Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .Cl:eu,]
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3!oi +_
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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 ^pF&`2eD
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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 [dIXR
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分页支持类: H0`]V6+<f
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java代码: 8sTp`}54J
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package com.javaeye.common.util; K<qk.~
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import java.util.List; 27O|).yKX
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publicclass PaginationSupport { jun_QiU:2
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publicfinalstaticint PAGESIZE = 30; $ig0j`
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privateint pageSize = PAGESIZE; J1sv[$9
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privateList items; $r8 ^0ZRr
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privateint totalCount; wFsyD3
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privateint[] indexes = newint[0]; Q)"Nu.m
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privateint startIndex = 0; c[4i9I3v
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public PaginationSupport(List items, int <[\`qX
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totalCount){ fS [,vPl
setPageSize(PAGESIZE); kG@@ot" n
setTotalCount(totalCount); *|>d
setItems(items); dDGgvi|[Mz
setStartIndex(0); jW3!6*93
} Xr$J9*Jk-
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public PaginationSupport(List items, int 9-
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totalCount, int startIndex){ B9$jSD
setPageSize(PAGESIZE); ()Y4v
setTotalCount(totalCount); TKY*`?ct
setItems(items); ,t9^j3Ixg
setStartIndex(startIndex); KB`!Sj\
} q6SXWT'Sa
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public PaginationSupport(List items, int I E&!YP(U(
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totalCount, int pageSize, int startIndex){ )d1_Wm#B
setPageSize(pageSize); ,PuL{%PXu
setTotalCount(totalCount); r1.nTO%
setItems(items); zHL@i0>^
setStartIndex(startIndex); uK$9Ll{lk
} q[`]D7W
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publicList getItems(){ BJB^m|b)
return items; g -HN
} P+PR<ZoI{f
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publicvoid setItems(List items){ K/b_22]CC
this.items = items;
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} t.&Od;\[/
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publicint getPageSize(){ q<[_T
return pageSize; FsV'Cu@!U
} 8U>B~9:JO
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publicvoid setPageSize(int pageSize){ KJ=6 n%6
this.pageSize = pageSize; jN>{'TqW4
} D@|W<i-
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publicint getTotalCount(){ %Bn?n{/
return totalCount; V |/NB
} ') gi%
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publicvoid setTotalCount(int totalCount){ 0]=i}wL 8
if(totalCount > 0){ V9(@Y
this.totalCount = totalCount; e2ilB),
int count = totalCount / feNdMR7eM
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pageSize; pUq1|)g
if(totalCount % pageSize > 0) F\AX:
count++; 04'~ta(t
indexes = newint[count]; :GW&O /Yo
for(int i = 0; i < count; i++){ 9h%?QC
indexes = pageSize * 2eC(Ijq[a
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} 1~ t{aLPz
}else{ X
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this.totalCount = 0; UkHY[M7;
} >O?U=OeD
} J?}WQLVP'
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publicint[] getIndexes(){ psC
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return indexes; J9Ou+6 u(
} {g~bQ2wDC
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publicvoid setIndexes(int[] indexes){ :ORR_f`>
this.indexes = indexes; }kK[S|XVO
} 4e;yG>
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publicint getStartIndex(){ QgD g}\P
return startIndex; ]%Nlv(
} H_Kj7(=&>
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publicvoid setStartIndex(int startIndex){ Qb; d:@9
if(totalCount <= 0) M=*bh5t%]
this.startIndex = 0; xIGfM>uq
elseif(startIndex >= totalCount) ''^Y>k
this.startIndex = indexes "/6:6`J
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[indexes.length - 1]; Kryo}
elseif(startIndex < 0) ZA9sTc[
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this.startIndex = 0; )d-.M
else{ O Xi@c;F
this.startIndex = indexes sf| ke9-3
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[startIndex / pageSize]; ND,Kldji
} G0{H5_h
} {}m PEd b
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publicint getNextIndex(){ G #T<`>T
int nextIndex = getStartIndex() + o/
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pageSize; he -Ji
if(nextIndex >= totalCount) +"}=d3E6
return getStartIndex(); eo!zW
else F3lw@b3])
return nextIndex; xc:!cA{V
} TtDg*kZ
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publicint getPreviousIndex(){ u!U"N*Y"
int previousIndex = getStartIndex() - KkMay
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pageSize; (ihP`k-.
if(previousIndex < 0) <{:
return0; W85@v2b
else Dbaf0
return previousIndex; ow;R$5G
} e{9jn>\,a
j ! NO|&k
} -/dEsgO
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抽象业务类 $]&(7@'qo
java代码: NLe}Jqp
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/** MfBdNdox7
* Created on 2005-7-12 Y'3}G<'%
*/ '[(nmx'yVJ
package com.javaeye.common.business; M4LktR-[
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import java.io.Serializable; }Y1>(U
import java.util.List; 25|8nfeC5
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import org.hibernate.Criteria; u%d K ig
import org.hibernate.HibernateException; $7Mtt.d6
import org.hibernate.Session; >71&]/Rv
import org.hibernate.criterion.DetachedCriteria; PS" .R_"
import org.hibernate.criterion.Projections; wFIh6[3
import TfZ6F8|B
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org.springframework.orm.hibernate3.HibernateCallback; JH]K/sC>
import |m?vVLq
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org.springframework.orm.hibernate3.support.HibernateDaoS q 'a
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upport; qG9+/u)\
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import com.javaeye.common.util.PaginationSupport; 7W9d6i)
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public abstract class AbstractManager extends xaKst
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HibernateDaoSupport { i~{
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privateboolean cacheQueries = false; yISD/
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privateString queryCacheRegion; E}Xka1 Bn
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publicvoid setCacheQueries(boolean =vh8T\
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cacheQueries){ n1:v HBM@\
this.cacheQueries = cacheQueries; AdoZs8Q
} ;}.Kb
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publicvoid setQueryCacheRegion(String l t]B#, '
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queryCacheRegion){ f|a DTWF
this.queryCacheRegion = Y"eEkT\
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queryCacheRegion; #S+Z$DQD
}
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publicvoid save(finalObject entity){ 6=PiVwI
getHibernateTemplate().save(entity); 4DO/rtkVq
} VAYb=4lt
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publicvoid persist(finalObject entity){ xwzT#DXGJ
getHibernateTemplate().save(entity); Rh] P8
} {R&ZqEo'D
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publicvoid update(finalObject entity){ a%J6f$A#
getHibernateTemplate().update(entity); vU/ D7
} qG>DTKIU
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publicvoid delete(finalObject entity){ jlKGXD)Q[
getHibernateTemplate().delete(entity); U06o;s(
} EH+~].PJd
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publicObject load(finalClass entity, m<3v)R[>
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finalSerializable id){ 5y_"
return getHibernateTemplate().load 2N6=8Xy5K
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(entity, id); .)8
} LEc8NQs
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publicObject get(finalClass entity, j[S`^2
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finalSerializable id){ ?:|YGLaB
return getHibernateTemplate().get U?U(;nSR\A
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(entity, id); `h;}3r#R{
} n2;9geq+
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publicList findAll(finalClass entity){ Plz-7fy33
return getHibernateTemplate().find("from qCJ=Z
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" + entity.getName()); TIRHT`"i
} .~dEUt/|)
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publicList findByNamedQuery(finalString U
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namedQuery){ 135Par5v
return getHibernateTemplate U
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().findByNamedQuery(namedQuery); 'rV2Bt,
} 6hbEO-(
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publicList findByNamedQuery(finalString query, ?2~U2Ir]:
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finalObject parameter){ =O^7TrM
return getHibernateTemplate cy:;)E>/
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().findByNamedQuery(query, parameter); V}`M<A6:
} *t=i
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publicList findByNamedQuery(finalString query, 7L{li-crI
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finalObject[] parameters){ \3 KfD'L
return getHibernateTemplate c57b f
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().findByNamedQuery(query, parameters); >7FSH"8[,
} oBUh]sR{.
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publicList find(finalString query){ ]b\WaS8I
return getHibernateTemplate().find Rk[8Bd?
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(query); *7vue"I*Z
} ^X;JT=r
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publicList find(finalString query, finalObject `Wwh`]#"~d
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parameter){ u@"o[e':
return getHibernateTemplate().find ty;o&w$
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(query, parameter);
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} KS>Fl->
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public PaginationSupport findPageByCriteria ]*h&hsS0
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(final DetachedCriteria detachedCriteria){ ht$ WF
return findPageByCriteria D1~^\)*
3 \9][S-B
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 0kz7 >v
} f8F1~q
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public PaginationSupport findPageByCriteria S%P3ek>3
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(final DetachedCriteria detachedCriteria, finalint cl#OvQ
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startIndex){ <W9) Bq4
return findPageByCriteria 6g5]=Q@U:
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(detachedCriteria, PaginationSupport.PAGESIZE, v @_?iC"`
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startIndex); 4]M =q{
} HO G=c!b
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public PaginationSupport findPageByCriteria t;~-_{
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(final DetachedCriteria detachedCriteria, finalint Bzwx0c2VY8
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pageSize, zVn* !c
finalint startIndex){ GHqBnE{B
return(PaginationSupport) vzQyE0T/
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getHibernateTemplate().execute(new HibernateCallback(){ Hm<M@M$aG
publicObject doInHibernate -<12~HKK::
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(Session session)throws HibernateException { aSxG|OkKy
Criteria criteria = Ny[s+2?
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detachedCriteria.getExecutableCriteria(session); y>&VtN{E
int totalCount = )<tzm'Rc
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((Integer) criteria.setProjection(Projections.rowCount !4!S{#<q
6#/LyzZq|
()).uniqueResult()).intValue(); 3 pHn_R
criteria.setProjection U
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(null); \_)02ZT:
List items = ]r]+yM|
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criteria.setFirstResult(startIndex).setMaxResults Ed8U;U b
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(pageSize).list(); >J?jr&i
PaginationSupport ps = Rb yF#[}
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new PaginationSupport(items, totalCount, pageSize, Ig='a"%
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startIndex); CD$u=E
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return ps; /7S-|%1
} oa?!50d
}, true); x*k65WO\
} Pi^ECSzQu[
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public List findAllByCriteria(final FL5ibg
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DetachedCriteria detachedCriteria){ ye56-T
return(List) getHibernateTemplate Kn3YI9
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().execute(new HibernateCallback(){ R'jUS7]Y
publicObject doInHibernate o$^O<z L
)jp{*?^\
(Session session)throws HibernateException { h,Y{t?Of
Criteria criteria = k,yc>3P;U
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detachedCriteria.getExecutableCriteria(session); /[p?_EX@
return criteria.list(); #%9oQ6nO
} *tIdp`xT/T
}, true); m[//_TFf]
} -%7Jj;yA
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public int getCountByCriteria(final 0 m)-7@
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DetachedCriteria detachedCriteria){ A?^A*e
Integer count = (Integer) :%+^}
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getHibernateTemplate().execute(new HibernateCallback(){ `bBfNI?3d*
publicObject doInHibernate mRg ,A\
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(Session session)throws HibernateException { $l0eI
Criteria criteria = 58a)&s[+
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detachedCriteria.getExecutableCriteria(session); H'j_<R N
return 401/33yBJ
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criteria.setProjection(Projections.rowCount d;*OO xQV
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()).uniqueResult(); 5#N"WHz!
} v ^ FV
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}, true); O?+tY
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return count.intValue(); mgJ]@s}9
} ;C7BoHB9
} P':]A{<Z
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用户在web层构造查询条件detachedCriteria,和可选的 *Xf[b)FR
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _>Pe]3
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PaginationSupport的实例ps。 sM);gI14
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ps.getItems()得到已分页好的结果集 wz|Q%.%?[
ps.getIndexes()得到分页索引的数组 =DQd PA\K
ps.getTotalCount()得到总结果数 ly[\mGr
ps.getStartIndex()当前分页索引 w[J
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ps.getNextIndex()下一页索引 p4<M|1Z&
ps.getPreviousIndex()上一页索引 n9mM5H47
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 6@,'m
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 6cgpg+-a
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一下代码重构了。 *cI6&;y
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我把原本我的做法也提供出来供大家讨论吧: m;$F@JJ
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首先,为了实现分页查询,我封装了一个Page类: 6@ (k8<3
java代码: hhh: rmEZl
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/*Created on 2005-4-14*/ _z"ci$[
package org.flyware.util.page;
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/** Fh3Dc 83~
* @author Joa f6aT[Nw<
* 56j/w[&8
*/ OJC*|kN-#^
publicclass Page { E-7a`S
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/** imply if the page has previous page */ X<@y*?D9D
privateboolean hasPrePage; cr=FMfhB
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/** imply if the page has next page */
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privateboolean hasNextPage; Cs~\FI1wR
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/** the number of every page */ aLyhxmn ^)
privateint everyPage; d
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/** the total page number */ HnKF#<
privateint totalPage; >R'VY "\
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/** the number of current page */ 9DP75 ti
privateint currentPage; wYS
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/** the begin index of the records by the current |WwFE|<
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query */ \qK}(xq[
privateint beginIndex; xhVq
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/** The default constructor */ OrKT~JQVC&
public Page(){ 6jy n,GU
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} /w0v5X7
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/** construct the page by everyPage {0Ol/N;|D
* @param everyPage ~%!U,)-
* */ GXvo't@N
public Page(int everyPage){ f'?6D+Yw~
this.everyPage = everyPage; tV}ajs
} (HX [bG`
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/** The whole constructor */ _-yF9g"I
public Page(boolean hasPrePage, boolean hasNextPage, Hh'14n&W
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int everyPage, int totalPage, 77bZ
int currentPage, int beginIndex){ w]P7!t
this.hasPrePage = hasPrePage; NtP.)
this.hasNextPage = hasNextPage; +/UXy2VRt$
this.everyPage = everyPage; Le$u$ulS
this.totalPage = totalPage; KA*l6`(
this.currentPage = currentPage; 3~1lVU:
this.beginIndex = beginIndex; #+DmH
} (A<sFw?
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/** 2KNKdV3NK
* @return HBf8!\0|/
* Returns the beginIndex. ]bU'G$Qm&s
*/ x)qHeS
publicint getBeginIndex(){ \5pAG
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return beginIndex; iJj?~\zp
} sZP3xh[B
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/** `F`'b)
* @param beginIndex Vh[o[ U
* The beginIndex to set. y2hFUq
*/ hm} :Me$[)
publicvoid setBeginIndex(int beginIndex){ "jN-Yd,z
this.beginIndex = beginIndex; $(mdz)Cfy
} =&g}Y
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/** v]Q_
* @return (,9cCnvmYU
* Returns the currentPage. k)GuMw
*/ \fFy$
publicint getCurrentPage(){ iI Nu`>I
return currentPage; `h{mj|~
} bqwW9D(
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/** "Ohpb!J9
* @param currentPage x]01j4HJ
* The currentPage to set. 48NXj\L[y
*/ 6!D
publicvoid setCurrentPage(int currentPage){ oHFDg?Z`
this.currentPage = currentPage; Z.OrHg1
} .p*D[o2 9
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/** $m0x8<7nu
* @return 6XCX#4'i%
* Returns the everyPage. 7D_kkhN
*/ &"6ktKrIg
publicint getEveryPage(){ )KhVUFS1
return everyPage; K1{nxw!`
} 'oeg[
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/** eeTaF!W
* @param everyPage ~I^[rP~
* The everyPage to set. (GOrfr
*/ "?(Fb_}i
publicvoid setEveryPage(int everyPage){ \kGtYkctZ
this.everyPage = everyPage; 7tO$'q*h
} nVA'O
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/** dX}dO)%m{
* @return YhK/pt43C
* Returns the hasNextPage. ){|Lh(
*/ UNLNY,P/!)
publicboolean getHasNextPage(){ GYmB xX87
return hasNextPage; }uj'BO2?
} d3J_IW+8R$
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/** V~"d`j
* @param hasNextPage Z8n%=(He
* The hasNextPage to set. W$&Ets8zo
*/ 4zDAfi#0
publicvoid setHasNextPage(boolean hasNextPage){ mqc Z3lsv
this.hasNextPage = hasNextPage; 3Ty{8oUs^
} -#M~NbI,
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/** =QO[zke:
* @return fv'P!+)t
* Returns the hasPrePage. b'"%
*/ ;pK"N:|
publicboolean getHasPrePage(){ $5(%M8qmQ
return hasPrePage; }ucg!i3C
} 5!{g6=(
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t
/** *K)53QKlE
* @param hasPrePage 6]49kHgMhe
* The hasPrePage to set. eL4@%
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*/ PBnn,#
publicvoid setHasPrePage(boolean hasPrePage){ b<cM[GaV~
this.hasPrePage = hasPrePage; n.>'&<H>9
} \-id[zKb
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/** ?
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* @return Returns the totalPage. /s_$CSiB
* Ybg`Z
*/ =+\oL!^
publicint getTotalPage(){ 6_><W"r:]
return totalPage; Q*{
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} ,IB)Kk2
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/** 2~'quA
* @param totalPage %K,,Sl_
* The totalPage to set. n=MYv(Pp}
*/ Zul32]1r
publicvoid setTotalPage(int totalPage){ l@jJJ)Qyk
this.totalPage = totalPage; .HJHJ.Js8X
} B\w`)c
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} IKpx~
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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 v> PHn69PU
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个PageUtil,负责对Page对象进行构造:
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java代码: d7gSkna`5c
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/*Created on 2005-4-14*/ _/\H3
package org.flyware.util.page; Y>~zt -
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import org.apache.commons.logging.Log; 7!)%%K.z6
import org.apache.commons.logging.LogFactory; :M`BVZ1t
"VCr^'
/** Ry~LhU:
* @author Joa 0~+k
* ((q(Q9(F
*/ je%12DM
publicclass PageUtil { =?aB@&
,' B=eY,
privatestaticfinal Log logger = LogFactory.getLog gC 4#!P
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(PageUtil.class); -6>rR{z
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/** .[A S
* Use the origin page to create a new page =0Sa
* @param page ~`.%n7
* @param totalRecords |XZf:}q5:
* @return [%Xfl7;Wh
*/ 9$i`B>C~
publicstatic Page createPage(Page page, int ;& +75n
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totalRecords){ Dh<e9s:
return createPage(page.getEveryPage(), T]`"
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page.getCurrentPage(), totalRecords); 1)ne-e
} (
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/** fOAb?:D
* the basic page utils not including exception v2R:=d
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handler PN=yf@<V3F
* @param everyPage :f:C*mYvu
* @param currentPage HS9U.G>
* @param totalRecords 1uMdgrJRR
* @return page #u^d3
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*/ 39#>C~BOl
publicstatic Page createPage(int everyPage, int _L>n!"E/
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currentPage, int totalRecords){ p10->BBg
everyPage = getEveryPage(everyPage); WkE;tC*
currentPage = getCurrentPage(currentPage); pDQ,v"
int beginIndex = getBeginIndex(everyPage, ^<-SW]x
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currentPage); xH uyfQLk
int totalPage = getTotalPage(everyPage, ipG+qj/=
ww,'n{_
totalRecords); Ns(F%zkm
boolean hasNextPage = hasNextPage(currentPage, @}:(t{>;e7
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totalPage); zT"#9"["
boolean hasPrePage = hasPrePage(currentPage); 9"TPDU7"
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returnnew Page(hasPrePage, hasNextPage, W#7c`nm
everyPage, totalPage, ,@xZuq+K<
currentPage, ;C'*Ui
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beginIndex); bql6Z1l
} {;r5]wimb
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privatestaticint getEveryPage(int everyPage){ =9-c*bL
return everyPage == 0 ? 10 : everyPage; vr$[
} '"Gi&:*nQ<
ko$R%W&T
privatestaticint getCurrentPage(int currentPage){ =8-e1R/
return currentPage == 0 ? 1 : currentPage; -L@=j
} zuw6YY8kQ
N{0 D <"
privatestaticint getBeginIndex(int everyPage, int rcCMx"L=
:M16ijkx
currentPage){ "-
AiC6u
return(currentPage - 1) * everyPage; ?FyA2q!
} dL>ZL1.$
nm..$QL
privatestaticint getTotalPage(int everyPage, int Yhfk{ CI
t"Rn#V\c."
totalRecords){ (#~063N,#
int totalPage = 0; K9c:K/H
I5{SC-7
if(totalRecords % everyPage == 0) L-yC 'C
totalPage = totalRecords / everyPage; E@p9vf->
else y$rp1||lH
totalPage = totalRecords / everyPage + 1 ; &LE/hA
wbTw\b=
return totalPage; <#sK~G
} x\WKsc
?]S*=6
privatestaticboolean hasPrePage(int currentPage){ 'tekne
return currentPage == 1 ? false : true; 8I%1
`V
} ynhH5P|6,
5n<Efi]j
privatestaticboolean hasNextPage(int currentPage, t+t&eg
[||$1u\%
int totalPage){ raCxHY
return currentPage == totalPage || totalPage == gU:jx
-4.+&'
0 ? false : true; _
._'\
} U:H*b{`TU
1jR<H$aS
6v-h!1p{u
} YvonZ
YC{od5a
] '..G-
umY4tNe]$
sNWj+T
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。 /}Max@.`
k#
/_Zd
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 kjH0u$n
z?7pn}-
做法如下: Lq:Z='Kc
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]`%cTdpLj
C
7v
8
的信息,和一个结果集List: :7'anj
java代码: \O[Cae:^?
!^w+<p
`3~w#?+=*
/*Created on 2005-6-13*/ |2Q;SaI^\
package com.adt.bo; uTQ/_$
O:4.xe
import java.util.List; -g~$HTsGm
@AJt/wPk
import org.flyware.util.page.Page; {B34^H:
dbw`E"g
/** Y%2<}3P
* @author Joa J}BS/Tr}=
*/ 9i n& \
publicclass Result { b1-JnEc
l&zd7BM9(
private Page page; a4?:suX$
P:=3;d{v
private List content; ,{$:Q}`
*g7dB2{
/** >>p3#~/
* The default constructor tcfUhSz,I
*/ Y>r9"X|&H
public Result(){ IYd)Vv3'j
super(); R ~#\gMs
} f5AK@]4G
AkGCIn3
/** 5E$)Ip
* The constructor using fields L0}"H
.
* #,Rmu
* @param page w _n)*he)z
* @param content ip~PF5
*/ ^b'[81%
public Result(Page page, List content){ A >Js`s
this.page = page; C]82Mt
this.content = content; Jjv,
)@yo
} uGOvZO^v
]w({5i
/** c8A
//
* @return Returns the content. !$P&`n]@
*/ Ie4}F|#=
publicList getContent(){ G0^NkH,k
return content; 0GEK xV\F
} jvA]EN6$;~
HKV]Rn
/** lCDXFy(E
* @return Returns the page. u9 J;OsnHK
*/ T0i_X(_
public Page getPage(){ ]oj
2
return page; :Fm)<VN"
} L9(fa+$+#
Ga"t4[=I
/** p3&w/K{L6w
* @param content \)pk/
* The content to set. 1s .Ose
*/ npZ=x-ce
public void setContent(List content){ ~]3y667
this.content = content; zGF_ c9X
} iXeywO2nP
zmF_-Q`c
/** F|9
W7
* @param page Qn_*(CSp
* The page to set. h5>JBLawQP
*/ 7YrX3Hx8
publicvoid setPage(Page page){ 46Vx)xX
this.page = page; YQLp#
} (=,p"3^
} l-g+E{ZM
I8rtta
"aHA6zTB
4fgA3%
'7 SFa]tH
2. 编写业务逻辑接口,并实现它(UserManager, a~jM^b;VN
G<U MZg
UserManagerImpl) lOYzo
java代码: 1*, f
'(4$h3-gv7
jNBvy1
/*Created on 2005-7-15*/ EA8K*>'pv
package com.adt.service; ;b-Y$<
^^1rjh1I
import net.sf.hibernate.HibernateException; QE1DTU
#**vIwX-Q
import org.flyware.util.page.Page; 2Ck'A0d
bd_&=VLTC
import com.adt.bo.Result; gq\ulLyOeZ
$n.oY5=\
/** XDRw![H,~
* @author Joa M:YtW5{
*/ Z(k7&^d
publicinterface UserManager { )OpB\k
d ]R&mp|'
public Result listUser(Page page)throws wGr5V!
!*5vXN
HibernateException; 3=SIIMp7=
)*Xd
} *z&m=G\
/{QR:8}-Q
Y%m^V?k
KF(N=?KO
FwKT_XkY
java代码: {N!Xp:(<7_
e:#c\Ay+
D',[M)
/*Created on 2005-7-15*/ K=nW|^
package com.adt.service.impl; mWN9/+!
4EQ-48h17
import java.util.List; .s Ci9d
WR
V/"P};n
import net.sf.hibernate.HibernateException; ancs
]n _OQ)VO
import org.flyware.util.page.Page; OFH!z{*
import org.flyware.util.page.PageUtil; ?Zu2=<DU
9O1#%
import com.adt.bo.Result; C{^U^>bU
import com.adt.dao.UserDAO; HuzHXn)
import com.adt.exception.ObjectNotFoundException; `tZ m
import com.adt.service.UserManager; csABfxib
\qk+cK;+
/** apFY//(yu
* @author Joa Uskz~~}G
*/ F6,[!.wl
publicclass UserManagerImpl implements UserManager { ) bRj'*
)4u6{-|A
private UserDAO userDAO; G>Uam TM
pH!e<m
/** MOp06
* @param userDAO The userDAO to set. walQo^<
*/ ]N<:6+
publicvoid setUserDAO(UserDAO userDAO){ BUhLAO
this.userDAO = userDAO; Y;n;7M<F
} P4H%pm{-
/1OzX'5f
/* (non-Javadoc) JzI/kH~
* @see com.adt.service.UserManager#listUser l.gt+e
c0}* $e
(org.flyware.util.page.Page) q3Tp/M.
*/ I#?NxP\S
public Result listUser(Page page)throws &"G4yM
|1M+FBT$w
HibernateException, ObjectNotFoundException { vMT:j
int totalRecords = userDAO.getUserCount(); H! IL5@@K
if(totalRecords == 0) (4ueO~jb$
throw new ObjectNotFoundException {[Sd[P
x.J%
c[Q8
("userNotExist"); k(As^'>
page = PageUtil.createPage(page, totalRecords); VkKq<`t<
List users = userDAO.getUserByPage(page); e&*< "WN
returnnew Result(page, users); U TT 7a"
} q4Z9;^S
e;_ cC7
} wlvh DJ
e[`u:
Qqju6} +
E}&Z=+v}
F^knlv'
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 b d!|/Lk
0qND 2_
询,接下来编写UserDAO的代码: k#*tf:R
3. UserDAO 和 UserDAOImpl: q].n1w[
java代码: 4^|;a0Qy]
~D[5AXV`^
@t W;(8-
/*Created on 2005-7-15*/ UM?{ba9
package com.adt.dao; CY{`IZ
4&TTPcSt;
import java.util.List; !4gyrNS
UBN^dbP*
import org.flyware.util.page.Page; /<J&ZoeJB
qhNY<
import net.sf.hibernate.HibernateException; S4qj}`$
Yv
DH@})TN*O
/** RfM
uWo:
* @author Joa #:C?:RMS
*/ {OK+d#=
publicinterface UserDAO extends BaseDAO { ^&nC)T<w
5|I2
publicList getUserByName(String name)throws e7fA-,DV
S w<V/t
HibernateException; $8kQM
Mwm=r//
publicint getUserCount()throws HibernateException; _9@D o6
?hW?w$C
publicList getUserByPage(Page page)throws 7hQf
T76h
f(Hh(
HibernateException; >%v w(pt
Woo2hg-ti
} Z33&FUU
7.G1Q]6/
5)%bnLxn
GoVB1)
G'*_7HD
java代码: WGxe3(d
[8T
Ib$*w)4:
/*Created on 2005-7-15*/ 3M/iuu
package com.adt.dao.impl; }YPW@g
1Tn0$+$.4
import java.util.List; S}0W<H P
+Xa^3 =B
import org.flyware.util.page.Page; y-Xd~<*Ia
IB!^dhD!Q
import net.sf.hibernate.HibernateException; K]0Q=HY{.
import net.sf.hibernate.Query; hJ)>BeH0
HLjXH#ry
import com.adt.dao.UserDAO; W6kDQ&q
) ?AlQA
/** ppwjr
+
* @author Joa Y6_%HYI$
*/ u9d4zR
public class UserDAOImpl extends BaseDAOHibernateImpl bo;;\>k
IV"OzQONx
implements UserDAO { ^>?E1J3u
s|/m}n
/* (non-Javadoc) /U|>
* @see com.adt.dao.UserDAO#getUserByName a{?`yO/ 2
mY}_9rTn|
(java.lang.String) =U:9A=uEvS
*/ vrS)VJg`
publicList getUserByName(String name)throws lu]Z2xSv
,34|_
HibernateException { iG:9uDY
String querySentence = "FROM user in class 6CK WKc
H|E{n/g
com.adt.po.User WHERE user.name=:name"; |2!!>1k
Query query = getSession().createQuery t#kPEiD
pHW
Qk z(
(querySentence); 5IK -V)
query.setParameter("name", name); uVO*@Kj+
return query.list(); 3$]SP1Mc(
} 1x\Vz\
M5mCG
/* (non-Javadoc) .GJl@==~1
* @see com.adt.dao.UserDAO#getUserCount() R"j6 w[tn
*/ mp^;8??;
publicint getUserCount()throws HibernateException { 6usy0g
D
int count = 0; 1l@gZI12#/
String querySentence = "SELECT count(*) FROM U#o5(mK
?dWfupO{
user in class com.adt.po.User"; $On
Query query = getSession().createQuery /}_OCuJJ,
%?o@YwBo^E
(querySentence); fS( )F*J
count = ((Integer)query.iterate().next ?,dbrQ
@;T>*_Yhn
()).intValue(); RVlAWw(
return count; |FF"vRi8a7
} l7rGz2:?
&VY(W{\eY
/* (non-Javadoc) (-V=&F_
* @see com.adt.dao.UserDAO#getUserByPage oiG@_YtR
D.e4S6\&
(org.flyware.util.page.Page) UV ?.KVD~
*/ x#mZSSd
publicList getUserByPage(Page page)throws w(lxq:>"
/0w?"2-
HibernateException { Yl65|=ne
String querySentence = "FROM user in class ?*I
_'2
R~z@voM*<
com.adt.po.User"; m,zZe}oJ
Query query = getSession().createQuery o_2mSD!
}]-SAM
(querySentence); c$<7&{Pb
query.setFirstResult(page.getBeginIndex()) =r<0l=
.setMaxResults(page.getEveryPage()); \\j98(i
return query.list(); 8QFn/&Ql$B
} i.4L;(cg
v>vU]6l
} Rp#9T?i``[
Ivw+U-Mz
$gYy3y
mY+.(N7m
'O#,;n
至此,一个完整的分页程序完成。前台的只需要调用 eRlJ
n&?]GyQ
userManager.listUser(page)即可得到一个Page对象和结果集对象 Z19d Ted33
UOWOOdWSB
的综合体,而传入的参数page对象则可以由前台传入,如果用 *{5L*\AZ
X%+FM]
webwork,甚至可以直接在配置文件中指定。 $,vZX u|Qw
-0KQR{LI
下面给出一个webwork调用示例: $Cr? }'a
java代码: )~hsd+ 0t
!Ua74C
R~-r8dWcw
/*Created on 2005-6-17*/ "HWl7c3q
package com.adt.action.user; \wmNeGC2
Ga4Ru
import java.util.List; X@,xwsM%tb
SE0"25\_G
import org.apache.commons.logging.Log; '/gw`MJ
import org.apache.commons.logging.LogFactory; #y~`nyg%|
import org.flyware.util.page.Page; jni }o m
:!vDX2o)\
import com.adt.bo.Result; X
X>Y]P
a
import com.adt.service.UserService; E6);\SJG}
import com.opensymphony.xwork.Action; >$gWeFu
x\ :x`k@
/** i8$tId
* @author Joa w!NtN4>
*/ ~jd:3ip+!
publicclass ListUser implementsAction{ Qp{rAAC:
O,Xf.O1c
privatestaticfinal Log logger = LogFactory.getLog t I9$m[
AT^?PD_
(ListUser.class); &i`\`6 q
e+"rL]
private UserService userService; opz.kP[e,
H6<\7W89y
private Page page; uJ S+;H
jW6~^>S
privateList users; q#v&&]N=
~o:lh],~
/* ojO<sT:by
* (non-Javadoc) P |c6V
* A[lkGQtS4
* @see com.opensymphony.xwork.Action#execute() .tB[8Y =J
*/
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publicString execute()throwsException{ S3-3pJ]~Zk
Result result = userService.listUser(page); [YT"UVI
page = result.getPage(); C7%+1w'D8
users = result.getContent(); +p =n-
return SUCCESS; w'q}aQS
} @DT${,.49
I71kFtvcy*
/** ]A;zY%>
* @return Returns the page. 4ze-N8<[
*/ =K#D^c~
public Page getPage(){ d+KLtvB%M
return page; 9C5w!_b@
} v&}mbt-
V0mWY!i
/** sL;qC\S
* @return Returns the users. zBWn*A[4
*/ brN:Ypf-e
publicList getUsers(){
4LYeacL B
return users; wU_e/+0h
} Q7`}4c)
qw[)$icP
/** [Q,E(
s
* @param page uX@RdkC
* The page to set. h?2qX
*/ 4oLrCQZ\
publicvoid setPage(Page page){ ![os5H.b#q
this.page = page; R9gK> }>Y
} e7/ b@
X:\ r )
/** fZ6lnZ
* @param users tk4~ 8
* The users to set. yG?,8!/]
*/ bit&H
publicvoid setUsers(List users){ //VgPl
this.users = users; +*[lp@zU{
} ;4of7d
kS[xwbE
/** .63:G<
* @param userService 5haJPWG|'
* The userService to set. xMDx<sk
*/ 8$<jd^w
publicvoid setUserService(UserService userService){ 0|8c2{9X,
this.userService = userService; [QA@XBy6
} ~;W]0d4,\
} AE1!u{
y5>859"h
U3MfEM!x
^G{3x
gq`gitu0
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, $Jo[&,
q#Az\B:
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 KumbG>O
F+R4nFA
么只需要: Oqeoh<y!\
java代码: g$eb@0$
ZRO
7Zp'}Om<I
<?xml version="1.0"?> \I; lgz2
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _*B]yz6z
17[7)M88
1.0//EN" "http://www.opensymphony.com/xwork/xwork- )BudV zg
7{j9vl6
1.0.dtd"> +`l>_u'
)r-t$ L
<xwork> uiDK&@RS
9vT@ mqKu
<package name="user" extends="webwork- ^2OBc
U/&!F
interceptors"> |xyN#wi
&AH@|$!E
<!-- The default interceptor stack name 1Qui.],c
PiXegh WH
--> kL,bM.;
<default-interceptor-ref |XOD~Plo^
cP63q|[[
name="myDefaultWebStack"/> j?4k{?x
aH'Sz'|E
<action name="listUser" E[HXbj"
TTpK8cC
class="com.adt.action.user.ListUser"> !'(bwbd
<param a5C% OI<
J3cbDE%^m
name="page.everyPage">10</param> P4"_qxAW
<result to9
u%d 8
k$?zh$
name="success">/user/user_list.jsp</result> 8r(S=dA
</action> c?5e| dZz
xJrRJwL
</package> #+V-65v
<SmXMruU
</xwork> mR:G,XytxM
ECqcK~h#E
Y!* \=h6h
B!H46w~
54s+4R FL
+{N LziO
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 =xScHy{$
B ?96d'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。 Alaq![7MDP
(D F{l?4x-
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Fp..Sjh
6
q:@$$}FjL
%k
@ "*
j@$p(P$
cx M=#Go
我写的一个用于分页的类,用了泛型了,hoho dQLR%i#P8
XzGPBi
java代码: 2V7x
`=^;q6f
wND0KiwH
package com.intokr.util; T:IKyb
`!Ei
H<H}
import java.util.List; <&E3QeK
TcA+ov>TD
/** 0G?0 Bo
* 用于分页的类<br> )MqF~[k<-
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?3jOE4~aHr
* V~M>K-AL
* @version 0.01 {^ 1s
* @author cheng JnE\E(ez
*/ .q#2 op
public class Paginator<E> { hGyi@0
privateint count = 0; // 总记录数 c<)C3v
privateint p = 1; // 页编号 :J` *@cDn
privateint num = 20; // 每页的记录数 |uVhfD=NG
privateList<E> results = null; // 结果 ! 4 `any
nf?;h!_7
/** Cp(,+dD
* 结果总数 =o]V!MW
*/ Wo&10S w
publicint getCount(){ f@&C
\
return count; '^"6EF.R
} 3D70`u
afOb-G$d=
publicvoid setCount(int count){ v+ dt1;
this.count = count; (%]&Pe]
} QWG?^T
fi
i~:FlW]
/** .n1]Yk;,1
* 本结果所在的页码,从1开始 !~PLW] Z4
* 1^rODfY 0
* @return Returns the pageNo. .PBma/w
W
*/ pv1J6
publicint getP(){ f@lRa>Z(Fm
return p; u! `oKe;
} %cJ]Ds%V
@q2If{Tk
/** ] >-#T
* if(p<=0) p=1 %tiFx:F+
* zS*GYE(l^
* @param p (wLzkV/6
*/ Q| >
\{M
publicvoid setP(int p){ Wo=Q7~
if(p <= 0) Rr+Y::E
p = 1; KY$6=/?U_
this.p = p; mwLp~z%OX
} Kt3/C'zu
*L>gZ`Q
/** `~Nd4EA)2
* 每页记录数量 =;Gy"F1 dp
*/ "pTyQT9P
publicint getNum(){ "Wd?U[[
return num; 9NvV{WI-1
} 4jEPh{q
j&) "a,f
/** 6KP"F[8I
* if(num<1) num=1 6-C9[[g<
*/ ]p>6r*/nw
publicvoid setNum(int num){ 6'd=% V
if(num < 1) R4=n">>Q
num = 1; i_T8Bfd:
this.num = num; "2:]9j
} VKRj
1LXz
kK+<n8R2
/** /]4[b!OTJ
* 获得总页数 aW$(lf2;
*/ $FUWB6M
publicint getPageNum(){ }.w@.
S"
return(count - 1) / num + 1; Q-78B'!=
} 7KU/ 1l9$9
b489sa
/** QZ(se
* 获得本页的开始编号,为 (p-1)*num+1 (5S(CYls
*/ p\5DW'
publicint getStart(){ gf2<dEff
return(p - 1) * num + 1; ZVu&q{s,
} .nX+!EXeS
aLapb5VV
/** l%]S7|PKx
* @return Returns the results. ;7CE{/Bq.p
*/ D/C,Q|Ya6
publicList<E> getResults(){ y1P KoN|K
return results; `iuo([E d
} }I_/>58
`ZL~k
public void setResults(List<E> results){ m'H%O-h\
this.results = results; v7"' ^sZ?
} Wi ]Mp7b
]0<T,m Z
public String toString(){ sLh9=Kh`
StringBuilder buff = new StringBuilder BhC.#u/
gd3~R+Kd
(); `ro~l_U;A
buff.append("{"); ~ldqg2c
buff.append("count:").append(count); xv;'27mUt
buff.append(",p:").append(p); +BcJHNIB
buff.append(",nump:").append(num); v#i,pBj
buff.append(",results:").append 2OFrv=F
3]Rb2$p[=
(results); J{c-'Of2yi
buff.append("}"); boAu
return buff.toString(); NFpR jC?
} ~*R"WiDtI
iW\cLp "
} <}x_F)E[t
eglcf z%
A+i|zo5p=k