Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 h/s8".\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 u.yjk/jF
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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 TxA%{0
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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 DeK&_)g| Z
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分页支持类: 8-5g6qAS
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java代码: *L{^em#b
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package com.javaeye.common.util; 4R}$P1 E
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import java.util.List; M+l~^E0Wj
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publicclass PaginationSupport { -IE=?23Do?
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publicfinalstaticint PAGESIZE = 30; E0t%]?1
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privateint pageSize = PAGESIZE; W.sH
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privateList items; !QsmT3
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privateint totalCount; Dzr(Fb
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privateint[] indexes = newint[0]; MA+{7 [
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privateint startIndex = 0; 6^QSV@N|
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public PaginationSupport(List items, int :G4)edwe
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totalCount){ l\6.f_
setPageSize(PAGESIZE); /St d6B*
setTotalCount(totalCount); (.~,I+Cz'
setItems(items); tSX,*cz
setStartIndex(0); Z}`A'#!
} rCsH
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public PaginationSupport(List items, int wDt9Lf
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totalCount, int startIndex){ fq(3uE]nC
setPageSize(PAGESIZE); g0k{b
setTotalCount(totalCount); $h|8z
setItems(items); .2f0e[J
setStartIndex(startIndex); q^Ui2
} *@E&O^%cO
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public PaginationSupport(List items, int >>.4@
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totalCount, int pageSize, int startIndex){ 9xRor<
setPageSize(pageSize); >jRH<|Az
setTotalCount(totalCount); f^[u70c82
setItems(items); w)<h$<tU
setStartIndex(startIndex); {s3 j}&
} :pNu$%q
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publicList getItems(){ ^K?Mq1"Db
return items; 55V&[>|K5
} +nKf ^rG
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publicvoid setItems(List items){ OE(!^"5?[
this.items = items; ."h>I @MH
} `{+aJ0<S
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publicint getPageSize(){ X8~gLdv8
return pageSize; D8=a +!l-
} PS/00F/Ak
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publicvoid setPageSize(int pageSize){ [J6q(}f
this.pageSize = pageSize; UEH+E&BCC
} ^~DClZ
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publicint getTotalCount(){ /9<62F@zJ"
return totalCount; MuP&m{
} ]-8yZWal
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publicvoid setTotalCount(int totalCount){ $@eFSA5k,7
if(totalCount > 0){ 6B&ERdoX
this.totalCount = totalCount; G0Wv=tX|
int count = totalCount / K&;;{~md.
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pageSize; HyJ&;4rf
if(totalCount % pageSize > 0) q/3 )yG6s
count++; - %`iLu
indexes = newint[count]; *:,y`!F=y
for(int i = 0; i < count; i++){ _Bq [c
indexes = pageSize * D`@*udn=
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i; "a]Ff&T-
} 1J[|Ow
}else{ TU O*w
this.totalCount = 0; ;2Za]%'
} *v0}S5^/"
} 89l{h8R
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publicint[] getIndexes(){ r1AG1Y
return indexes; }Oe9Zq
} q|xic>.
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publicvoid setIndexes(int[] indexes){ O;SD90
this.indexes = indexes; iNEE2BPp
} @WO>F G3
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publicint getStartIndex(){ $#HUxwx4
return startIndex; Sj9NhtF]f
} M|\C@,F]8
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publicvoid setStartIndex(int startIndex){ |C3~Q{A
if(totalCount <= 0) {on+
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this.startIndex = 0; Jsw%.<
elseif(startIndex >= totalCount) Bw*6X`'Q
this.startIndex = indexes /]hE?cmj
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[indexes.length - 1]; YY9Ub
elseif(startIndex < 0) ;eiqzdP
this.startIndex = 0; )NCSO b
else{ [LrA_N
this.startIndex = indexes L7 g4'
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[startIndex / pageSize]; JB(P-Y#yyA
} #NR9\
} u{(-`Al}L
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publicint getNextIndex(){ (VH0+
int nextIndex = getStartIndex() + h$I
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pageSize; |c3Yh,Sv
if(nextIndex >= totalCount) jLgx(bMn
return getStartIndex(); )@\m0bnF
else X0Zr?$q
return nextIndex; WJ
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} hwB>@r2
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publicint getPreviousIndex(){ Y|y X]\,
int previousIndex = getStartIndex() - B4ky%gF4
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pageSize; M,/{ 53
if(previousIndex < 0) =3<@{^Eg
return0; N[8y+2SZ
else ["
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return previousIndex; ?R\:6x<
} dT4e[4l
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} iTg7@%
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抽象业务类 >2@ a\
java代码: KvfZj
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/** QP0[
* Created on 2005-7-12 n
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*/ +Rb0:r>kU
package com.javaeye.common.business; aIW W[xZ
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import java.io.Serializable; {fAj*,pzl
import java.util.List; fY{&W@#g
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import org.hibernate.Criteria; (b4;c=<[{
import org.hibernate.HibernateException; @gHWU>k,A
import org.hibernate.Session; - |j4u#z
import org.hibernate.criterion.DetachedCriteria; TWk1`1|
import org.hibernate.criterion.Projections; 2$%E:J+2:$
import @N,I}_ 9-
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org.springframework.orm.hibernate3.HibernateCallback; sCw X|
import EABy<i
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org.springframework.orm.hibernate3.support.HibernateDaoS 990sE
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upport; -+w^"RBV
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import com.javaeye.common.util.PaginationSupport; DV">9{"5']
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public abstract class AbstractManager extends PDH00(#;+
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HibernateDaoSupport { N0 F|r8xS
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privateboolean cacheQueries = false; p.J+~s4G
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privateString queryCacheRegion; Z2wgfP`
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publicvoid setCacheQueries(boolean t:<dirw,o
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cacheQueries){ 8!q$8]M
this.cacheQueries = cacheQueries; .<|.nK` 6
} 9Di@r!Db
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publicvoid setQueryCacheRegion(String aO]FQ#l2b
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queryCacheRegion){ rS/}!|uAu
this.queryCacheRegion = >:yU bo)
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queryCacheRegion; x&PVsXdt5m
} ,@*Srrw
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publicvoid save(finalObject entity){ qqR8E&Y{
getHibernateTemplate().save(entity); l{b*YUsz>
} BvA09lK
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publicvoid persist(finalObject entity){ _[_mmf1;:'
getHibernateTemplate().save(entity); @g~hYc
} c5e
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publicvoid update(finalObject entity){ 6xsB#v*
getHibernateTemplate().update(entity); J&bhR9sF
} rBY{&JhS
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publicvoid delete(finalObject entity){ =
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getHibernateTemplate().delete(entity); hR1n@/nh
} 4`Z8EV
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publicObject load(finalClass entity, CYCG5)<9
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finalSerializable id){ 'YaD=""
return getHibernateTemplate().load [esR!})
}co*%F{1
(entity, id); _jr'A -M
} ^Td_B03)
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publicObject get(finalClass entity, ?U;KwS]%
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finalSerializable id){ K
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return getHibernateTemplate().get &+Iv"9
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(entity, id); ZSo#vQ
} %tRQK$]c
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publicList findAll(finalClass entity){ Cm5:_K`;]
return getHibernateTemplate().find("from R^*h|7)E
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" + entity.getName()); |VPJaiC~
} vS$_H<;P
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publicList findByNamedQuery(finalString W$X@DXT=o
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namedQuery){ |d B`URP
return getHibernateTemplate c>(`X@KL
_ Db05:r@
().findByNamedQuery(namedQuery); keYvscRBI
} :~1sF_
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publicList findByNamedQuery(finalString query, ^*fZ
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finalObject parameter){ ojA i2uz
return getHibernateTemplate 10 D6fkjf
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().findByNamedQuery(query, parameter); 8 FqhSzw
} RTgR>qI&)
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publicList findByNamedQuery(finalString query, -!kfwJg8N(
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finalObject[] parameters){ v_$'!i$
return getHibernateTemplate 4CT _MAj
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().findByNamedQuery(query, parameters); L
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} 8a;I,DK=j
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publicList find(finalString query){ Q0\tK=Z/
return getHibernateTemplate().find d,R
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(query); ]^j'2nJv0
} Snav)Hb'
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publicList find(finalString query, finalObject M,ObzgW
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parameter){ W_##8[r(?
return getHibernateTemplate().find ;hsem,C h7
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(query, parameter); [=
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}
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public PaginationSupport findPageByCriteria *XCid_{(
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(final DetachedCriteria detachedCriteria){ h5:>o
return findPageByCriteria m\}8N
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); z DP
} g@<E0
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public PaginationSupport findPageByCriteria oBm^RHTZ
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(final DetachedCriteria detachedCriteria, finalint !2R<T/9~
n8!qz:z/
startIndex){ QX'EMyK$
return findPageByCriteria 0x-58i0
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(detachedCriteria, PaginationSupport.PAGESIZE, bvuoo/
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startIndex); |9;6Cp
} ,EAf/2C
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public PaginationSupport findPageByCriteria ~is$Onf99#
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(final DetachedCriteria detachedCriteria, finalint /lC&'h T
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pageSize, TH`zp]0
finalint startIndex){ %SwN/rna
return(PaginationSupport) z g@,s"`>
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getHibernateTemplate().execute(new HibernateCallback(){ nY#V~^|
publicObject doInHibernate wO&edZ]zb^
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(Session session)throws HibernateException { M%3 \]&
Criteria criteria = rl\$a2_+
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detachedCriteria.getExecutableCriteria(session); qm.30 2
int totalCount = ^st.bzg+[
0u?{"xH{+}
((Integer) criteria.setProjection(Projections.rowCount yC]xYn)
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()).uniqueResult()).intValue(); ^&AhWm7\
criteria.setProjection FAS+*GFz
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(null); ^k'?e"[gTs
List items = a^vXwY
#!m`A+!~!
criteria.setFirstResult(startIndex).setMaxResults 8fn7!
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(pageSize).list(); Xm|Uz`A;
PaginationSupport ps = f1a >C
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new PaginationSupport(items, totalCount, pageSize, y;!q E~!3
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startIndex); hrT_0FZV
return ps; %<g(EKl
} 6N%fJ
}, true); "funFvY
} 8$|<`:~J
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public List findAllByCriteria(final aw0;
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DetachedCriteria detachedCriteria){ ~{#$`o=
return(List) getHibernateTemplate >t[beRcR6
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().execute(new HibernateCallback(){ ];-DqK'
publicObject doInHibernate ~\4B 1n7
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(Session session)throws HibernateException { dFd^@b
Criteria criteria = D^?jLfW8
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detachedCriteria.getExecutableCriteria(session); _^)Wrf+
return criteria.list(); 4@K9%
} 6I$laHx?
}, true); LP{{PT.&X
} 0Cox+QJt
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public int getCountByCriteria(final _f~(g1sE
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DetachedCriteria detachedCriteria){ 7j>NUx=j3
Integer count = (Integer) ^4+ew>BLSv
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getHibernateTemplate().execute(new HibernateCallback(){ d},IQ,Az:Z
publicObject doInHibernate 5wy1%/;
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(Session session)throws HibernateException { KjrUTG0oA
Criteria criteria = ~wMdk9RQ
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detachedCriteria.getExecutableCriteria(session); *4i)aj
return O8;`6r
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criteria.setProjection(Projections.rowCount F{:ZHCm
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()).uniqueResult(); b7
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} X5@SLkJ-`
}, true); ^w0V{qF{
return count.intValue(); 61Z#;2]
} r/X4Hy0!lT
} U4DQ+g(A
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用户在web层构造查询条件detachedCriteria,和可选的 7eQE[C
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 1g_(xwUp+
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PaginationSupport的实例ps。 p!+7F\
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ps.getItems()得到已分页好的结果集 qf/1a CQiP
ps.getIndexes()得到分页索引的数组 +Zaew679
ps.getTotalCount()得到总结果数 ~R;9a"nr
ps.getStartIndex()当前分页索引 \hjGw,d
ps.getNextIndex()下一页索引 16iymiLz&
ps.getPreviousIndex()上一页索引 !Gv*iWg
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Fq{Z-yVp
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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 #RE
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一下代码重构了。 Gj[+{
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我把原本我的做法也提供出来供大家讨论吧: 4_CV.?
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首先,为了实现分页查询,我封装了一个Page类: Wvhg:vup
java代码: }uI(D&?+h
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/*Created on 2005-4-14*/ Mo+mO&B
package org.flyware.util.page; NDG3mCl
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/** ~,
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* @author Joa @ljvTgZ(X
* %ZNp
*/ -1tdyCez
publicclass Page { J 4$^Hr
!J34yro+s
/** imply if the page has previous page */ cJEOwAN
privateboolean hasPrePage; TBfX1v|Z)
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/** imply if the page has next page */ 5K1WfdBX7)
privateboolean hasNextPage; X(D$eV
!i0jk,[B=
/** the number of every page */ /Q7cQ2[EU
privateint everyPage; :!omog
j@1rVOmK
/** the total page number */ E,Q>jH
privateint totalPage; GCxtW FXH
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/** the number of current page */ )ca^%(25!z
privateint currentPage; @w1@|"6vF
| v?
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/** the begin index of the records by the current DRldRm/
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query */ RU>Hr5ebo
privateint beginIndex; p_!;N^y.
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/** The default constructor */ $9GRA M.
public Page(){ ^!]Hm&.a
,"U8Fgf[r
} !/4f/g4Ze
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/** construct the page by everyPage !6eXJ#~[E
* @param everyPage RP]hW{:U
* */ 1vcI`8%S+u
public Page(int everyPage){ KtWG2
this.everyPage = everyPage; ]w _,0q
} 1Aq*|JSk(
)7mX]@
/** The whole constructor */ y(pHt
public Page(boolean hasPrePage, boolean hasNextPage, r7tN(2;5
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int everyPage, int totalPage, lFWN[`H
int currentPage, int beginIndex){ P) fv:a
this.hasPrePage = hasPrePage; q% Eze
this.hasNextPage = hasNextPage; |Rr^K5hmD
this.everyPage = everyPage; &a?&G'?
this.totalPage = totalPage; &"dT/5}6
this.currentPage = currentPage; Rd5ni2-nve
this.beginIndex = beginIndex; "ei*iUBN:
} M\wIpRD,
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/** L[zg2y
* @return eSZS`(#!(
* Returns the beginIndex. B;'Dh<J1
*/ *|n::9
publicint getBeginIndex(){ [/#c9RA
return beginIndex; t<O5_}R%d
} w=I'
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/** aa<9%j
* @param beginIndex ~Mv@Bl
* The beginIndex to set. 6KiI3%y?0
*/ T`g.K6$b
publicvoid setBeginIndex(int beginIndex){ fI%+
this.beginIndex = beginIndex; *uR&d;vg.8
} (~/VP3.S
!UE'
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/** _S:6;_bz
* @return gWp\?La
* Returns the currentPage. hWK}] gF
*/ cq'opjLf 5
publicint getCurrentPage(){ q!#e2Dx
return currentPage; vjG:
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} Hz$l)g}U
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/** !Gu,X'#Ab
* @param currentPage u49zc9
* The currentPage to set. `fEB,0j^
*/ &x{CC@g/
publicvoid setCurrentPage(int currentPage){ nu,#y"WQ
this.currentPage = currentPage; qO=_i d
} #5GIO
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/** YmM+x=G:
* @return VOBzB]
* Returns the everyPage. u7>b}+ak&
*/ @sly-2{e1
publicint getEveryPage(){ D'aq^T'
return everyPage; ~LPxVYhK
} ~\tI9L?|A
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/** r]eeKV,{p
* @param everyPage >9c$2d|>
* The everyPage to set. ]!J 6S.@#+
*/ Y:C7S~
publicvoid setEveryPage(int everyPage){ OKfJ
this.everyPage = everyPage; 8~?3: IZ
} !oeu
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/** orn9;|8q
* @return oxE'u<
* Returns the hasNextPage. ;crQ7}k
*/ ;bVC7D~~4w
publicboolean getHasNextPage(){ n(.y_NEgV!
return hasNextPage; ]gYnw;W$
} 2Yt#%bj7^
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/** W
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* @param hasNextPage W O W4c&
* The hasNextPage to set. 3jPua)=p
*/ 5T;M,w6DV
publicvoid setHasNextPage(boolean hasNextPage){ ;cl\$TDL
this.hasNextPage = hasNextPage; Uw^`_\si
} Zrp`91&I
/5Wy)-
/** a'w~7y!}
* @return R6HMi#eF
* Returns the hasPrePage.
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*/ I%^Ks$<"
publicboolean getHasPrePage(){ ^"\ jIP
return hasPrePage; vz:P2TkM
} zVe@`gc
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/** }l&Uh&B`
* @param hasPrePage b7g\wnV8z
* The hasPrePage to set. yfeX=h
*/ )n 1b
publicvoid setHasPrePage(boolean hasPrePage){ Ddde,WJA
this.hasPrePage = hasPrePage; ~H/|J^ J
} oK&LYlU
j<>|Hi
#`
/** ^,')1r,
* @return Returns the totalPage. %pgie"k
* tLe!_p)
*/ Q=J"#EFs
publicint getTotalPage(){ !7!xJ&/V
return totalPage; 8;;!2>N
} 1a3rA
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/** f>ohu^bd
* @param totalPage qd"1KzQWO
* The totalPage to set. Ar4E $\W
*/ LAeJz_9U
publicvoid setTotalPage(int totalPage){ g1VdP[Y#
this.totalPage = totalPage; qEr2Y/:i"
} r
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q}e"E
cr
} [Hz_x(t26
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fv_}7t7
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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 zu'Uau
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个PageUtil,负责对Page对象进行构造: j*>+^g\Q6
java代码: 3}=r.\]U
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~C=I{qzF+
/*Created on 2005-4-14*/ 1C\OL!@L
package org.flyware.util.page; D_
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import org.apache.commons.logging.Log; \UM9cAX`
import org.apache.commons.logging.LogFactory; t
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/** IY6DZP
* @author Joa 24PEt%2
* ,80qwN,
*/ \"B?'Ep;
publicclass PageUtil { 7l> |G,[c
D].!u{##
privatestaticfinal Log logger = LogFactory.getLog T:q_1W?h]
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(PageUtil.class); Wr Ht
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/** }#'wy
* Use the origin page to create a new page Kk1 591'
* @param page HQ~`ha.
* @param totalRecords XL@i/5C[
* @return ~K}iVX
*/ $2qZds[
publicstatic Page createPage(Page page, int R06L4,/b
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totalRecords){ ,#[0As29u
return createPage(page.getEveryPage(), '^ b B+
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page.getCurrentPage(), totalRecords); 5vs~8|aRo
} nf&PDv1
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/** C,7d
* the basic page utils not including exception Z"PPXv-<jY
0X@!i3eu
handler b/'{6zn
* @param everyPage WZO8|hY
* @param currentPage q`z/ S>
* @param totalRecords V(_OyxeC{2
* @return page `s5<PCq
*/ X.hU23w
publicstatic Page createPage(int everyPage, int H,`F%G#!`q
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currentPage, int totalRecords){ e5G)83[=
everyPage = getEveryPage(everyPage); yG\^PD
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, f =@'F=
51j5AbFQ"
currentPage); )QYg[<e6
int totalPage = getTotalPage(everyPage, )[RLCZ
koOkm:(,
totalRecords); \J[m4tw^
boolean hasNextPage = hasNextPage(currentPage, r/zuo6"5
0Jz H dz
totalPage); c} )U:?6
boolean hasPrePage = hasPrePage(currentPage); 3/c3e{,!
85CH%
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returnnew Page(hasPrePage, hasNextPage, li'h&!|]
everyPage, totalPage, ~_opU(;f
currentPage, aX`"V/
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beginIndex); {<&i4;
} {y)O?9q
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privatestaticint getEveryPage(int everyPage){ Z`x|\jI
return everyPage == 0 ? 10 : everyPage; Cbu/7z
} !>QS746S@
fB^h2
privatestaticint getCurrentPage(int currentPage){ xIu#
return currentPage == 0 ? 1 : currentPage; -!MrG68
}
Fj Rt'
/(IV+
privatestaticint getBeginIndex(int everyPage, int J1OZG6|e
G8=2=/ !
currentPage){ 3FRz&FS:j
return(currentPage - 1) * everyPage; ro|mWP0
} -]""Jl^
Zjis0a]v~k
privatestaticint getTotalPage(int everyPage, int MMlryn||1
kQ~2mU
totalRecords){ {!!df.h
int totalPage = 0; E;!pK9wL|
$A~UA
if(totalRecords % everyPage == 0) zVN/|[KP4
totalPage = totalRecords / everyPage; DfYOGs]@
else 3ARvSz@5
totalPage = totalRecords / everyPage + 1 ; Gk_%WY*
Z]?Tx2|7
return totalPage; pde,@0(Fa
} q#LB 2M
>[t0a"
privatestaticboolean hasPrePage(int currentPage){ ^u'hl$`^
return currentPage == 1 ? false : true; W0e+yIaR
} $VEG1]/svp
_|<kKfd?
privatestaticboolean hasNextPage(int currentPage, l-s%3E3
PPoQNW
int totalPage){ EWOS6Yg7
return currentPage == totalPage || totalPage == p7 s#j
kc*zP=
0 ? false : true; 'Cv,:Q
} ]0N'Wtbn
\8j5b+
!ieMhJ5r
} o95)-Wb
i%BrnjX
+c)"p4m
`=m[(CLb
u#(&
R"6
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 6cR}Mm9Hx3
0IZaf%zYc
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 A:|dY^,:?*
c:#<g/-{wM
做法如下: t][U`1>i
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 zED#+-7
yx5F]Z<M2
的信息,和一个结果集List: b-*3]gB
java代码: 5mzOr4*0
&UzeNL"]
=BD} +(3
/*Created on 2005-6-13*/ %=p:\+`VI
package com.adt.bo; s
P=$>@3
BR&T,x/d
import java.util.List; ]5(T{
JFAmND;+
import org.flyware.util.page.Page; LDg"s0n#
.'`7JU#{
/** R Lnsy,
* @author Joa <//82j+px
*/ eKRslMa
publicclass Result { mL5 Nu+#
j
/d?c5
private Page page; (PVK|Q55y
vjo@aY.x
private List content; j^4KczJl
zk6al$3R
/** RYhaQ&1i
* The default constructor )"( ojh
*/ 8aDSRfv*
public Result(){ hz:^3F`>/&
super(); $'Pn(eZHGv
} 0!4;."S
G.j R
/** S8=Am7D]1
* The constructor using fields $ghAC
* m(2(Caz{
* @param page 6d4e~F
* @param content Om%HrT
*/ c}XuzgSY
public Result(Page page, List content){ 2bJqZ,@
this.page = page; Lj]I7ICNh
this.content = content; K&L9Ue
} NxOiT#YH
euxkw]`h6
/** J#k3iE}
* @return Returns the content. '(ZJsw
*/
ywQ>T+
publicList getContent(){ iJ8 5okv'
return content; hMcSB8 ?
} L&D+0p^lI
!yUn|v>&p
/** eA4dDKX+
* @return Returns the page. kzky{0yKk=
*/ N+)gYb6h
public Page getPage(){ 8S8^sP
return page; #=}dv8
} @ve4rc/LI
`zRE $O
/** 1\'?.
* @param content %_kXC~hH_
* The content to set. ] ^f7s36
*/ .2K4<UOAbm
public void setContent(List content){ s=[Tm}[
this.content = content; E$u9Jbe
} $`KddW0_
^Vbx9UN/
/** p3m!Iota
* @param page dwH8Zg$B
* The page to set. 3CKd[=-Z
*/ dz3KBiq
publicvoid setPage(Page page){ fX:)mLnO/
this.page = page; 2yB@)?V/
} ( M > C
} 4$5d*7
/mi9q
r>>4)<C7J
^)JUl!5j]C
<yoCW?#
2. 编写业务逻辑接口,并实现它(UserManager, S!LLC{
]JQ+*ZYUE
UserManagerImpl) )td?t.4
java代码: #NoY}*
AX`>y@I
8+7n"6GY2/
/*Created on 2005-7-15*/ tQrF A2F
package com.adt.service; .C6wsmQ
@Cnn8Y&'
import net.sf.hibernate.HibernateException; {OH
@z!+d
!Q/%N#
import org.flyware.util.page.Page; s8r|48I#;
G{ |0}
import com.adt.bo.Result; *A^j>lV
S=
NG J0
/** 31y>/*}
* @author Joa x4_xl
.
*/ >5O#_?
publicinterface UserManager { zeC@!,lH
Z(|@C(IL0\
public Result listUser(Page page)throws mQbpv'N
a/4!zT
HibernateException; uVSc1MS1
0h3-;%
} tRUGgf`
?(t{VdZSzQ
_mEW]9Sp
he
vM'"|4
z1K}] z%
java代码: a>05Yxw
:
\{>+!`w
=7e|e6
/*Created on 2005-7-15*/ 4 !q4WQ ;
package com.adt.service.impl; ?cZ#0U
0P+B-K>n
import java.util.List; l[,RA?i
{
`<?{%ja
import net.sf.hibernate.HibernateException; (TX\vI&
+zl2|'
import org.flyware.util.page.Page; ?k 4|;DD
import org.flyware.util.page.PageUtil; V(?PKb-w)
?Z1&ju,Hd-
import com.adt.bo.Result; u|G&CV#r
import com.adt.dao.UserDAO; vqeWt[W
v
import com.adt.exception.ObjectNotFoundException; XEUy,>mR
import com.adt.service.UserManager; F2N)|C<
sy\w ^]
/** wU"0@^k]<
* @author Joa hoj('P2a#n
*/ |}?o=bO
publicclass UserManagerImpl implements UserManager { Lddk:u&J
t+H=%{z
private UserDAO userDAO; \{GBaMwG~
vMlT
/** g?9IS,Gp
* @param userDAO The userDAO to set. +,g"8&>
*/ +WH|nV~lQ
publicvoid setUserDAO(UserDAO userDAO){ Bd8{25{c
this.userDAO = userDAO; L@&(>
} Qf'%".*=~8
+Cf
/* (non-Javadoc) pBb fU2p
* @see com.adt.service.UserManager#listUser +L]$M)*0&
`Z'h[-2`
(org.flyware.util.page.Page) 6-+q3#e
*/ liuw!
public Result listUser(Page page)throws gZg5On
xMpQPTte
HibernateException, ObjectNotFoundException { @:ojt$
int totalRecords = userDAO.getUserCount(); $;V?xZm[
if(totalRecords == 0) iPuX
throw new ObjectNotFoundException wuV*!oef o
^z^zsNx
("userNotExist"); \-h%z%{R
page = PageUtil.createPage(page, totalRecords); =dp(+7Va
List users = userDAO.getUserByPage(page); $oo`]R_
returnnew Result(page, users); {!/ha$(
} </jzM?i
AWG;G+
} Dus [N<
w
;Pd nE~
~CRd0T[^
Ocp`6Fj
*URBx"5XZ
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 g2|qGfl{C
oR1HJ2>Z1
询,接下来编写UserDAO的代码: nl\l7/}6
3. UserDAO 和 UserDAOImpl: |GLh|hr
java代码: z5_#]:o&
]E:K8E
y+"6Y14
/*Created on 2005-7-15*/ {~y,.[Ga
package com.adt.dao; knS(\51A
V:Lq>rs#
import java.util.List; .:U`4->E
+!F+mV9
import org.flyware.util.page.Page; ~TvKMW6/#
.IkQo`_s:
import net.sf.hibernate.HibernateException; A7c*qBt
CwL8-z0 Jn
/** )/{zTg8$?/
* @author Joa mV'XH
*/ 6oA2"!u^w
publicinterface UserDAO extends BaseDAO { =mQdM]A)2
KccI Yn~
publicList getUserByName(String name)throws Gp.XTz#=
":meys6t#
HibernateException; !C3ozZ<
dR|*VT\
publicint getUserCount()throws HibernateException; >DSD1i+N
9ZVzIv(
publicList getUserByPage(Page page)throws t"Tv(W?_
/T\'&s3D+
HibernateException; '&+5L.
"WfVZBWG$
} 5%#V>|@e#
nPRv.h
xJ(}?0h-X
Q?xCb
RO!em~{D*
java代码: pcC/$5FQ
hziPHuK9,
vvwQ/iJO4Q
/*Created on 2005-7-15*/ \\d!z-NOk?
package com.adt.dao.impl; 0tS<
/G8
j0q:i}/U,
import java.util.List; ~\]lMsk+
QMQ\y8E
import org.flyware.util.page.Page; ^NB\[ &
0YA
import net.sf.hibernate.HibernateException; _@L{]6P%V
import net.sf.hibernate.Query; =6Q\78b
p*5QV
import com.adt.dao.UserDAO; Muay6b?
cME|Lg(J$
/** {^V9?^?d (
* @author Joa vAt]N)R
*/ #KgDOCQH
public class UserDAOImpl extends BaseDAOHibernateImpl $)v`roDD.
y3Qb2l
implements UserDAO { #O,;3S
Tg yY 9
/* (non-Javadoc) oksAQnQe
* @see com.adt.dao.UserDAO#getUserByName {Lg]chJq?
r>,s-T!7
(java.lang.String) EN-;@P9;C
*/ $VNj0i. Pr
publicList getUserByName(String name)throws Q^ }Ib[
Em]2K:
HibernateException { 76eF6N+%}t
String querySentence = "FROM user in class &G$K.q
MJugno
com.adt.po.User WHERE user.name=:name"; T8W;Lb9hQ
Query query = getSession().createQuery
i38`2
+aZcA#%
(querySentence); ?8!\V NC.
query.setParameter("name", name); w<SFs#Z
return query.list(); PdqyNn=
} vJ9IDc|[
xRbtiFk9H
/* (non-Javadoc) z]HaE|j}S
* @see com.adt.dao.UserDAO#getUserCount() 1{-yF :A
*/ 3Q!)bMv \
publicint getUserCount()throws HibernateException { 36MNaQt'e
int count = 0; %?m_;iv
String querySentence = "SELECT count(*) FROM 6mmc{kw'
pg.BOz\'q
user in class com.adt.po.User"; K};~A?ET,h
Query query = getSession().createQuery 1"S~#
P^^WViVX
(querySentence); {wh, "Ok_
count = ((Integer)query.iterate().next GQ\;f
gaWJzK
Yc_
()).intValue(); i)q8p
return count; E(!b_C&
} [=]LR9c4
,B1~6y\b
/* (non-Javadoc) ?bGk%jjHXM
* @see com.adt.dao.UserDAO#getUserByPage h|%a}])G)
zGtv(gwk
(org.flyware.util.page.Page) ht_'GBS)
*/ ZtGtJV"H
publicList getUserByPage(Page page)throws Vb,'VN%
x(7Q5Uk\
HibernateException { iI Dun Ih
String querySentence = "FROM user in class R q`j|tY
'0<9+A#
com.adt.po.User"; D9JHx+Xf>
Query query = getSession().createQuery s<{) X$
x5R|,bY
(querySentence); pEq }b+-
query.setFirstResult(page.getBeginIndex()) 2= zw!
.setMaxResults(page.getEveryPage()); \p#_D|s/Ep
return query.list(); 3c+ps;nh
} 6,~]2H'zq
LnPG+<
} (*Z:ByA
a FL;E
6t4Khiwx
]Jo}F@\g
v}TFM
至此,一个完整的分页程序完成。前台的只需要调用 6 IRa$h>H
^$s&bH'8
userManager.listUser(page)即可得到一个Page对象和结果集对象 HcM/
jI%glO'2
的综合体,而传入的参数page对象则可以由前台传入,如果用 [ d`m)MW-
5c$\DZ(
webwork,甚至可以直接在配置文件中指定。 "KgNMNep
uyvjo)T
下面给出一个webwork调用示例: 9V|)3GF
java代码: PR7B
Cxm
06e dVIRr
~l}\K10L*
/*Created on 2005-6-17*/ >qZl
s'
package com.adt.action.user; o,RiAtdk
4UHviuOo8
import java.util.List; .'NTy
R
S$
k=70H
import org.apache.commons.logging.Log; <m~{60{
import org.apache.commons.logging.LogFactory; zKT4j1h
import org.flyware.util.page.Page; [qU`}S2
Dt\rrN:v
import com.adt.bo.Result; beB3*o
import com.adt.service.UserService; [\rzXE
import com.opensymphony.xwork.Action; ]3~u @6
Y
h53Z"a
/** J-qUJX~4c
* @author Joa S6Y:Z0
*/ $\q.Zb
publicclass ListUser implementsAction{ ueEf>0
DFvGc`O4
privatestaticfinal Log logger = LogFactory.getLog "^)GnK +-
b[J0+l\!"
(ListUser.class); /=g/{&3[a>
Yl=-j
private UserService userService; >[;L.
8nwps(3
private Page page; r7FJqd
TfHL'u9B
privateList users; 4s@Tn>%SP
'Fql;&U
>
/* /vC!__K9:
* (non-Javadoc) V9jxmu F,
* L1f=90
* @see com.opensymphony.xwork.Action#execute() X#HH7V>
*/ ~n!&~
publicString execute()throwsException{ 7$x%A&]
Result result = userService.listUser(page); o]]sm}3N
page = result.getPage(); ;y-:)7J
users = result.getContent(); 56Z
return SUCCESS; 5~ZzQG
} y06xl:iQwF
8nWPt!U:
/** O3mw5<%15
* @return Returns the page. ,.h@tN<C
*/ QN|=/c<U
public Page getPage(){ 'Lw8l `7
return page; Gpi_p
} 9hssIZO
e7b MK<:r
/** }h1eB~6M
* @return Returns the users. S^D7}
*/ OCq5}%yU&i
publicList getUsers(){ "Q:h[) a
return users; *K|ah:(r1\
} Z}t^i^u
D[}^G5
/** 9|[uie
* @param page ^do6?e`?-
* The page to set. 74N3wi5B
*/ LAY:R{vI
publicvoid setPage(Page page){ M<*WC{
this.page = page; 0igB pHS
} 0TSB<,9a[
aEh9za
/** t`{T:Tjc
* @param users ``I[1cC
* The users to set. #
5U1F[
*/ FvYciU!
publicvoid setUsers(List users){ ;<thEWH;Y
this.users = users; mwyB~,[d+W
} F#M(#!)Y"
6/?onEL9_
/** &:IcwD&
* @param userService Sk1t~
* The userService to set. , ,ng]&%i
*/ $IjI{%
publicvoid setUserService(UserService userService){ {
PJ>gX$
this.userService = userService; p\F%Nj,
} 8D,*_p
} EU>`$M&w-
;,e16^\' &
B /w&Lo
F?05+
t*-cX
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, x#N_h0[i
yjMN>L'
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 deVnAu =
y+w,j]
么只需要: {j;` wN
java代码: |2@*?o"ll
; :q
m4m|?
<?xml version="1.0"?> 4OQ,|Wm4G
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork h.F=Fhx/1
k4hk*
0Jq
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +xU( {/
l"1D'Hk
1.0.dtd"> Ox&G
[
FMI1[|:;
<xwork> lw[c+F7
FKu8R%9xn%
<package name="user" extends="webwork- ed}#S~4q
Y&8,f|{R
interceptors"> VN`fZ5*d~
;RX u}pd
<!-- The default interceptor stack name v=0G&x=/
3Jlap=]68S
--> ]d@>vzCO
<default-interceptor-ref 6hv.;n};
Bt(<Xj D
name="myDefaultWebStack"/> h9CTcWGt
^V#,iO9.-
<action name="listUser" uC#@qpzy
/]5*;kO`
class="com.adt.action.user.ListUser"> M<n'ZDK`W
<param {srxc4R`
\`xlD&F@U
name="page.everyPage">10</param> -fmJkI
<result 7>BfHb
w4Df?)Z
name="success">/user/user_list.jsp</result> G$MEVfd"
</action> 3Cc#{X-+
D\9-/p
</package> UO@K:n
VZI!rFac
</xwork> 3B
'j?+A
fz :(mZ%
p^k0Rad
)"6-7ii7(f
0
}od Q#
QAp]cE1ew
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 3N|z^6`#
v[^8_y}A`
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。 PWiUW{7z
JHvev,#4
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ^PezV5(
y^`JWs,
qJrKt=CE
$=N?[h&4
/B~[,ES@1
我写的一个用于分页的类,用了泛型了,hoho J:glJ'4E
,r;xH}tbi
java代码: 6{HCF-cQd
u"*DI=pwb
Wu/#}Bw#
package com.intokr.util; #IM.7`I
,:A;4
import java.util.List; S* O .
?
9tPRQM7
/** !Vw1w1
* 用于分页的类<br> ChG7>4:\
* 可以用于传递查询的结果也可以用于传送查询的参数<br> -HQbvXAS
* {DQ%fneN4
* @version 0.01 8mKp PwG0
* @author cheng o5?Y
*/ [%N?D#;
public class Paginator<E> { &tAYF_}
privateint count = 0; // 总记录数 -R:_o1"
privateint p = 1; // 页编号 cS9jGD92
privateint num = 20; // 每页的记录数 @|DQZt
privateList<E> results = null; // 结果 Coe/ 4!$M
mQ"uG?NE
/** pLtw|S'4
* 结果总数 2icQ (H;
*/ e@W+ehx"
publicint getCount(){ m)Kg6/MV.
return count; x'I!f? / &
} </`\3t
?}4,s7PR
publicvoid setCount(int count){ ebQgk
Y=
this.count = count; :1>?:3,`
} @
gWd
ngl +`|u
/** d9M[]{
* 本结果所在的页码,从1开始 c:Nm!+5_(
* 8$
u"92
* @return Returns the pageNo. h7UNmwj
*/ ~EPVu
publicint getP(){ x~!|F5JbM
return p; %ERcFI]G
} ;: 2U}p^-
kY~4AH
/** 5z!$=SFz
* if(p<=0) p=1 XH$r(@Z\7
* YiDO V)
* @param p '6 F-%
*/ =x\`yxsG
publicvoid setP(int p){ 7*{f*({
if(p <= 0) L!If~6oD(
p = 1; ZhA_d#qH
this.p = p; sjg`4^!wDD
} |
:-i[G?n
F`QViZ'n>#
/** nOGTeKjEJ
* 每页记录数量 jRS{7rx%MH
*/ `Zm6e!dH-
publicint getNum(){ 1^}I?PbqV
return num; ^U*y*l$
} *(?Wzanh
3uqhYT;
/** Ww2@!ng
* if(num<1) num=1 _xp8*2~-
*/ Mz(Vf1pi%
publicvoid setNum(int num){ ?1SsF>|
if(num < 1) rm,`M
num = 1; W8^m-B&
this.num = num; zl|z4j'Irc
} yijP
ro{!X, _$,
/** +1!iwmch>
* 获得总页数 Kf[d@L
*/ rR> X<
publicint getPageNum(){ S=(O6+U
return(count - 1) / num + 1; o[Jzx2A<
} Go)$LC0Mi
\xkKgI/
/** W-=6:y#A
* 获得本页的开始编号,为 (p-1)*num+1 eyCZ[SC
*/
J, 9NVw$
publicint getStart(){ ##7y|AwK
return(p - 1) * num + 1; GkIY2PD
} N7+L@CC6T
6QX m]<
/** `OBzOM
* @return Returns the results. kt/,& oKI
*/ s{Z)<n03
publicList<E> getResults(){ MY^{[#Q
return results; F~mIV;BP
} {arqcILr
ZD]1C~)
public void setResults(List<E> results){ "La;$7ds
this.results = results; r!mRUw'u
} ?l0Qi
YA4 D?'
public String toString(){ *j%x
StringBuilder buff = new StringBuilder mH'~pR>t
8b2 =n
();
}X&rJV
buff.append("{"); <-umeY"n>
buff.append("count:").append(count); Wh)D_
buff.append(",p:").append(p); d#g))f;
buff.append(",nump:").append(num); w7V\_^&Id
buff.append(",results:").append 7Q}pKq]P
M3pE$KT0x
(results); u5(8k_7
buff.append("}"); <xOX+D
return buff.toString(); -zR<m
} +WH\,E
&]nx^C8V;
} %;,fI'M
h Jb2y`,q
z%82Vt!a5