Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 xMAb=87_
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 p3YF
+|=5zWI/
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};$>47m
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 3Ta<7tEM
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。 x6 c#[:R&
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分页支持类: bn$}U.m$-
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java代码: )QvuoaJQ
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package com.javaeye.common.util; -=A W. Zo
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import java.util.List; r\-25F<e5
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publicclass PaginationSupport { o-D,K dY
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publicfinalstaticint PAGESIZE = 30; 96.z\[0VZ
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privateint pageSize = PAGESIZE; EdPN=
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privateList items; l^IPN'O@
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privateint totalCount; .u_k?.8|
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privateint[] indexes = newint[0]; $.z~bmH"D
|= frsf~?
privateint startIndex = 0; IHg)xZ
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public PaginationSupport(List items, int epH48 )2
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totalCount){ <}E^r_NvD
setPageSize(PAGESIZE); |
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setTotalCount(totalCount); B9Dh^9?L
setItems(items); Qn7l-:`?
setStartIndex(0); q-.e9eoc\
} `FImi9%F
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public PaginationSupport(List items, int #&1Y!kbdd
@HfWAFT
totalCount, int startIndex){ ?[W(r$IaE
setPageSize(PAGESIZE); bw7!MAXd
setTotalCount(totalCount); i;0`d0^
setItems(items); {I|k@
setStartIndex(startIndex); 6[9E^{(z
} '^l/e: (H3
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public PaginationSupport(List items, int 1>*]jj}
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totalCount, int pageSize, int startIndex){ V=|^r?
setPageSize(pageSize); lO9{S=N
setTotalCount(totalCount); ED/-,>[f
setItems(items); T^a {#B
setStartIndex(startIndex); F.=uJdl.!
} JXeqVKF
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publicList getItems(){ Et'C4od s
return items; (Df<QC`0v
} |Z;wk&
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publicvoid setItems(List items){ {I 7pk6Qd
this.items = items; xgR* j
} T , =ga
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publicint getPageSize(){ y`Pp"!P"O
return pageSize; BHmA*3?
} tL+8nTL
A2&&iL=j/
publicvoid setPageSize(int pageSize){ "tIf$z
this.pageSize = pageSize; |->y'V
}
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publicint getTotalCount(){ +lha^){
return totalCount; A?}OOjA
} ;D8Nya>%
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publicvoid setTotalCount(int totalCount){ \Di~DN1
if(totalCount > 0){ ]bnxOk
this.totalCount = totalCount; jX&&@zMq
int count = totalCount / *vAOUqX`x
2K*-uT#$~
pageSize; lIjHd#q-C
if(totalCount % pageSize > 0) 1]>KuXd
r
count++; Br~%S?4"o
indexes = newint[count]; >qF KXzI
for(int i = 0; i < count; i++){ V2FE|+R%g
indexes = pageSize * x#8=drh.:C
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i; r3j8[&B"
} Zc4hjg
}else{ "}HQ)54&
this.totalCount = 0; _Mt:^H}Sy
} )ql?}
} #6H<JB
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publicint[] getIndexes(){ |16
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return indexes; \[oHt:$do
} C]=E$^|{
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publicvoid setIndexes(int[] indexes){ 78QFaN$
this.indexes = indexes; l wg.'<
} x b0+4w|
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publicint getStartIndex(){ b/K&8C,c
return startIndex; ?*s!&-KI
} _@OYC<
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publicvoid setStartIndex(int startIndex){ fcZOsTj
if(totalCount <= 0) `p ?E{k.N
this.startIndex = 0; t!u*6W|@
elseif(startIndex >= totalCount) S-/#3
this.startIndex = indexes blN1Q%m6
Y+j KP*ri
[indexes.length - 1]; -mkync3
elseif(startIndex < 0) 8_,ZJ9l;
this.startIndex = 0; ;:e,C@Fm
else{ ;&!dD6N
this.startIndex = indexes }1W$9\%
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[startIndex / pageSize]; 3
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} XGoy#h
} I coL/7k3
8
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publicint getNextIndex(){ H\k5B_3OU
int nextIndex = getStartIndex() + Ax^'unfQ:
\Cs<'(=
pageSize; 2bJFlxEU
if(nextIndex >= totalCount) `@eH4}L*
return getStartIndex(); fA8+SaXW%
else Fq9[:
return nextIndex; 3-R3Qlr
} 709eLhXrH
7asq]Y}<
publicint getPreviousIndex(){ :z\f.+MI
int previousIndex = getStartIndex() - #~x5}8
VL{#.;QQa
pageSize; f$>orVm%.
if(previousIndex < 0) eFio,
return0; t4IJ%#22
else i4I0oRp
return previousIndex; Y2X1!Em>B
} K*Jtyy}r
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} 2f!oA~|2
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抽象业务类 V)2_T!e%*
java代码: W\,lII0
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/** 9>R|k$`
* Created on 2005-7-12 V@S/!h+
*/ 8q3TeMYV
package com.javaeye.common.business; Fw9``{4w
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import java.io.Serializable; @(c<av?
import java.util.List; V@:=}*E
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import org.hibernate.Criteria; JJ?ri,
import org.hibernate.HibernateException; 8 uxFXQ
import org.hibernate.Session; 5{q/z^]
import org.hibernate.criterion.DetachedCriteria; ]7t\%_
import org.hibernate.criterion.Projections; z4641q5'm
import uAs*{:4n
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org.springframework.orm.hibernate3.HibernateCallback; Q)BoWd
import va(9{AXI
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org.springframework.orm.hibernate3.support.HibernateDaoS A9UaLSe
8MeXVhM
upport; T(UYlLe
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import com.javaeye.common.util.PaginationSupport; a<'$` z|s
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public abstract class AbstractManager extends ^Cn]+0G#C8
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HibernateDaoSupport { kQd[E-b7
hS{
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privateboolean cacheQueries = false; +Z&&H'xD
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privateString queryCacheRegion; = )l: ^+q
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publicvoid setCacheQueries(boolean $a*Q).^
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cacheQueries){ D2:a
this.cacheQueries = cacheQueries; 0aTbzOn&
} Cn;H@!8<s
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publicvoid setQueryCacheRegion(String uAS8F=9xP
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queryCacheRegion){ z!C4>,
this.queryCacheRegion = /Np"J
*DCNu{6
queryCacheRegion; a]Da`$T
} s.`%ZDl@Y
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publicvoid save(finalObject entity){ ^$+f3Z'
getHibernateTemplate().save(entity); ~q?"w:@;x
} AzO3 (1:
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publicvoid persist(finalObject entity){ Hv gK_'
getHibernateTemplate().save(entity); BdB`
} Hrg=sR
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publicvoid update(finalObject entity){ },EUcVXk
getHibernateTemplate().update(entity); v(@+6#&
} E}b>7L&w
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publicvoid delete(finalObject entity){ Z>Kcz^a#
getHibernateTemplate().delete(entity); Z_V&IQo-7
} w[YkTv
v`+n`DT
publicObject load(finalClass entity, _2gT1B
jU4)zN/`r
finalSerializable id){ Q$.V:#
return getHibernateTemplate().load GkGC4*n
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(entity, id); ( ln
} Pvg
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publicObject get(finalClass entity, 3
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finalSerializable id){ ttbQergS
return getHibernateTemplate().get ^{fi^lL=
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(entity, id); 7<QYT+6xV
} {b-0_
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publicList findAll(finalClass entity){ {*<O"|v
return getHibernateTemplate().find("from @q{:Oc^
_!C)r*0(
" + entity.getName()); lNA'M&
} `hK>bHj
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publicList findByNamedQuery(finalString !4 4mT'Y
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namedQuery){ RP`GG+K
return getHibernateTemplate p-Rm,xyL%
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().findByNamedQuery(namedQuery); liugaRO8J
} gc,J2B]61
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publicList findByNamedQuery(finalString query, 5Aa31"43n
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finalObject parameter){ *3.yumcv{L
return getHibernateTemplate I!F}`d
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().findByNamedQuery(query, parameter); A"\P&kqMV
} f 74%YY
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publicList findByNamedQuery(finalString query, qL%.5OCn(
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finalObject[] parameters){ !!-}ttFA
return getHibernateTemplate h7de9Rt
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().findByNamedQuery(query, parameters); aeuf, #
} VW{aUgajO
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publicList find(finalString query){ Qr|N)
return getHibernateTemplate().find ^Hz
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(query); @O}IrC!bf
} G!!-+n<
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publicList find(finalString query, finalObject *2 qh3
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parameter){ SZim>@R
return getHibernateTemplate().find ||{T5E-.F
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(query, parameter); eD*?q7
} w|!YoMk+o
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public PaginationSupport findPageByCriteria LPq*ZZK
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(final DetachedCriteria detachedCriteria){ ou<S)_|Iu
return findPageByCriteria A0cM(w{7_
6)=](VmNL`
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ij;==f~G
} 90
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public PaginationSupport findPageByCriteria 8 *4@-3Sx
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(final DetachedCriteria detachedCriteria, finalint c&E*KfOG
+Od1)_'\D3
startIndex){ ~pHJ0g:t
return findPageByCriteria )LkM,T
l?3vNa FeR
(detachedCriteria, PaginationSupport.PAGESIZE, %/{IssCR7
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startIndex); !7A"vTs
} 6@"Vqm|HD
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public PaginationSupport findPageByCriteria *0=fT}&!
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(final DetachedCriteria detachedCriteria, finalint XHWh'G9
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pageSize, l\K%
finalint startIndex){ n?y'c^
return(PaginationSupport) BhqhyX\D&y
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getHibernateTemplate().execute(new HibernateCallback(){ >pgQb9
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publicObject doInHibernate 8# 6\+R
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(Session session)throws HibernateException { _L$)2sl1R
Criteria criteria = 2~vo+ng
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detachedCriteria.getExecutableCriteria(session); i?ZA x4D
int totalCount = fp9rO}##
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((Integer) criteria.setProjection(Projections.rowCount aML#Z |n
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()).uniqueResult()).intValue(); &foD&
criteria.setProjection A ?#]s
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(null); P;j&kuW|zL
List items = 0LS-i% 0
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criteria.setFirstResult(startIndex).setMaxResults YkSuwx@5_q
)V=0IZi
(pageSize).list(); 1#/6r :
PaginationSupport ps = \^Ep>Pq`]
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new PaginationSupport(items, totalCount, pageSize, 4S'[\ZJO
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startIndex); JRD8Lz]Q3
return ps; iOl%-Y
} F|,6N/;!W
}, true); |pBMrN+is
} h5x*NM1Ih
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public List findAllByCriteria(final wjL|Z8
w
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DetachedCriteria detachedCriteria){ S)+CTVVE
return(List) getHibernateTemplate itw{;j
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().execute(new HibernateCallback(){ wcwQj Hwd
publicObject doInHibernate ` ovgWv
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(Session session)throws HibernateException { 10?qjjb&
Criteria criteria = #^Ys{
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detachedCriteria.getExecutableCriteria(session); o/WC@!wg K
return criteria.list(); /oFc03d
} r?\|f:M3
}, true); k5wi'
} -xz|ayn
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public int getCountByCriteria(final _AprkI_
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DetachedCriteria detachedCriteria){ wrabyRjK
Integer count = (Integer) Nl
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getHibernateTemplate().execute(new HibernateCallback(){ Q{[@`bZB
publicObject doInHibernate N};t<Xev
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(Session session)throws HibernateException { )%qtE34`
Criteria criteria = *
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detachedCriteria.getExecutableCriteria(session); gJh}CrU-
return i|S:s
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criteria.setProjection(Projections.rowCount 9KyZEH;pY
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()).uniqueResult(); +}U2@03I
} =e{.yggE
}, true); MxTmWsaW
return count.intValue(); q? 9GrwL8F
} @(>XOj?+
} g_vm&~U/'
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用户在web层构造查询条件detachedCriteria,和可选的 `|EH[W&y
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 r|fO7PD
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PaginationSupport的实例ps。 OJpj}R
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ps.getItems()得到已分页好的结果集 J{tVa(.
ps.getIndexes()得到分页索引的数组 7Cy<mS
ps.getTotalCount()得到总结果数 \[ M_\&GC
ps.getStartIndex()当前分页索引 5g>wV
ps.getNextIndex()下一页索引 _mk5^u/u
ps.getPreviousIndex()上一页索引 jct./arK
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R ]P;sk5
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~5 >[`)
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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 X;!~<~@Y
]JMl|e
一下代码重构了。 B+"g2Y
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我把原本我的做法也提供出来供大家讨论吧: V LdB_r3lQ
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首先,为了实现分页查询,我封装了一个Page类: @Y-TOCadT
java代码: Gx'TkU=
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/*Created on 2005-4-14*/ }l;Lxb2`
package org.flyware.util.page; jO8k6<l
x_!ZycEa
/** 5<+KR.W
* @author Joa H?Jm'\~
* CDdkoajBa
*/ f$F*3
publicclass Page { fdv`7u+}a
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/** imply if the page has previous page */ ][7p+IsB
privateboolean hasPrePage; Z
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/** imply if the page has next page */ GwLFL.Ke
privateboolean hasNextPage; ]KuMz p!
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/** the number of every page */ DtF}QvA
privateint everyPage; Uyx&E?SlEq
n]N 96oD
/** the total page number */ YnTB&GPxl
privateint totalPage; 9[Qd)%MO
)/|6'L-2
/** the number of current page */ F
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privateint currentPage; lA;a
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/** the begin index of the records by the current M+xdHBg
jH*)%n5,\
query */ Qa`hR
privateint beginIndex; -<f;l_(
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/** The default constructor */ 0 f/.>1M=
public Page(){ ]axh*J3`i
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} q/gB<p9
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/** construct the page by everyPage aT!;{+
* @param everyPage {nMAm/kyj
* */ |qN'P}L
public Page(int everyPage){ '0t-]NAc
this.everyPage = everyPage; %[QV,fD'E
} }e]f
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/** The whole constructor */ O'DW5hBL0
public Page(boolean hasPrePage, boolean hasNextPage, lU2c_4
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int everyPage, int totalPage, }5 9U}@xC
int currentPage, int beginIndex){ , c;eN
this.hasPrePage = hasPrePage; g:#dl\k
this.hasNextPage = hasNextPage; rOfK~g,X
this.everyPage = everyPage; e}{U7xQm1
this.totalPage = totalPage; #D%ygh=
this.currentPage = currentPage; 1|QvN1?
this.beginIndex = beginIndex; ,^'R_efY
} k(s;,B\
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/** j 6)Y
* @return e [0w5)X
* Returns the beginIndex. nCxAQ|P?
*/ "$^0%-
publicint getBeginIndex(){ }
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return beginIndex; " Ar*QJ0]
} !K0JV|-?t
n(;:*<Rh
/** i+vsp@d
* @param beginIndex $#NQ<3
* The beginIndex to set. 3Rv7Qx
*/ @xWdO,#
publicvoid setBeginIndex(int beginIndex){ 40P) 4w
this.beginIndex = beginIndex; aP()|js
} w!3>N"em
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/** +Ov2`O8?
* @return :`,3h%
* Returns the currentPage. ${&5]!E[>D
*/ m:CTPzAt
publicint getCurrentPage(){ +|RB0}hFS-
return currentPage; 3{Q,hpZN
} lhLGG
7v"lNP-?jU
/** O>0VTW
* @param currentPage `)>7)={
* The currentPage to set. :
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*/ Zm TDQ`Ix
publicvoid setCurrentPage(int currentPage){ ^y_fRP~
this.currentPage = currentPage; %@J1]E;
} 6L4$vJ
$p* p
/** #;tT8[Ewuw
* @return HeN~c<NuB
* Returns the everyPage. )LHj+B
*/ h8 @
publicint getEveryPage(){ L\aBc}
return everyPage;
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} \c`oy=qY0
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/** p9ZXbAJ{
* @param everyPage \+PIe7f_
* The everyPage to set. akuJz
*/ F@<0s&)1
publicvoid setEveryPage(int everyPage){ GUB`|is^
this.everyPage = everyPage; u' Qd,
} *JCQu0
hP@(6X,"
/** #VbVsl
* @return c9Es%@]
* Returns the hasNextPage. }E^S]hdvz
*/ Wa"(m*hW
publicboolean getHasNextPage(){ vP-M,4c
return hasNextPage; 6vzk\n
} Z'v-F^
l95<QI
/** `m~syKz4A
* @param hasNextPage e_3CSx8Cc
* The hasNextPage to set. x2VBm$>
*/ 4jmK].
publicvoid setHasNextPage(boolean hasNextPage){ 3yS
this.hasNextPage = hasNextPage; xBnbF[
} (zo^Nn9VJ
'C+;r?1!h
/** Yn51U6_S
* @return &%aXR A#+
* Returns the hasPrePage. "E!mva*NU
*/ V1=*z
publicboolean getHasPrePage(){ vFmJ;J
return hasPrePage; vxlOh.a|/L
} wzcai
0y*
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z
/** $\Lyi#<
* @param hasPrePage LX+5|u
* The hasPrePage to set. |VH!)vD
*/ Xo5$X7m
publicvoid setHasPrePage(boolean hasPrePage){ tOdT[&
this.hasPrePage = hasPrePage; 0&Gl@4oZ"
} NY
_uxPx 21g}
/** ]5CNk+`'
* @return Returns the totalPage. #G^A-yjn
* !4#"!Md4o
*/ <_S@6?
publicint getTotalPage(){ IfdI|ya
return totalPage; 7G2PMe;$m
} m$Y
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8}p8r|d!ls
/** _cqy`p@"
* @param totalPage Q%ad q-B
* The totalPage to set. .=RlOK
*/ w; TkkDH
publicvoid setTotalPage(int totalPage){ o3Ot.9L
this.totalPage = totalPage; (yrh=6=z
} |WQ9a' '
%n?vJ#aX%
} !|{IVm/J
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/="HqBI#i
7_jE[10
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 I+?hG6NM
3!9Z=-tD
个PageUtil,负责对Page对象进行构造: S\C*iGeqJ
java代码: Un=a
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I2Ev~!
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/*Created on 2005-4-14*/ sRRI3y@
package org.flyware.util.page; %CH6lY=lI
~5aE2w0K
import org.apache.commons.logging.Log; -AD2I {C
import org.apache.commons.logging.LogFactory; fv'4f$U
W:s@L#-
/** {ISE'GJj
* @author Joa gSi5u#}J
* I}0_nge
*/ 4iX-( ir,
publicclass PageUtil { +&v\
/
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privatestaticfinal Log logger = LogFactory.getLog 'imU`zeo
khX|"d360
(PageUtil.class); 1=GI&f2I
#gZ|T
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/** ~1 ZD[@
* Use the origin page to create a new page r|Zi3+
* @param page 5G*II_j
* @param totalRecords 5~VosUpe7
* @return a5c'V
*/ RI.2F*|
publicstatic Page createPage(Page page, int
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totalRecords){ :=. *I
return createPage(page.getEveryPage(), KFhG (
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page.getCurrentPage(), totalRecords); g`Md80*Zfk
} x7ATI[b[
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/** <0j{ $.
* the basic page utils not including exception szq+@2:
@6MAX"
handler !D:k!
* @param everyPage gY5l.&
* @param currentPage X0i3 _RVa
* @param totalRecords c ~Kc7}I
* @return page $G";2(-k
*/ 8F6h#%9
publicstatic Page createPage(int everyPage, int G}Z4g
ZgYZwc&-
currentPage, int totalRecords){ $$gtZ{ukQ
everyPage = getEveryPage(everyPage); Mtp%co )f
currentPage = getCurrentPage(currentPage); &YX6"S_B
int beginIndex = getBeginIndex(everyPage, Jt=>-Spj
19I:%$U3
currentPage); TVkcDS
int totalPage = getTotalPage(everyPage, Yn<)k_kp
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totalRecords); /H&aMk}J@y
boolean hasNextPage = hasNextPage(currentPage, G11cNr>*
i^/54
totalPage); Vyt
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boolean hasPrePage = hasPrePage(currentPage); 2%YXc|gGT
L8P36]>
returnnew Page(hasPrePage, hasNextPage, yYX :huw
everyPage, totalPage, Mq+<mX7
currentPage, _Ex?Xk
VO -784I
beginIndex); I~RcOiL)
} q$ >_WF#||
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privatestaticint getEveryPage(int everyPage){ ptR
return everyPage == 0 ? 10 : everyPage; .mt^m
} aL)$b
3^ ~Zj95M
privatestaticint getCurrentPage(int currentPage){ B$7[8h
return currentPage == 0 ? 1 : currentPage; u}CG>^0C
} @_O3&ZK
t|=n1\=?
privatestaticint getBeginIndex(int everyPage, int P#bm uCOS
y:9?P~
currentPage){ ZgBckb
return(currentPage - 1) * everyPage; <G9<"{
} RAOKZ~`
yk#rd~2Z0
privatestaticint getTotalPage(int everyPage, int }K;iJ~kD1
.f%vDBJS
totalRecords){ 6vWii)O.D
int totalPage = 0; .h6Y<
E
!qS05
if(totalRecords % everyPage == 0) )|:8zDuJ
totalPage = totalRecords / everyPage; `D"1
gD}{A
else "c EvFY
totalPage = totalRecords / everyPage + 1 ; PHQcstW
QRiF!D)Nk
return totalPage; v?{vg?vI
} Vy r]
x
ku-cn2M/
privatestaticboolean hasPrePage(int currentPage){ Crg#6k1~EN
return currentPage == 1 ? false : true; l3\9S#3-^
} CQjV!d0j
3l+|&q[v
privatestaticboolean hasNextPage(int currentPage, x' ?.~
1"d\mE
int totalPage){ w&9F>`VET
return currentPage == totalPage || totalPage == k3/4Bt G/
`43vxcMg
0 ? false : true; e00RT1L
} W=F3XYS
\Qp}|n1JY
VrudR#q
} (\tq<h0
,A^L=+
'&/(oJ;O~
~V!EtZG$
C\J@fpH(t`
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。 { .cB>L
Q.<giBh
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 rrbZ+*U
s^obJl3
做法如下: x}uwWfe 3
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %odw+PhO
:S#eg1y.w]
的信息,和一个结果集List: Q-:Ah:/
java代码: Bk@bN~B4
DCz\TwzU
IM$'J
/*Created on 2005-6-13*/ {6ajsy5=
package com.adt.bo; #3YdjU3w
T..-)kL+p
import java.util.List; <JG Yr 4V
n})
import org.flyware.util.page.Page; )x y9X0
(69kvA&|q
/** M_yZR^;^-
* @author Joa {c.}fyN
*/ 6ch@Be5*
publicclass Result { VOD1xWrb
% cU-5\xF
private Page page; 7'c8]/qh
Ty)gPh6O
private List content; no eb f
0m
qSA
/** jY1^+y{
* The default constructor (L]T*03#
*/ ~4l6unCI
public Result(){ >6n@\n
super(); fN~8L}!l
} Vx0MG{vG1
?U7&R%Lh`
/** n\~"Wim<b
* The constructor using fields }S
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* ag|9$
* @param page BF@m)w.v
* @param content F^4*|g
*/ KB$ vQ@N
public Result(Page page, List content){ ;""-[4C
this.page = page; =iA"; x
this.content = content; r9U[-CX:"
} <6~/sa4GN
`PXoJl
/** !.x=r
* @return Returns the content. G:H(IA7Z
*/ A0'tCq]?0
publicList getContent(){ JI28}Cxs0
return content; $u/8Rp
} QSlf=VK*y
p?EEox
/** _Eet2;9
* @return Returns the page. 9 ayH:;
*/ i[V,IP +
public Page getPage(){ LGdf_M-f
return page; w+:+r/!g
} ?,A8 fR
ulJ+:zwq$
/** *R1d4|/G
* @param content 5k!(#@a_T
* The content to set. 476M` gA
*/ @5uyUSt]
public void setContent(List content){ )[a?J,
this.content = content; -0[>}!l=G
} QZeb+r
oQE_?">w
/** |G5=>W
* @param page _ ;v_L
* The page to set. f]^ J,L9qz
*/ eFeCS{LV+
publicvoid setPage(Page page){ l% 3Q=c
this.page = page; [9# #Kb
} B@:XC&R^
} `jl. f
y[Fw>g1`q
$ET/0v"V
<{P^W;N7
Wl^/=I4p#
2. 编写业务逻辑接口,并实现它(UserManager, n,R[O_9u[
QyBK*uNdV
UserManagerImpl) D(2kb
java代码: =h1 QN
2T{-J!k
9fk\Ay1P
/*Created on 2005-7-15*/ U~QCN[gh
package com.adt.service; FkkZyCqZ`
uc{Qhw!;:
import net.sf.hibernate.HibernateException; [~&:`I1
1]zyME
import org.flyware.util.page.Page; g#bfY=C
bl QzVp-
import com.adt.bo.Result; jmwQc&
.>\>F{#~
/** 0V>N#P]
* @author Joa ztt%l #
*/ /m|&nl8"qe
publicinterface UserManager { [sh"?
-^NAHE$bW
public Result listUser(Page page)throws Tef3
Z6
clU3#8P!=
HibernateException; :j5 0]zLy{
r
z>zdj5}
} 1Tk\n
E* DVQ3~
A0 w `o
3qd-,qC
$9u
java代码: }sN9QgE
M`,Z#)Af
8f`b=r(a>
/*Created on 2005-7-15*/ .TrQ +k>
package com.adt.service.impl; DWevg;_]$(
mQ
`r`DW
import java.util.List; q@!H^hd}
=;?PVAdu%#
import net.sf.hibernate.HibernateException; GeW$lA I
i{x0#6_Y
import org.flyware.util.page.Page; )-:f;#xJ
import org.flyware.util.page.PageUtil; F/,<dNJ
3'NL1d u
import com.adt.bo.Result; 7bW!u*v-c
import com.adt.dao.UserDAO; >"My\o
import com.adt.exception.ObjectNotFoundException; vrEaNT$J-
import com.adt.service.UserManager; ReGb.pf
xbC-ueEj
/** |~vQ0D
* @author Joa u$ / ]59
*/ |@9I5Eg)iE
publicclass UserManagerImpl implements UserManager { .6A:t?.
Pj5#G0i%
private UserDAO userDAO; a/`Yh>ou
|ssIUJ
/** QZq9$;>dW
* @param userDAO The userDAO to set. ;77o%J'l
*/ ] ,aAzjZ
publicvoid setUserDAO(UserDAO userDAO){ uTt:/gm
this.userDAO = userDAO; 10C91/
} 0\<-R
aC6b})^
/* (non-Javadoc) zi&d
* @see com.adt.service.UserManager#listUser ;GEu.PdxB
h*LL(ow5
(org.flyware.util.page.Page) ]|BSX-V.%i
*/ -ZON']|<}k
public Result listUser(Page page)throws e*Med)tc^$
wef^o"aP
HibernateException, ObjectNotFoundException { NS~knR\&
int totalRecords = userDAO.getUserCount(); 9{#|sABGD
if(totalRecords == 0) 'i-O
throw new ObjectNotFoundException n\p\*wb
491I
("userNotExist"); YGmdiY:;1
page = PageUtil.createPage(page, totalRecords); Qg.:w
List users = userDAO.getUserByPage(page); +B|X
k[
returnnew Result(page, users); beR)8sC3q
} diL l>z
TRok4uc
} Z69IHA[
! HC<aWb
cb,sb^-
ng*E9Puu[
MW>28
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 vp9<.*h
dkp[?f)x
询,接下来编写UserDAO的代码: lM%fgyX
3. UserDAO 和 UserDAOImpl: sZDJ+
java代码: nv{4
U}&P
K! j*:{
:J-5Q]#
/*Created on 2005-7-15*/ *
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package com.adt.dao; u.FDe2|[)
A\.*+k/B
import java.util.List; _q4m7C<
= lD]sk
import org.flyware.util.page.Page; Z$XpoDbOy
a $%[!vF
import net.sf.hibernate.HibernateException; uy:=V}p
c`; LF'!
/** d~8~RT2m
* @author Joa
RZ%X1$
*/ :L0W"$
publicinterface UserDAO extends BaseDAO { -=IM8Dny
[1GEe
publicList getUserByName(String name)throws @NE#P&f
b\S}?{m5
HibernateException; W2N 7
D|:sSld @
publicint getUserCount()throws HibernateException; :/qO*&i,N
dhkpkt<G8
publicList getUserByPage(Page page)throws R*m"'|U
&Z!2xfQy>
HibernateException; Uk6!Sb
j56 An6g
} 7k|(5P;
w'XgW0j{
v{Vesf
,&G
M\FTeb
>t(@?*ZFT
java代码: $ :wM'&M
pnJT]?},
.?RjH6W
/*Created on 2005-7-15*/ @D=`iG%
package com.adt.dao.impl; x~eEaD5m%J
EZBzQ""
import java.util.List; ]E^f8s0#V
^mQfXfuL
import org.flyware.util.page.Page; yw!`1#3.
F\bI6gj
import net.sf.hibernate.HibernateException; A!yLwkc:5
import net.sf.hibernate.Query; F2'cL @E3
=)8fE*[s
import com.adt.dao.UserDAO; @x
+#ZD(
>~~\==".
/** Xs@ ^D,
* @author Joa =U2n"du
*/ )A=g# D#
public class UserDAOImpl extends BaseDAOHibernateImpl )n@ 3@NV
]5/U}Um
implements UserDAO { b%j:-^0V
vy2aNUmt
/* (non-Javadoc) =]"|x7'!
* @see com.adt.dao.UserDAO#getUserByName (=V[tI+Ngt
mC(t;{
(java.lang.String) !H\GHA'DO]
*/ Dj(7'jT
publicList getUserByName(String name)throws x`i`]6q
W=]",<
HibernateException { ,>v9 Y#U
String querySentence = "FROM user in class Qe.kNdT+_
Z]\^.x9S
com.adt.po.User WHERE user.name=:name"; >]8.xkQq
Query query = getSession().createQuery ;NeEgqW"
#)}bUNc'
(querySentence); S'p`ECfVMA
query.setParameter("name", name); $VIq)s2az|
return query.list(); w8I&:"^7<
} yt:V+qdv
l?_!eA
/* (non-Javadoc) ?I#hrv@
* @see com.adt.dao.UserDAO#getUserCount() [{LnE:
*/ HW Os@!cL
publicint getUserCount()throws HibernateException { pY#EXZ#
int count = 0; T<k1?h^7
String querySentence = "SELECT count(*) FROM G>>u#>0
UVUO}B@[S
user in class com.adt.po.User"; IF}c*uGj}
Query query = getSession().createQuery E9 q;>)}
w*}yw"gP*0
(querySentence); m@yVG|eP#
count = ((Integer)query.iterate().next [j U
N@a'd0oTd
()).intValue(); ?QT"sj64w
return count; u;qMo `-
} m>dcb
6B+g
C-^%g[#
/* (non-Javadoc) 7qK0!fk5
* @see com.adt.dao.UserDAO#getUserByPage EFt`<qwj
|
8Egw-f
(org.flyware.util.page.Page) m{dyVE
*/ mX.3R+t
publicList getUserByPage(Page page)throws Zbh]SF{3F
5po'(r|U
HibernateException { ]O=S2Q
String querySentence = "FROM user in class G,|]a#w&v.
2*wO5v
com.adt.po.User"; VSpt&19
Query query = getSession().createQuery f"<@6Axq
GKujDx+h
(querySentence); + >gbZ-S
query.setFirstResult(page.getBeginIndex()) AKCfoJ
.setMaxResults(page.getEveryPage()); mQ60@_"Y=,
return query.list(); eGe[sv"k
} Y!1^@;)^
I<(.i!-x
} K&IrTA
j}
) UDJ[pL@
ml33qXW:
y(3c{y@~X
Tb0;Mbr
至此,一个完整的分页程序完成。前台的只需要调用 ^A"lkV7
feI[M;7u
userManager.listUser(page)即可得到一个Page对象和结果集对象 L+~YCat|$U
j*La,iF
的综合体,而传入的参数page对象则可以由前台传入,如果用 "^
6lvZP(
[bi3%yWh
webwork,甚至可以直接在配置文件中指定。 ?%xhe
M o"JV
下面给出一个webwork调用示例: zdjM%l);
java代码: Q),3&4pM
_L4<^Etfm
i+X2M-[Ls
/*Created on 2005-6-17*/ UrhM)h?%
package com.adt.action.user; !&a;P,_Fb
}6CXJ+-UR
import java.util.List; Dz8:;$/
R7B,Q(q2-
import org.apache.commons.logging.Log; m/<F 5R
import org.apache.commons.logging.LogFactory; 1]
%W\RHxo
import org.flyware.util.page.Page; (,Ja
[<Os~bfOv
import com.adt.bo.Result; %0NkIQ`C
import com.adt.service.UserService; {7=WU4$
import com.opensymphony.xwork.Action; '6o`^u>
i[2bmd!H
/** xI@$aTGq
* @author Joa ljYpMv.>xG
*/ rQcRjh+E
H
publicclass ListUser implementsAction{ +^4BO`
<}EV*`w4
privatestaticfinal Log logger = LogFactory.getLog 3`fJzS% O
=& q-[JW
(ListUser.class); p<=(GY-
~_u*\]-
private UserService userService; \K?(
WxVn&c\
private Page page; wC(vr.,F
AXl!cgi
privateList users; s&dO/}3uR]
Ew
%{ i(d
/* >d8x<|D
* (non-Javadoc) *GbVMW[A>
* L$+d.=]
* @see com.opensymphony.xwork.Action#execute() m]FaEQVoE
*/ pg~zUOY
publicString execute()throwsException{ gppBFS
Result result = userService.listUser(page); h4CTTe)
page = result.getPage(); PIZ
C;K4|
users = result.getContent(); M.ZEqV+k
return SUCCESS; V$/u
} ,vPe}OKj
=\~E n5
/** r]A"Og_U
* @return Returns the page. W@I
02n2H
*/ uiktdZ/f
public Page getPage(){ R K"&l!o
return page; #TMm#?lC
} T4OguP=
[YC=d1F5
/** }.0Bl&\UK
* @return Returns the users. %1Bn_
*/ *#3*;dya]
publicList getUsers(){ G9DJa_]X
return users; ipG5l
} 5]jx5!N
TT'Ofvdc
/** 9mam ~)_ |
* @param page 86 *;z-G
* The page to set. V,V*30K5
*/ tbtI1"$
publicvoid setPage(Page page){ &!ED# gs
this.page = page; !Citzor
} /-h6`@[
UQ/qBbn
/** v @:~mwy
* @param users z"tjDP
* The users to set. )FRM_$t
*/ (=1)y'.
publicvoid setUsers(List users){ {@?G 9UypA
this.users = users; lWW+5
} 1%%'6cWWu
7_-w_"X
/** j`O7=-
* @param userService oBr.S_Qe
* The userService to set. Bs[nV}c>>
*/ z"lqrSJ:
publicvoid setUserService(UserService userService){ iZaeoy
this.userService = userService; r!7 Y'|
} zrs<#8!Y_!
} ~3gru>qI&
2R]&v;A
QdQd(4/1
Y2C9(Zk
U
h4/X
0@l`
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, -T7xK/
qos`!=g?
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 (zG.aaz*C
i(*I@ku
么只需要: ,_D"?o
java代码: d t_e
$<|ocUC7
X eoJ$PfT
<?xml version="1.0"?> 9XX>A*
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork K^zDNIQU
z%1{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- T$KF<
=
Y#FO5O%W
1.0.dtd"> Tr& }$kird
@m~RtC-Q
<xwork> n,j$D62[
iEIg:
<package name="user" extends="webwork- fQ+\;iAU
BByCMY
interceptors"> .R5y:O
99=s4*xzM
<!-- The default interceptor stack name "CQw/qZw
|Ps% M|8~
--> [mUBHYD7OI
<default-interceptor-ref y#v"GblM
<YFY{VC(
name="myDefaultWebStack"/> ]3B %8
<?h%k"5
<action name="listUser" ; |L<:x/
v>A=2i*j
class="com.adt.action.user.ListUser"> 4 o(bxs"
<param Q7gY3flg
9!U@"~yB
name="page.everyPage">10</param> -?6MU~"GK
<result 'Z&;uv,l
]XA4;7
name="success">/user/user_list.jsp</result> W`z 0"
</action> R}:KE&tq
i)ASsYG!
</package> dQb.BOI)h
R?66b{O
</xwork> Ad$n4Ze
7@}$|u:JUF
Y+~g\z-]c
%7hB&[ 5
RthT\%R
Pw0Ci
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ?7MqeR4/E
!xIm2+:(
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 oU6y4yO
%\$;(#h
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 up'
LjB;;&VCn
IJIzXU
TBrGA
E
sj?3M@l95W
我写的一个用于分页的类,用了泛型了,hoho AJ^#eY5
{yA$V0`N{
java代码: Q&'}BeUbm
JRMM? y
Wu6<\^A
package com.intokr.util; A'&n5)tb
Mwp$
import java.util.List; 4*.K'(S5fx
-62'}%?A<C
/** X|D!VX>#!
* 用于分页的类<br> R%D'`*+
* 可以用于传递查询的结果也可以用于传送查询的参数<br> <#GB[kQa
* s@hRqGd:
* @version 0.01 CzCQFqXI
* @author cheng YXurYwV
*/ 3bZIYF2@
public class Paginator<E> { 6r:?;j~l
privateint count = 0; // 总记录数 ^ci3F<?Q=
privateint p = 1; // 页编号 JO<wK
privateint num = 20; // 每页的记录数 E37<"(;
privateList<E> results = null; // 结果 2Qp Hvsl_
%1 vsN-O}8
/** obrl#(\P
* 结果总数 vDl- "!G1
*/ dz
[!-M
publicint getCount(){ [[d(jV=*
return count; <<](XgR(
} [.hyZ}B
(/-hu[:
publicvoid setCount(int count){ )*; zW!H
this.count = count; n+lOb
} 9Y>8=#.c
#_Z$2L"U
/** 'TH15r@
* 本结果所在的页码,从1开始 ay "'#[
* 7XKY]|S,'
* @return Returns the pageNo. y2]-&]&
*/ -C(b,F%%
publicint getP(){ ;S0Kh"A
return p; :1t~[-h^
} 8Og_W8
%AOja+
/** I$E.s*B9
* if(p<=0) p=1 PP:(EN1
* b=~i)`
* @param p [7_56\G4
*/ 2I*;A5$N1
publicvoid setP(int p){ b'6-dU%
if(p <= 0) nhIa175'
p = 1; Y"-^%@|p
this.p = p; 8
k3S
} =K{\p`?
+)2s-A f-
/** N3u((y/
* 每页记录数量 +w=AJdc
*/
~"UV]Udn
publicint getNum(){ u7?$b!hG^C
return num; 'v]u#/7a
} OKFtl
u%~igt@x
/** r5!/[_l
* if(num<1) num=1 @6l%,N<fou
*/ dt2$`X18
publicvoid setNum(int num){ wdUBg*X8
if(num < 1) -V: "l
num = 1; hKzSgYxP=t
this.num = num; *N{emwIq
} :1Q!$ m
detwa}h[0
/** TDd{.8qf
* 获得总页数 &ZL3{M
*/ e["2QIOe
publicint getPageNum(){ e9Nk3Sj]
return(count - 1) / num + 1; IpP~Uz
} Mi]L]-L
4wrk2x[
/** >@"Oe
* 获得本页的开始编号,为 (p-1)*num+1
>3c@x
*/ J/}:x;Y
publicint getStart(){ $V1;la!
return(p - 1) * num + 1; A45A:hqs
} }d<}FJ-,
<Qxh)@
N
/** /%Nr?V
* @return Returns the results. hUYd0qEbEt
*/ `F/Tv 5@L
publicList<E> getResults(){ _1U1(^)
return results; RIIitgV_
} \?je Wyo
3Kn_mL3V-
public void setResults(List<E> results){ 9'r:~O
this.results = results; zA[0mkC?$
} &LbJT$}V
< P`u}
public String toString(){ j\m_o% 4
StringBuilder buff = new StringBuilder e@IA20
6H'HxB4
(); !%c'$f/
buff.append("{"); :rg5Kt&
buff.append("count:").append(count); -=(!g&0
buff.append(",p:").append(p); !H ~<
buff.append(",nump:").append(num); a<@N-E xr
buff.append(",results:").append VZ\B<i
*W
kIq>
(results); |_yYLYH'
buff.append("}"); 4n4?4BEn
return buff.toString(); '{(UW.Awo
} Z.M,NR
kV38`s>+
} G>q(iF'
}X=[WCKU
,~"$k[M