Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ~<<32t'S:
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 \^9n&MonM
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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 aW dI
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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 h%u!UHA
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分页支持类: $mKExW
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java代码: dF 6od
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package com.javaeye.common.util; Hs8JJGXWB
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import java.util.List; D:j5/ *
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publicclass PaginationSupport { zL}`7*d:v
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publicfinalstaticint PAGESIZE = 30; RAu(FJ
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privateint pageSize = PAGESIZE; G)NqIur*Z
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privateList items; q {
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privateint totalCount; 5655)u.N8
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privateint[] indexes = newint[0]; ^4,LIIUj
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privateint startIndex = 0; ! jApV
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public PaginationSupport(List items, int u@:[ dbJ
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totalCount){ Q6URaw#Yt`
setPageSize(PAGESIZE);
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setTotalCount(totalCount); A9]&w
setItems(items); KwaxNb5
setStartIndex(0); o-&0_Zq_
} p>J@"?%^
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public PaginationSupport(List items, int R#y"SxD()
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totalCount, int startIndex){ ]G8"\J4 &
setPageSize(PAGESIZE); >0iCQKq
setTotalCount(totalCount); wE<r'
setItems(items); lcEK&AtK
setStartIndex(startIndex); GNuIcy
} |Bi7:w
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public PaginationSupport(List items, int ^^!G{*F
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totalCount, int pageSize, int startIndex){ ci2Z_JA+
setPageSize(pageSize); Ylu\]pr9|C
setTotalCount(totalCount); 6XCFL-o-
setItems(items); T+RC#&>
setStartIndex(startIndex); yDZm)|<.
} 4bw4!z9G
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publicList getItems(){ r: >RH,
return items; .w{Y3,dd>
} s3@mk\?qMe
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publicvoid setItems(List items){ ]o=ON95ja
this.items = items; }!Pty25j
} 2)0J@r'
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publicint getPageSize(){ :HrFbq
return pageSize; ?tqJkL#
} S#y GqN0i
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publicvoid setPageSize(int pageSize){ \ %MsG
this.pageSize = pageSize; :O&jm.2m
} o6~JAvw
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publicint getTotalCount(){ [~\]<;;\
return totalCount; z'1%%.r;FM
} ]i0=3H2
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publicvoid setTotalCount(int totalCount){ -$g~,dIwj
if(totalCount > 0){ Os9EMU$
this.totalCount = totalCount; KDGrX[L:6
int count = totalCount / 'PFjZGaKR
FAM:; F30
pageSize;
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if(totalCount % pageSize > 0) @+p(%
count++; )Qe]!$tqfD
indexes = newint[count]; mPQT%%MF
for(int i = 0; i < count; i++){ {=Jo!t;f
indexes = pageSize * q I~*G3
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} }
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}else{ =23@"ji@D
this.totalCount = 0; (^g XO
} P*|=Z>%[0
} Ac|dmu
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publicint[] getIndexes(){ \~Z%}$ =
return indexes; a:HN#P)12
} O_.!qk1R
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publicvoid setIndexes(int[] indexes){ C%]qK(9vvd
this.indexes = indexes; >D~8iuy]8.
} UyV5A
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publicint getStartIndex(){ hp9LV2_5
return startIndex; 7_)38
} VX8CEO
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publicvoid setStartIndex(int startIndex){ >s"/uo
if(totalCount <= 0) Pz:,de~5Qm
this.startIndex = 0; h:?qd
elseif(startIndex >= totalCount) m$v >r\*X
this.startIndex = indexes i+~BVb
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[indexes.length - 1]; 5 *YvgB;
elseif(startIndex < 0) w4TQ4
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this.startIndex = 0; GtZ.'?-
else{ 2;:p
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this.startIndex = indexes a`f@&A`z
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[startIndex / pageSize]; dc1Zh
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} iJ8Z^=>
} .7b%7dQ<\
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publicint getNextIndex(){ DQXcf*R
int nextIndex = getStartIndex() + Xz)F-C27h
v3M$UiN,:
pageSize; F4z#u2~TC
if(nextIndex >= totalCount) g\.$4N
return getStartIndex(); =QtFJ9\
else xYYa%PhIC
return nextIndex; \6?a
} K#X/j'$^
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publicint getPreviousIndex(){ N AY3.e
int previousIndex = getStartIndex() - YOGj__:
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pageSize; /P TRe5-7
if(previousIndex < 0) =dKjTBR S'
return0; jTt9;?)
else d*gv.mE
return previousIndex; ; xp-MK
} <YU4RZ
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} t $Rc
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抽象业务类 'gs P9
java代码: s*yl&El/
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/** =VuSi(d;e{
* Created on 2005-7-12 3lpxh_
*/ ~:T@SrVI
package com.javaeye.common.business; ,
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import java.io.Serializable; ^-k"gLg
import java.util.List; AK&>3D
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import org.hibernate.Criteria; ~KMah
import org.hibernate.HibernateException; DWKQ>X6
import org.hibernate.Session; Z8xB
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import org.hibernate.criterion.DetachedCriteria; .aY$-Y<
import org.hibernate.criterion.Projections; )< G(C,!,.
import I)FFh%m<}a
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org.springframework.orm.hibernate3.HibernateCallback; fy"}#
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import #c@&mus
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org.springframework.orm.hibernate3.support.HibernateDaoS nD*iSb*
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upport; 65~E<)UJ
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import com.javaeye.common.util.PaginationSupport; YWH>tt9
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public abstract class AbstractManager extends n
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HibernateDaoSupport { <6 Rec^QF
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privateboolean cacheQueries = false; @y;VV*
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privateString queryCacheRegion; 8N'hG,
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publicvoid setCacheQueries(boolean raPOF6-_rH
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cacheQueries){ lgU!D |v
this.cacheQueries = cacheQueries; \]Ah=`
} Ex
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publicvoid setQueryCacheRegion(String c 1F^Gj!8
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queryCacheRegion){ Nz`8)Le
this.queryCacheRegion = [6mK<A,/
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queryCacheRegion; J2VPOn
} ~+4lmslR
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publicvoid save(finalObject entity){ f~mwDkf?L
getHibernateTemplate().save(entity); qK%N{ro[{?
} 8+oc4~!A@n
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publicvoid persist(finalObject entity){ iw,uwh|L
getHibernateTemplate().save(entity); .euAN8L
} nb/q!8
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publicvoid update(finalObject entity){ j
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getHibernateTemplate().update(entity); )?[7}(4jI
} QZvQ8
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publicvoid delete(finalObject entity){ 7Fo^:"
getHibernateTemplate().delete(entity); !I?C8)
} ,V9qiu=m
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publicObject load(finalClass entity, PdO"e
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finalSerializable id){ GW>F:<p
return getHibernateTemplate().load im&N&A
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(entity, id); /W,hOv
} ; j.d
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publicObject get(finalClass entity, zS;ruK%2
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finalSerializable id){ A` _dj}UF
return getHibernateTemplate().get tP|/Q5s
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(entity, id); 2Ty]s~
} _=I1
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publicList findAll(finalClass entity){ !8UIyw
return getHibernateTemplate().find("from o$L%t@
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" + entity.getName()); JR`$t~0t
} aWTurnee^
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publicList findByNamedQuery(finalString ^?Xs!kJP
n! 5(Z5=
namedQuery){ O)&W0`VY
return getHibernateTemplate PR|z -T
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().findByNamedQuery(namedQuery); P,] ./m\J
} ~vDa2D<9%
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publicList findByNamedQuery(finalString query, *ilh/Hd>
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finalObject parameter){ nQV0I"f]?]
return getHibernateTemplate Vc5>I_
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().findByNamedQuery(query, parameter); EoJ\Jk
} i;{lY1
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publicList findByNamedQuery(finalString query, \}h
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finalObject[] parameters){ yC$m(Y12FN
return getHibernateTemplate eef&ZL6g
>(P(!^[f
().findByNamedQuery(query, parameters); `oNJ=,p
} 3 orZBT
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publicList find(finalString query){ 6HBDs:
return getHibernateTemplate().find u3qxG3
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(query); E`_T_O=P
} G?@W;o)
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publicList find(finalString query, finalObject nxhlTf>3
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parameter){ M7?ktK9`ma
return getHibernateTemplate().find M>5OC)E
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(query, parameter); (/$-2.@
} XgX~K:<jt
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public PaginationSupport findPageByCriteria ^cNuEF9
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(final DetachedCriteria detachedCriteria){ ) ??N]V_U
return findPageByCriteria J:W+'x`@
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); %ZD]qaU0
} y}oA!<#3
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public PaginationSupport findPageByCriteria TaSS) n
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(final DetachedCriteria detachedCriteria, finalint w( SY
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startIndex){ }v}F8}4
return findPageByCriteria I)1ih
}0\SNpVN
(detachedCriteria, PaginationSupport.PAGESIZE, D$4GNeB+#
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startIndex); ` Ny(S2
} Qq.$!$
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public PaginationSupport findPageByCriteria >}F$6KM
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(final DetachedCriteria detachedCriteria, finalint ?xUl_
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pageSize, Xj+_"0
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finalint startIndex){ p5E
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return(PaginationSupport) _Ycz@Jn
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getHibernateTemplate().execute(new HibernateCallback(){ d+)L K~
publicObject doInHibernate $!. [R}
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(Session session)throws HibernateException { K_Y{50#
Criteria criteria = +|bmUm<2
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detachedCriteria.getExecutableCriteria(session); H0inU+Ih
int totalCount = qspGNu
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((Integer) criteria.setProjection(Projections.rowCount p_BG#dRM
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()).uniqueResult()).intValue(); 16eP7s
criteria.setProjection JdI*@b2k[
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(null); 5!9y nIC+>
List items = 8*&-u +@%
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criteria.setFirstResult(startIndex).setMaxResults W (TTsnnx
+&"W:Le:
(pageSize).list(); z5({A2q
PaginationSupport ps = q*R~gEi#yk
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new PaginationSupport(items, totalCount, pageSize, w7~]c,$y.
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startIndex); rkS'OC
return ps; \I i#R
} ;(,GS@sP
}, true); l]DRJ
} !V #*(_+n
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public List findAllByCriteria(final u*iqwm.
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DetachedCriteria detachedCriteria){ (*eX'^Q)d
return(List) getHibernateTemplate |:(B I5&S
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().execute(new HibernateCallback(){ 24InwR|^
publicObject doInHibernate )N{PWSPs
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(Session session)throws HibernateException { 4ybOK~z
Criteria criteria = uq:'`o-1
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detachedCriteria.getExecutableCriteria(session); Jp)PKS
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return criteria.list(); A+Je?3/.
} Vx0Hq`_14
}, true); ,9=P=JH
} #9"lL1
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public int getCountByCriteria(final 25, [<Ao
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DetachedCriteria detachedCriteria){ <C"}OW8
Integer count = (Integer)
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getHibernateTemplate().execute(new HibernateCallback(){ c:z}$DK&'
publicObject doInHibernate k3OnvnJb
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(Session session)throws HibernateException { 3kJSz-_M
Criteria criteria = Grd9yLF
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detachedCriteria.getExecutableCriteria(session); %ULd_ES^
return 1d.>?^uE
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criteria.setProjection(Projections.rowCount jS/$o ?
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()).uniqueResult(); dnPr2oI?I
} E\}Q9,Z$
}, true); WWTJ%Rd|
return count.intValue(); p|*b] 36
} <* PjG}Z.
} iN`L* h
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用户在web层构造查询条件detachedCriteria,和可选的 3^&pb
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 zwHTtE
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PaginationSupport的实例ps。 `+@%l*TQ
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ps.getItems()得到已分页好的结果集 .^1=*j(;
ps.getIndexes()得到分页索引的数组 C[$<7Mi|;
ps.getTotalCount()得到总结果数 BQ&h&57K
ps.getStartIndex()当前分页索引 %nc+VL4
ps.getNextIndex()下一页索引 ` }Hnj*
ps.getPreviousIndex()上一页索引 EA>$t\z
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 pV-.r-P
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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 cRfX
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一下代码重构了。 J<zg 'Jk^
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我把原本我的做法也提供出来供大家讨论吧: 1Q;`<=
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首先,为了实现分页查询,我封装了一个Page类: Ia"bP` L
java代码: mg;AcAS.o,
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/*Created on 2005-4-14*/ dX3>j{_
package org.flyware.util.page; Cw2+@7?|
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/** =UP)b9*h
* @author Joa MR6vr.~
* ?8nG F%p
*/ M*{e e0\`r
publicclass Page { 4%{m7CK}
*ZEs5`x
/** imply if the page has previous page */ MdfkC6P
privateboolean hasPrePage; U5PCj ]-Xt
/kq~*s
/** imply if the page has next page */ x[kdQj2[&
privateboolean hasNextPage; %~[F^
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/** the number of every page */ n#fg7d%
privateint everyPage; pL-$Np] V
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/** the total page number */ ;Os3
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privateint totalPage; GgYomR:
7> Qt O
/** the number of current page */ fe$WR~
privateint currentPage; -|kDa1knA
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/** the begin index of the records by the current ~}11 6K
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query */ G#C)]4[n
privateint beginIndex; s'^#[%EgB
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/** The default constructor */ b,W'0gl
public Page(){ cG'Wh@
{m?x},
} o5R\7}]GE
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/** construct the page by everyPage )Fw)&5B!
* @param everyPage 8FITcK^
* */ qG qu/$bh
public Page(int everyPage){ m @%|Q;
this.everyPage = everyPage; U{Z>y?V/
} dw|0K+-PH
@n(In$
/** The whole constructor */ [C6?:'}FA
public Page(boolean hasPrePage, boolean hasNextPage, e{,/
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int everyPage, int totalPage, 96avgyc
int currentPage, int beginIndex){ wW4S@m
this.hasPrePage = hasPrePage; :S12=sFl$
this.hasNextPage = hasNextPage; !)=o,sVA
this.everyPage = everyPage; O~el2
this.totalPage = totalPage; 8E+l;2
this.currentPage = currentPage; Izu.I_$4
this.beginIndex = beginIndex; w$4Lu"N:
} (% P=#vZ
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/**
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* @return [Bo$?
* Returns the beginIndex. D.b<I79bX
*/ MV}]i@V
publicint getBeginIndex(){ #Au&2_O
return beginIndex; rYQ@"o0/Y
} )[*O^bPowI
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/** *
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* @param beginIndex 0)!zhO_}
* The beginIndex to set. uw!|G>
*/ :F=nb+HZ
publicvoid setBeginIndex(int beginIndex){ S+Yg!RrNqj
this.beginIndex = beginIndex; vM/v}6;_K2
} ".?{Y(~
GcW}<g}
/** ;7k7/f:
* @return 8zWPb
* Returns the currentPage.
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*/ `F 8;{`a
publicint getCurrentPage(){ Vz]=J;`Mz
return currentPage; I >Q,]S1h
} z_@zMLs
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/** Els= :4
* @param currentPage {C6;$#7P
* The currentPage to set. ?
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*/ mtddLd,
publicvoid setCurrentPage(int currentPage){ \r,.hUp
this.currentPage = currentPage; Ky$G$H
} %0]b5u
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/** .6o y>4
* @return ilpZ/Rs
* Returns the everyPage. O/oYaAlFF@
*/ s,H(m8#>
publicint getEveryPage(){ .fY<"2g
return everyPage; AiK4t-
} Z3>3&|&
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/** ^)^|;C\`
* @param everyPage _6zP]|VBr
* The everyPage to set. kTc5KHJ7
*/ 9XvM%aHs:
publicvoid setEveryPage(int everyPage){ n4T2'e
this.everyPage = everyPage; {eN{Zh5"
} vqz#V=J{
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/** SLOYlRGCi
* @return i}F;fWZ`
* Returns the hasNextPage. '4lT*KN7\
*/ }SN44 di(
publicboolean getHasNextPage(){ 3l(;Pt-yI
return hasNextPage; PG[O?l
} BBE1}V!u
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/** G:C6`uiy`
* @param hasNextPage <;0N@
* The hasNextPage to set. ^I~T$YjC '
*/ ::Q);
publicvoid setHasNextPage(boolean hasNextPage){ NF(IF.8G
this.hasNextPage = hasNextPage; HT=Am
} Q*&aC|b&
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/** gXLZ) >+A+
* @return /Q>{YsRRB
* Returns the hasPrePage. t,1! `/\
*/ 2G}7R5``9
publicboolean getHasPrePage(){ ;E? hz
return hasPrePage; v\9,j
} 4OZ5hH
h
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/** XvkI+c
* @param hasPrePage Ed0>R<jR9
* The hasPrePage to set. kPX2e h
*/ R{xyme@"^
publicvoid setHasPrePage(boolean hasPrePage){ BOiz ~h6
this.hasPrePage = hasPrePage; NuS|X
} iraRB~
*[1u[H9Cv
/** cYWy\+
* @return Returns the totalPage. BXK::M+
* vXM/nw|5
*/ ['Y+z2k
publicint getTotalPage(){ R4~zL!7;
return totalPage; rq(~/Yc
} #C,f/PXfaB
^'u;e(AaE
/** 51ajE2+X&
* @param totalPage eFj6p<
* The totalPage to set. ADv"_bB:h
*/ Neo^C_[vN
publicvoid setTotalPage(int totalPage){ Vyt~OTI\
this.totalPage = totalPage; ,8xP8T~Kmv
} gR-Qj
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} h\u0{!@}
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Mi/ &$"=
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 ZH;y>Z
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个PageUtil,负责对Page对象进行构造: Y0X"Zw
java代码: Bd[L6J)
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/*Created on 2005-4-14*/ FfYd+]+?
package org.flyware.util.page; "Ql}Y1
=,AC%S_D~
import org.apache.commons.logging.Log; }ED
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import org.apache.commons.logging.LogFactory; ?9(o*lp
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/** %7NsBR!y
* @author Joa ^)hAVf~E
* &'huS?gA9
*/ $/, BJ/9
publicclass PageUtil { { p!_-sL
YH'$_,8peM
privatestaticfinal Log logger = LogFactory.getLog CrNwALx
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(PageUtil.class); SY$J+YBLM
(@KoqwVWc
/** " xDx/d8B
* Use the origin page to create a new page |-(IJG#)
* @param page A[^qq UL'
* @param totalRecords *?^Z)C>
* @return ]3O
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*/ CYPazOfj
publicstatic Page createPage(Page page, int " K 8&{=
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totalRecords){ >Lw}KO`
return createPage(page.getEveryPage(), 4#^'lKIx
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page.getCurrentPage(), totalRecords); :M22P`:
} ~!nLbK2
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/** [F/^J|VMV
* the basic page utils not including exception f{y]
*M>
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handler -ajM5S=d*
* @param everyPage "t[M'[ `C
* @param currentPage QP6z?j.
* @param totalRecords M11"<3]D
* @return page xab]q$n]k
*/ NXzU0
publicstatic Page createPage(int everyPage, int
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currentPage, int totalRecords){ Q7,EY /
everyPage = getEveryPage(everyPage); 8G 0
currentPage = getCurrentPage(currentPage); ! jbEm8bt
int beginIndex = getBeginIndex(everyPage, 5/& 1Oxo
cPpu
currentPage); nK+lE0
int totalPage = getTotalPage(everyPage, I2TD.wuIW
9o-!ecx}
totalRecords); OSp?okV
boolean hasNextPage = hasNextPage(currentPage, :{[<g](
[RAj3Fr0
totalPage); %x&F4U
boolean hasPrePage = hasPrePage(currentPage); 2HcsQ*H]G
j((hqJr
returnnew Page(hasPrePage, hasNextPage, '5'3_vM
everyPage, totalPage, ZhH+D`9
currentPage, {mNdL J
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beginIndex); y^2#9\}K
} vG Y!4@[
Vy]A,Rn7
privatestaticint getEveryPage(int everyPage){ +'-rTi\
return everyPage == 0 ? 10 : everyPage; ($c`s8mp
} 5^\m`gS
m"n.Dz/S
privatestaticint getCurrentPage(int currentPage){ JW=uK$s O
return currentPage == 0 ? 1 : currentPage; e#tIk;9Xz
} QQ@9_[N
4[`[mE18.
privatestaticint getBeginIndex(int everyPage, int 8KFj<N>'
d!o.ASL{
currentPage){ z1F9$^
return(currentPage - 1) * everyPage; yL.^ =
} Zp`~}LV{
<nBo}0O}
privatestaticint getTotalPage(int everyPage, int `%|u!
XTV0Le\f
totalRecords){ im=5{PbJ^
int totalPage = 0; 5? Wg%@
2xDQ:=ec
if(totalRecords % everyPage == 0) pDGT@qJ
totalPage = totalRecords / everyPage; `aIG;@Z
else _74UdD{^o
totalPage = totalRecords / everyPage + 1 ; H.:9:I[n
aVP5%
return totalPage; EJ G2^DSS
} wS V@=)H\:
3Y`>6A=
privatestaticboolean hasPrePage(int currentPage){ ZPlPN;J^1
return currentPage == 1 ? false : true; D i+4Eb
} M+0x;53nz
mf}\s]_c
privatestaticboolean hasNextPage(int currentPage, g92dw<$>
gwiR/(1
int totalPage){ /l^y}o %?
return currentPage == totalPage || totalPage ==
YZ<
NP
X@!X6j
0 ? false : true; FuuS"G,S
} Ir/:d]N*
!N1J@LT5h
Atd1qJ
} KSc~GP_
bEd?^h
t@)my[ !
x6ahZ
<7^Kt7k
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。 i
j/o;_
3za`>bUN
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 &\k?xN
$T),DUYO
做法如下: 9 ZGV%Tw
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 tq&Yek>C
WNa3^K/W{
的信息,和一个结果集List: !!WJn}
java代码: 9 #Y2`pT
< eQ[kM
6.'$EtH
/*Created on 2005-6-13*/ j&CZ=?K^c
package com.adt.bo;
RL*]g*
P>wZ~Hjk
import java.util.List; 2h)8Fq_"
/lJjQ]c;>
import org.flyware.util.page.Page; g/#~N~&
JT)k
/** K2HvI7$-
* @author Joa eu9w|g
*/ $)*xC!@6X
publicclass Result { 2r;GcjezH
?E7=:h(@t
private Page page; uNbIX:L,
&z>q#'X;.
private List content; JYV\oV{
tpo>1|
/** o1k#."wHr
* The default constructor ^f|<R8 `
*/ 7/"@yVBW
public Result(){ h0Jl_f#Y
super(); d}-'<Z#G
} -:SIS`0s
jDTUXwx7V
/** S+ebO/$>
* The constructor using fields iBoEZEHjw
* J3=BE2L
* @param page j Nc<~{/
* @param content W:O0}
*/ ^|?1_r
public Result(Page page, List content){ |I^y0Q:K
this.page = page; Spgg+;9
this.content = content; Hk u=pr3Gn
} _Adsq8sFW
w$>3pQ8d
/** Rd%0\ B
* @return Returns the content. ezZph"&
*/ ETp'oh}?
publicList getContent(){ f#P_xn&et
return content; O2 v.
} +'XhC#:
J+Bdz6lt
/** d(S}NH
* @return Returns the page. ^>m^\MuZ
*/ gs`> C(
public Page getPage(){ 3eKQ<$w
return page;
%+wF"
} frqJN
lIh[|]
/** ]k*1KP
* @param content ``9 GY
* The content to set. ~lw<799F6
*/ *48IF33&s
public void setContent(List content){ };sMU6e
this.content = content; |+NuYz?
} z+3 9ee
I7mG/
/** M<[?g5=#
* @param page 'm O2t~n
* The page to set. NHkL24ve
*/ Zq*eX\#C
publicvoid setPage(Page page){ Wsm`YLYkt!
this.page = page; o~C('1Fdb
} &iSD/W
} "s]y!BLk
SI*^f\lu
onl>54M^
#D)x}#V\
>n!ni(
2. 编写业务逻辑接口,并实现它(UserManager, s#^pC*,'
\##`pa(8
UserManagerImpl) @G GccF
java代码: C5n?0I9
ZnXejpj)D
arh@`'Q
/*Created on 2005-7-15*/ {4rQ7J4Ux
package com.adt.service; \0AiCMX[
TnE+[.Qu
import net.sf.hibernate.HibernateException; >o[|"oLO
yP\Up
import org.flyware.util.page.Page; 0"4@;e_)>
FA$zZs10\
import com.adt.bo.Result; nyhMnp#<
,7,;twKz
/** O9]\Q@M.
* @author Joa i'tp1CI
*/ xl]
;*&
publicinterface UserManager { slvq9,
8/Rm!.8+~
public Result listUser(Page page)throws h~miP7,c<u
h&'=F)5
HibernateException; .3wY\W8Dr-
?R6`qe_F
} vA-PR&
' G#SLqZy
Y}.Ystem
p&3>
`C
xP@/9SM
java代码: FH\CK
Hg(5S,O2
>q(6,Mmb
/*Created on 2005-7-15*/ QIA R
package com.adt.service.impl; ./w{L"E
iBvOJs
import java.util.List; K{L.ZH>7
\P?A7vuhLs
import net.sf.hibernate.HibernateException; w0Ij'=:
;CmOsA,1
import org.flyware.util.page.Page; H/jm
f5
import org.flyware.util.page.PageUtil; #IX&9 aFB}
XxOn3i
import com.adt.bo.Result; (cs~@
import com.adt.dao.UserDAO; mk= #\>
import com.adt.exception.ObjectNotFoundException; 3j*'HST
import com.adt.service.UserManager; #s+Q{2s
.~`Y)PON
/** .#!mDlY;
* @author Joa ~B_ D@gV|
*/ RvW.@#EH0
publicclass UserManagerImpl implements UserManager { \ X$)vK
9}
*$n&B
private UserDAO userDAO; t)I0lnbs
kxo.v |)8
/** IVteF*8hU
* @param userDAO The userDAO to set. ct0v$ct>f
*/ -,GEv%6c
publicvoid setUserDAO(UserDAO userDAO){ Bp3L>AcVu
this.userDAO = userDAO; (,LL[&;:
} *Nlu5(z
%dmfBf Ev
/* (non-Javadoc) ;$;rD0i|
* @see com.adt.service.UserManager#listUser u^=@DO'
c]v
+
(org.flyware.util.page.Page) N!m%~kS9k<
*/ fn1pa@P
public Result listUser(Page page)throws 3; y_mg
Dl\d_:+
HibernateException, ObjectNotFoundException { z%};X$V`J
int totalRecords = userDAO.getUserCount(); AgsR-"uh
if(totalRecords == 0) S=O$JP79
throw new ObjectNotFoundException 1+^n!$
Ab
g$W/(|
("userNotExist"); B] i:)
page = PageUtil.createPage(page, totalRecords); m!Af LSlwm
List users = userDAO.getUserByPage(page); -eL'KO5'
returnnew Result(page, users); HRHrSf7
} ifrq
/"MJkM.~E
} U Um|@
\7
Mq $d
stXda@y<p
PP-kz;|
\`gEu{
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 UE7'B?
T6=-hA^A
询,接下来编写UserDAO的代码: \HG$V>2
3. UserDAO 和 UserDAOImpl: CJA+v-
java代码: ~04[KG
8uA<G/Q;
K;C_Z/<%
/*Created on 2005-7-15*/ p`p?li
package com.adt.dao; 9K$]h2
yoW>
BX
import java.util.List; 8t\}c6/3"
pK"&QPv
import org.flyware.util.page.Page; LE|<O
>)y$mc6
import net.sf.hibernate.HibernateException; 1RA }aX
l/F!Bq[*g
/** G"C;A`6
* @author Joa 0BDoBR
*/ 1M/$<
kQ-N
publicinterface UserDAO extends BaseDAO { Gc^t%Ue-H)
x~Cz?ljbn
publicList getUserByName(String name)throws m9Il\PoTq
mR,O0O}&
HibernateException; _XWnS9
a7=YG6[
publicint getUserCount()throws HibernateException; jYk5~<\k
~4+8p9f
publicList getUserByPage(Page page)throws 19&)Yd1
_'lmCj8L
HibernateException; dm 2EH
|Q6h/"2
} [%?hCc
&L'6KEahR
b?>VPuyBb
Oc~VHT
<K,[sy&Qy
java代码: N5ci};?
]f5c\\)
Onyh1
/*Created on 2005-7-15*/ g+3Hwtl
package com.adt.dao.impl; J7Sx!PQ
GqMB^Ad
import java.util.List; =tHD 4I
c l9$g7
import org.flyware.util.page.Page; c`pYc
P]-#wz=S
import net.sf.hibernate.HibernateException; s_S$7N`ocS
import net.sf.hibernate.Query; :U8k|,~f
>-eS&rma
import com.adt.dao.UserDAO; 2=O))^8
<a fO 6?`
/** z:?:
* @author Joa r;$r=Uf r
*/ IBDVFA
public class UserDAOImpl extends BaseDAOHibernateImpl 03C .Xh=!
=CE HRny
implements UserDAO { vU7&'ca
R7,pukK
/* (non-Javadoc) 8a?IC|~Pz
* @see com.adt.dao.UserDAO#getUserByName \Me"'.F?
vyujC`61d
(java.lang.String) g(1"GKg3K
*/ fH; |Rm
publicList getUserByName(String name)throws VYHOk3
o;E(Kj
HibernateException { !#C)99L"F
String querySentence = "FROM user in class ML"_CQlE7
fG3wc
l~
com.adt.po.User WHERE user.name=:name"; " xlJs93c
Query query = getSession().createQuery =#jTo|~u4o
b#e]1Q
(querySentence); p0
query.setParameter("name", name); }!Xf&c{7{
return query.list(); QP'qG@j[:
} =%xIjxYl
0,bt^a
/* (non-Javadoc) d4Ixuux<3
* @see com.adt.dao.UserDAO#getUserCount() 2lF WW(
*/ gNG.l
publicint getUserCount()throws HibernateException { r!CA2iK`
int count = 0; vs*>onCf
String querySentence = "SELECT count(*) FROM dP?nP(l
y(V&z"wk[
user in class com.adt.po.User"; PE^eP}O1
Query query = getSession().createQuery Tq.MubaO
<1TlW
~q<
(querySentence); 1<;\6sg
count = ((Integer)query.iterate().next 2-QuT"Gkd
|C^
c0
()).intValue(); 3/SfUfWo
return count; @T9m}+fR
} 9zmD6G!}t
l#
}As.o}
/* (non-Javadoc) ]6jHIk|
* @see com.adt.dao.UserDAO#getUserByPage fLLnf].O
]r"31.w(
(org.flyware.util.page.Page) ~ W2:NQ>i
*/ #($k 3OA
publicList getUserByPage(Page page)throws [8{_i?wY
Z83q-
HibernateException { &8pCHGmV)
String querySentence = "FROM user in class [lmHXf@1C
+ 8MW$ m$
com.adt.po.User"; VaOpO8y`
Query query = getSession().createQuery Y:DNu9
SD)5?{6<
(querySentence); em f0sL
query.setFirstResult(page.getBeginIndex()) EGp~Vo-
.setMaxResults(page.getEveryPage()); >1#DPU(g
return query.list(); >xhd[
} M!;`(_2
x.j Yip
} 6n2Vx1b
i{Y=!r5r
w`H.ey
.=.yZ
L7~+x^kw
至此,一个完整的分页程序完成。前台的只需要调用 ?^+#pcX]t|
pko!{,c
userManager.listUser(page)即可得到一个Page对象和结果集对象 WLg6-@kxXs
jKY Aid{-
的综合体,而传入的参数page对象则可以由前台传入,如果用 $Uv<LVd(
eONeWY9
webwork,甚至可以直接在配置文件中指定。 .FfwY 'V
N7RG5?
下面给出一个webwork调用示例: pfJVE
java代码: N"q+UCRC
CSd9\V
/xX,
/*Created on 2005-6-17*/ a"v"n$
package com.adt.action.user; r|
6S
ihpz}g
import java.util.List; >#"jfjDuR
u8{@PlS
import org.apache.commons.logging.Log; W<cW;mO
import org.apache.commons.logging.LogFactory; ^C,/T2>
import org.flyware.util.page.Page; 7gZVg@
dw{#||
import com.adt.bo.Result; ,q'gG`M
N
import com.adt.service.UserService; Pq[0vZ_}dN
import com.opensymphony.xwork.Action; n]6}yJJo
6N)<
o ;U
/** clR?< LO
* @author Joa V1CSXY\2
*/ &<fRej]v
publicclass ListUser implementsAction{ \gJapx(
PJSDY1T
privatestaticfinal Log logger = LogFactory.getLog \@
WsF$
*`S)@'@:(
(ListUser.class); x[.z"$T@
}jyS\drJ
private UserService userService; @kCD.
2EqsfU*
I
private Page page; {'=Nb
5F
5 vu_D^Q
privateList users; ,XBV }y
cc2 oFn
/* SG+i\yu$h0
* (non-Javadoc) |Ad6~E+aL-
* e8P!/x-y
* @see com.opensymphony.xwork.Action#execute() t7*H8
*/ ]` &[Se d
publicString execute()throwsException{ v,!Y=8~9
Result result = userService.listUser(page); g.`t!6Hc
page = result.getPage(); eN2k8=
users = result.getContent(); 3>@qQ_8%~
return SUCCESS; >m_p\$_
} [WO%rO^p
VATXsD
/** &"H<+>`
* @return Returns the page. $E9daUt8"J
*/ @cTZ`bg
public Page getPage(){ beHCEwh
return page; GHgEbiY:
} n%MYX'0
]RrP !|^
/** /YugQ.>| l
* @return Returns the users. B,m$ur#$
*/ @#ho(_U8
publicList getUsers(){ A2O_pbQti
return users; Lugk`NUvF
} C+#;L+$Gi
aa YQ<
/** 1KIq$lG{ E
* @param page A@
* The page to set. cT=wJ
*/ cmGj0YUQ1
publicvoid setPage(Page page){ nXeK,C
this.page = page; j+B5m:ExfI
} I.\f0I'.
KutgW#+40
/** ?D^,K`wY=B
* @param users RnBmy^l"
* The users to set. oQjB&0k4
*/ Nj@?}`C 4
publicvoid setUsers(List users){ w KMk|y>
this.users = users; <iprPk
} Q}f}Jf3P
://#
%SE
/** n\ ',F
* @param userService >\oJ&gdc
* The userService to set. =UKR<@QrK
*/ {LJ6't 8y:
publicvoid setUserService(UserService userService){ =5=Vm[
this.userService = userService; jnKM6%z
} 5NvyK[w]
} (yTz^o$t|
*=0r>]
M^JZ]W(
\/4%[Q2QDm
sriq(A
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, /,@v"mE7c!
@)'@LF1Z
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 ;@Hi*d[
>/`cmNmb
么只需要: /uz5V/i0
java代码: ?*mbce[
%iS]+Sa.K
H|:)K^o
<?xml version="1.0"?> ?G>TaTiK#
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork [
EID27P
jhbH6=f4]^
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 95 .'t}
=
hX-jP
1.0.dtd"> hYv 6-5_
ee0>B86tE
<xwork> p}zk&`
$H@)hY8wA
<package name="user" extends="webwork- <07W&`Dw
`0XbV A
interceptors"> & c9Fw:f;
Wk6&TrWlY
<!-- The default interceptor stack name WJ8vHPSM
.'mC3E+$
--> &r5%WRzpYT
<default-interceptor-ref 3v>,c>b([
BOQV X&g%
name="myDefaultWebStack"/> )hJjVitG
[K@!JY
<action name="listUser" G/3lX^Z>
]JPPL4wAT
class="com.adt.action.user.ListUser"> lbU+a$
<param mf_'|
WDs
+pViHOJu&V
name="page.everyPage">10</param> (C|V-}/*m
<result 0Ilvr]1a4
xWb?i6)z&
name="success">/user/user_list.jsp</result> 7:q-NzE\6
</action> \0T*msYQ
}e=GvWGa
</package>
9QZ wUQ
(Ha}xwA~(
</xwork> WzbN=&
C]h
o?
"@9O?
kGiw?~t=%
2#M:JgWV
rPvX8*)tV
g}r5ohqC#
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 J$*["y`+
[m[~A|S
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 }(}vlL
pytfsVM
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 1V$B^/ _
Z@O
e}\.$
]!o,S{a&
Pm;*Jv%
TEZqAR]G
我写的一个用于分页的类,用了泛型了,hoho W%Q>< 'c
r9*H-V$
java代码: [z@RgDXv
H1i4_T
A_U0HVx_
package com.intokr.util; zb,`K*Z{
}mZ*f y0t
import java.util.List; J
uKaRR~
3-%~{(T/
/** m?G+#k;K
* 用于分页的类<br> pvxqeC9`
* 可以用于传递查询的结果也可以用于传送查询的参数<br> cty#@?"e
* 8^i,M^f^{
* @version 0.01 c2:kZxT
* @author cheng 4>`w9
*/ qZ1PC>
public class Paginator<E> { Q 5TyS8
privateint count = 0; // 总记录数 8so}^2hTlT
privateint p = 1; // 页编号 <_uv!N
privateint num = 20; // 每页的记录数 gipRVd*TA
privateList<E> results = null; // 结果 m]pvJJ@
A1T;9`E
/** Kx!|4ya,
* 结果总数 vjS7nR"T
*/ 3_-m>J**
publicint getCount(){ D"5~-9<
return count; -bQvJ`iF
} (XWs4R.mkb
-q|M=6gOs
publicvoid setCount(int count){ ;%9ZL[-
this.count = count; @},k\Is
} x9s`H)
9j9?;3;
/** PmTd+Gj$
* 本结果所在的页码,从1开始 X)5O@"4 ?
* ,aL"Wy(
* @return Returns the pageNo. CcETS}Q0C
*/ +O6@)?pI
publicint getP(){ k Er7,c
return p; "E#%x{d
} .<hv&t
NYRNop( N#
/** =2'^:4Z
* if(p<=0) p=1 Rvo<ISp
* |V]E8Qt
* @param p > xw+2<
*/ 2Ta F7Jn
publicvoid setP(int p){ V4D&&0&n
if(p <= 0) ktb.fhO
p = 1; #k, kpL<a
this.p = p; hG)lVo!L4j
} euK!JZ
Kz;VAH
/** y0^FTSQ|
* 每页记录数量 :#;?dMkTY
*/ `dhK$jYD
publicint getNum(){ un=)k;oh
return num; ZO^+KE"
} p6*D^-
I&0yUhn
/** yE>DQ *
* if(num<1) num=1 I+SL0
*/ g!UM8I-$
publicvoid setNum(int num){ @hv]
[(<
if(num < 1) 52,a5TVG
num = 1; 5+J/Qm8{bb
this.num = num; 7[\B{N9&W
} ^4:= b
;RI,zQ
/** s+11) ~
* 获得总页数 :OM>z4mQ
*/ 3z<t#
publicint getPageNum(){ XDF",N)
return(count - 1) / num + 1; gg9W7%t/
} n:+MNr
tz{]H9
/** }e$);A|
* 获得本页的开始编号,为 (p-1)*num+1 $) $sApB
*/ I{$|Ed1
publicint getStart(){ w;"'l]W
return(p - 1) * num + 1; xXtDGP
} w pvaTHo
(g\'Zw5bk
/**
;L7<mU
* @return Returns the results. 01$SvLn:
*/ h)rHf3:
publicList<E> getResults(){ C-7.Sa
return results; lF<(yF5
} ^]kDYhe*Y
|v+b?@
public void setResults(List<E> results){ 0=04:.%D
this.results = results; %K%z<R8
} O_033&
k"6^gup(U
public String toString(){ "6ZatRUd
StringBuilder buff = new StringBuilder cg4,PI%hz
2yNlQP8%
(); 3yQ(,k #
buff.append("{"); S=o/n4@}
buff.append("count:").append(count); @`3)?J[w
buff.append(",p:").append(p); ;Wr$hDt^
buff.append(",nump:").append(num); ,70|I{,Km
buff.append(",results:").append @!-= :<h
opBvx>S
(results); +XQ6KG&
buff.append("}"); 3wK)vW
return buff.toString(); J&5|'yVX
} C][`Dk\D{
jE{z4en
} 5d)G30
*I~F7Z]|
u5lj+?