Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 \>>^eZ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 W97%12J3
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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 ]q2g[D o5
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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 oiS>:de%tc
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分页支持类: #{t?[JUn
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java代码: P9RIX;A=
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package com.javaeye.common.util; g7|$JevR0
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,
import java.util.List; V@(7K0
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publicclass PaginationSupport { ly{Q>MBM
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publicfinalstaticint PAGESIZE = 30; @"`{gdB$
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privateint pageSize = PAGESIZE; dX58nJ4u
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privateList items; R`RLq1WA
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privateint totalCount; YJ&K0%R
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privateint[] indexes = newint[0]; f.o,VVYi
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privateint startIndex = 0; 1xJc[q
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public PaginationSupport(List items, int 5nGDt~a
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totalCount){ Au6*hv3:
setPageSize(PAGESIZE); n>w/T"
setTotalCount(totalCount); WG{mg/\2(C
setItems(items); ]J
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setStartIndex(0); 4<['%7U_[
} ;Ly(O'9
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public PaginationSupport(List items, int \xH#X=J
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totalCount, int startIndex){ r/![ohrEB
setPageSize(PAGESIZE); -,;Iob56!
setTotalCount(totalCount); cdDMV%V
setItems(items); #>|l"1
setStartIndex(startIndex); WJ{hta
} U[$KQEJYj
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public PaginationSupport(List items, int ">n38:?R
[U]ouh)
totalCount, int pageSize, int startIndex){ vFK&63
setPageSize(pageSize); 7H-,:8
setTotalCount(totalCount); P~)ndaQ
setItems(items); <&?gpRK
setStartIndex(startIndex); Y}bJN%M
} RsYn6ozb
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publicList getItems(){ QL>G-Rp
return items; _)7dy2%{q
} i4Y_5
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publicvoid setItems(List items){ 0,T'z,
this.items = items; iI[Z|"a 21
} >@yHa'*9S
3&D;V;ON}_
publicint getPageSize(){ m[7i<'+S
return pageSize; IeqJ>t:
} qNhQ2x\
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publicvoid setPageSize(int pageSize){ )
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this.pageSize = pageSize; |k wkikGQS
} qzVmsxBNP
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publicint getTotalCount(){ uA?_\z?
return totalCount; #rZk&q
} \(a9rZ9
fq){?hk~O
publicvoid setTotalCount(int totalCount){ OXC7
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if(totalCount > 0){ JTw'ecFev
this.totalCount = totalCount; zX-6]j;
int count = totalCount / OE!:`Bo3T
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pageSize; T,72I
if(totalCount % pageSize > 0) ~-,P1u!
count++; rSIb1zJ
indexes = newint[count]; 8@)/a
for(int i = 0; i < count; i++){ Hp_3BulS<
indexes = pageSize * ,`/J1(\nd
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i; 27-<q5q
} um@RaU
}else{ zaX!f~;"
this.totalCount = 0; *f~X wy"
} /;M0tP
} ^;3z9}9
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publicint[] getIndexes(){ //G5lW/*
return indexes; jfyV9)
} -{>Nrx|
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publicvoid setIndexes(int[] indexes){ p6(n\eg R
this.indexes = indexes; (Al.hEs'
} L&qzX)
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publicint getStartIndex(){ ;T}#-`O_Im
return startIndex; }Po&6^
} 0px@3/
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publicvoid setStartIndex(int startIndex){ eR(PY{
if(totalCount <= 0) J!,5HJh1
this.startIndex = 0; ]6{G;f$
elseif(startIndex >= totalCount) jNN$/ZWm
this.startIndex = indexes I"E5XVC);
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[indexes.length - 1]; WigC'
elseif(startIndex < 0) ,TD@s$2x
this.startIndex = 0; #F5O>9hA
else{ ^5biD9>M
this.startIndex = indexes }%EQ
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[startIndex / pageSize];
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} \xk`o5/{
} dL<okw
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publicint getNextIndex(){ ZD1UMB0$4
int nextIndex = getStartIndex() + g2 uc+p
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pageSize; I<*U^e
if(nextIndex >= totalCount) dL>0"UN}-
return getStartIndex(); b0]y$*{j
else H~+D2A
return nextIndex; "4LYqDe
} xtKWh`[&
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publicint getPreviousIndex(){ TuphCu+Oh
int previousIndex = getStartIndex() - 3e"_R
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pageSize; U]dz_%CRP
if(previousIndex < 0) 6OMywGI[Z
return0; $=n|MbFl
else w}<BO>
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return previousIndex; \LRno3
} A>^\jIB>
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} 3|%Q{U
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抽象业务类 FsZF>vaV
java代码: 5aw#!K=J'
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/** Zb`}/%\7
* Created on 2005-7-12 w:Fes
*/ qt+vmi+~
package com.javaeye.common.business; YMnG-'^Z
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import java.io.Serializable; 7ZS5u+o
import java.util.List; M)6_Tal
dc_^
import org.hibernate.Criteria; ?s(%3_h
import org.hibernate.HibernateException; UNq!|
import org.hibernate.Session; 4xU[oaa
import org.hibernate.criterion.DetachedCriteria; ~f2H@#
import org.hibernate.criterion.Projections; !1!;}uzt
import G@h6>O
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org.springframework.orm.hibernate3.HibernateCallback; t/HMJ
import =0`"T!1
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org.springframework.orm.hibernate3.support.HibernateDaoS _h7!
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upport; ?)-*&1cv
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import com.javaeye.common.util.PaginationSupport; (7`&5md
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public abstract class AbstractManager extends 7Q} P}9n
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HibernateDaoSupport { ?Jm/v%0O
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privateboolean cacheQueries = false; ~\}%6W[2
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privateString queryCacheRegion; {<ymL}
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publicvoid setCacheQueries(boolean N%/Qc hu
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cacheQueries){ g=Q#2/UQ<
this.cacheQueries = cacheQueries; x$I~y D
} /K<Xr[z~y
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publicvoid setQueryCacheRegion(String }8GCOY
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queryCacheRegion){ ry3;60E\)
this.queryCacheRegion = E}mnGe
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queryCacheRegion; wqyx{W`~w
} `4}zB#3
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publicvoid save(finalObject entity){ qS>P,>C
getHibernateTemplate().save(entity); >Be PE(k
} <^|8\<J
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publicvoid persist(finalObject entity){ fyT:I6*
getHibernateTemplate().save(entity); *-T3'beg
} ()v[@"J
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publicvoid update(finalObject entity){ KWCA9.w4q
getHibernateTemplate().update(entity); i0Qg[%{9#
} I<z
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publicvoid delete(finalObject entity){ -#j-Zo+<
getHibernateTemplate().delete(entity); =G;whd}]
} 7EOn4I2@[
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publicObject load(finalClass entity, C0zE<fl
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finalSerializable id){ :D}xT]
return getHibernateTemplate().load 1[D~Eep
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(entity, id); z<ptrH
} 0wB ?U~
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publicObject get(finalClass entity, ;"
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finalSerializable id){ =B4mi.;@i
return getHibernateTemplate().get Xl;u
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(entity, id); N-]h+Cnyu
} x&+/da-E/5
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publicList findAll(finalClass entity){ b)(#/}jMkD
return getHibernateTemplate().find("from @G^]kDFM{
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" + entity.getName()); {6~v oVkj
} > YKvwbCf8
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publicList findByNamedQuery(finalString 4Wk/^*?
)MHvuk:I)
namedQuery){ }I}Rq D:`
return getHibernateTemplate x,@cU}D
? Sj,HLo@U
().findByNamedQuery(namedQuery); D&0*+6j((
} U
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publicList findByNamedQuery(finalString query, M '$n".,p
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finalObject parameter){ R"];`F(#
return getHibernateTemplate A&~G
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().findByNamedQuery(query, parameter); h35x'`g7+r
} 2Y\,[ $z
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publicList findByNamedQuery(finalString query, M,8a$Mdqh
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finalObject[] parameters){ ` fu(
return getHibernateTemplate BOrfKtG\
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().findByNamedQuery(query, parameters); R#`hT
} q%bNT
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publicList find(finalString query){ 73A1+2
return getHibernateTemplate().find l6:k|hrm;
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(query); _' Xt
} R4 ;^R
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publicList find(finalString query, finalObject xv]P-q0
':R)i.TS
parameter){ iSUn}%YFz!
return getHibernateTemplate().find /PE3>"|w E
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(query, parameter); #yFDC@gH1
} id\0yRBt
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public PaginationSupport findPageByCriteria e57}.pF^
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(final DetachedCriteria detachedCriteria){ 3:&!Q*i;
return findPageByCriteria yP :>vFd7
~!E%GCyFy
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 6c^2Nl8e
} 4pJOJ!?
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public PaginationSupport findPageByCriteria sHm|&
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(final DetachedCriteria detachedCriteria, finalint D06'"
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startIndex){ ((7~o?Vbg
return findPageByCriteria 'C]zB'H=
_&DI_'5q+
(detachedCriteria, PaginationSupport.PAGESIZE, ^SpD) O{
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startIndex); br.jj
} { .B^
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public PaginationSupport findPageByCriteria /d%&s^M:
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(final DetachedCriteria detachedCriteria, finalint f]^(|*6
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pageSize, ]7^OTrZ N
finalint startIndex){ sI,T"D?
return(PaginationSupport) YC - -&66
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getHibernateTemplate().execute(new HibernateCallback(){ 1`Cr1pH
publicObject doInHibernate Q!7Er
"G)-:!H
(Session session)throws HibernateException { E}-Y@( [
Criteria criteria = Wo&MHMP
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detachedCriteria.getExecutableCriteria(session); 12gcma}
int totalCount = PPU,o8E+
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((Integer) criteria.setProjection(Projections.rowCount y&-wb'==p
WEFYV=I\
()).uniqueResult()).intValue(); k|F<?:C
criteria.setProjection t/yGMR=
_}:9ic]e
(null); (=}U2GD*
List items = (NyS2`
,
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criteria.setFirstResult(startIndex).setMaxResults ZMids"Xdf
DPw"UY:
(pageSize).list(); w6+X{
PaginationSupport ps = 1"RO)&
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new PaginationSupport(items, totalCount, pageSize, EjV,&7o)
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startIndex); {'l^{"GO"
return ps; v
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} d&&^_0O
}, true); }_u1'
} &, hhH_W
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public List findAllByCriteria(final }BlVLf%C
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DetachedCriteria detachedCriteria){ KFCrJ)
return(List) getHibernateTemplate oJK1~;:
v3x_8n$C9
().execute(new HibernateCallback(){ dqwAQ-x
publicObject doInHibernate |G&<@8O
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(Session session)throws HibernateException { ;f#%0W{":
Criteria criteria = lO3$V JI
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detachedCriteria.getExecutableCriteria(session); xbnx*4o0
return criteria.list(); h-+9Bv]
} 6QkdH7Qf=
}, true); I7ZY9W(S
} A6v02WG_1T
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public int getCountByCriteria(final {Lwgj7|~
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DetachedCriteria detachedCriteria){ jq
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Integer count = (Integer) *kY\,r&!P
}dX[u`zQ
getHibernateTemplate().execute(new HibernateCallback(){ ~McmlJzJG
publicObject doInHibernate 7dyGC:YuTL
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(Session session)throws HibernateException { bq/m?;
Criteria criteria = {P"$;_Y"<
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detachedCriteria.getExecutableCriteria(session); + ObP[F
return >&6pBtC_
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criteria.setProjection(Projections.rowCount =kH7
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()).uniqueResult(); _W'>?e0i
} CMB:%
}, true); `% k9@k.
return count.intValue(); 6*8"?S'
} J@PwN^`
} ~CIA6&
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用户在web层构造查询条件detachedCriteria,和可选的 pp@Jndlg
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {R%v4#nk
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PaginationSupport的实例ps。 ~Mbo`:>(4v
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ps.getItems()得到已分页好的结果集 ((&_m9a
ps.getIndexes()得到分页索引的数组 9g3e( z@
ps.getTotalCount()得到总结果数 ,r~pf(nz
ps.getStartIndex()当前分页索引 )w(-Xc?P
ps.getNextIndex()下一页索引 ^
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ps.getPreviousIndex()上一页索引 s kC*
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 1Q"w)Ta
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 1Z%^U ?
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一下代码重构了。 ,<R/jHZP9
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我把原本我的做法也提供出来供大家讨论吧: .RFijr
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首先,为了实现分页查询,我封装了一个Page类: _^K)>
java代码: IaMZPl
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/*Created on 2005-4-14*/ {R<0'JU
package org.flyware.util.page; (3a]#`Q
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6
/** g$bbm}6S
* @author Joa ?#~3%$>
* Ey<vvZ
*/ ~Sy/q]4ys*
publicclass Page { P`r@<cgb=
#tX\m;
/** imply if the page has previous page */ iR}3 [
privateboolean hasPrePage; _`3'D`s
}dcXuX4{r
/** imply if the page has next page */ Age
privateboolean hasNextPage; XTboFrf
E_sKD ybj
/** the number of every page */ 7|Z=#3INw
privateint everyPage; _+Tq&,_:o
u&{}hv&FY
/** the total page number */ \AFoxi2h
privateint totalPage; kS_oj
Su.imM!
/** the number of current page */ N3/G6wn
privateint currentPage; Mbbgsy3W
`! ~~Wf'
/** the begin index of the records by the current v:/+OzY
JxI\ss?O
query */ 3j<:g%5
privateint beginIndex; {l/j?1Dxq
ab"6]%_
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/** The default constructor */ aY`qb Jy
public Page(){ MI8f(ZJK5
ZqT8G
} R\DdU-k
J)(KG dk
/** construct the page by everyPage 3"v
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* @param everyPage ;Q*=AW
* */ /$a>f>EJ
public Page(int everyPage){ mL\_C9k,n
this.everyPage = everyPage; i,#j@R@.C7
} Fu0"Asxce
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/** The whole constructor */ Dxp8^VL
public Page(boolean hasPrePage, boolean hasNextPage, f};lH[B3y
>
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P`z#tDT^"
int everyPage, int totalPage, v9?hcJ=
int currentPage, int beginIndex){ R"@J*\;$T
this.hasPrePage = hasPrePage; H}v.0R
this.hasNextPage = hasNextPage; '+?L/|'
this.everyPage = everyPage; $ glt%a
this.totalPage = totalPage; 2AYV9egZ
this.currentPage = currentPage; p@B/S(Xi
this.beginIndex = beginIndex; nE"##2X
} ^d6}rtG
%{M_\Ae#
/** IQz"FH?
* @return {jyI7r#X
* Returns the beginIndex. {WokH;a/
*/ `Wc"Ix0
publicint getBeginIndex(){ =[A5qwyv
return beginIndex; ai,\'%N
} &8=wkG%
k OYF]^uJ
/** 8&[Lr o9
* @param beginIndex I^}q;L![\
* The beginIndex to set. U&F1}P$fb
*/ 9)c{L<o}T
publicvoid setBeginIndex(int beginIndex){ j:|um&`)
this.beginIndex = beginIndex; d,%e?8x5
} #eRrVjbo
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/** ~7CQw^"R@
* @return V$ 8go#5
* Returns the currentPage. P:lmQHls+
*/ 5hxG\f#}?
publicint getCurrentPage(){ _xKu EU}
return currentPage; =7^rKrD
} +\Hh|Uz5
g5",jTn#
/** Z<_"Tk;!',
* @param currentPage ,K/l;M5I
* The currentPage to set. XK*55W&og
*/ $] ])FM"b
publicvoid setCurrentPage(int currentPage){ =w&bS,a"y
this.currentPage = currentPage; RSv?imi=
} 4lM)ZDg
.qd/ft2
/** seQSDCsvw*
* @return 5OJ8o>BF
* Returns the everyPage. ot%^FvQ[c
*/ hB?a{#JL
publicint getEveryPage(){ 4*`AYx(
return everyPage; MWGs:tpL4
} Z--A:D>
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/** B|\JGnNQ
* @param everyPage _cRCG1CJ
* The everyPage to set. st_.~m!/
*/ , 0hk)Vvr3
publicvoid setEveryPage(int everyPage){ _DDknQP
this.everyPage = everyPage; c[IT?6J4
} `s )-
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/** o"kVA;5<G
* @return `j#zwgUs
* Returns the hasNextPage. :D|5E>o(
*/ 54lU~ "
publicboolean getHasNextPage(){ kT@m*Etr{
return hasNextPage; DPWt=IFU
} l1 M
%
AfAlDM'
/** mp'Z.4
* @param hasNextPage Yg<L pjq5X
* The hasNextPage to set. Ri
*/ #oYPe:8|m
publicvoid setHasNextPage(boolean hasNextPage){ 6D\$K
this.hasNextPage = hasNextPage; B5A/Iv)2
} ~vb yX
9 HiH6f^5
/** 3BZa}Q_
* @return 7I $~E
* Returns the hasPrePage. '!hA!eo>J
*/ yjF;%A/0
publicboolean getHasPrePage(){ "^froQ{"T
return hasPrePage; ia9=&Hy])
} z [|:HS&
Tqf:G4!
/** +GYO<N7
* @param hasPrePage ,J$XVvwxF
* The hasPrePage to set. `MLOf
*/ ]Pp}=hcD
publicvoid setHasPrePage(boolean hasPrePage){ p{vGc-zP.
this.hasPrePage = hasPrePage; _Xqa_6+/
} '5)PYjMnH
m{w'&\T
/** BNw};.lO
* @return Returns the totalPage. f0|wN\
* ?~:4O}5Ax
*/ [yhK4A
publicint getTotalPage(){ mEZHrr J
return totalPage; Ueb&<tS
} c98^~vR]]
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/** c:[8ng 2v
* @param totalPage J+(B]8aj
* The totalPage to set. Pf:;iXH?
*/ w paI}H#
publicvoid setTotalPage(int totalPage){ sU$<v( `"
this.totalPage = totalPage; #iiXJnG
} M*-]<!))7
<-h[I&."
} {y%|Io`P
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 B'v~0Kau
3
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个PageUtil,负责对Page对象进行构造: 5-RA<d#
java代码: %HD0N&
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/*Created on 2005-4-14*/ 47=YP0r?>T
package org.flyware.util.page; Qx_]oz]NY
}Pm;xHnf&
import org.apache.commons.logging.Log; Z VyJ%"(E
import org.apache.commons.logging.LogFactory; s/0bXM$^
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/** q&kG>
* @author Joa eyzXHS*s;L
* W,5_i7vr
*/ X@Bg_9\i
publicclass PageUtil { [OYSNAs*y
D=jtXQF
privatestaticfinal Log logger = LogFactory.getLog 7$JOIsM
ET[>kn^#
(PageUtil.class); 3De(:c)@
s}<i[hY>
/** |vPU]R>6
* Use the origin page to create a new page
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* @param page }F';"ybrU)
* @param totalRecords 9]^q!~u
* @return emMk*l,
*/ lyzM?lK-
publicstatic Page createPage(Page page, int %w;wQ_
j%)@f0Ng
totalRecords){ o&)v{q
return createPage(page.getEveryPage(), '[vCC'
jpkKdQX)
page.getCurrentPage(), totalRecords); jSQM3+`b
} GQ 0(lS
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/** 13p.dp`
* the basic page utils not including exception cz1 m05E
P#9Pq,I
handler =>-W!Of
* @param everyPage 8I7JsCj
* @param currentPage 2<E@f0BVAy
* @param totalRecords wWVB'MRXB,
* @return page tkP& =$
*/ [
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publicstatic Page createPage(int everyPage, int )S9}uOG#
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currentPage, int totalRecords){ zgl$ n
everyPage = getEveryPage(everyPage); s_P[lbHt.
currentPage = getCurrentPage(currentPage); *>k6n5%
int beginIndex = getBeginIndex(everyPage, KP_7h/e
JYnyo$m/
currentPage); wAo6:)
int totalPage = getTotalPage(everyPage, qGi\*sc>x
d~KTUgH'<
totalRecords); GA"vJFQ
boolean hasNextPage = hasNextPage(currentPage,
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$+ORq3
totalPage); uMjL>YLq{?
boolean hasPrePage = hasPrePage(currentPage); qu0q
LM
i(4.7{*
returnnew Page(hasPrePage, hasNextPage, gNC'kCx0c
everyPage, totalPage, z+c'-!e/
currentPage, n5Mhp:zc,
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beginIndex); |fY#2\)Yx
} #V.u[:mO
XEUS)X)
privatestaticint getEveryPage(int everyPage){ qga\icQr
return everyPage == 0 ? 10 : everyPage; L>pSE'}
} ~i0>[S3'
O&Y22mu
privatestaticint getCurrentPage(int currentPage){ b_)SMAsO7
return currentPage == 0 ? 1 : currentPage; #n+sbx5~7
} Of#"nu
tm.&k6%
privatestaticint getBeginIndex(int everyPage, int \[
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1
J[z ![Tf
currentPage){ @9lGU#
return(currentPage - 1) * everyPage; *,
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} ]YY4{E(9d
uT
Y G/O
privatestaticint getTotalPage(int everyPage, int A:\_ \B%<
e 8^%}\F
totalRecords){ .*?)L3n+t
int totalPage = 0; hVdGxT]6
}tJMnq/m($
if(totalRecords % everyPage == 0) orFB*{/Z
totalPage = totalRecords / everyPage; ?4t~z 1.f
else MfraTUxIo/
totalPage = totalRecords / everyPage + 1 ; 212 =+k
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return totalPage; 88}0 4
} b/4gs62{k
N6v*X+4JH
privatestaticboolean hasPrePage(int currentPage){ y2PxC. -
return currentPage == 1 ? false : true; &zPM#Q
} u1|v3/Q-
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`
privatestaticboolean hasNextPage(int currentPage, &{8[I3#@
^y~oXS(
int totalPage){ I]B9+Z?xo
return currentPage == totalPage || totalPage == _k5$.f:Yj<
iig&O(,
0 ? false : true;
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} Is97>aid
bBQHxH}vi
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} V /)3d
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6wb M$|yFj
nTsPX Tat
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。 P.~sNd oJ
#Z]<E6<=9
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 -./Y
xG(:O@
做法如下: 0qBXL;sE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 M<@9di7c
r?x~`C
的信息,和一个结果集List: z=LO$,JW`
java代码: /Wy9".
(; Zl
ltd'"J/r
/*Created on 2005-6-13*/ iz-O~T/^
package com.adt.bo; *}LQZFrnX
_K~?{".
import java.util.List; +*RpOtss
+@PZ3
[s
import org.flyware.util.page.Page; K=2j}IPe
}80n5X<9
/** ,->
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* @author Joa 7wqD_Xr
*/ Z8pZm`g)T
publicclass Result { u[!Ex=9W
=PoPp
private Page page; qche7kg!a
tI2p-d9B
private List content; Pv@;)s(-
*8 ]
/** b;I!CyD
* The default constructor Bc#6mO-
*/ +Jc-9Ko\c;
public Result(){ '`p0T%w
super(); #p=Wt&2
} F#{PJ#
U3w*z6OG
/** r3.v ^
* The constructor using fields wD[qE
* hpticW|
* @param page >2)!w
* @param content zyI4E\
*/ & l~=c2
public Result(Page page, List content){ =`%%*
this.page = page; {XYf"ONi
this.content = content; $Vm J[EF1
} 3K_!:[
%P]-wBJw
/** QLTE`t5w3'
* @return Returns the content. g? \pH:|79
*/ {c$%3iQq
publicList getContent(){ fGLOXbsA
return content; .{]=v
} [g*]u3s
u"a$/
/** ;D<rGkry
* @return Returns the page. NPR{g!tK%
*/ !!t@H\
public Page getPage(){
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return page; ]%%cc
} k<S!|
Z8Clm:S
/** AwL;-|X
* @param content 3!B3C(g
* The content to set. HjN )~<j
*/ 6_a.`ehtj<
public void setContent(List content){ 2!Ex55
this.content = content; zphStiwIQ
} ~9ILN~91
v6?<)M%
/** ,K[B/tD{j
* @param page }~5xlg$B<<
* The page to set. Jh:-<xy)
*/ 3'2}F%!Mv
publicvoid setPage(Page page){
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this.page = page; l@YpgyqaL
} #$%gs]
} 9/|i.2&
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k07) g:_
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IA;KEGJ
2. 编写业务逻辑接口,并实现它(UserManager, mwTn}h3N
>Y< y]vM:
UserManagerImpl) 2jx+q
java代码: z95V 7E
Bf88f<Z
y]\R0lR
/*Created on 2005-7-15*/ i&FC-{|Z
package com.adt.service; QX~*aqS3s8
Ic&t_B*i}]
import net.sf.hibernate.HibernateException; _>:g&pS/
tdr*>WL
import org.flyware.util.page.Page; 4/U]7Y
_.06^5o
import com.adt.bo.Result; @kwD$%*0
AjANuyUaP
/** @]#+`pZ4A
* @author Joa ~K],hi^<P
*/ z(orA} [
publicinterface UserManager { l7J_s?!j
pN]Hp"v
public Result listUser(Page page)throws )x|BY>
|:r/K
HibernateException; |I+E`,n"b
y!!+IeReS
} e?lqs,m@"
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8h20*@wSN
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java代码: @7^#_772
16Gv?
I
h
qryt1~Dq
/*Created on 2005-7-15*/ 3Ob"r`
package com.adt.service.impl; -;`W"&`ss
^Q :K$!
import java.util.List; nLfnikw&
*E)Y?9u"
import net.sf.hibernate.HibernateException; F<(xz=
.DvAX(2v
import org.flyware.util.page.Page; LMG\jc?,
import org.flyware.util.page.PageUtil; M<~F>(wxA
NxX1_d
import com.adt.bo.Result; N[+dX_h
import com.adt.dao.UserDAO; D[#\Y+N
import com.adt.exception.ObjectNotFoundException; MM8)yCI
import com.adt.service.UserManager; };!c]/,
NJtB ;
/** eu:_V+
* @author Joa ;W*$<~_
*/ E0DEFB
publicclass UserManagerImpl implements UserManager { eXaDx%mM
Rt:PW}rFf
private UserDAO userDAO; GKd>AP_
6~/H#8Kdn
/** P*T)/A%4
* @param userDAO The userDAO to set. )eV40l$
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*/ w9PY^U.Y3e
publicvoid setUserDAO(UserDAO userDAO){ ::`j@ ]
this.userDAO = userDAO; GQZUC\cB
} J;kbY9e
jw[`_
/* (non-Javadoc) O46/[{p+8
* @see com.adt.service.UserManager#listUser Elq8WtS
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(org.flyware.util.page.Page) M1M]]fT0ME
*/ -)I _+N
public Result listUser(Page page)throws ,/ : )FV
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HibernateException, ObjectNotFoundException { zLn#p]
int totalRecords = userDAO.getUserCount(); nz',Zm},
if(totalRecords == 0) sq^"bLw
throw new ObjectNotFoundException QE}@|H9xs
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("userNotExist"); r/T DU[`&
page = PageUtil.createPage(page, totalRecords); WE7l[<b
List users = userDAO.getUserByPage(page); 7@"X~C
returnnew Result(page, users); XHg%X
} Q}T9NzOH%
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} e4b~s
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 !jW32$YTR
"%]dC{
询,接下来编写UserDAO的代码: wg1pt1 `
3. UserDAO 和 UserDAOImpl: HlSuhbi'@
java代码: wm8x1+P
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8dhY"&
/*Created on 2005-7-15*/ .-ABo]hf
package com.adt.dao; Dn3~8
l!=WqIZ
import java.util.List; ;R!H\
`IoX'|C[h
import org.flyware.util.page.Page; Chup %F
|@ HdTGD
import net.sf.hibernate.HibernateException; 7e<Q{aB
1X*T219o
/** K?je(t^
* @author Joa ]`XuE-Uh
*/
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publicinterface UserDAO extends BaseDAO { 9-^p23.@[j
f tPw6
publicList getUserByName(String name)throws QA(,K}z~^S
h'x~"k1
HibernateException; v1=X =H
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publicint getUserCount()throws HibernateException; /<$"c"UQ
d"UW38K{
publicList getUserByPage(Page page)throws ,no:6
WLLv a<{
HibernateException; $hQg+nY.
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} sJ/e=1*
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java代码: ^BX@0"&-
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YoJ'=z,e
/*Created on 2005-7-15*/ !f-o,RJ
package com.adt.dao.impl; J#DcT@
HJR<d&l;p
import java.util.List; zYdtQjv
i@Zj7#e*
import org.flyware.util.page.Page; e}[we:
B?yt%f1
import net.sf.hibernate.HibernateException; :(`>bY
import net.sf.hibernate.Query; CJixK>Y^
~bTae =FP
import com.adt.dao.UserDAO; ;x^,t@ xge
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/** b
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* @author Joa c$kb0VR
*/ ON0+:`3\
public class UserDAOImpl extends BaseDAOHibernateImpl Q;/F0JDH
Ch9!AUiR
implements UserDAO { +~Ay h[V
O)uM&B=
/* (non-Javadoc) |S:!+[
* @see com.adt.dao.UserDAO#getUserByName xPup?oP >
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(java.lang.String) '5/}MMT
*/ dJ:x1j
publicList getUserByName(String name)throws Q'%o;z*
_-J @$d%
HibernateException { sC_UalOC_
String querySentence = "FROM user in class /2Lo{v=0[
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com.adt.po.User WHERE user.name=:name"; ~<-
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Query query = getSession().createQuery V?59.TJ
uyt-q|83=
(querySentence); :wZ`>,K"t>
query.setParameter("name", name); B"9hQb
return query.list(); iv+jv2ZF%
} d5"EvT
8]":[s6x
/* (non-Javadoc) <>i+R#u{
* @see com.adt.dao.UserDAO#getUserCount() n qLAby_
*/ -5v.1y=!L
publicint getUserCount()throws HibernateException { gQ=POJ=G
int count = 0; kj!7|1i2
String querySentence = "SELECT count(*) FROM Au} ;z6k
^;$a_$|
user in class com.adt.po.User"; ]Y&)98
Query query = getSession().createQuery |;9 A{#zM
!u{"] T:
(querySentence); Z/kaRnG[@t
count = ((Integer)query.iterate().next p_qm}zp
:LiDJF
()).intValue(); Z3So|M{v
return count; xY'qm8V
} CEuk1$
M:Y*Tb6w
/* (non-Javadoc) )YMlFzYr
* @see com.adt.dao.UserDAO#getUserByPage
NJ)2+
j'Y"/<
(org.flyware.util.page.Page) Dbdzb m7
*/ )6:]o&bZ
publicList getUserByPage(Page page)throws Lv5X 'yM
aZjef
HibernateException { 2\63&C^
String querySentence = "FROM user in class f\);HJbg
M"5!s,
com.adt.po.User"; kq%gY
Query query = getSession().createQuery P%@rH@^Y
Z1$];Q\cX
(querySentence); )@bH"
query.setFirstResult(page.getBeginIndex()) +#qt^NO
.setMaxResults(page.getEveryPage()); 9;]wF8h
return query.list(); 5Z6-R}uXk
} MkW1FjdP
,+/9K)X
} [Ba2b: l6v
W`u$7k]$
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|5~wwL@LW7
f']sU/c=
至此,一个完整的分页程序完成。前台的只需要调用 ri<'-w i
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userManager.listUser(page)即可得到一个Page对象和结果集对象 K 5qLBz@U
<F)w=_%&
的综合体,而传入的参数page对象则可以由前台传入,如果用 5B>Q6
jemxky
webwork,甚至可以直接在配置文件中指定。 6I&j
cHH
+t>*l>[
下面给出一个webwork调用示例: UOu6LD/|h
java代码: 6c2ThtL
n4WSV
YO(:32S
/*Created on 2005-6-17*/ p584)"[*t
package com.adt.action.user; P#[IUXtT
X"k^89y$
import java.util.List; 'Gl;Ir^
<+\k&W&Y|y
import org.apache.commons.logging.Log; ~TG39*m
import org.apache.commons.logging.LogFactory; a*6wSAA )
import org.flyware.util.page.Page; R 5K-KSvW
R2N^'
import com.adt.bo.Result; 13.{Y)
import com.adt.service.UserService; bk7^%O>
import com.opensymphony.xwork.Action; &gWMl`3^*!
@TA8^ND
/** JN&MyA"
* @author Joa m)@Q_{=6M
*/ Mr=}B6`
publicclass ListUser implementsAction{ K5!";V
3s?v(1 {)
privatestaticfinal Log logger = LogFactory.getLog _b0S
m|[\F#+C
(ListUser.class); nY{i>Y
NokXE
private UserService userService; U~{Sa+
gb=80s0
private Page page; YER:ICQ
ZI58XS+
privateList users; DYo<5^0
wi\z>'R
/* Y_[g_
* (non-Javadoc) 068WlF cWV
* y _'e yR@)
* @see com.opensymphony.xwork.Action#execute() C~ZE95g
*/ 3VcT7y*{P
publicString execute()throwsException{ $R%+*
Result result = userService.listUser(page); U_x0KIm
page = result.getPage(); J 16=!q()
users = result.getContent(); 1Q&cVxA"\
return SUCCESS; tLS<0
} E\R raPkQT
Z!wD~C"D73
/** d[Rb:Yw
* @return Returns the page. |h^K M
*/ 2f3=?YqD
public Page getPage(){ >.J'L5
x$
return page; 8?e
} |`w$|pm=
ra]!4Kd'
/** #"Fg%36Zd
* @return Returns the users. 99F>n[5
*/ E x_L!9>!
publicList getUsers(){ D^,\cZbY
return users; M'\pkzx
} CxJfrI_W
pNp^q/-yB
/** J3H.%m!V
* @param page KU+( YF$1
* The page to set. d@-wi%,^
*/ YO)')&
publicvoid setPage(Page page){ %S{o5txo
this.page = page; /GsSrP_?]
} o*%3[HmV
&}zRH}s;
/** w`M]0'zls
* @param users OYBotk]{1
* The users to set. d4ic9u*D
*/ (JevHdI*V
publicvoid setUsers(List users){ @(i*-u3Tq
this.users = users; jZrY=f
} ]|,vCKju
iH[E=
6*
/** +yth_9
* @param userService De;, =BSp
* The userService to set. (tJ91SBl
*/ Qn*6D
publicvoid setUserService(UserService userService){ G-2EQ.
this.userService = userService; DZJeup?Z
} (F_w>w.h
} Tc:sldtCk
c2/FHI0J;
rW[SU:
'yE*|Sx
`/c7h16
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, -dg} BM
u-lrTa""z
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 *7\W=-
%njOX#.w
么只需要: :ezA+=ENg
java代码: DX|uHbGg
pw!@Q?R
B9wp*:.
<?xml version="1.0"?> 'w}p[(
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ;JYoW{2
?3[tJreVj
1.0//EN" "http://www.opensymphony.com/xwork/xwork- pXssh
Dft4isyt^
1.0.dtd"> %Hh3u$Y,
o5>/}wIf
<xwork> /n(9&'H<
-=}b;Kf-
<package name="user" extends="webwork- rWJ*e Y
\kxh#{$z?
interceptors"> TNx _Rc}
\F[n`C"Is
<!-- The default interceptor stack name T\jAk+$Jo
mIRAS"Q!m
--> C}9Kx }q
<default-interceptor-ref .U<F6I:<md
fO#?k<p
name="myDefaultWebStack"/> k'x#t(
rmoJ
=.'
<action name="listUser" #7+]%;h
^=k{~
class="com.adt.action.user.ListUser"> A&NqQ
V,
<param 6>s=CiZB
pOKeEW<q
name="page.everyPage">10</param> =9(tsB gTX
<result X\kjAMuW/*
NK~PcdGl
name="success">/user/user_list.jsp</result> k9l^6#<?
</action> *=TYVM9
xLZ bU4
</package> ZlrhC= 0
s*f1x N<
</xwork> qT$)Rb&
Y5n>r@)m
J=@xAVBc
|f<9miNu
V7BsE w
B7|c`7x(
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 -rO*7HO
5:$Xtq
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。 n6/f an;
l/M[am
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 5E`JD
[$;,Ua-mt
W=3? x
V;k#})_-
l**3%cTb
我写的一个用于分页的类,用了泛型了,hoho 4j^bpfb,
!x8kB
Di,
java代码: L$SMfx
x df?nt
7x(v?
package com.intokr.util; .D!WO
t?HF-zQ
import java.util.List; 6(>WGR
'aZASPn[
/** S_$nCyaH2
* 用于分页的类<br> eKyqU9
* 可以用于传递查询的结果也可以用于传送查询的参数<br> pu#[pa
* HJ",Sle
* @version 0.01 =6fB*bNk]
* @author cheng RbKwO}
z$q
*/ bf(+ldq
public class Paginator<E> { R1Yqz $#
privateint count = 0; // 总记录数
jC4O`
privateint p = 1; // 页编号 o<nS_x
privateint num = 20; // 每页的记录数 &1l~&,,
privateList<E> results = null; // 结果 <