Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _^@ >I8ix
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &cZl2ynPi
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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 SsCV}[
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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 @iBaJ"*,
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分页支持类: fk2p}
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java代码: H(tT8Q5i
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package com.javaeye.common.util; 0b}.!k9
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import java.util.List; _)ZxD--Qg
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publicclass PaginationSupport { VQ8Q=!]
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publicfinalstaticint PAGESIZE = 30; 2= zw!
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privateint pageSize = PAGESIZE; gX]ewbPDQ
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privateList items; f~:wI9
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privateint totalCount; `+!F#.
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privateint[] indexes = newint[0]; u;9a/RI
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privateint startIndex = 0; 5;X r0f
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public PaginationSupport(List items, int [LM9^*sG2V
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totalCount){ C#TP1~6
setPageSize(PAGESIZE); C."\ a_p
setTotalCount(totalCount); ;:
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setItems(items); ldt]=Sqy
setStartIndex(0); t"?)x&dS
} $]gflAe2
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public PaginationSupport(List items, int (,D:6(R7t
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totalCount, int startIndex){ g(dReC
setPageSize(PAGESIZE); ej,R:}C%`
setTotalCount(totalCount); Y)2#\ F
setItems(items); (qzBy \\p
setStartIndex(startIndex); '7
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} 2
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public PaginationSupport(List items, int rV}&G!V_t
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totalCount, int pageSize, int startIndex){ 1 %8JMq\
setPageSize(pageSize); %D3Asw/5a
setTotalCount(totalCount); %Ix2NdC
setItems(items); Of>2 m<
setStartIndex(startIndex); 7Q9| P?&:z
} W5>emx'>
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publicList getItems(){ B Q2N_*v
return items; w+$~ds
} uH)?`I\zrd
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publicvoid setItems(List items){ o4jh n[Fx
this.items = items; pKU(4&BxX
} {DZ xK(
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publicint getPageSize(){ .DM-&P
return pageSize; 3vdFO: j
} QD-`jV3
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publicvoid setPageSize(int pageSize){ t N4-<6
this.pageSize = pageSize; dZX;k0
} gwr?(:?
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publicint getTotalCount(){ _bt9{@)
return totalCount; *c
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} z[@i=avPG
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publicvoid setTotalCount(int totalCount){ Eu<f
if(totalCount > 0){ ~n!&~
this.totalCount = totalCount; KTBtLUH]*F
int count = totalCount / 2A:&Cqo
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pageSize; &xZSM,
if(totalCount % pageSize > 0) P-<1vfThH
count++; 6)BPDfU,
indexes = newint[count]; UA(4mbz+
for(int i = 0; i < count; i++){ P- +]4\
indexes = pageSize * 5 D=r7
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} "$D'gSoYe
}else{ +v$W$s&b-h
this.totalCount = 0; :@a0h
} 9hssIZO
} RR'sW@
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publicint[] getIndexes(){ XE&h&v=>
return indexes; S^D7}
} Djdd|Z+*{
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publicvoid setIndexes(int[] indexes){ /Kq'3[d8
this.indexes = indexes; qHtIjtt[q
} K|OPtYeb
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publicint getStartIndex(){ Ji:<eRx)
return startIndex; :KR
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} O&&_)
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publicvoid setStartIndex(int startIndex){ qozvNJm)
if(totalCount <= 0) ?>iUz.];t
this.startIndex = 0; jVZ<i}h0B
elseif(startIndex >= totalCount) qVI0?B
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this.startIndex = indexes +95v=[t#Ut
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[indexes.length - 1]; Iqn
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elseif(startIndex < 0) ``I[1cC
this.startIndex = 0; SH#*Lc
else{ >\3\&[#"
this.startIndex = indexes d0C _:_
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[startIndex / pageSize]; +GL$[ 5G
} hvQXYo>TZx
} biBMd(6
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publicint getNextIndex(){ -%gEND-AP
int nextIndex = getStartIndex() + (vX<Bh
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pageSize; Xx%<rsA>F
if(nextIndex >= totalCount) `CC=?E
return getStartIndex(); yP>025o't
else Kd58'$
return nextIndex; B f]Bi~w<
} esQ$.L
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publicint getPreviousIndex(){ %+Y wzL{
int previousIndex = getStartIndex() - B2P@9u|9
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pageSize; "}`)s_rt
if(previousIndex < 0) 'P" i9j
return0; Hh*?[-&r~
else Ox&G
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return previousIndex; \!BVf@>p%
} QkW'tU\^
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} rQ_@q_B.
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抽象业务类 x: _[R{B
java代码: s</qT6@
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/** 5Gy#$'kdf
* Created on 2005-7-12 eh `%E0b}
*/ DyiJ4m}kh
package com.javaeye.common.business; \yFUQq:
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import java.io.Serializable; ,xVAJ6_#
import java.util.List;
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import org.hibernate.Criteria; S6JXi>n
import org.hibernate.HibernateException; RK &>!^
import org.hibernate.Session; \|HNFx T`
import org.hibernate.criterion.DetachedCriteria; Q
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import org.hibernate.criterion.Projections; iW>^'W#
import 9 %4:eTcp
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org.springframework.orm.hibernate3.HibernateCallback; y^`JWs,
import ]lBCK
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org.springframework.orm.hibernate3.support.HibernateDaoS PBCGC^0{
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upport; 3cL
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import com.javaeye.common.util.PaginationSupport; ">z3i`#C'
@|c])
public abstract class AbstractManager extends _7<{+Zzm
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HibernateDaoSupport { o?hr>b
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privateboolean cacheQueries = false; dM^Z,;u
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privateString queryCacheRegion; .Lna\Bv
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publicvoid setCacheQueries(boolean @|vH5Pi
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cacheQueries){ ]>VG}e~b
this.cacheQueries = cacheQueries; :1>?:3,`
} IUFc_uL@\
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publicvoid setQueryCacheRegion(String (jDz[b#OPz
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queryCacheRegion){ JN|6+.GG
this.queryCacheRegion = 5z!$=SFz
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queryCacheRegion; lbBWOx/|
} WqCC4R,-
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publicvoid save(finalObject entity){ aLGq<6Ja
getHibernateTemplate().save(entity); "a8E0b
} aIV
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publicvoid persist(finalObject entity){ TB!I
getHibernateTemplate().save(entity); P.,U>m
} M}V!;o<t^
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publicvoid update(finalObject entity){ 1*TbgxS~W
getHibernateTemplate().update(entity); ZP<<cyY
} LZRg%3.E
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publicvoid delete(finalObject entity){ o3 fc -
getHibernateTemplate().delete(entity); o[Jzx2A<
} P9
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publicObject load(finalClass entity, "%gsGtS
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finalSerializable id){ ukW&\
return getHibernateTemplate().load ,RV
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(entity, id); bP&QFc
} _qxI9Q}<"
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publicObject get(finalClass entity, Fz%;_%j
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finalSerializable id){ 8s0+6{vW
return getHibernateTemplate().get *|fF;-#v
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(entity, id); qz-QVY,
} dI{DiPho
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publicList findAll(finalClass entity){ Gmz^vpQ]t
return getHibernateTemplate().find("from &0F' Ca
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" + entity.getName());
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} }Y~Dk]*
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publicList findByNamedQuery(finalString FlBhCZ|^
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namedQuery){ Ttluh
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return getHibernateTemplate \CL8~
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().findByNamedQuery(namedQuery); Z}J5sifr
} b2m={q(s
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publicList findByNamedQuery(finalString query, a5D|#9
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finalObject parameter){ m8q4t,<J
return getHibernateTemplate u^"
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().findByNamedQuery(query, parameter); u "[f\l
} QNj]wm=mp
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publicList findByNamedQuery(finalString query, ^#9385
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finalObject[] parameters){ =&}@GsXdo
return getHibernateTemplate XB)D".\
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().findByNamedQuery(query, parameters); (bsx|8[
} b6D;98p
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publicList find(finalString query){ &."$kfA+
return getHibernateTemplate().find $DbnPZ2$
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(query); }Q\%tZC#T
} nBh+UT}
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publicList find(finalString query, finalObject F9K%f&0 a
)GD7rsC`<
parameter){ u,^CFws_
return getHibernateTemplate().find K d&/9<{>
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(query, parameter); sPH2KwEv
} H QqFrR
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public PaginationSupport findPageByCriteria ]}2)U
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(final DetachedCriteria detachedCriteria){ e;]tO-Nu
return findPageByCriteria TZn
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); c_J9CKqc
} iC"iR\Qu
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public PaginationSupport findPageByCriteria "Ep"$d
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(final DetachedCriteria detachedCriteria, finalint `m,4#P-kj
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startIndex){ -F 5BJk
return findPageByCriteria djd/QAfSC
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(detachedCriteria, PaginationSupport.PAGESIZE, BU`X_Z1)
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startIndex); F/5&:e?( )
} 6= iHw24
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public PaginationSupport findPageByCriteria x#1Fi$.
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(final DetachedCriteria detachedCriteria, finalint 56V|=MzX]
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pageSize, H$![]Ujq
finalint startIndex){ 6o't3Peh
return(PaginationSupport) n`Q@<op
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getHibernateTemplate().execute(new HibernateCallback(){ O1c%XwMn^
publicObject doInHibernate fG0 ?"x@>
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(Session session)throws HibernateException { rXx#<7`
Criteria criteria = c(Q@5@1y:
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detachedCriteria.getExecutableCriteria(session); 'uL4ezTtA
int totalCount = K_i|cYGV
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((Integer) criteria.setProjection(Projections.rowCount b8WtNVd
4Aj~mA
()).uniqueResult()).intValue(); l\<.*6r
criteria.setProjection L2H
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(null); 8>KUx]AN
List items = m:@y_:X0
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criteria.setFirstResult(startIndex).setMaxResults mjeJoMvN)H
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(pageSize).list(); =p5DT
PaginationSupport ps = DbGS]k<$
br I;}m
new PaginationSupport(items, totalCount, pageSize, n!)$e;l
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startIndex);
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return ps; ee {ToK
} Fh #QS'[
}, true); omE- c
} ! M^O\C)
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public List findAllByCriteria(final t2[/eM.G
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DetachedCriteria detachedCriteria){ =%<=Bn
return(List) getHibernateTemplate "i0>>@NR'
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().execute(new HibernateCallback(){ z; GQnAG@
publicObject doInHibernate VN`.*B|9[
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(Session session)throws HibernateException { )vW'g3u _
Criteria criteria = h;V4|jM
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detachedCriteria.getExecutableCriteria(session); "&6vFm r
return criteria.list(); OZ&/&?!XE
} 9nFL70
}, true); 9c@M(U@Yh
} LG[N\%<!H
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public int getCountByCriteria(final }e\"VhAl/
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DetachedCriteria detachedCriteria){ ZJDV'mC}
Integer count = (Integer) Q yqOtRk
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getHibernateTemplate().execute(new HibernateCallback(){ Ci`o;KVj
publicObject doInHibernate _dKMBcl)E
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(Session session)throws HibernateException { | 6{JINW
Criteria criteria = aC1z.?!U
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detachedCriteria.getExecutableCriteria(session); QuR}6C
return NBk0P*SI
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criteria.setProjection(Projections.rowCount w)7y{ya$
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()).uniqueResult(); S~ /2Bw!2
} NjIPHM$g
}, true); C^ZoYf8+"m
return count.intValue(); \c2x
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} 3Q,&D'];[
} SH)-(+72d
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用户在web层构造查询条件detachedCriteria,和可选的 +jhzE%
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 h*R@ d
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PaginationSupport的实例ps。 !q&Td
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ps.getItems()得到已分页好的结果集
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ps.getIndexes()得到分页索引的数组 +,,(8=5g
ps.getTotalCount()得到总结果数 ao)';[%9s
ps.getStartIndex()当前分页索引 LG8h@HY&L
ps.getNextIndex()下一页索引 rR6}
ps.getPreviousIndex()上一页索引 GL?b!4xx
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ,ayEZ#4.m
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 KO" /
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一下代码重构了。 wp@_4Iq1$
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我把原本我的做法也提供出来供大家讨论吧: ?9t4>xKn
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首先,为了实现分页查询,我封装了一个Page类: P!]uJ8bi
java代码: Gko"iO#
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/*Created on 2005-4-14*/ l7g'z'G
package org.flyware.util.page; TVcA%]y{;
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/**
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* @author Joa |RL#BKC`
* wW\[#Ku
*/ R ` ViRJh
publicclass Page { bB?E(>N;
"r46Rfa
/** imply if the page has previous page */ >OaD7
privateboolean hasPrePage; `rVru= zoy
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/** imply if the page has next page */ Dy.i^`7\
privateboolean hasNextPage; ir<e^a
qt}M&=}8Q
/** the number of every page */ n725hY6}<l
privateint everyPage; ~1+6gG
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/** the total page number */ %_W4\
privateint totalPage; k7iko{5D
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/** the number of current page */ SO6)FiPy!n
privateint currentPage; }O*`I(
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/** the begin index of the records by the current [eD0L71[
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query */ _f0AV;S:vd
privateint beginIndex; o{y}c->
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/** The default constructor */ FL{?W (M
public Page(){ ^i%S}VK
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} 1_TuA(
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/** construct the page by everyPage j"nOxs
* @param everyPage JVuju$k
* */ o=YOn&@%
public Page(int everyPage){
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this.everyPage = everyPage; ."+lij=56
} 0:v!'
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/** The whole constructor */ M<Wi:r:
public Page(boolean hasPrePage, boolean hasNextPage, #`u}#(
FPY k`D
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int everyPage, int totalPage, V8/d27\
int currentPage, int beginIndex){ !ekByD
this.hasPrePage = hasPrePage; /u$'=!<b;
this.hasNextPage = hasNextPage; Y$L`
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this.everyPage = everyPage; zhw*Bed<
this.totalPage = totalPage; R@K\
this.currentPage = currentPage; QH-CZ6M
this.beginIndex = beginIndex; E /H%q|q
} WhW}ZS'r
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/** Be|! S_Y P
* @return Gk~aTO
* Returns the beginIndex. `Xos]L'w
*/ /f[Ek5/-0
publicint getBeginIndex(){ XN<!.RCw
return beginIndex; iL;V5|(sb
} "0!h-bQN
"IU}>y>J
/** ?1ey$SSU]
* @param beginIndex ;$iT]S
* The beginIndex to set. ?V2P]|
*/ J,Ki2'=
publicvoid setBeginIndex(int beginIndex){ ]ltCJq
this.beginIndex = beginIndex; \s#~ %l
} o:#jvi84F
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/** wG)e8,#
* @return pl>b 6 |
* Returns the currentPage. oSrA4g
*/ zh2<!MH
publicint getCurrentPage(){ $}(Z]z}O ;
return currentPage; g}hUCx(
} }p?,J8=-
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/** W$jRS
* @param currentPage ug]2wftlQ
* The currentPage to set. H}r]j\
*/ K ar!
publicvoid setCurrentPage(int currentPage){ IER;d\_V<
this.currentPage = currentPage; &n| <NF
} O.FTToh<
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/** @2"uJ6o
* @return drAJ-ii
* Returns the everyPage. "S#$:92
*/ }$<v
publicint getEveryPage(){ $@6q5Iz!&
return everyPage; eM!Oc$C8[
} 0dwD ?GG2
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/** %S^ke`MhF
* @param everyPage $zOV*O2
* The everyPage to set. ]A[}:E 5}
*/ Srw`vql{(
publicvoid setEveryPage(int everyPage){ GdC=>\]
this.everyPage = everyPage; r2f%E:-0G
} kR1
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/** )PR`irw
* @return ,8DC9yM,
* Returns the hasNextPage. b:9"nALgC
*/ uLv
publicboolean getHasNextPage(){ MX*4d{ l
return hasNextPage; rk%pA-P2
} >Ch2Ep
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/** q !}~c
* @param hasNextPage M%jR`qVFg.
* The hasNextPage to set. lw8t#_P
*/ <>5n;-
publicvoid setHasNextPage(boolean hasNextPage){ iPCn-DoIS
this.hasNextPage = hasNextPage; 0{d)f1
} *B4OvHi)'
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/** \*5z0A9)5)
* @return a-#$T)mmfj
* Returns the hasPrePage. `E;xI v|
*/ +bso4 }rS
publicboolean getHasPrePage(){ c;KMox/
return hasPrePage; tw 3zw`o:
} 2ETv H~23
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/** I=Y_EjZD
* @param hasPrePage o=![+g
* The hasPrePage to set. ;fQIaE&H
*/ v!DU ewz
publicvoid setHasPrePage(boolean hasPrePage){ }] 1C=~lC
this.hasPrePage = hasPrePage; #$ka.Pj
} lt'N{LFvc
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/** `"V}Wq ?I
* @return Returns the totalPage. ,9KnC=_y
* b5~p:f-&4B
*/ E>|fbaN-%
publicint getTotalPage(){ 7#&Q-3\:
return totalPage; tJ7tZ~Ak
} wqjR-$c
$PlMyLu7jc
/** Vv`94aQTD
* @param totalPage [\ 0>@j}Z
* The totalPage to set. ^VnnYtCRz
*/ ES(qu]CjI
publicvoid setTotalPage(int totalPage){ 9%Vy,
this.totalPage = totalPage; mU[
} 8B "^}y\0
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} trA ^JY
wrJ"(:VZ
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 x*X{*?5@
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个PageUtil,负责对Page对象进行构造: 8F$]@0v`%
java代码: 0=9$k
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/*Created on 2005-4-14*/ hoiC
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package org.flyware.util.page; yr.sfPnJK
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import org.apache.commons.logging.Log; " w /Odd
import org.apache.commons.logging.LogFactory; s|[qq7
qjg Z
/** f"4w@X2F
* @author Joa v@fy*T\3
* ra@CouR^c{
*/ G~4G$YL*
publicclass PageUtil { +'VYqu/
wT,=C'
privatestaticfinal Log logger = LogFactory.getLog UQP>yuSx
d\c)cgh%
(PageUtil.class); <1QXZfQ"
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/** n7/&NiHxv/
* Use the origin page to create a new page \lwLVe
* @param page PH^Gjm
* @param totalRecords d*U<Ww^q
* @return &2ty++gC
*/
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publicstatic Page createPage(Page page, int nuA
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totalRecords){ \#N?
return createPage(page.getEveryPage(), 5e?<x>e
`9T5Dem|#
page.getCurrentPage(), totalRecords); xm=$D6O:
} {/,AMJ<:G]
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/** );n/G
* the basic page utils not including exception .2ZFJ.Z"
}EJ/H3<
handler NQvI=R-g
* @param everyPage |goK@<
* @param currentPage U9
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* @param totalRecords jmP;(j.|
* @return page )me`Ud
*/ YPCitGBl
publicstatic Page createPage(int everyPage, int B`jq"[w]-
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currentPage, int totalRecords){ )V_;]9<wt
everyPage = getEveryPage(everyPage); } .<(L
currentPage = getCurrentPage(currentPage); }WBHuVcZG
int beginIndex = getBeginIndex(everyPage, 2. {/ls
7;&,LH
currentPage); 4x#tUzb;
int totalPage = getTotalPage(everyPage, $2-_j)+
d9%P[(yM^
totalRecords); AD@ {7
boolean hasNextPage = hasNextPage(currentPage, g=,}j]tl
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totalPage); M* {5> !\
boolean hasPrePage = hasPrePage(currentPage); eg1F[~YL/
dep"$pys>
returnnew Page(hasPrePage, hasNextPage, h ^s8LE3
everyPage, totalPage, |k,-]c;6
currentPage, 1-&L-c.
[9#zEURS
beginIndex); #VVfHCy
} x($Djx
Xkg
privatestaticint getEveryPage(int everyPage){ >7S@3,C3ke
return everyPage == 0 ? 10 : everyPage; HPJHA ,
}
;Me*#/
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privatestaticint getCurrentPage(int currentPage){ (oG.A
return currentPage == 0 ? 1 : currentPage; _mwt{D2r}
} KC9e{
bMNr +N
privatestaticint getBeginIndex(int everyPage, int "Wr[DqFd
K>b4(^lf
currentPage){ rPqM&&+
return(currentPage - 1) * everyPage; \xv(&94U
} 3JkdP h
ecR)8^1 '
privatestaticint getTotalPage(int everyPage, int x{tlC}t
H\\FAOj
totalRecords){ g|7o1{
int totalPage = 0; \iP@|ay9
qMA-#
if(totalRecords % everyPage == 0) F*r)
totalPage = totalRecords / everyPage; Pd(_
else uoeZb=<
totalPage = totalRecords / everyPage + 1 ; mtn^+*
"k{so',7z
return totalPage; /]MelW
} 0K26\1
w`V6vYd@
privatestaticboolean hasPrePage(int currentPage){ Jww#zEK
return currentPage == 1 ? false : true; .kn2M&P>=
} |%mZ|,[
\=bKuP(it
privatestaticboolean hasNextPage(int currentPage, s.Ai_D
) ba~7A
int totalPage){ DL1nD5
return currentPage == totalPage || totalPage == g= Vu'p 3u
O=(F46 M
0 ? false : true; i/1$uQ
} t"q'"FX
k%i.B
gu[EYg
} "wTCO1
C&MqH.K
J:Qx5;b;
}X^MB
L-C^7[48=
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。 ce}A!v
10*Tk 8
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 o,dp{+({
X )tH23
做法如下: f!w/zC .
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >19s:+
e&d$kUJrq
的信息,和一个结果集List: 9n{Y6I
x:
java代码: h%ys::\zF
]Z8u0YtM)
nH6SA1$kW
/*Created on 2005-6-13*/ C1=&Vm>g+
package com.adt.bo; cOX )+53
`?(J(H
import java.util.List; xL"J?Gy
;Jg$C~3tf
import org.flyware.util.page.Page; EHm*~Sd
@qp6Y_,E[
/** Sl,DZ!
* @author Joa xsj,l@Ey
*/ WF~BCP$OR
publicclass Result { aO&{.DO2
`D~oY=
private Page page; t8EI"|
iIX%%r+
private List content; SefhOh^,V
K}re{y
/** q| 1%G Nb
* The default constructor yV:8>9wE8
*/ "gM!/<~
public Result(){ Yu_*P-Ja6
super(); Y:TfD{Xgc
} !<:Cd(bM
e72Fz#<q
/** X1.-C@o
* The constructor using fields M> WWP3
* P ljPhAce
* @param page +\Jo^\
* @param content 4uOR=+/l
*/ q<q IT
public Result(Page page, List content){ !\R5/-_UU
this.page = page; ojnO69v
this.content = content; auK9wQ%\
} { im?tZ,
p-.kBF
/**
QvZ"{
* @return Returns the content. 7wx=#
*/ piM4grg
\
publicList getContent(){ #Pg`0xiV
return content; Eu(QeST\
} h6D4CT
tJ;qZyy(
/** 90W=v*
* @return Returns the page. \KhcNr?ja=
*/ yR>P
public Page getPage(){ =fRS UtX
return page; GbQi3%
} N E9,kWI
0o>C,
`
/** zJw5+
+
* @param content 88_ef7w
* The content to set. .?6p~
*/ ?m *e$!M0
public void setContent(List content){ Uyb0iQ-,s
this.content = content; -z`%x@F<&L
} S~aWun
3XQa%|N(
/** >(a35 b$
* @param page p}!i_P
* The page to set. zz
U,0
L
*/ s;TB(M~i[
publicvoid setPage(Page page){ ,K,st+s|
this.page = page; 4aOz=/x2
} D{B?2}X
} b69nj
\o[][R#D
o^2MfFS
j<(E%KN3
9k;,WU(K<
2. 编写业务逻辑接口,并实现它(UserManager, &q<k0_5Q
<CuUwv
'A
UserManagerImpl) ly`
A,dh
java代码: 4O-LLH
i,;JI>U
y5eEEG6
/*Created on 2005-7-15*/ htbE
Q NW
package com.adt.service; UPGUJ>2Z
L/ibnGhq]
import net.sf.hibernate.HibernateException; ExtC\(X;
9~W]D!m,
import org.flyware.util.page.Page; n{TWdC
vgy.fP"@
import com.adt.bo.Result; L-`V^{R]
aC}\`.Kb
/** gNW+Dq|X%
* @author Joa cS%dTrfo
*/ X?t;uZI^
publicinterface UserManager { Zm0VaOT $I
W2X`%Tx0
public Result listUser(Page page)throws }
TUr96
&7\}Sqp
HibernateException; \Vx^u}3O
E&cC2(w
} 1?&|V1vc
{*+J`H_G2a
-*mbalU,J
m"~ddqSMT
7T[$BrO\
java代码: d\>XfS
X:s~w#>R
Ua
\f]y
/*Created on 2005-7-15*/ zp8x/,gwF
package com.adt.service.impl; iHNQxLkk{:
0M;g&&mF
import java.util.List; ZS+m}.,whQ
t[2b~peNI
import net.sf.hibernate.HibernateException; CjPdN#*l
^|Z'}p|&
import org.flyware.util.page.Page; _<f%==
I'
import org.flyware.util.page.PageUtil; _0$>LWO~
|v7Je?yh
import com.adt.bo.Result; 2?7ID~\
import com.adt.dao.UserDAO; Zo2+{a
import com.adt.exception.ObjectNotFoundException; >g !Z|ju
import com.adt.service.UserManager; {v'eP[
m^XO77"
/** aR3jeB,=x
* @author Joa k5K5OpY
*/ qZ!kVrmg&
publicclass UserManagerImpl implements UserManager { (.=Y_g.
.b_ppieNY
private UserDAO userDAO; !B Pm{_C
&*/= `=:C8
/** ngZq]8=o
* @param userDAO The userDAO to set. Mw,]Pt6~i
*/ e~
OrZhJ=_
publicvoid setUserDAO(UserDAO userDAO){ %' WC7s
this.userDAO = userDAO; ?<.a>"!
} HYO/]\al
3M?O(oO
/* (non-Javadoc) >dK0&+A
* @see com.adt.service.UserManager#listUser Z{vc6oj
!+$QN4{9
(org.flyware.util.page.Page) wg[
+NWJ
*/ GmNCw5F
public Result listUser(Page page)throws F^{31iU~CX
>k\p%{P
HibernateException, ObjectNotFoundException { y(<{e~
int totalRecords = userDAO.getUserCount(); #Ev}Gf+5Q
if(totalRecords == 0) Kh4rl)L*+%
throw new ObjectNotFoundException ,k_ b-/
+a,#BSt
("userNotExist"); Q[3hOFCX
page = PageUtil.createPage(page, totalRecords); JtSwbdN
List users = userDAO.getUserByPage(page); R%r25_8
returnnew Result(page, users); 4P?`<K'
} pvl];w
6@lZVM)E
} +cXi|Zf
LsI@_,XW<
T]Q4=xsv
XBX`L"0
whe%o
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 bHm/Z Zx
&Oz
询,接下来编写UserDAO的代码: -wH0g^Ed
3. UserDAO 和 UserDAOImpl: bbS,pid1
java代码: :Nf(:D8
\nyqW4nTm
?/T=Gk
/*Created on 2005-7-15*/ \c{sG\ >
package com.adt.dao; d]K8*a%[-
dm"x?[2:
import java.util.List; fup?Mg-
s\~j,$Mm2
import org.flyware.util.page.Page; 9a@S^B>
5`&@3
m9/
import net.sf.hibernate.HibernateException; J"h2"$v,
"x]7et,
/** ODKh/u_
* @author Joa 0iC5,
*/ 0FL'8!e<
publicinterface UserDAO extends BaseDAO { <#"_Qgdix
*1-0s*T
publicList getUserByName(String name)throws p;7wH\c
/g%RIzgW
HibernateException; LZG(T$dI
3rZPVR$))
publicint getUserCount()throws HibernateException; +-TEB
gkTwGI+w
publicList getUserByPage(Page page)throws
!Q_Kil.9
|;aZi?Ek[
HibernateException; jC:D>
p|qLr9\A
} ~#so4<A`3
QTF1~A\
=],c$)
#68$'Rl"o1
iM9k!u FE
java代码: Ap"%%D^{:
|FaK=e
"5$p=|
/*Created on 2005-7-15*/ MUtM^uY
package com.adt.dao.impl; D8B\F5..c#
WSU/Z[\`H
import java.util.List; MVQ6I/EA4
/18fpH|
import org.flyware.util.page.Page; e50xcf1u
S}Z@g
import net.sf.hibernate.HibernateException; g hkV^ [
import net.sf.hibernate.Query; Q>\DM'{:4
6r%i=z
import com.adt.dao.UserDAO; JX>`N5s
@kT@IQkri
/** |_s,]:
* @author Joa
BlT)hG(M>
*/ X$t!g`
public class UserDAOImpl extends BaseDAOHibernateImpl +g1+,?cU
hCX/k<}I
implements UserDAO { KG(l=? N
,N_V(Cx5pt
/* (non-Javadoc) qM
Qu!%o
* @see com.adt.dao.UserDAO#getUserByName S;#7B?j
x=\W TC
(java.lang.String) NVom6K
*/ D#Mz#\4o
publicList getUserByName(String name)throws \SgBI/L^
wYS r.T8Q
HibernateException { |hDN$By
String querySentence = "FROM user in class
l]
x
FvKjO)
com.adt.po.User WHERE user.name=:name"; WkpHe
Query query = getSession().createQuery hVZS6gU,x
CNWA!1n^Hy
(querySentence); .M[t5I'\
query.setParameter("name", name); x],XiSyp
return query.list(); = 'e_9b\K
} 3:OqD~,zy
uXA}" f2
/* (non-Javadoc) 'w/S6j
* @see com.adt.dao.UserDAO#getUserCount() 7#N= GN
*/ XVKRT7U
publicint getUserCount()throws HibernateException { j(pe6
int count = 0; (II#9n)
String querySentence = "SELECT count(*) FROM 79jnYjk
QPFv]^s(
user in class com.adt.po.User"; :8v? 6Q
Query query = getSession().createQuery @y
eAM7
bXM&VW?OP
(querySentence); %w!x \U V
count = ((Integer)query.iterate().next m.5@qmQ
G]Im.x3O-
()).intValue(); tC/+
return count; -2C^M> HZ
} zf\$T,t)
0@
vzQ$
/* (non-Javadoc) VEL!-e^X&
* @see com.adt.dao.UserDAO#getUserByPage yZmeke)_
y"_rDj`
(org.flyware.util.page.Page) p~-)6)We?
*/ $P #KL//
publicList getUserByPage(Page page)throws M@pF[J/
m_;XhO
HibernateException { W=n
Hi\jLV
String querySentence = "FROM user in class bc& 5*?
@JJ{\?>
com.adt.po.User"; Hm~.u.)\.
Query query = getSession().createQuery XWB#7;,R
ki?V
eFp
(querySentence); 1l.HQ IS
query.setFirstResult(page.getBeginIndex()) MTbCL53!-
.setMaxResults(page.getEveryPage()); 6>b#nFVJ
return query.list(); b:
I0Zv6
} gU@R
Z3X9-_g
} _( QW2m?K
T!1XL7
ciCQe]fS
LO%OH
u}]
a{.-qp
至此,一个完整的分页程序完成。前台的只需要调用 4`?WdCW8
AbX#wpp!
userManager.listUser(page)即可得到一个Page对象和结果集对象 uPb. uG
v\=k[oOu
的综合体,而传入的参数page对象则可以由前台传入,如果用 8;3I:z&muQ
1<0Z@D~F
webwork,甚至可以直接在配置文件中指定。 C&.Q|S2_
kr44@!s+'
下面给出一个webwork调用示例: 1[e%E#h
java代码: tR?)C=4,
7aHP;X~0
tYhNr
/*Created on 2005-6-17*/ cfc=a
package com.adt.action.user; }~v0o#
I
LiEDTXRz
import java.util.List; T^2o'_:
UrdSo"%
import org.apache.commons.logging.Log; J
c:j7}OOV
import org.apache.commons.logging.LogFactory; 22E I`}"J
import org.flyware.util.page.Page; c:-n0m'i
E/C3t2@-
import com.adt.bo.Result; j__l'?s
import com.adt.service.UserService; W: 3fLXk+
import com.opensymphony.xwork.Action; KP
gzB^>
6D4 j];~X
/** Lv-M.
* @author Joa yDi'@Z9R?
*/ PWS5s^WM
publicclass ListUser implementsAction{ T?{F7
v;Rm42k
privatestaticfinal Log logger = LogFactory.getLog X D\;|
F^cu!-L
(ListUser.class); ]q|U0(q9
+
$Lc'G+:
private UserService userService; Shu=oweJ
oox;8d4}y
private Page page; I:] Pd
,'@t.XP
privateList users; 2nI^fVR%\
^{64b
/* _Hv@bIL'
* (non-Javadoc) @.h;k4TD
* \WM"VT
* @see com.opensymphony.xwork.Action#execute() |p*s:*TJp
*/ Y-]Ne"+vf
publicString execute()throwsException{ %WFZ&>en&
Result result = userService.listUser(page); >8gb/?z
page = result.getPage(); G@,XUP
users = result.getContent(); f}Uf*Bp
return SUCCESS; f<Yg_ TG
} d-B,)$zE
H) q_9<;
/** 3:3>k8
* @return Returns the page. ;<BMgO}N
*/ t0)XdIl8
public Page getPage(){ o3oTu
return page; R(#ZaFuo[
} p9~$}!ua
U;FJSy
/** Jmun^Q/h
* @return Returns the users. \mNN ) K@
*/ j2=|,AmC
publicList getUsers(){ B5!|L)7>{p
return users; fD2)/5j1
} RFLw)IWkL_
Z4D[nPm$
/** i:
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* @param page NoT%z$1n
* The page to set. !5>PZ{J
*/ Ypx"<CKP}
publicvoid setPage(Page page){ ;~( yv|f6
this.page = page; uS5ADh
} /2:s g1
v`r*Yok;`
/** {z |+.D
* @param users @8lT*O2j
* The users to set. 0G(|`xG1q
*/ ,7SqRY,+
publicvoid setUsers(List users){ af}JS2=$
this.users = users; NwNjB
w%v
} }hS$F
~SYW@o
/** Fq'Ds[wd5
* @param userService =s,}@iqNO4
* The userService to set. R#HX}[Hb
*/ )8_MkFQe
publicvoid setUserService(UserService userService){ JHg
y&/
this.userService = userService; UZJ#/x5F
} @oQ"FLF.
} b8|<O:]Hp
pg{cZ1/
EAK[2?CY
}gKJ~9Jg
05o<fa 2HE
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, cue aOtD
Fmzkbt~oe
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 VUZeC,FfO
T%w5%{dqJ
么只需要: !HKW_m^3J
java代码: q I*7ToBJ
]E#W[6'VtB
Dw<bLSaW&
<?xml version="1.0"?> :jFZz%
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork $ J!PSF8PL
ogJ *
1.0//EN" "http://www.opensymphony.com/xwork/xwork- .HPa\b\L>
L+8O
4K{
1.0.dtd"> I/go$@E"
>tm4Rg~y
<xwork> Av!xI
m|Sf'5fK
<package name="user" extends="webwork- %uvA3N>
,@\z{}~v
interceptors"> 1,+swFSN
A[uB)wWsn
<!-- The default interceptor stack name C]Q}HI#G
y:Aha#<
--> ~bz$] o-<
<default-interceptor-ref v1=N?8Hz1
"iUh.c=0F,
name="myDefaultWebStack"/> 0bteI*L
{+V ]@sz
<action name="listUser" +3Z+#nGtk
^0?ww&X
class="com.adt.action.user.ListUser"> G|TnvZ KX
<param *0'< DnGW
X XxH<E$p
name="page.everyPage">10</param> eo^C[#
.
<result Ok<,_yh
$GYy[8{:V
name="success">/user/user_list.jsp</result> h=^UMat-
</action> ~zVe?(W
()5X<=i
</package> uZ'(fnZ$
wLNkXC
</xwork> m[Mw2 F
yT[=!M
tJA"BP3f
[}l#cG6 k
H-mQ{K^
4gZ)9ya
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 fNBI!=
IkO[R1K
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 _%#Uh#7P$
a'r1or4
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Y^ y:N$3$\
r_kaS
als
4*HBCzr7[
~y"OyO i&
(LJ7xoJ^
我写的一个用于分页的类,用了泛型了,hoho 4p%^?L?
6C/Pu!Sx?
java代码: QL*RzFAD3
`?SC.KT
Q$sC%P(y
package com.intokr.util; K(HrwH`a{
N-q6_
import java.util.List; <p-@XzyE
q_9 8=fyE6
/** WD! " $
* 用于分页的类<br> D1@yW}
4
* 可以用于传递查询的结果也可以用于传送查询的参数<br> HTMg{_r(%
* o-JB,^TE
* @version 0.01 vP=H 2P
* @author cheng Z4E6J'B8
*/ +ej5C:El_}
public class Paginator<E> {
HLQ>
|,9
privateint count = 0; // 总记录数 p<?lF
privateint p = 1; // 页编号 ]9c{qm}y
privateint num = 20; // 每页的记录数 \v$zU
privateList<E> results = null; // 结果 u:tcL-;U
!6a;/ys
/** _dW#[TCF
* 结果总数 ivB,s5<
*/
V<?0(esgR
publicint getCount(){ J3e'?3w[
return count; ydj*Jy'
} rY8(`a
*ae)<l3v
publicvoid setCount(int count){ GG-b)64h`
this.count = count; Zg0nsNA
} d|)ARRW
?$uEN_1O\@
/** .mcohfR
* 本结果所在的页码,从1开始 +$#XV@@~
* ynZEJKo
* @return Returns the pageNo. c;!|=
*/ 9W_mSum
publicint getP(){ Ts3!mjn
return p; f9
:=6
} ^f-)gZ&
{v|ib112;
/** X.FoX
* if(p<=0) p=1 uI&0/
* !%DE(E*'(
* @param p BwGOn)KL
*/ -B!
a
O65^
publicvoid setP(int p){ r!w*y3
if(p <= 0) @F*z/E}e
p = 1; |T/s>OW
this.p = p; q/Ji}NGm
} Gpcordt/
jTZi<
Y:bB
/** FP7N^HVBG=
* 每页记录数量 ]YfG`0eK<
*/ aY;34SF
publicint getNum(){ z@?y(E
return num; g_k95k3V'
} 49O_A[(d
.j"heYF)
/** 6}0_o[23
* if(num<1) num=1 Vpzjh,r-j
*/ -*hPEgcV9
publicvoid setNum(int num){ Ey%[t
if(num < 1) wZbT*rU
num = 1; l0qHoM,1Y[
this.num = num; ~E_irzOFP
} Z=;=9<vA
$uUyp8F
/** 0(9gTxdB
* 获得总页数 H 8 66,]
*/ R/Sm
publicint getPageNum(){ CdcBE.%<
return(count - 1) / num + 1; w)1SZ}
} k6Vs#K7a
;~WoJlEK3
/** AW9%E/{
* 获得本页的开始编号,为 (p-1)*num+1 nw_|W)JVQ
*/ G&MO(r}B
publicint getStart(){ ,zH\P+*
return(p - 1) * num + 1; 30(e6T;
} p]Qe5@NT
-;RAW1]}Y$
/** 1DL+=-
* @return Returns the results. MrOtsX
*/ pCa~:q*85
publicList<E> getResults(){ jv1p'qs4
return results; 8{{^pW?x
} E%stFyr9`/
P9Eh,j0_
public void setResults(List<E> results){ zJ ;]z0O
this.results = results; d~QJ}a
} j.+,c#hFo
KVViTpZ
public String toString(){ ,'l.u?SKyd
StringBuilder buff = new StringBuilder v]KPA.W
$[J\sokpY
(); 5"q{b1
buff.append("{"); 2!{_x8,n
buff.append("count:").append(count); A,=
R`m
buff.append(",p:").append(p); V2tA!II-s
buff.append(",nump:").append(num); SL^%Zh/~
buff.append(",results:").append mt e3k=17
\S~<C[P
(results); AO5a
buff.append("}"); WFS6N.Ap
return buff.toString(); Y!|};
} x0TE+rf5
wc~ 9zh
} S%7bM~J@
6Hd^qouid
DAEWa
Kui