Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 B~^MhX
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 25BW/23}e
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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 %P0dY:L~
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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 7Gnslp?[U
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分页支持类:
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java代码: H/Cv ?GJF
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package com.javaeye.common.util; Bwjd/id q
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import java.util.List; !CtY.Lp
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publicclass PaginationSupport { nQdNXv<(
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publicfinalstaticint PAGESIZE = 30; '!Ps4ZTn_
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privateint pageSize = PAGESIZE; MVg`6&oH
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privateList items; X_C9Z
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privateint totalCount; N#@xo)-H
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privateint[] indexes = newint[0]; DBAJkBs
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privateint startIndex = 0; z{d] ,M
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public PaginationSupport(List items, int C, n]9
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totalCount){ uYIw ?fXy
setPageSize(PAGESIZE); 1)/B V{n
setTotalCount(totalCount); kMKI=>s+
setItems(items); uEWW Y t
setStartIndex(0); ?Pw#!t
} {k1s@KXtd
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public PaginationSupport(List items, int jz't!wj
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totalCount, int startIndex){ J9)wt ?%j
setPageSize(PAGESIZE); =vT3SY
setTotalCount(totalCount); n}
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setItems(items); :>nk63V (
setStartIndex(startIndex); ioi0^aM
} VxjEKc
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public PaginationSupport(List items, int h#zx^F1
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totalCount, int pageSize, int startIndex){ I|RN/RVN
setPageSize(pageSize); !s.G$ JS<
setTotalCount(totalCount); j$T2ff6
setItems(items); -le:0NUwI
setStartIndex(startIndex); LnZ*,>1Z
} /4#.qq0\{c
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publicList getItems(){ j:"+/5rV8
return items; }!0,(<EsV
} e~$MIHBY]
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publicvoid setItems(List items){ H|0B*i@81
this.items = items; <E$P
} +6*oO|
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publicint getPageSize(){ 6ecr]=Cv
return pageSize; KZ ?<&x
} 6Kh:m-E9
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publicvoid setPageSize(int pageSize){ tH5f;mY,
this.pageSize = pageSize; \@pl:Os
} 00U8<~u
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publicint getTotalCount(){ T=VVK6Lc:
return totalCount; )jR:\fe
} vMzR3@4e
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publicvoid setTotalCount(int totalCount){ YM3oqS D
if(totalCount > 0){ s.1(- "DU
this.totalCount = totalCount; ;s"m*
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int count = totalCount / u):z1b3*?
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pageSize; qw%4j9}
if(totalCount % pageSize > 0) NxNR;wz>l
count++; @MtF^y
indexes = newint[count]; hz Vpv,|G
for(int i = 0; i < count; i++){ PHDKx+$
indexes = pageSize * s[nOB0
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i; cIl^5eE^Pq
} `!qWHm6I*
}else{ ?-#w [J'6
this.totalCount = 0; j0=`Jf
} wa<@bub
} )#ic"UtR
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publicint[] getIndexes(){ m %ET!+
return indexes; &lBfW$PZjk
} |xQj2?_z*
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publicvoid setIndexes(int[] indexes){ v6s8 p
this.indexes = indexes; ?j8CkqX!
} 1Na CGD"
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publicint getStartIndex(){ t@}<&{zk
return startIndex; ~rpYZLH/:0
} GaRL]w
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publicvoid setStartIndex(int startIndex){ F__DPEAc_
if(totalCount <= 0) WHbvb3'
this.startIndex = 0; ?aSL'GI
elseif(startIndex >= totalCount) Lrq+0dI 65
this.startIndex = indexes jt3s;U*
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[indexes.length - 1]; p*Q"<@n
elseif(startIndex < 0) @#VxjXW^
this.startIndex = 0; M*t@Q|$:
else{ E'XFn'
this.startIndex = indexes e{=7,DRH<
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[startIndex / pageSize]; J'@I!Jc
} <+_OgF1G
} B'yN &3
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publicint getNextIndex(){ r+m8#uR
int nextIndex = getStartIndex() + q n =6>wP
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pageSize; @sfV hWG
if(nextIndex >= totalCount) \VtCkb
return getStartIndex(); uAVV4)
else F{l,Tl"Jw
return nextIndex; ~p'/Z@Atu
} ]PUyX8'~
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publicint getPreviousIndex(){ yaR|d3ef?4
int previousIndex = getStartIndex() - ik&loM_
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pageSize; @Z3b^G[
if(previousIndex < 0) 6K`frt
return0; 7acAU{Rr
else ,wX/cUyZ
return previousIndex; OE4 2{?)
} +"'h?7'C
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} #7Qn\C2
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抽象业务类 `awk@
java代码: QZh8l-!#5
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/** r\Man'h$
* Created on 2005-7-12 WqYl=%x"{V
*/ {_k 6 t
package com.javaeye.common.business; {tWfLfzU
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import java.io.Serializable; l l&iMj]
import java.util.List; WU=Os8gR
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import org.hibernate.Criteria; _e`b^_
import org.hibernate.HibernateException; bE0S)b)
import org.hibernate.Session; nH[@EL
import org.hibernate.criterion.DetachedCriteria; z#,?*v
import org.hibernate.criterion.Projections; }O
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import Oh8;YE-%
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org.springframework.orm.hibernate3.HibernateCallback; s[xdID^3.
import 60`y= !?f
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org.springframework.orm.hibernate3.support.HibernateDaoS a2).Az
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upport; &3u*
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import com.javaeye.common.util.PaginationSupport; v{%2`_c
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public abstract class AbstractManager extends *RuUf
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HibernateDaoSupport { /jS
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privateboolean cacheQueries = false; {BKI8vy
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privateString queryCacheRegion; [=LQ,e$r7
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publicvoid setCacheQueries(boolean 2RM0ca_F
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cacheQueries){ @8/-^Rh*
this.cacheQueries = cacheQueries; 0|4XV{\qT$
} 66z1_lA
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publicvoid setQueryCacheRegion(String Rjh/M`|
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queryCacheRegion){ #>>-:?X
this.queryCacheRegion = =&}dP%3LC)
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queryCacheRegion; yYF80mnJz
} ;PLby]=O
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publicvoid save(finalObject entity){ /B1NcRS
getHibernateTemplate().save(entity); r--"JO%2
} \&W~nYXq"
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publicvoid persist(finalObject entity){ [kC-g @
getHibernateTemplate().save(entity); y;Dw%m
} tSQ>P -O
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publicvoid update(finalObject entity){ E@[`y:P
getHibernateTemplate().update(entity); eb+[=nmP
} Jh }3AoD
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publicvoid delete(finalObject entity){ O<o_MZN
getHibernateTemplate().delete(entity); [>6:xGSe9X
} 'z+8;g.ekO
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publicObject load(finalClass entity, }0f[x ?V
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finalSerializable id){ =_v_#;h&
return getHibernateTemplate().load T.&^1q WWA
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(entity, id); 8|i&Gbw+
} &WsDYov?
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publicObject get(finalClass entity, Y{2\==~
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finalSerializable id){ -
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return getHibernateTemplate().get ZM4q@O)/
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(entity, id); lm@<i4%$F
} ^#"!uCq]gM
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publicList findAll(finalClass entity){ E#_}y}7JY
return getHibernateTemplate().find("from zFv>'1$
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" + entity.getName()); {mueP6Gz@J
} (obeEH5J
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publicList findByNamedQuery(finalString P_i2yhpK
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namedQuery){ cty.)e=
return getHibernateTemplate >F@7}Y(
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().findByNamedQuery(namedQuery); X"'}1o
} j7O7P+DmS
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publicList findByNamedQuery(finalString query, i}M&1E
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finalObject parameter){ i' N
return getHibernateTemplate z!t&zkAK
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().findByNamedQuery(query, parameter); t5e% "}>7H
} XlB`Z81j
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publicList findByNamedQuery(finalString query, O7q-MeMM
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finalObject[] parameters){ xB
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return getHibernateTemplate &.Yh_
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().findByNamedQuery(query, parameters); +mV4Ty
} qb
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publicList find(finalString query){ v#D9yttO{
return getHibernateTemplate().find SAXjB;VH6
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(query); ,uuQj]Dac+
} 0UlaB
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publicList find(finalString query, finalObject D<Ads
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parameter){ o-7>^wV%BD
return getHibernateTemplate().find Z.VVY\
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(query, parameter);
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} %VSST?aUvX
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public PaginationSupport findPageByCriteria g4%x7#vz0
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(final DetachedCriteria detachedCriteria){ jskATA
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return findPageByCriteria J%D'Xlb
d) G7U$z~
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 4$ejJaE
} "hpK8vQ
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public PaginationSupport findPageByCriteria aI+:rk^
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(final DetachedCriteria detachedCriteria, finalint rN}{v}n
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startIndex){ 0B1*N_.L@
return findPageByCriteria >iWl-hI-
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(detachedCriteria, PaginationSupport.PAGESIZE, jlzqa7
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startIndex); Alh%Z\
} 3vmLftZE}
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public PaginationSupport findPageByCriteria -\AB!#fh
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, U}7$:hO"dX
finalint startIndex){ ma?569Z8~0
return(PaginationSupport) pk(<],0]X
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getHibernateTemplate().execute(new HibernateCallback(){ >RE&>T^8
publicObject doInHibernate <k}>eGn
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(Session session)throws HibernateException { kw|bEL9!u
Criteria criteria = <hQ@]2w$
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detachedCriteria.getExecutableCriteria(session); uZ%b6+(
int totalCount = 6"eGd"
=@V4V} ?
((Integer) criteria.setProjection(Projections.rowCount ~SP.&>Q>
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()).uniqueResult()).intValue(); x\;`x$3t
criteria.setProjection O)&xT2'J
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(null); JL2IVENWc
List items = @5Ril9J[b
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criteria.setFirstResult(startIndex).setMaxResults 7^as~5'&-
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(pageSize).list(); 44RZk|U1J{
PaginationSupport ps = mmr>"`5.
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new PaginationSupport(items, totalCount, pageSize, QRw306
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startIndex); {Am\%v\
return ps; 8p>%}LX/
} htlsU*x
}, true); ,N<;!6e
} ~ $!eB/6ty
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public List findAllByCriteria(final &g.w~KWa
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)
DetachedCriteria detachedCriteria){ ^=E4~22q
return(List) getHibernateTemplate u#la+/
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().execute(new HibernateCallback(){ -!(3fO:
publicObject doInHibernate \9@*Jgpd6*
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(Session session)throws HibernateException { VlXIM,
Criteria criteria = Z]uN9c
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detachedCriteria.getExecutableCriteria(session); bq<QUw=]q&
return criteria.list(); "p2 $R*ie
} v#YO3nD
}, true); 1}KNzMHk9
} (3c,;koRR
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public int getCountByCriteria(final @Mt6O_V
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DetachedCriteria detachedCriteria){ REnRpp$
Integer count = (Integer) ^X"G~#v=q
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getHibernateTemplate().execute(new HibernateCallback(){ Q3wD6!'&m
publicObject doInHibernate C<6u}czA
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(Session session)throws HibernateException { /$&~0pk
Criteria criteria = a%*W^R9Ls
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detachedCriteria.getExecutableCriteria(session); 3`IDm5
return !ssE >bDa
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criteria.setProjection(Projections.rowCount .eK1xwhJ
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()).uniqueResult(); 4h:Oo
} G/2@Mn-
}, true); m*CIbkDsZ
return count.intValue(); VGWqy4m
} ,'={/)c<
} =h5&\4r=
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用户在web层构造查询条件detachedCriteria,和可选的 %jqBYn0q'
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ~k|~Q\
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PaginationSupport的实例ps。 N!9DZEcm
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ps.getItems()得到已分页好的结果集 ZJ=-cE2n
ps.getIndexes()得到分页索引的数组 |K aXek
ps.getTotalCount()得到总结果数 cS4e}\q,
ps.getStartIndex()当前分页索引 :NA cad
ps.getNextIndex()下一页索引 <kPU*P,
ps.getPreviousIndex()上一页索引 C.%iQx`
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 q,QMvUK:
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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 i3rvDch
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一下代码重构了。 JEU?@J71O
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我把原本我的做法也提供出来供大家讨论吧: D'|#5>G
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首先,为了实现分页查询,我封装了一个Page类: F{bET
java代码: .fUqsq
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/*Created on 2005-4-14*/ isQ{Xt~K
package org.flyware.util.page; X7NRQ3P@
',*I=JW;
/** (^eE8j/K
* @author Joa vh
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* }\*dD2qNL}
*/ czdNqk.kh
publicclass Page { 0O!%NL[,
ib/&8)Y+J
/** imply if the page has previous page */ 5p
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privateboolean hasPrePage; O0WzDD
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/** imply if the page has next page */ qGl+KI
privateboolean hasNextPage; vb5tyY0c
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/** the number of every page */ wgkh}b
privateint everyPage; Ju)2J?Xs5
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/** the total page number */ 9)aXLM4Y
privateint totalPage; 6LNm>O
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/** the number of current page */ U/D\N0
privateint currentPage; A~h.,<+"
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/** the begin index of the records by the current `"A\8)6-
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query */ x4.-7%VV%
privateint beginIndex; nDui9C
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/** The default constructor */ S>*i^If
public Page(){ i?4vdL8M
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} VSms hld
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/** construct the page by everyPage ldI;DoE#U1
* @param everyPage G?'L1g[lc
* */ }4A+J"M4y
public Page(int everyPage){ m`4Sp#m
this.everyPage = everyPage; M6pGf_qt
} {hZ_f3o
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/** The whole constructor */ $LF zpg
public Page(boolean hasPrePage, boolean hasNextPage, @"'1"$
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int everyPage, int totalPage, ,t*#o&+
int currentPage, int beginIndex){ fo4j^,`
this.hasPrePage = hasPrePage; VAsaJ`vcb
this.hasNextPage = hasNextPage; 'WxcA)z0cQ
this.everyPage = everyPage; l_ >^LFOA
this.totalPage = totalPage; 8yB
this.currentPage = currentPage; ;u!>( QQ
this.beginIndex = beginIndex; uJF,:}qA
} HMrS::
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/** Tx`;y|
* @return "eZNci
* Returns the beginIndex. z)]_ (zZ^
*/ +\\,FO_
publicint getBeginIndex(){ JV(|7Sk
return beginIndex; ;}=v|Dr&I.
} A4Q8^^byY
**fJAANc
/** $-jj%x\}
* @param beginIndex <M7@JgC &
* The beginIndex to set. EAj2uV
*/
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publicvoid setBeginIndex(int beginIndex){ T$0//7$')
this.beginIndex = beginIndex; ,]y)Dy
} 0rsdDME[
R l^ENrv!]
/** 3oE *86
* @return najd~%?Rs
* Returns the currentPage. v?-pAA)ht
*/ m~(]\
publicint getCurrentPage(){ Rkw)IdB
return currentPage; Y>R|Uf.o z
} -81usu&NH
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/** V78QV3
* @param currentPage O}Fp\"
* The currentPage to set. lRZt))3
*/ P7 H-Dw
publicvoid setCurrentPage(int currentPage){ z )a8
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this.currentPage = currentPage; ]y2(ZTNTs
} R1 hb-
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/** R1{"
* @return sn}U4=u
* Returns the everyPage. -KCm#!
*/ N&-d8[~
publicint getEveryPage(){ >e>Q'g{
return everyPage; /V$[M
} UStZ3A'
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/** UyEyk$6SU
* @param everyPage N6Vn/7I5%
* The everyPage to set. 6AUXYbK,
*/ XB50>??NE
publicvoid setEveryPage(int everyPage){ )?K3nr
this.everyPage = everyPage; df&d+jY
} :G9.}VrU
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/** Tm.(gK
* @return .B6$U>>NS^
* Returns the hasNextPage. _^0yE_ili
*/ 5owUQg,W
publicboolean getHasNextPage(){ Q/1
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return hasNextPage; M$FQoRwH
} OzA"i y
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/** wHx1CXC
* @param hasNextPage u/hFf3
* The hasNextPage to set. &b i Bm
*/ lJ62[2=V
publicvoid setHasNextPage(boolean hasNextPage){ '2WYbcU
this.hasNextPage = hasNextPage; `N_N zH
} o/CSIvz1
;Tvy)*{
/** _E{SGbCCi
* @return J&@[=zBYw
* Returns the hasPrePage. S5-}u)XnH
*/ AVZ -g/<
publicboolean getHasPrePage(){ xD8x1-
return hasPrePage; n,wLk./`
} dp&4G6Y<A
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/** V2u^sy
* @param hasPrePage Y(m/E.h.~
* The hasPrePage to set. Y@Lv>p
*/ 7 1z$a
publicvoid setHasPrePage(boolean hasPrePage){ zEl@jK,{$
this.hasPrePage = hasPrePage; (=j]fnH?
} 8;5 UO,`T
ullq}}
/** ";J1$a
* @return Returns the totalPage. 7;dV]N
* {[m %1O1
*/ 94 H\,}i8
publicint getTotalPage(){ _WVeb}
return totalPage; Ja4O*C<
} THi*'D/
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/** N>z_uPy{A
* @param totalPage zRx-xWo
* The totalPage to set. [@eNb^R
*/ pa~.[cBI
publicvoid setTotalPage(int totalPage){ B+ud-M0
this.totalPage = totalPage; $-|`#|CBd
} VuN=
JX
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} ^*C8BzcH
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 V&-pgxf;
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个PageUtil,负责对Page对象进行构造: %?' jyK
java代码: ;_@u@$=~
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*
/*Created on 2005-4-14*/ ]S[M]-I
package org.flyware.util.page; 6#MIt:#
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import org.apache.commons.logging.Log; .RxH-]xk
import org.apache.commons.logging.LogFactory; V2W)%c'
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/** <{Wsh#7 }.
* @author Joa *[]7l]XK.
* ryy".'v
*/ ArDkJ`DE
publicclass PageUtil { 6+b!|`?l+
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privatestaticfinal Log logger = LogFactory.getLog [8EzyB>fH
5`53lK.C
(PageUtil.class); X-|Lg.s
/XEUJC4
/** h$)+$^YI
* Use the origin page to create a new page R3`!Xj#&M
* @param page )@Fuw*
* @param totalRecords 8%S5Fc#am
* @return tY-{uHW&h
*/ &> tmzlww
publicstatic Page createPage(Page page, int 8
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(, Il>cR4
totalRecords){ .uG|Vq1v
return createPage(page.getEveryPage(), 494"-F 6
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page.getCurrentPage(), totalRecords); w[~O@:`]<o
} HP}d`C5<R
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/** 6}ct{Q
* the basic page utils not including exception QCIH1\`jW
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handler "a
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* @param everyPage k\8]fh)J\7
* @param currentPage ln-+=jk
* @param totalRecords {x{e?c!
* @return page )EZ#BF<0|
*/ U6;,<-bL
publicstatic Page createPage(int everyPage, int g)c<\%
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currentPage, int totalRecords){ DUUQz:?{J
everyPage = getEveryPage(everyPage); >0z(+}]3z
currentPage = getCurrentPage(currentPage); e~w-v"'
int beginIndex = getBeginIndex(everyPage, 0Ah'G
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currentPage); &sleV5V
int totalPage = getTotalPage(everyPage, ,_?P[~1
{gT2G*Ed^Z
totalRecords); ^iAOz-H
boolean hasNextPage = hasNextPage(currentPage, #!(OTe L
6}zargu(;
totalPage); c193Or'6Y
boolean hasPrePage = hasPrePage(currentPage); MO|aN,
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returnnew Page(hasPrePage, hasNextPage, `./$hh
everyPage, totalPage, 4n_f7'GZg
currentPage, mcvd/
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beginIndex); VX0q!Q
} (!`TO{ !6P
j#mo Vq
privatestaticint getEveryPage(int everyPage){ 7<;87t]]
return everyPage == 0 ? 10 : everyPage; <RH2G
} is@8x!c
h8OmO5/H
privatestaticint getCurrentPage(int currentPage){ qP=4D
9 ]
return currentPage == 0 ? 1 : currentPage; J%]</J
} -8H0f-1
(`<X9w,
privatestaticint getBeginIndex(int everyPage, int !cS
A|C
C{AVV<
currentPage){ WfYu-TK*
return(currentPage - 1) * everyPage; faH113nc
} l>p S23
|t](4
privatestaticint getTotalPage(int everyPage, int /sVy"48-
}j9V0`Q
totalRecords){ d/oxRzk'L
int totalPage = 0; ,ND}T#yTR
+72[*_ <
if(totalRecords % everyPage == 0) xaiA2
totalPage = totalRecords / everyPage; gbF^m`A>%+
else $KDH"J
totalPage = totalRecords / everyPage + 1 ; e
lj] e
hn]><kaA
return totalPage; #'s}=i}y"C
} `j+[JMr
/sHWJ?`&/,
privatestaticboolean hasPrePage(int currentPage){ 4E\Jk 5co,
return currentPage == 1 ? false : true; h2M>4c
} :rr;9nMR[
)"SP >2}
privatestaticboolean hasNextPage(int currentPage, h:%L% Y9z
Y)="of
int totalPage){ U8Rko)
return currentPage == totalPage || totalPage == rq=D[vX\N(
?U3X,uv5J
0 ? false : true; (`%$Aa9J
} c!#DD;<Q
rfj>/?8!@
i%RN0UO^
} P,1[NW
`x%(
n@ g
VsLlPw{
aNn\URR
Y*oT(
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。 kC~\D?8E=
:f1Q0klwP
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 (vL-Z[M!
7ip$#pzo
做法如下: Qy!*U%tG'
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 yc ize2>q
&,vPZ,7l
的信息,和一个结果集List: FwD"Pc2
java代码: doeYc
Ci{,e%
GI:J9TS
/*Created on 2005-6-13*/ ~{-zj
package com.adt.bo; )8ub1,C
x""gZzJ$L
import java.util.List; )qxZHV
i n}N[
import org.flyware.util.page.Page; f;";P
2|Of$oMc
/** 3eOwy~
* @author Joa UvwO/A\Gv
*/ hRKAs
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publicclass Result { ZcT%H*Ib]9
!{hC99q6
private Page page; |/Q7 o1i
CVo2?ZQ
private List content; II=(>G9v
9Rz TC
/** 7-p9IFcA
* The default constructor J-Xw}|>@
*/ QPL6cU$&R
public Result(){ d"h*yH@
super(); CJ'pZ]\G
} `R\aNgCS}
"DWw]\xO](
/** ^o;f~6#17
* The constructor using fields vR;?~^{*s
* xV]eEOiLM
* @param page 55aJ=T
* @param content Y`secUg
*/ /E(319u_
public Result(Page page, List content){ mPhrMcL
this.page = page; Ab|
tE5%
this.content = content; ui_nvD:
} Q7<_>)e^
-)='htiU
/** J`uO~W"
* @return Returns the content. EMe3Xb
`
*/ 8 K7.; t1
publicList getContent(){ km%c0:
return content; '*`25BiQ
} w]<a$C8*y:
2.xA' \M
/** /&PRw<}>_o
* @return Returns the page. l+%2kR
*/ G6l:El&
public Page getPage(){ *<.{sx^Gk
return page; O7]p `Xi8
} j=&]=0F
Wc6Jgpl
/** uv&??F]/
* @param content !&8nwOG
* The content to set. Q~p)@[q
*/ QL_vWG-
public void setContent(List content){ {=Z xF
this.content = content; >v
sy P
} B~\mr{|u
](^$5Am
/** :>y?B!=
* @param page A }(V2
* The page to set. %9^^X6yLM
*/ [:vH_(|
publicvoid setPage(Page page){ 9FGe(t<
this.page = page; >#9f{
} H K]-QTEn
} F!N D
RB,`I#z1f
@ PboT1
/Qa'\X,f3
m'j]T/WF
2. 编写业务逻辑接口,并实现它(UserManager, ~2HlAU))<&
BVJ6U[h`
UserManagerImpl) ( o(, ;
java代码: }jfOs(Q]
xOKLc!J
n8FmIoZ&`
/*Created on 2005-7-15*/ <`PW4zSI
package com.adt.service; #![9QUvcf
jV}tjwq
import net.sf.hibernate.HibernateException; rAv)k&l
)U2cS\k'7n
import org.flyware.util.page.Page; y}\d]*5
Q+i
import com.adt.bo.Result; 55%j$f
$u ae8h
/** B IW?/^
* @author Joa =yR$^VSY
*/ .=kXO{>
publicinterface UserManager { |. ZYY(}
cs-wqxTX[$
public Result listUser(Page page)throws ?W27
h
qcmf*Yl:v
HibernateException; [.
rULQl
6d# 7
} =ws iC'
ZyJ-}[z
e>6NO
E"/r*C+T
/QgU!:e
java代码: 1M={8}3
l KdY!j"
yPn!1=-(
/*Created on 2005-7-15*/ B$\,l.hE
package com.adt.service.impl; ?z[k.l+6w
s7 789pR
import java.util.List; ZUA%ZkX=F
5#WyI#YNG
import net.sf.hibernate.HibernateException; ~zd+M/8
4#MPD
import org.flyware.util.page.Page; ,f[`C-\Q%
import org.flyware.util.page.PageUtil; 3*v&6/K
Gg,&~
jHib
import com.adt.bo.Result; mw!EDJ;'
import com.adt.dao.UserDAO; c}-WK*v
import com.adt.exception.ObjectNotFoundException; (O(X k+L
import com.adt.service.UserManager; ((AsZ$[S
M^6!{c=MIi
/** C/JFb zVx
* @author Joa ^e~m`R2fHh
*/ j,Vir"-)
publicclass UserManagerImpl implements UserManager { Fr|Ts>Kx
[YTOrN
private UserDAO userDAO; N!Q~?/!d
g[%iVZ
/** 5bZjW~d
* @param userDAO The userDAO to set. e,X{.NS
*/ yu.N> [=
publicvoid setUserDAO(UserDAO userDAO){ ~%D=\iE
this.userDAO = userDAO; =qNZ7>Qw
} o9JZ-biH
iD(+\:E
/* (non-Javadoc) j@guB:0
* @see com.adt.service.UserManager#listUser d1{%z\u
a
ExW3LM9(
(org.flyware.util.page.Page) Vz\?a8qQ<
*/ 3
{OZdl|
public Result listUser(Page page)throws !iHJ!
;;]^d_
HibernateException, ObjectNotFoundException { g,O3\jjQ
int totalRecords = userDAO.getUserCount(); }rKKIF^f\S
if(totalRecords == 0) .B? J@,
throw new ObjectNotFoundException 9x]yu6
a*N<gId
("userNotExist"); tB<2mjg
page = PageUtil.createPage(page, totalRecords); ?3t]9z
List users = userDAO.getUserByPage(page); BXxl-x
returnnew Result(page, users); !]l!I9
} $j"TPkW{M
qJZ:\u8oO
} OBp&64
*S?vw'n
abczW[\
RHj<t");
wc~k4B9"
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 R]xXG0
*B0
7-
询,接下来编写UserDAO的代码: +]*hzWbe
3. UserDAO 和 UserDAOImpl: |K11Woii
java代码: Y )](jU%o
0XLoGQ=
#*v:.0%
/*Created on 2005-7-15*/ NNTUl$
package com.adt.dao; 5n#@,V.O/
a'prlXr\4
import java.util.List; (q+EP(Q
M!Wjfq
^~
import org.flyware.util.page.Page; a(|,KWHn
J.g4I|{
import net.sf.hibernate.HibernateException; ,>vI|p,/G*
wS%j!|xhlV
/** M?3#XQDvD
* @author Joa 7eP3pg#
*/ 7zWr5U.
publicinterface UserDAO extends BaseDAO { zjlo3=FQX[
R;3T yn+
publicList getUserByName(String name)throws T!3_Q/~^r
E==vk~cz
HibernateException; w.9'TR
enw7?| (
publicint getUserCount()throws HibernateException; "<^]d~a_
C0#"U f
publicList getUserByPage(Page page)throws a?gziCmS?C
n1;y"`gHk
HibernateException; &LM ^,xx}
0<4Swj3s7
} m!H7;S-(
dZi?Z
+1(L5Do}
uHu (
k,M%"FLQ
java代码: |j>fsk~
Xx;4
0!(BbQnWI
/*Created on 2005-7-15*/ uNS ]n}
package com.adt.dao.impl; c_+y~X)i
dxwH C\"5
import java.util.List; jxdxIkAHZc
7O^'?L<C'
import org.flyware.util.page.Page; $=rLs)
HLp9_Y{X.
import net.sf.hibernate.HibernateException; /4_^'RB
import net.sf.hibernate.Query; HyX:4f|]'
rZSX fgfr
import com.adt.dao.UserDAO; [pgld9To
tw?\bB
/** |v?*}6:a
* @author Joa UW@BAj@^@
*/ qTd6UKg
public class UserDAOImpl extends BaseDAOHibernateImpl ,^d!K(xb
yG%<LP2p@f
implements UserDAO { W%.ou\GN^t
Rb=8(#
/* (non-Javadoc) hq[RU&\
* @see com.adt.dao.UserDAO#getUserByName dXvp-oi
kIlK"=
(java.lang.String) ;+W9EbY2
*/ ?RI&7699+
publicList getUserByName(String name)throws tM&;b?bJ[
LjOHlT'
HibernateException { DD(K@M
String querySentence = "FROM user in class .dStV6
wO&2S-;_K
com.adt.po.User WHERE user.name=:name"; !v`C-1}70
Query query = getSession().createQuery Zv8I`/4?
PRi3=3oF
(querySentence); Pcox~U/j
query.setParameter("name", name); $,v[<T`
return query.list(); oY$L
} (RtjD`e}
`x'vF#
/* (non-Javadoc) ZZJXd+Q}
* @see com.adt.dao.UserDAO#getUserCount() RxZ#`$F
*/ 5Rc^5Nv
publicint getUserCount()throws HibernateException { YR$)yl
int count = 0; 60`4
_Uy]_
String querySentence = "SELECT count(*) FROM 2-#:Y
lAcXi$pF
user in class com.adt.po.User"; JMa[Ulz
Query query = getSession().createQuery _# mo6')j
v7kR]HU[y
(querySentence); sKLH.@
count = ((Integer)query.iterate().next P
O{1u%P
RXDPT
()).intValue(); fvUD'sx
return count; #Lq{_Y
} ^%<t^sE
%C^%Oq_k
/* (non-Javadoc) /Wqx@#
* @see com.adt.dao.UserDAO#getUserByPage jj&4Sv#>
OalBr?^
(org.flyware.util.page.Page) 83ajok4E
*/ QoVRZ $!p
publicList getUserByPage(Page page)throws XA%a7Xtni
iH#b"h{w
HibernateException { 14,Pf`5Sz
String querySentence = "FROM user in class EE<^q?[3^
^Nu0+S
com.adt.po.User"; qauZ-Qoc9
Query query = getSession().createQuery QaMB=wVr
AHA4{Zu[
(querySentence); M zbs#v0
query.setFirstResult(page.getBeginIndex()) _P]!J~$5
.setMaxResults(page.getEveryPage()); ZJ7<!?6
return query.list(); xO<$xx
} (3;dtp>Xx
.}V&*-ep
} ,%a7sk<5k
.;'3Roi
t=;84lA
X%>Sio
EC6Q<&]Iw
至此,一个完整的分页程序完成。前台的只需要调用 Wveba)"$
ydyGPZt
userManager.listUser(page)即可得到一个Page对象和结果集对象 /#,3JU$w
C<?Huw4R0
的综合体,而传入的参数page对象则可以由前台传入,如果用 G\U'_G>
b35Z1sfD
j
webwork,甚至可以直接在配置文件中指定。 SB3=5"q
?<#2raH-
下面给出一个webwork调用示例: (DW[#2\.
java代码: ZSu0e%
xq2
,S
u?>]C6$
/*Created on 2005-6-17*/ vFL\O
package com.adt.action.user; <R?_Yjsw
h6Vm;{~
import java.util.List; jr9/
y+PiH
import org.apache.commons.logging.Log; -a}d
@&
import org.apache.commons.logging.LogFactory; D3>;X= 1
import org.flyware.util.page.Page; j+_pF<$f:
D =Pv:)*]
import com.adt.bo.Result; a V4p0s6ZZ
import com.adt.service.UserService; u*<G20~A
import com.opensymphony.xwork.Action; nnZ|oEF
DjX*2O
/** nsCat($)
* @author Joa c<8RRYs
*/ _(q|W3
publicclass ListUser implementsAction{ gDmwJr
Nm0kMq|h
privatestaticfinal Log logger = LogFactory.getLog zgdOugmmt_
{Y%X
(ListUser.class); "F*'UfOwrZ
'kD~tpZ
private UserService userService; a^*@j:[
#h 4`f
private Page page; ![v@+9
$1CAfSgKw
privateList users; G(puC4 "&
=HF||p@
/* c==` r
C
* (non-Javadoc) 6L~tUe.G
* gGiLw5o,
* @see com.opensymphony.xwork.Action#execute() u'?yc"d>#
*/ f&\v+'[p
publicString execute()throwsException{ 4gTD HQP
Result result = userService.listUser(page); }- Jw"|^W
page = result.getPage(); t^=6czk
users = result.getContent(); QDRgVP
return SUCCESS; ?T\m
V}
} "))G|+tz
0ang^v;q
/** %EZG2J jO)
* @return Returns the page. ?]fd g;?@
*/ 4DL;/Z:
public Page getPage(){ T4\F=iw4
return page; ^XV=(k;~bX
} !KUV,>L
XeaO,P
/** LDJ=<c!
* @return Returns the users. fR>(b?C
*/ 0YsC@r47wL
publicList getUsers(){ {-sy,EYcw
return users; >qJRpO
} k-LB %\p
Tm8c:S^uq)
/** yK +&1U2`
* @param page yTDlDOmV!
* The page to set. V}l>p?
*/ ("t;
2Mw
publicvoid setPage(Page page){ c1IK9X*
this.page = page; ])=k";76
} *q8L$D
{YCquoF
/** EHT5Gf
* @param users GdqT4a\S
* The users to set. oEHUb?(p
*/ NXvu}&H
publicvoid setUsers(List users){ 8F(_V qu
this.users = users; eZ]4,,m
} P5+FZzQ
Y&O<A8=8
/** I9ga8mG4-'
* @param userService XD5z+/F<"0
* The userService to set. _5^p+
*/ V`KXfY
publicvoid setUserService(UserService userService){ U@<>2
this.userService = userService; Ix,`lFbH
} xzFV]
} a.a5qwG
~M 6^%
djeax
G)b6Rit
y ?FKou'
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, %f.(^<Gu
eu(1bAfS&T
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 mbBd3y
)#9R()n!
么只需要: kfo, PrW`A
java代码: LI[ w?6B
A*BIudli
.c'EXuI7),
<?xml version="1.0"?> ~y+QL{P4~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork %C%~f{4
T`{W$4XS
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ,TTt<&c
OLc/Vij;
1.0.dtd"> {]~b^=qE$
uE~? 2G
<xwork> j+:q:6 =
-r_/b
<package name="user" extends="webwork- &eQF[8 ,
B
Mh949;
interceptors"> uhUC m
?]}1FP
<!-- The default interceptor stack name xBhfC!AK}
Nhv~f0
--> 7p&%0'BO1z
<default-interceptor-ref H4 }^6><V
~S)o('
name="myDefaultWebStack"/> B*A{@)_
0+b1R}!2
<action name="listUser" "Y9
*rL
0nS69tH
class="com.adt.action.user.ListUser"> T~UKWAKX}
<param RYDV60*O6
_f%Wk>A4
name="page.everyPage">10</param> =$UDa`}D
<result Kw}-<y
-Cwx %
name="success">/user/user_list.jsp</result> ZYo Wz(
</action> q&