Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3"e,qY
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 V!=,0zy~Z
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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 '<<t]kK[N
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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
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分页支持类: n\DV3rXI9
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java代码: cq]6XK-W
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package com.javaeye.common.util; ;^*W+,4WB
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import java.util.List; FZlWsp=
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publicclass PaginationSupport { n>YKa)|W`
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publicfinalstaticint PAGESIZE = 30; zF<R'XP
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privateint pageSize = PAGESIZE; ,qxu|9L
*]X'( /b_
privateList items; &QgR*,5eo
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privateint totalCount; 5b*C1HS@X
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privateint[] indexes = newint[0]; yN-9[P8C
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privateint startIndex = 0;
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public PaginationSupport(List items, int ?@86P|19
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totalCount){ Z T%5T}i
setPageSize(PAGESIZE); H:|uw
setTotalCount(totalCount); "y}5;9#,
setItems(items); }K(TjZR
setStartIndex(0); HRA|q
} TLH1>pY&
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public PaginationSupport(List items, int $&c*'3
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totalCount, int startIndex){ tw@X>
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setPageSize(PAGESIZE); PJ#,2=n~
setTotalCount(totalCount); ~n_HP_Kf?
setItems(items); He@KV=
setStartIndex(startIndex); UN#S;x*
} TWTb?HP
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public PaginationSupport(List items, int
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); }GM'.yutX
setTotalCount(totalCount); (ZlU^Gw#UB
setItems(items); ~xTt204S
setStartIndex(startIndex); -9?]IIVb
} ;_=&-mz
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publicList getItems(){ A#,ZUOPGH
return items; ;'1d1\wiDQ
} V7/Rby Q
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publicvoid setItems(List items){ 8ao _i=&x
this.items = items; UiNP3TJ'L
} V;=cwy)I
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publicint getPageSize(){ uxz^/Gk
return pageSize; EU#^7
} %C]>9."
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publicvoid setPageSize(int pageSize){ zH
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this.pageSize = pageSize; Z\sDUJ
} '"s@enD0 y
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publicint getTotalCount(){ v$9y,^p@e
return totalCount; |s_GlJV.
} DmcZta8n]
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publicvoid setTotalCount(int totalCount){ yhJ@(tu.Gd
if(totalCount > 0){ :4|4 =mkr
this.totalCount = totalCount; !)$Zp\Sg
int count = totalCount / ~TtiO#,t
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pageSize; rm_Nn8p,
if(totalCount % pageSize > 0) Hn:Crl y#
count++; 7zc^!LrW<
indexes = newint[count]; ^.y\(=
for(int i = 0; i < count; i++){ iy"*5<;*DD
indexes = pageSize * %iB,IEw
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} O/LXdz0B
}else{ EQ_aa@M7
this.totalCount = 0; Q2>gU#
} 6LhTBV
} 7:@'B|
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publicint[] getIndexes(){ Ys7]B9/1O
return indexes; y{Q
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} I1J-)R+
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publicvoid setIndexes(int[] indexes){ PvL[e"p
this.indexes = indexes; H?w6C):]
} Y/oHu@
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publicint getStartIndex(){ /wv0i3_e
return startIndex; <3
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} VU#7%ufu&
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publicvoid setStartIndex(int startIndex){ pfPz8L.7
if(totalCount <= 0) #&4=VGx{
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this.startIndex = 0; TA\vZGJ('
elseif(startIndex >= totalCount) Gm`8q}<I
this.startIndex = indexes q\ %I#1
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[indexes.length - 1]; {`_i`
elseif(startIndex < 0) +T+#q@
this.startIndex = 0; \. S/|
else{ Rb;'O89Hj@
this.startIndex = indexes F"kAkX>3}
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[startIndex / pageSize]; 3g
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} `0svy}
} /kG_*>.Z
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publicint getNextIndex(){ ->jDb/a{C
int nextIndex = getStartIndex() + p4QU9DF
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pageSize; O0:q;<>z
if(nextIndex >= totalCount) |BYRe1l6l
return getStartIndex(); ykJ>*z
else $Kd>:f=A
return nextIndex; 7$#u
} UZ";a453r
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publicint getPreviousIndex(){ +ai<
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int previousIndex = getStartIndex() - 8,|k ao:
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pageSize; bMBLXk
if(previousIndex < 0) MOC/KNb
return0; YZ7.1`8
else z!\*Y
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return previousIndex; 7Yy ;
} /V By^ L:
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} "jCu6Rj d
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抽象业务类 SWLo|)@[/
java代码: ZC8wA;!z^
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/** kT=8e;K
* Created on 2005-7-12 lx i<F
*/ [ hsds\
package com.javaeye.common.business; 8k79&|
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import java.io.Serializable; 2qp#N%
import java.util.List; P2Y^d#jO
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import org.hibernate.Criteria; `h;[TtIX4
import org.hibernate.HibernateException; h];I{crh
import org.hibernate.Session; 2SLU:=<3
import org.hibernate.criterion.DetachedCriteria; =c7;r]Ol
import org.hibernate.criterion.Projections; [-&Zl(9&
import >dT*rH 3w
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org.springframework.orm.hibernate3.HibernateCallback; }WV:erg`
import `X8F`5&U\f
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org.springframework.orm.hibernate3.support.HibernateDaoS TC"<g
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upport; adw2x pj
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import com.javaeye.common.util.PaginationSupport; %)wjR/o
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public abstract class AbstractManager extends 2pAW9R#UV-
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HibernateDaoSupport { 0IpmRH/
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privateboolean cacheQueries = false; 0$njMnB2l
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privateString queryCacheRegion; v>56~AJ
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publicvoid setCacheQueries(boolean =lC7gS!U
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cacheQueries){ = /8cp
this.cacheQueries = cacheQueries; 3a|\dav%
} m kexc~l
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publicvoid setQueryCacheRegion(String nP$9CA
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queryCacheRegion){ s @C}P
this.queryCacheRegion = =Sv/IXX\di
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queryCacheRegion; ])!*_
} /(LL3cZK
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publicvoid save(finalObject entity){ p#Bi>/C6
getHibernateTemplate().save(entity); Z]ONh
} <}LC~B!
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publicvoid persist(finalObject entity){ #1[u(<AS
getHibernateTemplate().save(entity); rs.)CMk53
} =T_g}pu
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publicvoid update(finalObject entity){ Xeajxcop#
getHibernateTemplate().update(entity); [gB+C84%%
} #b`ke/P
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publicvoid delete(finalObject entity){ *](iS
getHibernateTemplate().delete(entity); 7Ix973^
} ~m |BC*)
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publicObject load(finalClass entity, D]}G.v1
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finalSerializable id){ "]dI1 g_
return getHibernateTemplate().load ]{iQ21`a-
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(entity, id); VE24ToI?W"
} =Uh$&m
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publicObject get(finalClass entity, hQi2U
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finalSerializable id){ 9iq_rd]
return getHibernateTemplate().get Uv.)?YeGh
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(entity, id); OCUr{Nh
} ..qCPlK;
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publicList findAll(finalClass entity){ _LPHPj^Pg
return getHibernateTemplate().find("from J *yg&
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" + entity.getName()); /\Ef%@
} 9UkBwS`
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publicList findByNamedQuery(finalString "#] $r
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namedQuery){ OnK4] S5
return getHibernateTemplate :
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().findByNamedQuery(namedQuery); -%~4W?
} M{\I8oOg
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publicList findByNamedQuery(finalString query, J1vR5wbu
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finalObject parameter){ g*Phv|kI
return getHibernateTemplate '7/)Ot(
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().findByNamedQuery(query, parameter); hc1N~$3!G
} `gJ(0#ac
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publicList findByNamedQuery(finalString query, ?`#Khff?
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finalObject[] parameters){ aYeR{Y]
return getHibernateTemplate JLYi]nZ
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().findByNamedQuery(query, parameters); IcEdG(
} JVJMgim)0
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publicList find(finalString query){ 4JEpl'5^Q
return getHibernateTemplate().find /mHqurB
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(query); ),)lzN%!
} <GJbmRc|
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publicList find(finalString query, finalObject Bwrx *J
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parameter){ ~@!bsLSMU
return getHibernateTemplate().find j+!v}*I![
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(query, parameter); )1z@
} q| 7(
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public PaginationSupport findPageByCriteria ,_P-$lB
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(final DetachedCriteria detachedCriteria){ W/ \g~=vo
return findPageByCriteria No$3"4wk
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \^LFkp
} <$YlH@;)`a
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public PaginationSupport findPageByCriteria u?"Vm
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(final DetachedCriteria detachedCriteria, finalint 6LZCgdS{
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startIndex){ *v`eUQ:
return findPageByCriteria &[9709 (=
}b}m3i1
(detachedCriteria, PaginationSupport.PAGESIZE, jCY%|
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startIndex); {I((p_
} _GPe<H
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public PaginationSupport findPageByCriteria *i,%,O96Nz
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(final DetachedCriteria detachedCriteria, finalint ,+VGSd
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pageSize, SJLis"8
finalint startIndex){ >!JS:5|
return(PaginationSupport) TvM~y\s
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getHibernateTemplate().execute(new HibernateCallback(){ [Pp'Ye~K@c
publicObject doInHibernate ^Pf WG*
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(Session session)throws HibernateException { AX INThJ
Criteria criteria = ]|@^1we
l] vm=7:
detachedCriteria.getExecutableCriteria(session); _aphkeqd
int totalCount = xk5]^yDp
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((Integer) criteria.setProjection(Projections.rowCount YUb_y^B^
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()).uniqueResult()).intValue(); *a)n62
criteria.setProjection mv><HqDL1
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]
(null); #mT"gs
List items = 5-V pJ
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criteria.setFirstResult(startIndex).setMaxResults $qiya[&G4
"Q<MS'a
(pageSize).list(); #tHK"20
PaginationSupport ps = cL ]1f
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new PaginationSupport(items, totalCount, pageSize, SM'|+ d
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startIndex); do_[&
return ps; NbobliC=
} |)&%A%m
}, true); GyIV
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} #cJ@uqR
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public List findAllByCriteria(final .`lCWeHN
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DetachedCriteria detachedCriteria){ gi8FHSU|G
return(List) getHibernateTemplate wY#E?,
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().execute(new HibernateCallback(){ ?[AD=rUC
publicObject doInHibernate c$,P ~Ws'
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(Session session)throws HibernateException { Dv"9qk
Criteria criteria = sK{e*[I>W
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detachedCriteria.getExecutableCriteria(session); 'F<TSy|4kI
return criteria.list(); sB</DS
} XSDpRo
}, true); '%qr.T
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} CAJ'zA|o
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public int getCountByCriteria(final yevPHN"M
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DetachedCriteria detachedCriteria){ yfSmDPh
Integer count = (Integer) hM{bavd
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getHibernateTemplate().execute(new HibernateCallback(){ +TJCLZ..
publicObject doInHibernate M{@(G5
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(Session session)throws HibernateException { UZMd~|
Criteria criteria = uD'6mk*
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detachedCriteria.getExecutableCriteria(session); Ey2^?
return Sf'CN8
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criteria.setProjection(Projections.rowCount zdYjF|
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()).uniqueResult(); DF= *_,2/
} CY1Z'
}, true); .3;;;K9a~]
return count.intValue(); s#11FfF`
} o4X{L`m
} Wc#24:OKe3
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用户在web层构造查询条件detachedCriteria,和可选的 UVP vOtZj
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 29KiuP
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PaginationSupport的实例ps。 3n _htgcv
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ps.getItems()得到已分页好的结果集 {.yB'.k?
ps.getIndexes()得到分页索引的数组 {mg2pfhB!
ps.getTotalCount()得到总结果数 M >u_4AY
ps.getStartIndex()当前分页索引 QV!up^Zso
ps.getNextIndex()下一页索引 2ESo2
ps.getPreviousIndex()上一页索引 ]DcFySyv
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 t_^4`dW`
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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 )e{aN+
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一下代码重构了。 5O%{{J
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我把原本我的做法也提供出来供大家讨论吧: I,tud!p`
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首先,为了实现分页查询,我封装了一个Page类: ^W^OfY
java代码: @dKTx#gZ
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/*Created on 2005-4-14*/ m`XHKRp
package org.flyware.util.page; 3BI1fXT4=j
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/** R_C)
* @author Joa R&&4y 7
* A^g(k5M*
*/ dN q$}
publicclass Page { h{Y",7]!
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/** imply if the page has previous page */ gdc<ZYcM
privateboolean hasPrePage; 7#Ft|5$~q
tw;}jh
/** imply if the page has next page */ b}`TLn
privateboolean hasNextPage; [JiH\+XLPs
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/** the number of every page */ -RwE%cr
privateint everyPage; fC`&g~yK'
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/** the total page number */ ?}oFg#m-<L
privateint totalPage; `?]k{ l1R
9{l}bu/u
/** the number of current page */ dPlV>IM$z
privateint currentPage; T)/eeZ$
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/** the begin index of the records by the current P:c w|Q
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query */ 54T`OE
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privateint beginIndex; /m1\ iM\
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/** The default constructor */ HPl<%%TI
public Page(){ pBHRa?Y5
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} SUiOJ[5,
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/** construct the page by everyPage j#|ZP-=1_
* @param everyPage vh^VxS
* */ q9"96({\@
public Page(int everyPage){ i1UsIT
this.everyPage = everyPage; e'~3oqSvR
} Q,g\
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/** The whole constructor */ ?uu*L6
public Page(boolean hasPrePage, boolean hasNextPage, aE8VZ8tvq
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int everyPage, int totalPage, * 4'"2"
int currentPage, int beginIndex){ {7[Ox<Ho
this.hasPrePage = hasPrePage; Jy)/%p~
this.hasNextPage = hasNextPage; O.? JmE
this.everyPage = everyPage; Gc?a +T
this.totalPage = totalPage; /~1+i'7V.,
this.currentPage = currentPage; MgZ/(X E
this.beginIndex = beginIndex; 4#D,?eA7
} Mx}gN:Wt
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/** &>O+}>lr9
* @return \bXa&Lq
* Returns the beginIndex. =;L|gtH"
*/ UQsN'r\tS
publicint getBeginIndex(){ \z$= K
return beginIndex; j 7B!h|
} )%TmAaj9d
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/** 8*X4\3:*N
* @param beginIndex &=[WIG+rk
* The beginIndex to set. >*bvw~y,
*/ ".%k6W<n
publicvoid setBeginIndex(int beginIndex){ k$Vl fQ'+
this.beginIndex = beginIndex; ]Ljf?tk
} mFeP9MfJ
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/** '/p4O2b,
* @return ?6!LL5a.
* Returns the currentPage. P}iE+Z3
*/ +`4A$#$+y
publicint getCurrentPage(){ T{"(\X$
return currentPage; 6]N.%Y[(
} bA 2pbjg=
@ Qe0! (_=
/** Z+SRXKQ
* @param currentPage 9c],<;{'
* The currentPage to set. 637:
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*/ ceA9){
publicvoid setCurrentPage(int currentPage){ }V>T M{
this.currentPage = currentPage; Om&Dw|xG8
} f);FoVa6
MV"=19]
/** #yen8SskB
* @return 4-w{BZuS
* Returns the everyPage. UiWg<_<t
*/ =4!mAo}
publicint getEveryPage(){ $G>. \t
return everyPage; ]:;&1h3'7
} iU-j"&L5
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/** ]9-\~Mwh
* @param everyPage 2oW"'43X
* The everyPage to set. XW9!p.*.U
*/ ,4rPg]r@
publicvoid setEveryPage(int everyPage){ }Jw,>}
this.everyPage = everyPage; ]n~V!hl?A
} a*;b^Ze`v
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/** /reX{Y
* @return iso4]>LF
* Returns the hasNextPage. @HW*09TG
*/ Efe 7gE'
publicboolean getHasNextPage(){ & kIFcd@
return hasNextPage; iLT}oKF2N;
} 9mgIUjz
^Cmyx3O^
/** E7hhew
* @param hasNextPage rNM;ZPF#
* The hasNextPage to set. ?%86/N>
*/ w!CNRtM:~
publicvoid setHasNextPage(boolean hasNextPage){ 6zkaOA46V
this.hasNextPage = hasNextPage; B!yr!DWv
} dx]>(e@(t{
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/** <i[HbgUlO.
* @return q4q6c")zp
* Returns the hasPrePage. ex|F|0k4}
*/ ijcm2FJcG
publicboolean getHasPrePage(){ N [@?gFtT
return hasPrePage; Vi}_{
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} g`^x@rj`E
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/** IID5c"
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* @param hasPrePage l2d{ 73h
* The hasPrePage to set. 4 :=]<sc,
*/ a?.=V
publicvoid setHasPrePage(boolean hasPrePage){ @;kSx":b
this.hasPrePage = hasPrePage; |}1dFp
} hph4 `{T
h![#;>(
/** f?b"i A(6
* @return Returns the totalPage. P2!C|SLK
* zX~MC?,W1
*/ l,:F
publicint getTotalPage(){ Q&&@v4L
return totalPage; m*;ERK
} v:p} B$
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/** Fi1@MG5$2
* @param totalPage zL it
* The totalPage to set. P4?glh q#
*/ mq[ug>
publicvoid setTotalPage(int totalPage){ BHw, 4#F1;
this.totalPage = totalPage; *H122njH+T
} F/Pep?'
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} #%s#c0TX
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 7KPwQ?SjT
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个PageUtil,负责对Page对象进行构造: F"<vaqT2
java代码: Ah<+y\C
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/*Created on 2005-4-14*/ 6#yUc_5 \
package org.flyware.util.page; j4b4!^fV
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import org.apache.commons.logging.Log;
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import org.apache.commons.logging.LogFactory; IAEAhqp
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/** 2(nlJ7R
* @author Joa fLVAKn
* ^GX)Z~
*/ DN/YHSYK
publicclass PageUtil { a>)f=uS
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privatestaticfinal Log logger = LogFactory.getLog W`&hp6Jq
\f)#>+X-
(PageUtil.class); e*!kZAf
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/** 3[&C g
* Use the origin page to create a new page .G^YqJ 4
* @param page h1{3njdr
* @param totalRecords ~v83pu1!2s
* @return 5?L<N:;J_
*/ KU;9}!#
publicstatic Page createPage(Page page, int Q &t<Y^B
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totalRecords){ _rYkis^u
return createPage(page.getEveryPage(), |%v^W 3
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page.getCurrentPage(), totalRecords); mqJ_W[y7
} !-Y3V"
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/** %bfZn9_m
* the basic page utils not including exception 'n|5ZhXPB
6^Sa;
handler XlJZhc
* @param everyPage \?N2=jsu$
* @param currentPage - YV>j
* @param totalRecords Tf)*4O4@'
* @return page fAmz4
*/ y==CTY@
publicstatic Page createPage(int everyPage, int $SE^S
1.X@;
currentPage, int totalRecords){ pNIf=lA
everyPage = getEveryPage(everyPage); y?:.;%!E
currentPage = getCurrentPage(currentPage); xm@_IL&P
int beginIndex = getBeginIndex(everyPage, qFNes)_r
2
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currentPage); Z/K{A`
int totalPage = getTotalPage(everyPage, sC ;+F*0g
?s _5&j7
totalRecords); ASfaX:ke
boolean hasNextPage = hasNextPage(currentPage, 6&-(&(_
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totalPage); Z)\@i=m
boolean hasPrePage = hasPrePage(currentPage); 7)k\{&+P
km40qO@3
returnnew Page(hasPrePage, hasNextPage, ?
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everyPage, totalPage, r9lR|\Ax2U
currentPage, ]q-Y }1di8
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beginIndex); ~,~eoW7
} 0LKRN|@
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privatestaticint getEveryPage(int everyPage){ ;\l,5EG
return everyPage == 0 ? 10 : everyPage; {_Gs*<.
} ZW}_Qs
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privatestaticint getCurrentPage(int currentPage){ +]50D xflA
return currentPage == 0 ? 1 : currentPage; Yuc> fFA
} :h V7>
rr
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privatestaticint getBeginIndex(int everyPage, int |W\(kb+
"T"h)L<
currentPage){ ##o#eZq:"
return(currentPage - 1) * everyPage; ow#1="G,=
} 42{:G8
; Hd7*`$
privatestaticint getTotalPage(int everyPage, int ,1##p77.
N"1B/u
totalRecords){ +@:x!q|^
int totalPage = 0; ym6K!i]q4
ujucZ9}yd
if(totalRecords % everyPage == 0) @<Yy{~L|
totalPage = totalRecords / everyPage; !L8#@BjU
else $pudoAO
totalPage = totalRecords / everyPage + 1 ; }{<
'8J.R
So
5N5,u@=
return totalPage; 9$m|'$p3sG
} z"4~P3>{g
BX^tR1
privatestaticboolean hasPrePage(int currentPage){ XGMiW0j0B
return currentPage == 1 ? false : true; IkXx# )
} s!e3|pGS
Ib0ZjX6
privatestaticboolean hasNextPage(int currentPage, nJLFfXWx
8Bg;Kh6B
int totalPage){ \r>6`-cs]
return currentPage == totalPage || totalPage == k: ;WtBC6j
jZ3fKyp#
0 ? false : true; 0P(!j_2m
} 1>&]R=
O,A{3DAe0
~3S~\0&|
} -B\HI*u
zkdetrR
:#~j:C|
++#5
{GcO3G#FZ
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。 ,i@:5X/t
Z87|Zl
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 WSY}d
Vr
PAOJ\U
做法如下: SC])?h-Fw
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 9!DQ~k%
H]jhAf<h
的信息,和一个结果集List: vFK<J Sk!
java代码: j9OG\m
@jlw_ob2g
bNoW?8bZ
/*Created on 2005-6-13*/ z%LIX^q9
package com.adt.bo; HgkC~'
E`k@{*Hn&
import java.util.List; qWKAM@
]P2"[y
import org.flyware.util.page.Page; $"&{aa
BFJnV.0M!
/** [R7Y}k:9U
* @author Joa s&!a
*/ '-/xyAzS
publicclass Result { -8rjgB~."/
aCLq k'
private Page page; KFkoS0M5|
XNu^`Ha
private List content; f:.I0 ST
X/M4!L}\
/** _OC<[A
* The default constructor *GN#
r11d
*/ Clb@$,
public Result(){ 5RpjN: 3
super(); 3gj+%%!G\
} ;?g6QIN9
^B2
-)
/** ?_"ik[w}
* The constructor using fields *%t^;&x?
* M>8A\;"
* @param page %\Mo-Ow!\
* @param content h@]XBv
*/ Bv%GJ*>>
public Result(Page page, List content){ l/
;
this.page = page; "4,?uPi
this.content = content; ">jj
}
{ Z5nGG
'W,jMju
/** 1&(V
* @return Returns the content. ;x1PS
*/ ; XN{x
publicList getContent(){ ([LSsZ]sj
return content; M b1sF
} WPG(@zD
M*HnM(
/** f\>M'{cV
* @return Returns the page. @Sbe^x
*/ Hi`//y*92H
public Page getPage(){ @)&=%
return page; n%s]30Xs
} PJrtMAcKq
xDoC(
/** JOLaP@IPT
* @param content cFnDmtI:
* The content to set. l.bYE/F0&
*/ pWsDzb6?%
public void setContent(List content){ fG(SNNl+D
this.content = content; TNh1hhJ$b
} P{+T<bk|
8j\cL'
/** \:ak ''
* @param page |(LZ9I
* The page to set. dg"3rs /?A
*/ zEy N)
publicvoid setPage(Page page){ 8j %Tf;
this.page = page; o/Q;f@
} !pdb'*,n
} O[)kboY
5m(^W[u `
Q &K
JU5C}%Q6
b4ONh%
2. 编写业务逻辑接口,并实现它(UserManager, A_5P/ARmI
0h\smqm
UserManagerImpl) |3[Wa^U5
java代码: I \[_9
|! E)GahM
:'l^kSP_*C
/*Created on 2005-7-15*/ thM4vq
package com.adt.service; D"?fn<2
364`IC( a
import net.sf.hibernate.HibernateException; 9g"2^^wD
i||]V*5n
import org.flyware.util.page.Page; wN-d'-z/rd
scou%K
import com.adt.bo.Result; `Kr,>sEAM
;^%4Q"
/** QKN+>X
* @author Joa &3Szje
*/ nd1+"-,q
publicinterface UserManager { cH?B[S;]
1\>^m
public Result listUser(Page page)throws Ix=}+K/
Vq?p|wy
HibernateException; ,+xB$e
>X4u]>X
} F!Q@u
jQ
&Ao+X=qw
u5: q$P
/qGf 1MHD
java代码: \2"I;
JYd 'Jp8bP
q~ZNd3O
/*Created on 2005-7-15*/ 78# v
package com.adt.service.impl; R$TB1w9]
K&70{r
import java.util.List; k!HK 97qA
)ZqTwEr@[
import net.sf.hibernate.HibernateException; -pGE]nwDL
Y>G@0r BG
import org.flyware.util.page.Page; ,TN
2
import org.flyware.util.page.PageUtil; kZZh"#W: L
cm[&?
import com.adt.bo.Result; Dq5j1m.
import com.adt.dao.UserDAO; ve/<=IR
Zo
import com.adt.exception.ObjectNotFoundException; IS
2^g>T#1
import com.adt.service.UserManager; e`TH91@
,\ k(x>oy
/** r)~ T@'y
* @author Joa Vq\`+&A
*/ S` ;?z
publicclass UserManagerImpl implements UserManager { X/2&!O
}O^zl#
private UserDAO userDAO; F,MO@&ue"
^T$|J;I
/** ahOM CZF|
* @param userDAO The userDAO to set. ,Pjew%
*/ *q".-u!D[
publicvoid setUserDAO(UserDAO userDAO){ <|+Ex
this.userDAO = userDAO; 27"%"P.1
} 0#&5.Gr)
B$!)YD;
/* (non-Javadoc) V'T ,4
* @see com.adt.service.UserManager#listUser 7=WT69,&
-}=%/|\FG
(org.flyware.util.page.Page) ,:H\E|XeBw
*/ FUOI3
public Result listUser(Page page)throws b6F4>@gjg
^1aAjYFn
HibernateException, ObjectNotFoundException { T'&I{L33Y
int totalRecords = userDAO.getUserCount(); @zz1hU
if(totalRecords == 0) r1LViK
throw new ObjectNotFoundException fhp<oe>D
qI<mjB{3`
("userNotExist"); M|qteo
page = PageUtil.createPage(page, totalRecords); Z2='o_c
List users = userDAO.getUserByPage(page); O0No'LVu
returnnew Result(page, users); xp72>*_9&
} kg3EY<4i
U,q\emR
} 7C ,UDp|
.wu
xoq
M:3h e
}36QsH8
;u(<h?%e
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ;)e2@'Agl
D-(w_$#
询,接下来编写UserDAO的代码: 3G~@H>j
3. UserDAO 和 UserDAOImpl: Z1Z1@2 T
java代码: (%xwl
Mo @C9Y0
K7W6ZH9;
/*Created on 2005-7-15*/ `~;rblo;
package com.adt.dao; @reeO=
C@W"yYt
import java.util.List; ,o,I5>`
ICkp$u^
import org.flyware.util.page.Page; 0B@Jity#!
Qj6/[mUr~
import net.sf.hibernate.HibernateException; R>"OXFaE
)5U[o0td
/** Kt|1&Gk
* @author Joa /_Z652@
*/ r*_ZJ*h[
publicinterface UserDAO extends BaseDAO { ux3<l +jv^
wG<(F}VX
publicList getUserByName(String name)throws .0O2Qqdg
3*)ig@e6
HibernateException;
S"$m]
I{:(z3
publicint getUserCount()throws HibernateException; q]N:Tpm9
D{4YxR
PX
publicList getUserByPage(Page page)throws [$"n^5_~
pV,P|>YTf
HibernateException; GJp85B!PlO
qfz 8jY]
} xD[Gq%
/iV}HV0
<xC#@OZ
z;wELz1L{
e=;AfK
java代码: %v7[[U{T
Zg`Mz
_?
S"k*6U
/*Created on 2005-7-15*/ 'hv k
package com.adt.dao.impl; qt^T6+faaQ
ZMLg;-T.&4
import java.util.List; 5-0{+R5v
jSuL5|Gui
import org.flyware.util.page.Page; 1,~SS
%ck]S!}6
import net.sf.hibernate.HibernateException; 70mpSD3
import net.sf.hibernate.Query; Cp]"1%M,
adi[-L#
import com.adt.dao.UserDAO; 9>rPe1iv
%T9 sz4V
/** DHT&,=
* @author Joa TdGnf
*/ BQ2wnGc
public class UserDAOImpl extends BaseDAOHibernateImpl BC;:
,b;{emX h
implements UserDAO { tP%{P"g3^
-cm$[,b6
/* (non-Javadoc) j"@93D~
* @see com.adt.dao.UserDAO#getUserByName *[R
eb%
j>/ ,$H
(java.lang.String) U Gpu\TB
*/ ;6{@^
publicList getUserByName(String name)throws N**g]T
0`
ee#):
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HibernateException { fb:j%1WF
String querySentence = "FROM user in class /q$,'^.A
IMl!,(6;
com.adt.po.User WHERE user.name=:name"; ^~HQC*
Query query = getSession().createQuery ?EK?b
s
~ Yngkt
(querySentence); 13&0rLS
query.setParameter("name", name); .eO?Z^
return query.list(); h"[+)q%L
} dN}#2Bo=
Uyr3dN%*r
/* (non-Javadoc) k8uvNLA)a
* @see com.adt.dao.UserDAO#getUserCount() {E0z@D)U-
*/ 5pRV3K{H
publicint getUserCount()throws HibernateException { j]m|7]
int count = 0; ed_FiQd
String querySentence = "SELECT count(*) FROM zb
Z4|_
'vaLUy9]
user in class com.adt.po.User"; .pvV1JA'
Query query = getSession().createQuery RTu4@7XP
Wt9Q;hK
(querySentence); T}=>C+3r
count = ((Integer)query.iterate().next awUx=%ERtA
4~OQhiJ
()).intValue(); R?EASc!b
return count; }AvcoD/b
} nbTVU+
HH>:g(bu
/* (non-Javadoc) fn/7wO$!
* @see com.adt.dao.UserDAO#getUserByPage ^+9sG$T_EV
`H3.,]
(org.flyware.util.page.Page) `3'0I /d"z
*/ ~b|`'kU
publicList getUserByPage(Page page)throws ]}6w#)]"
08m;{+|vY
HibernateException { C}*cx$.
String querySentence = "FROM user in class ^Mk%z9
?
cbu@*NzY,
com.adt.po.User"; \rV
B5|D?
Query query = getSession().createQuery D*Q.G8(
5I@w~z
(querySentence); lw(e3j
query.setFirstResult(page.getBeginIndex()) U70]!EaT
.setMaxResults(page.getEveryPage()); PSmfiaThwo
return query.list(); 0G2g4DSKD
} Zf>^4_x3P
KYxBVgJ
} @i3bgx>_o
9r2IuS0
io3yLIy,
*+b6B_u]
<p?&udqD
至此,一个完整的分页程序完成。前台的只需要调用 WWZ9._
f0LP?]
userManager.listUser(page)即可得到一个Page对象和结果集对象 y9|K|xO[
<d7V<&@o=
的综合体,而传入的参数page对象则可以由前台传入,如果用 *AIEl"29
!"TZ:"VZU
webwork,甚至可以直接在配置文件中指定。 -gz0md|Y
fXQiNm[P
下面给出一个webwork调用示例: ;*[9Q'lI*
java代码: S?0)1O
:b,^J&~/)1
N|2y"5
/*Created on 2005-6-17*/ Y3ZK%OyPR
package com.adt.action.user; J%]D%2vnk`
^5 t
import java.util.List; Ut)r&?
2_t=P|Uo
import org.apache.commons.logging.Log; 9(!]NNf!
import org.apache.commons.logging.LogFactory; cDXsi#Raj
import org.flyware.util.page.Page; O8N[Jl
jRpdft
import com.adt.bo.Result; 2~;&g?T6
import com.adt.service.UserService; 0%;146.p
import com.opensymphony.xwork.Action; ^aRgMuU
~ekh1^evu
/** vY*\R0/a
* @author Joa Yp4c'Zk
*/ '7im
publicclass ListUser implementsAction{ dy>|cj
n!He&
privatestaticfinal Log logger = LogFactory.getLog sxED7,A
0D(cXzQP
(ListUser.class); R& =f:sEi
8"vwU@cfC
private UserService userService; >LF&EM]
!
qJI'+_
private Page page; e^$j5jV
H%z@h~s>
privateList users; .#5l$['
&}`K^5K|O:
/* aP>37s
* (non-Javadoc) 1{2eY%+C
* !|m9|
* @see com.opensymphony.xwork.Action#execute() ! ]Mc4!E
*/ S C_|A9
publicString execute()throwsException{ yD)"c.
Result result = userService.listUser(page); " B@jfa%
page = result.getPage(); pyW u9
users = result.getContent(); =<<3Pkv7@
return SUCCESS; e"+dTq8W
} hQgN9S5P
S9Yt 1qb
/** 3#<*k>1G?
* @return Returns the page. $~'Tf>e
*/ ?Cci:Lin
public Page getPage(){ O(OmGu4%
return page; n!N\zx8
} (3EUy"z-
M'1HA
/** XSB8z
* @return Returns the users. Z-|li}lDr
*/ iG[?
]]
publicList getUsers(){ Ds5NAp:x
return users; ^@}#me@
} Ud3""C5B
N5q725zJ
/** ZcZ;$*
* @param page j.QHkI1.
* The page to set. z*.v_Mx
*/ "jZm0U$,*
publicvoid setPage(Page page){ Qm);6X
this.page = page; C;sgK
} YlUpASW
S]yvMj_?
/** #Mi|IwL
* @param users ^&:'NR
* The users to set. O2H/rFx4
*/ c)1=U_6 1
publicvoid setUsers(List users){ wR7aQg
this.users = users; c d%hW
} _@ i>s,
AQci,j"
/** $ly0h W
* @param userService }~*rx7p
* The userService to set. lvufk VG|
*/ XN;/nU
publicvoid setUserService(UserService userService){ pVOI5>f\
this.userService = userService; ?*K<*wBw#
} v'nHFC+p
} i f@W
]%
Jqg3.2q
aW@oE
~`
PqhlXqX9
VBx,iuaw
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 8t9aHla
&`PbO
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 j+1KNH
>}F? <JB
么只需要: DM2Q1Dh3
java代码: YZ[%uArm
&"j@79Ym1~
!P" ?
<?xml version="1.0"?> Gj`f--2GE
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Ve14rn
%vc'{`P
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 4!2SS
slSR=XOG
1.0.dtd"> R ]=SWE}U
]7F)bIG[
<xwork> ZW* fOaj
lS3 _Ild
<package name="user" extends="webwork- )@c3##Zp)
NS5 49S
interceptors"> H^v{Vo
n^6TP'r
<!-- The default interceptor stack name f%1wMOzx
/'+4vXc@
--> 0=,'{Vz}A
<default-interceptor-ref &enlAV'#)O
s=\7)n=,M
name="myDefaultWebStack"/> *eoq=,O
mCrU//G
<action name="listUser" {Pvr??"r
Isp_U5M
class="com.adt.action.user.ListUser"> 3YRBI|XO
<param ;@'0T4Z&l
dMgbW<uAu
name="page.everyPage">10</param> WH;xq^
<result sbjtL,
`]LODgk~
name="success">/user/user_list.jsp</result> 5@.zz"o.`
</action> | /#'S&!U
;q&Z9lm
</package> [EOMCH2Ki
w}b<D#0XC
</xwork> GFY-IC+fc
'Ix5,^M}B
g$gVm:=
V*kznm
d'q;+jnP
R]VTV7D
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 |3|wdzV
7rPLnB]
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。 PoY>5
@d
P~X
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Wb'*lT0=
1YFAr}M
x/[8Wi,yB
K5+!(5V~
%)dI2 J^Xf
我写的一个用于分页的类,用了泛型了,hoho :3 PG f
7ozYq_ $
java代码: TwwIt5_fN
1+FYjh!2t
T*p|'Q`
package com.intokr.util; _dY:)%[]
o8mo=V4j
import java.util.List; $;ch82UiX
4&H+hN{3
/** kEx8+2s=M
* 用于分页的类<br> gBfX}EK7F
* 可以用于传递查询的结果也可以用于传送查询的参数<br> }P16Xb)p
* % M+s{ l
* @version 0.01 pV_}Or_
* @author cheng \4C)~T:*
*/ zAu}hVcW
public class Paginator<E> {
Ckw83X
privateint count = 0; // 总记录数 S{Rh'x\B
privateint p = 1; // 页编号 H.)fOctbO
privateint num = 20; // 每页的记录数 IS .g);Gj
privateList<E> results = null; // 结果 t0+t9w/fTP
@],Z 2
/** `2sdZ/fO
* 结果总数 .k
p$oAL
*/ ^]KIgGv\
publicint getCount(){ V_ {vZ/0e
return count; M44_us
} ?TRW"%
E]1\iV
publicvoid setCount(int count){ $To4dJb
this.count = count; =tLU]
} %{=4Fa(Jux
|F3vRt@
/** EmYO5Whi
* 本结果所在的页码,从1开始 _dz+2au
* [p2g_bI8yK
* @return Returns the pageNo. Q1K"%
*/ B<rPvM7a
publicint getP(){ rrW! X q
return p; !Jh*a *I}
} BllDWKb
<r@bNx@T
/** R
A*(|n>
* if(p<=0) p=1 (di)`D5Q
* OE5 X8DqQe
* @param p d5N)^\z
*/ ;&/sj-xJ2
publicvoid setP(int p){ [))gn
if(p <= 0) aS3P(s L
p = 1; :17ee
this.p = p; $0ym_6n
} BYTXAZLb
:t_}_!~
/** ;D6x=v=2
* 每页记录数量 @2QJm
*/ y-D>xV)n
publicint getNum(){ L;
@aE[#z
return num; _a?wf!4>P
} e-&L\M
JkRGt Yq
/** 9)8*FahW
* if(num<1) num=1 hB?U5J
*/ wn&[1gBxM
publicvoid setNum(int num){ DX]z=d)tc
if(num < 1) 4da^d9ZOy
num = 1; cYBrRTrI#
this.num = num; bkJwP s
} hhN(;.
P?-d[zLA
/** tsCz+MP
* 获得总页数 ^xBb$
*/ F Bd+=bx,Z
publicint getPageNum(){ FjK Ke7
return(count - 1) / num + 1; =M Q2sb
} O e0KAn
OJh+[bf"
/** w@<<zItSo
* 获得本页的开始编号,为 (p-1)*num+1 {"qW~S90YO
*/ V3aY]#Su
publicint getStart(){ >b[4
return(p - 1) * num + 1; !pE>O-| K
} q8&4=eV\A
H620vlC}V
/** |DdW<IT`0
* @return Returns the results. .&aVx]
*/ UHTb61Gs
publicList<E> getResults(){ ~hxeD" w
return results;
Y-
z~#;
} .H*? '*
4nX'a*'D~}
public void setResults(List<E> results){ Vs2 v j
this.results = results; /v<e$0~s<
} N^nDWK
d!a2[2Us
public String toString(){ BxW||O|_N"
StringBuilder buff = new StringBuilder =|DkD-
O
$i5G7b
(); s.k`];wo
buff.append("{"); S^_JC
buff.append("count:").append(count); x`j_d:C~G
buff.append(",p:").append(p); AmUe0CQ:k'
buff.append(",nump:").append(num); K6PC&+x
buff.append(",results:").append ^MF=,U'8
bCe[nmE2
(results); oW\Q>c7
=
buff.append("}"); rzc 3k~@
return buff.toString(); #,Fx@3y\a
} _.s\qQ
72BzvY.
} +4p2KYO
b*$o[wO9
.pNq-T