Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 c u:1|gt
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 B!X;T9^d
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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 V \4zK$]
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 [ _Nw5_
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分页支持类: R3,O;9i
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java代码: ~[H+,+XLY+
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package com.javaeye.common.util; d=~-8]%\
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import java.util.List; o{n)w6P{R,
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publicclass PaginationSupport { M}cgVMW
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publicfinalstaticint PAGESIZE = 30; EJ&aT etQ
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privateint pageSize = PAGESIZE; l]wjH5mz=i
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privateList items; W7 iml|WV0
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privateint totalCount; 5OS|Vp||b
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privateint[] indexes = newint[0]; 45+w)Vf!
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privateint startIndex = 0; 9PZY](/
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public PaginationSupport(List items, int WBIJ9e2~
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totalCount){ 93+p~?
setPageSize(PAGESIZE); ZM$}Xy\9
setTotalCount(totalCount); .PHz
setItems(items); sb^%eUU])
setStartIndex(0); XC NM
} @2HNYW)
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public PaginationSupport(List items, int KTzkJx
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totalCount, int startIndex){ =^L?Sgg
setPageSize(PAGESIZE); pl.D
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setTotalCount(totalCount); g*uo2-MN&e
setItems(items); =%UX"K`
setStartIndex(startIndex); :kMEL*
} QL{{GQ_dn
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public PaginationSupport(List items, int \KpSYX1
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totalCount, int pageSize, int startIndex){ a`:ag~op@&
setPageSize(pageSize); 1`;,_>8
setTotalCount(totalCount); TGe)%jZ
setItems(items); 9N?BWv}
setStartIndex(startIndex); K.{:H4_
} {Al}a`da
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publicList getItems(){ $cUTe
return items; k&kx%skz
} 5m e|dvk
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publicvoid setItems(List items){ /%'>?8/
this.items = items; MK*WStY
} ^9 g+\W
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publicint getPageSize(){ f T&>L
return pageSize; .gPXW=r
} AZi|85rN
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publicvoid setPageSize(int pageSize){ 13X0LN
this.pageSize = pageSize; @H?_x/qBT
} #t^y$9^
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publicint getTotalCount(){ ^JKV~+ Q
return totalCount; T==(Pw7R7
} 0."TSe83\
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publicvoid setTotalCount(int totalCount){ [J6*Q9B<V&
if(totalCount > 0){ )kq3q5*_
this.totalCount = totalCount; b.<>CG'
int count = totalCount / BgzER[g|q{
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pageSize; x9c/;Q&m
if(totalCount % pageSize > 0) -}h+hS50F
count++; 2I2#o9(Ar
indexes = newint[count]; (($"XOU
for(int i = 0; i < count; i++){ c]y"5;V8
indexes = pageSize * u)DhkF|
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i; j70]2NgX
} ;U
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}else{ T%%+v#+
this.totalCount = 0; kg>Ymo.
} b :Knc$
} Pmj]"7Vd[
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publicint[] getIndexes(){ Llf |fayq
return indexes; *mc]Oa
} y11/:|
Qo4+=^(
publicvoid setIndexes(int[] indexes){ S_z}h
this.indexes = indexes; &IQp&
} yMQuM:d
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publicint getStartIndex(){ 6~
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return startIndex; q/o|uAq
} 5aF03+ko
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publicvoid setStartIndex(int startIndex){ 0 L34)W
if(totalCount <= 0) Y4%Bx8
this.startIndex = 0; 9I a4PPEH1
elseif(startIndex >= totalCount) }),tk?\
this.startIndex = indexes xZ51iD$
TK )Kq
[indexes.length - 1]; qsB,yckml
elseif(startIndex < 0) _]"5]c&*3
this.startIndex = 0; FtUO gL)|
else{ RLypWjMx$
this.startIndex = indexes rf+'U9
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[startIndex / pageSize]; }lzyl*.
} Hev S}L
} :*bmc /c
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publicint getNextIndex(){ 4:\s.Z{!3
int nextIndex = getStartIndex() + ^A8'YTl
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pageSize; pV#~$e
if(nextIndex >= totalCount) }]pq&v!
return getStartIndex(); tJ>OZ
else ,}!OJyT
return nextIndex; ^h+<Q%'a'
} D nA}!s
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publicint getPreviousIndex(){ vUGEzC M
int previousIndex = getStartIndex() - "5mdq-h(
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pageSize; =J0X{Ovn4z
if(previousIndex < 0) UV%Al)3
return0; 'CT8vt;
else D6,rb 9
return previousIndex; 5Sd+Cc
} ,?GEL>F
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} R07Kure
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抽象业务类 $m`?x5rL8
java代码: 6[kp#
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/** * B!uYP
* Created on 2005-7-12 4I7}
*/ V`Z-m-V~1
package com.javaeye.common.business; >3V{I'^^-
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import java.io.Serializable; M]YK]VyG
import java.util.List; 42aYM!
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import org.hibernate.Criteria; y^:!]-+
import org.hibernate.HibernateException; <A +VS
import org.hibernate.Session; Tj}H3/2
import org.hibernate.criterion.DetachedCriteria; ~"89NVk"
import org.hibernate.criterion.Projections; T+7O+X#
import 8KRm>-H)
b: UTq
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org.springframework.orm.hibernate3.HibernateCallback;
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import H%`Ja('"p
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org.springframework.orm.hibernate3.support.HibernateDaoS F$P8"q+
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upport; 5q<AMg
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import com.javaeye.common.util.PaginationSupport; jovI8Dw
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public abstract class AbstractManager extends T)J=lw
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HibernateDaoSupport { (055>D6
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privateboolean cacheQueries = false; };"-6e/9
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privateString queryCacheRegion; f
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publicvoid setCacheQueries(boolean SoX\S|}%6[
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cacheQueries){ k^B<t'
this.cacheQueries = cacheQueries; ?5(Cwy ?
} OKs1irt5
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publicvoid setQueryCacheRegion(String <7-:flQz~
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queryCacheRegion){ EaaLN<i@0
this.queryCacheRegion = j4h6p(w{
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queryCacheRegion; Dy`;]-b6u
} Kx,#Wg{H
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publicvoid save(finalObject entity){ 6U|An*
getHibernateTemplate().save(entity); [\eh$r\
} OolYQU1_
j4pxu/2
publicvoid persist(finalObject entity){ }ZaZPB/_}P
getHibernateTemplate().save(entity); yOHVL~F
} `5da
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publicvoid update(finalObject entity){ (55k70>i3
getHibernateTemplate().update(entity); gEr@L
} >Pa&f20Hp
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publicvoid delete(finalObject entity){ miWog 8j
getHibernateTemplate().delete(entity); "u29| OY
} v+\&8)W=
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publicObject load(finalClass entity, 2z*EamF
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finalSerializable id){ >#pZ`oPEAv
return getHibernateTemplate().load #R^^XG`1
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(entity, id); )?d(7d-l
} mf4C68DI@u
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publicObject get(finalClass entity, 6l Suzu
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finalSerializable id){ Twq/Y07M
return getHibernateTemplate().get `IC2}IiF
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(entity, id); T( LlNq
} <PMQ$s>KK
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publicList findAll(finalClass entity){ kH4xP3. i
return getHibernateTemplate().find("from ;q5.\m:
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" + entity.getName()); I
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} 1iLrKA
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publicList findByNamedQuery(finalString J?y0RX
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namedQuery){ *@+E82D
return getHibernateTemplate >U7{EfUJdx
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().findByNamedQuery(namedQuery); q$iGeE#
} ,#V}qSKUS
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publicList findByNamedQuery(finalString query, 7gnrLc$]O
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finalObject parameter){ bI?uV;m>
return getHibernateTemplate "h\ (a<
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().findByNamedQuery(query, parameter); `zoC++hx
} _Dq,\}
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publicList findByNamedQuery(finalString query, /:GeXDJw
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finalObject[] parameters){ O[<YYL0
return getHibernateTemplate YQ$Wif:@(n
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().findByNamedQuery(query, parameters); E{8-VmY
} Dkyw3*LCn%
Eb~e=){
publicList find(finalString query){ s2kom)
return getHibernateTemplate().find hd%O\D?
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(query); +@mgb4_
} L (@".{T
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publicList find(finalString query, finalObject ]w/%>
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parameter){ 6` 4,
return getHibernateTemplate().find MZWicfUy
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(query, parameter); L7"B`oa(p
} L43]0k
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public PaginationSupport findPageByCriteria 8S#TOeQ
c 4
bo
(final DetachedCriteria detachedCriteria){ h=o%\F4
return findPageByCriteria Xf6\{
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); YgR}y+q^6
} zL=PxFw0
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public PaginationSupport findPageByCriteria W%P$$x5&
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(final DetachedCriteria detachedCriteria, finalint r 3FUddF'
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startIndex){ Z@gEJ^"yA"
return findPageByCriteria ?F^O7\rw
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(detachedCriteria, PaginationSupport.PAGESIZE, F-GrQd:O=
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startIndex); Noi+mL
} !)HB+yr
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public PaginationSupport findPageByCriteria ]EfM;'j[
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(final DetachedCriteria detachedCriteria, finalint O`TM}
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pageSize, f"aqg/l
finalint startIndex){ ;t\C!A6
return(PaginationSupport) D[Kq`
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getHibernateTemplate().execute(new HibernateCallback(){ :89AYqT"
publicObject doInHibernate W;QU6z>
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(Session session)throws HibernateException { Z ItS(oJ.
Criteria criteria = |*JMCI@Mz
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detachedCriteria.getExecutableCriteria(session); @%gth@8
int totalCount = yv2wQ_({
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((Integer) criteria.setProjection(Projections.rowCount Wq"^ {
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()).uniqueResult()).intValue(); 3)_(t.$D
criteria.setProjection M&5De{LS}
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(null); nD}CQ_C
List items = 6GsB*hW
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criteria.setFirstResult(startIndex).setMaxResults j7
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(pageSize).list(); 8=WX`*-uH
PaginationSupport ps = x2Dg92
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new PaginationSupport(items, totalCount, pageSize, [f#7~
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startIndex); sg8j}^VI
return ps; "q3W&@
} xAu&O\V
}, true); .aD=d\
} ?.6fVSa
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public List findAllByCriteria(final _7N^<'B
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DetachedCriteria detachedCriteria){ !"s~dL,7
return(List) getHibernateTemplate OJXK]dZ
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().execute(new HibernateCallback(){ ]Aa.=
publicObject doInHibernate V[avV*;3i
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(Session session)throws HibernateException { mecm,xwm
Criteria criteria = IpKpj"eoLy
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detachedCriteria.getExecutableCriteria(session); fe+2U|y
return criteria.list(); Ue!~|:
} G\/7V L
}, true); N\W4LO6
} T )"Uq
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public int getCountByCriteria(final <BhNmEo)2
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DetachedCriteria detachedCriteria){ i3U_G^8
Integer count = (Integer) +~!\;71:f
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getHibernateTemplate().execute(new HibernateCallback(){ Qcs>BOV~
publicObject doInHibernate 0/,Dy2h
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(Session session)throws HibernateException { &v.Nj9{zi
Criteria criteria = Uq:CM6q\
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detachedCriteria.getExecutableCriteria(session); :2E?|}`7\
return JQk][3Rv
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criteria.setProjection(Projections.rowCount 7f#r&~=
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()).uniqueResult(); ]2@g 5H}M
} CyV(+KBe_
}, true); ~#nbD-*#
return count.intValue(); FiW>kTM8
} )sG/H8
} Nk@a g)
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用户在web层构造查询条件detachedCriteria,和可选的 t+%tN^87:
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 J>%uak<
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PaginationSupport的实例ps。 tk~<tqMq
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ps.getItems()得到已分页好的结果集 j
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ps.getIndexes()得到分页索引的数组 >cRE$d?
ps.getTotalCount()得到总结果数 wxIWh>pZa
ps.getStartIndex()当前分页索引 ZDt|g^
ps.getNextIndex()下一页索引 s7G!4en
ps.getPreviousIndex()上一页索引 4}MZB*);0
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ra>jVE0`
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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
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一下代码重构了。 }`*DMI;-
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我把原本我的做法也提供出来供大家讨论吧: 0DgEOW9H
j%@wQVxq
首先,为了实现分页查询,我封装了一个Page类: @>4=}z_e
java代码: 0Er;l|
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/*Created on 2005-4-14*/ 4E~!$Ustx
package org.flyware.util.page; cO^}A(Ma(
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/** R#w9%+
* @author Joa 'H.,S_v1x
* . L'eVLQe
*/ fx`oe
publicclass Page { \qB:z7I2
OZed+t=
/** imply if the page has previous page */ %jRqrICd
privateboolean hasPrePage; B`1"4[{
"E/UNE6P4
/** imply if the page has next page */ ,s.{R
privateboolean hasNextPage; ];VJ54
,[t>N>10TH
/** the number of every page */ - BE.a<
privateint everyPage; Sm(t"#dp
s!Y`1h{
/** the total page number */ $`O%bsjX
privateint totalPage; 0 CFON2I
p@Ng.HE
/** the number of current page */ q;0QI{:5v
privateint currentPage; ;&8
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/** the begin index of the records by the current 01;
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query */ oGa8#>
privateint beginIndex; bL9EX$P
="Sa>-do,
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/** The default constructor */ 7B|
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public Page(){ Fo86WP}
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} dX8N7{"[
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/** construct the page by everyPage 4EtP|
* @param everyPage JVx
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* */ S85}&\m&4
public Page(int everyPage){ )of?!>'S[
this.everyPage = everyPage; gk.c"$2
} _Boe"
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/** The whole constructor */ L
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public Page(boolean hasPrePage, boolean hasNextPage, 0-!K@#$>=
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int everyPage, int totalPage, wf[B -2q)
int currentPage, int beginIndex){ gfW8s+
this.hasPrePage = hasPrePage; ("
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this.hasNextPage = hasNextPage; M]JD(
this.everyPage = everyPage; 6IyD7PQ
this.totalPage = totalPage; dLq)Z*r
this.currentPage = currentPage; q=H
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this.beginIndex = beginIndex; $%ts#56*
} ;E{k+vkqy
!qjIhZi
/** ">LX>uYmX-
* @return (E.,kcAJ
* Returns the beginIndex. (g8<"<
N?
*/ <E`Ygac
publicint getBeginIndex(){ vg6'^5S7
return beginIndex; G?t<4MTv
} _ 3l ci
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/** \ $PB~-Z
* @param beginIndex 8LMO2Wyq
* The beginIndex to set. 37SbF,G
*/ 1oSrhUTy
publicvoid setBeginIndex(int beginIndex){ H(~:Ajj+zQ
this.beginIndex = beginIndex; DnZkZ;E/
} G; *jL4
N5SePA\ ,?
/** T|{1,wP
* @return &H`A S6
* Returns the currentPage. "Y>
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*/ %%dQIlF
publicint getCurrentPage(){ /2n-q_
return currentPage; *QIlh""6
} 1zDat@<H
1@}`dc
/** %rmn+L),;
* @param currentPage *&d>Vk."]
* The currentPage to set. bAsoIra
*/ ey~5DY7
publicvoid setCurrentPage(int currentPage){ w'/Mn+
this.currentPage = currentPage; oVK3=m@{
} }KBz8M5
#c?xJ&bh
/** ( 2oP=9m
* @return Qrnc;H9)
* Returns the everyPage. {c;][>l
*/ gtV^6(Y
publicint getEveryPage(){ 3($ cBC
return everyPage; V?.')?'V
} 907N;r
.}wVM`81z
/** mO6rj=L^
* @param everyPage I:ag}L8`
* The everyPage to set. R-~ZvVw7L
*/ '\MYC8"
publicvoid setEveryPage(int everyPage){ Ly7|:IbC
this.everyPage = everyPage; cILI%W1
} V+A9.KoI
!>,\KxnM
/** )\qA[rTG
* @return ;yvx -
* Returns the hasNextPage. Q1A_hW2 x
*/ Z8 X=Md8=
publicboolean getHasNextPage(){ b.LMJ'1
return hasNextPage; {Tps3{|wt
} &y7<h>z
hnk,U:7}
/** BrHw02G
* @param hasNextPage Q|DVB
* The hasNextPage to set. }f~:>N#
*/ n0ZrgTVJ
publicvoid setHasNextPage(boolean hasNextPage){ wNk 0F7Ck
this.hasNextPage = hasNextPage; o#D;H[' A
} IzuYkl}
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/** A>?_\<Gp
* @return >{v,HOxl
* Returns the hasPrePage. Rz #&v
*/ ]#7{x
publicboolean getHasPrePage(){ ($h`Y;4
return hasPrePage; vuNt+
} yGxAur=dE
@PaOQ@
/** )U?5O$M;lE
* @param hasPrePage
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* The hasPrePage to set. R2e":`0I
*/ }MCh$
publicvoid setHasPrePage(boolean hasPrePage){ ]g3RVA%\l
this.hasPrePage = hasPrePage; +E7Os|m
} <-]qU}-
7gk}f%,3P
/** V,*<E &+
* @return Returns the totalPage. S`\03(zDA
* $ouw*|<
*/ =o!1}'1 }}
publicint getTotalPage(){ I*SrKZb
return totalPage; @MoBR.
} j_\?ampF
AgBXB%).
/** KkIgyLM
* @param totalPage YUGEGXw
* The totalPage to set. Ue=Je~Ri;9
*/ *K57($F
publicvoid setTotalPage(int totalPage){ $$5E+UDOs
this.totalPage = totalPage; v>[U*E
} S.I3m-
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} >, 9R :X(
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r'bPSu,
YcmLc)a7
XHh!Q0v;
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 ~0 PR>QJ
Qms,kX
个PageUtil,负责对Page对象进行构造: EL$"/ptE
java代码: Zw`9B
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/*Created on 2005-4-14*/ Fs3rsig
package org.flyware.util.page; O6[4=4L
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import org.apache.commons.logging.Log; QyEGK
import org.apache.commons.logging.LogFactory; SJJ[y"GvD
;k=&ZV
/** )ZQ>h{}D
* @author Joa v]?zG&Jh
* XzD+#+By
*/ wyi%!H
publicclass PageUtil { uE]Z,`e
_no;B_m~
privatestaticfinal Log logger = LogFactory.getLog >* )fmfY
0^m`jD
(PageUtil.class); GL^84[f-T
0zHMtC1,
/** 0|=,!sY
* Use the origin page to create a new page _pN:p7l(
* @param page DfsPg':z
* @param totalRecords ;]PP+h
* @return ^D5+S`V
*/ QUO'{;,
publicstatic Page createPage(Page page, int xo.k:F
Q|7$SS6$
totalRecords){ y7ZYo7avg
return createPage(page.getEveryPage(), ?glK~G!i
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page.getCurrentPage(), totalRecords); :AYhBhitC
} /Pyj|!C3`q
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/** %Ek!3t
* the basic page utils not including exception [q!/YL3%
%nV6#pr
handler wsEOcaie
* @param everyPage 53<.Knw5a
* @param currentPage \n>7T*iM&
* @param totalRecords /iw$\F |8
* @return page eD,'M
*/ <5]ufv
publicstatic Page createPage(int everyPage, int [aF"5G
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currentPage, int totalRecords){ %
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everyPage = getEveryPage(everyPage); bamQ]>0|>!
currentPage = getCurrentPage(currentPage); Q.MbzSgXL
int beginIndex = getBeginIndex(everyPage, 1'YUK"i
.2{*>Dzi
currentPage); c\le8C3
int totalPage = getTotalPage(everyPage, ufn%sA
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totalRecords); ^ u:bgwP
boolean hasNextPage = hasNextPage(currentPage, 9U4 D$M
U62Z ?nge%
totalPage); `>Ms7G9S~e
boolean hasPrePage = hasPrePage(currentPage); @gnLY
2 -pv
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returnnew Page(hasPrePage, hasNextPage, KsSIX
everyPage, totalPage, @+7CfvM
currentPage, 0WSOA[R%[b
"9X1T]
beginIndex); )W/_2Q.
} &Lbh?C
UB,0c)
privatestaticint getEveryPage(int everyPage){ U'LPaf$O
return everyPage == 0 ? 10 : everyPage; vcC"
} ~5o2jTNy`p
%uz6iQaq]X
privatestaticint getCurrentPage(int currentPage){ 5VSc5*[
return currentPage == 0 ? 1 : currentPage; ~7wLnB
} .#}A/V.-Y
c"diNbm[
privatestaticint getBeginIndex(int everyPage, int H5(:1
+45.fo
currentPage){ I23"DBR3
return(currentPage - 1) * everyPage; A_Y5{6@
} aMJJ|iiU
c-* *~tb(
privatestaticint getTotalPage(int everyPage, int 88VI
_<
Pa'N)s<
totalRecords){ zeD=-3
int totalPage = 0; :Bi 4z(
Gi\Z"MiBZ
if(totalRecords % everyPage == 0) {^?:- #~h
totalPage = totalRecords / everyPage; d~q7!
else X!6$<8+1OV
totalPage = totalRecords / everyPage + 1 ; %<|cWYM="z
-^JPY)\R
return totalPage; (
6ucA
} kDG?/j90D
j_.tg7X
privatestaticboolean hasPrePage(int currentPage){ T^ - - :1
return currentPage == 1 ? false : true; &\
K
} +LlAGg]Z
]GDjR'[z
privatestaticboolean hasNextPage(int currentPage, )"](?V
Z&n#*rQ7[
int totalPage){ m95]
z18T'
return currentPage == totalPage || totalPage == o(C;;C(*{
})j N
8px
0 ? false : true;
`)>}b 3
} .LGA0
)6%a9&~H
Gr'|nR8
} )2
b-3lz
yH9&HFDp
CSH*^nk':O
FD5OO;$
nd[Ja_h
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。 [
~kS)
8T8]g M
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 1k`gr&S
Tfx-h)oP3
做法如下: a*t>Ks'C
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 4y!GFhMh
}*b\=AS=
的信息,和一个结果集List: h
gu\~}kD
java代码: 3S1{r
)[j
~%h&ELSw
0Hx'C^m72
/*Created on 2005-6-13*/ ZZ/k7(8
package com.adt.bo; w_DaldK*
7`e<H 8g
import java.util.List; p.H`lbVY
7I*rtc&Kb
import org.flyware.util.page.Page; 9i
D&y)$"
yZ]?-7
/** Asy2jw\V
* @author Joa k5*Z@a
*/ $ab{GxmX'4
publicclass Result { H%Z;Yt8^gt
YN~1.!F
private Page page; Ocz21gl-?`
_Fe=:q
private List content; ]:m4~0^#-(
GIfs]zVr`
/** J%
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* The default constructor G_5w5dbG
*/ 4G hg~0
public Result(){ G&`5o*).bb
super(); eu?P6>urA
} s>[Oe|`
%d<UMbS^
/** ~#)9Kl7<X
* The constructor using fields 19RbIG/X
* ;F"Tu
* @param page vl?fCO
* @param content = )4bf"~8
*/ qD/h/
public Result(Page page, List content){ _Y$v=!fY&
this.page = page; %e_){28 n
this.content = content; }=.C~f]A
} [?(qhp!
L X #.
/** 2vddx<&
* @return Returns the content. \jS^+Xf?^
*/ s?fEorG
publicList getContent(){ 1v<uA9A%[
return content; {7q8@`Oa
} gKgdu($NJ
Q5IN1
^=HF
/** RB;2
* @return Returns the page. AJ6O>Euq
*/ ]iZ-MG)J
public Page getPage(){ buWF6LFC
return page; y+izC+
} <l>L8{-3
ZS@R ?
/** vkW;qt}yO
* @param content KqNsCT+j
* The content to set. ZW
5FL-I
*/ A-eCc#I
public void setContent(List content){ B*^QTJ
this.content = content; Hl8\*#;C&>
} 2%MS$Fto
n:Dr< q.
/** E.^u:0:P
* @param page XHY,;4
* The page to set. Ppx 4#j
*/ "tj]mij2)G
publicvoid setPage(Page page){ ~c\2'
this.page = page; Qr?(2t#
} )Rj?\ZUR
} t3!~=U
5o0H7k]
u0$}VO5/a
lO}I>yo}\
T'N/A9{q
2. 编写业务逻辑接口,并实现它(UserManager, 4*UKR!sr
7qdB
UserManagerImpl) 9v7}[`^
java代码: K=dG-+B~}
,rhNXx
xDmwiVy
/*Created on 2005-7-15*/ NF7+Gp6?q
package com.adt.service; ,~NJ}4wP
@X_)%Y-^O
import net.sf.hibernate.HibernateException; !ed0
p
>nKNd_aQ
import org.flyware.util.page.Page; xB}B1H%
h6D1uM"o
import com.adt.bo.Result; \u 6/nvZ]N
=z}M(<G
/** 2JHV*/Q
* @author Joa Qr~yHFc1y
*/ rwAycW7
publicinterface UserManager { >a: 6umY
0'R}'
public Result listUser(Page page)throws IY|>'}UU#
`V?NS,@$
HibernateException;
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u/5)Yx+5_
} O{=@c96rl
yuF\YOA9
H8!lSRq
Wk]E6yz6
dewN\
java代码: [ _&z+
<{.pYrn
!:1BuiL
/*Created on 2005-7-15*/ qn `
\g
package com.adt.service.impl; p%e/>N.P
uHyc7^X>
import java.util.List; n5?7iU&JIo
{z8wFL\
import net.sf.hibernate.HibernateException; /qXP\ a
<J^94-[CF
import org.flyware.util.page.Page; 0Y*Ag,S
import org.flyware.util.page.PageUtil; 3:gF4(.
e{*z4q1
import com.adt.bo.Result; #M:Vwn
JX
import com.adt.dao.UserDAO; 0JLQ.%_
import com.adt.exception.ObjectNotFoundException; <J!?eH9f
import com.adt.service.UserManager; +<c(;Ucl?
"%+9p6/
/** v79\(BX
* @author Joa 8jgamG
*/ x c$jG?83#
publicclass UserManagerImpl implements UserManager { CSMx]jbb
YHo*IX')C?
private UserDAO userDAO; N1'$;9 c
D;X/7 p|>
/** E^V4O l<
* @param userDAO The userDAO to set. Mog!pmc{
*/ 6/L34VH
publicvoid setUserDAO(UserDAO userDAO){ 79ZYRm2;
this.userDAO = userDAO; [L>AU;
:
} =2, iNn
ef
-PlGn
/* (non-Javadoc) 4NmLbM&C8
* @see com.adt.service.UserManager#listUser _U%2J4T2
6"jV>CNc@
(org.flyware.util.page.Page) lhJZPnx~
*/ p}-B>v
public Result listUser(Page page)throws +rOd0?
+L#Q3}=s
HibernateException, ObjectNotFoundException { =' #yG(h
int totalRecords = userDAO.getUserCount(); qbQH1<yS<
if(totalRecords == 0) >/DlxYG?
throw new ObjectNotFoundException jftf]n&Z(q
b`DPf@p^kc
("userNotExist"); Lz}mz-N
page = PageUtil.createPage(page, totalRecords); + Scw;gO
List users = userDAO.getUserByPage(page); ~ ^)4*@i6
returnnew Result(page, users); [xg&`x9,.
} xX{gm'3UYa
6?KJ"Ai9
} c=~FXV!
*W=R:Bl!
(T2\
%8T"h
4$jb-Aw
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 %jmL#IN)
(Zv/(SE5%
询,接下来编写UserDAO的代码: zX ?@[OT
3. UserDAO 和 UserDAOImpl: MbjMO"}
java代码: E=8$*YUW(g
wx)Yl1C
I]Jz[{~1
/*Created on 2005-7-15*/ >TZyax<:
package com.adt.dao; jsnk*>j
RS[>7-9
import java.util.List; P+[\9Gg
^%k[YJtB=i
import org.flyware.util.page.Page; @If ^5s;z
e-e*%
import net.sf.hibernate.HibernateException; xdd;!HK,
2/V9Or52
/** khtYn.eaL
* @author Joa qx<h rC0Z&
*/ O%?d0K
publicinterface UserDAO extends BaseDAO { @XFy^?
k874t D
publicList getUserByName(String name)throws b(|1DE0Cv
[agp06 $D?
HibernateException; JVeb$_0k
$M 1/74
publicint getUserCount()throws HibernateException; COk;z.Kn
%>Y86>mVz
publicList getUserByPage(Page page)throws ([a[fi
~]&,v|g&
HibernateException; tW|K\NL
Auz.wes
} 2dUVHu= +
?go+oS^
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{(MC]]'?
&?mJL0fy
java代码: _@Le MNv
`$odxo+
l.Qv9Ll|b
/*Created on 2005-7-15*/ Ysz&/ry
package com.adt.dao.impl; HKZD*E((
s9'lw'
import java.util.List; <i(<|/$
2po>%Cp
import org.flyware.util.page.Page; kt*""&R
xVn"xk
import net.sf.hibernate.HibernateException; aOH$}QnS
import net.sf.hibernate.Query; 9OnH3
s]z-d!G
import com.adt.dao.UserDAO; g:sn/Zug]
. w_oW mD
/** zrg#BXj7
* @author Joa 05cyWg9a
*/ M{ mdh\
public class UserDAOImpl extends BaseDAOHibernateImpl #gL$~.1
Y]SX2kk(2
implements UserDAO { _z$lg]q
=
UT^5cl(
/* (non-Javadoc) "5,tEP!
* @see com.adt.dao.UserDAO#getUserByName :7w^2/ZGo
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(java.lang.String) {T0f]]}Q
*/ 3.
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publicList getUserByName(String name)throws ymxYE#q
g{}{gBplnl
HibernateException { YGj3W.eH
String querySentence = "FROM user in class ;QA`2$Ow
!u0qF!/W
com.adt.po.User WHERE user.name=:name"; 'F- wC!
Query query = getSession().createQuery u&!QP4$"z
Sf2pU!5n^
(querySentence); 5ZRO{rf
query.setParameter("name", name); v~2$9x!9
return query.list(); IU8/B+hM~
} o6PDCaT7
%ifq4'?Z
/* (non-Javadoc) $cxulcay=
* @see com.adt.dao.UserDAO#getUserCount() /NH9$u.g
*/ -xc*R%k
publicint getUserCount()throws HibernateException { 4|9c+^%^
int count = 0; S-^RZ"
String querySentence = "SELECT count(*) FROM q^e4
!8Rsz:7^-
user in class com.adt.po.User"; )Bl0
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Query query = getSession().createQuery G8y:f%I!b
}w0>mA0=H
(querySentence); <F=U(WWn9
count = ((Integer)query.iterate().next _\9|acFT2O
d Q5_=(9
()).intValue(); fI5]ed eS
return count; #sn2Vmi
} =,/08Cs
N6"b
OxJ(
/* (non-Javadoc) GvL)SVv?
* @see com.adt.dao.UserDAO#getUserByPage FZW)C'j
\a|FhhI
(org.flyware.util.page.Page) (QPfrR=J4
*/ ;^q@w
publicList getUserByPage(Page page)throws u*I=.
L8&$o2+07r
HibernateException { x:h0/f
String querySentence = "FROM user in class 8E m X
A/XY'3
com.adt.po.User"; d+1q[,-
Query query = getSession().createQuery wF +9Iu
IA\CBwiLj
(querySentence); K8sgeX|
query.setFirstResult(page.getBeginIndex()) QBg~b{h
.setMaxResults(page.getEveryPage()); YceX)
return query.list(); y~.k-b<{[
} /B$9B
Ue>;h9^
} 3;wAm/Z:Q
E4a`cGb
wj-=#gyAoo
)T-C/ 3
8i H'cX
至此,一个完整的分页程序完成。前台的只需要调用 EJM6TI"
z|w@eQ",
userManager.listUser(page)即可得到一个Page对象和结果集对象 or?@Ti;
#kO.'oIl
的综合体,而传入的参数page对象则可以由前台传入,如果用 Q>jx`68'KI
qSB]Zm<
webwork,甚至可以直接在配置文件中指定。 =J2\"6BnzA
o"^+ i#H!
下面给出一个webwork调用示例: :[;]6;
java代码: %?GLMf7)
%\5wHT+)
3 34UMH__
/*Created on 2005-6-17*/ c-|~ABtEpX
package com.adt.action.user; E\3fL"lM
AqPE.mf
import java.util.List; f}jo18z%
<M(Jqb cWa
import org.apache.commons.logging.Log; K4]42#
import org.apache.commons.logging.LogFactory; hxIG0d!o
import org.flyware.util.page.Page; .T*K4m{b0
tY?_#rc
import com.adt.bo.Result; r:[N#*kK
import com.adt.service.UserService; 28 h3Ayw4
import com.opensymphony.xwork.Action; ~]+-<O^U~
K+3dwQo
/** I)
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* @author Joa Ee& A5~
*/ cY%[UK $l
publicclass ListUser implementsAction{ Kd2?9gaw
Oeua<,]Z~
privatestaticfinal Log logger = LogFactory.getLog ttEQgkd`
+-b:XeHSZ
(ListUser.class); G8c 8`~t
"qL4D4
private UserService userService; p&B
c<+3e
Q.5C$I
private Page page; z93HTy9
Va^AEuzF
privateList users; 2C9wOO
Gp=X1 F
/* czMu<@c [
* (non-Javadoc) ztSP4lW
* R5`"~qP-
* @see com.opensymphony.xwork.Action#execute() ]ne&`uO
*/ f tVA
publicString execute()throwsException{ %GRD3S
Result result = userService.listUser(page); ;]ojfR=?%
page = result.getPage(); ]Y#$!fIx
users = result.getContent(); LnQm2uF
return SUCCESS; ~ vD7BO`
} 19 h7 M
IR*g>q
/** C4Pi6.wf
* @return Returns the page. X~/hv_@
*/ Pn )^mt
public Page getPage(){ DNsDEU
return page; >KjyxJ7
} x+j5vzhG)
-4P2 2
/** q6Q;9 ,
* @return Returns the users. D]+0X8@kH7
*/ lO482l_t
publicList getUsers(){ Am~ NBQ7
return users; TNs0^h)
} AXBv']Y
VKtrSY}6T
/** b6Jv|1w'
* @param page NTRw:'
* The page to set. !!Tk'=t9"3
*/ b .9]b
publicvoid setPage(Page page){ 7g(,$5
this.page = page; Xg*IOhF6x
} S>~QuCMY
;IhkGPpWP
/** 3z Jbb3e
* @param users 6&(gp(F
* The users to set. =>ooB/
*/ ien >Ou
publicvoid setUsers(List users){ 5.J$0wK'6
this.users = users; du2q6"
} u@SE)qg
8+Lig
/** &(!Sy?tNe
* @param userService sa\v9
* The userService to set. {r2-^QHF
*/ &&e{ 9{R
publicvoid setUserService(UserService userService){ xZ2}1D
this.userService = userService; ~__]E53F
} k[oU}~*U+
} Y$3H$F.+
\LB =_W$
zn5
v'`9^3(-
)i&9)_ro
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, M70X dn
E?|"?R,,,
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 8ID
fYJ
J&~nD(&TY
么只需要: )L#C1DP#
java代码: ocwRU0+j
-d\O{{%>.z
YIA}F1:
<?xml version="1.0"?> {N+N4*
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork }zVPdBRfm
S5ka;g
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 8;7Y}c
gH-e0134%
1.0.dtd"> nf!RB-orF
\ief [
<xwork> 4%O*2JAw
&)L2a)
<package name="user" extends="webwork- GDC`\cy
P8.tl"q
interceptors"> l)E
\mo
8
.:,RoK1
<!-- The default interceptor stack name S1^u/$*6
DsY-JBDvoz
--> ^GdU$%aa
<default-interceptor-ref ~*D)L'`2M
?}sh@;]*h
name="myDefaultWebStack"/> ?iG}Qj@5
]B0>r^
<action name="listUser" |E-0P=h
Kg&{
?&
class="com.adt.action.user.ListUser"> ay#cW.,
<param p8y_uNQE
`pY\Mmgv1
name="page.everyPage">10</param> ^a|$z$spf
<result l(9$s4R
u4B, |_MK
name="success">/user/user_list.jsp</result> 9BB<.
p
</action> |jm|/{lc
{s|rk
</package> N]: "3?%
OxX{[|!`
</xwork> i7 `dY{p7
zLXmjrC
w.J[3m/
=nOV!!
,.tT9?
m
*Id$%O
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 ayyn6a8
zvL&V
.>
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。 $*K5
I})la!9
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 =<(:5ive
v vlfL*f
>ZkcL7t9
T^NY|Y/
-@i)2J_WP
我写的一个用于分页的类,用了泛型了,hoho &/R@cS6}'
W5(t+$L.
java代码: wNDLN`,^H
:w(J=0Lt
nul? 5{z@
package com.intokr.util; *wP8)yv7
SqFya
import java.util.List; TW).j6@f
I*@\pc}
/** i9k7rEW^
* 用于分页的类<br> 7Upm
* 可以用于传递查询的结果也可以用于传送查询的参数<br> PB4E_0}h
* shxr^
* @version 0.01 _`/0/69
* @author cheng Km]N scq1
*/ L@S"c
(
public class Paginator<E> { I!jSAc{
privateint count = 0; // 总记录数 x@2rfs
privateint p = 1; // 页编号 PqPLy
privateint num = 20; // 每页的记录数 n=r}jRH1
privateList<E> results = null; // 结果 PTA;a0A
[ar:zlV8
/** J:f>/
* 结果总数 riZFcVsB
*/ -QIcBzw;q
publicint getCount(){ ?Li^XONz
return count; s6Bt)8A
} Y:^ =jV7
7EY~5U/4
publicvoid setCount(int count){ aen(Mcd3bg
this.count = count; XZcsx
} tA#X@HIE
,9|%
/** KwPJ0
]('_
* 本结果所在的页码,从1开始 Qat%<;P2
* D\(,:_ge
* @return Returns the pageNo. cLr? B;FS
*/ Ms1G&NYP
publicint getP(){ <tf4j3lwH
return p; wuzz Wq
} E=~H,~
kjaz{&P
/** m80+b8b
* if(p<=0) p=1 {N)\It
* P(X#w
* @param p /T#<g:
*/ l]WV?^*
publicvoid setP(int p){ UgJlXB|a%2
if(p <= 0) n,PHfydqX
p = 1; Da-F(^E
this.p = p; t)cG_+rJ
} sB0+21'R
bcM#KA
/** N#7 ]xL
* 每页记录数量 b8b-M]P-=
*/ x ?^c:`.
publicint getNum(){ rA`zuYo
return num; M|n)LyL
} )V@qH]
yqejd_cd
/** te6[^_k
* if(num<1) num=1 q/;mxq$
*/ iS=T/<|?
publicvoid setNum(int num){ "b1_vA]03
if(num < 1) g,,cV+
num = 1; Q~xR'G[N
this.num = num; z7<^aS
} T^sxR4F
FblGFm"P
/** ]G1j\ wnF
* 获得总页数 e\yj>tQJg
*/ #m$H'O[WG\
publicint getPageNum(){ G!rcY5!J
return(count - 1) / num + 1; G x,D'H'
} nn=JM7e\9
Gi<f/xQk>
/** [w{ZP4d>
* 获得本页的开始编号,为 (p-1)*num+1 Y\op9Fw
*/ 4k#B5^iJ
publicint getStart(){ I[4E?
return(p - 1) * num + 1; PN.6BJvu
} wz,
\zh
IcQ?^9%{
/** >#q|Pjv]
* @return Returns the results. 7Ru0>4B
*/ s]I],>}RU
publicList<E> getResults(){ {^\-%3$
return results; TuF:m"4
} JHQ8o5bEQp
?DRC!
9o^
public void setResults(List<E> results){ Fx@
{]
this.results = results; CD[7h
} |SxEJ
Ja (/ym^
public String toString(){ nuC K7X
StringBuilder buff = new StringBuilder djSN{>S
@"~\[z5
(); 5sE^MS1
buff.append("{"); HAiUFO/R
buff.append("count:").append(count); p/:5bvA
buff.append(",p:").append(p); gRFC n6Q
buff.append(",nump:").append(num); n -=\n6"P
buff.append(",results:").append D~y]d
{10ms_s
(results); <G&v
buff.append("}"); H,I}R
return buff.toString(); T9$U./69-L
} 7&QVw(:)M
$YC~02{
} nY8UJy}<oL
g|zK%tR_P
F#PJ+W*h