Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 sF$m?/Kt
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 -O5m@rwt<
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 R4/@dA0
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 (0+m&,
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分页支持类: riL!]'akV
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java代码: [xPE?OD
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package com.javaeye.common.util; J[l K
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import java.util.List; *"ShE=\p
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publicclass PaginationSupport { +[ zo2lBx
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publicfinalstaticint PAGESIZE = 30; w(D9'
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privateint pageSize = PAGESIZE; rx/6x(3
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privateList items; 9m6j?CFG}
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privateint totalCount; 3[0:,^a
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privateint[] indexes = newint[0]; (XJQ$n
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privateint startIndex = 0; ~}w 8UO
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public PaginationSupport(List items, int WQx;tX
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totalCount){ jH1~Ve+q9
setPageSize(PAGESIZE); :X
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setTotalCount(totalCount); Vd4osBu{fY
setItems(items); ;"Y6&YP<
setStartIndex(0); &UR/Txnu
} U:r2hqegd
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public PaginationSupport(List items, int w3>|mDA}I
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totalCount, int startIndex){ 4(82dmKO
setPageSize(PAGESIZE); }3 }=tN5
setTotalCount(totalCount); ([~`{,sv
setItems(items); c29Z1Zs2)
setStartIndex(startIndex); 1tdCzbEn+
} 27:x5g?
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public PaginationSupport(List items, int
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totalCount, int pageSize, int startIndex){ ^~l<N@
setPageSize(pageSize); (rn x56I$
setTotalCount(totalCount); lQ"i]};<D
setItems(items); L:-lqag!
setStartIndex(startIndex); Qs:r@"hE
} s 'xmv{|
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publicList getItems(){ `'WLGQG
return items; [<QWTMjR
} 'Aj>+H<B
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publicvoid setItems(List items){ wjOAgOC
this.items = items; S!_?# ^t
} ISew]R2
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publicint getPageSize(){ /&7Yi_]r
return pageSize; fx:KH:q3
} (N4(r<o;
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publicvoid setPageSize(int pageSize){ ->=++
this.pageSize = pageSize; M7,MxwZ0k
} >N-%
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publicint getTotalCount(){
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return totalCount;
}8 _9V|E
} 8[;oUVb5
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publicvoid setTotalCount(int totalCount){ o[hP&9>q
if(totalCount > 0){ 79H+~1Az
this.totalCount = totalCount; (14kR
int count = totalCount / B}+9U
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pageSize; nD\os[ 3
if(totalCount % pageSize > 0) [dlH
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count++; J|S^K kC
indexes = newint[count]; mcr#Ze
for(int i = 0; i < count; i++){ "%*lE0Tx
indexes = pageSize * *J5RueUG
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i; X388Gs;e
} twmJ
}else{ mX@*2I
this.totalCount = 0; y51D-vj
} [[h)4H{T
} 9X9zIh]JV
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publicint[] getIndexes(){ L]N2rMM
return indexes; 92VX5?Cyg
} +|)1_NK
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publicvoid setIndexes(int[] indexes){ 6xh#;+e}
this.indexes = indexes; L^1q/4${
} z.&%>%TPP
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publicint getStartIndex(){ 9Pk3}f)a
return startIndex; i03}f%JnuO
} %C0O?q
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publicvoid setStartIndex(int startIndex){ I A#*T`
if(totalCount <= 0) e uHu}
this.startIndex = 0; O>M*mTM
elseif(startIndex >= totalCount) R(N(@KC
this.startIndex = indexes % W',c u
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[indexes.length - 1]; %yM'
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elseif(startIndex < 0) N 3p 7 0
this.startIndex = 0; ."Ix#\|x
else{ g*?+~0"`Y
this.startIndex = indexes =GKYroNM
*jw$d8q2
[startIndex / pageSize]; $1zeY6O
} 'O2#1SWe
} XW_xNkpL5c
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publicint getNextIndex(){ 9$V_=Bo
int nextIndex = getStartIndex() + 9^#gVTGXv
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pageSize; 0k0c
if(nextIndex >= totalCount) " IkF/
return getStartIndex(); .L5*E(<K0
else G4%M$LJh
return nextIndex; m4SXH> o
} I5yd )72
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publicint getPreviousIndex(){ 0$ 9;pzr
int previousIndex = getStartIndex() - ZQ' z
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pageSize; ,9tbu!Pvq
if(previousIndex < 0) %_R|@cyD
return0; ^Xy$is3
else k.xv+^b9Q
return previousIndex; @*O{*2
} Q=L$7
maUHjI
5A-
} ?Ga2K
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抽象业务类 NQiecxvt=
java代码: C:GHP$/}
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/** `I vw`} L
* Created on 2005-7-12 ?I2k6%a
*/ h3]@M$Y[
package com.javaeye.common.business; Q@W|GOH3
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import java.io.Serializable; Z:lB:U'o
import java.util.List; xe gL!
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import org.hibernate.Criteria; [zTYiNa
import org.hibernate.HibernateException; RTgA[O4J
import org.hibernate.Session; Ns|V7|n]
import org.hibernate.criterion.DetachedCriteria; SXo[[ao
import org.hibernate.criterion.Projections; 3pTS@
import kV:FJx0xP
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org.springframework.orm.hibernate3.HibernateCallback; 5
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import 3Da,]w<
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org.springframework.orm.hibernate3.support.HibernateDaoS @Tfwh/UN
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upport; :
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import com.javaeye.common.util.PaginationSupport; o(d_uJOB
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public abstract class AbstractManager extends +)JNFy-
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HibernateDaoSupport { ]o[X+;Tj|
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privateboolean cacheQueries = false; Q3Z%a|3W
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privateString queryCacheRegion; )`s;~_ZZ
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publicvoid setCacheQueries(boolean Cwsoz
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cacheQueries){ =|gJb|?w
this.cacheQueries = cacheQueries; s
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} x7KcO0F{
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publicvoid setQueryCacheRegion(String qb-2QPEB
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queryCacheRegion){ t(j_eq}J
this.queryCacheRegion = ,a9D~i 9R
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queryCacheRegion; B%eDBu
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} ^Cc8F3os=
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publicvoid save(finalObject entity){ e+F}9HR7
getHibernateTemplate().save(entity); j(Fa=pi
} /zl3&~4
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publicvoid persist(finalObject entity){ Y/^[qD
getHibernateTemplate().save(entity); ~tg1N^]kV
} rw5#e.~V
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publicvoid update(finalObject entity){ %$ir a\
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getHibernateTemplate().update(entity); rq<`(V'2
} /63W\
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publicvoid delete(finalObject entity){ ^sT+5M^
getHibernateTemplate().delete(entity); ;w+:8<mM}a
} W>}Qer4
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publicObject load(finalClass entity, y$j1?7
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finalSerializable id){ BcZEa^^~os
return getHibernateTemplate().load 42Aje
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(entity, id); d s|8lz,
} ?jNF6z*M6
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publicObject get(finalClass entity, IOsXPf9@
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finalSerializable id){ 670J{b
return getHibernateTemplate().get pAJ=f}",]E
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(entity, id); Z7/vrME6
} m\*&2Na
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publicList findAll(finalClass entity){ o{{:|%m3Q
return getHibernateTemplate().find("from 1-6gB@cvQ
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" + entity.getName()); Xzx[C_G
} Exep+x-
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publicList findByNamedQuery(finalString 6C:x6'5[
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namedQuery){ JdaFY+f:
return getHibernateTemplate Yw~;g:=
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().findByNamedQuery(namedQuery); y\F`B0#$
} nmD1C_&
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publicList findByNamedQuery(finalString query, 'v'`
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finalObject parameter){ y!7B,
return getHibernateTemplate ?-pxte8
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().findByNamedQuery(query, parameter); U/.w;DI
} !: m`9o8
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publicList findByNamedQuery(finalString query, " 2ZI oa!^
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finalObject[] parameters){ Q<RT12|`
return getHibernateTemplate 8s QQK.N(
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().findByNamedQuery(query, parameters); "[awmZ:wo
} 'fS?xDs-v
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publicList find(finalString query){ v\fzO#vj
return getHibernateTemplate().find gXq!a|eH
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(query); "%:7j!#X|I
} E=;BI">.
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publicList find(finalString query, finalObject Z -pyFK\
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parameter){ h^%GE;N
return getHibernateTemplate().find CHPL>'NJzc
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(query, parameter); AU0$A403
} Q8 -3RgAw
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public PaginationSupport findPageByCriteria P-[fHCg~
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(final DetachedCriteria detachedCriteria){ jZa25Z00
return findPageByCriteria >oe4mW
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); D35m5+=I
} M]J[6EW
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public PaginationSupport findPageByCriteria l!\1,J:}Z
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(final DetachedCriteria detachedCriteria, finalint uPFRh~ (b
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startIndex){ _mw13jcN]
return findPageByCriteria 53bM+
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(detachedCriteria, PaginationSupport.PAGESIZE, Lqg]Fd
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startIndex); ah 4kA LO
} )qbI{^_g
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public PaginationSupport findPageByCriteria Mg#`t$u
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(final DetachedCriteria detachedCriteria, finalint Dz,uS nnm
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pageSize, D=2~37CzQ1
finalint startIndex){ <H<!ht%q3
return(PaginationSupport) \.5F](:
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getHibernateTemplate().execute(new HibernateCallback(){ Dp^"J85}
publicObject doInHibernate &8Zeq3~
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(Session session)throws HibernateException { 1JIG+ZN md
Criteria criteria = }|AX_=a
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detachedCriteria.getExecutableCriteria(session); aZP2R"
int totalCount = z|uOJ0uK
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((Integer) criteria.setProjection(Projections.rowCount 7kdeYr~<1
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()).uniqueResult()).intValue(); w(/7Jt$
criteria.setProjection sD{j@WEZ
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(null); bk.*k~_
List items = w_\nB}_
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criteria.setFirstResult(startIndex).setMaxResults E\ tL
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(pageSize).list(); [9LxhPi
PaginationSupport ps = 6Ux[,]GK
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new PaginationSupport(items, totalCount, pageSize, ?qy*s3j'M
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startIndex); 3] N q@t
return ps; wXz\NGW
} )GK+
}, true); lBS"3s384
} g#w`J\iz
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public List findAllByCriteria(final tp@*=*^I
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DetachedCriteria detachedCriteria){ H*GlWgfG
return(List) getHibernateTemplate : g5(HH
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().execute(new HibernateCallback(){ uN8/Q2
publicObject doInHibernate { E^U6@
oI*d/*
(Session session)throws HibernateException { *u}'}jC1X
Criteria criteria = 3\1#eK'TK.
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detachedCriteria.getExecutableCriteria(session); 2R\+}
return criteria.list(); 7"#f!.E
} lVP |W:~K
}, true); |88CBiu}
} uj)yk*
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public int getCountByCriteria(final 55^tfu
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DetachedCriteria detachedCriteria){ GtC7^Z&E
Integer count = (Integer) r5[4h'f
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getHibernateTemplate().execute(new HibernateCallback(){ +^Fp&K+^
publicObject doInHibernate c+~LpSQ
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(Session session)throws HibernateException { #,TELzUVE
Criteria criteria = -;vT<G3
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detachedCriteria.getExecutableCriteria(session); Yc|uD-y
return 7_KXD#
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criteria.setProjection(Projections.rowCount (#If1[L
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()).uniqueResult(); 5?w.rcN[j
} ;I+H>$%jZ
}, true); vTHq)C.7G
return count.intValue(); "-P/jk
} f}2;N
} Je 31".
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用户在web层构造查询条件detachedCriteria,和可选的 *!w25t
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 yyjw?#\8
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PaginationSupport的实例ps。 *,&S' ,S-
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ps.getItems()得到已分页好的结果集 57<Di!rt
ps.getIndexes()得到分页索引的数组 x}|+sS,g
ps.getTotalCount()得到总结果数 I>aGp|4
ps.getStartIndex()当前分页索引 6A?8tm/0
ps.getNextIndex()下一页索引 IT18v[-G
ps.getPreviousIndex()上一页索引 hl<y4y&|
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 xp^ 7#`MJ?
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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 f3vF"O
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一下代码重构了。 ^KbL
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我把原本我的做法也提供出来供大家讨论吧: $''UlWK
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首先,为了实现分页查询,我封装了一个Page类: _C$X04bU3V
java代码: G,|KL" H6
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/*Created on 2005-4-14*/ #q;z8 @
package org.flyware.util.page; |z*>ixK
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/** (hN?:q?'
* @author Joa #kci=2q_
* Ha218Hy0W
*/ MMd.0JuaO
publicclass Page { `XgFga)
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/** imply if the page has previous page */ P0 b4Hq3
privateboolean hasPrePage; o0mJy'
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/** imply if the page has next page */ R5kH0{zM
privateboolean hasNextPage; 2M&$Wuu.q
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/** the number of every page */ *HeVACxo
privateint everyPage; S3y246|4
]2$x|#Gg}
/** the total page number */ >
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privateint totalPage; #c:kCZt#
E-SG8U;
/** the number of current page */ `tVy_/3(9
privateint currentPage; b 4OnZ;FI
^{[[Z.&R?
/** the begin index of the records by the current ,hvc``j
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query */ f3#X0.':
privateint beginIndex; hZU1O
bo>E"<
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/** The default constructor */ 8UM0vNk
public Page(){ nNQ-"t
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} ) EXJ
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/** construct the page by everyPage vQHpf>o
* @param everyPage {SdO9Yy?@7
* */ b# ='^W3
public Page(int everyPage){ VB"(9O]
this.everyPage = everyPage; 5v|EAjB6o
} =
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/** The whole constructor */ gDC2
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public Page(boolean hasPrePage, boolean hasNextPage, [.&[<!,.
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int everyPage, int totalPage, $^h?:L:1n
int currentPage, int beginIndex){ B}\BeFt'
this.hasPrePage = hasPrePage; -N# #w=
this.hasNextPage = hasNextPage; J\A8qh8
this.everyPage = everyPage; /b%Q[
Ck_
this.totalPage = totalPage; A ~&+F>Z
this.currentPage = currentPage; X"<|Z]w
this.beginIndex = beginIndex; @GeHWv
} :1_mfX
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/** 2Y+:,ud\
* @return ri=+(NKo-
* Returns the beginIndex. doLNz4W
*/ wW5Yw
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publicint getBeginIndex(){ i/$SN-5}1
return beginIndex; ,YB1 y)x
} |^Kjz{
5[R?iSGL1
/** l$M +.GB<
* @param beginIndex gtYRV*^q
* The beginIndex to set. "8/dD]=f^a
*/ m~>@BCn;
publicvoid setBeginIndex(int beginIndex){ U^ ?=
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this.beginIndex = beginIndex; J?D\$u:
} 1;&T^Gdj
tX?J@+
/** |GuEGmR
* @return (/?R9T[V&^
* Returns the currentPage. S#2[%o
*/ 2w4MJ,Uw
publicint getCurrentPage(){ Dbz]{_Y;
return currentPage; 0roCP=;
} QO,+ps<
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/** !^v\^Fc
* @param currentPage WQKj]:qk0
* The currentPage to set. a.,_4;'UE1
*/ +)gB9DoK
publicvoid setCurrentPage(int currentPage){ [ {cC
this.currentPage = currentPage; HJ@5B"
} m
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/** I%xn,u
* @return Xw^X&Pp
* Returns the everyPage. &t_h'JX&
*/ c#pj :f*H
publicint getEveryPage(){ (.Xr#;\(
return everyPage; t)r1"oA
} D^$OCj\
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/** ? OsS`)T
* @param everyPage y x;h
* The everyPage to set. X4Xf2aXI
*/ %h/! Y<%
publicvoid setEveryPage(int everyPage){ _9kIRmT{
this.everyPage = everyPage; H.~bD[gA
} 3_zSp.E\l
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/** n(R_#,Hs
* @return sFElD
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* Returns the hasNextPage. )eR$:uO
*/ x)R0F\_
publicboolean getHasNextPage(){ ?v.Gn9Z&
return hasNextPage; woau'7}XOu
}
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/** 'vlrc[|/
* @param hasNextPage q[c Etp28h
* The hasNextPage to set. N^J*!]|
*/ 9h&yuS'Yj
publicvoid setHasNextPage(boolean hasNextPage){ NvHN -^2
this.hasNextPage = hasNextPage; X9~p4ys9{
} {^m5#f 0"
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/** )U5u" ]9~
* @return v{koKQ'Y()
* Returns the hasPrePage. CZ tiWZ
*/ TzrW
publicboolean getHasPrePage(){ &+- e
return hasPrePage; v#U pw\!
} nh;y:Bi
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/** =v0~[E4
* @param hasPrePage xb`CdtG2.
* The hasPrePage to set. S@A<6
*/ or.\)(m#(
publicvoid setHasPrePage(boolean hasPrePage){ 5"gL.Ez
this.hasPrePage = hasPrePage; rzT{-DZB[4
} kM`7EPk
? s4oDi|:
/** X6kaL3L}
* @return Returns the totalPage. @p]UvqtB@
* \Tkp
*/ PbEQkjE
publicint getTotalPage(){ bA*"ei+!
return totalPage; JqEb;NiP)5
} :8]6#c6`74
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/** sam[s4@eQ
* @param totalPage Hirr=a3
* The totalPage to set. wY`#$)O0*
*/ ZIW7_Y>_
publicvoid setTotalPage(int totalPage){ K~@`o-Z[
this.totalPage = totalPage; O6]u!NqG
} ]_#SAhOR)
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} Zs73
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 {u4i*udG`)
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个PageUtil,负责对Page对象进行构造: Tk](eQsy.v
java代码: PUKVn+h
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/*Created on 2005-4-14*/ xVTo4-[p
package org.flyware.util.page; 2Fq=jOA)z$
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import org.apache.commons.logging.Log;
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import org.apache.commons.logging.LogFactory; ay-9c2E
' &N20w
/** cNeiD@t3V&
* @author Joa KBj@V6Q
* W0?JVtq0Z
*/ |*1xrM:v~
publicclass PageUtil { r\RFDj
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privatestaticfinal Log logger = LogFactory.getLog Q@Dkl
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(PageUtil.class); WKOI\
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/** RNe9h lr
* Use the origin page to create a new page Gym#b{#":
* @param page ZQ|gt*
* @param totalRecords `#p< rfe
* @return z L8J`W
*/ h[y*CzG
publicstatic Page createPage(Page page, int e# <4/FR
)w3
,
totalRecords){ D}Au6
return createPage(page.getEveryPage(), QH:>jmC{1h
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page.getCurrentPage(), totalRecords); J@gm@ jLc
} pJocI_v9
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/** T+(M8qb
* the basic page utils not including exception +K&?)?/=
*?p
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handler $r):d
* @param everyPage r;'i<t{P
* @param currentPage 6"%@L{UQ
* @param totalRecords Z,SY
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* @return page (H2ylMpQt
*/ GI?PGAT
publicstatic Page createPage(int everyPage, int EoKo
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currentPage, int totalRecords){ hd8B0eD'
everyPage = getEveryPage(everyPage); y,V6h*x2
currentPage = getCurrentPage(currentPage); -EVs@:3]j
int beginIndex = getBeginIndex(everyPage, VZTmzIk.Y
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currentPage); l[Tt[n
int totalPage = getTotalPage(everyPage, @wMQC\Z
@Jm.HST#S8
totalRecords); %fBP:5%K
boolean hasNextPage = hasNextPage(currentPage, 4?v$<=#21*
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totalPage); 3Qk/ Ll
boolean hasPrePage = hasPrePage(currentPage); nPcxknl(pd
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returnnew Page(hasPrePage, hasNextPage, n
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everyPage, totalPage, {N"*olx
currentPage, <5M_EJp
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beginIndex); }'v{dK
} %uj[ `
.(JE-upJ"
privatestaticint getEveryPage(int everyPage){ hRa\1Jt>a
return everyPage == 0 ? 10 : everyPage; *^uGvJXF
} p1kl LX
3Fgz)*Gu]
privatestaticint getCurrentPage(int currentPage){ )U]:9)
return currentPage == 0 ? 1 : currentPage; qg|Ox*_od"
} +;YE)~R?
vUqe.?5
privatestaticint getBeginIndex(int everyPage, int 4Q@\h=r
b'&LBT7
currentPage){ nT#37v
return(currentPage - 1) * everyPage; &yB%QX{3
} =,O/,2)
)dqR<)
privatestaticint getTotalPage(int everyPage, int 7:z>+AM[r
(x}A_i
totalRecords){ .l7j8}
int totalPage = 0; d3og?{i<}&
Gl.?U;4Z
if(totalRecords % everyPage == 0) ]9#CVv[rq
totalPage = totalRecords / everyPage; uW )
\,
else v: giZxR
totalPage = totalRecords / everyPage + 1 ; !;TR2Zcn
kp'b>&9r
return totalPage; J9NsHr:A[
} 'J2ewW5
o1Ne+Jt
privatestaticboolean hasPrePage(int currentPage){ ,tau9>!
return currentPage == 1 ? false : true; ix:2Z-
} 33*^($bE&
XMomFW_@
privatestaticboolean hasNextPage(int currentPage, KuIkul9^%
93 [rL+l.Y
int totalPage){ h>~jQ&\M
return currentPage == totalPage || totalPage == Fs?( UM
nT_*EC<.
0 ? false : true; F
~*zC`>Y
} s;anP0-O
O5ucI$s
u$ap H{
} %B[YtWqm`/
Tc9&mKVE%(
,?Ok[G!cm
TFNUv<>X
j[_t6Z
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 )uANmThOz
_L8Mpx*E
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 C(f$!~M4b
_c[|@D
做法如下: 3xRM
1GgO
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 n/xXQ7y
3Wjq >\
的信息,和一个结果集List: km9Gwg/zT
java代码: 5BrU'NF
lq~GcM
B.V?s,U
/*Created on 2005-6-13*/ 4 U3C~J
package com.adt.bo; MKV=m8G=
2r
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import java.util.List; $Vo/CZW7
8FAT(f//.
import org.flyware.util.page.Page; $$k7_rs
r5D jCV"
/**
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* @author Joa Cw6>^
*/ mYntU^4f
publicclass Result { iU.!oeR?
.UNF~}^H
private Page page; 1R5Yn(
s.|!Ti!]
private List content; )C'G2RV
X7t5b7
/** F~tm`n8Z
* The default constructor @~JB\j9
*/ P]|J?$1K
public Result(){ y2oB]^z&n
super(); 1[26w_B3
} >`<Ued
Mr$# e
/** aeEw#
* The constructor using fields OG0r4^6Ly
* );0<Odw%.
* @param page d\v$%0
* @param content b{Z^)u2X
*/ ev~dsk6k
public Result(Page page, List content){
m"96:v
this.page = page; $Sp*)A]E`
this.content = content; I8%d;G~
} !Sh^LYqn
h`z2!F4
/** kqj;l\N
* @return Returns the content. <8}KEe4
*/ k)?,xY\AV
publicList getContent(){ <9Lv4`]GU5
return content; bRx2
c
} ?| D$#{^
}wvwZ`5t
/** hu bfK~
* @return Returns the page. b=6MFPbg
*/ SZCF3m&pz
public Page getPage(){ LEYWH%y
return page; %1Vu=zCAW
}
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_<Hb(z
/** ( rA\_FOJ
* @param content ^L>MZA
?
* The content to set. yw;ghP;
*/ UN
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public void setContent(List content){ xI=}z
this.content = content; l=oN X"l=
} ZA*b9W
{DKXn`V
/** <C7M";54-
* @param page !yoSMI-
* The page to set. )e4WAlg8c
*/ 7Vz[ji
publicvoid setPage(Page page){ bBkm]
>
this.page = page; u Y?/B~
} .8u$z`j
} d$2@,
[VY8?y
A)b)ff ,
tIz<+T_
vjexx_fq
2. 编写业务逻辑接口,并实现它(UserManager, dzjB UD
.b=M5JsyV
UserManagerImpl) 2ApDpH`fiJ
java代码: YQN]x}:E+4
l 'AK
(z8]FT
/*Created on 2005-7-15*/ @-)<|orU4
package com.adt.service; P<j4\zJ
W0+gfg
import net.sf.hibernate.HibernateException; #rn4$
fe&
t-
import org.flyware.util.page.Page; .ujs`9d_-
uM6CG0
import com.adt.bo.Result; @A~B
,
yj}bY?4I
/** ^4xlZouCb
* @author Joa @+0@BO12
*/ l _kg3e4
publicinterface UserManager { T..N*6<X
&A ;3; R
public Result listUser(Page page)throws ..P=D <'f
E%wV
HibernateException; B$} wF<`k7
`l[6rf_.
}
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h/0<:eZ*
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D-TNFYYy2
java代码: Nt`F0
9S
nhVK?
Ct =E;v7}
/*Created on 2005-7-15*/ *([0"
package com.adt.service.impl; ^F0k2pB
L337/8fh
import java.util.List; %:'1_@Ot2
hQg,#r(JE4
import net.sf.hibernate.HibernateException; |g7nh[
[3{:H"t
import org.flyware.util.page.Page; g[=\KrTSg
import org.flyware.util.page.PageUtil; mC{!8WC@k
3oppV_^JdT
import com.adt.bo.Result; 8
7|8eU2:k
import com.adt.dao.UserDAO; ?{@!!te@3v
import com.adt.exception.ObjectNotFoundException; 2g ?Jb5)
import com.adt.service.UserManager; KV^:sxU
uJ|5Ve
/** ~n8Oyr
* @author Joa N8DiEB3~
*/ wRV`v$*6
publicclass UserManagerImpl implements UserManager { ;*>QG6Fh
((RpT0rP\
private UserDAO userDAO; D*d 3w
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/** OVQxZ~uQ
* @param userDAO The userDAO to set. ySr091Q
*/ X_0{*!v8
publicvoid setUserDAO(UserDAO userDAO){ n7`.<*:
this.userDAO = userDAO; 5fvUv"m
} :r
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DMK"Q#Vw
/* (non-Javadoc) |04}zU%N
* @see com.adt.service.UserManager#listUser j-I6QUd
[kp7LA"`
(org.flyware.util.page.Page) -Iruua7b
*/ 1v[#::Bs
public Result listUser(Page page)throws 9|G=KN)P:
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HibernateException, ObjectNotFoundException { 654jS!
int totalRecords = userDAO.getUserCount(); QAOk
if(totalRecords == 0) P5
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throw new ObjectNotFoundException P60]ps!M
Be14$7r
("userNotExist"); Ro3I/NI>
page = PageUtil.createPage(page, totalRecords); ?^G$;X7B
List users = userDAO.getUserByPage(page); P :7l#/x_
returnnew Result(page, users); e u=f-HW]
} -%/,j)VKD
V)?x*R*T)
} !g8.8(/t)
PE;0
jgsiI
D)/XP
EbwZZSds1
d=+Lv<
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 "` ?Wu
{L2Gb(YLW
询,接下来编写UserDAO的代码: BorfEv} SN
3. UserDAO 和 UserDAOImpl: =|{,5="
java代码: C)3$";$5)
*V@MAt
n'ca*E(
/*Created on 2005-7-15*/ `bt)'ERO%#
package com.adt.dao; {</$ObK
xz+`]Q
import java.util.List; uTlT'9)
- m x3^
import org.flyware.util.page.Page; o}^vREO
hk$nlc|$
import net.sf.hibernate.HibernateException; Uf]Pd)D
b8b PK<
/** ofrlTw&o
* @author Joa OrH1fhh
*/ oWaIjU0
publicinterface UserDAO extends BaseDAO { ^%OH}Z `ly
JpHsQ8<
publicList getUserByName(String name)throws U+}9X^
_~#C $-T
HibernateException; 7Hkf7\JY
Y"\T*lKa
publicint getUserCount()throws HibernateException; {^19.F
N n-6/]d#
publicList getUserByPage(Page page)throws [;LPeO
+fQ$~vr{'
HibernateException; R\Ynn^w
90if:mYA
} H2_>Av{m
xg5@;p
7u3b aM
ToXFMkwY
C"|_j?
java代码: d=OO(sf
9DAwC:<r
9M~$W-5
/*Created on 2005-7-15*/ wm`"yNbD
package com.adt.dao.impl; ^EBM;&;7
9l^
import java.util.List; cZ2,
u,4
j\L$dPZ
import org.flyware.util.page.Page; l#f]KLv4N_
a|{<#<6n(
import net.sf.hibernate.HibernateException; (2\ekct ^
import net.sf.hibernate.Query; UlZ)|Ya<M
Ytnr$*5.
import com.adt.dao.UserDAO; ,^[37/S
B-p5;h>
/** (S 3kP5:F
* @author Joa WG=r? xE
*/ en6AAr:U}
public class UserDAOImpl extends BaseDAOHibernateImpl ieoUZCO^r\
X_S]8Aa
implements UserDAO { h pes
?Lb7~XKt\
/* (non-Javadoc) bN%MT#X
* @see com.adt.dao.UserDAO#getUserByName x(6.W"-S
`l40awGCz
(java.lang.String) WSccR
*/ 7uH{UpslJ
publicList getUserByName(String name)throws @!HMd{r
hUvH
t+d
HibernateException { ]-OkW.8d1
String querySentence = "FROM user in class RwHXn]1
yAkN2
com.adt.po.User WHERE user.name=:name"; WZ-{K"56
Query query = getSession().createQuery Z+Zh;Ms
R.$Y1=U6
(querySentence); /P}tgcs
query.setParameter("name", name); pODo[Rkq
return query.list(); D)$k{v#~
} !H.lVA
tELnq#<6
/* (non-Javadoc) 3ZZI1_j
* @see com.adt.dao.UserDAO#getUserCount() K`2DhJC
*/ ozwqK oE
publicint getUserCount()throws HibernateException { /'+JP4mK
int count = 0; +@v} (
String querySentence = "SELECT count(*) FROM E&v-(0
A|nU
_*
user in class com.adt.po.User"; $
$+z^%'_
Query query = getSession().createQuery +6E<+-N
,urkd~
(querySentence); +T;qvx6
count = ((Integer)query.iterate().next f
8U;T$)
sTY l' Ieg
()).intValue(); *xKR;?.
return count; 0 ']M,iC/
} Stx-(Kfn4
co-D,o4x
/* (non-Javadoc) I[ C.iILL
* @see com.adt.dao.UserDAO#getUserByPage P1jkoJ
3F3?be
(org.flyware.util.page.Page) `;hBO#(H0}
*/ 4K% YS
publicList getUserByPage(Page page)throws % QkvBg*
:v48y.Ij7s
HibernateException { jlZNANR3
String querySentence = "FROM user in class ymqhI\>y#
@UBp;pb}=h
com.adt.po.User"; h@8
Query query = getSession().createQuery CiFbk&-g
? 'nMZ
(querySentence); {QJ`.6Kt
query.setFirstResult(page.getBeginIndex()) _E7eJSM.
.setMaxResults(page.getEveryPage()); $S/ 8T
return query.list(); 3+'w% I
} "b;?2_w:E
=#Jb9=zdR
} ujBADDwOg)
x;/3_"$9>\
d?qz7#kc
4|UIyDt8
AmFHn
至此,一个完整的分页程序完成。前台的只需要调用 HC$cK+,ZU}
uR[i9%=8L(
userManager.listUser(page)即可得到一个Page对象和结果集对象 c{0?gt.
9`{cX
的综合体,而传入的参数page对象则可以由前台传入,如果用 u^$ CR
2
r)c?
webwork,甚至可以直接在配置文件中指定。 M~4!gKs
w.jATMJ)F
下面给出一个webwork调用示例: }K\_N]#6n
java代码: NgQl;$
Kk#@8h>
#;)7~69
/*Created on 2005-6-17*/ ]
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package com.adt.action.user; <dZ{E7l
0%GWc}o
import java.util.List; {z7{ta
rXMv&]Ag
import org.apache.commons.logging.Log; lPQH_+)Z"
import org.apache.commons.logging.LogFactory; f.{0P-Np
import org.flyware.util.page.Page; e#
DAa
n >^?BU
import com.adt.bo.Result; _nt%&f
import com.adt.service.UserService; 8~bPoWP
import com.opensymphony.xwork.Action; E*$:~w
C%&7,F7
/** okW3V}/x/z
* @author Joa , /pE*Yk
*/ k dqH36&<
publicclass ListUser implementsAction{ 4#T'Fy].
XN Y(@
privatestaticfinal Log logger = LogFactory.getLog TFhj]r^{
b({2|R
(ListUser.class); `@90b4u
=[$*PTe
private UserService userService;
J' ;tpr
p ,!`8c6
private Page page; pGC`HTo|
+RM3EvglDQ
privateList users; tP UQ"S
+1Uw <~
/* hN.#ui5 $
* (non-Javadoc) rtI4W
* ^ZsME,
* @see com.opensymphony.xwork.Action#execute() 9:Y\D.M
*/ 4-\a]"c
publicString execute()throwsException{ SOm~];[
Result result = userService.listUser(page); `:2C9,Xu
page = result.getPage(); Vo\d&}Q
users = result.getContent(); Gp14;
return SUCCESS; LRs{nN.N
} `yhL11]~
E,;nx^`!l
/** %w@(V([(c
* @return Returns the page. 1>Op)T>{c
*/ =\3*;59\
public Page getPage(){ (z[cf|he
return page; :KFhryN
} XDn$=`2
T]:5y_4?[
/** H;^6%HV1
* @return Returns the users. \3KCZ
*/ `@ObM[0p(
publicList getUsers(){ {>i'Pb0mG|
return users; v4&*iT
} 5W'T7asOh
R_^:<F0
/** d&fENnt?h
* @param page B!5gD
* The page to set. r4-r
z+x
*/ jj^CW"IB
publicvoid setPage(Page page){ Q|0[B4e^:
this.page = page; m\t
%wr
} `a J[
!O
2@ad! h
/** -Oo$\=d
* @param users 5%Q!R%
* The users to set. A}%sF MA
*/ 8mV35A7l
publicvoid setUsers(List users){ F4k`x/ak
this.users = users; :!R+/5a
} ,e;(\t:
3
-5^$-7_
/** 67#;.}4a
* @param userService 6L2.88 i
* The userService to set. ^v,^.>P
*/ rR7}SEa
publicvoid setUserService(UserService userService){ m1(rAr1
this.userService = userService; dkXK0k
} 7==Uoy*O
} 4g6d6~098;
eX=W+&lj
AttDD{Ta
Q%85,L^ U
lwK Au!l
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, [1E u6X6
nJ6bC^*)U
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ub-ZrC'
Pp}j=$&j\
么只需要: `InS8PLr
java代码: U?kJXM2
kefQH\<X
?&N
JN/+%
<?xml version="1.0"?> #vIF]Y
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork IQR?n}ce
wc ^z9y
1.0//EN" "http://www.opensymphony.com/xwork/xwork- wL}=$DN
f#[Fqkmj
1.0.dtd"> kQYX[e7n
2r1.,1
<xwork> Fd3V5h
N5g!,3
<package name="user" extends="webwork- 0{ \AP<
Q|;8\5
interceptors"> iLgWzA
Yw./V0Z{@
<!-- The default interceptor stack name ' (ql7
xvb5-tK
-
--> oas}8A)
<default-interceptor-ref f 1]1ZOb
}VyDX14j
name="myDefaultWebStack"/> xFgY#F
h_H$+!Nzb
<action name="listUser" TJ+yBMd*%
3C5<MxtK
class="com.adt.action.user.ListUser"> edA.Va|0
<param :dB6/@fW
ZXp=QH+f
name="page.everyPage">10</param> V,lz}&3L
<result y_QK _R<