Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 \ZU1Jb1c
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 h vka{LD
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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 ',^+bgs5
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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 ~@.%m"<.
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分页支持类: 0&_UH}10
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java代码: ?L&|Uw+
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package com.javaeye.common.util; \;u@ "
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import java.util.List; b` Hz$8
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publicclass PaginationSupport { 1K,1X(0rL8
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publicfinalstaticint PAGESIZE = 30; U-/{0zB
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privateint pageSize = PAGESIZE; VA*y|Q6
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privateList items; OCZaQ33
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privateint totalCount; Sf5X3,Uw
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privateint[] indexes = newint[0]; ;2'q_Btk4
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privateint startIndex = 0; 4SPy28<f
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public PaginationSupport(List items, int =0uAE7q(9
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totalCount){ EnOU?D
setPageSize(PAGESIZE);
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setTotalCount(totalCount); AL#4_]m'
setItems(items); bwiPS1+);
setStartIndex(0); l2N]a9bq@
} iY"l}.7)
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public PaginationSupport(List items, int !*6CWV0
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totalCount, int startIndex){ sVG(N.y
setPageSize(PAGESIZE); =] *.ZH#h
setTotalCount(totalCount); mU}F!J#6
setItems(items); pvmC$n^zc
setStartIndex(startIndex); F1L:,.e`
} a:QDBS2Llv
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public PaginationSupport(List items, int M%jPH
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totalCount, int pageSize, int startIndex){ UfS%71l.$
setPageSize(pageSize); y ]?V~%
setTotalCount(totalCount); ME'|saP
setItems(items); 3Zi@A4Wu
setStartIndex(startIndex); k'0Pi6
} 6 G=j6gK%P
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publicList getItems(){ xhcK~5C
return items; ZXm/A0)S
} 4:g R r
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publicvoid setItems(List items){ giz7{Ai
this.items = items; gz3pX#S
} {nLjY|*
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publicint getPageSize(){ ,}K<*t[I
return pageSize; [jmd
} bw\@W{a%q
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publicvoid setPageSize(int pageSize){ b0oMs=uBn
this.pageSize = pageSize; C*P7-oE2rh
} B(M6@1m_
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publicint getTotalCount(){ 0jEL<TgC
return totalCount; n=[/Z!
} Yk=PS[f
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publicvoid setTotalCount(int totalCount){ i':C)7
if(totalCount > 0){ _4g.j
this.totalCount = totalCount; eUg~)m5G
int count = totalCount / e=.]F*:J
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pageSize;
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if(totalCount % pageSize > 0) <>Hj
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count++; (DI>5.x"
indexes = newint[count]; 6'Fd GS
for(int i = 0; i < count; i++){ Cg(Y&Gxf.
indexes = pageSize * X7rMeu
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i; SJHr_bawd
} -,U3fts
}else{ aTt12Sc
this.totalCount = 0; '*3h!lW1.
} kBffF@{
} ?nL.w
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publicint[] getIndexes(){ UeRj< \"Q
return indexes; ;n
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} w4gJoxY-`
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publicvoid setIndexes(int[] indexes){ 9E6_]8rl
this.indexes = indexes; `E>1>'
} Ig
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publicint getStartIndex(){ P}4QQw
return startIndex; .4E&/w+
} .nVa[B|.
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publicvoid setStartIndex(int startIndex){ -X"p:=;j
if(totalCount <= 0) }R{ts
this.startIndex = 0; -[wGX}}
elseif(startIndex >= totalCount) aJ>65RJ^=
this.startIndex = indexes lz?$f4TzA
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[indexes.length - 1]; |AozR ~
elseif(startIndex < 0) N(Tz%o4
this.startIndex = 0; @"^0%/2-
else{ WHj'dodS
this.startIndex = indexes tIuCct-
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[startIndex / pageSize]; W>j !Q^?
} M
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} c_4[e5z
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publicint getNextIndex(){ TIQkW,
int nextIndex = getStartIndex() + N$U$5;r~`
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pageSize; lIW
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if(nextIndex >= totalCount) bAx-"Lu
return getStartIndex(); q!|*oUW
else $}!p+$
return nextIndex; ?B2] -+Y
} Gz,i~XX
!1$])VQWI
publicint getPreviousIndex(){ 4b98KsYg
int previousIndex = getStartIndex() - )p<ExMIxd
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pageSize; 0.8 2kl
if(previousIndex < 0) }&wUr>=
return0; ^c9t'V`IWQ
else CEX"D`
return previousIndex; +JjW_Rl?=V
} n[lJLm^(_C
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} z=q3Zo
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抽象业务类 CxwoBuG=?
java代码: LG9+y
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/** =THpdtL
* Created on 2005-7-12 fSK]|"c
*/ JB<Sl4
package com.javaeye.common.business; um!J]N^
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import java.io.Serializable; O$_)G\\\m
import java.util.List; |)(VsVG&
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import org.hibernate.Criteria; S4Y&
import org.hibernate.HibernateException; u)}$~E>
import org.hibernate.Session; UC]\yUK1J
import org.hibernate.criterion.DetachedCriteria; =8AO:
import org.hibernate.criterion.Projections; oX30VfT
import 5z7U1:
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org.springframework.orm.hibernate3.HibernateCallback; &"&Z
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import QdF5Cwf4
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org.springframework.orm.hibernate3.support.HibernateDaoS ILEz;D{]
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upport; WW4vn|0v
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import com.javaeye.common.util.PaginationSupport; Br1&8L-|%
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public abstract class AbstractManager extends zzTfYf)
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HibernateDaoSupport { u0|8Tgf
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privateboolean cacheQueries = false; X' H[7 ^W
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privateString queryCacheRegion; gQWa24
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publicvoid setCacheQueries(boolean I*{4rDt
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cacheQueries){
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this.cacheQueries = cacheQueries; Mo?~_|}
} 8m2Tk\;:
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publicvoid setQueryCacheRegion(String ZSjMH .Ij"
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queryCacheRegion){ b=yx7v"r
this.queryCacheRegion = A9I{2qW9+Z
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queryCacheRegion; +ga k#M"n\
} HHDl8lo
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publicvoid save(finalObject entity){ T!+5[
getHibernateTemplate().save(entity); QM5R`i{r
} ;RDh~EV
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publicvoid persist(finalObject entity){ n0r+A^]
getHibernateTemplate().save(entity); [Dk=? +
} q)X$^oE!6
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publicvoid update(finalObject entity){ ^t` k0<
getHibernateTemplate().update(entity); rI= v
} be]bZ
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publicvoid delete(finalObject entity){ s.bc>E0
getHibernateTemplate().delete(entity); 27
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} TSTl+W
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publicObject load(finalClass entity, nKPYOY8^
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finalSerializable id){ K&vF0*gN3
return getHibernateTemplate().load R<\F:9
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(entity, id); /1"(cQ%?
} x'+T/zw
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publicObject get(finalClass entity, 3LAIl913
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finalSerializable id){ 5's87Z;6
return getHibernateTemplate().get XC4X-j3
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(entity, id); Ov5"
} w`4=_J=GO
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publicList findAll(finalClass entity){ ^8 z R
return getHibernateTemplate().find("from rf
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" + entity.getName()); $;1#To
} )m`<H>[Eb=
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publicList findByNamedQuery(finalString
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namedQuery){ 2/vMoVT,
return getHibernateTemplate PPb7%2r
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().findByNamedQuery(namedQuery); cJ{ Nh;"
} I;e=0!9U
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publicList findByNamedQuery(finalString query, W#^2#sjO
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finalObject parameter){ dCE0$3'5
return getHibernateTemplate < vL,*.zd
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().findByNamedQuery(query, parameter); 1,6}_MA
} @Ws*Q TlV
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publicList findByNamedQuery(finalString query, hlV=qfc
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finalObject[] parameters){ Wi*.TWz3
return getHibernateTemplate s%qF/70'
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().findByNamedQuery(query, parameters); g
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} cv?06x{
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publicList find(finalString query){ w$+&3t
return getHibernateTemplate().find a6D &/8
q;R],7Re
(query); ;|pBFKx
} J#w
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publicList find(finalString query, finalObject Tu$f?
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parameter){ zDw5]*R
return getHibernateTemplate().find GC?ON0g5s
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(query, parameter); ~ DBcIy?
} ",^Mxm{
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public PaginationSupport findPageByCriteria ]^Qn
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(final DetachedCriteria detachedCriteria){ >[9J?H
return findPageByCriteria ukIQr/k
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 9f2UgNqe9
} G~Hzec{#tg
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public PaginationSupport findPageByCriteria SO IHePmwK
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(final DetachedCriteria detachedCriteria, finalint tasIDoo+!J
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startIndex){ IEXt:
return findPageByCriteria }@;ep&b*
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(detachedCriteria, PaginationSupport.PAGESIZE, q#T/
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startIndex); Q~OxH'>>(
} H| 8Qp*
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public PaginationSupport findPageByCriteria v16JgycM
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(final DetachedCriteria detachedCriteria, finalint 3
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pageSize, b:Wm8pp?
finalint startIndex){ xCg52zkH#
return(PaginationSupport) ox(j^x]NC
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getHibernateTemplate().execute(new HibernateCallback(){ pnjXf.g"O
publicObject doInHibernate C1jHz
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(Session session)throws HibernateException { +?:7O=Y
Criteria criteria = z`!XhU
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detachedCriteria.getExecutableCriteria(session); }])oM|fgO
int totalCount = )\eI;8
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((Integer) criteria.setProjection(Projections.rowCount L W[9
m;'6MHx;
()).uniqueResult()).intValue(); PK{acen
criteria.setProjection jF0jkj1&/[
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(null); gu0j.XS^
List items = iH/6M
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criteria.setFirstResult(startIndex).setMaxResults Jth[DUH8H
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(pageSize).list(); *A"~m!=
PaginationSupport ps = {U1?Et#
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new PaginationSupport(items, totalCount, pageSize, M-1ngI0H;
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startIndex); l8I /0`_
return ps; swK-/$#
} +3BBQ+x!
}, true); E~]R2!9
} 9fhsIe
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public List findAllByCriteria(final
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DetachedCriteria detachedCriteria){ 7*
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return(List) getHibernateTemplate *~t6(v?
4)@mSSfn.
().execute(new HibernateCallback(){ WU
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publicObject doInHibernate X$ s:>[H
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(Session session)throws HibernateException { E%rk[wI
Criteria criteria = 'eLqlu|T
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detachedCriteria.getExecutableCriteria(session); q1QL@Ax
return criteria.list(); \P.I)n`8 y
} l038%U~U!
}, true); h| ,:e;>}
} 6LalW5I
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public int getCountByCriteria(final RloK,bg
n?- })
DetachedCriteria detachedCriteria){ \Ta"}TF8
Integer count = (Integer) &Xf^Iu
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getHibernateTemplate().execute(new HibernateCallback(){ )iYxt:(,
publicObject doInHibernate
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(Session session)throws HibernateException { ~:Ll&29i
Criteria criteria = SKkUU^\#R`
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detachedCriteria.getExecutableCriteria(session); kQEy#JQmB
return tasUZ#\6
B" !l2
criteria.setProjection(Projections.rowCount a-=8xs'
^; )8VP6
()).uniqueResult(); @\f^0^G
} S/9DtXQ
}, true); {]%0lf:
return count.intValue(); \l9qt5rS
} Dey<OE&
} czS+<
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用户在web层构造查询条件detachedCriteria,和可选的 J|~MC7#@q
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 umt.Um.m2
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PaginationSupport的实例ps。 FB{KH .
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ps.getItems()得到已分页好的结果集 yCVI\y\B
ps.getIndexes()得到分页索引的数组 @~YYD#'vNY
ps.getTotalCount()得到总结果数 ;\14b?TUH
ps.getStartIndex()当前分页索引 LUM@#3&
ps.getNextIndex()下一页索引 0{,Z{&E
ps.getPreviousIndex()上一页索引 dep=&
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 UA48Ug
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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 6L"%e!be6
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一下代码重构了。 |mGFts}0o'
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我把原本我的做法也提供出来供大家讨论吧: +@p%
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首先,为了实现分页查询,我封装了一个Page类: y5*Z3"<
java代码: =a@j=
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/*Created on 2005-4-14*/ pe] A5\4c
package org.flyware.util.page; 60J;sGW
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/** nxWY7hU
* @author Joa ]:Nsf|C0
* >z%&xgOa
*/ ]n_
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publicclass Page { GO`Ru 8
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/** imply if the page has previous page */ El.hu%#n*G
privateboolean hasPrePage; C8Qa$._
i rU 6D
/** imply if the page has next page */ e4H A7=z
privateboolean hasNextPage; ew#B[[
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/** the number of every page */ Y2n!>[[.
privateint everyPage; BK)$'AqO
g;qx">xJ`o
/** the total page number */ YQHw1
privateint totalPage; }<@b=_>S
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/** the number of current page */ iOU6V
privateint currentPage; mz,
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/** the begin index of the records by the current D~hg$XzK
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query */ E"qRw_
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privateint beginIndex; &cxRD
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/** The default constructor */ @k,z:~[C=
public Page(){ /Z~<CbKKl
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} 8$6Y{$&C
V@zg}C|e
/** construct the page by everyPage iBF|&h(\
* @param everyPage %?}33yV
* */ i~I%D%;
public Page(int everyPage){ }001K
this.everyPage = everyPage; sf)EMh3Z
} L ^q""[
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/** The whole constructor */ ,l!Ta"
public Page(boolean hasPrePage, boolean hasNextPage, _FH`pv
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int everyPage, int totalPage, oW ::hB
int currentPage, int beginIndex){ "P7nNa
this.hasPrePage = hasPrePage; ;<&*rnH
this.hasNextPage = hasNextPage; ar__ Pf6r
this.everyPage = everyPage; Jm xH"7hTE
this.totalPage = totalPage; JMrEFk
this.currentPage = currentPage; SxOC1+Oy
this.beginIndex = beginIndex; TW)c#P43K
} (s.0PO`
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/** QRHu3w
* @return {:6r;TB
* Returns the beginIndex. ,}3
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*/ w,#>G07D
publicint getBeginIndex(){ em,u(#)&
return beginIndex; "i y
} %zG;Q@
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/** K2TcOFQ
* @param beginIndex CyS$|E
* The beginIndex to set. &]`(v}`]
*/ ''yB5#^w(
publicvoid setBeginIndex(int beginIndex){ r_
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this.beginIndex = beginIndex; r[|Xy>Zj
} ',9V|jvK
't:;irLW.
/** OI|[roMK
* @return b$N2z
* Returns the currentPage. 9IjIIM2y
*/ yA)/Q
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publicint getCurrentPage(){ );#JL0I
return currentPage; EK{Eo9l
} ]{3)^axW;
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/** 8&GBV_`I
* @param currentPage 4{y)TZ
* The currentPage to set. zQcL|(N
*/ r)y=lAyF>
publicvoid setCurrentPage(int currentPage){ bo2H]PL*
this.currentPage = currentPage; = bfJ^]R
} 7%5z p|3
@$ne{2J3
/** $ `ov4W
* @return zd2)M@
* Returns the everyPage. kVkU)hqR
*/ xN5)
publicint getEveryPage(){ `, OG7hg
return everyPage; mWoAO@}Y
} o}
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s^Y"' ` +
/** $Q &lSVQ
* @param everyPage K'L^;z6
* The everyPage to set. vx>b^tJKC
*/ VEWi_;=J1
publicvoid setEveryPage(int everyPage){ -.1y(k^4E
this.everyPage = everyPage; Bal$+S
} GzhYY"iif#
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/** `` ,fodA8
* @return gZN8!#h}B
* Returns the hasNextPage. wo4;n9@I
*/ h{%nC>m;
publicboolean getHasNextPage(){ e^8 O_VB
return hasNextPage; c23oCfB>
} VLOO8N[o
zwhe
/** 2M.fLQ?
* @param hasNextPage qraSRK5
* The hasNextPage to set. gH$ Mr
*/ Y\D!/T
publicvoid setHasNextPage(boolean hasNextPage){ n`#tKwWHYx
this.hasNextPage = hasNextPage; H=<S 9M
} ND'E8Ke pq
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/** Z_$%.
* @return C^O
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* Returns the hasPrePage. =O&%c%~q
*/ $mu^G t
publicboolean getHasPrePage(){ APvDP?
return hasPrePage; W<bGDh
} @P#N2:jwj
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/** V[RF</2T
* @param hasPrePage {:Orn%Q
* The hasPrePage to set. ( Z619w
*/ !=pn77`g>
publicvoid setHasPrePage(boolean hasPrePage){ Q8T]\6)m
this.hasPrePage = hasPrePage; 1#C4;3i,
} b,5~b&<h
.8@$\ZRP
/** (jnQ
-
* @return Returns the totalPage. D[4u+g?[}>
* r)lEofX,g+
*/ 8NxM4$nQX
publicint getTotalPage(){ B}n,b#,*
return totalPage; L9r8BK;
} J*r*X.
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/** w{Ivmdto
* @param totalPage ^hG-~z<
* The totalPage to set. UvJ}b
*/ @'w"R/,n-@
publicvoid setTotalPage(int totalPage){ :G [|CPm-
this.totalPage = totalPage; c?tBi9'Y]
} q_Q/3rh
y0Fb_"}
} &:;:"{t}Do
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U\ ig:
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ?ME6+Z\
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个PageUtil,负责对Page对象进行构造: 35A|BD)q
java代码: ?8I?'\F;
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<->{
/*Created on 2005-4-14*/ o15-ZzE-
package org.flyware.util.page; KxI&G%z
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import org.apache.commons.logging.Log; mi=Q{>rb
import org.apache.commons.logging.LogFactory; iNWw;_|1
:yL] ;J
/** ed]=\Key
* @author Joa viW!,QQ(S
* .!Qki@
*/ %<)2/|lCd
publicclass PageUtil { <C_jF
w;;BSJ]+[
privatestaticfinal Log logger = LogFactory.getLog c>,'Y)8
@GPCwE1
(PageUtil.class); ~,d,#)VE2q
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/** s28`OKC}
* Use the origin page to create a new page XR8,Vt)=
* @param page g$":D
* @param totalRecords #9B)Xx!g
* @return J; 3{3
*/ O%Scjm-^X
publicstatic Page createPage(Page page, int Rvkedb
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totalRecords){ )s)I2Z+
return createPage(page.getEveryPage(), 4qphA9i1
h(<,fg1
page.getCurrentPage(), totalRecords); /vY(o1o
x
} _- [''(E
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/** qPWP&k
* the basic page utils not including exception }HL]yDO
q
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handler e2L0VXbb
* @param everyPage 6}Vf\j~
* @param currentPage 9
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* @param totalRecords nxY\|@
* @return page u9:`4b
*/ Yw22z #K
publicstatic Page createPage(int everyPage, int sW Qfr$^A
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currentPage, int totalRecords){ A;G;^s
everyPage = getEveryPage(everyPage); @d^Grm8E
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, Ot$-!Y;<
>L|;|X!m9\
currentPage); @+;$jRwq
int totalPage = getTotalPage(everyPage, @v$Y7mw3D
;5wn67'
totalRecords); `Y+J-EQ
boolean hasNextPage = hasNextPage(currentPage, o=u3&liBi
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totalPage); WKQ^NEqr3
boolean hasPrePage = hasPrePage(currentPage); =Ee&da^MB
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returnnew Page(hasPrePage, hasNextPage, /Y*WBTV'
everyPage, totalPage, 7@#>bE6
currentPage, 4]rnY~
pny11C
beginIndex); ylUrLQ\
} .v]IJfRH*
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privatestaticint getEveryPage(int everyPage){ F@^~7ZmP`
return everyPage == 0 ? 10 : everyPage; kHkpx52
} ^le<}
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privatestaticint getCurrentPage(int currentPage){ Q0$8j-1I
return currentPage == 0 ? 1 : currentPage; T`/AY?#
} >@BnV{ d
,V'o4]H
privatestaticint getBeginIndex(int everyPage, int ,4hJT
he#J|p
currentPage){ H12Fw'2
return(currentPage - 1) * everyPage; iy6On,UL
} 2^XGGB0
7;u
e
privatestaticint getTotalPage(int everyPage, int 4)E_0.C
#w;v0&p
totalRecords){ rI{=WPI&WU
int totalPage = 0; "B8Q:
Tb A}BFT`
if(totalRecords % everyPage == 0) D,m]CK'
totalPage = totalRecords / everyPage; ;1#H62Z*
else Gk967pC
totalPage = totalRecords / everyPage + 1 ; 5Y?L>QU"
*v?`<)P#
return totalPage; du+y5dw
} k2E0/ @f{k
zFfoqb#*g
privatestaticboolean hasPrePage(int currentPage){ R= a|Blp
return currentPage == 1 ? false : true; liEPCWl&
} O[# 27_dH
d[r#-h>dS
privatestaticboolean hasNextPage(int currentPage, kTKq/G,Ft
01[NX? qEa
int totalPage){ :Y-{Kn6`_
return currentPage == totalPage || totalPage == }p=Jm)y
,?PTcQF
0 ? false : true; Wi>!{.}%A
} M]<?k]_p
U2$d%8G
|\w=u6jX
} ^*S ,xP
wU8Mt#D!
QpZ:gM_
:d3bt~b'
~7Y+2FZ
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。 V=)_yIS
Gb"r|(!
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 l|xZk4@_uE
_a_7,bk5
做法如下: 0WT{,/>
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 hhb?6]Z/
n-5W*zk1
的信息,和一个结果集List: b6W2^tr-
java代码: |lXc0"H[o
h"`ucC8X
r/& sub"X
/*Created on 2005-6-13*/ $Vsk Ew"|M
package com.adt.bo; sLh==V;9
t
c[n&X
import java.util.List; c?P?yIz6p
:iFIQpk
import org.flyware.util.page.Page; !
N|0x`
.e3NnOzyxS
/** %R1 tJ( /
* @author Joa L Y6;.d$J
*/ XXbqQhf
publicclass Result { ag$Vgl
C?ulj9=Z
private Page page; 1[kMOp
nYWvTvZ
private List content; ^?$WVB
HfcL%b%G8
/** _C.BFE_p
* The default constructor ^Y<|F!0
*/ FSU ttg"
public Result(){ qs|mj}?
super(); .7zK@6i
} OF%B[h&
?in|qevL
/** dX\.t<
* The constructor using fields "8'@3$>R=
* 3VuW#m#j
* @param page s?zAP O8Sz
* @param content /V=24\1Ky
*/ 6}75iIKi
public Result(Page page, List content){ ";BlIovT=R
this.page = page; 9V,!R{kO!
this.content = content; :*t"8;O[
} =81@o,1w
N+zKr/
/** :
m)
* @return Returns the content. Ib|Rf;J~-
*/ CL)lq)1(
publicList getContent(){ DKfE.p)
return content; :}r.
} uqM yoIc
YWMGB#=
/** |_}2f
* @return Returns the page. <F'X<Bau
*/ RlheQTJ
public Page getPage(){ G+F#n6Vx
return page;
:,WtR
} eFBeJZuE|
:`E8Z:-R
/** $p#%G#T
* @param content kgy:Q'
* The content to set. 4VHqBQ4
*/ ;^La"m
public void setContent(List content){
.w> 4
this.content = content; n"+[ :w4
} /R~1Zj2&
*4U^0e
/** Jo$G,Q
* @param page IGS1|
* The page to set. Dw=gs{8D
*/ wUiys/OVM
publicvoid setPage(Page page){ 3l[McZ
this.page = page; ?notxE7 ]
} :[\v
} %@;6^=
d}LR l" _n
w$H^q
!(
9Q(+ZG=JkV
5K^69mx
2. 编写业务逻辑接口,并实现它(UserManager, Na$Is'F&p
b8$gx:aJ>$
UserManagerImpl) CSGz3uC2D
java代码: ^Y u6w\QM
GM<BO8Y.
@mE)|.f
/*Created on 2005-7-15*/ af#pR&4}
package com.adt.service; ixW@7m
t|9 GS|
import net.sf.hibernate.HibernateException; %)[+%57{
Jg]'+>,J
import org.flyware.util.page.Page; o
}3uo6GIB
QU%I43
import com.adt.bo.Result; YX=2jI
+j(d| L\
/** "Vw m
* @author Joa t<T[h2Wd
*/ &FH2fMLQ
publicinterface UserManager { vo\fUT@k
2-=\~<)
public Result listUser(Page page)throws j<2m,~k`V
N2oRJ,:B
HibernateException; {GKy'/[
$&$w Y/F
} |}{B1A
Ubh{!Y
1QcT$8HA
gXonF'
GuGOePV
java代码: #VB')^d<U
AK=
h[2(
>$ NDv
/*Created on 2005-7-15*/ >*-FV{{
package com.adt.service.impl; lc2 i`MC
<&&SX;
import java.util.List; W%.v.0
j
[rB"N`0
import net.sf.hibernate.HibernateException; |,#t^'S!
rsF\JQk
import org.flyware.util.page.Page; J4"mK1N(
import org.flyware.util.page.PageUtil; -+7uy.@cS
?lbH02P{v
import com.adt.bo.Result; ;<$H)`*
import com.adt.dao.UserDAO; |o2sbLp
import com.adt.exception.ObjectNotFoundException; 7_.11$E=H
import com.adt.service.UserManager; ,g7.rEA
a-"k/P#
/** "V>R9dO{"!
* @author Joa q}/WQ]p} <
*/ uKz,SqX
publicclass UserManagerImpl implements UserManager { i
`s|,"0o
H;U)b{
private UserDAO userDAO; c&X{dJWD
o\88t){/kB
/** *[r!
* @param userDAO The userDAO to set. tG8jFou
*/ ~go
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publicvoid setUserDAO(UserDAO userDAO){ yfjK2
this.userDAO = userDAO; &K43x&mFF
} y.=/J8->
]c<qM_HWg
/* (non-Javadoc) ew;ur?
* @see com.adt.service.UserManager#listUser ]J* ,g,
\S*$UE]uG
(org.flyware.util.page.Page) cFN'bftH4
*/ |\dZ'
public Result listUser(Page page)throws kaxvPv1
!IC-)C,q
HibernateException, ObjectNotFoundException { bae\Zk%`^
int totalRecords = userDAO.getUserCount(); }<>~sy
if(totalRecords == 0) 1VF
throw new ObjectNotFoundException "+z?x~rk
K]qM~v<A
("userNotExist"); R64!>o"nED
page = PageUtil.createPage(page, totalRecords); T;diNfgg
List users = userDAO.getUserByPage(page); N7b1.]<
returnnew Result(page, users); OdQT2PA_
} Qd_Y\PzS
.MVY B\6Q0
} &n[~!%(
i\4hR?
KJ?y@Q
mAeuw7Ni
.fi/I
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 4<lQwV6=
BaO1/zk
询,接下来编写UserDAO的代码: Tzt ,/e
3. UserDAO 和 UserDAOImpl: [L6w1b,
java代码: ^9_UUzf\
/Y&02L%\3s
*d(SI<j
/*Created on 2005-7-15*/ '`|AI:L
package com.adt.dao; F,GN[f-
4D$;KokZ
import java.util.List; g|Y] wd
O<jPGU
import org.flyware.util.page.Page; {/LZcz[
WKrX,GF
import net.sf.hibernate.HibernateException; rZojY}dWJ
6cdMS[_SD(
/** FZ|CqD"#
* @author Joa yoRU_%xA
*/ N7%TYs
publicinterface UserDAO extends BaseDAO { rVtw-[p
TZ;p0^(
publicList getUserByName(String name)throws Uw/l>\
vBvNu<v7te
HibernateException; Olfn
oyk>vIZ
publicint getUserCount()throws HibernateException; <e)o1+[w
a`E*\O'd
publicList getUserByPage(Page page)throws _Cy:]2o
v)f7};"z
HibernateException; `_5GG3@Ff
cBYfXI0`
} Eq^uKi
v8/6wy?
TwvAj#j
a=xT(G0Re
pilh@#_h
java代码: EPX8Wwf
H@l}[hkP
F_ 7H!F
/*Created on 2005-7-15*/ 8ga_pNe
package com.adt.dao.impl; \OC6M` /
pO~c<d}b
import java.util.List; .>Z,uT^A
r7]"?#
import org.flyware.util.page.Page; mxFn7.|r~
1ndJ+H0H
import net.sf.hibernate.HibernateException; W3&tJ8*3
import net.sf.hibernate.Query; 'PlaM Oy
D H^T x
import com.adt.dao.UserDAO; "R9Yb,tIN
D);'pKl
/** m-V02's
* @author Joa .5> 20\b2
*/ Nf9fb?
public class UserDAOImpl extends BaseDAOHibernateImpl y69J%/c
ra
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implements UserDAO { ?@R")$
p|XAlia
/* (non-Javadoc) 8I+d)(:
* @see com.adt.dao.UserDAO#getUserByName g):]'
]Z4zF"@
(java.lang.String) R^MiP|?ZH
*/ C+K=[
publicList getUserByName(String name)throws Vv*NFJ |
T~gW3J
HibernateException { VY+>=!
String querySentence = "FROM user in class !asqr1/
5IqQ |/m<6
com.adt.po.User WHERE user.name=:name"; ]M,06P>?
Query query = getSession().createQuery wk\L* \@Y}
%do1i W
(querySentence); LH]CUfUrUE
query.setParameter("name", name); LD (C\
return query.list(); V/"}ku
} /&Jv,[2kV
z,*:x4}F
/* (non-Javadoc) ?M6ag_h3
* @see com.adt.dao.UserDAO#getUserCount() y/_wx(2
*/ vt]F U<
publicint getUserCount()throws HibernateException { }Ia 0"J4
int count = 0; H5nS%D
String querySentence = "SELECT count(*) FROM Y/U{Qc\6
ivrXwZ7jT
user in class com.adt.po.User"; %*)2s,8
Query query = getSession().createQuery W"hcaa,&
(:\LWJX0=
(querySentence); en9en=n|
count = ((Integer)query.iterate().next _$/
+D:K
IS]{}Y\3H
()).intValue(); gbOCR1PBg
return count; \gccQig1CJ
} QLbMPS
@qK<T
/* (non-Javadoc) ilEi")b=
* @see com.adt.dao.UserDAO#getUserByPage b; 9n'UX\
:kw0y
(org.flyware.util.page.Page) O|v
(58A
*/ J\W-dI
publicList getUserByPage(Page page)throws K]N~~*`%`
uhn%lV]
HibernateException { s` >H
String querySentence = "FROM user in class Q!CO0w
Ly(P=M>"y
com.adt.po.User"; @R:#"
Query query = getSession().createQuery f\ "`7
sm s1%%~
(querySentence); E`p'L!z
query.setFirstResult(page.getBeginIndex()) f =_^>>.
.setMaxResults(page.getEveryPage()); a&/HSf_G
return query.list(); t&c&KFK)I&
} 02 f9 w V
TGWdyIk
} (:$9%,x
EI`vVI
3-Y=EH_0
d><fu]'
mf 4z?G@6
至此,一个完整的分页程序完成。前台的只需要调用 `
%' z
Ao`_",E
userManager.listUser(page)即可得到一个Page对象和结果集对象 b>q6:=((
6S*zzJ.0K
的综合体,而传入的参数page对象则可以由前台传入,如果用 zW'/2W.
]G1R0 Q
webwork,甚至可以直接在配置文件中指定。 mC(u2
hhq$g{+[
下面给出一个webwork调用示例: nN{dORJlx
java代码: 1
Nk1MGV
bf98B4<
-h\@RC
/*Created on 2005-6-17*/ 'yT`ef
package com.adt.action.user; p~>_T7ze
{'(ej5,6
import java.util.List; DJ:38_ F
:Kay$r0+
import org.apache.commons.logging.Log; :QA@ c|(PF
import org.apache.commons.logging.LogFactory; ec?1c&E
import org.flyware.util.page.Page; \|{*arS
7t4v~'h;5e
import com.adt.bo.Result; w~v<v&
import com.adt.service.UserService; <;KRj85"j
import com.opensymphony.xwork.Action; u[`v&e
@f=RL)$|
/** vb}/@F,Q5
* @author Joa Qg>L,ZO
*/ cHn;}l!I
publicclass ListUser implementsAction{ _[$#
b]V
'oi2Seq
privatestaticfinal Log logger = LogFactory.getLog M'|)dM|
-><QFJ
(ListUser.class); O|(o8VS
ZKsQ2"8{M
private UserService userService; tMG@K
JTkCk~bX[z
private Page page; {F)E\)$G
^fZGX<fH
privateList users; D5[VK`4Z
n` #+L~X
/* z\h,SX<U
* (non-Javadoc) W8uVd zQ
* %QE5<2k
* @see com.opensymphony.xwork.Action#execute() 8DL hk
*/ 4^MSX+zt
publicString execute()throwsException{ z6}Pj>1
Result result = userService.listUser(page); %g-0O#8}
page = result.getPage(); LI:?Y_r
users = result.getContent(); ;x RjQR
return SUCCESS; Z]e4pR6!
} ~GYpat
45r|1<R o
/** 8v$g
* @return Returns the page. X o_] v
*/ =u[rOU{X"W
public Page getPage(){ |<QI%Y$dr
return page; wV
%8v\
} V4oak!}?
y$v@wb5
/** 7Ff?Ysr
* @return Returns the users. 1[[TB .xF
*/ hC|KH}aCR)
publicList getUsers(){ IKtiR8
return users; ~e+0c'n\
} IF$^0q
'@S,V/jy0z
/** )j(fWshP
* @param page B{N=0 cSi
* The page to set. haik
*/ w+3>DEfz
publicvoid setPage(Page page){ u,!4vKx
this.page = page; be_C>v
} @?j@yRe
)MMhlcNC
/** <Q\H
* @param users kYmo7
* The users to set. v s w7|
*/ O'@m4@L
publicvoid setUsers(List users){ rt,0j/o.1
this.users = users; ^$ 8Vh=D
} `Q+i-y
>9(7h&[Y
/**
=05iW
* @param userService w64.R4e
* The userService to set. A/hpYa
*/ S]5VEn;pV
publicvoid setUserService(UserService userService){ N!.kq4$.
this.userService = userService; rSzQUn<
} ja L$LJV
} @\S]]oLn
@yCW8]
P7cge
%
i%ew4
./';P<)
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, (v|ixa
p"g1V7B
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 D8q3TyCj%
)#)nBM2\
么只需要: ;K>{_kf
java代码: )A"ZV[eOoQ
kT>r<`rt
e!.7no
<?xml version="1.0"?> rL.<Z@-
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ^l&nB