Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 6"=e+V@
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 m[8#h(s*t
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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 |w>DZG!}1-
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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 (PB|.`_<H
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。 )8N/t6Q
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分页支持类: #pVk%5N
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java代码: Q;^([39DI
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package com.javaeye.common.util; Lh,<q
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import java.util.List; Em?skUnG,
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publicclass PaginationSupport { k1cBMDSokO
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publicfinalstaticint PAGESIZE = 30; gM=~dBz
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privateint pageSize = PAGESIZE; y1AS^'
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privateList items; >H%8~ Oek
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privateint totalCount; nh8h?&q|
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privateint[] indexes = newint[0]; 6zI?K4o
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privateint startIndex = 0; L NE]#8ue
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public PaginationSupport(List items, int 6Q>w\@lF
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totalCount){ vLC&C-f
setPageSize(PAGESIZE); zzx4;C",u
setTotalCount(totalCount); [NFAdE
setItems(items); v>e4a/
setStartIndex(0); +HcH]D;
} m[7a~-3:J
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public PaginationSupport(List items, int R.fRQ>rI
. =+7H`A
totalCount, int startIndex){ zZ wD)p?_g
setPageSize(PAGESIZE); CkflEmfe
setTotalCount(totalCount); #&/*ll)
setItems(items); -^Lj~O
setStartIndex(startIndex); Gmc"3L
} yZ P+
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public PaginationSupport(List items, int p;H1,E:Re#
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totalCount, int pageSize, int startIndex){ Op0
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setPageSize(pageSize); :V"}"{(6
setTotalCount(totalCount); ht-6_]+ME
setItems(items); kOjq LA
setStartIndex(startIndex); qI"mW@G~H
} (sl~n_<ds8
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publicList getItems(){ C/w;g3
return items; ~Ch`A@=5
} JxWHrsh[
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publicvoid setItems(List items){ I2Us!W>6-
this.items = items; [_~U<
} )I<.DN&
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publicint getPageSize(){ z/ i3
return pageSize; ,=ICSS~9l
} Vz#cb5:g
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publicvoid setPageSize(int pageSize){ y^XwJX-f
this.pageSize = pageSize; -cW5v
} ~9n@MPS^!
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publicint getTotalCount(){ b
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return totalCount; 4VooU [Ka(
} qzLRA.#f^
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publicvoid setTotalCount(int totalCount){ (0][hdI~B
if(totalCount > 0){ r9%W?fEBp
this.totalCount = totalCount; _Nj;Ni2rD
int count = totalCount / "K@os<
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pageSize; W,<Vr2J[
if(totalCount % pageSize > 0) m&x0,8
count++; vZKo&jUk
indexes = newint[count]; Jk~T.p?tF
for(int i = 0; i < count; i++){ "pH+YqJ$
indexes = pageSize * qB&*"gf
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i; j4l7Tx
} (I+-wki"e
}else{ x|Ei_hI-
this.totalCount = 0; x;SrJVDN
} 4*54"[9Hr#
} B|%;(bM2C
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publicint[] getIndexes(){ ?e@Ff"Y@e
return indexes; FHD6@{{Gp"
} WFB2 Ub7
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publicvoid setIndexes(int[] indexes){ qV}zV\Nz
this.indexes = indexes; _3E7|drIX
} L.GpQJ8u
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publicint getStartIndex(){ YF"D;.
return startIndex; *<UQ/)\
} 0 #q_LB
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publicvoid setStartIndex(int startIndex){ "&r1&StO
if(totalCount <= 0) o1Xk\R{
this.startIndex = 0; m$o|s1t
elseif(startIndex >= totalCount) hsl8@=_ B
this.startIndex = indexes Jd%#eD*k9
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[indexes.length - 1]; \<PW_'6
elseif(startIndex < 0) 6^zv:C%
this.startIndex = 0; LJiMtqg
else{ USbiI%
this.startIndex = indexes 06ueE\@Sg
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[startIndex / pageSize]; v-l):TL+=
} DB*IVg
} 0VbZBLe
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publicint getNextIndex(){ #mj+|/0
int nextIndex = getStartIndex() + :4WwCpgz,
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pageSize; x,>=X`T
if(nextIndex >= totalCount) ="u(o(j"
return getStartIndex(); uM\~*@
else x=H*"L=
return nextIndex; c)lK{DC
} p#?1l/f"
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publicint getPreviousIndex(){ ~@-Az([H
int previousIndex = getStartIndex() - A$
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pageSize; Og,,s{\
if(previousIndex < 0) U,]z)1#X|
return0; 9 ROKueP
else ~MXPiZG?
return previousIndex; H7{ 6t(0j
} -aO3/Ik[q
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} jf})"fz-*
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抽象业务类 pa+y(!G
java代码: 6 o+zhi;E
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/** +J^}"dG
* Created on 2005-7-12 LAr6J
*/ F"bbU/5
package com.javaeye.common.business; ")LF;e
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import java.io.Serializable; 1di?@F2f
import java.util.List; }vm17`Gfy
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import org.hibernate.Criteria; E7*]t_p"
import org.hibernate.HibernateException; yEz2F3[ S
import org.hibernate.Session; NfN#q:w1
import org.hibernate.criterion.DetachedCriteria; $GYy[-.`
import org.hibernate.criterion.Projections; ]];7ozS)X
import 31_5k./
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org.springframework.orm.hibernate3.HibernateCallback; #-kyZ
import 7?kvrIuY&
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org.springframework.orm.hibernate3.support.HibernateDaoS Z1>pOJm
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upport; x
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import com.javaeye.common.util.PaginationSupport; 2S/^"IM["
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public abstract class AbstractManager extends 6L*y$e"Qc
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HibernateDaoSupport { iBc(
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privateboolean cacheQueries = false; 8..itty
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privateString queryCacheRegion; IP~g7`Y
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publicvoid setCacheQueries(boolean )JZfC&,
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cacheQueries){ fCTjTlh
this.cacheQueries = cacheQueries; D}_\oE/n
} -Y+[`0$'
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publicvoid setQueryCacheRegion(String #7g~Um%p
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queryCacheRegion){ S4tdWA
this.queryCacheRegion = zKI(yC
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queryCacheRegion; xxedezNko
} kDm=Cjxv
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publicvoid save(finalObject entity){ ]{;K|rCR-
getHibernateTemplate().save(entity); ]r#tJT`M
} bb#w]!q
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publicvoid persist(finalObject entity){ 6%5A&&O(b
getHibernateTemplate().save(entity); @5kN
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} 9,F(f}(t
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publicvoid update(finalObject entity){ qg'm<[
getHibernateTemplate().update(entity); m@yaF:
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} K J~f ~2;
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publicvoid delete(finalObject entity){ Bg34YmZ
getHibernateTemplate().delete(entity); 1ra}^H}
} HM<V$
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publicObject load(finalClass entity, ukZL
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finalSerializable id){ 6vmkDL8{A8
return getHibernateTemplate().load ?B[Z9Ef"8l
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(entity, id); /.}&yRR
} )ll}hGS
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publicObject get(finalClass entity, )}/9*
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finalSerializable id){ xo?f90+(
return getHibernateTemplate().get fE M8/bhq
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(entity, id); Q PGssQR6
} 2o{Fp7l
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publicList findAll(finalClass entity){ ofN|%g /
return getHibernateTemplate().find("from AU)Qk$c
&;,w})
" + entity.getName()); Z|3l2ucl
} bluC P|
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publicList findByNamedQuery(finalString C
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namedQuery){ jd~r~.y
return getHibernateTemplate o6svSS
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().findByNamedQuery(namedQuery); *S;v406
} &
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publicList findByNamedQuery(finalString query, 3"q%-M|+Q
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finalObject parameter){ -V<i4X<|,+
return getHibernateTemplate &?x^I{j
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().findByNamedQuery(query, parameter); v6iV#yz3(
} D<nTo&m_
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publicList findByNamedQuery(finalString query, ;g?5V
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finalObject[] parameters){ lK}F>6^\
return getHibernateTemplate eZf-i1lJ
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().findByNamedQuery(query, parameters); _Z2VS"yH
} }Z2Y>raA\
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publicList find(finalString query){ `Ol*"F.+I
return getHibernateTemplate().find IDcu#Nz`
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(query); -6Cxz./#yS
} JTdK\A>l
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publicList find(finalString query, finalObject "i9$w\lm
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parameter){ wGw}a[a
return getHibernateTemplate().find F4d L{0;j
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(query, parameter); t t#M4n@
} g_.BJ>Uv
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public PaginationSupport findPageByCriteria U<o,`y[Tn
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(final DetachedCriteria detachedCriteria){ ,]Hn*\@p[c
return findPageByCriteria l6)*u[}E
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); TB1 1crE
} {s4:V=J
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public PaginationSupport findPageByCriteria <L:v2 8c
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(final DetachedCriteria detachedCriteria, finalint {8b6A~/
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startIndex){ `N2zeFG
return findPageByCriteria 4uDz=B+8y
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(detachedCriteria, PaginationSupport.PAGESIZE, AY|8wf,LS
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startIndex); jr'O4bo%
} ^d-`?zb
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public PaginationSupport findPageByCriteria 7nfQ=?XNK
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(final DetachedCriteria detachedCriteria, finalint v-&^G3
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pageSize, 4B!]%Mw;c
finalint startIndex){
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return(PaginationSupport) Rl<~:,D
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getHibernateTemplate().execute(new HibernateCallback(){ tNfku
publicObject doInHibernate kXv
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(Session session)throws HibernateException { %p@A8'b
Criteria criteria = 5ahAp];
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detachedCriteria.getExecutableCriteria(session); l$MX\
int totalCount = Ij/c@#q.
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((Integer) criteria.setProjection(Projections.rowCount \)`\F$CF
42
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()).uniqueResult()).intValue(); =<R77rnY&
criteria.setProjection V=.lpj9m
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(null); naM4X@jl
List items = +g\u=&<6
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criteria.setFirstResult(startIndex).setMaxResults xlS
t
~ia#=|1}
(pageSize).list(); a)[t kjU
PaginationSupport ps = 0;r+E*`DA
- C8h$P
new PaginationSupport(items, totalCount, pageSize, (F~eknJ
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startIndex); prhFA3
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return ps; 8_m dh +
} ^MDBJ0
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}, true); ) Q]kUG#`
} Pgs4/
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public List findAllByCriteria(final \O72PC+
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DetachedCriteria detachedCriteria){ B1J+`R3OX
return(List) getHibernateTemplate
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().execute(new HibernateCallback(){ N]} L*o&
publicObject doInHibernate h`?0=:Tru
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(Session session)throws HibernateException { ,$7LMTVDrE
Criteria criteria = e2k!5OS
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detachedCriteria.getExecutableCriteria(session); 3-~_F*%ST
return criteria.list(); ]:Ocu--
} 23&;28)8
}, true); {Km|SG[-q
} XR]]g+Z
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public int getCountByCriteria(final +TA(crD
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DetachedCriteria detachedCriteria){ JKGUg3\~
Integer count = (Integer) <iv9Mg}
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getHibernateTemplate().execute(new HibernateCallback(){ =}u;>[3
publicObject doInHibernate Ui'~d(F
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(Session session)throws HibernateException { 5{[3I|m{
Criteria criteria = .V
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detachedCriteria.getExecutableCriteria(session); rOS fDv
return zxTm`Dh;[
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criteria.setProjection(Projections.rowCount U~!97,|ic
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()).uniqueResult(); uWv l<{2
} nakhepLN
}, true); uA*Op45
return count.intValue(); N{L ]H_=
} E&GUg/d
} 5rfGMk<
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用户在web层构造查询条件detachedCriteria,和可选的 3eFD[c%mN
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Jel%1'Dc^
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PaginationSupport的实例ps。 m-7^$
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ps.getItems()得到已分页好的结果集 z| i$eF;x3
ps.getIndexes()得到分页索引的数组 HC+(FymV
ps.getTotalCount()得到总结果数 $BkdC'D
ps.getStartIndex()当前分页索引 ,dK% [
ps.getNextIndex()下一页索引 G2
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ps.getPreviousIndex()上一页索引 E!C~*l]wJx
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 FV!
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 @fPiGu`L
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一下代码重构了。 OBF5Tl4
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我把原本我的做法也提供出来供大家讨论吧: #oJ9BgDry
akrEZ7A
首先,为了实现分页查询,我封装了一个Page类: ,Es5PmV@$%
java代码: I]jVnQ>&
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/*Created on 2005-4-14*/ J[RQF54qA{
package org.flyware.util.page; O9:vPbn
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/** !N?|[n1
* @author Joa `b# w3 2
* Bn-%).-ED
*/ Zb<DgJ=3
publicclass Page { SN\;&(?G
=DcKHL(m
/** imply if the page has previous page */ P;mmK&&
privateboolean hasPrePage; )7*Apy==x
f)?s.DvUB
/** imply if the page has next page */ po\Q Me
privateboolean hasNextPage; Z:u7`%
AIN_.=]"?
/** the number of every page */ ~^KemwogPN
privateint everyPage; [;h@q}
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/** the total page number */ i*nNu-g
privateint totalPage; !NZFo S~
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/** the number of current page */ fL'
42
privateint currentPage; y3))I\QT
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/** the begin index of the records by the current +c+#InsY
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query */ H [R|U
privateint beginIndex; ^Me__Y
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/** The default constructor */ :
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public Page(){ CP["N(fF
bUU_NqUf*3
} `+Wl
fk;
.
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/** construct the page by everyPage jbMzcn~ehI
* @param everyPage pn{Nk1Pl
* */ 6]CY[qEaR$
public Page(int everyPage){ +*lSB%`aS
this.everyPage = everyPage; 1g^N7YF
} ro|dB
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/** The whole constructor */ %dhnp9'
public Page(boolean hasPrePage, boolean hasNextPage, X3<<f`X
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n;/yo~RR
int everyPage, int totalPage, )Uo)3FAn
int currentPage, int beginIndex){ wRi!eN?
this.hasPrePage = hasPrePage; -]A,SBs
this.hasNextPage = hasNextPage; GbBcC#0
this.everyPage = everyPage; bt-y6,> +E
this.totalPage = totalPage; u4rG e!
this.currentPage = currentPage; 'HH[[9Q
this.beginIndex = beginIndex; zxT&K|
} u\Tq5PYXt
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/** e#<%`\qH
* @return ikw_t?
* Returns the beginIndex. O{%yO=`r
*/ 4$@5PS#,
publicint getBeginIndex(){ 118A6qyi
return beginIndex; rB<
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} EO:i+e]=
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/** W(9-XlYKE
* @param beginIndex
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* The beginIndex to set. gY=nU,;
*/ 3.xsCcmP
publicvoid setBeginIndex(int beginIndex){ qVx4 t"%L>
this.beginIndex = beginIndex; rMdOE&5G
} gcQ>:mi
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/** ;Ze}i/l
* @return OLXG0@
* Returns the currentPage. ,1a6u3f,
*/ 18zv]v
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publicint getCurrentPage(){ 1I<fp $h
return currentPage; u?&P6|J&
} S)>L 0^M1
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/** [K9l>O
* @param currentPage p>Qzz`@e
* The currentPage to set. -V%"i,t
*/ )4bBR@QM
publicvoid setCurrentPage(int currentPage){ s%1 O}X$c
this.currentPage = currentPage; qm{(.b^
} ^"(CZvq
+>M^p2l*&
/** |'aGj
* @return Vof[yL `
* Returns the everyPage. [h
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*/ V<*PaS..
publicint getEveryPage(){ |~Z.l
return everyPage; )CD4k:bm
} (1^AzE%U+Z
@/9#Z4&d0
/** I~-W4{
* @param everyPage x&@. [FJhO
* The everyPage to set. TMpV.iH
*/ 1I{vBeMj
publicvoid setEveryPage(int everyPage){ |Rd?s0u
this.everyPage = everyPage; -r@fLkwg
} yT.h[yv"w
wDVKp['
/** %iPWg
* @return V|13%aE_v
* Returns the hasNextPage. G3
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*/ YC8wo1;Y!
publicboolean getHasNextPage(){ J<'[P$D
return hasNextPage; lmi,P-Q
} z"Miy
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/** 1hp`.!3]H
* @param hasNextPage ?#YheML?
* The hasNextPage to set. :PE{2*
*/ Tvqq# ;I
publicvoid setHasNextPage(boolean hasNextPage){ WYSqnmi
this.hasNextPage = hasNextPage; opU=49b
} |r>+\" X
7 XE&[o
/** NvW`x
* @return 6<u=hhL
* Returns the hasPrePage. [ uU"=H|
*/ kVz9}Xp"
publicboolean getHasPrePage(){ Yd'Fhvo8
return hasPrePage; mvgsf(a*'
} Tsch:r S
n=J~Rssp
/** (H5nz':
* @param hasPrePage Iv+JEuIi
* The hasPrePage to set. ,h,OUo]LIY
*/ iO 9.SF0:
publicvoid setHasPrePage(boolean hasPrePage){ 6?$yBu9l
this.hasPrePage = hasPrePage; UTB]svC'
} 9:
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= >CADTU
/** M(8dKj1+
* @return Returns the totalPage. { RH&mu
* [U]^:sV)
*/ QxS]6hA
publicint getTotalPage(){ w"ZngrwBl
return totalPage; ndg1E;>
} S52'!WTq
VzD LG LH
/** J_NY:B
* @param totalPage '2Q[g0VR
* The totalPage to set. u_H=Xm)9
*/ Z*/{^ zsE
publicvoid setTotalPage(int totalPage){ -Pt.
this.totalPage = totalPage; \]<eLw-v
} *U>"_h T0
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} fE`p
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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 3 @a hN2
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个PageUtil,负责对Page对象进行构造: 'F2g2W`
java代码: ^Gi9&fS,
3PkVMX
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/*Created on 2005-4-14*/ wnUuoX(
package org.flyware.util.page; ,5V w^@F
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import org.apache.commons.logging.Log; Ey|{yUmU+
import org.apache.commons.logging.LogFactory; &3gC&b^i
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/** _D+pJ{@W
* @author Joa gy5 ^JL
* GmhfBW?
*/ P* X^)R
publicclass PageUtil { f/xQy}4+~E
i4T=4q
privatestaticfinal Log logger = LogFactory.getLog n( RQre
`PY=B$?{4
(PageUtil.class); FEY_(70
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/** uA-1VwW+N
* Use the origin page to create a new page RN^<bt{_U
* @param page nA*Udrcn
* @param totalRecords 4y*"w*L
* @return Nk63F&J7e
*/ (aC~0
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publicstatic Page createPage(Page page, int `D/<*e,#
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totalRecords){ =[JstiT?E
return createPage(page.getEveryPage(), l XpbAW
uB=DC'lkg
page.getCurrentPage(), totalRecords); t=nZ1GZyM
} 8k{KnH
Mi~x(W@}3
/** :+_uyp2V
* the basic page utils not including exception e"#QUc(
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handler +Y?)?
* @param everyPage bG)EZ
* @param currentPage o$QC:%[#
* @param totalRecords A"tE~m;"7
* @return page o5B]? ekpq
*/ 6Y`rQ/F
publicstatic Page createPage(int everyPage, int 7Pe<0K)s(
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currentPage, int totalRecords){
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everyPage = getEveryPage(everyPage); ;!S i_b2
currentPage = getCurrentPage(currentPage); @.&KRAZ
int beginIndex = getBeginIndex(everyPage, shgZru
;
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currentPage); A)#w~ X4
int totalPage = getTotalPage(everyPage, o 9rZ&Q<
sU(<L0
totalRecords); a B$x(8pP@
boolean hasNextPage = hasNextPage(currentPage, DD5cUlOSu
LpK? C<?x
totalPage); >P+oNY
boolean hasPrePage = hasPrePage(currentPage); %i6/=
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returnnew Page(hasPrePage, hasNextPage, l{I.l
everyPage, totalPage, /IQ$[WR cx
currentPage, |&"/u7^
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beginIndex); 6t\0Ui
} G%A!yV
enGZb&
privatestaticint getEveryPage(int everyPage){ ~9y/MR
return everyPage == 0 ? 10 : everyPage; 9!_JV;2
} r^7eK)XA_
_z=ytt9D
privatestaticint getCurrentPage(int currentPage){ YEa<zhO8
return currentPage == 0 ? 1 : currentPage; B/*\Ih9y
} s
!IvUc7'
8e5imei
privatestaticint getBeginIndex(int everyPage, int }<qZXb1
CwM1
_3cE
currentPage){ p;qFMzyS9
return(currentPage - 1) * everyPage; wpWZn[j
} C2CR#b=)i
{[4.<|26
privatestaticint getTotalPage(int everyPage, int Up1n0
llN/
totalRecords){ x4i&;SP0
int totalPage = 0; \kZ@2.pN
$."DOZQ3U
if(totalRecords % everyPage == 0) ekW#|
totalPage = totalRecords / everyPage; n8E3w:A-
else +B[XTn,Cru
totalPage = totalRecords / everyPage + 1 ; Q#F9&{'l
Aj8zFt]
return totalPage; ]eUD3WUe>q
} 4T6: C?V
0GW69 z
privatestaticboolean hasPrePage(int currentPage){ 5yyc0UG
return currentPage == 1 ? false : true; F}.R-j#
} ;}lsD1S:
Q@"}v_r4
privatestaticboolean hasNextPage(int currentPage, )<%CI#s#
^-LnO%h?
int totalPage){ n&!q9CR`
return currentPage == totalPage || totalPage == ~Ede5Vg!!2
#@' B\!<@=
0 ? false : true; JXjH}C
} T/0cPn0>
U;A,W$<9
O=eU38n:5u
} Kum" }ux
^M1jv(
Uw]o9 e0S
t7yvd7
Py?e+[cN
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。 |{ =Jp<}s
I s|_
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ~ z^49Ys:
;?q-]J?
做法如下: j115:f
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 9K;g\? 3
F~0iJnF
的信息,和一个结果集List:
M6ZXq6J
java代码: >;]S+^dXY
Hh%"
p1[|5r5Day
/*Created on 2005-6-13*/ k0&FUO
package com.adt.bo; 2Jky,YLcb
]*U+nG
import java.util.List; #)m[R5g(
Em4'b1mDX%
import org.flyware.util.page.Page; H?eG5
2c51kG77E
/** DxD\o+:r
* @author Joa lD'^6
*/ mE;^B%v
publicclass Result { !u:Fn)j
d}
5
private Page page; A#{I-*D[
pI.~j]*:{
private List content; ^hsr/|
G*=&yx."E
/** KzX)6|g{"
* The default constructor i03=Af3
*/ mq}UUk@
public Result(){ uP$i2Cy
super(); c_,pd
} d04gmc&*
zJh!Q**
/** $WE=u 9m
* The constructor using fields r oPC
^Q
* PT~F^8,)
* @param page oB @)!'
* @param content cuI&Q?+c}
*/ A6+qS
[
public Result(Page page, List content){ QCG-CzJ9l
this.page = page; ;dtA-EfOZ
this.content = content; fLeHn,*,"
} q,_EHPc
N?8nlrDQ
/** bl^pMt1fv
* @return Returns the content. 'K}2 m
*/ 3DxgfP%n
publicList getContent(){ WZjR^6
return content; oCLM'\
} <(~Wg{
vXZP>
/** ?%%vQ?
* @return Returns the page. 3g:P>(
*/ ]k BC,m(
public Page getPage(){ t0Lt+E|J
return page; N"0>)tG
} gK"(;Jih$
<IBUl}|\
/** *y(UI/c
* @param content dQFUQ
* The content to set. Pf;RJeD
*/ `Ba?4_>k
public void setContent(List content){ )iVuac]E++
this.content = content; TwF.UL@G%
} [,;O$j}
ONZ(0H{ 1$
/** ~]Av$S
* @param page Bs|#7mA[
* The page to set.
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*/ @$CPTv3e
publicvoid setPage(Page page){ KZ1m2R}'
this.page = page; *v: .]_;
} 6ZwQ/~7H
} nEP3B'+
_mQj=
DjiI*HLNR
il"pKQF
R7;X
2. 编写业务逻辑接口,并实现它(UserManager, |Bv,*7i&
EP90E^v^
UserManagerImpl) $VP\Ac,!
java代码: /Z~$`!J
EMxMJ=
>]A#_p
/*Created on 2005-7-15*/ >6W #v[
package com.adt.service; 7Bd=K=3u
n
4cos
import net.sf.hibernate.HibernateException; HX,i{aWWy
~0o>B$xJ
import org.flyware.util.page.Page; IFZw54
56u_viZ=8
import com.adt.bo.Result; ~9,Fc6w4`+
sHV?njZd
/** loHMQKy@
* @author Joa \4
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*/ `,Y3(=3Xe?
publicinterface UserManager { ZN&9qw*
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public Result listUser(Page page)throws XeslOsHh
%sPq*w.
HibernateException; $Y\7E/T
%Na`\`L{F
} cBU3Q<^
hBifn\dFr
'c]Pm,Ls
9l |*E
Ls3r( Tf
java代码: &m]jYvRc
;?TM_%>
Z.rhM[*+0C
/*Created on 2005-7-15*/ >z%WW&Z'
package com.adt.service.impl; c+O:n:L
I]pz3!On4,
import java.util.List; |Ho}
D~
5{IbKj|
import net.sf.hibernate.HibernateException; w'y,$gtX/
k!x`cp
import org.flyware.util.page.Page; aWP9i&
import org.flyware.util.page.PageUtil; g5x>}@ONq7
<(xro/
import com.adt.bo.Result; S!^I<#d K
import com.adt.dao.UserDAO; x^cJ~e2
import com.adt.exception.ObjectNotFoundException; Fiw^twz5
import com.adt.service.UserManager; B5R 7geC
?%D nIl>
/** Gv[(0
* @author Joa Y:Jgr&*,z
*/ P?jI:'u!R.
publicclass UserManagerImpl implements UserManager { NF-@Q@
eOfVBF<C2
private UserDAO userDAO; J$T(p%
G,1g~h%I$
/** F7]8*[u
* @param userDAO The userDAO to set. Cy)QS{YX
*/ zyt >(A1
publicvoid setUserDAO(UserDAO userDAO){ ?iamo.0zN
this.userDAO = userDAO; >7cDfv"
} E}#&2n8Y
LWN9 D
/* (non-Javadoc) ;E!] /oY<
* @see com.adt.service.UserManager#listUser YM.
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(org.flyware.util.page.Page) Id>I.e4
*/ Kw:%B|B<T
public Result listUser(Page page)throws /1bQ
RI^\
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HibernateException, ObjectNotFoundException { )t:8;;W@Ir
int totalRecords = userDAO.getUserCount(); 2r]o>X
if(totalRecords == 0) :2XX~|
throw new ObjectNotFoundException sv#b5,>9
WD*z..`
("userNotExist"); WY5HmNX3E
page = PageUtil.createPage(page, totalRecords); 6uk}4bdvq
List users = userDAO.getUserByPage(page); TQ%F\@"
returnnew Result(page, users); %ZDO0P !/
} ~~m(CJ4S
=8"xQ>D62
} ~0}d=d5g
^7t1'A8e<
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 m6A\R KJ'
6.[3N~pq
询,接下来编写UserDAO的代码: HXPq+
3. UserDAO 和 UserDAOImpl: R+=wSG ]
java代码: ~8-xj6^
$'::51
CAN1~
/*Created on 2005-7-15*/ nV8iYBBym
package com.adt.dao; ,s:viXk
h}DKFrHW;-
import java.util.List; S&D8Rao5
x`2du/
C
import org.flyware.util.page.Page; SDk^fTV8x
,e
GF~
import net.sf.hibernate.HibernateException; ,# %I$
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/** VtGZB3
* @author Joa `lt[Q>Z
*/ : JSuC
publicinterface UserDAO extends BaseDAO { kE[R9RS!
,pVe@ d'
publicList getUserByName(String name)throws $H&:R&Us
Pa$"c?QUy
HibernateException; ::-*~CH)
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publicint getUserCount()throws HibernateException; ;Sp/N4+
hf7[<I,jov
publicList getUserByPage(Page page)throws +%K~HYN
IlB*JJnl
HibernateException; K}'?#a(aX=
+Y$EZL.A
}
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_c}# f\ +_
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HK%W7i/k@
j[dgY1yE:
java代码: )l`VE_(|
0ZZ Wj%
2@I0p\a
/*Created on 2005-7-15*/ J6<O|ng::
package com.adt.dao.impl; /Ba/gq0j
vTIRydg2b
import java.util.List; t
>.=q:
. lNf.x#u
import org.flyware.util.page.Page; EG3u)}vI
Ynp#3 r
import net.sf.hibernate.HibernateException; 0]^gT'
import net.sf.hibernate.Query; o%0To{MAF-
oa`7ClzD
import com.adt.dao.UserDAO; ~@T`0W-Py
i)$<j!L
/** Wv~&Qh}
* @author Joa
b #Llu$
*/ Lg|d[*;'7
public class UserDAOImpl extends BaseDAOHibernateImpl jvo^I$|2h
o8NRu7@?
implements UserDAO { 9n"MNedqH
)CgH|z:=b
/* (non-Javadoc) imKMPO=
* @see com.adt.dao.UserDAO#getUserByName <Pi#-r.,
.1_kRy2*.
(java.lang.String) M|{NC`fa
*/ 0s RcA -9
publicList getUserByName(String name)throws jdx T662q
Dv&K3^~Rfb
HibernateException { p%K(dA
String querySentence = "FROM user in class rj4R/{h
w6pXF5ur>
com.adt.po.User WHERE user.name=:name"; ff~1>=^
Query query = getSession().createQuery w"?RbA
LC\U6J't1
(querySentence); Z9Z\2t
query.setParameter("name", name); !0F+qzGG7
return query.list(); G^eXJusOv
} *dPbV.HCl
81w"*G5AM
/* (non-Javadoc) _KkP{g,Y
* @see com.adt.dao.UserDAO#getUserCount() xV=Tmu6l
*/ {-%8RSK=<
publicint getUserCount()throws HibernateException { z%\&n0
int count = 0; ?/myG{E
String querySentence = "SELECT count(*) FROM %E"Z &_3{
;|:R*(2
user in class com.adt.po.User"; ? PpS4Rd
Query query = getSession().createQuery e*U6^Xex
1+YqdDqQ
(querySentence); P+QL||>L
count = ((Integer)query.iterate().next `PSjkF(
Xg*](>/\,
()).intValue(); aPQxpK?
return count; qv'w 7T
} l[rK)PM
I0!]J{
/* (non-Javadoc) <1
;pyw
y
* @see com.adt.dao.UserDAO#getUserByPage e+MQmWA'F
yrd1J$
(org.flyware.util.page.Page) C7DwA/$D
*/ .8T0OQ4
publicList getUserByPage(Page page)throws ]'-y-kqY
vo%"(!
HibernateException { IDL0!cF
String querySentence = "FROM user in class v G9>e&Be
7R# }AQ
com.adt.po.User"; HxcL3Bh$~}
Query query = getSession().createQuery `*D"=5G+
m;t&P58f
(querySentence); 8_"NF%%(n
query.setFirstResult(page.getBeginIndex()) (OA4H1DL^
.setMaxResults(page.getEveryPage()); U3Z-1G~*r
return query.list(); kg\8 (@h]
} t[@>u'YKt
\O\q1
s~
} l5\V4
QHc([%oV
"F6gV;{Bt
K<kl2#
P,F
eF'J^
至此,一个完整的分页程序完成。前台的只需要调用 -4P `:bF
{8oGWQgrj
userManager.listUser(page)即可得到一个Page对象和结果集对象 1ANb=X|hig
b6p'%;Y/
的综合体,而传入的参数page对象则可以由前台传入,如果用 , 2xv
lW|v_oP9
webwork,甚至可以直接在配置文件中指定。 Aa4Tq2G
j4+Px%sW
下面给出一个webwork调用示例: JodD6;P
java代码: Ks@cwY
s~9n13z
QR _h#N2h
/*Created on 2005-6-17*/ 1j:aGj>{
package com.adt.action.user; VCJOWUEO1
}lT;?|n:h
import java.util.List; .{} 8mFi1
Gh@~~\
import org.apache.commons.logging.Log; i];P!Gm
import org.apache.commons.logging.LogFactory; @BF1X.4-+
import org.flyware.util.page.Page; KROD(
#<ST.f@*
import com.adt.bo.Result; yMTO 5~U{
import com.adt.service.UserService; `48Ql
import com.opensymphony.xwork.Action; Y]](.\ff
}a.j~>rq
/** zn7)>cQ905
* @author Joa bI8uw|c
*/ %OHZOs
publicclass ListUser implementsAction{ %.?V\l
E)ZL+(
privatestaticfinal Log logger = LogFactory.getLog /jGV[_Q=P
>#k-
~|w
(ListUser.class); ^YropzHZ4E
&i.sSqSI5
private UserService userService; 7GWOJ^)
7CvBE;i
private Page page; Qh(X7B
FROC/'
privateList users; >%0$AW|Exu
_B&Lyg!J
/* !!H"B('m
* (non-Javadoc) (xRcG+3];
* : -d_
* @see com.opensymphony.xwork.Action#execute() :dAd5v2f
*/ q!?*M?Oz
publicString execute()throwsException{ W)/^*,
Q7
Result result = userService.listUser(page); "Y=`w,~~
page = result.getPage(); T'@+MA) ~
users = result.getContent(); >m..
return SUCCESS; oPM*VTMA
} 13`Mt1R
|K06H
?6X
/** Zd-6_,r
* @return Returns the page.
2wHbhW[
*/ y& 1@d+Lf
public Page getPage(){ ?1a9k@[t
return page; ne/JC(
} Jk6}hUH,
\m
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/** ;'= cNj
* @return Returns the users. oSC'b%
*/ -4&
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publicList getUsers(){ NX.xEW@
return users; %&|
uT
} R]iV;j|
!W9:)5^X
/** `+"(GaZ
* @param page +ovK~K$A
* The page to set. *^~
=/:
*/ (Y@T5-!D
publicvoid setPage(Page page){ $?G@ijk,
this.page = page; ElV!C}g
} 5;U Iz@BJ
"8{A4N1B5
/** }:
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* @param users n]ba1t8ZA
* The users to set. '=n?^EPE3
*/ g}xL7bTlI>
publicvoid setUsers(List users){ Oo}h:3?
this.users = users; pB8D
} /uj^w&l#
*}d N.IL,
/** J-5>+E,nZ
* @param userService 8Auek#[
* The userService to set. ,0. kg
*/ yJq< &g
publicvoid setUserService(UserService userService){ aQtd6L+ J
this.userService = userService; @wI>0B
} VNHceH
} R[a-"
At4\D+J{Vs
1x:W 3.
\}s/<Q
!i^"3!.l,]
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, 2Lf,~EV
D=TS IJ@
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 T8x)i\<
Og/aTR<;=
么只需要: $`E?=L`$
java代码: q[,p#uJ]
yu6{ 6[
O -1O@:}c
<?xml version="1.0"?> J**(7d
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork =cS&>MT
jtP*C_Scv/
1.0//EN" "http://www.opensymphony.com/xwork/xwork- :ZV|8xI
ERpAV-Zf
1.0.dtd"> _SAM8!q4,
,X4+i8Yc
<xwork> [-])$~WfW
w={q@.
g%
<package name="user" extends="webwork- o@e/P;E
%N*[{j= ^
interceptors"> i[!|0U`p
J rx^
<!-- The default interceptor stack name )8@-
$nO~A7
--> mH&7{2r
<default-interceptor-ref r ;RYGLx
4,I,f>V
name="myDefaultWebStack"/> H9/!oI1P?
)S g6B;CJ
<action name="listUser" D_DwP$wSo
ub-3/T
class="com.adt.action.user.ListUser"> [a2]_]E%
<param b>;?{
| ys5.|
name="page.everyPage">10</param> H5}61 JC/z
<result 'f\9'v
g"m'
C6;
name="success">/user/user_list.jsp</result> K ze?@*
</action> fp' '+R[
}=[p>3Dd
</package> _ ;j1g%
8tx*z"2S
</xwork> *[Z`0AgP
DM^0[3XuV5
R| ?Q&F_$
~~W.]>f
djdTh
+>28
$oBs%.Jp
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 >Ku4Il+36
:?6HG_9X
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。 ~)U50.CH
&n6{wtBP
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Z<nNk.G
lYG`)#T
NN*L3yx
jIubJQR~
<fvu)
f
我写的一个用于分页的类,用了泛型了,hoho Nw*<e ]uD
W"c\/]aD
java代码: 1<r!9x9G
\f9WpAY
gk%nF
package com.intokr.util; dk|LC-]`A
72dRp!JU
import java.util.List; 7;EDU
@]l|-xGCWn
/** $6rm;UH
* 用于分页的类<br> W%L'nR~w$
* 可以用于传递查询的结果也可以用于传送查询的参数<br> wQ+pVu?6_
* ,1sbY!&ekL
* @version 0.01 yYP_TuNa
* @author cheng "ko*-FrQ
*/ [bhKL5l
public class Paginator<E> { #
e?B
privateint count = 0; // 总记录数 f24W*#IX
privateint p = 1; // 页编号 q/EX`%U
privateint num = 20; // 每页的记录数 ]-\68b N
privateList<E> results = null; // 结果 4z<c8
E8
yB UQ!4e
/** m!FuC=e
* 结果总数 ]Dq6XR
*/ !85bpQ.
publicint getCount(){ d{S'6*`D
return count; /vSGmW-*
} QX=TuyO
g *Js4
publicvoid setCount(int count){ Cbff:IP
this.count = count; EO !,rB7I
} t2dsYU/
KuJ)alD;1
/** }4C_r'd6
* 本结果所在的页码,从1开始 1-y8Hy_a2
* <=.6Z*x+
* @return Returns the pageNo. <2pp6je\0s
*/ \?n6l7*t>
publicint getP(){ ]Y[N=G
return p; *Jsb~wta
} XDPR$u8hM
,Cr%2Wg-
/** &>jz[3
* if(p<=0) p=1 >Sc yc-n
* 0AO^d[v
* @param p /8l-@P.o
*/ ^Q8yb*MN
publicvoid setP(int p){ s5*4<VxQN.
if(p <= 0) `%Ih'(ne
p = 1; 6e ?xu8|
this.p = p; ?|5M'o|9
} 7KIekL
P]Fb0X
/** >=N-P<%
* 每页记录数量 DT]4C!dh
*/ VIF43/>(
publicint getNum(){ U"GxXrl
return num; p<L7qwOii
} wpZ"B+oK!
1M`E.Ztw*
/** $Tbsre\MJ
* if(num<1) num=1 5;)^o3X>
*/ UT3Fi@
publicvoid setNum(int num){ [Mu9"kF
if(num < 1) :rb;*nY!
num = 1; W8& )UtWQ
this.num = num; 01mu6)
} 9k6s
M(C">L]8
/** );!ND%
* 获得总页数 \TP$2i%W
*/ s{^B98d+W
publicint getPageNum(){ tD.#*.7
return(count - 1) / num + 1; zH1;h
} kK75 (x
J1w[gf]J
/** g
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* 获得本页的开始编号,为 (p-1)*num+1 KdoI
*/ ]aPf-O*
publicint getStart(){ do8[wej<:
return(p - 1) * num + 1; /r7xA}se^
} 6_`Bo%
f/Y&)#g>k
/** 3q%z
* @return Returns the results. =`+D/
W\[Y
*/ &{j!!LL
publicList<E> getResults(){ ?M:>2wl
return results; i]Mem M-
} B{/og*xd*1
a"@f< wU~
public void setResults(List<E> results){ Z1fY' f
this.results = results; ()aCE^C
} U`6|K$@
e=&~6bs1U
public String toString(){ ~xqiasE#K
StringBuilder buff = new StringBuilder ~v8X>XDL?T
xL15uWk-
(); ,>B11Z}PH
buff.append("{"); Z
)c\B
buff.append("count:").append(count); Ck/44Wfej
buff.append(",p:").append(p); fTj@/"a
buff.append(",nump:").append(num); gXI-{R7Me
buff.append(",results:").append 'HWl_M
cX9o'e:C
(results); xb\EJ1M>
buff.append("}"); 3wfcGQn|sD
return buff.toString(); HO<|EH~lu
} I(M/X/
336ETrG^0
} =dQ[I6
uGZGI;9f4
xgxfPcI