A;S:
* [@VP?74
*/ */sS`/Lx
publicclass PageUtil { ojcA<60
'
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privatestaticfinal Log logger = LogFactory.getLog [tlI!~Z
'(U-(wTC'/
(PageUtil.class); |iak z|])
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/** 7j@Hs[
*
* Use the origin page to create a new page t|g4m[kr
* @param page C 3^JAP
* @param totalRecords -`'I{g&A
* @return R%{<mno/_
*/ SIBtmm1W
publicstatic Page createPage(Page page, int 7''??X
A,JmX
totalRecords){ ns9U/:L
return createPage(page.getEveryPage(), /rK}?U
(?n=33}Ci
page.getCurrentPage(), totalRecords); 8EW_V$>R
} f.D?sH An
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/** TrlZ9?3#D
* the basic page utils not including exception mWoAO@}Y
o}
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handler s^Y"' ` +
* @param everyPage $Q &lSVQ
* @param currentPage |cK*~
* @param totalRecords vx>b^tJKC
* @return page `7c~mypx
*/ %Qmn-uZ
publicstatic Page createPage(int everyPage, int ;D3C>7y
e|)hG8FlF
currentPage, int totalRecords){ CyJEY-
everyPage = getEveryPage(everyPage); Bo)3!wO8
currentPage = getCurrentPage(currentPage); Rw"sJ) /
int beginIndex = getBeginIndex(everyPage, CS2Bo
( /=f6^}
currentPage); MLXN Zd
int totalPage = getTotalPage(everyPage, GZEc l'h*
?4+9fE<Q
totalRecords); } df
W%{
boolean hasNextPage = hasNextPage(currentPage, 5 h-@|t
s3z$e+A8
totalPage); IdzxS
boolean hasPrePage = hasPrePage(currentPage); v:IpMU-+\
WffQ :L?
returnnew Page(hasPrePage, hasNextPage, &-;4.op
everyPage, totalPage, zNs55e.rx
currentPage, xcd#&
S=MEG+Ad
beginIndex); ?:vv50
} RiDJ> 6S
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privatestaticint getEveryPage(int everyPage){ ~5NXd)2+Ks
return everyPage == 0 ? 10 : everyPage; \d6C%S!
} = I:.X ;
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privatestaticint getCurrentPage(int currentPage){ 51#_Vg
return currentPage == 0 ? 1 : currentPage; vx1c,8
} '.on)Zd.
dzARI`
privatestaticint getBeginIndex(int everyPage, int =b%MXT
1a?!@g)
currentPage){ O9G[j=U
return(currentPage - 1) * everyPage; }u\])I3
} $:8x(&+/@
V\>K]mwD
privatestaticint getTotalPage(int everyPage, int (SWYOMo"
!>@V#I
totalRecords){ Qn3+bF4
int totalPage = 0; ;,})VoC\!
6:z&ukqE
if(totalRecords % everyPage == 0) 3L]^x9Cu)
totalPage = totalRecords / everyPage; )Qj9kJq
else Q0; gF?
totalPage = totalRecords / everyPage + 1 ; 4$2T zJE
}Z?[Ut
return totalPage; (l_de)N7
} [}>6n72gNh
VdOd:w
privatestaticboolean hasPrePage(int currentPage){ }R5&[hxh4t
return currentPage == 1 ? false : true; * !Y3N<>!
} JI,hy
<3l0
.*f4e3
privatestaticboolean hasNextPage(int currentPage, *g41"Cl
5XUI7Q%
int totalPage){ BXv)zE=j
return currentPage == totalPage || totalPage == d1La7|43u
$K5s)!
0 ? false : true; i@^`~vj
} <0
idG
oNsx Fi:
PW<wjf,rQ
} cRr `r[t
MNmQ%R4jRN
9k^=m)yS'
iC+H;s5<
o5x^ "#
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 /0B?3&H
{lUl+_58
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ;1k0o.3
}t-|^mY>
做法如下: 3}1+"? s
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >qvD39w
jeFl+K'1
的信息,和一个结果集List: ]b| @<E7Y
java代码: <d`UifqD
6i9I 4*'
2^M+s\p
/*Created on 2005-6-13*/ ^ED>{UiNI
package com.adt.bo; Df3v"iCq}
h1o+7
import java.util.List; h#ot)m|I
E+Mdl*
import org.flyware.util.page.Page; b}*bgx@<
&Q+V I/p
/** ',j-n$Z^=
* @author Joa BD#;3?|
*/ ]~Qk g+>'&
publicclass Result { /iuNdh
GZX!iT
private Page page; ~(]DNXB8I`
,ToEKId
private List content; 8HA=O?Cg
j5^b~F%
/** M':.b+xN
* The default constructor ZSt
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*/ B8Zd#.6]
public Result(){ *bSG48W("
super(); ~At.V+
} 'oL[rO~j
Li^!OHro.
/** c6)zx
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* The constructor using fields kxwm08/|f
* O^%ace1
* @param page !|c5@0Wr
* @param content Y,\mrW}K
*/ (Fd4Gw<sq
public Result(Page page, List content){ io3'h:+9s
this.page = page; K(<P" g(
this.content = content; #7ZBbq3=
} /n:fxdhe
rNC3h"i\
/** R\amcQ
9
* @return Returns the content. kl"Cm`b)
*/ )d`$2D&iY
publicList getContent(){ !P3|T\|]+
return content; M0
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} oU? X"B9
RR=l&uT
/** %BLKB%5
* @return Returns the page. !{lb#
*/ d6&tz!f
public Page getPage(){ 9Wrclai
return page; 9<mj@bI$
} GqxK|G1
b;l%1x9r
/** 1*jm9])#
* @param content iL1so+di
* The content to set. cEu98nP
*/ cfS]C_6d
public void setContent(List content){ nHjwT5Q+Q
this.content = content; gMn)<u >
} jQ}|]pj+
sTyGi1
/** /^G+vhlf\
* @param page $7YLU{0
* The page to set. _Y {g5t
*/ b] V=wZ
o
publicvoid setPage(Page page){ _*I6O$/>
this.page = page; ek!N eu>
} IPR396J+-
} 32D/%dHC
S:QEHd_C
?K 0V#aq
Y,~]ecI
<~w#sIh
2. 编写业务逻辑接口,并实现它(UserManager, Xii#Qtd.
IA`
UserManagerImpl) b@hoH)<9E
java代码: |D:0BATRP
(p!AX<=z
-<=<T@,
/*Created on 2005-7-15*/ Lp=B? H
package com.adt.service; Q pq0j^\
{*9i}w|2
import net.sf.hibernate.HibernateException; ?]N&H90^5
Q-5wI$=
import org.flyware.util.page.Page; bmpB$@
e:
tp7w 4
import com.adt.bo.Result; Q2JjBV<
a mgex$
/** hd-ds~ve
* @author Joa "(qO}&b>
*/ my6T@0R
publicinterface UserManager { (eP)>G]
t:7jlD!d
public Result listUser(Page page)throws k$!&3Rh
Rw`s O:eZ
HibernateException; CuNHDYQ&3
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} ppjrm
nv]64mL3
[bXZPIz;j
>2/zL.O
mgWtjV 8
java代码: j Xf-+;ZQ
W+X
zU"l
f?6=H^_>
/*Created on 2005-7-15*/ bX1ip2X
lk
package com.adt.service.impl; FC#Qtu~J
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o
import java.util.List; /([aD~.
x;Q2/YZ#
import net.sf.hibernate.HibernateException; uItKs u
w5Xdq_e3
import org.flyware.util.page.Page; <T]kpP<lC
import org.flyware.util.page.PageUtil; )FLpWE"e-
VK#zmEiB
import com.adt.bo.Result; qxx.f58H
import com.adt.dao.UserDAO; }f}&|Vap
import com.adt.exception.ObjectNotFoundException; l-rnDl
import com.adt.service.UserManager; -j,o:ng0
=[&Jxy>Y
/** </QSMs
* @author Joa .9ne'Ta
*/ *#_jTwQe
publicclass UserManagerImpl implements UserManager { S0 `*
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private UserDAO userDAO; ",m5}mk:4
xT/&'$@{)
/** b+>godTi_
* @param userDAO The userDAO to set. a=R-F!P)
*/ ;D:v@I$I
publicvoid setUserDAO(UserDAO userDAO){ nj[6c
this.userDAO = userDAO; 4]GyuY
} K VCS(oN
"x11 YM{F
/* (non-Javadoc) 5cU8GgN`
* @see com.adt.service.UserManager#listUser g2I @j3
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(org.flyware.util.page.Page) ilP&ctn6+c
*/ ,J~dER\%
public Result listUser(Page page)throws .\ZxwD|
:lAR;[WFS
HibernateException, ObjectNotFoundException { 4/4IZfznX
int totalRecords = userDAO.getUserCount(); I}X8-WFB
if(totalRecords == 0) u(R`}C?P'
throw new ObjectNotFoundException *))|ZE6jI
M<nn+vy`
("userNotExist"); ~xCy(dL^}
page = PageUtil.createPage(page, totalRecords); fu/c)D6u*m
List users = userDAO.getUserByPage(page); sAb|]Q((
returnnew Result(page, users); H;6V
} o>YRKb
2-4%h!
} oaHBz_pg
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*K;~V
2+.m44>Ti
z!%}0
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 e#wn;wo?
$f+9svq
询,接下来编写UserDAO的代码: bpzA '
g>
3. UserDAO 和 UserDAOImpl: <bH>\@p7}
java代码: Z&%61jGK
wa C%o%fD
VYBl0!t
/*Created on 2005-7-15*/ cmTZ))m
package com.adt.dao; epnDvz\
O
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import java.util.List; ]q j%6tz
7j
Q`i;L}Y
import org.flyware.util.page.Page; e|I5Nx2)
,RZktWW_
import net.sf.hibernate.HibernateException; R?W8l5CIk
j{vzCRa>8
/** MI/1uw
* @author Joa xASjw?
*/ xiI!_0'
publicinterface UserDAO extends BaseDAO { (.c?)_G,
yVL~SH|
publicList getUserByName(String name)throws [;(|^0
`{ /tx!
HibernateException; y&
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publicint getUserCount()throws HibernateException; u1uY*p
K"pfp !Y
publicList getUserByPage(Page page)throws 1#'wR3[+
NS1[-ng
HibernateException; ,MLPVDN*D
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} loZfzN&6A
Na=q(OKN
ukw'$Yt2
dL"v*3Fy
()7=(<x{
java代码: NM4 n
lBCM;#P
&(K*TB|Om
/*Created on 2005-7-15*/ f /jN $p
package com.adt.dao.impl; Gqs8$[o
SbB5J> >7J
import java.util.List; Z'EZ PuZ!'
rg`"m
import org.flyware.util.page.Page; /ZczfM\
*"#>Ov>
import net.sf.hibernate.HibernateException; GB-=DC6
import net.sf.hibernate.Query; lY~xoHT;[
,Zdc
import com.adt.dao.UserDAO; t~Uqsa>n@'
+h
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/** 'K0Y@y
* @author Joa os>|LPv4
*/ 9TF[uC)-2
public class UserDAOImpl extends BaseDAOHibernateImpl DI*xf
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implements UserDAO { rO-Tr
}p#S;JZRu+
/* (non-Javadoc) (\Dd9a8V-
* @see com.adt.dao.UserDAO#getUserByName .G^.kg ,
Cc=`:ED+
(java.lang.String) 9 Hm!B )Y
*/ bC&_OU:
publicList getUserByName(String name)throws U $+rlw}
l_8t[
HibernateException { s?=J#WV1y
String querySentence = "FROM user in class ,3^N_>d$W
Tj>~#~
com.adt.po.User WHERE user.name=:name"; i$ Zhk1
Query query = getSession().createQuery Xdjxt?*
*bZV4}
(querySentence); !D1F4v[c=
query.setParameter("name", name); ?^yZVmAo]
return query.list(); I3SLR
} gSP|;Gy
xbIxtZm
/* (non-Javadoc) 2lGq6Au:
* @see com.adt.dao.UserDAO#getUserCount() r:u5+A
*/ JK_sl>v.7
publicint getUserCount()throws HibernateException { nOOA5Gz
int count = 0; -8-Aqh8|
String querySentence = "SELECT count(*) FROM GwpJxiFgk
0.?|%;^ib
user in class com.adt.po.User"; FO*Py)/rX
Query query = getSession().createQuery Nf3L
0BD3~Lv
(querySentence); G $?VYC8;
count = ((Integer)query.iterate().next MJK L4 G
JL]6o8x
()).intValue(); *s_)E2
return count; Xh){W~-
} .>&kAf.
u{I)C0
/* (non-Javadoc) B&tl6?7h
* @see com.adt.dao.UserDAO#getUserByPage z7J#1q~:yY
[*,`a]z-Q
(org.flyware.util.page.Page) 27;*6/>,
*/ &!~q#w1W-5
publicList getUserByPage(Page page)throws /VJ[1o^
\5J/?
HibernateException { aG,N>0k8
String querySentence = "FROM user in class NK d8XQ=%
#A?U_32z/2
com.adt.po.User"; a?@j`@]ZR~
Query query = getSession().createQuery *!Xhy87%Z)
iX~V(~v
(querySentence); O"Ar3>
query.setFirstResult(page.getBeginIndex()) 0e3aWn
.setMaxResults(page.getEveryPage()); C#(4>'
return query.list();
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} W<kJ%42^j
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} 3pm;?6i6
" >;},$
#Jg)HU9
A`IE8@&Z'
!30BZM^
至此,一个完整的分页程序完成。前台的只需要调用 K47W7zR
(]rtBeT
userManager.listUser(page)即可得到一个Page对象和结果集对象
%<K`d
c^I_~OwaE
的综合体,而传入的参数page对象则可以由前台传入,如果用 voCQ_~*)9
EpS"NQEe
webwork,甚至可以直接在配置文件中指定。 YwEXTy>0
)x#^fN~ 7`
下面给出一个webwork调用示例: \Z<' u;
java代码: J,k9?nkY /
5^[V%4y>
WG<D+P
/*Created on 2005-6-17*/ y1f&+y9e
package com.adt.action.user; p.&FK'&[0
8L.Y0_x
import java.util.List; ]M>mwnt+
{R]4N]l>
import org.apache.commons.logging.Log; f5^[`b3H
import org.apache.commons.logging.LogFactory; H$WuT;cTE
import org.flyware.util.page.Page; 7 zK%CJ
l[.RnM[v
import com.adt.bo.Result; 6wfCC, 2
import com.adt.service.UserService; i9uJ%nd:
import com.opensymphony.xwork.Action; T[L
aw {?UvL&
/** ho;Km
* @author Joa vfm|?\
*/ pzH N:9r
publicclass ListUser implementsAction{ U!TFFkX[
]xbR:CYJ
privatestaticfinal Log logger = LogFactory.getLog (?D47^F &
b$H{|[
(ListUser.class); 1]m]b4]
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private UserService userService; o%5^dX&[
2t*@P"e!
private Page page; do C8!
>kd&>)9v
privateList users; O8r9&Nv
wSBDJvI
/* SX$v&L<
* (non-Javadoc) c{7!:hi`x
* %5NfF65'
* @see com.opensymphony.xwork.Action#execute() TnCN2#BO
*/ l+Uy
publicString execute()throwsException{ >y
&9!G
Result result = userService.listUser(page); k7W7S`H
page = result.getPage(); X~G!{TT_x6
users = result.getContent(); &%$r3ePwc
return SUCCESS; 2mWW0txil
} _T7tq
wZ5+ H%x
/** |#Z:v1]"
* @return Returns the page. '/J}T -,Z
*/ gyondcF
public Page getPage(){ 1zl6Rwk^o
return page; 4&2aJ_ 2y
} :"#EQq]ct
^?VYE26
/** |Qo;=~7
* @return Returns the users. ^Bf@ I
*/ VZ5EV'D8!
publicList getUsers(){ j
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return users; m$Lq#R={Z
} rfpeX
m(L]R(t
/** LkD$\i
* @param page D9*GS_K2t
* The page to set. 4N|^Joi
*/ M1^,g~e
publicvoid setPage(Page page){ )4vZIU#
this.page = page; 9s8B>(L
} prV:Kq ;O
za`
/** @2yi%_]h
* @param users DJ2EV^D+P
* The users to set. iP6$;Y{ZA
*/ ?kqo~twJ
publicvoid setUsers(List users){ ,W;\6"Iwx'
this.users = users; {L$ ]NQdz
} Kz:g9
5zWxI]4d\
/** }SR}ET&z
* @param userService VImcW;Xa
* The userService to set. X>(?
*/ N{U``LV
publicvoid setUserService(UserService userService){ Xt %;]1n
this.userService = userService; e
"5S;
} wu"6Kyu
} (p08jR
'5
wuSp+?{5k
u=JI 1
RcIGIt
t."hAvRL
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-!Bpr16o0
gJ6C&8tl
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 F:"<4hiA"
a;jXMR
么只需要: /B73|KB+
java代码: _h",,"p#o
g}
7FR({b
sDL@e33Yb
<?xml version="1.0"?> 9tvLj5~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork [XK Ke
TR/'L!EE
1.0//EN" "http://www.opensymphony.com/xwork/xwork- {%.FIw k
n8n(<
1.0.dtd"> tkx1iBW=
Fsv:SL+5
<xwork> c+|,qm
!VUxy
<package name="user" extends="webwork- AQ:cim`
$R4[TQY).!
interceptors"> He^u+N@B
=X6WK7^0
<!-- The default interceptor stack name ?9hw]Q6r}
u;rK.3o
--> uKHkC.g
<default-interceptor-ref GP6-5Y"8
}JyWy_Y
name="myDefaultWebStack"/> + Bk"
khH
|d\rCq >
<action name="listUser" l ps
6lnh
{Hxvt~P
class="com.adt.action.user.ListUser"> O&YX V
<param H. U wM
W|XTa
name="page.everyPage">10</param> E#?*6/
<result S(<r-bV<
%upnXRzw
name="success">/user/user_list.jsp</result> EkS7j>:
</action> hyqsMkW|
!m)P*Lw
</package> >Q':+|K}
jkw:h0hX
</xwork> M il
![A1
+Gv{Apd"
,b!!h]t
=@$G3DM
+^1E0@b%
72@lDY4cE
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 tr3Rn :0]
_X5@%/Vz
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。 9fp@d
2]W"sT[
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 a-w=LpVM
Ba==Ri8$
Gu}
`X23
`|@# ~
A;VjMfoB
我写的一个用于分页的类,用了泛型了,hoho <8#Q5
IH|PdVNtg
java代码: )QS4Z{)U
VbR/k,Co
AY{#!RtV
package com.intokr.util; wT/TQEgz
? ->:,I=<~
import java.util.List; dm;H0v+Y'
J!r,ktO^U?
/** ivL}\~L
* 用于分页的类<br> *{/
ww9fT
* 可以用于传递查询的结果也可以用于传送查询的参数<br> v_-S#(
* wBlfQ
w-N
* @version 0.01 3Jt_=!qlo
* @author cheng \z>Re$:
*/ q0|u vt"
public class Paginator<E> { *K#7,*Oz
privateint count = 0; // 总记录数 r~ gjn`W
privateint p = 1; // 页编号 R'bmE:nL
privateint num = 20; // 每页的记录数 ILdRN
privateList<E> results = null; // 结果 5c50F{
i
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/** Fr{u=0 X
* 结果总数 n^<3E; a
*/ ]C.x8(2!f
publicint getCount(){ :EOx>Pf_9)
return count; ~<b/%l>h1
} O 1TJJ8
f+>l-6M+p
publicvoid setCount(int count){ -1dbJ/)
this.count = count; 5)X;q-
} ZI"L\q=|0#
_-/aMfyQ
/** yU*upQ
* 本结果所在的页码,从1开始 IHqY/ j
* Kjbt1n
* @return Returns the pageNo. eZDqW)x
*/ :B(F?9qK
publicint getP(){ 3I!xa*u
return p; mEi+Tj zp
} &' ,A2iG
m8KJ~02l#
/** A)9[.fhx
* if(p<=0) p=1 *Z0 Y:"
* +Kc1a;
* @param p x1:#rb'
*/ Tj
&PB_v1
publicvoid setP(int p){ biwV7<
if(p <= 0) ~F5JN^5Y
p = 1; [NQ\(VQ1c
this.p = p; 5f+ziiZ
} GA&mM