Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 7=G6ao7
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ,q%X`F
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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 A< .5=E,/
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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 g5U,
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分页支持类: H,
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java代码: uKzx >\}?1
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package com.javaeye.common.util; > 3&
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import java.util.List; F4~OsgZ'N
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publicclass PaginationSupport { 1q;R+65
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publicfinalstaticint PAGESIZE = 30; Z42q}Fhm*R
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privateint pageSize = PAGESIZE; L[PqEN\i
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privateList items; L+ew/I>:
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privateint totalCount; }WJXQ@
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privateint[] indexes = newint[0]; _S[@?]=`b
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privateint startIndex = 0; ommW
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public PaginationSupport(List items, int ThP~k9-
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totalCount){ ]u<U[l-w
setPageSize(PAGESIZE); BO}IN#
setTotalCount(totalCount); EO(l?Fgw]$
setItems(items); Q `K^>L1
setStartIndex(0); -hfDf{QN
} hQ>$"0K
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public PaginationSupport(List items, int k6DJ(.n'%a
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totalCount, int startIndex){ +z9BWo!{I
setPageSize(PAGESIZE); 1c/<2 xO~
setTotalCount(totalCount); "1""1";
setItems(items); wY8Vc"
setStartIndex(startIndex); jCj8XM{c>
} _[8JSw7
iuqJPW^}
public PaginationSupport(List items, int >r)UDa+
;s~xS*(C
totalCount, int pageSize, int startIndex){ ZwxEcs+UM
setPageSize(pageSize); B^M
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setTotalCount(totalCount); R4)l4rnO
setItems(items); wqm{f~nj=
setStartIndex(startIndex); vR#MUKfh
} fWJOP sp*/
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publicList getItems(){ W;yg{y
return items; =}%:4
} aiX4;'$x!
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publicvoid setItems(List items){ 08@4u
L
this.items = items; .rg "(I
} O>f*D+A-
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publicint getPageSize(){ r_ m|?U
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return pageSize; rx]Q,;"
} ku57<kb
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publicvoid setPageSize(int pageSize){ EQ"_kJ>81Y
this.pageSize = pageSize; #WUN=u
} F*z>B >{)
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publicint getTotalCount(){ #6y fIvap
return totalCount; {?w*n_T.
} Ac*)z#H
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publicvoid setTotalCount(int totalCount){ W7s
if(totalCount > 0){ <b4}
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this.totalCount = totalCount; _;x` 6LM
int count = totalCount / aFnyhu&W'
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pageSize; cWQ &zc
if(totalCount % pageSize > 0) ;eFV}DWW
count++; zb~;<:<
indexes = newint[count]; CyVi{"aF3
for(int i = 0; i < count; i++){ MD;,O3Ge
indexes = pageSize * nRHlHu
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i; iN Lt4F[i
} ),o=~,v:
}else{ \/wk!mWV@
this.totalCount = 0; BD.l 5~:
} BB/c5?V
} LEg|R+6E
x
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publicint[] getIndexes(){ ^}gZ+!kA
return indexes; K)Ya%%6[U#
} 55y}t%5
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publicvoid setIndexes(int[] indexes){ 2
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this.indexes = indexes; 0ikA@SAq
} Vw.4;Zy(
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publicint getStartIndex(){ &"1 _n]JO
return startIndex; O#^qd0e'P!
} sV%=z}n=
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publicvoid setStartIndex(int startIndex){ oY\;KPz
if(totalCount <= 0) -G1R><8[
this.startIndex = 0; pP\^bjI
elseif(startIndex >= totalCount) ]]u_Mdk
this.startIndex = indexes rJp9ut'FEz
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[indexes.length - 1]; NP.qh1{NP
elseif(startIndex < 0) 6!U~dt#a
this.startIndex = 0; E_z,%aD[
else{ ! OVi\v
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this.startIndex = indexes je:J`4k$
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[startIndex / pageSize]; &`"uKO]
} =(<7o_gJ
} :h0!giqoQ
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publicint getNextIndex(){ JV;VR9-l
int nextIndex = getStartIndex() + -S@ ys
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pageSize; ]VN1Y)
if(nextIndex >= totalCount) =*?XZA)c
return getStartIndex(); wxG*mOw
else ~ayU\4B
return nextIndex; N9H qFp
} z.t,qi$;{U
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publicint getPreviousIndex(){ X-"0Zc
int previousIndex = getStartIndex() - -zH-9N*c
VM3)L>x]/
pageSize; *:chN' <
if(previousIndex < 0) >u`Ci>tY
return0; _=qk.| p/
else nzB!0U
return previousIndex; {X\FS
} |z)7XK
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} 'Te'wh=Y
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抽象业务类 y0t-e
java代码: 5e'**tbKH
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/** yAJrdY"
* Created on 2005-7-12 UXS+GAWU
*/ f*[Uq0?
package com.javaeye.common.business; cPl$N5/5
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import java.io.Serializable; _ =(v? 2:?
import java.util.List; f./j%R@
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import org.hibernate.Criteria; ub{Yg5{3S\
import org.hibernate.HibernateException; _lOyT$DN
import org.hibernate.Session; T,4REbm^
import org.hibernate.criterion.DetachedCriteria; `7
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import org.hibernate.criterion.Projections; pWGIA6&v(
import WODgG@w
; JHf0
org.springframework.orm.hibernate3.HibernateCallback; )|U+<r<
import XCO;t_%
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org.springframework.orm.hibernate3.support.HibernateDaoS A6F/w
wo ) lkovd
upport; p:4oA<V
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import com.javaeye.common.util.PaginationSupport; Znh<r[p<
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public abstract class AbstractManager extends s9?H#^Y5u
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HibernateDaoSupport { k?Iq 6
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privateboolean cacheQueries = false; u,Cf4H*xS
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privateString queryCacheRegion; Z1+1>|-iW
s !HOrhV
publicvoid setCacheQueries(boolean L q;=UE
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cacheQueries){ Czd)AVK
this.cacheQueries = cacheQueries; %y\
} gs= (h*
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publicvoid setQueryCacheRegion(String O ;B[ZMV
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queryCacheRegion){ 4"%LgV`
this.queryCacheRegion = M[ ,:NE4H
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queryCacheRegion; G+Zm
} ?xCWg.#l4V
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publicvoid save(finalObject entity){ H*EN199
getHibernateTemplate().save(entity); c0:`+>p2
} ,y*|f0&"~
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publicvoid persist(finalObject entity){ >o!~T}J7
getHibernateTemplate().save(entity); J?bx<$C@
} CF@j]I@{
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publicvoid update(finalObject entity){ 2xpI|+a%
getHibernateTemplate().update(entity); |VML.u:N
} HY7#z2L
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publicvoid delete(finalObject entity){ ;[[oZ
getHibernateTemplate().delete(entity); fnU;DS]W
} XXPpj< c
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publicObject load(finalClass entity, 4#wZ#}
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finalSerializable id){ #?RT$L>n
return getHibernateTemplate().load i~EFRI@
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(entity, id); r1[Jo|4vo
} &BJ"T
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publicObject get(finalClass entity, ^1,VvLA+
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finalSerializable id){ `"qSr%|
return getHibernateTemplate().get nHF%PH#|o
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(entity, id); ]*vv=@"`e
} /X97dF)zt
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publicList findAll(finalClass entity){ B)u*c]<qU
return getHibernateTemplate().find("from @ZGD'+zd?
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" + entity.getName()); UrEfFtH'
} Ex$i8fO(
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publicList findByNamedQuery(finalString $~<]G)*Z
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namedQuery){ EHX/XM
return getHibernateTemplate }w/6"MJ[n
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().findByNamedQuery(namedQuery); QlK]2r9
} ~-o[v-\
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publicList findByNamedQuery(finalString query, X_2pC|C
) i=.x+Q
finalObject parameter){ ,FDRU
return getHibernateTemplate
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*'h J5{U
().findByNamedQuery(query, parameter); 6ly`lu9
} R&]#@PW^
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publicList findByNamedQuery(finalString query, w>h\643
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finalObject[] parameters){ %oHK=],|1
return getHibernateTemplate `0Bk@B[>
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().findByNamedQuery(query, parameters); )>U7+ Me
} x /E<@?*:
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publicList find(finalString query){ 9B?-&t
return getHibernateTemplate().find .I
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(query); |58xR.S'g
} B6xM#)
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publicList find(finalString query, finalObject sA!$}W
, IDCbJ
parameter){ =`Lci1#pu}
return getHibernateTemplate().find Dg
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(query, parameter); F;sZc,Y,^
} 1j?+rs+o-
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public PaginationSupport findPageByCriteria /l1OC(hm
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(final DetachedCriteria detachedCriteria){ GYwU3`{
return findPageByCriteria jcL%_of
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); On-zbE
} `R6dnbH
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public PaginationSupport findPageByCriteria z~(3S8$
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(final DetachedCriteria detachedCriteria, finalint z1S
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startIndex){ hU6oWm
return findPageByCriteria iR]K!j2
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(detachedCriteria, PaginationSupport.PAGESIZE, ~EtwX YkRZ
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startIndex); VMIX=gTZ
} 7-#
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public PaginationSupport findPageByCriteria y7~y@ 2
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(final DetachedCriteria detachedCriteria, finalint fs\A(]`$
M`)/^S9
pageSize, c8Je&y8
finalint startIndex){ 1Y'NG<d_
return(PaginationSupport) h5<eU;Rw+
G4]( !f!Kv
getHibernateTemplate().execute(new HibernateCallback(){ h0a|R4J
publicObject doInHibernate D0^h;wJ=4+
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(Session session)throws HibernateException { *WaqNMD[%
Criteria criteria = WT63ve
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detachedCriteria.getExecutableCriteria(session); 5yk#(i7C
int totalCount = ->L> `<7(
LR#BP}\b'
((Integer) criteria.setProjection(Projections.rowCount 'e/wjV
B,A,5SuMk
()).uniqueResult()).intValue(); fLS].b]1N
criteria.setProjection Q>(a JF
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(null);
s>*xAIx
List items = 5Ky(C6E$s
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criteria.setFirstResult(startIndex).setMaxResults z3I
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.tcdqL-'
(pageSize).list(); nO+R>8,Q
PaginationSupport ps = Jb*E6-9G
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new PaginationSupport(items, totalCount, pageSize, VYjt/\Z
{$g3R@f^~
startIndex); {B-*w%}HU
return ps; IGNU_w4j
} )$ M2+_c
}, true); >#VNA^+t
} LwYWgT\e
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public List findAllByCriteria(final 1Li*n6tLX`
R*/s#*gmL
DetachedCriteria detachedCriteria){ F3[,6%4v
return(List) getHibernateTemplate sGa}Cf;H@g
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().execute(new HibernateCallback(){ 3$ wK*xK
publicObject doInHibernate CEW1T_1U<\
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(Session session)throws HibernateException { Y>6N2&Q
Criteria criteria = )2a)$qx;
;5DDV6
detachedCriteria.getExecutableCriteria(session); \PWH(E9
return criteria.list(); ;y_ ]w6|n
} 0SDnMij&bf
}, true); #%EHcgF
} 'o~gT ;T#
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public int getCountByCriteria(final XBoq/kbw!
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DetachedCriteria detachedCriteria){ F1A40h7R$Y
Integer count = (Integer) IC?(F]$%>
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getHibernateTemplate().execute(new HibernateCallback(){ uP+VS>b
publicObject doInHibernate +Qf}&D_
H@1}_d
(Session session)throws HibernateException { |nE4tN#J<
Criteria criteria = /3&MUB*z&y
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detachedCriteria.getExecutableCriteria(session); Re&"Q8I.8
return [Q+k2J_h
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criteria.setProjection(Projections.rowCount 5vg="@O K
sn"z'=ch
()).uniqueResult(); xv&h>GOg
} hD=.rDvO
}, true); |c^ ?tR<
return count.intValue(); 1jej7p>K
} `nKN|6o#x
} )U=]HpuzI
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}Ba_epM
用户在web层构造查询条件detachedCriteria,和可选的 em'ADRxG+
-]+pwZ4g
startIndex,调用业务bean的相应findByCriteria方法,返回一个 "F%JZO51
M~N/er
PaginationSupport的实例ps。 SnR2o3r-Of
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ps.getItems()得到已分页好的结果集 iGkysU<wcp
ps.getIndexes()得到分页索引的数组 le]~Cy0
ps.getTotalCount()得到总结果数 x x4GP2
ps.getStartIndex()当前分页索引 uKXNzz
ps.getNextIndex()下一页索引 nwh @F1|
ps.getPreviousIndex()上一页索引 ^sB0$|DU
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 !1fZ7a
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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 QeG9CS)E}j
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一下代码重构了。 HC/z3b;
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我把原本我的做法也提供出来供大家讨论吧: ~7 U~
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首先,为了实现分页查询,我封装了一个Page类: naW!b&:
java代码: >W;NMcN~
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/*Created on 2005-4-14*/ "X8jpg
package org.flyware.util.page; - X71JU
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/** [IQ|c?DxpL
* @author Joa msM1K1er
* |PlNVd2
*/ Hddc-7s
publicclass Page { ~y2zl
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/** imply if the page has previous page */ c%J6!\
privateboolean hasPrePage; JD~;.3$/k
)muNfs m
/** imply if the page has next page */ "GZieI
D
privateboolean hasNextPage; !~Uj 'w
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/** the number of every page */ 3_~iq>l
privateint everyPage; \7uM5 k}l
lU%}_!tp3/
/** the total page number */ L]|mWyzT
privateint totalPage; :t]HY2
Pps-,*m
/** the number of current page */ {@^;Nw%J
privateint currentPage; B+j]C$8}
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/** the begin index of the records by the current r~lZ8$KC
. \"k49M`
query */ 0{|HRiQH9+
privateint beginIndex; k=hWYe$iAz
8~]D!c8; a
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/** The default constructor */ ||_hET
public Page(){ )&Oc7\J,
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} DS<1"4 b|
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/** construct the page by everyPage >F7w]XH
* @param everyPage `X6JZxGyd
* */ &$F<]]&
public Page(int everyPage){ Jpj=d@Of70
this.everyPage = everyPage; vRmn61
} 3KkfQ{
XiE`_%NW
/** The whole constructor */ t>I.1AS
public Page(boolean hasPrePage, boolean hasNextPage, iqQT ^
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$/++afim
int everyPage, int totalPage, _`|1B$@x
int currentPage, int beginIndex){ d]pb1ECuu
this.hasPrePage = hasPrePage; '7-Yo
Q
this.hasNextPage = hasNextPage; /Vn>(;lo
this.everyPage = everyPage; !Qe;oMqy}
this.totalPage = totalPage; aa`(2%(:
this.currentPage = currentPage; ej`%}e%2
this.beginIndex = beginIndex; ?;XEb\Kf
} t'rN7.d
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/** _\}'5nmw\
* @return d,V#5l-6
* Returns the beginIndex. ,Of^xER`
*/ O1J&Lwpk,
publicint getBeginIndex(){ q8v[u_(yD
return beginIndex; i2~uhGJ
} f"QiVJq
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2&@@<
/** [1VA`:?W
* @param beginIndex 1cLtTE
* The beginIndex to set. d(T4Kd$r
*/ {r,Uik-nL
publicvoid setBeginIndex(int beginIndex){ wA=r]BT
this.beginIndex = beginIndex; G<;~nAo?f0
} $J`O-"M
h:YD$XE
/** 5ilGWkb`'X
* @return N+|NI?R?}
* Returns the currentPage. GM%+yS}(P
*/ }02`ve*
publicint getCurrentPage(){ jwDlz.sW!
return currentPage; 9-KhJq%
} }}AIpYp,P
,c p2Fac
/** I&;>(@K
* @param currentPage .f\LzZ-I:
* The currentPage to set. .Pc>1#z&[
*/ 21uK&nVf^l
publicvoid setCurrentPage(int currentPage){ ~s!Q0G^G
this.currentPage = currentPage; a1U|eLmUb
} M"~jNe|
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/** { mi}3/
* @return ]pax,|+$C
* Returns the everyPage. ef5)z}B
*/ kQ`tY`3F
publicint getEveryPage(){ LKIMT
return everyPage; =3e7n2N)
} "O&93#8
3S0.sU~_U
/** U0~_'&Fe
* @param everyPage ?+yr7_f3*
* The everyPage to set. mmAm@/
*/ _R4}\3}!
publicvoid setEveryPage(int everyPage){ 9%!h/m>rW
this.everyPage = everyPage; [GLH8R
} c/;;zc
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/** )ZG;.j
* @return 3o<d=@`r
* Returns the hasNextPage. )dXa:h0RZ
*/ rf.pT+g.P
publicboolean getHasNextPage(){ \Pg~j\;F]
return hasNextPage; 3nq?Y8yac
} +)Z]<O
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/** |Wh3a#
* @param hasNextPage oaY_6
* The hasNextPage to set. ;O"?6d0
*/ TR"C<&y$j
publicvoid setHasNextPage(boolean hasNextPage){ 3[YG
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this.hasNextPage = hasNextPage; v, $r.g;
} O\5%IfB'"
OxlA)$.hpu
/** d>NGCe
* @return $@g]?*L:
* Returns the hasPrePage. ~6[?=mOi'
*/ ]P4WfV
d
publicboolean getHasPrePage(){ R=D]:u<P
return hasPrePage; Njq}M/{U
} o-,."|6
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/** rPV
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* @param hasPrePage (I[_}l
* The hasPrePage to set. [);oj<
*/ DiC z%'N
publicvoid setHasPrePage(boolean hasPrePage){ H?$dnwR
this.hasPrePage = hasPrePage; xEb>6+-F@
} B=_w9iVN
o`U}uqrO
/** ZlT }cA/n
* @return Returns the totalPage. pu-HEv}]a|
* %b6$N_M{H1
*/ _:x]'w%
publicint getTotalPage(){ 9^gYy&+>6]
return totalPage; E
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} Ss3p6%V/
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/** twT/uBQ4a
* @param totalPage -'rdN i
* The totalPage to set. 3]Z1kB
*/ N5
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publicvoid setTotalPage(int totalPage){ Ltlp9 S
this.totalPage = totalPage; VUb>{&F[
} q6zVu(
GABZsdFZ!
} xL}i9ozZ
w^yb`\$
l45/$G7
]\E"oZ
lZFu|(
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 Q@D7\<t
VtBC~?2U)B
个PageUtil,负责对Page对象进行构造: YIQD9
java代码: d?,'$$ aB
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asWk]jjMG
/*Created on 2005-4-14*/ 222 Y?3>@D
package org.flyware.util.page; :4ryi&Y
}:Z.g
import org.apache.commons.logging.Log; 8-Abg:)
import org.apache.commons.logging.LogFactory; |/Nh#
18&"j 8'm
/** /cjz=r1U>
* @author Joa P/%7kD@5;
* 6h 0qtXn-
*/ _`$Q6!Z)l
publicclass PageUtil { A*JOp8\)
/{T&l*'
privatestaticfinal Log logger = LogFactory.getLog iaGA9l<b
N*Y[[N(
(PageUtil.class); K-qWT7<
u]^s2v
/** qeZG/\,
* Use the origin page to create a new page l:HQ@FX
* @param page aZ#FKp^8H
* @param totalRecords rRTKF0+
* @return |IgR1kp+.
*/ Xp<q`w0I,
publicstatic Page createPage(Page page, int >m%_`68
y>o:5':;'
totalRecords){ UXm_-/&b9
return createPage(page.getEveryPage(), #bOv}1,s
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page.getCurrentPage(), totalRecords); m+QS -woHn
} ]OAU&t{
Z@~gN5@,M
/** Kb~nC6yJc
* the basic page utils not including exception bnxp[Qk|5
1p&.\ ^
handler 5100fX}
* @param everyPage _O`prX.:B0
* @param currentPage ~9 >H(c
* @param totalRecords ) CGQ}
* @return page =RoE=)1&-
*/ `<XS5h
h=
publicstatic Page createPage(int everyPage, int }%g[1
#%(
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currentPage, int totalRecords){ tXE/aY*I
everyPage = getEveryPage(everyPage); xUJ(tG3
currentPage = getCurrentPage(currentPage); E-A9lJWr
int beginIndex = getBeginIndex(everyPage, Gp9 <LB\,
}m:paB"3
currentPage); pb!2G/,.[
int totalPage = getTotalPage(everyPage,
:~-:
>a;a8EA<O
totalRecords); ]LE,4[VxRz
boolean hasNextPage = hasNextPage(currentPage, 1k[_DQ=^l1
Z+xkN
totalPage); z)Rkd0/X
boolean hasPrePage = hasPrePage(currentPage); > ,6
1[P}D~ nQ
returnnew Page(hasPrePage, hasNextPage, pa-*&p
everyPage, totalPage, D#GuF~-F!R
currentPage, R
iZ)FW
GT6; I7
beginIndex); j{C~wy!J
} ib,`0=0= O
6IqPZ{g9K'
privatestaticint getEveryPage(int everyPage){ u`ir(JIj]
return everyPage == 0 ? 10 : everyPage; $z=a+t *
} +3,7 Apj
Th_@'UDa
privatestaticint getCurrentPage(int currentPage){ Agd"m4!
return currentPage == 0 ? 1 : currentPage; p$,7qGST
} {O+T`;=)L
1P)K@j
privatestaticint getBeginIndex(int everyPage, int pH~\~
4LSs WO<@
currentPage){ | W@ ~mrO
return(currentPage - 1) * everyPage; N"9^A^w8k
} tI^91I
8\J$\Edv
privatestaticint getTotalPage(int everyPage, int l;-2hZ
Tzd#!Lvm:,
totalRecords){ ~-"CU:$o
int totalPage = 0; {$S"Sj
r^k+D<k[7
if(totalRecords % everyPage == 0) =Jp:dM*
totalPage = totalRecords / everyPage; O%t? -h
else B:>:$LIL
totalPage = totalRecords / everyPage + 1 ; QPuc{NcB>
O>E}Lu;|
return totalPage; {-)^?Zb
@
} Csyh
'v
,e'r 0
privatestaticboolean hasPrePage(int currentPage){ /#9P0@Y
return currentPage == 1 ? false : true; |=5zI6pT
} 9>{fsy
`;mgJD
privatestaticboolean hasNextPage(int currentPage, m%9Yo%l~
J;sQvPHV8
int totalPage){ 7 [e-3
return currentPage == totalPage || totalPage == NSVE3
" ILF!z
0 ? false : true; Xl=RaV^X"
} $YJ 1P
Mg >%EH/'
P`rfDQoZ
} &D<6Go/)_*
>p&"X 2
@
&5}YTKe}|
]ty$/{hx'
UV(`.
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。 x@X2r
h<L_ =)lH
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 a>C;HO
:@(1~Hm
做法如下: 4EYD5
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 fAh|43Y*a
olv&K(-ccI
的信息,和一个结果集List: iKq_s5|sW
java代码: !S~)U{SSK
D)MFii1J~
(jKqwVs.:
/*Created on 2005-6-13*/ Az8b_:=
package com.adt.bo; K0>;4E>B
;9~YQW@|
import java.util.List; 0L;,\&*u
*mV?_4!,f7
import org.flyware.util.page.Page; [__P-h{J
>QDyG8*
/** IFW(nB(
* @author Joa r@JMf)a]
*/ Zzlt^#KLx
publicclass Result { aj|3(2;Kp
ll}_EUF|
private Page page; :E{)yT
<\nM5-wR
private List content; <j,I@%
eP (*.
/** q AVypP?J
* The default constructor |>P:R4P
*/ [`|t( E'
public Result(){ /#5rt&q
super(); 75>%!mhM
} Y"ta`+VJ
`pv
/** `D3q!e
* The constructor using fields M*'8$|Z
* gHgqElr(
* @param page C{U*{0}
* @param content '`tFZfT
*/ 5xT, O
public Result(Page page, List content){ $[_5:@T%N
this.page = page; <IU
this.content = content; ,or;8aYc#
} [-`s`g-
(4z_2a(Dl,
/** =f@71D1
* @return Returns the content. 2cu2S"r
*/ =H: N!!:
publicList getContent(){ Obu 6k[BE.
return content; =2*2$
} 2K3j3 |T
l _2Xao$
/** &n]v
* @return Returns the page. BZOl&G(
*/ dJzaP
public Page getPage(){ E*R-Dno_F
return page; /0`Eux\
} nYC.zc*o x
bfUKh%!M
/** j*?E~M.'1K
* @param content ?gu!P:lZS
* The content to set. GQ85ykky
*/ EId>%0s5
public void setContent(List content){
"X=^MGV
this.content = content; ZHwl 9n#m
} RK*tZ
1z; !)pG.
/** DZ`,QWuA
* @param page |+~P; fG
* The page to set. O*2{V]Y
@
*/ +-x+c:
IxA
publicvoid setPage(Page page){ .R)Ho4CE
this.page = page; I+Y Z+
} RYl{89
} cEXd#TlY~X
<`q-#-V@
w3iX "w
n\7>_
Z3<lJk\Y
2. 编写业务逻辑接口,并实现它(UserManager, W-D4"
G@
Hl}m*9<9us
UserManagerImpl) g\+!+!"~
java代码: 7h.[eMLPB
iyR5mA
g}?39?o4
/*Created on 2005-7-15*/ 8eCh5*_$
package com.adt.service; amQiH!}8R
'mv|6Y
import net.sf.hibernate.HibernateException; _x-2tnIxXv
D41.$t[
import org.flyware.util.page.Page; }WR@%)7ay
NUBzc'qb
import com.adt.bo.Result; zzC{I@b
/^i_tLgb
/** YY>&R'3[
* @author Joa 17:7w
*/ ?r$&O*;
publicinterface UserManager { T_\hhP~
=%77~q-HL
public Result listUser(Page page)throws eHHU2^I,
<e|B7<.
HibernateException; AgDXpaq
!~m PxGY
} X#W6;?Z\
aTaL|&(
}PMlG
Qc Xw -
'\pSUp
java代码:
1[Q~&QC
W$}2
$}r0U
Kk \,q?
/*Created on 2005-7-15*/ j;_E0j#
package com.adt.service.impl; !}d_$U$
Ngrj@_J
import java.util.List; S>[&]
W
Emh
import net.sf.hibernate.HibernateException; |>JRJ"CFE
U
d+6=Us{
import org.flyware.util.page.Page; U,<?]h
import org.flyware.util.page.PageUtil; q)"yP\
M VE:JNm
import com.adt.bo.Result; #E/|WT
import com.adt.dao.UserDAO; 4SkCV
import com.adt.exception.ObjectNotFoundException; 0sq?>$~Kc*
import com.adt.service.UserManager; Z4k'c+
(>\4%(pnD
/** >(gbUW
* @author Joa B.?@VF
*/ 4E$6&,\
publicclass UserManagerImpl implements UserManager { PTF|"^k+
[L2N[vy;
private UserDAO userDAO; f 0/q{*
_k)EqPYu@
/** }o=s"0 a
* @param userDAO The userDAO to set. `:gXQmt
*/ UE/iq\a>
publicvoid setUserDAO(UserDAO userDAO){ oJc v D
this.userDAO = userDAO; ?,r}@89pY
} ,_'Z Jlx
@
&GA0;q0t
/* (non-Javadoc) ~. 5[
* @see com.adt.service.UserManager#listUser n}J!?zZc
4g+o/+6!4
(org.flyware.util.page.Page) ad<ZdO*h
*/ Xq$9H@.
public Result listUser(Page page)throws D'Kiy
;k=`J
HibernateException, ObjectNotFoundException { !imjfkG
int totalRecords = userDAO.getUserCount(); ?KFj=Yo
if(totalRecords == 0) |v"&Y
throw new ObjectNotFoundException U uSCqI};
opReAU'I
("userNotExist"); g|{Ru
page = PageUtil.createPage(page, totalRecords); .V{y9e+
List users = userDAO.getUserByPage(page); 1VPxCB\
returnnew Result(page, users); *)T7DN8
} hIo^/_K
J)^Kls\>t
} g0s*4E
E`q)vk
fTI~wF8!
kI^Pu
\lpvRZ\L&g
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 kybDw{(}gc
jrO{A3<E
询,接下来编写UserDAO的代码: B5qlU4km&
3. UserDAO 和 UserDAOImpl: Tu=~iQ
java代码: fp$U%uj
%hA0
rW2
/*Created on 2005-7-15*/ ]2mfby
package com.adt.dao; hhJ>>G4R2
:D
import java.util.List; ^}Gu'!z9D
\~:_h#bW
import org.flyware.util.page.Page; X> V`)
!F)BTB7{<
import net.sf.hibernate.HibernateException; K^[Dz\ov5
j'LO'&sQ(
/** @=6$ImU
* @author Joa NvJ}|w,Z
*/ oazy%n(KZ
publicinterface UserDAO extends BaseDAO { q[~+Zm
cx+%lco!
publicList getUserByName(String name)throws TxmKmZ u
RxGZ#!j/
HibernateException; s,8g^aF4
SuJ4)f;'0
publicint getUserCount()throws HibernateException; 8^qLGUxz
Dp;6CGYl?
publicList getUserByPage(Page page)throws oN.#q$\` k
l7S&s&W @
HibernateException; +{&++^(}a
I*=
=I4qx
} z?g\w6
y.WEO>
9y;8JO
}N#hg>;
B
QzD8
jk#
java代码: 'z x1kq1
q=/ck
O.'\GM
/*Created on 2005-7-15*/ x|A{|oFC
package com.adt.dao.impl; 6iJ\7
'n7Ld6%1
import java.util.List; 7HEUmKb"
-h#9sl->
import org.flyware.util.page.Page; lm(k[]@
\']_ y\
import net.sf.hibernate.HibernateException; -hP>;~*4
import net.sf.hibernate.Query; ;c0z6E /
w7Vl,pN,
import com.adt.dao.UserDAO; e~Z>C>J
cy( WD#^
/** Bpdx]5qfK
* @author Joa !WQ S.&
*/ uzaDK
public class UserDAOImpl extends BaseDAOHibernateImpl h$a%PaVf
nCdxn#|
implements UserDAO { Nr0}*8#j
oz/Nx{bg
/* (non-Javadoc) {h}e 9
* @see com.adt.dao.UserDAO#getUserByName Q1u/QA:z7
>WYradLUi
(java.lang.String) 4
JDk()
*/ nB#XQ8Nzx^
publicList getUserByName(String name)throws nrRP1`!]T
;Km74!.e7
HibernateException { f]]UNS$AYQ
String querySentence = "FROM user in class 2sahb#e
)
.L))EB
com.adt.po.User WHERE user.name=:name"; 9\a;75a
Query query = getSession().createQuery "tg?V
pcO0xrI
(querySentence); oC1Nfc+
query.setParameter("name", name);
^#&:-4/
return query.list(); ffoLCx4o0E
} vjO@"2YEw
5YnTGf&
/* (non-Javadoc) Ce!xa\
* @see com.adt.dao.UserDAO#getUserCount() '(yjq<
*/ 05/'qf7P,U
publicint getUserCount()throws HibernateException { E@92hB4D"
int count = 0; z3Q#Wmv2
String querySentence = "SELECT count(*) FROM
@1O.;
W60C$*h
user in class com.adt.po.User"; MXGz_Db4'
Query query = getSession().createQuery &WoS(^
o@A|Lm.
(querySentence); #m36p+U
count = ((Integer)query.iterate().next h][$1b&B
<~R{U>zO
()).intValue(); 0iTh |K0
return count; m}o4Vr;"
} ;]sbz4?
&u~#bDh
/* (non-Javadoc) clO9l=g
* @see com.adt.dao.UserDAO#getUserByPage h!q_''*;
$ {5|{`
(org.flyware.util.page.Page) !ui:0_
*/
<5:`tC2
publicList getUserByPage(Page page)throws Z<@dM2b)
/{*0
\`;
HibernateException { Eao^/MKx-
String querySentence = "FROM user in class [7@9wa1v!
}+ZZO0
com.adt.po.User"; U@<]>.$
Query query = getSession().createQuery U6yZKK
ud:5_*
(querySentence); VDy\2-b8d
query.setFirstResult(page.getBeginIndex()) 'fr~1pmx#3
.setMaxResults(page.getEveryPage()); t p<wMrq<
return query.list(); u#~q86k
} K *xca(6
,7mB`0j>
} n(?BZ'&!O
Gsa~zGN
?5jq)xd2
!pAb+6~T
|.Vs(0O
至此,一个完整的分页程序完成。前台的只需要调用 ]c~W$h+F
,AEaW
userManager.listUser(page)即可得到一个Page对象和结果集对象 k5/W'*P
: XaBCF*
的综合体,而传入的参数page对象则可以由前台传入,如果用 |h* rkLY
b[os0D95
webwork,甚至可以直接在配置文件中指定。 RgTrj
/7jb&f
下面给出一个webwork调用示例: m%)Cw)t
7
java代码: wC`+^>WFo
m)Sdogt_
u;3wg`e
/*Created on 2005-6-17*/ ]x:>!y
package com.adt.action.user; 3T84f[CFJ
br4?_,
import java.util.List; Ic')L*i7O
9L9qLF5 t
import org.apache.commons.logging.Log; g8L{xwx<
import org.apache.commons.logging.LogFactory; ((cRe6
import org.flyware.util.page.Page; W}aCU~
"`Mowp*
import com.adt.bo.Result; 32x[6"T
import com.adt.service.UserService; hG8<@
import com.opensymphony.xwork.Action; lNba[;_
?`T-A\A=
/** ^SC2k LI
* @author Joa q!4eVg*
*/ ;<N%D=;}@
publicclass ListUser implementsAction{ &"'Z)iWm
uN+]q qCf
privatestaticfinal Log logger = LogFactory.getLog "^NsbA+
/lDei}
(ListUser.class); @M&qH[tK-A
DuI>z?bS
private UserService userService; /wT<p
J1g+H2
private Page page; g#b9xTGJ^
r2G38/K
privateList users; Df5!z \dx
#bwGDF
/* #$ooV1E
* (non-Javadoc) gnN"6r1
* vtF|:*h
* @see com.opensymphony.xwork.Action#execute() EaKbG>
*/ ><i: P*ht
publicString execute()throwsException{ iOJ5KXrAO
Result result = userService.listUser(page); 7^W(e s
page = result.getPage(); UAe8Ct=YJ
users = result.getContent(); gAr=fq-|
return SUCCESS; ]8/g[Ii
} 0,5)L\{
R
-OXC;y
/** o1Nfn'!3/>
* @return Returns the page. LDh,!5G-M
*/ }*?,&9/_)
public Page getPage(){ ;LqpX!Pi
f
return page; mnL+@mm
} nZ %%{#T7
zvK'j"Wq=
/** W5,&*mo
* @return Returns the users. xO&qo8*
*/ " 6ScVa5)
publicList getUsers(){ .,F`*JVFq
return users; %ty`Oa2
} 7KL@[
WS//0
/** 6u>]-K5
* @param page K.Tob,5`
* The page to set. i
?PgYk&}
*/ 4 (XV)QR
publicvoid setPage(Page page){ qL4s@<|~
this.page = page; Z rv:uEl
} ,ygUy]
89Ir}bCr
/** :!ablO~
* @param users WG*),P?
* The users to set. ksf6O$
*/ ZI.Czzx\=
publicvoid setUsers(List users){ +Jh1D_+!9
this.users = users; \,ne7G21j
} 0*E_D
Q^bYx (r5w
/** J`[gE`d
* @param userService ]=ADX}
* The userService to set. RT|1M"?$
*/ .$fSWlM;
publicvoid setUserService(UserService userService){ ?Wc+
J4
this.userService = userService; [kf6bf@
} +Fb+dU
} RM;Uq>l
=0az5td
_L+j6N.h1
E0AbVa.
vXm'ARj
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, cn: L]%<
b]
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 }bSDhMV;
c
h}wXn
么只需要: Q5lt[2Zyzd
java代码: ;Yt+{pI
%JgdLnQE
\)?+6D'#
<?xml version="1.0"?> )-0+O=v
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork /_qHF-
#Vu;R5GZ}
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 1'N<ITb
C]Y%dQh+a
1.0.dtd"> %o5'M^U
iI>7I<_
<xwork> =3ovaP
9khMG$
<package name="user" extends="webwork- [(eX\kL
f `D(V-4
interceptors"> 70'gVCb
_xmQGX!|
<!-- The default interceptor stack name `NTtw;%Y
uW
[yNwM
--> 3b|=V
<default-interceptor-ref Gu@C*.jj!
E*h!{)z@F
name="myDefaultWebStack"/> YmpaLZJ
JfY(};&
<action name="listUser" S'\e"w
Np i)R)
class="com.adt.action.user.ListUser"> =?Ui(?tI
<param Kv2S&P|jXM
YUHiD*
name="page.everyPage">10</param> SU1N*k#-o
<result ?4oP=.
vZW[y5
name="success">/user/user_list.jsp</result> 8+J>jZ
</action> I\x9xJ4x
684d&\(s
</package> [:(/cKo
ALV(fv$cD
</xwork> ,i1BoG
&=MVX>[
N:+)6a
\|6VGh \Z
{o 2 qY|S
H>W8F2VT
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 fERO(o
Xhq6l3 M
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 M9""(`U
T9XUNR{&
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 .xuzu#-
jRd$Vt
#lg R"%
$wi4cHh
_6V1oe2
我写的一个用于分页的类,用了泛型了,hoho iEZ+Znon
m[KmXPFht1
java代码: JXMH7
lx=tOfj8
]%y>l j?Y
package com.intokr.util;
46pR!k
7~F~ 'V
import java.util.List; xQ7U$QF|]
"l9aBBiu
/** :o .+<_&
* 用于分页的类<br> =JW-EQ6[T
* 可以用于传递查询的结果也可以用于传送查询的参数<br> N'WC!K.e
* &^#u=w?^x
* @version 0.01 o<%0|n_O&
* @author cheng 9^ZtbmUf
*/ EwX{i}j_V
public class Paginator<E> { w]yVNB
privateint count = 0; // 总记录数 B~7!v${
privateint p = 1; // 页编号 oda,
privateint num = 20; // 每页的记录数 KbtV>
privateList<E> results = null; // 结果 dzBP<Xyh
&b`W<PAc?4
/** D4,>g )B
* 结果总数 #CaPj:>[
*/ DJ@n$G`^^
publicint getCount(){ (S?Y3l|
return count; 5QLK
} as!a!1
F -,chp
publicvoid setCount(int count){ ,aLwOmO
this.count = count;
q:TNf\/o
} pm ,xGo2
8\!E )M|4
/** BjsT 9?6W/
* 本结果所在的页码,从1开始 xE
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* Pv/v=s>X
* @return Returns the pageNo. bY=[ USgps
*/ R-j*fO}
publicint getP(){ GPK\nz}
return p; 1*Pxndt&
} |[IyqWG9
C_kuW+H
/** } P ,"
* if(p<=0) p=1 z&tC5]#
* @;tfHoXD
* @param p (=Cb)/s0
*/ T" W<l4i-
publicvoid setP(int p){ +IWH7 qRtp
if(p <= 0) #YYJ4^":k
p = 1; ~cCMLK em
this.p = p; @)uV Fw"\
} twq~.:<o
jh)@3c
/** (+epRC
* 每页记录数量 7!pKlmQ
*/ ZQ_6I}i")
publicint getNum(){ ~}}<+ JEEO
return num; :86:U 0^
} nYjrEy)Q
#%\0][Xf
/** X!ruQem /
* if(num<1) num=1 jRg
gj`o
*/ 3WJk04r
publicvoid setNum(int num){ =+Fb\HvX{
if(num < 1) %7)TiT4V
num = 1; 3X`9&0:j%
this.num = num; v}6iI}r
} G/<zd)
#BUq;5
/** 7TMq#Pb
* 获得总页数 oNAnJ+_
*/ igfQ,LWe!
publicint getPageNum(){ |(z{)yWbC[
return(count - 1) / num + 1; &,k!,<IF
} M`H#Qo5/
p)yP_P
/** heCM+=#~
* 获得本页的开始编号,为 (p-1)*num+1 .Q,"gsY
*/ \D? '.Wo%
publicint getStart(){ FnA Kfh(
return(p - 1) * num + 1; 6M*z`B{hV
} q>.7VN[
vE
M\C9^DX{
/** Nrr})
g
* @return Returns the results. Ak9{P`
*/ M?eP1v:<+G
publicList<E> getResults(){ e$Ds2%SaT
return results; j8`
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} FBNLszT{L
9{jMO
public void setResults(List<E> results){ +Y sGH~jX
this.results = results; (@+pz/
} t<p#u=jOa
't5ufAT
public String toString(){ #cfiN b}GX
StringBuilder buff = new StringBuilder ;\mX=S|a
)=[\Yf K
(); T(D6'm:X
buff.append("{"); @(sz "
buff.append("count:").append(count); l/'GbuECm
buff.append(",p:").append(p); f=F:Af!
buff.append(",nump:").append(num); a|7C6#iz$
buff.append(",results:").append
/:4J
@.eN+o9|
(results); @ep.wW
buff.append("}"); Jw;~ $
return buff.toString(); @*YF!LdU{M
} 5E'/8xp bB
D$}8GYq
} 2X@9o4_4q
c| ^I}
SsZC g#i