Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 61Z#;2]
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Ywj=6 +;
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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 l7 +#gPA
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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 ZZkxEq+D
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分页支持类: [0_JS 2KE
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java代码: a@|/D\C
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package com.javaeye.common.util; L<kIzB !
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import java.util.List; T;cyU9
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publicclass PaginationSupport { g/)$-Z)Nu
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publicfinalstaticint PAGESIZE = 30; R&w2y$
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privateint pageSize = PAGESIZE; /jR]sC)xs
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privateList items; 2v!ucd}
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privateint totalCount; 4=j,:q
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privateint[] indexes = newint[0]; )V!9/d
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privateint startIndex = 0; '~dE0ohWb
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public PaginationSupport(List items, int MA:2]l3e
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totalCount){ 0-)D`s%
setPageSize(PAGESIZE); $ae*3L>5M
setTotalCount(totalCount); b.qp&2 A
setItems(items); nI1DLVt
setStartIndex(0); _3q%
} h[5<S&
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public PaginationSupport(List items, int "3!!G=s P
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totalCount, int startIndex){ VZOf| o
setPageSize(PAGESIZE); R3MbTg
setTotalCount(totalCount); o8!gV/oy
setItems(items); QN %w\JXS
setStartIndex(startIndex); ?/mk FDN
} *. H1m{V
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public PaginationSupport(List items, int O1/U3/2/d
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totalCount, int pageSize, int startIndex){ 3xhv~be
setPageSize(pageSize); ~R`Rj*Q2Y
setTotalCount(totalCount); ;WQ@dC
setItems(items); "J0,SFu:
setStartIndex(startIndex); ; Q-f6)+&
} fIrl?X']
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publicList getItems(){ gTI!b
return items; l2DhFt$!=
} T [w]w
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publicvoid setItems(List items){ %-~W|Y
this.items = items; +39Vxe:Oy
} uV]4C^k;`[
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publicint getPageSize(){ >U~B"'!xV
return pageSize; _":yUa0D
} Ua.7_Em
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publicvoid setPageSize(int pageSize){ u-W6 hZ$
this.pageSize = pageSize; :Zy7h7P,lT
} -+1it
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publicint getTotalCount(){ S~"1q 0
return totalCount; 32_{nLV$[
} \`w!v,aM$
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publicvoid setTotalCount(int totalCount){ Q AJX7
if(totalCount > 0){ v1hrRf2<
this.totalCount = totalCount; 39;Z+s";
int count = totalCount / =*q|568
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pageSize; 4\HB rd#P
if(totalCount % pageSize > 0) h&7]Bp
count++; [3a-1,
indexes = newint[count]; o0- 7# 2
for(int i = 0; i < count; i++){ AL.zF\?
indexes = pageSize * /o=V
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i; =d/\8\4
} (wmMHo|
}else{ X\SZ Q[gN
this.totalCount = 0; CPq{M.B
} <!.'"*2
} -b>"2B?
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publicint[] getIndexes(){ I)~&6@Jn
return indexes; 15Vb`Vf`N
} #C?T
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publicvoid setIndexes(int[] indexes){ [Rh[Z #6
this.indexes = indexes; W~GbB:-
} 8?S32Gdu
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publicint getStartIndex(){ V:h-K`~/
return startIndex; R9SJ;TsE
} '3Ir(]Wfd
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publicvoid setStartIndex(int startIndex){ 7<Fp3N 3
if(totalCount <= 0) pv2_A
this.startIndex = 0; .xT8@]
elseif(startIndex >= totalCount) s)$N&0\
this.startIndex = indexes -Iz&/u*}f
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[indexes.length - 1]; 7%Zl^c>q
elseif(startIndex < 0) 4!Ez#\
this.startIndex = 0; wiWpzJz
else{ s8| =1{
this.startIndex = indexes so|5HR|
F_ ~L&jHP
[startIndex / pageSize]; =z'w-ARy
} DSY:aD!
} U^4
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publicint getNextIndex(){ ./@!k[
int nextIndex = getStartIndex() + #5GIO
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pageSize; >_QC_UX>4i
if(nextIndex >= totalCount) qu[ ~#
return getStartIndex(); Gx?p,Fj
else q/xMM`{
return nextIndex; RQI? \?o
} !|`G<WD
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publicint getPreviousIndex(){ ReOp,A/y
int previousIndex = getStartIndex() - 2=X 2M
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pageSize; 8P r H"pI
if(previousIndex < 0) =whZ?,u1
return0; 0uzm@'^
else Ec| Gom?
return previousIndex; q10gKVJum
} W=M`Bkw{
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} %sb)U~gP
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抽象业务类 &Zl$7
java代码: $: "r$7
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/** I*R[8|
* Created on 2005-7-12 _aVrQ@9
*/ OaU-4
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package com.javaeye.common.business; mxtLcG4G
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import java.io.Serializable; V6"<lK8"
import java.util.List;
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import org.hibernate.Criteria; fk)ts,p?
import org.hibernate.HibernateException; tS,nO:+x
import org.hibernate.Session; |du@iA]dP
import org.hibernate.criterion.DetachedCriteria; *,hS-
import org.hibernate.criterion.Projections; t4pc2b
import _ngyai1
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org.springframework.orm.hibernate3.HibernateCallback; !YL|R[nDH|
import ([zt}uf
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org.springframework.orm.hibernate3.support.HibernateDaoS \B"5 Kp<
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upport; oK&LYlU
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import com.javaeye.common.util.PaginationSupport; ^,')1r,
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public abstract class AbstractManager extends
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HibernateDaoSupport { 5Z}]d@
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privateboolean cacheQueries = false; \|nF55W [
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privateString queryCacheRegion; 'M185wDdAl
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publicvoid setCacheQueries(boolean 6lO]V=+
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cacheQueries){ qEr2Y/:i"
this.cacheQueries = cacheQueries; r
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} q}e"E
cr
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publicvoid setQueryCacheRegion(String <qN0Q7
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queryCacheRegion){ 8
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this.queryCacheRegion = sfi.zuG
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queryCacheRegion; xy$73K6
} =8$//$
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publicvoid save(finalObject entity){ q%TWtQS
getHibernateTemplate().save(entity); &Yi)|TU3'R
} qLBXyQ;U
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publicvoid persist(finalObject entity){ 9{|JmgO!
getHibernateTemplate().save(entity); G\G TS}u[
} >k,|N4(
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publicvoid update(finalObject entity){ l CHaRR7
getHibernateTemplate().update(entity); /PG+ s6
} =3OK3|
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publicvoid delete(finalObject entity){ ;LE4U OK
getHibernateTemplate().delete(entity); }r$&"wYM
} q65KxOf`
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publicObject load(finalClass entity, r=P)iE:
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finalSerializable id){ r2}u\U4>
return getHibernateTemplate().load =; Gw=m(
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(entity, id); Aifc0P-H
} \Km!#:
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publicObject get(finalClass entity, 3ny>5A!;2
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finalSerializable id){ n 1MZHa,
return getHibernateTemplate().get 1S9(Zn[2,
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(entity, id); [2?|BUtD[
} XlUM ~(7+v
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publicList findAll(finalClass entity){ O=UXe]D
return getHibernateTemplate().find("from ehk5U,d
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" + entity.getName()); xF:
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} &<6E*qM
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publicList findByNamedQuery(finalString vdw5T&Q{{C
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namedQuery){ tJ[yx_mf
return getHibernateTemplate YXI_ '
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().findByNamedQuery(namedQuery); M#X8Rs1`
} 51j5AbFQ"
q/U(j&8W{
publicList findByNamedQuery(finalString query, HA&7
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finalObject parameter){ rx2?y3pv
return getHibernateTemplate #\s*>Z
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().findByNamedQuery(query, parameter); c'cK+32
}
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publicList findByNamedQuery(finalString query, CXt9 5O?
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finalObject[] parameters){ `)V1GR2
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return getHibernateTemplate Y~\71QE>
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().findByNamedQuery(query, parameters); yUV0{A-q{0
} .nN=M>#/
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publicList find(finalString query){ eewhT^
return getHibernateTemplate().find np2oXg%
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(query); ,/0Q($oz
} zVN/|[KP4
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publicList find(finalString query, finalObject PdiP5S }/
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parameter){ EdGA#i3
return getHibernateTemplate().find ?bFP'.
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(query, parameter); BGM5pc (ei
} k=;>*:D%
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public PaginationSupport findPageByCriteria :"m~tU3&
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(final DetachedCriteria detachedCriteria){ FY;\1bt<<
return findPageByCriteria #a1zk\R3
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?%RAX CK
} G!]%xFwYa
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public PaginationSupport findPageByCriteria y?=W
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(final DetachedCriteria detachedCriteria, finalint U'(Exr[
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startIndex){ 5mzOr4*0
return findPageByCriteria &UzeNL"]
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(detachedCriteria, PaginationSupport.PAGESIZE, WFWQ;U{|
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startIndex); Y~I$goT
} GMk\
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public PaginationSupport findPageByCriteria ed3d 6/%HR
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(final DetachedCriteria detachedCriteria, finalint LV4\zd6
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pageSize, mCM7FFl I
finalint startIndex){ b1+6I_u.
return(PaginationSupport) H~Z$ pk%
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getHibernateTemplate().execute(new HibernateCallback(){ v[$-)vs*ag
publicObject doInHibernate C]@v60I
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(Session session)throws HibernateException { 3[q&%Z.
Criteria criteria = 0cYd6u@
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detachedCriteria.getExecutableCriteria(session); ~kDR9s7
int totalCount = '8%pEl^
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((Integer) criteria.setProjection(Projections.rowCount 2Y~UeJ_\Lq
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()).uniqueResult()).intValue(); TcB^Sctf
criteria.setProjection -Iq
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(null); _(J;!,
List items = T,'{0q
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criteria.setFirstResult(startIndex).setMaxResults 1zo0/<dk
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(pageSize).list(); ^3>Qf
PaginationSupport ps = MHF31/g\
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new PaginationSupport(items, totalCount, pageSize, M.DU^-7
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startIndex); cL+--$L
return ps; Mn)>G36(
} Oup5LH!sW
}, true); p#14
} bxxazsj^
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public List findAllByCriteria(final r'TxYM-R
[_$r- FA
DetachedCriteria detachedCriteria){ 3o).8b_3g
return(List) getHibernateTemplate Vgh;w-a
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().execute(new HibernateCallback(){ |AosZeO_
publicObject doInHibernate ~Onj|w7
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(Session session)throws HibernateException { -|1H-[Y(
Criteria criteria = w@K4u{|
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detachedCriteria.getExecutableCriteria(session); ;HKb
return criteria.list(); 4blw9x N
} It5U=PU
}, true); M lv
} KOQiX?'
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public int getCountByCriteria(final {c
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DetachedCriteria detachedCriteria){ "7w~0?}
Integer count = (Integer) .,-,@ZK
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getHibernateTemplate().execute(new HibernateCallback(){ ,5Vc
publicObject doInHibernate \IL;}D{
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(Session session)throws HibernateException { ujlIWQU2mo
Criteria criteria = $`KddW0_
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detachedCriteria.getExecutableCriteria(session); %1Ex{H hb
return L&gC
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criteria.setProjection(Projections.rowCount `&3hfiI}
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()).uniqueResult(); |E&
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} g431+O0K1
}, true); \tpJ
return count.intValue(); PZT]H?
} rP5&&Hso
}
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用户在web层构造查询条件detachedCriteria,和可选的 (31ia"i%
c
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 V6c>1nZ
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PaginationSupport的实例ps。 9s#Q[\B!
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ps.getItems()得到已分页好的结果集 S!LLC{
ps.getIndexes()得到分页索引的数组 U{ZE|b.?b
ps.getTotalCount()得到总结果数 r8R]0\
ps.getStartIndex()当前分页索引 YmBo/I M
ps.getNextIndex()下一页索引 ]+U:8*
ps.getPreviousIndex()上一页索引 U-U^N7
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;s^br17z~
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 CMcS4X9/}
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一下代码重构了。 [!g$|
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我把原本我的做法也提供出来供大家讨论吧: z:
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首先,为了实现分页查询,我封装了一个Page类: o@6hlLr
java代码: +#B4Z'nT
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/*Created on 2005-4-14*/ *mvDh9v
package org.flyware.util.page; ;0Vyim)S]
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/** k=nN#SMn
* @author Joa *y}<7R
* $]
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*/ p)x*uqSd
publicclass Page { #mK/xbW
:jKiHeBQu?
/** imply if the page has previous page */ F6L}n-p5
privateboolean hasPrePage; -T,/S^
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/** imply if the page has next page */ LR(Q.x
privateboolean hasNextPage; TKwMgC}<[
a?d)lnk
/** the number of every page */ $i|c6&
privateint everyPage; O<*l"fw3
b`9J1p.;
/** the total page number */ ym]12PAU5
privateint totalPage; 5PcN$r"P
KTmduf7DL
/** the number of current page */ Ar;uq7c,G
privateint currentPage; q2$-U&
]_hrYjX;
/** the begin index of the records by the current 9s.x%m,
Mnv2tnU]
query */ w !5@PJ)~U
privateint beginIndex; D*nNu]|j
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7A@iu*t
/** The default constructor */ b|rMmx8vA
public Page(){ \{GBaMwG~
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} g?9IS,Gp
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/** construct the page by everyPage QE#Ar8tU
* @param everyPage FX
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* */ 2 &(w\#'
public Page(int everyPage){ 8V08>M
this.everyPage = everyPage; 8Qo~zO
} yF _@^V
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/** The whole constructor */ 3IlflXb
public Page(boolean hasPrePage, boolean hasNextPage, rw|;?a0
=JR6-A1>
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int everyPage, int totalPage, NCXr$ES{
int currentPage, int beginIndex){ 2w7PwNb*32
this.hasPrePage = hasPrePage; _MI8P/
this.hasNextPage = hasNextPage; 46(=*iT&V
this.everyPage = everyPage; 4Y>J,c
this.totalPage = totalPage; _Yms]QEZ
this.currentPage = currentPage; }+m")=1{
this.beginIndex = beginIndex; Sc?UjEs
} O:I"<w 9_1
4g%BCGsys
/** kp$w)%2JW
* @return (b*PDhl`+
* Returns the beginIndex. ,$,c<M
*/ KJs/4oR;
publicint getBeginIndex(){ q!O B?03n
return beginIndex; ]zt77'J
} jG E=7
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/** %x]8^vze
* @param beginIndex h{5K9$9=
* The beginIndex to set. h,!#YG@>
*/ f6*6 *=
publicvoid setBeginIndex(int beginIndex){ G9|w o)N
this.beginIndex = beginIndex; .^F(&c*['
} ?RMOy$L
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/** C 7a$>#%
* @return
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* Returns the currentPage. f)b+>!
*/ Dus [N<
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publicint getCurrentPage(){ A@?Rj
return currentPage; ?b,x;hIO
} jfOqE*frl!
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/** Rt6(y #dF
* @param currentPage \I[f@D-J
* The currentPage to set. Osk'zFiL<
*/ WxrGoo^
publicvoid setCurrentPage(int currentPage){ g2|qGfl{C
this.currentPage = currentPage; kgl7l?|O
} &|
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6 o!*bWh
/** ' ~F
* @return q\r@x-&g+
* Returns the everyPage. qx;8Hq(E[
*/ DDwj[' R
publicint getEveryPage(){
A|90Ps
return everyPage; :p|wo"=@Ge
} y+"6Y14
*i)3q+%.
/** Af`qe+0E
* @param everyPage 6`JY:~V"
* The everyPage to set. Ob~7r*q
*/ V:Lq>rs#
publicvoid setEveryPage(int everyPage){ 8=T[Y`;x
this.everyPage = everyPage;
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} |RS(QU<QE
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/** S!r,p};
* @return e%wzcn
* Returns the hasNextPage. {pR4+g
*/ ~ 7^#.
publicboolean getHasNextPage(){ xaw)iC[gI{
return hasNextPage; |Vj@;+/j
} EG&97lb
)/{zTg8$?/
/** =U- w!uW
* @param hasNextPage zcrM3`Zh
* The hasNextPage to set. %0MvCm
*/ G oHdhne3
publicvoid setHasNextPage(boolean hasNextPage){ +;|" #
this.hasNextPage = hasNextPage; |vUjoa'.7E
} v&]k8Hc-
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/** wa f)S=
* @return ":meys6t#
* Returns the hasPrePage. Gkr?M^@K
*/ }9FAM@x1K&
publicboolean getHasPrePage(){ &9ZrZ"]
return hasPrePage; y~'h/tjM@=
} \YZ7
TilCP"(6D
/** 5?=haGn
* @param hasPrePage a^xt9o`
* The hasPrePage to set. y~Ts9AE
*/ "R5! VV
publicvoid setHasPrePage(boolean hasPrePage){ >K@Y8J+e#
this.hasPrePage = hasPrePage; lB<
kf1[
} 1.S?(1e"
E/:mO~1< c
/** M!D&a)\
* @return Returns the totalPage. U-6pia/o
* xro%AM
*/ }1}L&M@
publicint getTotalPage(){ iU1yJ=
return totalPage; /9o
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} cqSo%a2
NSV;R~"
/** gZ W(z
* @param totalPage 7E]qP
5
* The totalPage to set. \96aHOk<
*/ Py^fWQ5I~%
publicvoid setTotalPage(int totalPage){ +v{g'
this.totalPage = totalPage; |J^}BXW'^)
} r
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} vjz 'y[D
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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 ur@"wcl"V
U'oFW@Y;h
个PageUtil,负责对Page对象进行构造: 8ZN"-]*
java代码: oQL$X3S
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/*Created on 2005-4-14*/ (
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package org.flyware.util.page; kes
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{4^NZTjd@
import org.apache.commons.logging.Log; , #nYH D
import org.apache.commons.logging.LogFactory; F~Sw-b kSf
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/** 3IyNnm=u
* @author Joa K*sav?c
* ZFFKv
*/ O =gv2e
publicclass PageUtil { ]*v[6 +
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privatestaticfinal Log logger = LogFactory.getLog Y=$PsDh!
DOB#PI[/
(PageUtil.class); uN*Ynf(:-
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/** $_Kcm"oj
* Use the origin page to create a new page Yj{-|2YzL
* @param page t#N@0kIX.
* @param totalRecords UpFm3gKF
* @return I(Gl8F\c~
*/ Y9r##r+
publicstatic Page createPage(Page page, int H[ o > "@4
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totalRecords){ nmWo:ox4;(
return createPage(page.getEveryPage(), g/(3D
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page.getCurrentPage(), totalRecords); Z!foD^&R
} #gc v])to
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/** k}hTSL
* the basic page utils not including exception MJugno
7wz9x8 \t
handler S3N+9*iK
* @param everyPage A81'ca/
* @param currentPage wmDO^}>ZP
* @param totalRecords 59#o+qo4
* @return page M"s+k
*/ >XJUj4B|X
publicstatic Page createPage(int everyPage, int BIY"{"hJ
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currentPage, int totalRecords){ pQCocy
everyPage = getEveryPage(everyPage); PR3&LI;B*
currentPage = getCurrentPage(currentPage); =OamN7V=
int beginIndex = getBeginIndex(everyPage, &B?*|M`)k
F&u)wI'
currentPage); wB+X@AA
int totalPage = getTotalPage(everyPage, ;2}wrX
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totalRecords); l>*L
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boolean hasNextPage = hasNextPage(currentPage, ^Rh`XE
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totalPage); A/sM
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boolean hasPrePage = hasPrePage(currentPage); aL^
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returnnew Page(hasPrePage, hasNextPage, (Tv~$\=
everyPage, totalPage, @bF4'M
currentPage, -LU%z'
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beginIndex); &2sfu0K
} ^E&WgXlb
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privatestaticint getEveryPage(int everyPage){ [79iC$8B|
return everyPage == 0 ? 10 : everyPage; ;iO5
8S3
} k*K.ZS688
]XjL""EbC
privatestaticint getCurrentPage(int currentPage){ +lw8YH
return currentPage == 0 ? 1 : currentPage; 2?nEHIUT
} cnz+%Y N
'1"vwXJ"
privatestaticint getBeginIndex(int everyPage, int v(P5)R,
XsGc!o
currentPage){ C;I:?4
return(currentPage - 1) * everyPage; ^tY
_ q
} Y2aN<>f
61Wh %8-
privatestaticint getTotalPage(int everyPage, int H(tT8Q5i
1O2jvt7M
totalRecords){ Sb.%B^O
int totalPage = 0; 0b}.!k9
m[qW)N:w
if(totalRecords % everyPage == 0) x5R|,bY
totalPage = totalRecords / everyPage; _sK{qQxvM=
else $1Qcz,4B|
totalPage = totalRecords / everyPage + 1 ; +?v2MsF']
*nSKIDw
return totalPage; %[x
PyqX
} qFXx/FZ
8EY]<#PN
privatestaticboolean hasPrePage(int currentPage){ >Xi/ p$$7u
return currentPage == 1 ? false : true; w >w zV=R
} ?izl#?
p&2oe\j$,
privatestaticboolean hasNextPage(int currentPage, p :zRgwcn
#|/+znJm
int totalPage){ }=p+X:k=
return currentPage == totalPage || totalPage == >e!Y 63`
.'bhRQY
0 ? false : true; J1Run0
} @_0tq {
NH<~BC]I
r"!xI
} $]gflAe2
Gq-~zmg
(,D:6(R7t
Xi0fX$-,
g(dReC
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。 LZDJ\"a-
INY?@in
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 rE%HNPO
h_5CWQSi
做法如下: O!P7Wu
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 q!{>Nlk
6&o?#l;|
的信息,和一个结果集List: *p0Kw>
java代码: 1s.>_
Id=V\'$o
0ax;Q[z2
/*Created on 2005-6-13*/ ?\$6"c<G
package com.adt.bo; PR7B
Cxm
sh*/wM
import java.util.List; kS4YxtvB
40G'3HOp
import org.flyware.util.page.Page; zEt!Pug
>D%
/** ! ~tf0aY
* @author Joa Q5HSik4
*/ \_x~lRqJJ
publicclass Result { 54#P
'Pxq>Os
private Page page; CU:HTz=
g3f;JB
private List content; QUDpAW
NAOCQDk{
/** 7^C&2k5G
* The default constructor iN_P25Z<r
*/ gYBMi)`RT
public Result(){ v.hQ9#:
super(); $HCgawQ
} *U-:2uf
T+oOlug
/** B!U;a=ia
* The constructor using fields 5A+@xhRf
* *T~b
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* @param page DFvGc`O4
* @param content "^)GnK +-
*/ b[J0+l\!"
public Result(Page page, List content){ /=g/{&3[a>
this.page = page; Yl=-j
this.content = content; >[;L.
} 8erG](
3taGb>15
/** [Sj"gLj
* @return Returns the content. `g<0FQA
*/ frc9
publicList getContent(){ v3{%U1>}v
return content; z[@i=avPG
} m\70&%v
a#lytp
/** rBOH9L
* @return Returns the page. Z5
7.+z<
*/ YFDOp*
public Page getPage(){ DTa!vg
return page; <s%Ft
} qWf[X'
USaa#s4'
/** ) O&zb_{n
* @param content q[9N4nj$<
* The content to set. r&IDTS#
*/ DP;:%L}
public void setContent(List content){ P-<1vfThH
this.content = content;
n(|rs
} Ow(aRWUZD_
=zu;npM
/** 5A<}*T
* @param page ydA@@C\&
* The page to set. p{:y?0pGN
*/ CM%;/[WBxy
publicvoid setPage(Page page){ ?J-\}X
this.page = page; yL),G*[p\}
} >TiEYMW
} /8!n7a7
/;{L~f=et)
jT!?lqr(Rb
c,O;B_}M]
+TX4,"
2. 编写业务逻辑接口,并实现它(UserManager, pjl>ZoOM
e7b MK<:r
UserManagerImpl) *Mb'y d/|
java代码: 'oH3|
eoXbZ
Bl^BtE?-b
/*Created on 2005-7-15*/ aqWlX0+
package com.adt.service; Djdd|Z+*{
v??$z#1F3
import net.sf.hibernate.HibernateException; "Q:h[) a
z`.<dNg
import org.flyware.util.page.Page; '$eJATtC
{> 8?6m-
import com.adt.bo.Result; }!?RB v'W
Gs,e8ri!
/** ;)wk^W
* @author Joa e ;^}@X
*/ GgnR*DVP$
publicinterface UserManager { ^do6?e`?-
QPh3(K1w^
public Result listUser(Page page)throws UvM4-M%2JN
\WbQS#Z9
HibernateException; DycXJ3eQ
HVhP |+
} n>7aZ1Qa
H?!DcUg CC
CJ7S5
qVI0?B
x
=9W\;xE S
java代码: rV4K@)~
sH_,P
3~V.
/*Created on 2005-7-15*/ Lis>Qr
package com.adt.service.impl; F_m'
9KX4E
$d!Vx m
import java.util.List; 0
x' d^
(xoYYO
import net.sf.hibernate.HibernateException; uubIL+
17,mqXX>
import org.flyware.util.page.Page; +GL$[ 5G
import org.flyware.util.page.PageUtil; SWY
RgL>0s
import com.adt.bo.Result; +
d 3
import com.adt.dao.UserDAO; pT3icy!A=
import com.adt.exception.ObjectNotFoundException; $45.*>,
import com.adt.service.UserManager; Sk1t~
f8aY6o"i
/** f$n5$hJlQ
* @author Joa Pqw<nyC.
*/ ^6R(K'E}
publicclass UserManagerImpl implements UserManager { U*E)y7MY
\G7F/$g
private UserDAO userDAO; =6O*AJ
-ucgET`
/** 8D,*_p
* @param userDAO The userDAO to set. D4{KU%Xp&
*/ QxGcRlpLK
publicvoid setUserDAO(UserDAO userDAO){ %[s%H)e)
this.userDAO = userDAO; ?FjnG_Uz`D
} Wz"H.hf
Kop(+]Q&n
/* (non-Javadoc) h3&|yS|
* @see com.adt.service.UserManager#listUser Crg'AB?
?w'86^_z
(org.flyware.util.page.Page) Z<^!N)
*/ ,W|-?b?
public Result listUser(Page page)throws 02trjp.f
B>m*!n:l
HibernateException, ObjectNotFoundException { 9xhc:@B1J
int totalRecords = userDAO.getUserCount(); V>,=%r4f
if(totalRecords == 0) 'P" i9j
throw new ObjectNotFoundException 9=3DYCk/
;b~\[
("userNotExist"); (_<,Oj#*S
page = PageUtil.createPage(page, totalRecords); t89Tt @cf
List users = userDAO.getUserByPage(page); a!-J=\>9
returnnew Result(page, users); c.b| RM0;
} **kix
>:> W=
} FKz5,PeL
wT6zeEV~*
<F;+A{M)
#vxq|$e
m%apGp'=1
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 KR%WBvv
Qni`k)4
询,接下来编写UserDAO的代码: `>`b;A4
3. UserDAO 和 UserDAOImpl: |:JT+a1
java代码: Xa.8-a"hz
{,+c
Ez0zk9
/*Created on 2005-7-15*/ KXK5\#+L
package com.adt.dao; dpscgW{M
)7NI5x^$
import java.util.List; $--+M
D29Q
5B4/2q=
import org.flyware.util.page.Page; r{9fm,
X!^|Tass
import net.sf.hibernate.HibernateException; 9J?s:"j
-~lq <M
/** xk%
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* @author Joa 25-h5$s
*/ megTp
publicinterface UserDAO extends BaseDAO { AH5;6Q
htR.p7&Tn
publicList getUserByName(String name)throws p/VVb%
2M'dTXz
HibernateException; $*iovam>^]
]VLseF
publicint getUserCount()throws HibernateException; 3oMHy5
ZIc.MNq
publicList getUserByPage(Page page)throws j]<K%lwp
B 5|\<CF
HibernateException; }UB@FRPF
S#y[_C?H
} ^PezV5(
4fC:8\A
?SElJ?Z
`HkNO@N[
3u$1W@T(
java代码: CssE8p>"F
[i ~qVn2vT
?zm]KxIC
/*Created on 2005-7-15*/ lYJSg70P
package com.adt.dao.impl; oq+w2yR
3cL
iZ%6^
import java.util.List; adX"Yg!`{c
!=,Y=5M,
import org.flyware.util.page.Page; -|uoxj>
`>)Ge](oN
import net.sf.hibernate.HibernateException; R=LiB+p
import net.sf.hibernate.Query; 35e{{Gn)v
vBl:&99[/
import com.adt.dao.UserDAO; pF8 #H~
\"nut7";2
/** o?hr>b
* @author Joa p ZTrh&I]
*/ >a<1J(c
public class UserDAOImpl extends BaseDAOHibernateImpl +|,4g_(j
XgHJ Oqt
implements UserDAO { -"dt3$ju
e@ZM&iR
/* (non-Javadoc) m\0_1 #(
* @see com.adt.dao.UserDAO#getUserByName /~ {`!30
Rt+ -ud{O
(java.lang.String) > ]^'h
*/ uI/
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publicList getUserByName(String name)throws G#GZt\)F
%NxQb'
HibernateException { \>-
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String querySentence = "FROM user in class }QE*-GVv]
u/u(Z&
com.adt.po.User WHERE user.name=:name"; c Pf_B=
Query query = getSession().createQuery #6<1
=I'j
OpEH4X.Z
(querySentence); F. SB_S<'
query.setParameter("name", name); j/d}B_2
return query.list(); y]fI7nu&
} =oq8SL?bJ*
lt&(S)
/* (non-Javadoc) ggx_h
* @see com.adt.dao.UserDAO#getUserCount() daI_@k Y"
*/ Z%qtAPd
publicint getUserCount()throws HibernateException { 3>aEP5
int count = 0; bPU
i44P
String querySentence = "SELECT count(*) FROM
r_#dh
lFyDH{!
user in class com.adt.po.User"; w&aZ 97{
Query query = getSession().createQuery
8'8`xu$
bH e'
U>
(querySentence); nm,LKS7
count = ((Integer)query.iterate().next F^NK"<tW
<]M.K3>
()).intValue(); Wjw,LwB
return count; aIV
/ c
} - |g"q|
'%QCNO/
/* (non-Javadoc) vyIH<@@p7
* @see com.adt.dao.UserDAO#getUserByPage E>|X'I?r^
*(F`NJ 3
(org.flyware.util.page.Page) WYUDD_m
*/ mOsp~|d
publicList getUserByPage(Page page)throws =Nxkr0])!
WQ.0} n}d
HibernateException { 1*TbgxS~W
String querySentence = "FROM user in class WK>|IgK
^Fco'nlM
com.adt.po.User";
>Q\Kc=Q|
Query query = getSession().createQuery {7OHEArv
c0gVW~I1
(querySentence); ;mG*Rad
query.setFirstResult(page.getBeginIndex()) `.W2t5Y
.setMaxResults(page.getEveryPage()); `x`[hJ?i
return query.list(); DVL-qt\;n
} E5bVCAz
){5Nod{}a
} xV)[C )6
bx8](cT_
4VwF\
&vpKBR^
\g39>;iR
至此,一个完整的分页程序完成。前台的只需要调用 USz~l7Xs
#hZ$;1.
userManager.listUser(page)即可得到一个Page对象和结果集对象 6:7[>|okQ
;=ddv@
的综合体,而传入的参数page对象则可以由前台传入,如果用 $Iwvecn?I
_F;v3|`D@<
webwork,甚至可以直接在配置文件中指定。 'BjTo*TB]Z
,twx4r^
下面给出一个webwork调用示例: esqmj#G
java代码: Fz%;_%j
e"nm< &
b|d-vnYE
/*Created on 2005-6-17*/ 52e>f5m.
package com.adt.action.user; <W"W13*j!
O,Q.-
import java.util.List; hJ}i+[~be
j<B9$8x&
import org.apache.commons.logging.Log; ;Y?MbD
import org.apache.commons.logging.LogFactory; hJ@vlMW
import org.flyware.util.page.Page; a[-!X7,IU
Q5+1'mzAB
import com.adt.bo.Result; 'dLw8&T+W
import com.adt.service.UserService; 2s\ClT
import com.opensymphony.xwork.Action; f2i:I1 p("
08`|C)Z!
/** #Vq9 =Q2
* @author Joa :aesG7=O
*/ E#B-JLMGl
publicclass ListUser implementsAction{ ?l0eU@rwQ
E7:xPNU
privatestaticfinal Log logger = LogFactory.getLog =:-fK-d
)(G9[DG
(ListUser.class); HC%Hbc~S_Q
.A2$C|a*
private UserService userService; =&WIa#!=
'a['lF
private Page page; 5?kfE
;o_F<68QP
privateList users; !(GyOAb
P!eo#b^S
/*
54+(o6E<
* (non-Javadoc) *GT=U(d
* >
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* @see com.opensymphony.xwork.Action#execute() 35<A:jKS
*/ r
)F;8(
publicString execute()throwsException{ h.jJAVPi
Result result = userService.listUser(page); 4l$OO;B
page = result.getPage(); |kYlh5/c d
users = result.getContent(); ] G&*HMtp
return SUCCESS; R6+)&:Ab{R
} q&3
;e4
gq7tSkH@
/** u,sR2&Fe
* @return Returns the page. cgg6E
O(
*/ vrnvv?HPrR
public Page getPage(){ _%w680b'
return page; j9p6rD
} #De>EQ%
#,%bW[L<N
/** DXs an
* @return Returns the users. o*cu-j3
*/ M.W
X&;>
publicList getUsers(){ T
ozx0??)
return users; (bsx|8[
} |&; ^?M
QL?_FwZL
/** z
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* @param page 0HzqU31%l@
* The page to set. -'! J?~
*/ k^J8 p#`6
publicvoid setPage(Page page){ 8<=^Rkz
this.page = page; o?`FjZ6;x
} J]F&4O
=+zDE0Qs
/** smP4KC"I(d
* @param users *_(X$qfoW
* The users to set. Nu5|tf9%A
*/ %5o2I_Cjz
publicvoid setUsers(List users){ )l3Uf&v^f
this.users = users; #[+# bw_6
} ]I?.1X5d0
uO%0rKW
/** 2|nm> 4
* @param userService u,^CFws_
* The userService to set. l2D*b93
*/ bJ~H
publicvoid setUserService(UserService userService){ DB'v7
Ij0
this.userService = userService; st-{xC#N#
} 8Q'Emw |
} $%bSRvA
Rs %`6et}\
LgqQr6y"
hlzB
cz*
]3KeAJ
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, }A)\bffH
3BFOZV+
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 9/ <3mF@E
h0{X$&:
么只需要: |Y9>kXM l
java代码: i'IT,jz!
slQn
c_J9CKqc
<?xml version="1.0"?> u` pTFy
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork VY?9|};f
c+Q'4E0|
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ++cS^ Lo
"Ep"$d
1.0.dtd"> -+R,="nRQ
vObZ|>.J~O
<xwork> MmF&jd-=
w#A)B<Y/"
<package name="user" extends="webwork- [!'+}
6Yu:v
interceptors"> &f*orM:
b^o4Q[
<!-- The default interceptor stack name djd/QAfSC
)U/jD
--> R9J!}az'
<default-interceptor-ref ZpTDM1ro
o! a,r3
name="myDefaultWebStack"/> ':*H#}Br-#
i8]EIXbMX
<action name="listUser" gabfb#
8z=#
0+0
class="com.adt.action.user.ListUser"> tsXKhS;/w
<param +
G@N
zl0{lV
name="page.everyPage">10</param> Ak'=l;
<result _imuyt".+
{bj!]j
name="success">/user/user_list.jsp</result> #<{v~sVp&
</action> MIMC(<
X/5m}-6d]
</package> `#""JTA"
i]8O?Ab>?
</xwork> zakhJ
N} EKV
0TU3
_;o
57\ 0MQO
c=!>m
9&+]YYCS-
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 K<S3gb?0
n`Q@<op
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 K;F1'5+=D
01cBAu
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Q\Ek U.[I
/%@;t@BK4
>eJ<-3L;
1J?v\S$ma`
\!u<)kkyT
我写的一个用于分页的类,用了泛型了,hoho Lqgrt]L_"
-TUJ"ep]QJ
java代码: 6VW*8~~Xy
ZW4f "
U^m#!hp
package com.intokr.util; AA\a#\#Z3
dN8Mfa)
import java.util.List; Q}BMvR 9w
z^bS+0S5x!
/** VAPeMO
ck
* 用于分页的类<br> U]PB)
* 可以用于传递查询的结果也可以用于传送查询的参数<br> !~#zd]0x;
* pH'_k k
* @version 0.01 ^<I(
* @author cheng >pq~ &)^u
*/ @16GF!.
public class Paginator<E> { (r|m&/
privateint count = 0; // 总记录数 05d0p|},
privateint p = 1; // 页编号 kK&w5'
privateint num = 20; // 每页的记录数 WzIUHNn'I
privateList<E> results = null; // 结果 IJ^~,+
'a#lBzu\b
/** 5`h$^l/
* 结果总数 lM-9 J?j
*/ !%>RHh[
publicint getCount(){ { _9O4 +
&
return count; =?5)M_6)
} FnvpnU",
GJ9>i)+h;
publicvoid setCount(int count){ yD+4YD
this.count = count; *X0>Ru[
} | {9<%Ok4P
abo=v<mR
/** .}IW!$
dq
* 本结果所在的页码,从1开始 O}M-6!%<,
* zxR]+9Zh
* @return Returns the pageNo. j=r1JV
@
*/ {npm9w<;
publicint getP(){ :=Olp;+_
return p; *,\v|]fc
} IO)B3,g
9q'9i9/3d
/** "U\RN
* if(p<=0) p=1 UtQj<18<
* )/RG-L
* @param p 4'QX1p
*/ uw;Sfx,s
publicvoid setP(int p){ VF`!ks
if(p <= 0) fyQOF ItM
p = 1; (b25g!
this.p = p; sN41Bz$q.
} a?[[F{X9^
Iz0$T.T
/** 8(1*,CJQg
* 每页记录数量 sfF ~k-
*/ ~I||"$R
publicint getNum(){ @KQ>DBWQM
return num; EI_-5Tt RD
} 1 Pk+zBJ$
~P3b5 -
/** BH:A]#_{
* if(num<1) num=1 MK1\
*/ k]m ~DVS
publicvoid setNum(int num){ P$EiD+5#z
if(num < 1) jVff@)_S
num = 1; Kg%9&l
this.num = num; P:{Aqn~zR
} WvfP9(-
(*S<2HN5
/** Am,{Fj
* 获得总页数 +?J N_aR
*/ )Zq'r L<
publicint getPageNum(){ ciS +.%7
return(count - 1) / num + 1; $nt&'Xnv
} {irc0gI
0'o[2,
/** 8iIp[9~=
* 获得本页的开始编号,为 (p-1)*num+1 \U:OQ.e
*/ g5y+F]'I
publicint getStart(){ Z^kE]Ir#EV
return(p - 1) * num + 1; A8-[EBkK
} 8~Kq"wrbu
e,%|sAs[
/** )7 57
* @return Returns the results. j_<qnBeQ
*/ DTO_IP
publicList<E> getResults(){ {$8+n::
return results; =u2 z3$
} Spn[:u @
24J c`%7,=
public void setResults(List<E> results){ p%DU1+SA
this.results = results; sxT&T=7
} o`YBz~2
'{
<RX
public String toString(){ aE~T!h
StringBuilder buff = new StringBuilder N<Sl88+U
a>47k{RSzE
(); m.lR]!Y=w
buff.append("{"); oJa}NH
buff.append("count:").append(count); #Z1%XCt
buff.append(",p:").append(p); z|pt)Xl
buff.append(",nump:").append(num); z/\OtYz
buff.append(",results:").append UFj H8jSBx
)Rn\6ka
(results); gX"-3w
buff.append("}"); \c2x
udU
return buff.toString(); cZVx4y%kz
} M'%4BOpI6`
SH)-(+72d
} wUaWF$~y
#Th)^Is
8?Rp2n*o