Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 E+95WF|4k"
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 D@ek9ARAq
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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 F=a+z/xKT
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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 kma?v B
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分页支持类: a6xj\w
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java代码: RzKb{>
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package com.javaeye.common.util; #s-iy+/1oN
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import java.util.List; [tT8_}v$LN
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publicclass PaginationSupport { C@\{ehG
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publicfinalstaticint PAGESIZE = 30; JAc_kl{4O
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privateint pageSize = PAGESIZE; l:|D,q
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privateList items; QbFHfA2Ij
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privateint totalCount; jyS=!ydn+
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privateint[] indexes = newint[0]; ChrY"
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privateint startIndex = 0; d50Vtm\
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public PaginationSupport(List items, int `TqSQg_l
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totalCount){ a
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setPageSize(PAGESIZE); ,U,By~s
setTotalCount(totalCount); ;Y9=!.Ak0y
setItems(items); I5ss0JSl/
setStartIndex(0); yc;3Id5?>
} xg`h40c
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public PaginationSupport(List items, int imB# Eo4eY
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totalCount, int startIndex){ <~U4*
setPageSize(PAGESIZE); gwkb!#A
setTotalCount(totalCount); yY{kG2b,
setItems(items); @r^!{
setStartIndex(startIndex); ]w).8=I
} <z+:j!~
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public PaginationSupport(List items, int BcWcdr+}9
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totalCount, int pageSize, int startIndex){ -XK0KYhgW
setPageSize(pageSize); F4#g?R::U
setTotalCount(totalCount); b}!3;: iD
setItems(items); rM}0%J'
setStartIndex(startIndex); S:Q! "U
} `m@U!X
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publicList getItems(){ UM%o\BiO
return items; FjfN3#qlg
} 9W7#u}Z
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publicvoid setItems(List items){ t
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this.items = items; kT IYD o
} +%>:0mT
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publicint getPageSize(){ 9v)%dO.
return pageSize; bKVj [r8D~
} D>L2o88
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publicvoid setPageSize(int pageSize){ WKM)*@#,
this.pageSize = pageSize; hn)a@
} .9G<y 4
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publicint getTotalCount(){ .\3`2
return totalCount; t q50fq'
} /TQ}}
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publicvoid setTotalCount(int totalCount){ 10[Jl5+t
if(totalCount > 0){ yq[Cq=rBk
this.totalCount = totalCount; n| O [a6G
int count = totalCount / m*0,s
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pageSize; 1^J`1
if(totalCount % pageSize > 0) SS|z*h
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count++; ;oOv/3
indexes = newint[count]; }u{gR:lZ
for(int i = 0; i < count; i++){ gYAF'?
indexes = pageSize * i8X`HbmN
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} @ez Tbc3
}else{ x|64l`Vp(:
this.totalCount = 0; vEe NW
} 9.O8/0w7LV
} k,Qskd-N]
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publicint[] getIndexes(){ ks;%*d
return indexes; `\Ku]6J]5
} \$*$='6"
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publicvoid setIndexes(int[] indexes){ XEM'}+d
this.indexes = indexes; +V862R4,o
} q~K(]Ya/
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publicint getStartIndex(){ &F$:Q:* *
return startIndex; d5I f"8`@
} ]<uQ.~
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publicvoid setStartIndex(int startIndex){ X2 6
if(totalCount <= 0) %bXtKhg5eJ
this.startIndex = 0; Mn: /1eY
elseif(startIndex >= totalCount) 7cg*|E@
this.startIndex = indexes 7sNw
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[indexes.length - 1]; H&}ipaDO
elseif(startIndex < 0) 'BMy8
this.startIndex = 0; ra '
else{ ,hxkk`
this.startIndex = indexes \[2lvft!
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[startIndex / pageSize]; >?W[PQ5 yx
} &Bb<4R
} xgsjm))
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publicint getNextIndex(){ ~q +[<xR\
int nextIndex = getStartIndex() + ITuq/qts]A
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pageSize; {4 >mc'dv
if(nextIndex >= totalCount) bEuaOBc
return getStartIndex(); v0*N)eqDGd
else %!Q`e79g8
return nextIndex; N@o?b
} \g)Xt?w0Wo
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publicint getPreviousIndex(){ g\oSG)
int previousIndex = getStartIndex() - 9<CG s3\
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pageSize; u8zbYd3
if(previousIndex < 0) }}{!u0N},V
return0; 6"j_iB
else 0IM8
return previousIndex; "R
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} woH)0v
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} 72oWhX=M%
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抽象业务类 v*hRz;
java代码: gW(gJ;
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/** n7LfQWc
* Created on 2005-7-12 DR9: _
*/ Si}HX!s
package com.javaeye.common.business; G)=HB7u[a
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import java.io.Serializable; ^S)TO}e
import java.util.List; [(LV
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import org.hibernate.Criteria; )QKf7 [:
import org.hibernate.HibernateException; De
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import org.hibernate.Session; ["<nq`~
import org.hibernate.criterion.DetachedCriteria; :Gqy>)CxX
import org.hibernate.criterion.Projections; Tn-C>=tR~%
import DdV'c@rq+
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org.springframework.orm.hibernate3.HibernateCallback; o(A|)c4k
import ;bu#8,
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org.springframework.orm.hibernate3.support.HibernateDaoS [jx0-3s:X
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upport; Hq &"+1F
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import com.javaeye.common.util.PaginationSupport; Z~G my7h(
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public abstract class AbstractManager extends 6Q|k7*,B
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HibernateDaoSupport { :y]Omp
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privateboolean cacheQueries = false; H!e 3~+)
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privateString queryCacheRegion; iSK+GQ~
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publicvoid setCacheQueries(boolean :
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cacheQueries){ $ls[|N:y0l
this.cacheQueries = cacheQueries; M
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} 5,"l0nrk
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publicvoid setQueryCacheRegion(String >r5P3G1
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queryCacheRegion){ +y+"Fyl
this.queryCacheRegion = xk~IN%\
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queryCacheRegion; ]6Ug>>x5
} zkM"cb13q/
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publicvoid save(finalObject entity){ 4] > ]-b
getHibernateTemplate().save(entity);
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} = iB,["s
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publicvoid persist(finalObject entity){ ~i'Nqe_
getHibernateTemplate().save(entity); ;Z[]{SQ
} V5}nOGV9
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publicvoid update(finalObject entity){ SD\=
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getHibernateTemplate().update(entity); /{2*WI;
} }n,Zl>T9
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publicvoid delete(finalObject entity){ qMBR *f
getHibernateTemplate().delete(entity); Is<"OQ
} ]-o"}"3Ef
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publicObject load(finalClass entity, "ceed)(:
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finalSerializable id){ _&3<6$}i"
return getHibernateTemplate().load |iFVh$N
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(entity, id); u),Qa=Wp
} ` >!n
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publicObject get(finalClass entity, _#e&t"@GS
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finalSerializable id){ o;"OSp
return getHibernateTemplate().get *=" 8?Z
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(entity, id); -u!qrJ*Z
} stl 1QO(h
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publicList findAll(finalClass entity){ `pZs T
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return getHibernateTemplate().find("from {)f~#37
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" + entity.getName()); G}@#u9
} /(I*,.d
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publicList findByNamedQuery(finalString \b'xt
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namedQuery){ u.pxz8
return getHibernateTemplate SxgYjIa-
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().findByNamedQuery(namedQuery); :A46~UA!$
} :^ i9]
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publicList findByNamedQuery(finalString query, <<9Va.
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finalObject parameter){ ~wnOV#v
return getHibernateTemplate Z{IUy
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().findByNamedQuery(query, parameter); ^_I} x)i*@
} bok.j
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publicList findByNamedQuery(finalString query, sGDV]~E
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finalObject[] parameters){ !2CL1j0(
return getHibernateTemplate Mkp/0|Q*
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().findByNamedQuery(query, parameters); M
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} %HQ.|
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publicList find(finalString query){ m4k
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return getHibernateTemplate().find gV1[3dW
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(query); (%CZ*L[9Z
} Ph&urxH@
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publicList find(finalString query, finalObject T[k4lM
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parameter){ :WGtR\tK
return getHibernateTemplate().find LL^q1)o
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(query, parameter); 5OIc(YhYf
} K)7zKEp`cj
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public PaginationSupport findPageByCriteria -${DW^txMZ
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(final DetachedCriteria detachedCriteria){ 1L7{p>;-dO
return findPageByCriteria C<^YVeG
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }F6<w{|
} EO|:FcW
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public PaginationSupport findPageByCriteria d|9b~_::V
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(final DetachedCriteria detachedCriteria, finalint rjt8fN
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startIndex){ -b&{+= ^c
return findPageByCriteria [./6At&|
}/dRU${!
(detachedCriteria, PaginationSupport.PAGESIZE, ubsSa}$q
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startIndex); I:&/`K4,x,
} `Ycf]2.,$
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public PaginationSupport findPageByCriteria p1pQU={<
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(final DetachedCriteria detachedCriteria, finalint qIUfPA=/_
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pageSize, # M, 7
finalint startIndex){ )"(] Lf's
return(PaginationSupport) |LG4=j.l
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getHibernateTemplate().execute(new HibernateCallback(){ %m,6}yt
publicObject doInHibernate Kyt)2p
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(Session session)throws HibernateException {
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Criteria criteria = 5[l8y,
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detachedCriteria.getExecutableCriteria(session); 0l*]L`]L#
int totalCount = E9\vA*a
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((Integer) criteria.setProjection(Projections.rowCount k-V,~c
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()).uniqueResult()).intValue(); M$4k;
criteria.setProjection e"]8T},
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(null); VpfUm?Nq
List items = [u@Jc,
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criteria.setFirstResult(startIndex).setMaxResults <tpmUA[]
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(pageSize).list(); UsGa
PaginationSupport ps = 5wB =>
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new PaginationSupport(items, totalCount, pageSize, ~I/@i
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startIndex); CZnK8&VDY
return ps; HD,xY4q&N
} .Ig+Dj{)
}, true); +h^jC9,m~{
} 2M<R(W!&
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public List findAllByCriteria(final dG QG!l+>
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DetachedCriteria detachedCriteria){ ,jA)wJ
return(List) getHibernateTemplate 3<=,1 cU
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().execute(new HibernateCallback(){ "q}FPJ^l_N
publicObject doInHibernate bawJ$_O_
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(Session session)throws HibernateException { jdKOb
Criteria criteria = I jr\5FA[p
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detachedCriteria.getExecutableCriteria(session); 65z"
return criteria.list(); ^
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} -aRU]kIf
}, true); :.(;<b<\
} uZa9zs=}c
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public int getCountByCriteria(final #ywk|k5z]
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DetachedCriteria detachedCriteria){ W)'*m-I
Integer count = (Integer) qbrp P(.
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getHibernateTemplate().execute(new HibernateCallback(){ u$%t)2+$4
publicObject doInHibernate U<XSj#&8|
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(Session session)throws HibernateException { Qjx?ri//
Criteria criteria = s?8<50s
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detachedCriteria.getExecutableCriteria(session); $,I q;*7N
return (%iRaw7hp
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criteria.setProjection(Projections.rowCount tH=P6vY
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()).uniqueResult(); b[z]CP
} jVLA CWH
}, true); }:: S0l
return count.intValue(); MT(o"ltQ
} 5<I
} f>BWG`
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用户在web层构造查询条件detachedCriteria,和可选的 FZreP.2)!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _%'},Xd.z
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PaginationSupport的实例ps。 ?!qY,9lhH
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ps.getItems()得到已分页好的结果集 TJE\A)|>g
ps.getIndexes()得到分页索引的数组 6y%0`!
ps.getTotalCount()得到总结果数 !+u"3;%h
ps.getStartIndex()当前分页索引 .4.b*5
ps.getNextIndex()下一页索引 5cx#SD&5/
ps.getPreviousIndex()上一页索引 }@if6(0
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 /0\
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ,C3,TkA]
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一下代码重构了。 q2HYiH^L
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我把原本我的做法也提供出来供大家讨论吧: RN=` -*E1
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首先,为了实现分页查询,我封装了一个Page类: =4d (b ;
java代码: HF|oBX$_
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/*Created on 2005-4-14*/ J>d.dq>r
package org.flyware.util.page; O-)-YVU
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/** Vh>Z,()>>@
* @author Joa p~LrPWHSTP
* n~VD uKn9
*/ <nEi<iAY>U
publicclass Page { G
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/** imply if the page has previous page */ q -8t'7
privateboolean hasPrePage; zbJT&@z
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/** imply if the page has next page */ ;c$ J=h]
privateboolean hasNextPage; .k,YlFvj
CdL< *AH
/** the number of every page */ 0527Wj
privateint everyPage; ^*fQX1h<
vloF::1
/** the total page number */ ftH:r_"O#
privateint totalPage; KZPEG!-5
B=|cS;bM$3
/** the number of current page */ X$/2[o#g
privateint currentPage; dH( ('u[
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/** the begin index of the records by the current uslQ*7S[^
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query */ XrZ*1V
privateint beginIndex; V)}rEX
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/** The default constructor */ F-6c_!
public Page(){ \TU3rk&X
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-?
} Z0l+1iMx
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/** construct the page by everyPage QY= = GfHt
* @param everyPage Y3Q9=u*5
* */ $ImrOf^qt
public Page(int everyPage){ Y`?-VaY
this.everyPage = everyPage; Agrk|wPK
} \6\<~UX^
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/** The whole constructor */ B7imV@<
public Page(boolean hasPrePage, boolean hasNextPage, s&j-\bOic9
=hl }.p
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int everyPage, int totalPage, gCyW Vp
int currentPage, int beginIndex){ {T].]7Z
this.hasPrePage = hasPrePage;
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this.hasNextPage = hasNextPage; >t7x>_~
this.everyPage = everyPage; y+7PwBo%e
this.totalPage = totalPage; '(/7[tJ
this.currentPage = currentPage; yr,=.?C-
this.beginIndex = beginIndex; {s;U~!3aY
} ElUEteZ
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/** %j7XEh<'
* @return @V!r"Bkg.
* Returns the beginIndex. bV"G~3COy
*/ p)+k=b
publicint getBeginIndex(){ cph:y
return beginIndex; NFv>B>
} ^Ox3XC
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/** Wl}&?v&@
* @param beginIndex 7F'`CleU
* The beginIndex to set. j)q\9#sI/(
*/ &4_qF^9J
publicvoid setBeginIndex(int beginIndex){ i&n'N8D@
this.beginIndex = beginIndex; /t(C>$ }p
} mx=BD'
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/** h yv2SxP*
* @return 2PG [7u^
* Returns the currentPage. Sf8{h|71
*/ -
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publicint getCurrentPage(){ 7VP32Eh[
return currentPage; +]Y,q
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} Tyck/ EO
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/** 1UQHq@aM
* @param currentPage G%Lt.?m[
* The currentPage to set. b6*!ACY
*/ ]~Z6;
publicvoid setCurrentPage(int currentPage){ 0#MqD[U(
this.currentPage = currentPage; //aF5:Y#
} Gw1@KKg
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/** F;>!&[h}G
* @return 'PP#^aI,
* Returns the everyPage. ^4o;$u4R
*/ R=KQ
publicint getEveryPage(){ vI@%Fg+D
return everyPage; wiBVuj#
} Ox@P6|m
^I+)o1%F
/** *2GEnAZb7n
* @param everyPage J4\ qEO
* The everyPage to set. h5K$mA5
*/ CoA6
publicvoid setEveryPage(int everyPage){ 8}(]]ayl
this.everyPage = everyPage; oqeSG.1
} }C|dyyr
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/** '{B!6|"X
* @return ~^cMys |'
* Returns the hasNextPage. x]33LQ1]
*/ Cn[0(s6
publicboolean getHasNextPage(){ M4W5f#C5Ee
return hasNextPage; Rx+p.
} k]I0o)+O.
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/** /g4f`$a
* @param hasNextPage aT`%;i^
* The hasNextPage to set. 3Gip<\$v
*/ fS`$'BQ
publicvoid setHasNextPage(boolean hasNextPage){ gatB QwJb9
this.hasNextPage = hasNextPage; cA:*V|YV`
} "V}[':fen
ny54XjtG,
/** Ct%x&m:
* @return G2FXrkU
* Returns the hasPrePage. J^g!++|2P
*/ T|6a("RL
publicboolean getHasPrePage(){ &sd}ulEg`
return hasPrePage; G}G#i`6o
} j.@\3'
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/** z+>}RT]
* @param hasPrePage WH\))y-
* The hasPrePage to set. VzKW:St
*/ 10U9ZC
publicvoid setHasPrePage(boolean hasPrePage){ Qg<(u?7N
this.hasPrePage = hasPrePage; .?hP7;hhI
} 1&U>,;]*
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/** BGu?<bET
* @return Returns the totalPage. a 7,C>%I
* AoI/n4T^
*/ g"> {9YE
publicint getTotalPage(){ # m *J&
return totalPage; :dqn h
} =i7`ek
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/** W}]%X4<#rN
* @param totalPage NSDv;|f
* The totalPage to set. _zwUE
*/ 'uxX5k/D@t
publicvoid setTotalPage(int totalPage){ )
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this.totalPage = totalPage; Ck|8qUz-
} L;f!.FX#
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} = MOj|NR [
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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 [bk?!0]aV
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个PageUtil,负责对Page对象进行构造: yu/`h5&*
java代码: |1>*;\o-
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/*Created on 2005-4-14*/ _Iv6pNd/
package org.flyware.util.page; }I2@%tt?
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import org.apache.commons.logging.Log; 9b*nLyYVz
import org.apache.commons.logging.LogFactory; 6<ZkJ:=
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/** b^$|Nz;
* @author Joa DY?Kfvef
* |Xk4&sDrK
*/ ]h5Yg/sms
publicclass PageUtil { YS%h^>I^
y)@[Sl>
privatestaticfinal Log logger = LogFactory.getLog :65~[$2
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(PageUtil.class); 5qP:/*+
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/** %GS(:]{n
* Use the origin page to create a new page #: [<iSk
* @param page Ch3jxgQY
* @param totalRecords U b* wuI
* @return uPl\I6k
*/ fL=~NC"
publicstatic Page createPage(Page page, int -B$2\ZE
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totalRecords){ 9AJ7h9L
return createPage(page.getEveryPage(), XnWr5-;
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page.getCurrentPage(), totalRecords); wLOB}ZMT
} 9^G/8<^^>
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/** <U\B!fO'
* the basic page utils not including exception gY8>6'~mS
!_cg\KU#
handler {R?U.eJW
* @param everyPage _ "VkGG
* @param currentPage e!=kWc
* @param totalRecords 4Q6mo/=H
* @return page d*%`!G
*/ &?yZv{
publicstatic Page createPage(int everyPage, int VQS~\:1
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currentPage, int totalRecords){ z3;*Em8Ir
everyPage = getEveryPage(everyPage); _zwG\I|Q
currentPage = getCurrentPage(currentPage); h9G RI
int beginIndex = getBeginIndex(everyPage, MfWyc_
T
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currentPage); d5gR"ja
int totalPage = getTotalPage(everyPage,
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totalRecords); @6]sNm
boolean hasNextPage = hasNextPage(currentPage, L$E{ycn
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totalPage); /Id%_,}Kb
boolean hasPrePage = hasPrePage(currentPage); [.uG5%fa
K8UP,f2
returnnew Page(hasPrePage, hasNextPage, %*0^0wz
everyPage, totalPage, 8Y7Q+p|O
currentPage, >^*+iEe
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beginIndex); 2
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} YLzx<~E4a
2-Ej4I~
privatestaticint getEveryPage(int everyPage){ VYk!k3qS
return everyPage == 0 ? 10 : everyPage; zIu
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}
7B\Vs-d
zPjHsulK
privatestaticint getCurrentPage(int currentPage){ 3GhRWB-U
return currentPage == 0 ? 1 : currentPage; !~rY1T~
} NP/Gn6fr
P<a)25be/
privatestaticint getBeginIndex(int everyPage, int jT]0WS-b
:6 Lx@
currentPage){ Yd=>K HVD
return(currentPage - 1) * everyPage; qfMo7e@6*
} [8*jw'W|[
^!<BQP7
privatestaticint getTotalPage(int everyPage, int L"4mL,
^5h]Y;tx
totalRecords){ ;E3>ay6m8
int totalPage = 0; <?riU\-]y
$4 S@
if(totalRecords % everyPage == 0) F.=2u"[*&
totalPage = totalRecords / everyPage; M$>1L
else 3 +G$-ru
totalPage = totalRecords / everyPage + 1 ; bj>v|#r^
=pS5uR~
return totalPage; fj;y}t1E]
} )W;o<:x3
4;0lvDD
privatestaticboolean hasPrePage(int currentPage){ )quM4=u'
return currentPage == 1 ? false : true; c*L0@Ak%
} DkvF 5c&
W"}M1o
privatestaticboolean hasNextPage(int currentPage, R |(q
,0~n3G
int totalPage){ Tk:h@F|B.|
return currentPage == totalPage || totalPage == =,_ +0M9
`OXpU,Z 6U
0 ? false : true; B1>/5hV}
} [d1mLJAR
&h^9}>rVjV
"NXB$a!:
} IDB+%xl#S
%'s>QF]'
-y8`yHb_
=E.t`x=
117EZg]O
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。 m
g4nrr\
V9{]OV%
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 S~;4*7+?:
1^7hf;|#g
做法如下: w&o&jAb-M
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 $Bs {u=+w
~M7y*'oY
的信息,和一个结果集List: =F]FP5V
java代码: S||}nJ0
3L_\`Ia9
GzI yP(U
/*Created on 2005-6-13*/ VcSVu
package com.adt.bo; \KQ71yqY
LWz&YF#T-
import java.util.List; /
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=/y]d<g
import org.flyware.util.page.Page; {f2S/$q
w[S pw<Z
/** 2(u,SQ
* @author Joa jB$IyQ;@
*/ tG9BfGF
publicclass Result { 'rO!AcdLU
WaVtfg$!
private Page page; 17oa69G
Q@<S[Qh[.
private List content; CF&6J$ZBgJ
z$/_I0[
/** \Zqng
* The default constructor naYrpK,.
*/ YaKeq5%y
public Result(){ :D%"EJ
super(); M<.d8?p )
} QS` PpyBkd
jV>raCK_
/** B8V>NvE~o
* The constructor using fields [y'f|XN
* A+"ia1p,}
* @param page bm?sbE
* @param content g*e
*/ 7hlO#PYZ
public Result(Page page, List content){ _aad=BrMK
this.page = page; k.vBj~xU
this.content = content; 7VqM$I
} /%}*Xh
njScz"L~
/** +e yc`J
* @return Returns the content. s:/8[(A
*/ 4'`{H@]tb
publicList getContent(){ ur$
_
return content; OWjk=u2Lz
} `e}bdj
aqRhh=iS
/** yp KUkH/
* @return Returns the page. RrX[|GLSJ
*/ 2ORNi,_I
public Page getPage(){ <lw`
3aa(
return page; j9?}j#@
} 5iz{op<$,
5!DBmAB
/** wQP^WzNE
* @param content .aAL]-Rj
* The content to set. u frW\X
*/ -xSA
public void setContent(List content){ ~]pE'\D7Ad
this.content = content; 6*B1 9+-
} [F0s!,P
z3&]%Q&
/** P7nc7a
* @param page h{HF8>u[
* The page to set. \6E|pbJ}x
*/ xO^:_8=&:
publicvoid setPage(Page page){ 3L833zL
this.page = page; e+$p9k~
} +$C4\$t
} 8jd;JPz@\
%W%9j#!aN
10<x.8fSP
-fwoTGlX
`x
l
2. 编写业务逻辑接口,并实现它(UserManager, <49K>S9O
{sihus#Q
UserManagerImpl) ?t/~lv
java代码: r@v,T8
K`iv c N"
p7veQ`yNc
/*Created on 2005-7-15*/ *BR~}1
i
package com.adt.service; ;>
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ORyE`h
import net.sf.hibernate.HibernateException; ohF JZ'
%_+2@\
import org.flyware.util.page.Page; M9V
q
-U18
rR9|6l
3
import com.adt.bo.Result; "uuVy$6C
2^mJ+v<
/** 9o;^[Ql-
* @author Joa -yE/f2PgQ
*/ QrB@cK]
publicinterface UserManager { ?WF/|/
]+|~cRQ9I
public Result listUser(Page page)throws S4^vpY
DeN
mL{B!Q
HibernateException; #w,Dwy
"^w]_^GD$d
}
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Bg&i63XL$$
/2UH=Q!x4E
:*ing
56+s~hG
java代码: Y?
x,
NLUT#!Gr
P|.] DJ
/*Created on 2005-7-15*/ /tP|b_7O
package com.adt.service.impl; BGOuDKz9C
v1BDP<qU2
import java.util.List; :"=ez<t
e\Y*F
import net.sf.hibernate.HibernateException; OUeyklw
RIb4!!',c
import org.flyware.util.page.Page; M)eO6oX|
import org.flyware.util.page.PageUtil; jX3,c%aQ5e
*of3:w
import com.adt.bo.Result; 9Wnn'T@Tl
import com.adt.dao.UserDAO; +?u~APjNN
import com.adt.exception.ObjectNotFoundException; HG+%HUO$
import com.adt.service.UserManager; ]bj&bk#
"OQ^U_
/** rs,2rSsg!
* @author Joa Qr^|:U!;[z
*/ 2q3+0Et8
publicclass UserManagerImpl implements UserManager { )Y2{_ bx4"
MS\>DW
private UserDAO userDAO; !G SV6
BybW)+~
/** 85n1eE
* @param userDAO The userDAO to set. .QA }u ,EN
*/ \hBG<nH{0
publicvoid setUserDAO(UserDAO userDAO){ NdL,F;^
this.userDAO = userDAO; 62 O.?Ij
} @2Z#x
j Dy-)2<
/* (non-Javadoc) .2%zC & ;
* @see com.adt.service.UserManager#listUser T(f/ ?_%
Po ZuMF
(org.flyware.util.page.Page) ebT:/wu,2
*/ ?Cl%{2omO
public Result listUser(Page page)throws |K.mP4CKY
2] zq#6ix
HibernateException, ObjectNotFoundException { A D1=[I3
int totalRecords = userDAO.getUserCount(); ( M7pT
if(totalRecords == 0) x|mqL-Q f
throw new ObjectNotFoundException Z @^9PQG$
J3n-`k8
("userNotExist"); Tav*+
page = PageUtil.createPage(page, totalRecords); H*[M\gN$
List users = userDAO.getUserByPage(page); 9?0^ap,T
returnnew Result(page, users); ``ou/Z
} vg3=8>#
_9=Yvc=
} &Q>k7L!
KVD8YfF
Zrvz;p@~
2
dAB-d:k
.v$D13L(o
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 N'g>MBdI
n}'=yItVL1
询,接下来编写UserDAO的代码: VO$
iNK
3. UserDAO 和 UserDAOImpl: 8ELCs<xI
java代码: sC='_h
@&1ZB6OCb:
l y(>8F
/*Created on 2005-7-15*/ AS\F{ !O
package com.adt.dao; c
)G3k/T5
4WJ.^ (
import java.util.List; qMLD)rL
dR"@`
import org.flyware.util.page.Page; jg.QRny^
Y8o)FVcyNy
import net.sf.hibernate.HibernateException; Qk,I^1w?7
7cTV?nc
/** w)Q0_2p.
* @author Joa Ed_N[I
*/ hnDBFQ{
publicinterface UserDAO extends BaseDAO { 13@|w1/Z
cUA7#1\T=
publicList getUserByName(String name)throws qWODs
Z@3i$8
HibernateException; .w0s%T,8}^
cUY`97bn
publicint getUserCount()throws HibernateException; M7@2^G]p
8DegN,?
publicList getUserByPage(Page page)throws r]b_@hT',
~S8* t~
HibernateException; CE/Xfh'44
mT.u0KUIy
} EL(nDv
BDR.AZ
8xccp4
3?1`D/
;*:Pw?'
java代码: R'C2o]
eD*A)
P;Ga4Q.
/*Created on 2005-7-15*/ MM(xk
package com.adt.dao.impl; X4 A<[&F/
q U]gj@R
import java.util.List; kzt(i Y_6
MP!d4
import org.flyware.util.page.Page; PX<J&rx
a=hxJ1O
import net.sf.hibernate.HibernateException; ~])t 6i
import net.sf.hibernate.Query; @Ub"5Fl4
80Gn%1A9
import com.adt.dao.UserDAO; g7OqX \
gK[YQXfTy
/** @te!Jgu{
* @author Joa .=X}cJ]`[
*/ EUN81F?
public class UserDAOImpl extends BaseDAOHibernateImpl $shoasSuI
:9^;Qv*
implements UserDAO { ,u`B<heoLU
{
S3ZeN,kZ
/* (non-Javadoc) L{h%f4Du#
* @see com.adt.dao.UserDAO#getUserByName vTlwRG=5
L#+q]j+
(java.lang.String) 1 D<_N
*/ J"=vE=
publicList getUserByName(String name)throws ^yyC
[Mz
wtH?
[>S;)
HibernateException { t.`@{R$hoA
String querySentence = "FROM user in class `bZ/haU}A
kw"SwdP5
com.adt.po.User WHERE user.name=:name"; >g+?Oebgw
Query query = getSession().createQuery Y#u}tE
d
%<an9WMF
(querySentence); 8]M_z:F7F
query.setParameter("name", name); "a8j"lPJ
return query.list(); r=X}%~_8X
} qoj$]
S"OR%
/* (non-Javadoc) "CUty"R8
* @see com.adt.dao.UserDAO#getUserCount() 1n:8s'\
*/ ?<(m
5Al7
publicint getUserCount()throws HibernateException { [^U#Qj)hL
int count = 0; lzYnw)Pv
String querySentence = "SELECT count(*) FROM 6P5Ih
?34 e-
user in class com.adt.po.User"; iVy7elT;R
Query query = getSession().createQuery YwZ
Z{+n
&Nczv"TM
(querySentence); \H=&`?
count = ((Integer)query.iterate().next !+L/Khw/C
]y,==1To
()).intValue(); rld67'KcE
return count; `eIenA
} rmE" rf
@>E2?CV
/* (non-Javadoc) 2ioQb`=
* @see com.adt.dao.UserDAO#getUserByPage Bh=u|8yxc
}T%}wdj
(org.flyware.util.page.Page) 4*e0 hWp
*/ ~ ; -! n;
publicList getUserByPage(Page page)throws B:!W$<
Z(Bp 0a
HibernateException { ~[\_N\rm
String querySentence = "FROM user in class jC7&s$>Q"g
u"d~!j1
com.adt.po.User"; AO=h
23ZI
Query query = getSession().createQuery *T~Ve;3h;
}MHCd)78b
(querySentence); mw='dFt
query.setFirstResult(page.getBeginIndex()) $ep.-I>
.setMaxResults(page.getEveryPage()); {|1Y:&M?
return query.list();
^V#@QPK9
} lsy?Ac
GQ9\'z#+
} 1$%V{4bJ
^sVX)%
76Vl6cPu>
Er+nk`UR_
,ztI,1"k
至此,一个完整的分页程序完成。前台的只需要调用 ?ON-+u
!-,t'GF(
userManager.listUser(page)即可得到一个Page对象和结果集对象 FvJd8kV
EpFQ|.mQ
的综合体,而传入的参数page对象则可以由前台传入,如果用 WC|.g,9#
gMaN)ESqd4
webwork,甚至可以直接在配置文件中指定。 U5He?
Q)LM-ZJKQ
下面给出一个webwork调用示例: hED=u/ql[
java代码: 2EfF=Fm>
S6AU[ASY.
`~ * @q!
/*Created on 2005-6-17*/ aEWWFN
package com.adt.action.user; 4( 1(e
SL;9Q[
import java.util.List; .] sf0S!
rwG CUo6Z
import org.apache.commons.logging.Log; 86\S?=J-b
import org.apache.commons.logging.LogFactory; U)o$WH.b
import org.flyware.util.page.Page; U
)l,'y2
e{v=MxO=S
import com.adt.bo.Result; Fm #w2o
import com.adt.service.UserService; JM\m)RH0
import com.opensymphony.xwork.Action; ^1L>l9F
])Qs {hs~s
/** |"9 #bU
* @author Joa i}o[- S4
*/ ! ykx^z
publicclass ListUser implementsAction{ 9$|Gfyv
]- 4QNc=
privatestaticfinal Log logger = LogFactory.getLog
NsJ(`zk:
a(v>Q*zNP
(ListUser.class); !}r%
u."
NN1$'"@NL
private UserService userService; 6+KHQFb&N
X_g 3rv1J
private Page page; I=.z+#Y
8G5m{XTS(
privateList users; e&qh9mlE
^4`Px/&
/* =@8H"&y`
* (non-Javadoc) hQDTS>U
* i![dPM
* @see com.opensymphony.xwork.Action#execute() (>I`{9x>6
*/ l+g9 5mjP
publicString execute()throwsException{ y(=#WlK}
Result result = userService.listUser(page); L0tAgW!@
page = result.getPage(); 3neIR@W
users = result.getContent(); &g~ wS@
return SUCCESS; KhW;RD
} }GZ}Q5
`p7&>
BOA
/** K%Rj8J7|u?
* @return Returns the page. {nvLPUL
*/ GKFq+]W
public Page getPage(){ (<Th=Fns?
return page; jvV9eA:zl
} +ke1Cn'[
W!"}E%zx
/** Xj5~%DZp
* @return Returns the users. 0`I-2M4F*Q
*/ Iy.rqc/86
publicList getUsers(){ Z KOXI%~Mc
return users; {vN}<f`
} YNBHBK4;
,s_T pq
/** OHflIeq#@
* @param page $Tb G+Eb8
* The page to set. a<A+4uXyD
*/ L:k9#6
publicvoid setPage(Page page){ ph#tgLJ
this.page = page; `)Z!V?&