Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 :|($,3*
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 VD4S_qx
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 5=.7\#D
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 bXm:]?
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分页支持类: a[JZ5D
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java代码: rJp?d9B
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package com.javaeye.common.util;
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import java.util.List; 6i^0T
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publicclass PaginationSupport { o:f|zf>
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publicfinalstaticint PAGESIZE = 30; /o'oF
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privateint pageSize = PAGESIZE; =Y:5,.U
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privateList items; (T4k~T`3
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privateint totalCount; ?Ip$;s
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privateint[] indexes = newint[0]; ]~ >@%v&
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privateint startIndex = 0; bQ
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public PaginationSupport(List items, int XZ!cW=bqS
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totalCount){ \}n !yYh(
setPageSize(PAGESIZE); 0>8ZN!@K
setTotalCount(totalCount); /1H9z`qV
setItems(items); 4$qNcMdz
setStartIndex(0); `s#sE.=o
} _Eszr(zJ
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public PaginationSupport(List items, int CuF%[9[cT
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totalCount, int startIndex){ !7ph,/P$7
setPageSize(PAGESIZE); )Fw
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setTotalCount(totalCount); BJ_+z gf`
setItems(items); SxnIX/]J
setStartIndex(startIndex); Cca~Cq[%*(
} M
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public PaginationSupport(List items, int m
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totalCount, int pageSize, int startIndex){ 0EcC
setPageSize(pageSize); ecM4]U
setTotalCount(totalCount); myEGibhK
setItems(items); Fc34Y0_A
setStartIndex(startIndex); {d&X/tT
}
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publicList getItems(){ f)p>nW?Z
return items; @>qx:jx(-S
} fho=<|-
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publicvoid setItems(List items){
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this.items = items; wrZ7Sr!/V
} H9oXZSm
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publicint getPageSize(){ OpWC2t)
return pageSize; `@ VM<av
} ~0'_K1(H
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publicvoid setPageSize(int pageSize){ =F",D=
this.pageSize = pageSize; t~+{Hr) #y
} .Um?5wG~i
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publicint getTotalCount(){ ]%cHm4#m3
return totalCount; q\\8b{~
} "z{_hp{T^
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publicvoid setTotalCount(int totalCount){ gQ[]
if(totalCount > 0){ t1.zWe+C>3
this.totalCount = totalCount; 9^#zxmH)
int count = totalCount / =hZ&66
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pageSize; GY0XWUlC
if(totalCount % pageSize > 0) zR3lX}g
count++; I>YtWY|ed
indexes = newint[count]; SG(%d^x`R
for(int i = 0; i < count; i++){ Allt]P>
indexes = pageSize * 1`2);b{@
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i; pAUfG^v
} eCPKpVhP
}else{ Y1yvI
this.totalCount = 0; jFJW3az@z
} xy-$v
} "2vNkO##
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publicint[] getIndexes(){ ]|((b/L3
return indexes; I;Z`!u:+
} `ohF?5J,
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publicvoid setIndexes(int[] indexes){ +_-)0[+p
this.indexes = indexes; K8yyxJ
} iaaH9X
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publicint getStartIndex(){ fRv
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return startIndex; @y;tk$e
} kw}ISXz v
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publicvoid setStartIndex(int startIndex){ npG+#z
if(totalCount <= 0) mNBpb}
this.startIndex = 0; '^.=gTk
elseif(startIndex >= totalCount) ![X.%
this.startIndex = indexes [6/%V>EM
mAYr<=
[indexes.length - 1]; x=)30y3*;
elseif(startIndex < 0) UtGd/\:
this.startIndex = 0; qhn&;{{
else{ v @I^:I
this.startIndex = indexes <'4!G"_EP
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[startIndex / pageSize]; Ph!KL\
} U7f&N
} Ie`SWg*WL
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publicint getNextIndex(){ /O(;~1B
int nextIndex = getStartIndex() + qS/71Kv'
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pageSize; ^v'g ~+@o
if(nextIndex >= totalCount) E{k%d39>
return getStartIndex(); N:gstp
else xUYN\Pc-
return nextIndex; P".qL5
} -)->Jx:{
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publicint getPreviousIndex(){ ~V$5 m j
int previousIndex = getStartIndex() - n.H`1@
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pageSize; r<f-v_bxF
if(previousIndex < 0) "6Hjji@A
return0; "*>QxA%c4
else Z]> e & N
return previousIndex; C7*Yg$`{
} 0 *Yivx6
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} MgK(gL/&[
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抽象业务类 "F.J>QBd
java代码: ~zOU/8n
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/** }y=n#%|i.
* Created on 2005-7-12 VTX'f2\
*/ );.<Yf{c
package com.javaeye.common.business; zm^p7&ak$
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import java.io.Serializable; >8HRnCyp/
import java.util.List; &)'kX
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import org.hibernate.Criteria; Fb4S/_
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import org.hibernate.HibernateException; AxqTPx7`|
import org.hibernate.Session; x: wq"X
import org.hibernate.criterion.DetachedCriteria; 0BwQ!B.
import org.hibernate.criterion.Projections; Zo6a_`)d
import JC?V].) y5
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org.springframework.orm.hibernate3.HibernateCallback; [zt&8g
import =81Xt1,
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org.springframework.orm.hibernate3.support.HibernateDaoS L$07u{Q
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upport; hdDI%3vk3
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import com.javaeye.common.util.PaginationSupport; fHp#Gi3Lz
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public abstract class AbstractManager extends L1w4WFWO
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HibernateDaoSupport { 2F)OyE
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privateboolean cacheQueries = false; L7'X7WYf&
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privateString queryCacheRegion; x-k/rZ
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publicvoid setCacheQueries(boolean ^rb7`s#G
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cacheQueries){ T{2//$T?
this.cacheQueries = cacheQueries; ~9 nrS9)
} GdwHm
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publicvoid setQueryCacheRegion(String f*f9:xUY
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queryCacheRegion){ HUX+d4sg
this.queryCacheRegion = zT 40,rk
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queryCacheRegion; 6q7Y`%j
} {-Oc8XI/
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publicvoid save(finalObject entity){ 4h@of'
getHibernateTemplate().save(entity); z@LP9+?dE
} blS4AQ?b^
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publicvoid persist(finalObject entity){ M#IR=|P]
getHibernateTemplate().save(entity); x?$Y<=vT
} $O>MV
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publicvoid update(finalObject entity){ r!=VV!XZ
getHibernateTemplate().update(entity); 6!V* :.(
} "A$Y)j<#G
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publicvoid delete(finalObject entity){ D7oV&vXg
getHibernateTemplate().delete(entity); Lg53
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} p_N=V. w
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publicObject load(finalClass entity, r F-yD1
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finalSerializable id){ m)2U-3*iX
return getHibernateTemplate().load 7tnzgtal
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(entity, id); }gt~{9?c
} {RO=4ba{J
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publicObject get(finalClass entity, auv\fR :
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finalSerializable id){ m]vr|:{6/
return getHibernateTemplate().get a+Nd%hoe
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(entity, id); )FCqYCfk
} W6>uLMUa
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publicList findAll(finalClass entity){ %dQX d]
return getHibernateTemplate().find("from pu#<qD*w
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" + entity.getName()); {,-# ;A*yW
} djp(s$:{4
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publicList findByNamedQuery(finalString woKdI)f$
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namedQuery){ %(6Wr E5F6
return getHibernateTemplate XUHY.M
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().findByNamedQuery(namedQuery); Q.yoxq
} NI)nf;C
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publicList findByNamedQuery(finalString query, 4#uoPkLK
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finalObject parameter){ /cn_|DwN5
return getHibernateTemplate .BvV[`P
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().findByNamedQuery(query, parameter); $+j)
} 04TV./uA
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publicList findByNamedQuery(finalString query, 5=\b+<pE
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finalObject[] parameters){ aDESO5
return getHibernateTemplate sj~'.Zs%
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().findByNamedQuery(query, parameters); }ls>~uN
} ;8UHPDnst
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publicList find(finalString query){ Qpc>5p![3
return getHibernateTemplate().find #kA+Yqy\)
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(query); u/:@+rTV_
} .'M]cN~
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publicList find(finalString query, finalObject ~?FKww|_*J
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parameter){ `B~%TEvMh
return getHibernateTemplate().find D
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(query, parameter); Sk xaSJ"
} FK>rc3 q
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public PaginationSupport findPageByCriteria 9ZwhCsO
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria :Fh*4
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); vhKD_}}aP
} G8@%)$A
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public PaginationSupport findPageByCriteria |"arVde
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(final DetachedCriteria detachedCriteria, finalint mYZH]oo
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startIndex){ ke0Vy(3t{h
return findPageByCriteria O1QHG'00
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(detachedCriteria, PaginationSupport.PAGESIZE, {"s8X(#_sC
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startIndex); |e!Sm{#!
} &}WSfZ0{
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public PaginationSupport findPageByCriteria l ^{]pD
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(final DetachedCriteria detachedCriteria, finalint GerZA#
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pageSize, 7l?-2I'c
finalint startIndex){ >[[< 5$,T
return(PaginationSupport) tUzuel*
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getHibernateTemplate().execute(new HibernateCallback(){ ]:F]VRPT
publicObject doInHibernate _uDtRoI8
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(Session session)throws HibernateException { ?P}7AF
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Criteria criteria = FJ/kumq
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detachedCriteria.getExecutableCriteria(session); CpA=DnZ
int totalCount = j5AW}
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((Integer) criteria.setProjection(Projections.rowCount =r`>tWs
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()).uniqueResult()).intValue(); )U5AnL
criteria.setProjection { 2-w<t
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(null); vAX %i( 4
List items = 7z`)1^M
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criteria.setFirstResult(startIndex).setMaxResults ofsua?lSe
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(pageSize).list(); 233jT@Z
PaginationSupport ps = Xq9%{'9
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new PaginationSupport(items, totalCount, pageSize, ZM0vB% M|
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startIndex); %G>*Pez%
return ps; fAXF_wj
} &!_>J0
}, true); A+>+XA'
} zGA#7W2?0
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public List findAllByCriteria(final S9-FKjU
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DetachedCriteria detachedCriteria){ PU[]
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return(List) getHibernateTemplate </Ja@%
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().execute(new HibernateCallback(){ |}=xA%)
publicObject doInHibernate IOomBy:
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(Session session)throws HibernateException { s@V4ny9x
Criteria criteria = L~=h?C<
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detachedCriteria.getExecutableCriteria(session); g=Rl4F]
return criteria.list(); v:|_!+g:
} yO.q{|kX
}, true); [<rV
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} =wtu
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public int getCountByCriteria(final Gg$4O 8
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DetachedCriteria detachedCriteria){ D.su^m_1
Integer count = (Integer) yp9vgUs
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getHibernateTemplate().execute(new HibernateCallback(){ I82GZL
publicObject doInHibernate ~nDbWv"
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(Session session)throws HibernateException { 8`Ih>
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Criteria criteria = Vq4g#PcG
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detachedCriteria.getExecutableCriteria(session); }6b" JoC
return |$
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criteria.setProjection(Projections.rowCount rU/8R'S
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()).uniqueResult(); ;#)sV2F\&
} %1h%#/#[
}, true); "!,)Pv
return count.intValue(); +@G#Z3;l!
} XN|[8+#U<@
} ]?c9;U
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用户在web层构造查询条件detachedCriteria,和可选的 yVfF
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 0(qtn9;=2
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PaginationSupport的实例ps。
}o[NB
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ps.getItems()得到已分页好的结果集 tY@+d*u
ps.getIndexes()得到分页索引的数组 =W[M=_0u
ps.getTotalCount()得到总结果数 q8SHFKE
ps.getStartIndex()当前分页索引 kltorlH
ps.getNextIndex()下一页索引 /`s{!t#Y
ps.getPreviousIndex()上一页索引 ,,8'29yEq
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 p54e'Zb
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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
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一下代码重构了。 c8h71Cr
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我把原本我的做法也提供出来供大家讨论吧: "N3!!3
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首先,为了实现分页查询,我封装了一个Page类: n,#o6ali>
java代码: L'HO"EZFj
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/*Created on 2005-4-14*/ bQ`2ll*(
package org.flyware.util.page; 3[UaK`/1C
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/** a|-B# S
* @author Joa Hy1pIUsx
* ?$@E}t8g\
*/ 09 vm5|
publicclass Page { 9~v#]Q}Z}4
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/** imply if the page has previous page */ zP>=K
privateboolean hasPrePage; J\?d+}hynX
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/** imply if the page has next page */ LG
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privateboolean hasNextPage; Og1Hg
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/** the number of every page */ /Py`a1
privateint everyPage; GrA}T` ]
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/** the total page number */ w|U7pUz
privateint totalPage; Of;$
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/** the number of current page */ ;y.<I&
privateint currentPage; ^.~ F_
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/** the begin index of the records by the current 7
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query */ |?LUt@r;
privateint beginIndex; /mQ9}E4X
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/** The default constructor */ nXW]9zC"/
public Page(){ w1)SuMFK_
;m}o$`
} Fv3:J~Yf
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/** construct the page by everyPage i&Me7=~
* @param everyPage eR!K8W
* */ }/VSIS@Z
public Page(int everyPage){ 78O5$?b;#
this.everyPage = everyPage; e
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} S%7%@Qs"%
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/** The whole constructor */ +\66; 7]s
public Page(boolean hasPrePage, boolean hasNextPage, S^ JUQx7
*Edr\P
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int everyPage, int totalPage, O;RNmiVoq
int currentPage, int beginIndex){ :snn-e0l
this.hasPrePage = hasPrePage; l`vr({A
this.hasNextPage = hasNextPage; &$. x1$%
this.everyPage = everyPage; l]mn4cn3
this.totalPage = totalPage; 0@2pw2{Ru
this.currentPage = currentPage; 3L%g2`
this.beginIndex = beginIndex; &:Sb$+z
} 1~9AQ[]w8
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/** 3bMUsyJ 2
* @return Zq>}SR
* Returns the beginIndex. i
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*/ R,ddH[3
publicint getBeginIndex(){ p&(~c/0
return beginIndex; x^JjoI2vf
} f n'N^
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/** dIDs~
* @param beginIndex bHH=MLZR:
* The beginIndex to set. (?pn2- Ip
*/ |cq%eN
publicvoid setBeginIndex(int beginIndex){ Z|a\rNv
this.beginIndex = beginIndex; -~ycr[}x
} 8v']>5S]#
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/** &)|3OJ'o
* @return Ue0Q| h
* Returns the currentPage. =Pgu?WU@
*/ QprzlxB
publicint getCurrentPage(){ "rIBy
return currentPage; ]qk/V:H:
} 7&9'=G
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/** ?#X`Eu
* @param currentPage 7w=%aW|
* The currentPage to set. wuTCdBu6hU
*/ ICgyCsZ,
publicvoid setCurrentPage(int currentPage){ u3H2\<
this.currentPage = currentPage; CfnRcnms
} `;R|SyrX
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/** '((Ll
* @return E5 0$y:
* Returns the everyPage. =7`0hS<@F
*/ W[3)B(Vq<E
publicint getEveryPage(){ xbA% 'p
return everyPage; ;{inhiySN
} 4GRmo"S
V
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/** :1wMGk
* @param everyPage 8_tMiIE-pS
* The everyPage to set. UI:{*N**Z
*/ 0|:Ic,
publicvoid setEveryPage(int everyPage){ <`q|6XWL
this.everyPage = everyPage; 3rZ" T
} ft[g1
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/** :*!u\lV \
* @return VBssn]w
* Returns the hasNextPage. ?s5zTT0U>$
*/ G?]E6R
publicboolean getHasNextPage(){ }x1mpPND
return hasNextPage; k852M^JP
} %6"b<
MAO
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/** Tf"DpA!_
* @param hasNextPage ]Nvtiw 6
* The hasNextPage to set. G1~|$X@@
*/ BifA&o%
publicvoid setHasNextPage(boolean hasNextPage){ bhSpSul
this.hasNextPage = hasNextPage; HJ5m5':a
} t{>66jm\R
j78xMGKO
/** 38Z"9
* @return 7Yxy2[
* Returns the hasPrePage. k&DHQvfB
*/
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publicboolean getHasPrePage(){ KX)xCR~
return hasPrePage; @6$r|:]G-
} uPV,-rm[F_
#Y}Hh7.<
/** ?/)5U}*M0T
* @param hasPrePage J6 [x(T
* The hasPrePage to set. GKY:"q&h
*/ J5Fg]O*
publicvoid setHasPrePage(boolean hasPrePage){ 7"xd'\c@
this.hasPrePage = hasPrePage; #G.3a]p}"
} 9zO3KT2
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/** ?GFxJ6!%I
* @return Returns the totalPage. 9v
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* RC (v#G
*/ Op)0D:BmR
publicint getTotalPage(){
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return totalPage; m4Wn$Z
} h0.Fstf]
qqzQKN
/** "}SERC7
* @param totalPage ;wQWt_OtuJ
* The totalPage to set. +zs6$OI]V
*/ U-FA^c;
publicvoid setTotalPage(int totalPage){ N0vd>b
this.totalPage = totalPage; z}bnw2d]
}
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} dWqFP
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}uHc7gTBF7
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 H;sQ]:.*]
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个PageUtil,负责对Page对象进行构造: 2/7=@>|
java代码: @eTsS%f2
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/*Created on 2005-4-14*/ |~HlNUPR
package org.flyware.util.page; pz&=5F
#Y5I_:k
import org.apache.commons.logging.Log; d(@A
import org.apache.commons.logging.LogFactory; ?J~JQe42
@&Nvb.5nT
/** KFZ[gqW8YY
* @author Joa z'qVEHc)
* pK8nzGQl7
*/ i`>X5Da5
publicclass PageUtil { 'd t}i<
]JD$fS=_
privatestaticfinal Log logger = LogFactory.getLog ^X&9"x)4
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(PageUtil.class); 87^
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/** \9}5}X_x.
* Use the origin page to create a new page 0wkLM-lN
* @param page q9
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* @param totalRecords aqM_t
* @return 4 P;O8KA5y
*/ v)d0MxSC
publicstatic Page createPage(Page page, int JG<3,>@%
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totalRecords){ m4DH90~a8
return createPage(page.getEveryPage(), Eo Urc9G2
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page.getCurrentPage(), totalRecords); @
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} -*lP1Nbp
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/** vQ/\BN
* the basic page utils not including exception d*>k
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cx,A.Lc
handler VjqdKQeVq
* @param everyPage 2SJh6U
* @param currentPage .V3Dql@z"
* @param totalRecords B<XPu=|
* @return page YgiGI
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*/ 4LjSDgA
publicstatic Page createPage(int everyPage, int 9AYe,R
Mdrv/x{
currentPage, int totalRecords){ H ZLOn
everyPage = getEveryPage(everyPage); X{xJ*T y'
currentPage = getCurrentPage(currentPage); JYr7;n'!
int beginIndex = getBeginIndex(everyPage, Qg>GW
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currentPage); 93Gur(j^
int totalPage = getTotalPage(everyPage, 4) iEj
02^(z6K'&?
totalRecords); G
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boolean hasNextPage = hasNextPage(currentPage, #@6L|$iX
[T}]Ma*CS
totalPage); N#)VD\m
boolean hasPrePage = hasPrePage(currentPage); Kg`x9._2
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returnnew Page(hasPrePage, hasNextPage, 4<g72| y
everyPage, totalPage, 'B5J.Xe:
currentPage, -fx88
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beginIndex); Hs}"A,V
} eH!|MHe
/e sk
privatestaticint getEveryPage(int everyPage){ "$IwQ
return everyPage == 0 ? 10 : everyPage; =P;;&j3Z
} !J=;Z9
).!14Gjo
privatestaticint getCurrentPage(int currentPage){ 0*;9CH=BE
return currentPage == 0 ? 1 : currentPage; '+I
2$xE
} wwcwYPeg
A%*DQ1N
privatestaticint getBeginIndex(int everyPage, int eAYW%a
uP=_-ZUW
currentPage){ . 02(O
return(currentPage - 1) * everyPage; #oroY.o
} b)hOzx
iRwW> a3/
privatestaticint getTotalPage(int everyPage, int q\b
?o!#_
K# i*9sM
totalRecords){ \m~\,em
int totalPage = 0; 30(m-D$K>9
"">fn(
if(totalRecords % everyPage == 0) 9poEUjBI
totalPage = totalRecords / everyPage; 'oiD#\t4
else )Kk(P/s
totalPage = totalRecords / everyPage + 1 ; Z:Y.":[
Qi
-KwL9J4u
return totalPage; d+m6-4[_k
} .xz,pn}
1|EU5<
privatestaticboolean hasPrePage(int currentPage){ !Zyx$2K
return currentPage == 1 ? false : true; E#{WU}
} [%iUg\'7d
KB,~u*~!
privatestaticboolean hasNextPage(int currentPage, /Xu;/MMpd3
4'{hI;&a&
int totalPage){ Fy_<Ui
return currentPage == totalPage || totalPage == %hQMC'c
vBnKu
0 ? false : true; YKw!pu=
} lq\'
W]!@Zlal
fs3-rXoB
} ycl>git]
X6Nm!od'
S QM(8*:X
(w#slTFT
6N%L8Q
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。 #lyM+.T
v`_i1h9p{
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 3!"b
guE
=!g/2;-or
做法如下: ezg^5o;
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 $||ns@F+
TJyH/C
的信息,和一个结果集List: qr'x0r|<>
java代码: BDm88<]
'!+P{
;*wT,2;
/*Created on 2005-6-13*/ \f /!
package com.adt.bo; Ere?d~8
\8>
import java.util.List; Y0Hq+7x
<m Ju v
import org.flyware.util.page.Page; TXd5v#_vo
SG
dfhno;
/** P|e:+G 7
* @author Joa *l> [`U+
*/ TbKP8zw{
publicclass Result { 5#TrCPi6A
P7'oXtW{o
private Page page; H9Y2n 0
( Lok
private List content; {[M0y*^64$
ba(arGZ+{
/** >%uAQiU
* The default constructor J{Y6fHFi
*/ _DPB?)!x
public Result(){ )K>Eniou
super(); ;mf4U85
} ] ?DDCew
a"0B?3*r46
/** Z&+NmOY4
* The constructor using fields 18DTv6?QG
* <ICZ"F`S
* @param page j!zA+hF(
* @param content
_'!aj+{
*/ d] b~)!VW
public Result(Page page, List content){ ~t'#n V
this.page = page; y-w2O]
this.content = content; p{iG{
} kZV^F*7
d&}pgb-Md
/** W4)kkJ
* @return Returns the content. 0Y2\n-`z
*/ g\ErJ+i
publicList getContent(){ f,Sth7y
return content; ?TvQ"Y}k
} Z~r[;={,
Yw6DJY
/** GY oZ$p" C
* @return Returns the page. !UBy%DN~k
*/ j y7
public Page getPage(){ %xf)m[JU=
return page; cU7rq j_
} gKmX^A5<
T?W[Z_D
/** ( MB`hk-d
* @param content M
(+.$uz
* The content to set. o .l;:
Un
*/ cqeR<len
public void setContent(List content){ /SnynZ.q
this.content = content; /h/6&R0l
} 1|o$X
J&A;#<qY
/** M-{*92y&
|
* @param page C@*%AY
* The page to set. ` *>V6B3
*/ 7SBM^r}
publicvoid setPage(Page page){ /nc~T3j
this.page = page; {*N^C@
} .4wTjbO6
} Qm
$(
-u6}T!
o:_^gJ+|
G7
1U 7
92!JKZe
2. 编写业务逻辑接口,并实现它(UserManager, .2e1S{ 9
#MUiL=
UserManagerImpl) ]\OWZ{T'j
java代码: W@l+ciZ_
3@&bxYXm
;SfNKu
/*Created on 2005-7-15*/ U);OR
package com.adt.service; GP* +
BEln6zj
import net.sf.hibernate.HibernateException; +W6Hva.
R4V \B
import org.flyware.util.page.Page; Ejq=*UOP
IeVLn^?+:
import com.adt.bo.Result; Yrpxy.1=F5
!(Q l)C
/** u,fA!
* @author Joa R8tF/dx>7
*/ qh-[L
publicinterface UserManager { 9SY(EL
R aefj(^V
public Result listUser(Page page)throws F+Z2U/'a
N=#4L$@-
HibernateException; e$/&M*0\f
*wwhZe4V
} &eIGF1ws
,<sm,!^<r
ob'n{T+lZ
1i
u =Y
+vz`go
java代码: ~n6[$WjZA
k5@d! }#c
2Pp&d>E4
/*Created on 2005-7-15*/ ]NtSu%u
package com.adt.service.impl; ?vu_k 'io
.|uLt J
import java.util.List; a=+T95ulDy
_R7 w?!t8
import net.sf.hibernate.HibernateException; noC?k }M
=OYQM<q
import org.flyware.util.page.Page; VFO\4:.
import org.flyware.util.page.PageUtil; Wr>(#*r7q
fYBH)E
import com.adt.bo.Result; m"Qq{p|'
import com.adt.dao.UserDAO; &x0C4Kh
import com.adt.exception.ObjectNotFoundException; 3sFeP&
import com.adt.service.UserManager; u g\w\b
BDe]18X
/** {B0h+. C
* @author Joa B,_`btJh
*/ W&(f&{A
publicclass UserManagerImpl implements UserManager { :[sOKV i
i"HgvBHx
private UserDAO userDAO; ~O:
U|&
m&IsDAn
/** s-k_d<
* @param userDAO The userDAO to set. F>+2DlA`<e
*/ NP/>H9Q2%
publicvoid setUserDAO(UserDAO userDAO){ 3bs4mCq
this.userDAO = userDAO; \DA$6w\\
} !gH9 ay
hazq#J!
/* (non-Javadoc) 6:?rlh
* @see com.adt.service.UserManager#listUser 8$vK5Dnn8
'<@=vGsye
(org.flyware.util.page.Page) }B q^3?,#{
*/ ^bUxLa[.
public Result listUser(Page page)throws :?CQuEv-
;GsQR+en
HibernateException, ObjectNotFoundException { YQgNv` l}
int totalRecords = userDAO.getUserCount(); lj2=._@R
if(totalRecords == 0) Q_zr\RM>
throw new ObjectNotFoundException GBP-V66
'r+PH*Mr
("userNotExist"); EO)%UrWnC
page = PageUtil.createPage(page, totalRecords); _+w/
pS`M
List users = userDAO.getUserByPage(page); 0^~\COa
returnnew Result(page, users); nl1-kB)$e|
} (j&A",^^S
!gP0ndRJ=
} vR>o}%`
$-vo}k%M
u&]vd /
o a<q /
4MW ]EQ-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 |(% u}V?
lKV"Mh+6
询,接下来编写UserDAO的代码: *'ZN:5%H
3. UserDAO 和 UserDAOImpl: .q;ED`G
java代码: Kt/)pc
zAScRg$:?
SEF6B45}1
/*Created on 2005-7-15*/ Bjj<\8^M
package com.adt.dao; F#V q#|_)>
Lz4ehWntO
import java.util.List; GAEO$e:
Hs0pW5oZ
import org.flyware.util.page.Page; ?tYpc_p#
{3edTu
import net.sf.hibernate.HibernateException; 4]XI"-M^D
B|o%_:]+E
/** '2^
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* @author Joa
Xm_$
dZ
*/ :tGYs8UK
publicinterface UserDAO extends BaseDAO { Y2T$BJJ
;+Yi.Q/\
publicList getUserByName(String name)throws LSd*|3E}n
wu~hqd
HibernateException; O`W%Tr
n:#TOU1ix<
publicint getUserCount()throws HibernateException; 83iCL; GS=
Vk}49O<K/
publicList getUserByPage(Page page)throws /c-nE3+rn
>Da~Q WW|
HibernateException; ]/dVRkZeAE
{aj/HFLNY
} 8^yJqAXK
$Ua56Y
"mIgs9l$
#hxyOq,
d'HOpJE
java代码: }ot"Sx\.
Q/^A #l[
L-h$Z0]_F
/*Created on 2005-7-15*/ -- k:a$Nt
package com.adt.dao.impl; <'m6^]:
[aW =
import java.util.List; 2qj{n+
6m`{Z`c$
import org.flyware.util.page.Page; WS0JS'
T] | d5E
import net.sf.hibernate.HibernateException; \2!!L=&4G
import net.sf.hibernate.Query; k DsIp=
i g71/'D
import com.adt.dao.UserDAO; I4e+$bU3
UH3t(o7O
/** 8b&uU [
* @author Joa %%}A|,
*/ 4E3g,%9u
public class UserDAOImpl extends BaseDAOHibernateImpl k`YYZt]@
XB\zkf_}Xc
implements UserDAO { Ill[]O
;u-4KK
/* (non-Javadoc) i^2IW&+}e}
* @see com.adt.dao.UserDAO#getUserByName tL(B pL'
z'MS#6|}
(java.lang.String) W{Q)-y
*/ P%>?[9!Nt
publicList getUserByName(String name)throws QZYU0;
VF
Fr:5$,At7-
HibernateException { 4<v;1
String querySentence = "FROM user in class ?p^2Z6J'$
N}Vn;29
com.adt.po.User WHERE user.name=:name"; - r#K#v3
Query query = getSession().createQuery q-AN[_@
;#QhQx
(querySentence); 3N4.$#>#9@
query.setParameter("name", name); * gqSWQ
return query.list(); 0|Ucd
} i/qTFQst
_
a(x?fa[D
/* (non-Javadoc) FC>d_=V
* @see com.adt.dao.UserDAO#getUserCount() ^Kq|ID
AP
*/ 49h0^;xlo:
publicint getUserCount()throws HibernateException { IgX4.]W5
int count = 0; ")`S0n5e
String querySentence = "SELECT count(*) FROM ;VzMU ;j
])T/sO#'
user in class com.adt.po.User"; ]0~qi@
Query query = getSession().createQuery S+I^!gT
{B{i(6C(
(querySentence); ycpE=fso'
count = ((Integer)query.iterate().next G$=-,6kZO
P_Uutn~
()).intValue(); nX[;^v/
return count; Rlw3!]5+2
} &Ocu#Cb
]Yz'8uts
/* (non-Javadoc) BQNp$]5s
* @see com.adt.dao.UserDAO#getUserByPage .Ff_s
H5M#q6`H6
(org.flyware.util.page.Page) 6
=>G#
*/ ^.HWkS`e
publicList getUserByPage(Page page)throws YoSQN/Z
(F&YdWe:
HibernateException { nQLs<]h1
String querySentence = "FROM user in class |uUuFm
|]ucHV
com.adt.po.User"; _s>^?x}
Query query = getSession().createQuery kk_zVrQ<
F`&>NQb
(querySentence); -9&g[
query.setFirstResult(page.getBeginIndex()) kL;t8{n
.setMaxResults(page.getEveryPage()); 14l; *
return query.list(); pxplWP,
} YFvgz.>QE
n;OHH{E{
} e,Zv]Cym
fPz=KoN
+by|
[.3sE
x[Q&k[xV
至此,一个完整的分页程序完成。前台的只需要调用 {B^pnLc
JQT4N[rEE
userManager.listUser(page)即可得到一个Page对象和结果集对象 3B#!2|
}td6fj_{
的综合体,而传入的参数page对象则可以由前台传入,如果用 d*9j77C ]
i./Y w
webwork,甚至可以直接在配置文件中指定。 3yMt1 fy
rWe
8D/oc
下面给出一个webwork调用示例: l $ Zs~@N
java代码: jt%WPkY:
h/=-tr
\e0x,2
/*Created on 2005-6-17*/ R=86w_
package com.adt.action.user; qKs7WBRJy
OR~G Ov|
import java.util.List; g&
>mP?
9OZ>y0)K~
import org.apache.commons.logging.Log; ?,V;f2c
import org.apache.commons.logging.LogFactory; ._(z~3s
import org.flyware.util.page.Page; ZjavD^ky
x`3.Wu\
import com.adt.bo.Result; ULrbQ}"cva
import com.adt.service.UserService; ,s81rJ-
import com.opensymphony.xwork.Action; ds')PIj
yh$ ~*UV
/** FJlsWh4,6=
* @author Joa c0hdLl;5
*/ qIk
)'!Vk
publicclass ListUser implementsAction{ T/Ez*iQW
dr>]+H=3E
privatestaticfinal Log logger = LogFactory.getLog ^CX,nj_(
wEv*1y4
(ListUser.class); r3?5'S`
5I_hh?N4Z
private UserService userService; rcW#6VZ=
<WgG=Kf)N
private Page page; 3XBp6`
uRs9}dzv
privateList users; ZS|Z98
+*Q9.LjV
/* X.:_"+I;
* (non-Javadoc) xQZMCd
* t2m ^
* @see com.opensymphony.xwork.Action#execute() YU*46 hA1B
*/ }v,W-gA
publicString execute()throwsException{ }%
FDm@+
Result result = userService.listUser(page); Q=MCMe
page = result.getPage(); R|6RI}
users = result.getContent(); Sk!v,gx
return SUCCESS; (#CBq
} +}`p"<'u
GF9ZL
/** M55e=
* @return Returns the page. H,/~=d:
^
*/ @m }rQT
public Page getPage(){ o&*1U"6D
return page; +D6-m
} Y^T-A}?`
!#l0@3
/** vK[v
eFH
* @return Returns the users. g%Th_= qy
*/ =]2
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publicList getUsers(){ 4UkP:Vz:
return users; N}eU.#L
} ~x76{.gT
,S7~=S
/** DtI%-I.
* @param page 8HHgN`_
* The page to set. KzxW?Ji$S
*/ (UbR%A|v;
publicvoid setPage(Page page){ z{7,.S
u
this.page = page; 9}? 5p]%
} oxxE'cx{g
L|dab{9
/** R.^Bxi-UG:
* @param users !nZI? z ;
* The users to set. h7Shl<f
*/ h$:&1jVY{
publicvoid setUsers(List users){ <S:,`v&Z
this.users = users; '_Hb}'sFI
} =rs=8Ty?S
P:bVcta9g
/** +dPE!:
* @param userService >=]NO'?O
* The userService to set. Vj9`[1}1Z
*/ KU8Cl>5
publicvoid setUserService(UserService userService){
HfZ (U5~
this.userService = userService; [hvig$L
} 1.ugXD
} U)T/.L{0i
\?p9qR;"4
x1 R!
q]wn:%rX
! X#3w-K
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ijR*5#5h
Is#v6:#^
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 iNaC ZC
A~%g"
么只需要: 0B!mEg
java代码:
^.><t+tM
P(W\aLp
V< 9em7
<?xml version="1.0"?> FB^dp}
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 6:7:NI l:
_4x[}e7KF
1.0//EN" "http://www.opensymphony.com/xwork/xwork- B@~eBU,$
h<z/LL8|
1.0.dtd"> El8.D3
II f >z_m
<xwork> d$G%F $BTs
XxrO:$
<package name="user" extends="webwork- HS|g
lhvZ*[[<)
interceptors"> D9pxe qf+=
"e!$=;5
<!-- The default interceptor stack name c )P%O
)jQe K
--> /%@RO^P
<default-interceptor-ref 8Jly!=Qm5
iLQt9Hyk
name="myDefaultWebStack"/> ]ge^J3az$u
:."n@sA@
<action name="listUser" (? #U&
'\vmfp=
class="com.adt.action.user.ListUser"> &>^Ympr
<param g he=mQ-
B0?@k
name="page.everyPage">10</param> !j\&BAxTEk
<result 9!/1F !
=v#A&IPA'
name="success">/user/user_list.jsp</result> 0 6v5/Xf
</action> d=u%"36y
a(t<eN>b!
</package> Jhq5G"
fw~%^*
</xwork> TKs@?Q,J
?ia[KLt"
9g,L1 W*
q,h.W JI
p 7E{es|J
LYo7?rp
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 .Y Frb+6
,%DAh
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。 ~$&r(9P
/01(9(
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 $ax%K?MBD
eOnl
sx/
+OuG!3+w
yDBgSO{d
[tw<TV"\
我写的一个用于分页的类,用了泛型了,hoho Ku,A}5-6
Tqh Rs
java代码: vT<wd#
?fX8WRdh
vM;dPE7
package com.intokr.util; K OHH74}_
H
{Wpf9_
K
import java.util.List; Kpbber
cO?"
/** 7^e}|l
* 用于分页的类<br> 5|={1Lp24g
* 可以用于传递查询的结果也可以用于传送查询的参数<br> }K]VlFR
* G:s:NXy^
* @version 0.01 yXQ;LQ;
* @author cheng u5|e9(J
*/ 'r <BaL
public class Paginator<E> { o5A_j?t
privateint count = 0; // 总记录数 v-aq".XQ
privateint p = 1; // 页编号 .
zMM86 c
privateint num = 20; // 每页的记录数 :iC\#i]6
privateList<E> results = null; // 结果 8$olP:d
P9chRy
/** hWe}(Ks
* 结果总数 L2A#OZZu
*/ h>Pg:*N,(
publicint getCount(){ f__WnW5h
return count; 'GoeVq
} K1WoIv<Ym
Q]:%Jj2
publicvoid setCount(int count){ \<>%_y'/)h
this.count = count; 0'}?3/u-
} p&27|1pZm
1g.9R@Kc$
/** Wm&f+{LO+K
* 本结果所在的页码,从1开始 \+A<s,x
* U.0/r!po
* @return Returns the pageNo. PTZ1oD
*/ ]997`,1b
publicint getP(){ rq?x]`u
return p; a][Z;g
} >Tx;<G
tAi9mm;k
/** b(Xg6
* if(p<=0) p=1 3?(p;
* $8}'6,
* @param p jU~%5R
*/ +yI^<BH
publicvoid setP(int p){ F'*&-l
if(p <= 0) 0GVok$r@
p = 1; OwaXG/z~
this.p = p; "c*|vE
} g7F
Z -
l[| e3<H
/** v a;wQ~&
* 每页记录数量 m m`3-F|
*/ s30_lddD
publicint getNum(){ Q(3x"+
return num; 'a*IZb-M
} k 'b|#c9c
,oe{@z{*@
/** 0^z$COCv
* if(num<1) num=1 PBv43uIL
*/ W'$~mK\
publicvoid setNum(int num){ e{:qW'%
if(num < 1) [\yI<^_a
num = 1; |L&V-f&K
this.num = num; 2ZeL
} Hyg?as>}u
')V5hKb^
/** E>D@#I>
* 获得总页数 vGw}e&YI
*/ @~ L.m}GF
publicint getPageNum(){ s_TM!LRUcw
return(count - 1) / num + 1; k5YDqGn'q
} |93%,
ENzeVtw0
/** NU[{oI<a
* 获得本页的开始编号,为 (p-1)*num+1 Z}wAh|N-
*/ ~/%){t/uLY
publicint getStart(){ K~>kruO";
return(p - 1) * num + 1; H<yec"
} W|
p?KJk)
[PT_y3'%
/** _HQa3wj
* @return Returns the results. }2@$2YR[
*/ V2.K*CpZ7
publicList<E> getResults(){ 4E)[<%
return results; 9[*kpMC
} b4wJnmC8
G`z48
public void setResults(List<E> results){ /MC\!,K
this.results = results; 'Bx7b(xqk
} q.7CPm+
AUK7a
public String toString(){ : Ej IV]e
StringBuilder buff = new StringBuilder ,3j*D+
n_<]9
(); /Kvb$]F+!
buff.append("{"); pK`rm"6G
buff.append("count:").append(count); JoYzC8/r
buff.append(",p:").append(p); {IVqV6:
buff.append(",nump:").append(num); gyK"#-/_d
buff.append(",results:").append '9)@ U+yfQ
u@HP@>V
(results); w <ID<
buff.append("}"); UgP5^3F2
return buff.toString(); CHz(wn
} C*9m `xh
cg~FW2Q
} ]V_9[=%
]~P?
zM!*r~*k$