Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 IH*G7;
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 w,6gnO
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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 qtVgjT2#H
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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 dn~k_J=p
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分页支持类: CiU^U|~ 'L
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java代码: 4%v-)HGh
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package com.javaeye.common.util; NB3+kf ,
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import java.util.List; C.=%8|Zy
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publicclass PaginationSupport { cPL6(&7
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publicfinalstaticint PAGESIZE = 30; \RVfgfe
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privateint pageSize = PAGESIZE; W:f )#'
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privateList items; |&S^L}V.C
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privateint totalCount; =*(_sW6;
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privateint[] indexes = newint[0];
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privateint startIndex = 0; ]*DIn1C^
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public PaginationSupport(List items, int $\oe}`#o
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totalCount){ H5FWk
setPageSize(PAGESIZE); S2I{?y&K
setTotalCount(totalCount); V-%jSe<
setItems(items); q 3,p=ijJ
setStartIndex(0); l
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} F%ukT6xp
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public PaginationSupport(List items, int A9HgABhax
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totalCount, int startIndex){ O St~P^1
setPageSize(PAGESIZE); #R=6$
setTotalCount(totalCount); \o?
setItems(items); 0oyZlv*
setStartIndex(startIndex); O,&p"K&Z
} %[?{H} y
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public PaginationSupport(List items, int 5zJ#d}%}S"
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totalCount, int pageSize, int startIndex){ >y@3`u]
setPageSize(pageSize); (a|Wq{`[
setTotalCount(totalCount); \$8p8MP<&D
setItems(items); "X1{*
setStartIndex(startIndex); a^L'- (
} dBL{Mbh2Z
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publicList getItems(){ P-N+
return items; U,2\ TBz
} b\"2O4K,)
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publicvoid setItems(List items){ rYA4(rYq
this.items = items; xe1xP@e?
} O;;vz+ j
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publicint getPageSize(){ V/DdV}n!
return pageSize; `ucr;P
} }'TZ)=t{J
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publicvoid setPageSize(int pageSize){ {uO2m*JrI
this.pageSize = pageSize; :B_ itl0{e
} 'l'[U
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publicint getTotalCount(){ ""F'Nzy
return totalCount; X@7e7
} 1QDAfRx
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publicvoid setTotalCount(int totalCount){ )Chx,pcx<
if(totalCount > 0){ /aMeKM[L`
this.totalCount = totalCount; T CO^9RP<
int count = totalCount / 2fJ2o[v
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pageSize; P^bcc
if(totalCount % pageSize > 0) CbRl/ 68HY
count++; }~ o>H a;
indexes = newint[count]; h3L{zOff
for(int i = 0; i < count; i++){ kF *^" Cn
indexes = pageSize * cd*F;h
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i; \5^GUT
} iu.+bX|b
}else{ bX]$S 5c_u
this.totalCount = 0; @Nt$B'+S&
} #%tN2cFDN
} k*xgF[T
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publicint[] getIndexes(){ bQ2 '*T
return indexes; yn5yQ;
} &mp@;wI6@
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publicvoid setIndexes(int[] indexes){ fNaS?tV)
this.indexes = indexes; Q2/ZO2
} E%C02sI
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publicint getStartIndex(){ I_@XHhyVZ
return startIndex; iY1JU-S
} s5ddGiZnBT
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publicvoid setStartIndex(int startIndex){ $nbZ+~49
if(totalCount <= 0) j"8|U
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this.startIndex = 0; t.oP]_mI
elseif(startIndex >= totalCount) q6v%HF-q4
this.startIndex = indexes w;Na9tR
2s@<k1EdPl
[indexes.length - 1]; 6<<ihm+
elseif(startIndex < 0) :Yqi5CR
this.startIndex = 0; A#j'JA>_
else{ p1L8g[\
this.startIndex = indexes 'PrrP3lO_~
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[startIndex / pageSize]; /A;!g5Y
} `!\`yI$!%w
} cUz7F
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publicint getNextIndex(){ 'Nv*ePz
int nextIndex = getStartIndex() + Ey!+rq}
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pageSize; aJ1<X8
if(nextIndex >= totalCount) !bG%@{W T
return getStartIndex(); (1(dL_?
else 3Vl?;~ :5
return nextIndex; jn9KQe\3
} iWZrZ5l
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publicint getPreviousIndex(){ Q}M%
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int previousIndex = getStartIndex() - r0)X]l7
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pageSize; }?=$?3W
if(previousIndex < 0) gUB%6v G\I
return0; -&*
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else SablF2doa
return previousIndex; BV X6
} C-abc+/
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}
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抽象业务类 T8,?\7)S9
java代码: /MB3w m
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/** !>{`o/dZ
* Created on 2005-7-12 ~4\J}Kn
*/ 2WRa@;Tj
package com.javaeye.common.business; .>0j<|~
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import java.io.Serializable; 3%G>TB
import java.util.List; 0m^(|=N-
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import org.hibernate.Criteria; MV<2x7S
import org.hibernate.HibernateException; 1>1&NQ#}
import org.hibernate.Session; Gvk)H$ni
import org.hibernate.criterion.DetachedCriteria; QQUYWC
import org.hibernate.criterion.Projections; /[iqga=
import ^-9g_5
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org.springframework.orm.hibernate3.HibernateCallback; w NlC2is
import mjDaus59
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org.springframework.orm.hibernate3.support.HibernateDaoS 0wCJNXm
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upport; tO$/|B74Bz
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import com.javaeye.common.util.PaginationSupport; F(J6 XnQ
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public abstract class AbstractManager extends O9#8%p%
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HibernateDaoSupport { G'oMZb ({=
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privateboolean cacheQueries = false; B 3Y,|*
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privateString queryCacheRegion; '`#sOH
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publicvoid setCacheQueries(boolean *UVo>;
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cacheQueries){ 59;p|
this.cacheQueries = cacheQueries; ]Z?y\L*M-
} X!,2/WT
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publicvoid setQueryCacheRegion(String zrqQcnx9(m
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queryCacheRegion){ );o2eV
this.queryCacheRegion = ~)XyrKw
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queryCacheRegion; *w>dT
} E-Nc|A
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publicvoid save(finalObject entity){ tA2Py
getHibernateTemplate().save(entity); 'O%itCy)
} &DQyJJ`k
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publicvoid persist(finalObject entity){ v803@9@
getHibernateTemplate().save(entity); WZ\bm$
} A
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publicvoid update(finalObject entity){ SJg4P4|
getHibernateTemplate().update(entity); %~eIx=s
} TUw+A6u:p
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publicvoid delete(finalObject entity){ AI{Tw>hZ
getHibernateTemplate().delete(entity); ;m<22@,E&
} -][~_Hd{
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publicObject load(finalClass entity, 3K2B7loD)~
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finalSerializable id){ N~rA /B]T
return getHibernateTemplate().load rucgav
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(entity, id); S{HAFrkm7
} 0w M2v[^YO
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publicObject get(finalClass entity, -MEp0
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finalSerializable id){ 6#[
return getHibernateTemplate().get w; [ndZCY7
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(entity, id); BvQMq5&
} 1b^e4
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publicList findAll(finalClass entity){ _{Q)5ooP
return getHibernateTemplate().find("from #0HZ"n
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" + entity.getName()); 7s8-Uwl<
} {)V!wSi
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publicList findByNamedQuery(finalString LqNt.d @
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namedQuery){ >6Y@8 )
return getHibernateTemplate j) G<PW
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().findByNamedQuery(namedQuery); /\L-y,>X
} 6pJFrWe{
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publicList findByNamedQuery(finalString query, ;Gc,-BDFw
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finalObject parameter){ kq| r6uE
return getHibernateTemplate S2y_5XJ<D
tx` Z?K[
().findByNamedQuery(query, parameter); V{jQ=<)@e
} JRti2Mu
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publicList findByNamedQuery(finalString query, z):LF<
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finalObject[] parameters){ voX4A
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return getHibernateTemplate O0Z!*Hy
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().findByNamedQuery(query, parameters); =Msr+P9Ai
} F,dPmR
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publicList find(finalString query){ {lam],#r
return getHibernateTemplate().find {ef9ov Xk
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(query); Nxm^jPM0
} nXU`^<nA
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publicList find(finalString query, finalObject `T'[H/
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parameter){ U/}("i![Dy
return getHibernateTemplate().find V ,+&.A23
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(query, parameter); ~ 3!yd0[k
} hs;YMUA"
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public PaginationSupport findPageByCriteria WswM5RN
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(final DetachedCriteria detachedCriteria){ 8SZZ_tS3r
return findPageByCriteria plNoI1st
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); $?Km3N\?v
} fA$2jbGW
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public PaginationSupport findPageByCriteria Oj=g;iY
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(final DetachedCriteria detachedCriteria, finalint #]rfKHW9
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startIndex){ QLm#7ms*y
return findPageByCriteria ,+P2B%2c
d Dg[ry
(detachedCriteria, PaginationSupport.PAGESIZE, (Sv=R(_s
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startIndex); H\%^n<]#
} c9ye[81
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public PaginationSupport findPageByCriteria /4I9Elr
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(final DetachedCriteria detachedCriteria, finalint xcQD]"
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pageSize, `uwSxt
finalint startIndex){ =L\&}kzB
return(PaginationSupport) 49o /S2b4z
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getHibernateTemplate().execute(new HibernateCallback(){ lRANXM
publicObject doInHibernate /Moyn"Kj{
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(Session session)throws HibernateException { N,bH@Q.Ci
Criteria criteria = :R'={0Jg
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detachedCriteria.getExecutableCriteria(session); t5aX9WIW
int totalCount = pP-L{bT
(VM.]B<
((Integer) criteria.setProjection(Projections.rowCount &W8fEQwa
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()).uniqueResult()).intValue(); |jI|},I
criteria.setProjection ^/ff)'.J
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(null); t`-
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List items = 'WNq/z"X
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criteria.setFirstResult(startIndex).setMaxResults !ra,HkU'
z8dBfA<z
(pageSize).list(); 'F%h]4|1
PaginationSupport ps = %oOSmt
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new PaginationSupport(items, totalCount, pageSize, {,=U]^A
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startIndex); hg7_ZjO
return ps; oe*fgk/o9
} >~l^E!<i-u
}, true); #[&9~za'"m
} (kVxa8 0
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public List findAllByCriteria(final Bdcs}Ga
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DetachedCriteria detachedCriteria){ ctoh&5%!n+
return(List) getHibernateTemplate W%1/:_
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().execute(new HibernateCallback(){ l h?[wc
publicObject doInHibernate
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(Session session)throws HibernateException { q%/\
Criteria criteria = 8]i7wq#=
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detachedCriteria.getExecutableCriteria(session); nKmf#
return criteria.list(); L=@8Zi!2<
} O!'gylj/
}, true); {Ia1Wd 8n
} BZa`:ah~x
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public int getCountByCriteria(final Jz]OWb *
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DetachedCriteria detachedCriteria){ b
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Integer count = (Integer) J^=Xy(3e
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getHibernateTemplate().execute(new HibernateCallback(){ Y
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publicObject doInHibernate OYfRtfE
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(Session session)throws HibernateException { ,:{+-v(
Criteria criteria = ',1[rWyc
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detachedCriteria.getExecutableCriteria(session); ?^ R"a##
return /&E]qc*-p
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criteria.setProjection(Projections.rowCount 50dx[v8
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()).uniqueResult(); $T_>WUiK
} +Mb}70^
}, true); jItVAmC=i
return count.intValue(); ;D<;pW
} N>iNz[a
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} jFl!<ooCo
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用户在web层构造查询条件detachedCriteria,和可选的 .dn#TtQv
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 u
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PaginationSupport的实例ps。 hGI5^!Cq
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ps.getItems()得到已分页好的结果集 7e[&hea
ps.getIndexes()得到分页索引的数组 RJ-J/NhWyI
ps.getTotalCount()得到总结果数 jw)c|%r>
ps.getStartIndex()当前分页索引 `*xSn+wL`_
ps.getNextIndex()下一页索引 ky'G/z
ps.getPreviousIndex()上一页索引 BO+to.
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 v
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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 +.v+Opp,
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一下代码重构了。 paUJq?Af
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我把原本我的做法也提供出来供大家讨论吧: 0S\HO<~k
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首先,为了实现分页查询,我封装了一个Page类: Z ?ATWCa
java代码: aqgm
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/*Created on 2005-4-14*/ z3M6<.K
package org.flyware.util.page; ?[.g~DK,
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/** 16"L;r
* @author Joa k;<F33v;Mh
* xv7nChB
*/ XvZ5Q
publicclass Page { wsj5;(f+
)o;n2T#O
/** imply if the page has previous page */ FX+^S?x.
privateboolean hasPrePage; -h 21
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/** imply if the page has next page */ -3SRGr
privateboolean hasNextPage; C9j5Pd5q1L
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/** the number of every page */ :eBp`dmn
privateint everyPage; \wp8kSzC
} 7i}dyQv}
/** the total page number */ k~]\kv=
privateint totalPage; 3=_to7]
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/** the number of current page */ 0C717
privateint currentPage; rUmnv%qTS
^ lG^.
/** the begin index of the records by the current _:Ov-HIR
0Hr)h{!F"
query */ Oe0dC9H
privateint beginIndex; (Li)@Cn%
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/** The default constructor */ <7oZV^nd *
public Page(){ 8u Z4[
C7!=LiK}
} HqA3.<=F,
?e23[
/** construct the page by everyPage aIE\B4w
* @param everyPage $I a-go2W
* */ ^Y^5 @x=
public Page(int everyPage){ {6*{P!H
this.everyPage = everyPage; u"zQh|
} BtP*R,>
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&_
/** The whole constructor */ DO?
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public Page(boolean hasPrePage, boolean hasNextPage, =e]Wt/AQ
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8;P_KRaE
int everyPage, int totalPage, _1?Fyu&<5
int currentPage, int beginIndex){ mGUl/.;yp-
this.hasPrePage = hasPrePage; r<.*:]L
this.hasNextPage = hasNextPage; =_d-MJy~6
this.everyPage = everyPage; C5oIl_t
this.totalPage = totalPage; :w4I+*]
this.currentPage = currentPage; =Y5*J#
this.beginIndex = beginIndex; .w)T2(
} Jm}zit:o
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"
/** Pl[WCh
* @return h_h6@/1l
* Returns the beginIndex. 0"M0tA#
*/ e7gWz~
publicint getBeginIndex(){ b"z9Dp v
return beginIndex; 1H,hw
} P
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/** :6Sb3w5h
* @param beginIndex a<{+
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* The beginIndex to set. p%*!]JRS
*/ 7 m!e\x8
publicvoid setBeginIndex(int beginIndex){ _Y,d|!B#L
this.beginIndex = beginIndex; evHKq}{
} wB W]w
veGRwir
/** ]ipltR7k
* @return GGn/J&k
* Returns the currentPage. 9!|.b::
*/ -\=kd {*B
publicint getCurrentPage(){ pn2_ {8.
return currentPage; ek4?|!kQD
} @T+pQ)0{{
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/**
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* @param currentPage :n<<hR0d
* The currentPage to set. dNcP_l/A
*/ 4U1"F 7'
publicvoid setCurrentPage(int currentPage){ -* ;`~5
this.currentPage = currentPage; dCH(N_
} Gu136XiX
Qws#v}xF
/** k`Ifd:V.y
* @return G!IJ#|D:~
* Returns the everyPage. (1b%);L7
*/ R?[KK<sWWe
publicint getEveryPage(){ c{t(),nAA
return everyPage; (T0%H<#+
} p![CH
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/** e#$ZOK)`
* @param everyPage L1E\^)
* The everyPage to set. s"\o6r
,
*/ BpKgUwf;C
publicvoid setEveryPage(int everyPage){ A PR%ZpG
this.everyPage = everyPage; 6?c(ue iL[
} I~>L4~g)
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/** /0H39]y!~
* @return ROHr%'owgL
* Returns the hasNextPage. ,4%'~8'3
*/ yjP;o`z%
publicboolean getHasNextPage(){ MM%c
return hasNextPage; nfMQ3KP
} 8"g.Z*
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/** N;6WfdA-
* @param hasNextPage H A(e
* The hasNextPage to set. Lqv5"r7eV
*/ ]n:)W.|`R
publicvoid setHasNextPage(boolean hasNextPage){ xl$#00|y
this.hasNextPage = hasNextPage; 1(**JTe
} i
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/** ,&IBj6%Y
* @return nP >*0Fq
* Returns the hasPrePage. It@ak6u?
*/ O2Mo ~}
publicboolean getHasPrePage(){ bu#}`/\_
return hasPrePage; 7=ZB?@bU~
} NwdA@"YQ|
8PV`4=,OI
/** \ oIVE+L/P
* @param hasPrePage 81|Xg5g)b
* The hasPrePage to set. ]S~Z8T-[
*/ Dyj5a($9"{
publicvoid setHasPrePage(boolean hasPrePage){ $h-5PwHp
this.hasPrePage = hasPrePage; bG0t7~!{E
} #`mo5
pcw^W
/** mu/O\'5
* @return Returns the totalPage. ArUGa(;f
*
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*/ y3K9rf
publicint getTotalPage(){ MD,}-m
return totalPage; [a*m9F\ ,
} M"]~}*
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/** RYaf{i`
* @param totalPage <Dw`Ur^ X5
* The totalPage to set. !RnO{FL
*/ \gL
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publicvoid setTotalPage(int totalPage){ 3~4e\xL
this.totalPage = totalPage; & ;+u.X
} 4l$(#NB<
HhaUC?JtSK
} i(JBBE"
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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 |.Bb Pfe8f
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个PageUtil,负责对Page对象进行构造: gaC^<\J
java代码: u><gmp&
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/*Created on 2005-4-14*/ m[C-/f^u|
package org.flyware.util.page; */n)_
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import org.apache.commons.logging.Log; /)xG%J7H
import org.apache.commons.logging.LogFactory; u|7d_3 ::
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/** 8Z!+1b
* @author Joa k|,pj^
* 2@o_7w98
*/ FG-w7a2mn
publicclass PageUtil { H>[1DH#b
`av8|;
privatestaticfinal Log logger = LogFactory.getLog 8ltHR]v
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(PageUtil.class); ](vshgp2
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/** l,*v/95h
* Use the origin page to create a new page =/"Of
* @param page \CL |=8[2
* @param totalRecords >'/G:\M>A
* @return k=O2s'F`
*/ )kl| 5i
publicstatic Page createPage(Page page, int >UpTMEQ
3mgFouX2x,
totalRecords){ vt[4"eU
return createPage(page.getEveryPage(), 8h~v%aZ1
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page.getCurrentPage(), totalRecords); A8hj"V47
} sf]y\_zU
#"6(Q2|
l
/** EW1L!3K
* the basic page utils not including exception &3>ki0L
l0g#&V--
handler rB|D^@mG
* @param everyPage 7Rj!vj/
* @param currentPage ,*r"cmz
* @param totalRecords *~fZ9EkD
* @return page |^Z1 D TAw
*/ L*9^-,
publicstatic Page createPage(int everyPage, int n6[bF"v
/g712\?M4
currentPage, int totalRecords){ rSB"0W7
everyPage = getEveryPage(everyPage); Ywt_h;:
currentPage = getCurrentPage(currentPage); 8UoMOeI3
int beginIndex = getBeginIndex(everyPage, cn=~}T@~Z
l2=.;7IV
currentPage); 3~BL!e,
int totalPage = getTotalPage(everyPage, &TSt/b/+W
-[v:1\Vv
totalRecords); O1coay
boolean hasNextPage = hasNextPage(currentPage,
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#;a
1=8H
totalPage); 7(eWBJfTo
boolean hasPrePage = hasPrePage(currentPage); Fg?Gx(g4
qI<6% ^i
returnnew Page(hasPrePage, hasNextPage, ,v$gQU2
everyPage, totalPage, X}_}`wIn
currentPage, (80]xLEBL
U
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beginIndex); JTpKF_Za<
} B @UaaWh
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privatestaticint getEveryPage(int everyPage){ rOB-2@-
return everyPage == 0 ? 10 : everyPage; G!oq
;<
} YU[93@mCh
8[ 1D4d
privatestaticint getCurrentPage(int currentPage){ a|32Pn
return currentPage == 0 ? 1 : currentPage; Rs{L
} Qwk
oKz|hks[6
privatestaticint getBeginIndex(int everyPage, int Uq~{=hMX
|h*H;@$
currentPage){ i=reJ(y-
return(currentPage - 1) * everyPage; ]~87v
} Us M|OH5k
ME1lQ7E4B
privatestaticint getTotalPage(int everyPage, int "4H&wHhT!
e\ k=T}
totalRecords){ 7<AHQ<#@
int totalPage = 0; [L|H1ll
AGn:I??
if(totalRecords % everyPage == 0) DL|,:2`
totalPage = totalRecords / everyPage; 9]VUQl9gh
else >z
h
totalPage = totalRecords / everyPage + 1 ; ]o_Z3xXUa
;)5d
wq
return totalPage; hv}rA,Yd
} Q4TI '/
EkEM|<GNd
privatestaticboolean hasPrePage(int currentPage){ AASw^A3p
return currentPage == 1 ? false : true; z*YkD"]B
} %z J)mOu
AR]y p{NS
privatestaticboolean hasNextPage(int currentPage, II)\rVP5
PLKp<kg
int totalPage){ IBf&'/ 8\
return currentPage == totalPage || totalPage == WHqp7NPl
s,"<+80%
0 ? false : true; Bra>C
} <G{m=
yd`xmc)
h5U@Ys
} fr;>`u[;
vO%n~l=
Iu jly f
?a7PxD.
n wToZxHZ~
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。 >,y291p2
W @`Nn*S
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 3)T'&HKQ
*O#%hTYq
做法如下: kUmrJBh$
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 \^iJv~d
E08FUAth]#
的信息,和一个结果集List: "'4R_R
java代码:
X~sl5?
,_r"=>?@
dZIAotHN:
/*Created on 2005-6-13*/ H`njKKdR
package com.adt.bo; 7UejK r
m(s(2wq"f
import java.util.List; G`8gI)$u
iP~5=
import org.flyware.util.page.Page; LpGplDlB
&&xBq?
/** '~VKH}b
* @author Joa %UI.E=`n
*/ (#BkL:dg
publicclass Result { e Pq(:ih
a57Y9.H`o
private Page page; xM8}Xo
A)kx,,[
private List content; ]U!vZY@\
f'0n^mSP
/** aA-A>z
* The default constructor 4!i`9w$$"
*/ u01 'f-h
public Result(){ sD7Qt
super(); ;3U-ghj
} & 1p\.Y
UZi^ &
/** gYA|JFi
* The constructor using fields &8_]omuNV
* ]iRE^o6
* @param page *&q\)\(3w
* @param content "fdgBso
*/ A07g@3n
public Result(Page page, List content){ --d<s
this.page = page; 8;ke,x
this.content = content; S(.AE@U
} iE=Yh
=<e|<EwSZ
/** (wEaa'XL
* @return Returns the content. L@HPU;<
*/ }=z_3JfO
publicList getContent(){ Y;8Y s&/t
return content; _7'9omq@
} 8*!<,k="9
mTz %;+|L
/** ]|it&4l
* @return Returns the page. Tz4,lwuWX7
*/ uz-,)
public Page getPage(){ NZ djS9
return page; R
5-q{
} <k<K"{
KtchKpv
/** =dx!R ,Bw
* @param content _Db=I3.HJ
* The content to set. vH%AXzIA
*/ <vJPKQ`=:
public void setContent(List content){ K*&M:u6E
this.content = content; Py$Q]s?\1
} {YC!pDG
Ehi)n)HhG"
/** f.JZ[+
* @param page mE'y$5ZxY
* The page to set. ye:pGa w
*/ /x,gdZPX
publicvoid setPage(Page page){ rZ2X$FO@
this.page = page; b6:A-jb*I
} PElC0qCn[
} <cNXe4(
WSi`)@.XO
NUbw]Y90~
u~[HC)4(0
fuSfBtLPR#
2. 编写业务逻辑接口,并实现它(UserManager, LSQWveZz
59!yz'feF
UserManagerImpl) t~ruP',~\
java代码: $}V<Um
zI$^yk-vn
Z"#eN(v.N
/*Created on 2005-7-15*/ l9KLP
package com.adt.service; 8@]*X,umc
.)
uUpY%K^
import net.sf.hibernate.HibernateException; B4 yU}v
*GleeJWz
import org.flyware.util.page.Page; |x@)%QeC
PtCO';9[
import com.adt.bo.Result; NAjY,)>'K
G6(kwv4
/** 4)0 %^\p
* @author Joa QEKSbxL\W
*/ Z:DEET!c'k
publicinterface UserManager { RO[Ko-m|/N
J ^gtSn^
public Result listUser(Page page)throws O4RNt,?l
~\kJir
HibernateException; s7.2EkGl=
W&CQ87b
} <k?ofE1o
b~fX=!M
A<P3X/i
bwo-9B
KiYO,nD;\
java代码: 1c_gh12
^ CVhV
cpvN
}G
/*Created on 2005-7-15*/ 9<u^.w
package com.adt.service.impl; @Gp=9\L
1{+x >Pv:
import java.util.List; g? N~mca$
N1,=5P$
import net.sf.hibernate.HibernateException; DTmv2X
)*#Pp )Q
import org.flyware.util.page.Page; i; Cs,Esnf
import org.flyware.util.page.PageUtil; M2HO!btf
ALvj)I`Al
import com.adt.bo.Result;
bj23S&
import com.adt.dao.UserDAO; \Zc$X^}vN
import com.adt.exception.ObjectNotFoundException; u>c\J|K_V
import com.adt.service.UserManager; 9rXbv4{
w}+#w8hu
/** x{4Rm,Dxn
* @author Joa T'\B17
:*
*/ !OWPwBm;
publicclass UserManagerImpl implements UserManager { 'F%4[3a$\n
n][/c_]q
private UserDAO userDAO; 3ThBy'
06DT2
/** }
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* @param userDAO The userDAO to set. ].F7.
zi
*/ @_"B0$,-i
publicvoid setUserDAO(UserDAO userDAO){ 1=BDqSZ@9
this.userDAO = userDAO; Td#D\d\R
} V.zKjoky@
@sQ^6FK0G
/* (non-Javadoc) lyGQ6zlSn
* @see com.adt.service.UserManager#listUser 79 zFF
0#(K}9T)
(org.flyware.util.page.Page) uC\FW6K=m
*/ #oRm-yDr
public Result listUser(Page page)throws )E;+C2G
z ogtIn)
HibernateException, ObjectNotFoundException { Y[%1?CREP
int totalRecords = userDAO.getUserCount(); HScj
if(totalRecords == 0) +|}R^x`z
throw new ObjectNotFoundException :g)0-gN
g8^\|
("userNotExist"); W>C!V
page = PageUtil.createPage(page, totalRecords); v*Tliw`-U
List users = userDAO.getUserByPage(page); hsV+?#I
returnnew Result(page, users); )aoB-Lu
} is=sV:j:
+mRFHZG
} /H#- \r&r
2|'v[
WrK!]17or
rZRcy9$y>
eXJt9olI
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >!+.M9
]zp5 6U|xa
询,接下来编写UserDAO的代码: 3:Bwf)*
3. UserDAO 和 UserDAOImpl:
!sda6?&
java代码: }e3M5LI1L
whb|N2
DLMG<4Cd~
/*Created on 2005-7-15*/ H /Idc,*
package com.adt.dao; IV{,'+hT
y*2R#jTA
import java.util.List; [NcS[*qp
gfE<XrG
import org.flyware.util.page.Page; (;u tiupW
d,=Kv
import net.sf.hibernate.HibernateException; /lAB
?pgdj|"a
/** w:Ui_-4*>
* @author Joa CU=}]Y
*/ P.*J'q 28
publicinterface UserDAO extends BaseDAO { nb(4"|8}
!_GY\@}
publicList getUserByName(String name)throws 4)D#kP
mhnjYK9
HibernateException; Zu(eYH=Q
8@%Xd^
publicint getUserCount()throws HibernateException; [% chN/
}Ictnb
publicList getUserByPage(Page page)throws :V2"<]
`-zdjc d
HibernateException; *]2LN$
xt]Z{:.
} SQ#6~zxl
d
q=>-^o
l@`D;m
NfLvK o8
l,uYp"F,ps
java代码: eeIh }t>[
+3.Ik,Z}zq
N[4v6GS
/*Created on 2005-7-15*/ }HS:3Dt
package com.adt.dao.impl; ?]gZg[
Ke[doQ#c
import java.util.List; .(o]d{ '-}
Li ,B,
import org.flyware.util.page.Page; E_&Hje|J_[
".L+gn}u-
import net.sf.hibernate.HibernateException; Tk s;,C
import net.sf.hibernate.Query; fs4pAB #F
d7N;Fa3yL
import com.adt.dao.UserDAO; M ,V+bt
[+$l/dag
/** `NA[zH,w3
* @author Joa Cpaeo0Oq
*/ <'A>7M~h?*
public class UserDAOImpl extends BaseDAOHibernateImpl C%d 4ItB >
g+/%r91hZ
implements UserDAO { !-
f>*|@
3WyK!@{
/* (non-Javadoc) j&E4|g (
* @see com.adt.dao.UserDAO#getUserByName tb,.f3;
$w%oLI@kl
(java.lang.String) ,2S
<#p!
*/ /2^cty.BXw
publicList getUserByName(String name)throws hT6:7_UD
*ggTTHy
HibernateException { GkMNV7"m
String querySentence = "FROM user in class gd<8RVA
oTZ?x}Z1
com.adt.po.User WHERE user.name=:name"; Sp)KtMV
Query query = getSession().createQuery SCeZt [
Pg[zRRf<
(querySentence); Qi Wv
query.setParameter("name", name); 1!8*mk_R{
return query.list(); 20m6-rkI<}
} P
Y
+~,T2
d$ Mk
/* (non-Javadoc) ezTu1-m
* @see com.adt.dao.UserDAO#getUserCount() 1_:1cF{w
*/ UwtOlV:G{
publicint getUserCount()throws HibernateException { Bp\io$(%
int count = 0; C>cc!+n%H
String querySentence = "SELECT count(*) FROM g$VcT\X
o^~6RZ
user in class com.adt.po.User"; Gb61X6
Query query = getSession().createQuery O%9Cq}*
'R*gSqx~
(querySentence); /Nq!^=
count = ((Integer)query.iterate().next ~J2-B2S!
V5rnI\:7
()).intValue(); ^7q=E@[e
return count; !mBsDn(J
} X[k-J\
$N;!. 5lX3
/* (non-Javadoc) Lhl)p P17
* @see com.adt.dao.UserDAO#getUserByPage a#H=dIj
:w_F<2d0
0
(org.flyware.util.page.Page) ]Oc
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*/ $o\p["DP
publicList getUserByPage(Page page)throws 3iYz<M
fEs957$
HibernateException { `'Ta=kd3
String querySentence = "FROM user in class ;t%L(J
|PH]0.m5
com.adt.po.User"; !~UI~-i'
Query query = getSession().createQuery y:4Sw#M%(
;0E"4(S.q1
(querySentence); j-gLX
query.setFirstResult(page.getBeginIndex()) ;TSnIC)c
.setMaxResults(page.getEveryPage()); 2BH>TmS
return query.list(); a2/r$Tgm
} 9?D7"P+
s
cR-|GuZ
} &_4A6
UTA0B&aB
+lJuF/sS8m
37p0*%a":
$ajw]2kx
至此,一个完整的分页程序完成。前台的只需要调用 B0p>' O2
SUD]Wl7G`r
userManager.listUser(page)即可得到一个Page对象和结果集对象 =)M 8>>l
};9dd3X
的综合体,而传入的参数page对象则可以由前台传入,如果用 %W"\
PkDL\Nqe
webwork,甚至可以直接在配置文件中指定。 gZM{]GQ
L:Wy- Z
下面给出一个webwork调用示例: b("CvD8
java代码: ^S ,E "Q
miS+MK"
{J})f>x<xM
/*Created on 2005-6-17*/ %>I!mD"X\
package com.adt.action.user; !P@u4FCs
yfTnj:Fz
import java.util.List; n_Um)GI>
u;J= g
import org.apache.commons.logging.Log; \(T;@r
import org.apache.commons.logging.LogFactory; ?;)(O2p
import org.flyware.util.page.Page; _Fl]zs<
pE `Q4:<A
import com.adt.bo.Result; 6$PfX.Fh
import com.adt.service.UserService; gp-wlu4
import com.opensymphony.xwork.Action; *XH?|SV
Byldt
/** ccD+o$7LT
* @author Joa Xz]}cRQ[
*/ aS~k.^N
publicclass ListUser implementsAction{ 6 /4OFvL1
"vLqYc4$
privatestaticfinal Log logger = LogFactory.getLog nOQ+oqM<
R2]?9\II
(ListUser.class); :NbD^h)R
O.rk!&N
private UserService userService; v@>hjie
+Yi=Wo/
private Page page; oeIB1DaI
XQj`KUO@
privateList users; 5\|[)~b
Br#]FB|tD
/* ]
{NY;|&I'
* (non-Javadoc) ,6t0w|@-k
* aF'Ik XG d
* @see com.opensymphony.xwork.Action#execute() *otJtEI>6
*/ Yf {s0Z
publicString execute()throwsException{ W@wT,yJ8@
Result result = userService.listUser(page); S<p
"k]
page = result.getPage(); sK?[1BI
users = result.getContent(); ?rBj{]=
return SUCCESS; 8(3vNuyP
} -^#Ix;%
)_j.0a
/** |:!0`p{R
* @return Returns the page. ;uoH+`pf
*/ K?I@'B'
public Page getPage(){ "#4PU5.
return page; -D!F|&$
} P:*'x9`
g"T~)SQP
/** 2YwV}
* @return Returns the users.
5j]}/Aq
*/ {xM%3
publicList getUsers(){ ~]"}s(J;
return users; Q;5\( 0w5
} HwU \[f
*39sh[*}
/** 3N]pN<3@
* @param page Q 5@~0
* The page to set. j,1,;
*/ <EBp X
publicvoid setPage(Page page){ sXhtn'<v
this.page = page; 8:t-I]dzk
} a[(n91J0
i( c2NPbX
/** Q;aZpi-E"
* @param users 2&tGJq-E
* The users to set. u|QfCwQ
*/ 6eS#L2 1*
publicvoid setUsers(List users){ :=i0$k<E/
this.users = users; /au\OBUge
} L3<XWpv
hlUF9}
/** Nju7!yVM_
* @param userService W1:o2 C7
* The userService to set. ,Y`C7Px
*/ ?<nz2 piP,
publicvoid setUserService(UserService userService){ |_w*:NCV5
this.userService = userService; @'}X&TN<a
} -TD6s:'
} DJ<c
Zb9@U: \
}(hE{((o
+i)1 jX<
^ g4)aaBZ
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Y^6=_^
t: [[5];E
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 XD|&{/O
DG:=E/ @
么只需要: :\bttPw5
java代码: @8CD@SDv
LZoth+:
x%(!+
<?xml version="1.0"?> ikxSWO_Y=
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ho(Y?'^t3
_O rE{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Y/$SriC_+'
_8S).*
1.0.dtd"> J@Orrz2q#
%
tJ?dlD'
<xwork> X`aED\#\h
+pFz&)?
<package name="user" extends="webwork- N7;E 2 X
i5AhF\7F9
interceptors"> (=PnLP
>Y\4v}-
<!-- The default interceptor stack name st+Kz uK
S((8DSt*
--> He]F~GXP
<default-interceptor-ref ntF(K/~Y
#JW1JCT
name="myDefaultWebStack"/> EAq >v
t83
1gt[_P2u
<action name="listUser" d@w
I:
7
Yb6\+}th
class="com.adt.action.user.ListUser"> qkBnEPWZy
<param qb9%Y/xy
WYh7Y
name="page.everyPage">10</param> 5o72X k
<result >)5vsqGZaK
;J5oO$H+68
name="success">/user/user_list.jsp</result> 3;M!]9ms
</action> 3 $kZu
&G"]v]V
</package> XSxya.1
3(}?f
</xwork> -~-2 g
'{+hti,Lh
_rR.Y3N
a%]p*X!
@+2Zt%
V2y[IeSQ
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 P `oR-D
D=OU61AA
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 6@$[x* V
' 5Ieqpm9
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 au7BqV!uL
qMUqd}=P
\agC Q&
?3|ZS8y
eU12*(
我写的一个用于分页的类,用了泛型了,hoho )l"0:1I g
S4(IYnwN
java代码: V*TG%V -
b,@:eVQ7
2`},;i~[
package com.intokr.util; bc"{ZL!C
z7K?rgH
import java.util.List; 3dM6zOK
2MC\~"L<
/** 81n%2G
* 用于分页的类<br> TcIUo!:z
* 可以用于传递查询的结果也可以用于传送查询的参数<br> P*LcWrK
* dqkkA/1
* @version 0.01 Y9%yjh
* @author cheng 8jZYy!
*/ $wN .~"T
public class Paginator<E> { )N=wJN1
privateint count = 0; // 总记录数 YM;^c%
_7
privateint p = 1; // 页编号 Oh^X^*I$@
privateint num = 20; // 每页的记录数 8%NX)hZyq}
privateList<E> results = null; // 结果 dqe_&C@*O
^g0 Ig2'
/** E`s_Dr}K
* 结果总数 pQ/:*cd+M
*/ L fi]s
publicint getCount(){ }E=kfMu
return count; tyDtwV|
} )CmuC@ Q"
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publicvoid setCount(int count){ OYzJE@r^
this.count = count; ZN)/doK
} SB;Wa%
y,
Z#?O
/** =#u2Rx%V
* 本结果所在的页码,从1开始 h1Lp:@:|
* $-y+97
* @return Returns the pageNo. 646yeQ1
*/ m<yA]
';s
publicint getP(){ J8%|Gd0#4
return p; IQ_0[
} Cjh&$aq
Q?>#sN,
/** wiVQMgi`
* if(p<=0) p=1 ?1{`~)"
* d.+vjMI
* @param p XX F9oy8
*/ JC#@sJ4az)
publicvoid setP(int p){ Dux`BKl
if(p <= 0) G^R;~J*TDE
p = 1; -Z Z$
1E
this.p = p; 06`__$@h
} _(jE](,
UqHO S{\Sz
/** Z 0:2x(x9
* 每页记录数量 1_t Dp&UO
*/ d;=,/a
publicint getNum(){ 9j 8t<5s
return num; OBl8kH(b>
} ZMe| fn
3 x'30
/** X+3)DE\2
* if(num<1) num=1 e\dT~)c
*/ 2eK\$_b_
publicvoid setNum(int num){ y((_V%F}
if(num < 1) WY,t> 1c
num = 1; ^Pf&C0xXv
this.num = num; Fv: %"P^
} <\8
=oTYwU
/** U&5zs r
* 获得总页数 W
wE)XE
*/ WU4i-@Bm8
publicint getPageNum(){ sHuz10
return(count - 1) / num + 1; V588Leb?
} qh'BrYu*
GlZ9k-ZRF
/** [E^X=+Jnz
* 获得本页的开始编号,为 (p-1)*num+1 g-^m\>B
*/ oD7H6\_
publicint getStart(){ oL@ou{iQ
return(p - 1) * num + 1; -7$'* V9$
} {q)B@#p
h=tu+pn
/** 16y$;kf8
* @return Returns the results. c-T
^
aR
*/
gh}AD1TN]
publicList<E> getResults(){ >(rB[ZJ
return results; ^;3rdBprm
} CJOl|"UyJ
]aRD6F:L
public void setResults(List<E> results){ `|w#K28t"
this.results = results; ]*@$%iCPE
} "6dbRo5%
Zz-;jkX)
public String toString(){ \k=Qq(=
StringBuilder buff = new StringBuilder Vr1|%*0Tv
>l1Yhxd_0*
(); IpJ v\zH7
buff.append("{"); O)|4>J*B
buff.append("count:").append(count); rsv!mY,Em
buff.append(",p:").append(p); ;5k|gW
buff.append(",nump:").append(num); 6y_Z'@L
buff.append(",results:").append [J`G`s!
gk1S"H
(results); orHD3T%&
buff.append("}"); 5r<(Z0
return buff.toString(); j*u9+.
} 0_
\ g
h /QP=Zd
} :\JbWj_j
N^]>R:Stu
4Jr[8P0/A9