Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Qfwwh`;
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 XB6N[E
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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 _-g-'Hr+N
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 V<
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分页支持类: ;bUJ+6f:
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java代码: eUzU]6h
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package com.javaeye.common.util; i=,B88ko
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import java.util.List; 6RR4L^(m
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publicclass PaginationSupport { ~)WfJ
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; ?6_"nT*}
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privateList items; MYur3lj%_
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privateint totalCount; 48R]\B<R{
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privateint[] indexes = newint[0]; yffU%
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privateint startIndex = 0; vHZX9LQU0+
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public PaginationSupport(List items, int PPuXas?i
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totalCount){ Ek gZxT_&
setPageSize(PAGESIZE); Pu/-Qpqh
setTotalCount(totalCount); (cPeee%Q
setItems(items); :)^#
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setStartIndex(0); &>+I7Ts]
} *K0j5dx
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public PaginationSupport(List items, int #QJ4o_
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totalCount, int startIndex){ R#[QoyJ
setPageSize(PAGESIZE); ?15POY ?Z
setTotalCount(totalCount); "jkw8UVz
setItems(items); QZ:]8MHl]
setStartIndex(startIndex); < -@,
} nr<}Hc^f-
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public PaginationSupport(List items, int *SMoodFBS
b#/V;
totalCount, int pageSize, int startIndex){ 0+VncL)u
setPageSize(pageSize); 1@1+4P0NF[
setTotalCount(totalCount); %^Q@*+{:f
setItems(items); !."%M^J
setStartIndex(startIndex); ;f\R$u-
} !ch[I#&J-
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publicList getItems(){ B5?c'[V9
return items; gMoyy
} 'Wx\"]:
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publicvoid setItems(List items){ SevfxR
this.items = items; g'd*TBnk
} +Y.uZJ6+
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publicint getPageSize(){ p;c_<>ws-Y
return pageSize; Z!s>AgH9u
} goBKr: &]w
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publicvoid setPageSize(int pageSize){ Wf+Cc?/4
this.pageSize = pageSize; >M8^Jgh
} 'JW_]z1
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publicint getTotalCount(){ l1iF}>F2
return totalCount; %BKR}
} Z<,CzKs+||
;/hH=IT
publicvoid setTotalCount(int totalCount){ RT_Pd\(qD
if(totalCount > 0){ tnKpn-LPA
this.totalCount = totalCount; TS~Y\Cp
int count = totalCount / cfy/*|
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pageSize; ]Gi+Z1q
if(totalCount % pageSize > 0)
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count++; ;#6<bV
indexes = newint[count]; 6\S$I5
for(int i = 0; i < count; i++){ U#~nN+SIt
indexes = pageSize * Ilt L@]e
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i; X T)hPwg.
} @88z{
}else{ cQ8$,fo
this.totalCount = 0; _nIqy&<
} 4LB9w21
} P*"AtZuY]
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publicint[] getIndexes(){ Y/eN)
return indexes; )2<B$p
} ]%Q]C
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publicvoid setIndexes(int[] indexes){ i"\AyKiJ
this.indexes = indexes; P/1UCITq}
} |<+|Du1
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publicint getStartIndex(){ @e?[oojrM
return startIndex; Oa_o"p<Lr
} -<}>YtB
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publicvoid setStartIndex(int startIndex){ CrwcYzrRWl
if(totalCount <= 0) MTFVnoZMQ_
this.startIndex = 0; ~XT
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elseif(startIndex >= totalCount) p*W ZY=Q
this.startIndex = indexes @qr3v>3X<
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[indexes.length - 1]; _.J[w6
elseif(startIndex < 0) ,j(p}t
this.startIndex = 0; luxKgcU
else{ &L~31Ayj&
this.startIndex = indexes )(|0KarF
/NN[gz
[startIndex / pageSize]; ,h(f\h(9
} JXy667_
} /K<GN7vN
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publicint getNextIndex(){ Xw}Y!;<IEu
int nextIndex = getStartIndex() + glKs8^W
3
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pageSize; e5/DCz
if(nextIndex >= totalCount) )hZ}$P1
return getStartIndex(); _%p9B#X<>
else /CQQ^/
return nextIndex; @2Y]p.$q
} ZX5A%`<M
Z :i"|;
publicint getPreviousIndex(){ .Zo9^0`C
int previousIndex = getStartIndex() - ~C*6V{Tj
a ~iEps
pageSize; $j4?'-i=e
if(previousIndex < 0) Kg0\Pvg8?T
return0; [m+O0VK$
else ]v,y(yl
return previousIndex; ]!Aze^7;
} ~JmxW;|_x)
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} O@(.ei*HJ!
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抽象业务类 d8q$&(]<
java代码: fjZveH0
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/** N+@@EOmH
* Created on 2005-7-12 /a/uS3&
*/ E_I6
package com.javaeye.common.business; yar IR|
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import java.io.Serializable;
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import java.util.List; d?qO`-
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import org.hibernate.Criteria; :tDGNz*zG
import org.hibernate.HibernateException; pS)X\Xyw
import org.hibernate.Session; )mZy>45
import org.hibernate.criterion.DetachedCriteria; 3z. >b
import org.hibernate.criterion.Projections; :V1ZeNw
import l0bT_?LhK
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org.springframework.orm.hibernate3.HibernateCallback; Nn4Kt,KY
import !I+u/f?TO7
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org.springframework.orm.hibernate3.support.HibernateDaoS 1Y0oo jD
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upport; `DY4d$!4
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import com.javaeye.common.util.PaginationSupport; e5\1k#@
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public abstract class AbstractManager extends 7Sv5fLu2
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HibernateDaoSupport { xMGd'l?
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privateboolean cacheQueries = false; 3Eux-C!t
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privateString queryCacheRegion; R =c
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publicvoid setCacheQueries(boolean 6h*bcb#C
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cacheQueries){ iQR})=Q
this.cacheQueries = cacheQueries; ?#y<^oNM
} [5#/&k{
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publicvoid setQueryCacheRegion(String x};g!FYfkB
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queryCacheRegion){ 6Kc7@oO~
this.queryCacheRegion = /PuWJPy;
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queryCacheRegion; 2%%U)|39mB
} "_}D{ws1
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publicvoid save(finalObject entity){ T:n^$RiT
getHibernateTemplate().save(entity); #IJKMSGw?E
} cG"<*Xi <
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publicvoid persist(finalObject entity){ 4Lq]yUj
getHibernateTemplate().save(entity); q&S.C9W
} XD>@EYN<X
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publicvoid update(finalObject entity){ KT?s\w
getHibernateTemplate().update(entity); x%7x^]$
} qk"=nAJX
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publicvoid delete(finalObject entity){ bL[W.O0
getHibernateTemplate().delete(entity); W8rn8Rh
} .`=PE&xq
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publicObject load(finalClass entity, ;lt;]7
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finalSerializable id){ ?uBC{KQ}Y
return getHibernateTemplate().load /Bu5kBC
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(entity, id); iR =aYT~
} ~ZC=!|Q#
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publicObject get(finalClass entity, k&;L(D
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finalSerializable id){ }
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return getHibernateTemplate().get ar}759
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(entity, id); >k-poBw
} :Djp\
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publicList findAll(finalClass entity){ m1;jS|
return getHibernateTemplate().find("from kniMXeiu
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" + entity.getName()); Q{-r4n|b
} jX,~iZ_B
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publicList findByNamedQuery(finalString jO.E#Ei}~
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namedQuery){ m"}G-#
return getHibernateTemplate C5
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().findByNamedQuery(namedQuery); (8R
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} l<6/ADuS
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publicList findByNamedQuery(finalString query, y70gNPuTOD
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finalObject parameter){ ?H?r!MZ%
return getHibernateTemplate fok#D>q
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().findByNamedQuery(query, parameter); )]R8
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} P&;I]2#
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publicList findByNamedQuery(finalString query, >MH@FnUL
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finalObject[] parameters){ L|?tcic
return getHibernateTemplate HC+R:Dz
(PF (,B
().findByNamedQuery(query, parameters); /2q%'"x(
} m|[Hhw=f
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publicList find(finalString query){ gy.;
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return getHibernateTemplate().find }Of^Y@{q.
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(query); WYL.J5O
} :08UeEy
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publicList find(finalString query, finalObject ^M"g5+q
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parameter){ /~:ztv\$M"
return getHibernateTemplate().find +zvK/Fj2q
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(query, parameter); >e%Po,Fg$
} Cpl)byb
q I}Zg)q]
public PaginationSupport findPageByCriteria -_+0[Nb.
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(final DetachedCriteria detachedCriteria){ p-Ju&4fS
return findPageByCriteria 2bmppDk
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); [B
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} u CXd%
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public PaginationSupport findPageByCriteria NNX/2
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(final DetachedCriteria detachedCriteria, finalint cQjJ9o7
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startIndex){ KH-.Z0
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return findPageByCriteria SWt"QqBU
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(detachedCriteria, PaginationSupport.PAGESIZE, O7W}Z1G
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startIndex); Oqyh{q%]
} +e\u4k {3V
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public PaginationSupport findPageByCriteria lc^%:#@
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(final DetachedCriteria detachedCriteria, finalint {|cA[#j#
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pageSize, v|e>zm<
finalint startIndex){ I`|>'$E[r
return(PaginationSupport) Ua4} dW[w
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getHibernateTemplate().execute(new HibernateCallback(){ rqIt}(J
publicObject doInHibernate V+ Z22
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(Session session)throws HibernateException { < mxUgU
Criteria criteria = K vgZx(.
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detachedCriteria.getExecutableCriteria(session); j>U.(K
int totalCount = ~vgW:]i
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((Integer) criteria.setProjection(Projections.rowCount *m7e>]-
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()).uniqueResult()).intValue(); ; -3M
criteria.setProjection W $y?~2
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(null); x-"7{@lz
List items = N4Ym[l
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criteria.setFirstResult(startIndex).setMaxResults Rj8l]m6U9
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(pageSize).list(); :c\NBKHv*
PaginationSupport ps = lm+wjhkN
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new PaginationSupport(items, totalCount, pageSize, /w|YNDA]j
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startIndex); ?lTQjw{
return ps; U|>Js!$
} a P`;Nr=
}, true); !U91
} - na]P3 s
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public List findAllByCriteria(final N7NK1<vw2
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DetachedCriteria detachedCriteria){ >uVG]
return(List) getHibernateTemplate F$caKWzny5
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().execute(new HibernateCallback(){ 7':|f "
publicObject doInHibernate aW"BN 5eM>
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(Session session)throws HibernateException { I?1^\s#L
Criteria criteria = % $J^dF_0
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detachedCriteria.getExecutableCriteria(session); Q>|<R[.7
return criteria.list(); V
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} p4/D%*G^`
}, true); ;2U`?"
} 2JbCYCTC
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public int getCountByCriteria(final D;Z\GnD
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DetachedCriteria detachedCriteria){ Wg#>2)>
Integer count = (Integer) <h^vl-L>
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getHibernateTemplate().execute(new HibernateCallback(){ 8garRB{
publicObject doInHibernate ~; MRQE
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(Session session)throws HibernateException { f>Ge
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Criteria criteria = + 505
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detachedCriteria.getExecutableCriteria(session); VlKWWQj
return #
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criteria.setProjection(Projections.rowCount 3t8VH`!mL{
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()).uniqueResult(); -&+[/
} VLR W,lR9O
}, true); Wu:evaZ:i
return count.intValue(); `CRW2^g
} pJV<#<#Z
} t1D6#JP(a
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用户在web层构造查询条件detachedCriteria,和可选的 UZqr6A(/H
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 oh|Q&R
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PaginationSupport的实例ps。 \\6/"
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ps.getItems()得到已分页好的结果集 mkgDg y
ps.getIndexes()得到分页索引的数组 6?r}bs6Msx
ps.getTotalCount()得到总结果数 '};pu;GA7
ps.getStartIndex()当前分页索引 @2V#bK
ps.getNextIndex()下一页索引 L_Z>*s&
ps.getPreviousIndex()上一页索引 u1rT:\G1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 FK<1SOE
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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 =5J}CPKbZI
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一下代码重构了。 `i;f
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我把原本我的做法也提供出来供大家讨论吧: M/T
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首先,为了实现分页查询,我封装了一个Page类: q9|'!m5K
java代码: `5:b=^'D/
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/*Created on 2005-4-14*/ 8!sl) R
package org.flyware.util.page; JZB7?@h%
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/** <A<N? `"
* @author Joa 4YMX;W
* s9X?tWuL
*/ 0sIwU!=vm
publicclass Page { T'!7jgk{:
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/** imply if the page has previous page */ VB o=*gn,$
privateboolean hasPrePage; C8ek{o)%W
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/** imply if the page has next page */ Y'H|Tk^`
privateboolean hasNextPage; P 9c!
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/** the number of every page */ NSI$uS6
privateint everyPage; ;LD!eWSK,
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N;
/** the total page number */ `|(S]xPHM
privateint totalPage; c&X2k\
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/** the number of current page */ )B)ecJJ_
privateint currentPage; lub_2Cb|j
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/** the begin index of the records by the current ?h\fwF3
0 7b=Zhh
query */ K,j'!VQA4g
privateint beginIndex; v(=?@tF}E
/F@CrNFb(
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/** The default constructor */ 37<^Oly!
public Page(){ > zA*W<g
?`hA :X<
} 4M*Z1
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/** construct the page by everyPage q]Vxf!0*>
* @param everyPage "rA-u)Te
* */ N2 4J!L
public Page(int everyPage){ 4g+Dp&U
this.everyPage = everyPage; r:3h2J[_
} 1Be/(pSc
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/** The whole constructor */ -kzp>=
public Page(boolean hasPrePage, boolean hasNextPage, iVT)V>U p
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int everyPage, int totalPage, CFXr=.yz
int currentPage, int beginIndex){ swKqsN.
this.hasPrePage = hasPrePage; PCx:
this.hasNextPage = hasNextPage; Q@ua
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this.everyPage = everyPage; 'D'H)J
this.totalPage = totalPage; >t#5eT`_ w
this.currentPage = currentPage; i"#pk"@`
this.beginIndex = beginIndex; m`BE{%
} 7bk`u'0%
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/** Z H2
* @return &yRR!1n)H
* Returns the beginIndex. Gv&%cq1
*/ ~jJF&*)
publicint getBeginIndex(){ jP#I](\eG
return beginIndex; `{%ImXQF
} #+&"m7
s
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/** a$K6b5`>Rs
* @param beginIndex >-,$
* The beginIndex to set. +,]_TxL|C
*/ 0YZ66VN!
publicvoid setBeginIndex(int beginIndex){ :{,k F
this.beginIndex = beginIndex; cs9"0&JX
} l6-
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6zIK%<
/** W[f%m0
* @return )>tT""yEl
* Returns the currentPage. %/2OP &1<
*/ l?A~^4(5a/
publicint getCurrentPage(){ []doLt;J
return currentPage; s.^+y7$
} Th
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/** 5,|of{8
* @param currentPage lWDSF]ZYV
* The currentPage to set. }Te+Rv7{E
*/ 'w0?-
publicvoid setCurrentPage(int currentPage){ ASB3|uy _
this.currentPage = currentPage; lS|F&I5j
} {A~3/M%74;
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/** !?" pnKb}
* @return Ap~6Vu
* Returns the everyPage. F. I\?b
*/ EMPujik-
publicint getEveryPage(){ FqZD'Uu7
return everyPage; v6H!.0
} XMzQ8|]
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/** JkI|Ojmm/
* @param everyPage hcpe~spz9|
* The everyPage to set. ~x[(1
*/ GL _hRu
publicvoid setEveryPage(int everyPage){ J|
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this.everyPage = everyPage; `YY07(%
} FE1'MUT_
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/** F-XMy>9
* @return *^KEb")$
* Returns the hasNextPage. <sn,X0W
*/ PZY6
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publicboolean getHasNextPage(){ e~SRGyIww
return hasNextPage; ;Fd1:"1pP
} /8 yv8
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/** dkW7k^g
* @param hasNextPage pgW^hj\
* The hasNextPage to set. %jJIR88
*/ Q9c*I,Oj
publicvoid setHasNextPage(boolean hasNextPage){ N/[!$B0H@
this.hasNextPage = hasNextPage; nbW.x7
} \~r_S
ps^["3e
/** *uSlp_;kB
* @return ZENblh8fs
* Returns the hasPrePage. +Ht(_+To1
*/ _;R#B`9Iu
publicboolean getHasPrePage(){ TrNh,5+b
return hasPrePage; a]J>2A@-I
} !}5+hj!6
Vh^ :.y
/** qoZe<jW (
* @param hasPrePage 2V~uPZ
* The hasPrePage to set. m{&lU@uL
*/ vs>Pd |p;
publicvoid setHasPrePage(boolean hasPrePage){ (w`_{%T
this.hasPrePage = hasPrePage; a5(9~.9
} Z{gDEo)
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/** F$'po#
* @return Returns the totalPage. KO/#t~
* |[p]])
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*/ A8k $.E
publicint getTotalPage(){ k@pEs# a
return totalPage; G
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} WR u/7$8
D&=+PAX
/** X5(oL
* @param totalPage ><$V:nsEO
* The totalPage to set. 3T>6Q#W5eO
*/ %L$?Mey
publicvoid setTotalPage(int totalPage){ 8w#4T:hsuN
this.totalPage = totalPage; 7#N
?{3i
} "Xl"H/3r
DHbS=Iih
} n<F3&2w
ItVVI"-
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 4sfq,shRq
Pb1.X9*8c
个PageUtil,负责对Page对象进行构造: EztuVe
java代码: Y\
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/*Created on 2005-4-14*/ />uE)R$
package org.flyware.util.page; 06`caG|]-M
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import org.apache.commons.logging.Log; j3S!uA?
import org.apache.commons.logging.LogFactory; xgtx5tg
o=PW)37>
/** b8[
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* @author Joa jaIcIc=Pf
* jthyZZ
*/ y 5?kv-"c
publicclass PageUtil { '}OAl
m 0Uu2Z4
privatestaticfinal Log logger = LogFactory.getLog 9H53H"5q
G @]n(\7Y
(PageUtil.class); UMMGT6s,E8
_`Y%Y6O1/
/** P,7R/-u 5D
* Use the origin page to create a new page #iRd2Qj%
* @param page (Zej\lEN
* @param totalRecords |`|zo+aW
* @return .4Mc4'
*/ %WqUZ+yy
publicstatic Page createPage(Page page, int ?B`c<H"
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totalRecords){ _s:5)
return createPage(page.getEveryPage(), 07\]8^/G
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page.getCurrentPage(), totalRecords); Cd_H<8__
} @Hr1.f
j9}.U \
/** g>a%
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* the basic page utils not including exception 6aWNLJ@
gQeoCBCE
handler Z4{N|h?
* @param everyPage f%P#.
* @param currentPage Gsy90
* @param totalRecords )Q<u0AxAn
* @return page sqj8I"<`
*/ R-2Abyts2
publicstatic Page createPage(int everyPage, int roIc1Ax:
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currentPage, int totalRecords){ Smd83W&
everyPage = getEveryPage(everyPage); #9A*B bY
currentPage = getCurrentPage(currentPage); LX(`@-<DH
int beginIndex = getBeginIndex(everyPage, aq9Ej]1b
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currentPage); :Yi 4Ia
int totalPage = getTotalPage(everyPage, E<
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Lf;Uv[^c
totalRecords);
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boolean hasNextPage = hasNextPage(currentPage, z:08;}t
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totalPage); o KY0e&5
boolean hasPrePage = hasPrePage(currentPage); 2W/*1K}
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returnnew Page(hasPrePage, hasNextPage, n]K {-C;
everyPage, totalPage, "&\]1A}Z-x
currentPage, kcP&''
ciN*gwI)
beginIndex); /vqsp0e"H
}
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xz}=C:s
privatestaticint getEveryPage(int everyPage){ fh&Q(:ZU
return everyPage == 0 ? 10 : everyPage; nd h\+7
} 7[M@;$
irn
}.e
privatestaticint getCurrentPage(int currentPage){ ]w!=1(
return currentPage == 0 ? 1 : currentPage; De49!{\a
} TEbE-h0)]
K3`48,`?wA
privatestaticint getBeginIndex(int everyPage, int bhCAx W
?'OL2~
currentPage){ x'
3kHw
return(currentPage - 1) * everyPage; :]`JcJ
} k-$J #
=fI0q7]ndz
privatestaticint getTotalPage(int everyPage, int 5pq9x4&
l
i2/"~l
totalRecords){ t=dZM}wj_\
int totalPage = 0; R-\"^BV#Z
4$4n9`odE
if(totalRecords % everyPage == 0) a0cW=0l=
totalPage = totalRecords / everyPage; L%f$ &
else +/Vzw
totalPage = totalRecords / everyPage + 1 ; =
8\'AU
&fifOF#[e
return totalPage; #M8>)o c
} &3Mps[u:h
aGmbB7[BZ
privatestaticboolean hasPrePage(int currentPage){ _P{v=`]Eu
return currentPage == 1 ? false : true; yx/qp<=
} |(R[5q
"QV1G'
privatestaticboolean hasNextPage(int currentPage, SrXuiiK
q^b_'We_9
int totalPage){ z0 _/JwJn
return currentPage == totalPage || totalPage == zKaEh
,9/s`o
0 ? false : true; +F6R@@rWr
} A*3R@G*h
8hvh
xp
X[o"9O|<
} CV6W)B%Se
>Y&o2zJy
Re'Ek
'>|5
DZ0\pp?S
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。 }F
(lffb
+PkN~m`
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 \(xQ'AQ-
v7-
d+P=
做法如下: @EcY&mP)
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 BGVy
\F<
w^QqYUL${
的信息,和一个结果集List: |)u|@\{
java代码: ]ch=D
W[j7Vi8v
XY`2>7
/*Created on 2005-6-13*/ @7<m.?A!
package com.adt.bo; >eaK@u-'0
JZrUl^8E
import java.util.List; v4wXa:CJ
UHUO9h
import org.flyware.util.page.Page; rzgzX
Zu %oIk
/** @?"t&h
* @author Joa Y{ 2xokJ N
*/ )ur&Mnmm
publicclass Result { X+XbIbUuL
nzORG
private Page page; ecy41y'~:
&,@wLy^T
private List content; 5Ai$1'*p
J'y*>dW
/** t9
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* The default constructor esQRg~aCGy
*/ tc<t%]c
public Result(){ )?PRG=
super(); E|Z7art
} R|H_F#eVn}
\:wLUGFl5
/** \ g[A{
* The constructor using fields 6WnGP>tc.
* 7 }sj&
* @param page 6KI< J*Wz`
* @param content )hai?v~g
*/ ;M Z@2CO
public Result(Page page, List content){ LlG~aGhel
this.page = page; 8?7:sfc
this.content = content; iP~dH/B|v
} h8_~ OX
mg^\"GC*8
/** #`H^8/!e
* @return Returns the content. wh;E\^',n
*/ in6iJ*E@'
publicList getContent(){ L)ry!BuHI
return content; #FV(a ~
} u +OfUBrf
v{2Vg
/** ^~dvA)bH
* @return Returns the page. +(<}`!9M*
*/ ~X
-.@k'
public Page getPage(){ v+Q#O[
return page; (_lc< Bj
} 'u2Qq"d+
Sm%MoFf
/** 2tqO%8`_
* @param content 4x:Odt5
* The content to set. =`]yq;(C7j
*/ LvNk:99:<
public void setContent(List content){ VgNt
this.content = content; [2,u:0 "
} jP";ll|c
XDJQO /qN
/** qlg~W/
* @param page {9Op{bZ
* The page to set. :I }_
*/ f6P5J|'
publicvoid setPage(Page page){ g3%t+>$*
this.page = page; }?Y+GT"E
} VmB/X))
} (IR'~:W
k|7XC@i]%
'm=9&?0S
o;JBe"1
I
-obfyije
2. 编写业务逻辑接口,并实现它(UserManager, jjm-%W@
STmCj
UserManagerImpl) ud-.R~f{e
java代码: ;D[b25
f:TC;K
3;`93TO{
/*Created on 2005-7-15*/ @]HV:7<q
package com.adt.service; JqH2c=}-
OX4+1@$tk
import net.sf.hibernate.HibernateException; EQ>bwEG
.-N9\GlJ,d
import org.flyware.util.page.Page; ;r[=q u\
um&e.V)N
import com.adt.bo.Result; B%9[
:OBggb#?!
/** $hO8
S =
* @author Joa qD#-q vn
*/ qhpq\[U6in
publicinterface UserManager { [:!#F7O-
,9"</\]`
public Result listUser(Page page)throws <S0!$.Kg*<
fK^FD&sF
HibernateException; ki^[~JS>'
N2tvP+Z6D
} i\rI j0+
@Cm"lv.hz
9#6ilF:F
H$ xSl1>E
tO?*x/XC{
java代码: cVn7jxf
~%Yh`c
EP
)11/BB\v
/*Created on 2005-7-15*/ BoIe<{X(9
package com.adt.service.impl; 7XWgY%G
qTyU1RU$9^
import java.util.List; {M E|7TS=
qr=U=oK
import net.sf.hibernate.HibernateException; 4[.-
a&!}
3g|O2>*?
import org.flyware.util.page.Page; S,S_BB<Y[b
import org.flyware.util.page.PageUtil; 7!JoP?!
h2aJa@;S
import com.adt.bo.Result; Ok({Al1A,w
import com.adt.dao.UserDAO; }+ #ag:M
import com.adt.exception.ObjectNotFoundException; qm]ljut
import com.adt.service.UserManager; #>ci!4Gz=Z
7qXgHrr0|U
/** &"C1XM
* @author Joa #8|;Q`Or:
*/ %v~j10e
publicclass UserManagerImpl implements UserManager { 7X}_yMxc
(DKpJCx
private UserDAO userDAO; J(/
eR,ak
on&N=TN
/** 2#W%--
* @param userDAO The userDAO to set. )vGRfFjw_
*/ GJy,)EO6{
publicvoid setUserDAO(UserDAO userDAO){ b<.+WkO
this.userDAO = userDAO; )_2!1
} 'A8T.BU
Cfz1\a&V{
/* (non-Javadoc) ]\r~"*TZ
* @see com.adt.service.UserManager#listUser 9y]$c1
1<59)RiO>
(org.flyware.util.page.Page) rhn*kf{8
*/ "v*RY "5#
public Result listUser(Page page)throws EUna_ 4=
&<^@/osi
HibernateException, ObjectNotFoundException { !>S'eXt
int totalRecords = userDAO.getUserCount(); `&9#!T.
if(totalRecords == 0) <"[}8
throw new ObjectNotFoundException Dh +^;dQ6
PL+fLCk,I
("userNotExist"); 9'5,V{pj
page = PageUtil.createPage(page, totalRecords); `8'T*KU
List users = userDAO.getUserByPage(page);
Ha
C?,
returnnew Result(page, users); B~PF <8h5
} "F[VqqD
l1W5pmhK]'
} x-Mp6
6o1.?t?
QdW%5lM+
Y?%6af+
@MB;Ez
v
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >9u6@
5E!|-xD
询,接下来编写UserDAO的代码: Ugdm"
3. UserDAO 和 UserDAOImpl: ~C!vfPC
java代码: B|GJboQ
Fsq S)
HZK0Ldf
/*Created on 2005-7-15*/ ?4lAL
package com.adt.dao; SV\x2^Ea0
HWefuj
import java.util.List; M $~h(3
f1~3y}7^Jq
import org.flyware.util.page.Page; [#9ij3vxd
BEI/OGp
import net.sf.hibernate.HibernateException; #JLDj(a?
9C4l@jrF
/** ~l}TlRqL
* @author Joa ^c(PZ,/#JB
*/ G0(c@FBK
publicinterface UserDAO extends BaseDAO { ka>RAr J
KT g$^"\
publicList getUserByName(String name)throws <hK$Cf_
PO%]Jme
HibernateException; I8Zp#'|U
"BVz5?
publicint getUserCount()throws HibernateException; n~)Y% xe[U
=V,'f
publicList getUserByPage(Page page)throws h
|lQTT
&^uzg&,;
HibernateException; U/iAP W4U
6=@n
b3D%
} S|>Up%{n[
I Mv^ 9T:
Qs?+vk?*h
s?6 7@\
d#b{4zF"
java代码: q?^0
o\
q!H3JL
#/tdZ0
/*Created on 2005-7-15*/ - 5k4vx
N}
package com.adt.dao.impl; OUdeQO?
Ch.T}%
import java.util.List; "=".ne
_+Q$h4t
import org.flyware.util.page.Page; Asn0&Ys4
Gqia@>T4*N
import net.sf.hibernate.HibernateException; W?l .QQk
import net.sf.hibernate.Query; vfbe=)}[
v :HgpZo+
import com.adt.dao.UserDAO; b?bYPN+
zgRP!q<9tt
/** I?Zs|A
* @author Joa ^6LFho4
*/ {tT`It
public class UserDAOImpl extends BaseDAOHibernateImpl ~NcJLU!au
NuooA
implements UserDAO { cdfll+
g~y9j88?
/* (non-Javadoc) apMYBbC
* @see com.adt.dao.UserDAO#getUserByName c0qv11,:t
kCwTv:)
(java.lang.String) a:|4q
*/ aEk*-v#{
publicList getUserByName(String name)throws 7IHD?pnZ
6m.Ku13;
HibernateException { Zn/9BO5
String querySentence = "FROM user in class t!T}Pg(Bo
F889JSZ%
com.adt.po.User WHERE user.name=:name"; jF3!}*7,
Query query = getSession().createQuery R^2Uh$kk{A
"{Be k<
(querySentence); o5D" <-=>
query.setParameter("name", name); H4m6H)KOG
return query.list(); 23f[i<4e
} PPqTmx5S
j^ _I{
/* (non-Javadoc) 3N
bn|_`(
* @see com.adt.dao.UserDAO#getUserCount() !Q(xOc9>Ug
*/ }g*-Ty
publicint getUserCount()throws HibernateException { @*uX[)
int count = 0; 9V],X=y~
String querySentence = "SELECT count(*) FROM J@GfO\
o
) ]%9Tgn
user in class com.adt.po.User"; `JE>GZY
Query query = getSession().createQuery 4'd{H
Rs
#LN
I&5
(querySentence); \i,cL)HM
count = ((Integer)query.iterate().next rq1kj 8%2
HEuM"2{DMM
()).intValue(); *3/7wSV:
return count; Hr+-ndH!Pq
} VBX#
!K1Q
r$#G%FMv
/* (non-Javadoc) [[e |GQ
* @see com.adt.dao.UserDAO#getUserByPage 3opLLf_g
-/-6Td1JY>
(org.flyware.util.page.Page) //
}8HY)>
*/ =_'cG:=)
publicList getUserByPage(Page page)throws VRX"
@uCD
)R^Cq o'
HibernateException { /,Rca1W
String querySentence = "FROM user in class nFfCw%T?
}91mQ`3
com.adt.po.User"; H< ;Fb;b
Query query = getSession().createQuery *!'&:
mU=6"A0
U
(querySentence); |\a:]SlH
query.setFirstResult(page.getBeginIndex()) Xo@YTol
.setMaxResults(page.getEveryPage()); nF'xV44"
return query.list(); <c ovApx
} ~}5Ml_J$,l
30_un
} U R@BSK'
r}\h\ {
Is@a,k
&'7"i~pC
~B&*7Q7
至此,一个完整的分页程序完成。前台的只需要调用 pIu H*4Vz
uit-Q5@~
userManager.listUser(page)即可得到一个Page对象和结果集对象 UNQRtR/
w`}9/s;$
的综合体,而传入的参数page对象则可以由前台传入,如果用 s1vrzze
v\Y}(fD
webwork,甚至可以直接在配置文件中指定。 TJXraQK-=
e_=pspnZ
下面给出一个webwork调用示例: Z02s(y=k1
java代码: 16QbB;
z`/.v&<>V
#Q3PzDfj
/*Created on 2005-6-17*/ Fd[h9 G
package com.adt.action.user; %?f:"
$a^isd4
import java.util.List; qd+[ShrhqZ
}IN_5o((
import org.apache.commons.logging.Log; >J}n@MZ
import org.apache.commons.logging.LogFactory; 5!ubY
6Ph
import org.flyware.util.page.Page; HJ qQlEq
F4rKFMr
import com.adt.bo.Result; sdf%
import com.adt.service.UserService; p%"yBpSK
import com.opensymphony.xwork.Action; ^v!im\ r
DvX3/z#T
/** Iv(Qa6(
* @author Joa )E:,V~< 8
*/ Iz)hz9k
publicclass ListUser implementsAction{ P/pjy
y5/6nvH_6
privatestaticfinal Log logger = LogFactory.getLog qijcS2E6S
(kC} ,}
(ListUser.class); tQ~<i %;
~g1, !Wl
private UserService userService; X
B*}P
m*!f%}T
private Page page; ^$IZLM?E~
14D7U/zer
privateList users; *w/WHQ`xI
_;:rkC fj
/* 8rwYNb.P
* (non-Javadoc) R|1xXDLm*E
* 0HR|aqPo
* @see com.opensymphony.xwork.Action#execute() _Dj<Eu_
*/ 23-t$y]
publicString execute()throwsException{ h/Hl?O8[
Result result = userService.listUser(page); D;zWksq
page = result.getPage(); 5!AV!A_Jp
users = result.getContent(); f>r3$WKj
return SUCCESS; rer|k<k;]G
} voV:H[RD9
-+}5ma
/** _(6`{PWY
* @return Returns the page. ]G0dS
Fh{j
*/ '_qQrP#
public Page getPage(){ rKzlK 'U
return page; P>Q{He:
} %l}Q?Z
j
u*fyt
/** 1OJ*wI*
* @return Returns the users. |mxNUo-
*/ S<nP80C
publicList getUsers(){ :p<kQ4
return users; bar0{!Y"
} ivzAlwP
$;Vc@mYGW;
/** i3Hz"Qs;
* @param page Sty!atEWT
* The page to set. jJ
aV
*/ lwOf)jK:J
publicvoid setPage(Page page){ s>|Z7[*
this.page = page; 0e+W/Tq
} >5;N64]!)
sEce{"VC
/** z2w;oM$g
* @param users {'h_'Y`bOQ
* The users to set. ;1W6"3t-Y
*/ $Z;B QJVH
publicvoid setUsers(List users){ zF5q=9 4$
this.users = users; \=!H 2M
} pI7Ssvi^
X9fNGM1
/** ,+tPRkwA^
* @param userService 3J%V%}mD
* The userService to set. ~G>jw"r
*/ TbLe6x
publicvoid setUserService(UserService userService){ vv+D*e&<
this.userService = userService; *hVb5CS
} BeK2;[5C
} Ge~q3"
k-"<{V
]9jZndgC
__!m*!sd
Y@Y`gF6F
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, #{!O,`qD
-(*nSD9
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 vwKw?Z0%J
[O2h-`
么只需要: +YTx
java代码: &Y1`?1;nw
uBmxh%]C~
Wo{K}
<?xml version="1.0"?> I:#Ok+
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork :pwa{P
|;P^clS3
1.0//EN" "http://www.opensymphony.com/xwork/xwork-
tPA:_
'61i2\[lZQ
1.0.dtd"> 91up^
x;u ~NKy
<xwork> &Yp+k}XU
Xo Y7/&&
<package name="user" extends="webwork- @,k7xm$u
nfX12y_SXL
interceptors"> td >,TW=A*
.Gh%p`<
<!-- The default interceptor stack name lop uf/U0
B{p4G`$i1
--> Fn!SGX~kx$
<default-interceptor-ref ibJl;sJ
7JI:=yY!>:
name="myDefaultWebStack"/> !z MDP/V
b^ sb]bZW
<action name="listUser" e*:}$u8a
{"m0)G,G
class="com.adt.action.user.ListUser"> p1D()-
<param HT"gT2U+
xW>ySEf
name="page.everyPage">10</param> lkA^\+Ct
<result \~>e_;
ExCM<$,
name="success">/user/user_list.jsp</result> WL l_'2h
</action> T~X41d\
D`VFf\7
</package> Vclr2]eV4O
EMlIxpCn:
</xwork> %c X"#+e
>,"sHm}l%
,=|4:F9
`
W4dx&
ne4c%?>t
CWi8Fv
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 0(gq;H5x'
W"Q!|#;l.
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。 E-fr}R}
QHzgy?
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 z(me@P!D~
DyfsTx
Mra35
;cKH1
9t K>gwb
我写的一个用于分页的类,用了泛型了,hoho Qz+sT6js-
jl}$HEI5m}
java代码: d(7NO;S8
:l,OalO
h^oH^moq<
package com.intokr.util; #.ct5
1fFj:p./l_
import java.util.List; LjaGyj>)
UTCzHh1
/** ,l HLH
* 用于分页的类<br> y-9+a7j
* 可以用于传递查询的结果也可以用于传送查询的参数<br> PKf:O
* exDkq0u]
* @version 0.01 qu~X.pW
* @author cheng 81F,Y)x.
*/ dz%EM8
public class Paginator<E> { uS<_4A;sD,
privateint count = 0; // 总记录数 $^_|j1z#i
privateint p = 1; // 页编号 nt ,7u(
privateint num = 20; // 每页的记录数 -M4p\6)Ge
privateList<E> results = null; // 结果 ``|AgIg
h*w6/ZL1
/** ? \m3~6y
* 结果总数 S1bAu
<
*/ *Zbuq8>
publicint getCount(){ G[Tl%w
return count; cozXb$bBY
} a#0;==#
rzeLx Wt
publicvoid setCount(int count){ /ty?<24ko
this.count = count; B,vOsa"x6`
} tous#(&pK
S8vV!xO
/** E m{aM
* 本结果所在的页码,从1开始 XOy2lJ/
* w%a8XnW]1
* @return Returns the pageNo. GABQUmtH
*/ -rSIBc:$8
publicint getP(){ {fDTSr?/
return p; vF4]ux&
} |L::bx(
#X`8dnQZ
/** aeP[+ I9
* if(p<=0) p=1 cpZc9;@IC
* S%mfs!E>
* @param p Ug%_@t/?
*/ jQh^WmN
publicvoid setP(int p){ 5[gh|I;D
if(p <= 0) !EBY@ Y1
p = 1; 0Scm?l3
this.p = p; \9{F5Sz
} E167=BD9<
e3[:D5
/** T~xwo
* 每页记录数量 3
hKBc0
*/ oxz{ ejd{
publicint getNum(){ kc$)^E7
return num; +wO#'D
} pyZ9OA!PD
~DF:lqwWP
/** TNwKda+
* if(num<1) num=1 p(JlvJjo
*/ v;EQ, NL
publicvoid setNum(int num){ DcD{*t?x
if(num < 1) e Y$qV}
num = 1; Uh6 '$0
this.num = num; 1B=>_3_
} ,*svtw:2')
!Ng=Yk>3
/** 8wZf]_
* 获得总页数 PWr(*ZP>hI
*/ =8{WZCW5
publicint getPageNum(){ vH[47Cv G5
return(count - 1) / num + 1; b1#dz]
} YB( Gk;]
$md%xmQ[
/** c=O,;lWFqm
* 获得本页的开始编号,为 (p-1)*num+1 &a0r%L()X
*/ g"VMeW^
publicint getStart(){ dl-l"9~;
return(p - 1) * num + 1; b7`D|7D
} `:NaEF?Sj
d3Mva,bw<
/** G3i !PwW
* @return Returns the results. =+:{P?*}
*/ :mppv8bh
publicList<E> getResults(){ YIRZ+H<Q
return results; \nNXxTxX!
} dihjpI_
Uz7oL8
public void setResults(List<E> results){ %r\n%$@_
this.results = results; 21X`h3+=
} Dim>
7Wbh
"r4AY
public String toString(){ N2r/ho}8
StringBuilder buff = new StringBuilder uN*KHE+h
;bzX%f?|G
(); F9"w6;hh
buff.append("{"); Ex amD">T
buff.append("count:").append(count); Uu
s.
buff.append(",p:").append(p); ;*TIM%6#
buff.append(",nump:").append(num); S[3iA~)Z-
buff.append(",results:").append K)tQ]P
"p&Y^]
(results); CqMhk
buff.append("}"); Cwa^"r3P1
return buff.toString(); (& "su3z
} hXIro
HAz By\M{
} Fxs;Fp
;ea]$9
z;f2*F