Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 d0Qd$ .%A
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根
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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 {~sDYRX
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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 SY^t} A7:/
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分页支持类: g/+C@_&m
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java代码: OFv%B/O
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package com.javaeye.common.util; 48qV>Gwf
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import java.util.List; #( jw!d&
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publicclass PaginationSupport { E}p&2P+MR
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publicfinalstaticint PAGESIZE = 30; 2h1C9n%j9
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privateint pageSize = PAGESIZE; U\;6mK)M^J
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privateList items; ^,8)iV0j_
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privateint totalCount; L=8<B=QT$
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privateint[] indexes = newint[0]; 27"%"P.1
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privateint startIndex = 0;
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public PaginationSupport(List items, int 7=WT69,&
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totalCount){ `[)YEgs
setPageSize(PAGESIZE); %i-c0|,T4
setTotalCount(totalCount); _m'Fr
7
setItems(items); r{ef .^&:
setStartIndex(0); ~ZhraSI)G
} hKjt'N:~ZY
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public PaginationSupport(List items, int "a"]o
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totalCount, int startIndex){ 'BPp ]R#{
setPageSize(PAGESIZE); 7MHKeLq
setTotalCount(totalCount); &LVn6zAba
setItems(items); Nkl_Ho,
setStartIndex(startIndex); k
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} 7C ,UDp|
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public PaginationSupport(List items, int }36QsH8
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totalCount, int pageSize, int startIndex){ >U*T0FL7
setPageSize(pageSize); D'A/wG
setTotalCount(totalCount); @8^[!F
setItems(items); Mt5PaTjj
setStartIndex(startIndex); *"n vX2iz
} okv 1K
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publicList getItems(){ Dzs[GAQ]
return items; YY!6/5*/]
} \y)
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publicvoid setItems(List items){ ";Rtiiu
this.items = items; $8[r9L!
} }S$@ Ez6
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publicint getPageSize(){ x{c/$+Z[
return pageSize; <l9-;2L4
} !\L/[:n
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publicvoid setPageSize(int pageSize){ ugx%_x6
this.pageSize = pageSize; fUQ6Z,9
} ?Poq2
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publicint getTotalCount(){ Ve!fU
return totalCount; !M]\I &
} sZm$|T0
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publicvoid setTotalCount(int totalCount){ i?e`:}T
if(totalCount > 0){ $Gv9m
this.totalCount = totalCount; /BV03B
int count = totalCount / x61 U[/r
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pageSize; z0*_^MH
if(totalCount % pageSize > 0) }HYjA4o\A
count++; jR#~I@q^
indexes = newint[count]; _({A\}Q|
for(int i = 0; i < count; i++){ mJ`A_0
indexes = pageSize * {aJJ`t
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i; @wC5 g 4E
} i'wAE:Xe
}else{ g9WGkHF
this.totalCount = 0; |{ PI102
} ['*8IWg
} w{90`
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publicint[] getIndexes(){ g
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return indexes; 6]pX>Xho
} Y.U[wL>
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publicvoid setIndexes(int[] indexes){ {Gw.l."
this.indexes = indexes; @%lBrM
} zyg
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publicint getStartIndex(){ z)=+ F]
return startIndex; XNb ZNaAd
} F.=Bnw/-
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publicvoid setStartIndex(int startIndex){ SdwS= (e6
if(totalCount <= 0) %8M)2?E
this.startIndex = 0; Io|Aj
elseif(startIndex >= totalCount) 0{PzUIM,W
this.startIndex = indexes n[,w f9
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[indexes.length - 1]; _fP&&}
elseif(startIndex < 0) R$Tp8G>j
this.startIndex = 0; { F}; n?'
else{ 8Bq!4uq\5|
this.startIndex = indexes .rJiyED?!
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[startIndex / pageSize]; &0 BdUU+:<
} f5==";eP
} (V% `k'N7f
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publicint getNextIndex(){ pdEiqLhH
int nextIndex = getStartIndex() + _ _>.,gL7
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pageSize; gOK\%&S]
if(nextIndex >= totalCount) [e4]"v`N
return getStartIndex(); ?
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else ~w;]c_{.b
return nextIndex; ~E^,=4
} D\YE^8/
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publicint getPreviousIndex(){ vuFBET,
int previousIndex = getStartIndex() - |s)?cpb
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pageSize; K[7EOXLy
if(previousIndex < 0) e<#DdpX!H~
return0; nbTVU+
else HH>:g(bu
return previousIndex; fn/7wO$!
} *79m^
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} o!r8{L
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抽象业务类 `g1iCF
java代码: Y05P'Q
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/** ,xT?mt}P
* Created on 2005-7-12 e%>b+Sv
*/ A[YpcG'9
package com.javaeye.common.business; O!Z|r?
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import java.io.Serializable; a3>zoN
import java.util.List; GBC*>Y
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import org.hibernate.Criteria; Q9`QL3LQD
import org.hibernate.HibernateException; a%Jx
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import org.hibernate.Session; 5Y3i|cj
import org.hibernate.criterion.DetachedCriteria; -sMyt HH.
import org.hibernate.criterion.Projections; tB'V
import f0LP?]
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org.springframework.orm.hibernate3.HibernateCallback; S-nlr@w8
import :9|W#d{o
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org.springframework.orm.hibernate3.support.HibernateDaoS ro[Y-o5Q0
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upport; -n? g~(/P
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import com.javaeye.common.util.PaginationSupport; OW(&s,|6x
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public abstract class AbstractManager extends Zzl,gy70
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HibernateDaoSupport { :;!\vfZbU
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privateboolean cacheQueries = false; ;bX4(CMe
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privateString queryCacheRegion; oAZh~~tp
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publicvoid setCacheQueries(boolean VRW]a
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cacheQueries){ HZ*0QgW\(5
this.cacheQueries = cacheQueries; vG2b:[W
} <39!G7ny
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publicvoid setQueryCacheRegion(String (HN4g;{
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queryCacheRegion){ p'{xoV
this.queryCacheRegion = })IO#,
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queryCacheRegion; "MiD8wX-
} p&K\]l}
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publicvoid save(finalObject entity){ !1uzX
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getHibernateTemplate().save(entity); Gr(|Ra.
} 3|Y!2b(:?
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publicvoid persist(finalObject entity){ e^$j5jV
getHibernateTemplate().save(entity); H%z@h~s>
} .#5l$['
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publicvoid update(finalObject entity){ $'[q4 wo<
getHibernateTemplate().update(entity); \`xkp[C
} *,\` o~
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publicvoid delete(finalObject entity){ }+Vv0jX|V
getHibernateTemplate().delete(entity); 8Vt4HD 08
} qSO*$1i
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publicObject load(finalClass entity, ad`_>lA4Lp
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finalSerializable id){ 8Xm@r#Oy5
return getHibernateTemplate().load u=qPzmywt
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(entity, id); R.1Xst &i
} rvwy~hO"
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publicObject get(finalClass entity, I/UQ' xx
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finalSerializable id){ wh~sZ
return getHibernateTemplate().get uf@U:V
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(entity, id); h#3m4<w(9
} |j_`z@7(
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publicList findAll(finalClass entity){ CJqc\I~
return getHibernateTemplate().find("from E:VGji7s
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" + entity.getName()); `%E9xcD%
} ~r`Wr`]_ z
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publicList findByNamedQuery(finalString ;WI]vn
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namedQuery){ z*.v_Mx
return getHibernateTemplate "jZm0U$,*
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().findByNamedQuery(namedQuery); cj(X2L
} hswTn`f
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publicList findByNamedQuery(finalString query, mpef]9
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finalObject parameter){ &
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return getHibernateTemplate ]R Mb,hJ
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().findByNamedQuery(query, parameter); "oE* 9J?e
} '>^Xqn
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publicList findByNamedQuery(finalString query, vO$ra5Z
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finalObject[] parameters){ Sa}D.SBg
return getHibernateTemplate w4:<fnOM
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().findByNamedQuery(query, parameters); 56s*A*z$
;
} v>WB FvyD
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publicList find(finalString query){ cjg=nTsBA
return getHibernateTemplate().find 4
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(query); #O</\|aH)i
} !s-/0ugZ
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publicList find(finalString query, finalObject Y(GW0\<
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parameter){ >}F? <JB
return getHibernateTemplate().find ${e&A^h
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(query, parameter); #K`B<2+T
} /w~C~6z
@!
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public PaginationSupport findPageByCriteria {aJz. `u\
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(final DetachedCriteria detachedCriteria){ {mYx
return findPageByCriteria ma7fDo0,`h
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); zH+<bEo=1=
} P|N?OocE
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public PaginationSupport findPageByCriteria [s %\.y(q
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(final DetachedCriteria detachedCriteria, finalint p#M!S2&z
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startIndex){ B&nw#saz.
return findPageByCriteria Ai jUs*n 2
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(detachedCriteria, PaginationSupport.PAGESIZE, 3"B+xbe=
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startIndex); U$$3'n
} O<a3DyUa;
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public PaginationSupport findPageByCriteria u<q)SQ1
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(final DetachedCriteria detachedCriteria, finalint Vw?P.4
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pageSize, ]n1D1
finalint startIndex){ y<uE-4
return(PaginationSupport) *(VbPp_H_
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getHibernateTemplate().execute(new HibernateCallback(){ DJJZJ}7
publicObject doInHibernate Wy,"cT
w#d} TY
(Session session)throws HibernateException { 0hZxN2r
Criteria criteria = T]X{@_
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detachedCriteria.getExecutableCriteria(session); sKCGuw(mh
int totalCount = $Q,n+ /
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((Integer) criteria.setProjection(Projections.rowCount Q^ q=!/qQ
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()).uniqueResult()).intValue(); _"v~"k 90^
criteria.setProjection :28@J?jjO
S
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(null); _3zU,qm+
List items = zCM^r <Kr
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criteria.setFirstResult(startIndex).setMaxResults %g5jY%dg.r
@6[x%j/!bt
(pageSize).list(); z}mvX.j7
PaginationSupport ps = ?PYNE
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new PaginationSupport(items, totalCount, pageSize, u-1@~Z
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startIndex); >T(M0Tkt
return ps; 5GUH;o1m
} wz)m{:b<
}, true); =yo=q)W
} H WOek"}Z[
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public List findAllByCriteria(final \cFAxL(
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DetachedCriteria detachedCriteria){ taBO4LV
return(List) getHibernateTemplate lWIv(%/@
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().execute(new HibernateCallback(){ r8<JX5zyuo
publicObject doInHibernate {Wr\DVp
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(Session session)throws HibernateException { (J/>Gy)d
Criteria criteria = d[yrNB6|
r \9:<i8
detachedCriteria.getExecutableCriteria(session); i~(#S8U4d
return criteria.list(); cyDiA(ot&
} ~S!L!qY
}, true); M$gvq:}kt
} # e$\~c Pd
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public int getCountByCriteria(final ^v#+PyW
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DetachedCriteria detachedCriteria){ }t}38%1i
Integer count = (Integer) M2a}x+5'
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getHibernateTemplate().execute(new HibernateCallback(){ G|<] Ma9x
publicObject doInHibernate |F3vRt@
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(Session session)throws HibernateException { |c]> Q
Criteria criteria = +|)zwe
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detachedCriteria.getExecutableCriteria(session);
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return K@y-)I2]
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criteria.setProjection(Projections.rowCount @ 8A{ 9i
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()).uniqueResult(); r
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} $Gr4sh!cE
}, true); }FuVY><l
return count.intValue(); OE5 X8DqQe
} d5N)^\z
} BW+qp3 k\
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用户在web层构造查询条件detachedCriteria,和可选的
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 x|&[hFXD
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PaginationSupport的实例ps。 f|;HS!$
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ps.getItems()得到已分页好的结果集 QxP` f KC8
ps.getIndexes()得到分页索引的数组 oB hL}r
ps.getTotalCount()得到总结果数 6(!,H<bON
ps.getStartIndex()当前分页索引 GZ;Z
ps.getNextIndex()下一页索引 <m-Ni
ps.getPreviousIndex()上一页索引 ^[k6]1h
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 .N?|t$J
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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 BA`kxL/x
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一下代码重构了。 |DdW<IT`0
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我把原本我的做法也提供出来供大家讨论吧: #JX|S'\x
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首先,为了实现分页查询,我封装了一个Page类: A- <.#
java代码: pO-)x:Wg
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/*Created on 2005-4-14*/ 3|z;K,`Fw
package org.flyware.util.page; _rWTw+
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/** 55u^u F
* @author Joa [kU[}FT
* [qc6Q:
*/ z{<q0.^EFh
publicclass Page { Lx4H/[$6D
l,~ N~?
/** imply if the page has previous page */ # UP,;W
privateboolean hasPrePage; b*$o[wO9
-NI@xJO4(;
/** imply if the page has next page */ &**.naSo
privateboolean hasNextPage; i&AXPq>`
jb6ZAT<8
/** the number of every page */ 06j)P6Iju
privateint everyPage; dqK
@Reh?]# v
/** the total page number */ P^o"PKA
privateint totalPage; j:\_*f
=qVAvo'
/** the number of current page */ KJ05Zx~uma
privateint currentPage; Rwi5+;N
,sy/rV
/** the begin index of the records by the current \f<thd*bC
*axza~d
query */ =#PudF.\
privateint beginIndex; a*e|>p DO
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/** The default constructor */ {BwN4r46
public Page(){ :;#c:RKi:
' ]H#0.
} :7'0:'0$t
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/** construct the page by everyPage T!O3(
* @param everyPage cmC&s'/8`D
* */ TO;]9`~;Mu
public Page(int everyPage){ 3mnL V*aRt
this.everyPage = everyPage; J>&dWKM3
} d&3I>E$UP
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/** The whole constructor */ 4'u|L&ow
public Page(boolean hasPrePage, boolean hasNextPage, .x9nWa
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int everyPage, int totalPage, #|2g{7g*
int currentPage, int beginIndex){ qoyGs}/I8
this.hasPrePage = hasPrePage; g^|_X1{
this.hasNextPage = hasNextPage; O,z%7><
this.everyPage = everyPage; 1tK6lrhj
this.totalPage = totalPage; d#$i/&gE
this.currentPage = currentPage; FCw
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this.beginIndex = beginIndex; 2* cKFv{
} FnU{C= P
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/**
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* @return ,L;c{[*rh
* Returns the beginIndex. N'W>pU
*/ j4hUPL7
publicint getBeginIndex(){ ,_7tRkn
return beginIndex; +[go7A$5
} ;z=C^'
I n%yMH8
/** OW5|oG
* @param beginIndex \c`r9H^v{
* The beginIndex to set. P+h<{%:*
*/ _jI)!rfb
publicvoid setBeginIndex(int beginIndex){ >0G}, S
this.beginIndex = beginIndex; $y |6<
} s(DaPhL6Qm
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/** 6T
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* @return mfi'>o#
* Returns the currentPage. z 4OR
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*/ -
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publicint getCurrentPage(){ '}[L sU
return currentPage; c^/?VmCQ}
} nV6g]#~@
g960;waz3
/** ri_6wbPp
* @param currentPage I<o4 l[--
* The currentPage to set. ~+NFWNgN
*/ \|4MU"ri
publicvoid setCurrentPage(int currentPage){ J}` $WL:
this.currentPage = currentPage; )^a#Xn3z
} [/`Hz]R
$/sZYsN~T
/** Q\th8/ /
* @return 'm.XmVZL%
* Returns the everyPage. t7`Pw33#kY
*/ _O71r}4
publicint getEveryPage(){ 2ZFKjj
return everyPage; T<~[vjA
} iZqFVr&JF
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/** Rhxm)5 +
* @param everyPage loVvr"&g
* The everyPage to set. XzwQ,+IAr
*/ Zvw3C%In
publicvoid setEveryPage(int everyPage){ AG!a=ufc0
this.everyPage = everyPage; \7?MUa.4
} AZ@Zo'
Bwvc@(3v
/** q|_ 5@Ly
* @return !ES#::;z?
* Returns the hasNextPage. LR?#H)$
*/ vnOF$6n
publicboolean getHasNextPage(){ rMFf8D(Y
return hasNextPage; (N>ew)Ke
} BY2txLLB
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/** uS10P7N}
* @param hasNextPage 9>Z#o<*_/
* The hasNextPage to set. ])";Z
*/ K%#C+`Ij
publicvoid setHasNextPage(boolean hasNextPage){ =-&iF
this.hasNextPage = hasNextPage; &:{yf=
} CAObC%
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/** "f$A0RL
* @return l.'E\3Bo
* Returns the hasPrePage. #NxvLW/
*/ hA19:H=7R0
publicboolean getHasPrePage(){ m!>'}z
return hasPrePage; bWzc=03
} yxq!.72
h |
/** R$3+ 01j|
* @param hasPrePage d-2I_ )9
* The hasPrePage to set. :fQ*'m,
*/ ~./u0E
publicvoid setHasPrePage(boolean hasPrePage){ I z@x^s
this.hasPrePage = hasPrePage; FnU;n
} nff ]Y$FB
q\=[v
/** 5~6y.S
* @return Returns the totalPage. F?4'>ZW
* *qOCo_=P8
*/ ;a77YLTQ
publicint getTotalPage(){ &3/H
P)*<]
return totalPage; jWCC`0
T
} <qiap2
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/** O!yn
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* @param totalPage ^^(ZK 6 d
* The totalPage to set. _!Q\Xn
*/ -$p-o
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publicvoid setTotalPage(int totalPage){ Zdz GJ[$
this.totalPage = totalPage; 4vJIO{m
} +Uk.|@b=-V
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} wBGxJ\+M
u _^=]K;
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bHG>SW\]`?
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 ?':'zT
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个PageUtil,负责对Page对象进行构造: FkkB#Jk4
java代码: 0`=?ig_
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/*Created on 2005-4-14*/ 6lFs N2
package org.flyware.util.page; K 6Ua~N^
>,1LBM|0u
import org.apache.commons.logging.Log; Y5pNKL
import org.apache.commons.logging.LogFactory; T!E LH!
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/** <H#K `|Ag
* @author Joa j3F=P
* k}gs;|_
*/ E':Z_ ^4
publicclass PageUtil { zK;t041e
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privatestaticfinal Log logger = LogFactory.getLog ?Fw/c0
\`x'g)z(i
(PageUtil.class); a#$%xw
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/** KfS^sT
* Use the origin page to create a new page } 4^UVdz
* @param page >{8H==P
* @param totalRecords ~;` #{$/C&
* @return 6dlPS{H#U
*/ zD|W3hL2&
publicstatic Page createPage(Page page, int 4'*K\Ul).H
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totalRecords){ #nz$RJsX
return createPage(page.getEveryPage(), 3~'F^=T.Y
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page.getCurrentPage(), totalRecords); &GAx*.L
} aKZD4;
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/** {F[Xe_=#"
* the basic page utils not including exception %m`QnRX?D
ij^!TY[0
handler QkAwG[4
* @param everyPage 64@s|m*
* @param currentPage r8$TT\?~
* @param totalRecords :gC2zv
* @return page 5#PhaVc
*/ tp&iOP6O
publicstatic Page createPage(int everyPage, int ]y
e
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currentPage, int totalRecords){ f|)t[,c
everyPage = getEveryPage(everyPage); NST6pu\,U
currentPage = getCurrentPage(currentPage); 03T.Owd
int beginIndex = getBeginIndex(everyPage, $Tza<nA
sjGZ
,?%
currentPage); 7\lb+^$
int totalPage = getTotalPage(everyPage, HVpaVM
6h%(0=^
totalRecords); CTYkjeej
boolean hasNextPage = hasNextPage(currentPage, Yn/-m
Z
1F/&Y}X
totalPage); @ So"(^
boolean hasPrePage = hasPrePage(currentPage); ~sD'pS
c#Bde-dh
returnnew Page(hasPrePage, hasNextPage, m` cG&Ar5
everyPage, totalPage, 1<UQJw45
currentPage, o6oYJ`PY
NGu]|p
beginIndex); mLSAi2Y
} +l\Dp
TrW3@@}j
privatestaticint getEveryPage(int everyPage){ R
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return everyPage == 0 ? 10 : everyPage; @UX`9]-P
} HN+z7 Q8hH
U@WT;:.T
privatestaticint getCurrentPage(int currentPage){ i^(<E0vS
return currentPage == 0 ? 1 : currentPage; oZCO$a
} HYS7=[hv6
Qd&j~cG@
privatestaticint getBeginIndex(int everyPage, int so*7LM?ib>
\9DTf:!4Z
currentPage){ VTU-'q
return(currentPage - 1) * everyPage; Rx.0P6s
} nYHk~<a
J4<*KL~a
privatestaticint getTotalPage(int everyPage, int :%gBcL9T
l3,|r QD
totalRecords){ R0WJdW#
int totalPage = 0; 3h&s=e!
Z)<>d.
if(totalRecords % everyPage == 0) =z+zg^wsT
totalPage = totalRecords / everyPage; o<y7Ut
else .?qS8:yA
totalPage = totalRecords / everyPage + 1 ; c<=1,TB"-_
U\N`[k.F
return totalPage; bZ)Jgz
} ;FUd.vg{
n"JrjvS
privatestaticboolean hasPrePage(int currentPage){ 9Z=Bs)-y.
return currentPage == 1 ? false : true; Y`wi=(
} 4Hw8w7us:
IaB
A 2
privatestaticboolean hasNextPage(int currentPage, #X+)
6m9Z5:xG
int totalPage){ B!Y;VdX
return currentPage == totalPage || totalPage == fg2}~02n
A+'j@c\&!
0 ? false : true; (+@H !>r$$
} 4s~o
01J.XfCd6
H:`r!5&Qb5
} V>hy5hDpH
BmZd,}{
<M=K!k
$d'Gh2IGA
<_+8 c{G
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 BN=,>-O%
VH/_0
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 }.#C9<"}
?Gb
18m
做法如下: #/aWGx_
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 j JW0a\0
x|Dj
的信息,和一个结果集List: S}>rsg!
java代码: lp6GiF
7Y-GbG.'
rei<{woX
/*Created on 2005-6-13*/ qz 'a.]{=
package com.adt.bo; Gc>\L3u
)gE:@3
import java.util.List; 5i0<BZDTef
q
o'1Pknz
import org.flyware.util.page.Page; GYBM]mW^ W
fQ<V_loP.@
/** [bAv|;
* @author Joa m2_B(-
*/ W6Hiqu+
publicclass Result { (t <Um
Vd
8u>E(Vmpu
private Page page; PpbW+}aCF
SkY|.w.
private List content; %FwLFo^v
PffRV7qU0
/** BQm H9g|2
* The default constructor T =:^k+
*/ E|No$QO)
public Result(){ I)6)~[:'
super(); B!,})F$x
} T^"d%au
b747 eR 7E
/** lGxG$0`;;
* The constructor using fields 46*?hA7@r(
* "kMpa]<c-6
* @param page bH&[O`vf
* @param content Ls9G:>'rR
*/ doG&qXw
public Result(Page page, List content){ )yjHABGJ
this.page = page; &AW?!rH
this.content = content; `jP6;i
} DJeG
b.$Gc!g
/** ]R0^
}sI
* @return Returns the content. f F?=W
*/ 7[Y<5T]
publicList getContent(){ K2&pTA~OR
return content; |[gnWNdR$M
} |g@1qXO3
MLUq"f~ N
/** 1<lLE1fk
* @return Returns the page. Nj?,'?'O}
*/ <#:"vnm$j
public Page getPage(){ 't
wMvm
return page; pCv=rK@
} .t\5H<z
m|'TPy
/** fuQ?@F
* @param content *8Gx_$t&
* The content to set. d"$ \fL
*/ R:11w#m7w
public void setContent(List content){ HdVGkv/
this.content = content; 6zyozJA
} I9_tD@s"(
)PZ'{S
/** e KET8v[
* @param page 0?k/vV4
* The page to set. JrO2"S
*/ O GSJR`yT
publicvoid setPage(Page page){ RzXxnx)]q
this.page = page; X|X6^}
} o: TO[
} nsYS0
V+_L9
Dg\fjuK9
a Z
^SK|E
WnA]gyc
2. 编写业务逻辑接口,并实现它(UserManager, ^oM*f{9
+b
1lCa_
UserManagerImpl) n
,`!yw
java代码: iz>a0~(K
pS9CtQqvgy
Ju+r@/y%
/*Created on 2005-7-15*/ G.1pg]P!
package com.adt.service; M++*AZ
A-uEZj_RD=
import net.sf.hibernate.HibernateException; r'-)@|
Jo_h?{"L{
import org.flyware.util.page.Page; ?:~ `?
wC;N*0Th
import com.adt.bo.Result; u[y>DPPx
W +C\/
/** R/U"]Rc
* @author Joa tPc '#.
*/ u.R:/H<>~
publicinterface UserManager { OE WIP
mq>Ag
public Result listUser(Page page)throws "@DCQ
W.{#Pg1Da
HibernateException; HX?5O$<<N
EPW
Iu)A
} b>?X8)f2e
oljl&tuQy
+ ,0RrD )
G
?H`9*y
7'd_]e-.
java代码: $U3s:VQ '
Xfk&{zO-j
xqX~nV#TB
/*Created on 2005-7-15*/ }>fL{};Z"
package com.adt.service.impl; 4,
8gf2
-TSn_XE
import java.util.List; >cQ*qXI0
qbpvTTF
import net.sf.hibernate.HibernateException; O]90F
g.Z>9(>;Y
import org.flyware.util.page.Page; ~\(U&2t
import org.flyware.util.page.PageUtil; r)q6^|~47
j'I$F1>Te
import com.adt.bo.Result; Xb5n;=)
import com.adt.dao.UserDAO; h{VCx#!]
import com.adt.exception.ObjectNotFoundException; bo`w(h_
import com.adt.service.UserManager; Fn yA;,*
#P<v[O/rA
/** JEGcZeq)
* @author Joa 26&^n
Uy
*/ AS'a'x>8>,
publicclass UserManagerImpl implements UserManager { 79z(n[^
RV.*_FG
private UserDAO userDAO; 52,p CyU
wqK>=Ri_
/** [-=PK\ B
* @param userDAO The userDAO to set. `fj(xrI
*/ iO(9#rV
publicvoid setUserDAO(UserDAO userDAO){ Atzp\oO
this.userDAO = userDAO; dq[j.Nmq
} FD,M.kbg
/k l0(='
/* (non-Javadoc) \M'b%
* @see com.adt.service.UserManager#listUser J+kxb"#d
)W(?wv!,
(org.flyware.util.page.Page) !i2=zlpb[
*/ ?yU|;my
public Result listUser(Page page)throws &Dgho
Jr==AfxyT
HibernateException, ObjectNotFoundException { &1{RuV&t
int totalRecords = userDAO.getUserCount(); #swzZyM$
if(totalRecords == 0) 3#j%F
throw new ObjectNotFoundException W -8<sv$b
{;=I69X
("userNotExist"); uL1e?
page = PageUtil.createPage(page, totalRecords); ]4@_KKP
List users = userDAO.getUserByPage(page); y}R{A6X)
returnnew Result(page, users); Ot`jjZ&
} GTyS8`5E*
j|A *rzL8
} { %vX/Ek
"W?k~.uw
<}L`d(E@f
k:nr!Y<
[>=D9I@~
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 K, WNM S
4w}\2&=
询,接下来编写UserDAO的代码: m1heU3BUWU
3. UserDAO 和 UserDAOImpl: !-m(1
java代码: S`)KC-
MMN2XxS
QS4sSua
/*Created on 2005-7-15*/ {+0]diD
package com.adt.dao; n{6XtIoYq
snK$? 9vh
import java.util.List; Zm>Q-7r9
k3da*vwE
import org.flyware.util.page.Page; \SHYwD}*Pr
A|,\}9)4X[
import net.sf.hibernate.HibernateException; ce0TQ
5hUYxF20h8
/** 8$io^n\i
* @author Joa |CexP^;!U
*/ bN`oQ.Z 4
publicinterface UserDAO extends BaseDAO { hWfJh0I
rW0# 6
publicList getUserByName(String name)throws f<=
#WV
<x,u!}5J
HibernateException; F42r]k
@F]6[
publicint getUserCount()throws HibernateException; Cg
|_) _w
Oz#$x
publicList getUserByPage(Page page)throws 3;zJ\a.+
m"t\@f
HibernateException; ^/47*vcN5
Ek~Qp9B
} AU)"L_
i}
R] tHd=kf
N)K};yMf
E ~<SEA
oJ ~ZzW
java代码: QrDzfe[
,B(UkPGT
#I|Vyufw
/*Created on 2005-7-15*/ LYhgBG,
package com.adt.dao.impl; W$O^IC
*6sB$E_y
import java.util.List; "
;_bB"q*
!@{_Qt1
import org.flyware.util.page.Page; ^>gRK*,
GNS5v-"H
import net.sf.hibernate.HibernateException; [u;]J*
import net.sf.hibernate.Query; kj~)#KDN
%6j|/|#]
import com.adt.dao.UserDAO; 0}2Uj>!i
LyH8T'C~
/** OD-CU8X9
* @author Joa B q+RFo
*/ `<i|K*u
public class UserDAOImpl extends BaseDAOHibernateImpl Z$ Fh4
>*(4evU
implements UserDAO { UK*+EEv
Ir|Q2$W2^c
/* (non-Javadoc) {9vvj
* @see com.adt.dao.UserDAO#getUserByName <6Q]FH!6
|}b~ss^
(java.lang.String) *[*LtyCQt4
*/ r483"k(7
publicList getUserByName(String name)throws i;;CU9`E2q
dE!{=u(!i
HibernateException { B(wk $2
String querySentence = "FROM user in class W"? |O Q'
#Z;ziM:
com.adt.po.User WHERE user.name=:name"; jhjGDF
Query query = getSession().createQuery 5gARGA
58,_
(querySentence); g6o-/A!Q3
query.setParameter("name", name); *M\Qt_[
return query.list(); !/znovoD
} 6e&Y%O'8
]`0(^)U&
/* (non-Javadoc) WY_}D!O
* @see com.adt.dao.UserDAO#getUserCount() 1dh_"/
*/ d|k6#f-E
publicint getUserCount()throws HibernateException { BoYWx^VHx^
int count = 0; Q%KH^<
String querySentence = "SELECT count(*) FROM ny%-u&1k
7m_Jb5
user in class com.adt.po.User"; ;Xg6'yxJ
Query query = getSession().createQuery ks<gSCB
Idop!b5!
(querySentence); A(X~pP&oF
count = ((Integer)query.iterate().next 7D\#1h
Rcs7 'q5
()).intValue(); m663%b(5>
return count; u`dWU}m)
} pj;cL]L
p)vyZY[
/* (non-Javadoc) EQ1wyKZS2g
* @see com.adt.dao.UserDAO#getUserByPage GQhzQM1HS
:A
$%5;-kO
(org.flyware.util.page.Page) =;!C7VS
*/ <use+C2
publicList getUserByPage(Page page)throws ~j}di^<{
cG1-.,r
HibernateException { 2c@4<kyfP
String querySentence = "FROM user in class /f~V(DK
| V Ps5
com.adt.po.User"; '<5Gf1 @|
Query query = getSession().createQuery YdX#`
34_:.QK-
(querySentence); <\!+J\YTA
query.setFirstResult(page.getBeginIndex()) J7W]Str
.setMaxResults(page.getEveryPage()); +C1/02ZJ
return query.list(); eyBLgJt8P
} pqFgi_2m
vS%o>"P
} (.4mX
t
w G[X*/v
5jD2%"YUV
9$8B)x
+:pjQ1LsJ
至此,一个完整的分页程序完成。前台的只需要调用 ~f0Bu:A)
o#gb+[
userManager.listUser(page)即可得到一个Page对象和结果集对象 'qwFVP
m-S4"!bl
的综合体,而传入的参数page对象则可以由前台传入,如果用 eE5U|y)_
DcaVT]"
webwork,甚至可以直接在配置文件中指定。 d]6.$"\"p
?.~E:8
下面给出一个webwork调用示例:
hz{=@jX
java代码: U">w3o|
CM?dB$AwX
J[2c[|[-
/*Created on 2005-6-17*/ 6,*hzyy}Qu
package com.adt.action.user; | YmQO#''
<x@brXA
import java.util.List; / =&HunaxI
Q
laz3X,P
import org.apache.commons.logging.Log; yM>:,T S
import org.apache.commons.logging.LogFactory; QxG:NN;jW
import org.flyware.util.page.Page; }wRHNBaEB
pYIm43r H
import com.adt.bo.Result; VSP6osX{
import com.adt.service.UserService; Wcd;B7OH
import com.opensymphony.xwork.Action; 4^\5]d!
8gWifx
#N
/** CIAHsbn.A
* @author Joa Lb;:<
*/ SVWtKc<
publicclass ListUser implementsAction{ 4%>iIPXi.(
d6,SZ*AE
privatestaticfinal Log logger = LogFactory.getLog .E}fk,hLB
k44sV.G4L
(ListUser.class); U;p" x^U`
Lpd q^X
private UserService userService;
b$\3Y'":
N@Pf \D
private Page page; '*H&s
%_C!3kKv~
privateList users; 6&/n/g
sT:$:=
/* ;zVtJG`
* (non-Javadoc) \nT, NV11
* Xr'Y[E[
* @see com.opensymphony.xwork.Action#execute() #AHX{<
*/ 60p*$Vqy
publicString execute()throwsException{ +Qy0K5Ee
Result result = userService.listUser(page); >8h14uCk
page = result.getPage(); .`qw8e}y#'
users = result.getContent(); # rnO=N8
return SUCCESS; WgX9k J
} vt)u`/u
fui;F"+1
/** Za,rht
* @return Returns the page. )fSO|4
*/ a{*r^m'N
public Page getPage(){ Dn/{ s$\
return page; j)?[S
} '4 T}$a"i
n<RvL^T=
/** Yzo_ZvL
* @return Returns the users. g=W1y
*/ K[}5bjh>
publicList getUsers(){ k~
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return users; -pEt=
} S5B12P
i2$7nSQ9
/** x?T.ItW:K
* @param page JAPiR=
* The page to set. L[v-5u)
*/ nO-1^HUl
publicvoid setPage(Page page){ $&IF#uDf
this.page = page; ]6JI((
} JBzRL"|
ig
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/** Y:UDte[Lb
* @param users ErZYPl
* The users to set. 3%`asCW$
*/ ?+6w8j%\
publicvoid setUsers(List users){ `Hj{XIOx
this.users = users; >IZ|:lsxE
} 2Lravb3
l6o?(!:!%
/** ['1JNUX
* @param userService _19x`J3
* The userService to set. j;%RV)e
*/ ;&="aD
publicvoid setUserService(UserService userService){ )X-~+X91S
this.userService = userService; Iu(j"b#
} eYSVAj
} 79}voDFd
QN!.~>
1 /@lZ
g+CTF67
::'DWD1
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, MZ9{*y[z
oEfy{54
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 @|A
wT
c;RB!`9"
么只需要: &dA{ <.
java代码: [Ol}GvzJ7
#fT1\1[]
~r(/)w\
<?xml version="1.0"?> (y^[k {#
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork o]Ln:k l
>b^|SL
1.0//EN" "http://www.opensymphony.com/xwork/xwork- T2Duz,
5Z
(1&
1.0.dtd"> gie.K1@|
VE_% /Fs,
<xwork> "XvM1G&s`
|n9q4*dN
<package name="user" extends="webwork- "v%|&@
R
2.y=P8N
interceptors"> XLG6f(B= F
{~cG'S Y%
<!-- The default interceptor stack name z'iAj
$inpiO|s
--> D)0pm?*5A
<default-interceptor-ref IvJ;9d
|q0MM^%"
name="myDefaultWebStack"/> ZH
o#2{F
]U9f4ODt
<action name="listUser" Mv\odf\]
Z{'.fq2A
class="com.adt.action.user.ListUser"> Os1o!w:m5
<param 6x6xv:\
c5KJ_Nfi
name="page.everyPage">10</param> o>3g<-ul
<result #HgXTC
oh>X/uj
name="success">/user/user_list.jsp</result> DM*GvBdR
</action> nMz~.^Q-
B Q)1)8r
</package> y7&8P8R
R9dC$Y]\M
</xwork> g 0=Q>TzY
zYL</!6a[
PxqRb
|Wo_5|E
6[iu CMOZ
NTj: +z0
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 ,7wxVR%Ys
BK+(Uf;g
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。 HizMjJ|
Muhq,>!U
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 tA,#!Z0
OfSy _#aEK
S7/0B4[
WKHEU)'!
;t^8lC?>V
我写的一个用于分页的类,用了泛型了,hoho oM ')NIW@
9!aQ@ J^
java代码: NrC(.*?m
h[Hn*g
M=HP!hn
package com.intokr.util; MV+S.`R
>
`uk2QdC
import java.util.List; !a(#G7zA
wK0= I\WN9
/** dcK7Dd->
* 用于分页的类<br> #<^ngoOj
* 可以用于传递查询的结果也可以用于传送查询的参数<br> s:4<wmu4=
* hM":?Rx
* @version 0.01 W0++q=F
* @author cheng AX
{~A:B
*/ %`o3YR
public class Paginator<E> { k1EAmA
l
privateint count = 0; // 总记录数 "CS{fyJ
privateint p = 1; // 页编号 M*& tVG
privateint num = 20; // 每页的记录数 S6J7^'h
privateList<E> results = null; // 结果 yUZ;keQ_Tw
!A5UT-
/** $U{\T4
* 结果总数
]+ \]2`?
*/ ?2;gmZd7
publicint getCount(){ i]qVT)j
return count; %Q)3*L
} Q@7-UIV|q
4{[cXM8*j
publicvoid setCount(int count){ |VY+!
this.count = count; xj1FCT2
} ]i}3`e?
3jH8pO^
/** E0g`
xf6c
* 本结果所在的页码,从1开始 _~^JRC[q
* |.]:#)^X?
* @return Returns the pageNo. d"7l<y5
*/ ev bqBb21b
publicint getP(){ W?*]'0
return p; %B;e7
UJ
} [c{/0*
} s0?RH
/** v|VfSLZTb
* if(p<=0) p=1 xB%Felz
* Rh:@@4<
* @param p B %|cp+/
*/ eyx;8v cM
publicvoid setP(int p){ k"J[mT$b
if(p <= 0) Tug}P K
p = 1; H;&^A5
this.p = p; >
xc7Hr~
} Z+zx*(X
>bKN$,Qen
/** b~M3j&
* 每页记录数量 b
r"47i
*/ !,f#oCL
publicint getNum(){ rUb`_ W@
return num; NAy3Zd}
} ^'UJ&UfX
B/*`u
/** r%*UU4xvB
* if(num<1) num=1 z}Qt6na]-
*/ i[gq8%
publicvoid setNum(int num){ sj)$o94=
if(num < 1) o6 FSSKM
num = 1; l'_P]@*
this.num = num; U%swqle4
} CB<i
KUr}?sdz
/** RJ#xq#l
* 获得总页数
\= M*x
*/ +) pO82
publicint getPageNum(){ )czuJ5
return(count - 1) / num + 1; s^
t1T&
} ews4qP
1gq(s2izy
/** ^|z
* 获得本页的开始编号,为 (p-1)*num+1 4FmT.P
*/ &x}a
publicint getStart(){ yv.UNcP?
return(p - 1) * num + 1; 0?D`|x_
} 4t(V)1+
m=Z1DJG
/** }CR@XD}[
* @return Returns the results. N2!HkUy2
*/ XO*|P\#^
publicList<E> getResults(){ qusX]Tstz
return results; 3Mvm'T:[
} E~=`Ac,G2
hFDY2Cp]D
public void setResults(List<E> results){ $'SWH+G
this.results = results; $6BD6\@
} yu3T5@Ww
^ Vl{IsY
public String toString(){ {8NnRnzU
StringBuilder buff = new StringBuilder .t/XW++
Ms^U`P^V~P
(); :hre|$@{a
buff.append("{"); E!d;ym
buff.append("count:").append(count); r!qr'Ht<
buff.append(",p:").append(p); Ig&=(Kmr
buff.append(",nump:").append(num); v&[Ff|>
buff.append(",results:").append 9=(*#gRd
J|DID+M
(results); 3y}0J @
buff.append("}"); &N{XLg>
return buff.toString(); dtK[H+
} pi>,>-Z
t)Iu\bP
} V~V_+
#q7`"E=M"
/cPezX