Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 rmX*s}B
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Y)sB]!hx
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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 {A0jkU
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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 "ko*-FrQ
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分页支持类: 9\Jc7[b
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java代码: Z/ q6Q#
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package com.javaeye.common.util; ]Dq6XR
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import java.util.List; b Hr^_ogN
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publicclass PaginationSupport { cp`Jep<T
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publicfinalstaticint PAGESIZE = 30; Z@zo~*o
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privateint pageSize = PAGESIZE; ^*ZaqMA
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privateList items; "\o#YC
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privateint totalCount; fd'kv
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privateint[] indexes = newint[0]; ?X|)0o
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privateint startIndex = 0; cY5&1Shb~
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public PaginationSupport(List items, int X:W\EeH
; J W]b]
totalCount){ )E9!m
setPageSize(PAGESIZE); 2.v{W-D[
setTotalCount(totalCount); AU9C#;JD
setItems(items); jEBn"]\D
setStartIndex(0); oMbd1uus
} : s
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public PaginationSupport(List items, int kLgkUck8]
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totalCount, int startIndex){ aO1^>hy
setPageSize(PAGESIZE); =Y2 Rht
setTotalCount(totalCount); 4/(#masIL
setItems(items); eo]nkyYDP
setStartIndex(startIndex); FyEKqYl
} 1/-3m Po
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public PaginationSupport(List items, int nah?V"
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totalCount, int pageSize, int startIndex){ p/Ul[7A4e
setPageSize(pageSize); '4'Z
setTotalCount(totalCount); 0|AgmW_7
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setItems(items); yJ?=##
setStartIndex(startIndex); p"0#G&-
} 1
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publicList getItems(){ 0nt@}\j
return items; DtANb^
} !<];N0nt#
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publicvoid setItems(List items){ 9nAP%MA`
this.items = items; NJBSVCb
} beOMln+R
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publicint getPageSize(){ }c8nn
return pageSize; _^_3>}y5op
} :ts3_-cr
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publicvoid setPageSize(int pageSize){ T,!EL+o4
this.pageSize = pageSize; %"{P?V<-V
} Jr5S8c|"
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publicint getTotalCount(){ z6`0Uv~
return totalCount; &2W"4SE]6
} V?EX`2S
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publicvoid setTotalCount(int totalCount){ aU6l>G`w
if(totalCount > 0){ ]wid;<
this.totalCount = totalCount; kZ5#a)U<
int count = totalCount / ?s2-iuMPd
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pageSize; ST{Vi';}
if(totalCount % pageSize > 0) a_Xwi:e<
count++; .=eEuH
indexes = newint[count]; 7^i7U-A<A
for(int i = 0; i < count; i++){ 'HWl_M
indexes = pageSize * cX9o'e:C
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i; 3wfcGQn|sD
} 6xDk3
}else{ I(M/X/
this.totalCount = 0; 336ETrG^0
} =dQ[I6
} uGZGI;9f4
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publicint[] getIndexes(){ T7nI/y
return indexes; _*H Hdd5I
} r|l?2 eO~
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publicvoid setIndexes(int[] indexes){ 1%_RXQVG
this.indexes = indexes; i
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} Phi5;U!
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publicint getStartIndex(){ 4`8s]X
return startIndex; @XJ7ff&
} n$2oM5<
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publicvoid setStartIndex(int startIndex){ fnq 3ic"V
if(totalCount <= 0) ZiZ @3O6
this.startIndex = 0; nT?+^Ruc
elseif(startIndex >= totalCount) 9\EW~OgTu
this.startIndex = indexes Al?%[-u
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[indexes.length - 1]; c!E{fS P
elseif(startIndex < 0) *+rfRH]a
this.startIndex = 0; A O5&Y.A#
else{ |tAkv
this.startIndex = indexes ) p>Cf_[.
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[startIndex / pageSize]; f"Iui
} 'd2
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} <TVJ9l
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publicint getNextIndex(){ +.~K=.O)
int nextIndex = getStartIndex() + 6CFnE7TQf
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pageSize; 2,:{ 5]Q$
if(nextIndex >= totalCount) wn@~80)$
return getStartIndex(); 8=$X hC
else QKjn/%l"@
return nextIndex; GeJ}myD O
} s'yR2JYv
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publicint getPreviousIndex(){ /k/X[/WO
int previousIndex = getStartIndex() - m}z6Bbis 0
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pageSize; ^# #j
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if(previousIndex < 0) a]*{!V{$i
return0; x_~_/&X5
else z6)N![X
return previousIndex; UJ,vE}=_{
} oaQW~R`_
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} E"'u2jEG^
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抽象业务类 EmaS/]X[
java代码: -r,v3n
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/** MB;rxUbhe3
* Created on 2005-7-12 B>1,I'/$.
*/ |yz[mP*;o
package com.javaeye.common.business; FaCW +9B
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import java.io.Serializable; w)|9iL8
import java.util.List; 'yVe&5?
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import org.hibernate.Criteria; ;.AMP$o`(Y
import org.hibernate.HibernateException; 8Ygf@*9L4
import org.hibernate.Session; 3UXZ|!-
import org.hibernate.criterion.DetachedCriteria; g$NUu
import org.hibernate.criterion.Projections; L*4"D4V
import Gx$m"Jeq\
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org.springframework.orm.hibernate3.HibernateCallback; {X<g93
import j5D Cc,s
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org.springframework.orm.hibernate3.support.HibernateDaoS OCu_v%G0
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upport; FS5iUH+5
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import com.javaeye.common.util.PaginationSupport; "8%$,rG1&
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public abstract class AbstractManager extends wlP3 XF?
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HibernateDaoSupport { _`p-^I
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privateboolean cacheQueries = false; C-A?
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privateString queryCacheRegion; K !ILO
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publicvoid setCacheQueries(boolean `Kg!aN
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cacheQueries){ $gnrd~v4e
this.cacheQueries = cacheQueries; 4`"}0:t.
} :[+8(~| za
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publicvoid setQueryCacheRegion(String kSiyMDY-
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queryCacheRegion){ md<^x(h"<
this.queryCacheRegion = mS[``$Z\!
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queryCacheRegion; Q9AvNj>X
} k62s|VeU
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publicvoid save(finalObject entity){ ,+IFV
getHibernateTemplate().save(entity); S'^ q
} ;o'r@4^&$R
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publicvoid persist(finalObject entity){ (/nnN4\=
getHibernateTemplate().save(entity); DzMg^Kp
} 59{X;
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publicvoid update(finalObject entity){ .s>@@m-
getHibernateTemplate().update(entity); ,9d]-CuP;
} *Sdx:G~gp
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publicvoid delete(finalObject entity){ @.$-
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getHibernateTemplate().delete(entity); &xB*Shp,B
} w>cqsTq
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publicObject load(finalClass entity, SF-E>s!XL
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finalSerializable id){ x#3*C|A
return getHibernateTemplate().load u;
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(entity, id); O>+=cg
} UFT JobU
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publicObject get(finalClass entity, jZ-s6r2=
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finalSerializable id){ $%cHplQz5
return getHibernateTemplate().get i,^3aZwJ'
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(entity, id);
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} B(1-u!pz
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publicList findAll(finalClass entity){ q\?p' i
return getHibernateTemplate().find("from ~IW{^u
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" + entity.getName()); G3:!]}
} OFtf)cGE
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publicList findByNamedQuery(finalString aOd#f:{y
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namedQuery){ iii|;v]+
return getHibernateTemplate Z5(9=8hB/
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().findByNamedQuery(namedQuery); mj$Ucql
} X uE: dL?
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publicList findByNamedQuery(finalString query, 3%5YUG@
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finalObject parameter){ xE@/8h
return getHibernateTemplate So!=uYX
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().findByNamedQuery(query, parameter); TMMJ5\t2
} ;$&\:-6A#
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publicList findByNamedQuery(finalString query, siI%6Gn;
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finalObject[] parameters){ 9\hI:rI
return getHibernateTemplate w -o#=R_
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().findByNamedQuery(query, parameters); \\\8{jq
} s.bo;lk
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publicList find(finalString query){ YyxU/UnhG
return getHibernateTemplate().find K [DpH&
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(query); 2lsUCQI;
} $4xSI"+M%
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publicList find(finalString query, finalObject {,sqUq (
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parameter){ tjFX(;^[
return getHibernateTemplate().find V>T?'GbS
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(query, parameter); <$e|'}>A
} q 7%p3
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public PaginationSupport findPageByCriteria T8A(W
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(final DetachedCriteria detachedCriteria){ %\<b{x# G
return findPageByCriteria kd^H}k
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); SdYf^@%}F
} =${.*,o
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public PaginationSupport findPageByCriteria =D$ED^W
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(final DetachedCriteria detachedCriteria, finalint |~BnE
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startIndex){ 4Wiy2
return findPageByCriteria <v0`r2^S{-
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(detachedCriteria, PaginationSupport.PAGESIZE, rT[qh+KWe
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startIndex); qMJJB l
} 6E}9uwQ
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public PaginationSupport findPageByCriteria vO1; ;
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(final DetachedCriteria detachedCriteria, finalint `RnWh9
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pageSize, Ldjz-
finalint startIndex){ S/5QK(XLC)
return(PaginationSupport) 0h@FHw2d
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getHibernateTemplate().execute(new HibernateCallback(){ X-HE9PT.
publicObject doInHibernate k B>F(^
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(Session session)throws HibernateException { xW`y7Q }p
Criteria criteria = \Vf:/9^
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detachedCriteria.getExecutableCriteria(session); Z#d#n!Lz
int totalCount = v~Q'm1!O4\
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((Integer) criteria.setProjection(Projections.rowCount C")genMH
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()).uniqueResult()).intValue(); vt#;j;liG
criteria.setProjection ;yJ:W8U]+;
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(null); &+2l#3}
List items = 06pvI}
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criteria.setFirstResult(startIndex).setMaxResults !e|\1v'0
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(pageSize).list(); ls@]%pz.1d
PaginationSupport ps = (P)G|2=
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new PaginationSupport(items, totalCount, pageSize, xN-,gT'!
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startIndex); SQ>i:D;
return ps; ZUQ
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} >Wr%usNxc
}, true); d<a|dwAeh
} 1Nt
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public List findAllByCriteria(final C27:tyV
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DetachedCriteria detachedCriteria){ }S/i3$F0~
return(List) getHibernateTemplate 1]7gYNzV"
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().execute(new HibernateCallback(){ -G,}f\Cg
publicObject doInHibernate lxhb)]c
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(Session session)throws HibernateException { /d3Jd.l!
Criteria criteria = OT{"C"%5t
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detachedCriteria.getExecutableCriteria(session); ~ skp}g]
return criteria.list(); v=N?(6T
} 3xChik{
}, true); =j,WQ66r3
} F[jE#M=k
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public int getCountByCriteria(final
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DetachedCriteria detachedCriteria){ FO2e7p^Q
Integer count = (Integer) vQEV,d1
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getHibernateTemplate().execute(new HibernateCallback(){ P3_.U8g$r
publicObject doInHibernate $O%{l.-O
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(Session session)throws HibernateException { rpT.n-H>%A
Criteria criteria = L80(9Y^xn
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detachedCriteria.getExecutableCriteria(session); p>B2bv+L
return 8 t5kou]h
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criteria.setProjection(Projections.rowCount EA& 3rI>U)
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()).uniqueResult(); $m 4-^=
} Jxe+LG
}, true); ~K;QdV=YX
return count.intValue(); ":Dm/g
} y}odTeq
} 9@
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用户在web层构造查询条件detachedCriteria,和可选的 ?5C'9 V
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 rJ!cma
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PaginationSupport的实例ps。 UnhVppnex
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ps.getItems()得到已分页好的结果集 GShxPH{_j
ps.getIndexes()得到分页索引的数组 z5>I9R^q;
ps.getTotalCount()得到总结果数 H71sxek3
ps.getStartIndex()当前分页索引 Wc3z7xK1@
ps.getNextIndex()下一页索引 HK@ij,px
ps.getPreviousIndex()上一页索引
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 P49\A^5S!
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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 %M(RV_R+6
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一下代码重构了。
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我把原本我的做法也提供出来供大家讨论吧: 2xI|G
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首先,为了实现分页查询,我封装了一个Page类: `Fy-"Uf
java代码: (j:
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/*Created on 2005-4-14*/ >yBqi^aL
package org.flyware.util.page; 9j,g&G.K
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/** .w2 ID
* @author Joa .Mt3ec<
* TktH28tK
*/ R@vcS=m7
publicclass Page { kBu{ bxL
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/** imply if the page has previous page */ X\|!
privateboolean hasPrePage; Tg\bpLk0=
YDt+1Kw}D
/** imply if the page has next page */ y>^a~}Zq
privateboolean hasNextPage; G95,J/w
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/** the number of every page */ ^t;z;.g
privateint everyPage; ks'>?Dw
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/** the total page number */ xs$$fPAQ
privateint totalPage; n<I{x^!
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/** the number of current page */ _fGTTw(
privateint currentPage; cnv>&6a)
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/** the begin index of the records by the current %,$ n^{v
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query */ JAPr[O&
privateint beginIndex; _VtQMg|u
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/** The default constructor */ rqdwQ
public Page(){ \@LTXH.
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} bx@l6bpQ
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/** construct the page by everyPage qQ&uU7,#
* @param everyPage Cs'LrUB?=U
* */ ZL MH~cc
public Page(int everyPage){
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this.everyPage = everyPage; (\V
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} "q@m6fs
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/** The whole constructor */ Gr"CHz/
public Page(boolean hasPrePage, boolean hasNextPage, ?1e{\XW
;JW_4;-
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int everyPage, int totalPage, .n-#A
int currentPage, int beginIndex){ y8Va>ul"U
this.hasPrePage = hasPrePage; 7R+(3NU1A
this.hasNextPage = hasNextPage; 6b|?@
this.everyPage = everyPage; 8)i""OD@I
this.totalPage = totalPage; sV^:u^
this.currentPage = currentPage; d[ N1zQW
this.beginIndex = beginIndex; gEA SYIQ
} \bA Yic
Z:;}
/** C@rGa7
* @return R%E7 |NAG
* Returns the beginIndex. bS.w<V
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*/ DSGcxM+
publicint getBeginIndex(){ )G? qX.D
return beginIndex; d_RgKdR )k
} >t D=t8
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/** |@qw
* @param beginIndex &4#Zi.]
* The beginIndex to set. [,%=\%5
*/ l6viP}R
publicvoid setBeginIndex(int beginIndex){ 8xpplo8
this.beginIndex = beginIndex; xNP_>Qa~
} 7ubz7*
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/** vDy&sgS$<
* @return p7h#.m~Qu
* Returns the currentPage. WWT1= #"
*/ 5{Cz!ut;tE
publicint getCurrentPage(){ uOxHa>h
return currentPage; b}J%4Lx%m
} CSk]c9=
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/** *[Hrbln
* @param currentPage
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* The currentPage to set. #cbgp;,M{I
*/ S63Zk0(25
publicvoid setCurrentPage(int currentPage){ <v"o+
this.currentPage = currentPage; 8;PkuJR_]
} yNTd_XPL
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/** .
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* @return n|`3d~9$&
* Returns the everyPage. n ]ikc|
*/ rg/{5f
publicint getEveryPage(){ DwD$T%kF
return everyPage; b7Y g~Lw
} 74s{b]jN'-
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/** Cs $5Of(
* @param everyPage {]vD@)k
* The everyPage to set. >1y6DC
*/ ?ukw6T
publicvoid setEveryPage(int everyPage){ 1Pf(.&/9_
this.everyPage = everyPage; S_}`'Z )
} Cj5mM[:s
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/** t=_^$M,yr
* @return lQA5HzC\
* Returns the hasNextPage. w~'xZ?
*/ 9&Y@g)+2
publicboolean getHasNextPage(){ @Z)|_
return hasNextPage; \l+v,ELX=
} $ /VQsb
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/** Bx\&7|,x
* @param hasNextPage V0ze7tSG[f
* The hasNextPage to set. 8^mE<
*/ |rm elQ-
publicvoid setHasNextPage(boolean hasNextPage){ kmB!NxF>)F
this.hasNextPage = hasNextPage; !^J;S%MB:K
} ^E&PZA\,;
8$00\><r
/** -(VJ,)8t2
* @return ul{x|R
* Returns the hasPrePage. mh
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*/ jW/WG tz
publicboolean getHasPrePage(){ |diI(2w
return hasPrePage; qY_qS=H^
} yzK;
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/** t0)1;aBZ
* @param hasPrePage VK}4<u
* The hasPrePage to set. 8&<:(mAP
*/ rTD +7
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publicvoid setHasPrePage(boolean hasPrePage){ ?vXgHDs^T
this.hasPrePage = hasPrePage; gLiJ&H
} 6W1GvM\e
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/** WhPP4 #
* @return Returns the totalPage. tRjv-
* ]5Cr$%H=
*/ ,5DJ54B!
publicint getTotalPage(){ 4WT[(
return totalPage; ZR.k'
} !\4x{Wa]
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/** g` rr3jP
* @param totalPage =]5tYIU
* The totalPage to set. T:}Q3
*/ ~o}:!y
publicvoid setTotalPage(int totalPage){ PK\Z Rl
this.totalPage = totalPage; n.%QWhUB
} f}otIf
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} 3i^X9[.
F%>$WN#2
*D5 xbkH=.
blc?[ [,!
[-~pDkf:
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 Met?G0[
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个PageUtil,负责对Page对象进行构造: k
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java代码: 8NN+Z<
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/*Created on 2005-4-14*/ y:G%p3h)[
package org.flyware.util.page; ]uXJjS f
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import org.apache.commons.logging.Log; ZR>BK,
import org.apache.commons.logging.LogFactory; R >x d*A
;QI9 OcE@/
/** D
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* @author Joa p1N}2]e
* IQqUFP$8g
*/ F)3+IuY
publicclass PageUtil { lyn%r
+VwQ=[y]
privatestaticfinal Log logger = LogFactory.getLog hgU;7R,?ir
]jT}]9Q$
(PageUtil.class); fQ+whGB
x}G:n[B7_V
/** qs4jUm
* Use the origin page to create a new page )f?I{
* @param page !gh8 Qs
* @param totalRecords r$jWjb
* @return R%r
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*/ Tigw+2
publicstatic Page createPage(Page page, int 6St=r)_
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totalRecords){ xAmtm"
return createPage(page.getEveryPage(), S^O9}<2g
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page.getCurrentPage(), totalRecords); ^[<BMk
} Pnytox
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/** y)kxR
* the basic page utils not including exception y-<.l=6A
Nd8>p.iqO
handler
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* @param everyPage 8/e-?2l
* @param currentPage -CPtYG[s
* @param totalRecords 7x)Pt@c
* @return page jAJ='|[X\
*/
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publicstatic Page createPage(int everyPage, int 3Z*r#d$nh:
fA=Z):w
currentPage, int totalRecords){ O9ex=m `L
everyPage = getEveryPage(everyPage); 0`/G(ukO
currentPage = getCurrentPage(currentPage); ,dC.|P' `
int beginIndex = getBeginIndex(everyPage, x $uhkP
7# AIX],
currentPage); =D<0&M9C
int totalPage = getTotalPage(everyPage, ]545:)Q1
(\\;A?
totalRecords); *%xbn8
boolean hasNextPage = hasNextPage(currentPage, Y ^^4n$
4m*)("H
totalPage); XkI'm\W
boolean hasPrePage = hasPrePage(currentPage); Q)75?mn
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returnnew Page(hasPrePage, hasNextPage, xHgC':l(0
everyPage, totalPage, (p]FI# y
currentPage, ?Y"%BS+pt
161P%sGx2
beginIndex); MA
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} la[pA
TY8gB!^
privatestaticint getEveryPage(int everyPage){ 2w|5SK_
return everyPage == 0 ? 10 : everyPage; d4o
^+\
} $dfc@Fn^x
T//xxH]w-
privatestaticint getCurrentPage(int currentPage){ kn3w6]
return currentPage == 0 ? 1 : currentPage; RELNWr
} <4rnOQ:
p)biOG
privatestaticint getBeginIndex(int everyPage, int {-A|f
$dM_uSt
currentPage){ BN*:*cmUl
return(currentPage - 1) * everyPage; [f+wP|NKL
} K0w}l" )A
=O}I{dNKZV
privatestaticint getTotalPage(int everyPage, int ^0]0ss;##R
`gSMb
UgF
totalRecords){ Es>' N3A
z
int totalPage = 0; 6Bq_<3P_
5CK+\MK
if(totalRecords % everyPage == 0) A f'&, 1=q
totalPage = totalRecords / everyPage; ~5
6&!4
else )>@S8v,(
totalPage = totalRecords / everyPage + 1 ; ]_C"A
Pe`mZCd^
return totalPage; s;A7:_z#7
} a1pp=3Pd?~
8Lgt
privatestaticboolean hasPrePage(int currentPage){ UPtj@gtcY
return currentPage == 1 ? false : true; ~z^?+MgZ2
} .xIAep_
%ap(=^|5
privatestaticboolean hasNextPage(int currentPage, Y0(4]X \ey
1!uBzO6/$
int totalPage){ (xgw';g
return currentPage == totalPage || totalPage == ?]><#[?'L
x3n9|Uud
0 ? false : true; "B'c;0@q
} >0HH#JW
WK|5:V8E
.\_):j*
} /r4l7K
XFWpHe_ L
$;5Q
mKQ'
@i#JlZM_
V$ZclV2:Ih
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。 N.*)-O
Kq[4I[+R
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 I>?oVY6M@u
|]-Zz7N)
做法如下: q>_<\|?%x
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 mZ71_4X#
*RkUF!)(
的信息,和一个结果集List: k`5I"-e
java代码: 1(p:dqGS
Vh~hfj"
Snk+ZQ-
/*Created on 2005-6-13*/ $w(RJ/
package com.adt.bo; ?R]`M_^&u!
9a*#r;R
import java.util.List; ^kfqw0!
5W)ST&YPL*
import org.flyware.util.page.Page; Kk^*#vR
5G355 ,}E
/** biHacm
* @author Joa G*IP?c>=
*/ prZ
,4\
publicclass Result { g}MUfl-L
"Not /8J
private Page page; a&>NuMDI
QIiy\E%
private List content; h0<PQZJ
ROFZ*@CH<
/** <Yki8
* The default constructor 4Ly>x>b<
*/ vAX ( 3
public Result(){ uZ6krI
super(); ;<Q%d~$xy}
} 4&W?:=H2
mB-,\{)
/** 'xH^ksb "
* The constructor using fields `X<B+:>v-
* >Y>R1b%
* @param page 811>dVq3/
* @param content #gbB// <
*/ xr'1CP
public Result(Page page, List content){ @v2<T1UC
this.page = page; +gd5&
this.content = content; Ef] Hpjvp
} :|;@FkQ
%>FtA)
/** IV,4BQ$
* @return Returns the content. G(t:s5:
*/ 6qT@M0)i
publicList getContent(){ SES.&e|!6
return content; ?4':~;~
} CyIlv0fd}
m?kiGC&m
/** AM-bs^
* @return Returns the page. -PV1x1|
*/ x*Z'i<;B
public Page getPage(){ )9H5'Wh#
return page; dk&e EDvfd
} z>N[veX%
:7K
a4
/** Et3]n$
* @param content +Kk1[fh-
* The content to set. 0j@mzd2
*/ poBeEpbs
public void setContent(List content){ 6nTM~]5.
this.content = content; WJq>%<#
} c9+G
Qp
G[KjK$.Ts?
/** *?<N3Rr*
* @param page -+ByK#<%
* The page to set. j !*,(
*/ [oh06_rB
publicvoid setPage(Page page){ zA5nr`
this.page = page; e \Qys<2r
} F;Q,cg M
} s!(R
L3{(Bu
2Wzx1_D"a
HTh?&u\QG
>W> rhxU
2. 编写业务逻辑接口,并实现它(UserManager, }r,M(Zr
.\caRb[
UserManagerImpl) ]nsjYsT
java代码: D_lRYLA+
dWd%>9}
;g0s1nz
/*Created on 2005-7-15*/ rMwa6ZO'm;
package com.adt.service; jf3Zy:*K
t2,II\Kl
import net.sf.hibernate.HibernateException; 4K^cj2X
4o#]hB';ni
import org.flyware.util.page.Page; B_d\eD
t/[lA=0 )2
import com.adt.bo.Result; gC?}1]9c
k'iiRRM
/** J2qsZ
* @author Joa O&?i#@5#
*/ O1v)*&NAI
publicinterface UserManager { ExG(*[l
|:S6Gp[\O
public Result listUser(Page page)throws 2}&ERW
6La[( )
HibernateException; QVjHGY*R
^(JrOh'
} `%Fp'`ZM$8
OG}890$n
U =J5lo
(m3hD)!+y
;VLDXvGd
java代码: ^/#+0/Bn
G`l\R:Q
Lip#uuuXXN
/*Created on 2005-7-15*/ Ii+3yE@c
package com.adt.service.impl; $U[d#:]
1>e30Ri,g
import java.util.List; y11^q*}
Z 7@'I0;A
import net.sf.hibernate.HibernateException; nZioFE}
!*v%
s
import org.flyware.util.page.Page; OH@"]Nc~
import org.flyware.util.page.PageUtil; 44e]sT.B
ZFLmD|q#{
import com.adt.bo.Result; -f |/#1
import com.adt.dao.UserDAO; SNqSp.>-U"
import com.adt.exception.ObjectNotFoundException; 1NP
import com.adt.service.UserManager; _\>y[e["p
2mEqfy
/** x/<ow4C
* @author Joa mW{;$@PLF"
*/ N[
=I
publicclass UserManagerImpl implements UserManager { 0#NMNZ
Kyh6QA^
private UserDAO userDAO; dSwfea_
<4TI;yy6?
/** Y@ v][Q
* @param userDAO The userDAO to set. 0'd@8]|H
*/ Vs5 &X+k
publicvoid setUserDAO(UserDAO userDAO){ [6TI_U~
this.userDAO = userDAO; 3X(^`lAf)
} ZSNbf|ldiE
Vu(NP\Wm
/* (non-Javadoc) 6 :4GI
* @see com.adt.service.UserManager#listUser | +;ZC y
DG;u_6;JR
(org.flyware.util.page.Page) :kHk'.V1(
*/ lH3.q4D
5
public Result listUser(Page page)throws -=lm`X<:
b]]k\b
HibernateException, ObjectNotFoundException { .!~ysy
int totalRecords = userDAO.getUserCount(); a >fA-@
if(totalRecords == 0) .45wwouZkc
throw new ObjectNotFoundException 9,fV
Mzg'$]N
("userNotExist"); MNs<yQ9I'
page = PageUtil.createPage(page, totalRecords); ai;!Q%B#Q
List users = userDAO.getUserByPage(page); l]|&j`'O
returnnew Result(page, users); bpsyO>lx/
} G5qsnTxUJ
r^"o!,H9q
} :fmV||Q
MLr L"I"
.g/!u(iy
VQ!4(
<XD
m LajiZ Bf
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 o2(w
AkW,Fp1e
询,接下来编写UserDAO的代码: ANPG3^w
3. UserDAO 和 UserDAOImpl: :G#%+,
java代码: Y#lAG@$
8TYh&n=r
eQQVfEvS
/*Created on 2005-7-15*/ 8GxT!
package com.adt.dao; 0iSNom}m
ub 2'|CYw
import java.util.List; ;7Qe m&
xFUD9TM
import org.flyware.util.page.Page; @dQr^'h
Yy
4Was#
import net.sf.hibernate.HibernateException; "a(R>PV%
^Whc<>|
/** jEKa9rt
* @author Joa
=pe O%
*/ 9I 6^-m@:
publicinterface UserDAO extends BaseDAO { "^t7]=q
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publicList getUserByName(String name)throws 2^s@n3t
qb nlD\
HibernateException; 2;]tIt d1
lJa-O
publicint getUserCount()throws HibernateException; toF6 Z
'NWvQR<X
publicList getUserByPage(Page page)throws BfCib]V9C
AkjoD7.*
HibernateException; h1>.w
pr
,=!s;+lu{
} ZHen:
f~d=1
_BG`!3U+
)FB<gCh7X
Nt+UL/1]
java代码: R7Tl1!,h
fo}@B&=4
JBQ>"X^
/*Created on 2005-7-15*/ 5YZ\@<|rH
package com.adt.dao.impl; @W+8z#xr'
21$^k5
import java.util.List; w;VUP@Wm
m";8 nm
import org.flyware.util.page.Page; ~l+~MB
0T3r#zQ
import net.sf.hibernate.HibernateException; qyyLU@hd
import net.sf.hibernate.Query; i_6 wD
8Pom^QopK
import com.adt.dao.UserDAO; T5~Qfl?Y
#oGvxc7
/** "6$+B/5
* @author Joa g 'L$m|
*/ ^(xVjsHp#
public class UserDAOImpl extends BaseDAOHibernateImpl 7.5\LTM>9e
17Q*
<iCs
implements UserDAO { j@Us7Q)A(
Fo"'[`
/* (non-Javadoc) 0g#?'sD
* @see com.adt.dao.UserDAO#getUserByName /7*qa G
8HO)",+I
(java.lang.String) zJ0'KHF}o
*/ 8/34{2048
publicList getUserByName(String name)throws *7Sg8\wDn
gp'n'K]
HibernateException { gvZLW!={
String querySentence = "FROM user in class qfY=!|O
/|e"0;{
com.adt.po.User WHERE user.name=:name"; .>zkS*oX4z
Query query = getSession().createQuery 4ri)%dl1
9]8M {L
(querySentence); _Q;M$.[zyR
query.setParameter("name", name); S67T:ARS
return query.list(); a-TsD}'X
} zGFW?|o<
[TV"mA
/* (non-Javadoc) }\ui}\
* @see com.adt.dao.UserDAO#getUserCount() ^_Z Qf
*/ :kI
x?cc
publicint getUserCount()throws HibernateException { .uagD[${
int count = 0; d>4e9M"
String querySentence = "SELECT count(*) FROM B<'V7#L_
H+2J.&Ch
user in class com.adt.po.User"; PZA;10z
Query query = getSession().createQuery $j}sxxTT
e$(i!G)
(querySentence); 7 -V_)FK2c
count = ((Integer)query.iterate().next ~h[lu^ZSi
G@Zi3 5
()).intValue(); S+OI?QS
return count; ")M.p_b[Z=
} 1J*wW# e
Zk;;~ESOU
/* (non-Javadoc) kk5i{.?[
* @see com.adt.dao.UserDAO#getUserByPage 1}q[8q
vrW9<{
(org.flyware.util.page.Page) k0D&F;a%
*/ ow`c B
publicList getUserByPage(Page page)throws ;1OTK6
8QZk0O
HibernateException { z06pX$Q.<
String querySentence = "FROM user in class SS~Txt75m
fW}H##b
com.adt.po.User"; " Gn; Q-@
Query query = getSession().createQuery yZ)ScB^
't_=%^q
(querySentence); c!\y\r
query.setFirstResult(page.getBeginIndex()) $BBfsaJPT
.setMaxResults(page.getEveryPage()); gZ!(&u
return query.list(); x!.VWG tb
} FZ2-e
(&hX8
} 7<:w-
(1}Ndo^;w
`y6l^ep
m<f{7]fi5
d<b,LD^
至此,一个完整的分页程序完成。前台的只需要调用 hA\8&pI;
yRi/YR#
userManager.listUser(page)即可得到一个Page对象和结果集对象 Q#r 0DWo\
/eMZTh*1P
的综合体,而传入的参数page对象则可以由前台传入,如果用 =nL*/
@Q1jH~t
webwork,甚至可以直接在配置文件中指定。 jh0$:6 `C
nG*6ic
下面给出一个webwork调用示例:
]D-48o0
java代码: IFTW,9hh
YXg
uw7%\
eB@i)w?@o
/*Created on 2005-6-17*/ =K>Z{%i
package com.adt.action.user; y?@Y\ b
aC$g(>xFt
import java.util.List; 7VXeu+-P
835Upj>
import org.apache.commons.logging.Log; /[IQ:':^
import org.apache.commons.logging.LogFactory; h{xERIV1u
import org.flyware.util.page.Page; ?-84_i
XP^6*}H.*
import com.adt.bo.Result; 7~Ga>BK
import com.adt.service.UserService; yl ;'Ru:
import com.opensymphony.xwork.Action; ,"VQ0Z1
E\*",MGL
/** 9cmJD5OO
* @author Joa +?:V\niQI
*/ Z=c@Gd
publicclass ListUser implementsAction{ ge oN4
6qJB"_.
privatestaticfinal Log logger = LogFactory.getLog 66 Xt=US
|\(/dXXP
(ListUser.class); %UJ4wm
` ;=Se_
private UserService userService; #"{8Z&Z
piFQ7B
private Page page; e,*[5xQ
OA=;9AcZ
privateList users; 19u?^w
Aii[=x8
/* .KsvRx
* (non-Javadoc) FOA%(5$4
* Wu&Di8GhP
* @see com.opensymphony.xwork.Action#execute() u"gp">
*/ dR+$7N$
publicString execute()throwsException{ kZ9pgdI
Result result = userService.listUser(page); "\[>@_p h
page = result.getPage(); pzr-}>xrZ
users = result.getContent(); Pvw%,=41O
return SUCCESS; w$ {
} cj#q7
%$xFnGb
/** y)E2=JQA/
* @return Returns the page. ) :@%xoF5
*/ :GYv9OG
public Page getPage(){ s-V$N
return page; /6c10}f
} lpUtNy
P.B'Gh#^
/** 1F,_L}=o1s
* @return Returns the users. mD)O\.uA
*/ ix+x-G
publicList getUsers(){ i|^6s87"N2
return users; *~uuCLv_
} { bn#:75r
!?*!"S-Sl
/** Y%l3SB,5L
* @param page ~Wm}M
* The page to set. 5,ahKB8
*/ $SVGpEw
publicvoid setPage(Page page){ )+,jal^7
this.page = page; 9`{2 h$U
} Rk[ * p
9Ol_z\5
/** CM1a<bV<
* @param users `=DCX%Vw
* The users to set. 8|NJ(D-$
*/ "%t`I)
publicvoid setUsers(List users){ r_E)HL/A
this.users = users; Q$L(fHkw
} 8Jj0-4]
3]es$ Jy
/** ]?`p_G3O
* @param userService 7~nCK
* The userService to set. E0]h|/A]
*/ 34kd|!e,
publicvoid setUserService(UserService userService){ [B @j@&
this.userService = userService; ug"<\"
} \q'fB?bS^
} )N6[rw<