Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _C\b,D}p
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 m+"%Jd{q
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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 b1cd5
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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 5
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分页支持类: /<Et
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java代码: 8ic_|hfY
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package com.javaeye.common.util; BKEB,K=K@
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import java.util.List; W|
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publicclass PaginationSupport { o_n.,=/cZ
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publicfinalstaticint PAGESIZE = 30; ?6bE!36
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privateint pageSize = PAGESIZE; Me>'QVr
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privateList items; 9P$'ON'"
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privateint totalCount; y=Hl ~ev`9
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privateint[] indexes = newint[0]; z6qC6Ck|
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privateint startIndex = 0; /MC\!,K
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public PaginationSupport(List items, int "$&F]0
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totalCount){ 2h!3[{M\
setPageSize(PAGESIZE); ?H`LrL/k
setTotalCount(totalCount); V1G]LM
setItems(items); !QovpO">z
setStartIndex(0); )94R\f
} r%m2$vx#
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public PaginationSupport(List items, int Mx
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totalCount, int startIndex){ x@~V975Y
setPageSize(PAGESIZE); [~3p+
setTotalCount(totalCount); *)1,W+A5L
setItems(items); {IVqV6:
setStartIndex(startIndex); b/EvcN8 }
} )+G(4eIT
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public PaginationSupport(List items, int =bzTfki
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totalCount, int pageSize, int startIndex){ N?XN$hwdZ
setPageSize(pageSize); ,]MX&]
setTotalCount(totalCount); mR^D55k
setItems(items); k#.co~kS
setStartIndex(startIndex); @&+
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} <3bh-)
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publicList getItems(){ 3,?y !
return items; saV `-#
} /dqKFxB1
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publicvoid setItems(List items){ ec=C7M
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this.items = items; I2dt#
} zM!*r~*k$
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publicint getPageSize(){ 7qk61YBLz
return pageSize; ?9mY #_Of
} ~$$V=$&
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publicvoid setPageSize(int pageSize){ p,+~dn;=
this.pageSize = pageSize; l>ttxYBa<d
} Qi%A/~
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publicint getTotalCount(){ t^'1Ebg
return totalCount; Uu(W62
} y^
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publicvoid setTotalCount(int totalCount){ !>tXib]:
if(totalCount > 0){ .^uu*S_
this.totalCount = totalCount; (<CLftQKg
int count = totalCount / ~(8A&!#,!
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.
pageSize; s|%</fMt9
if(totalCount % pageSize > 0) SnqLF
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count++; Cur)|
indexes = newint[count]; 01Aa.i^d(
for(int i = 0; i < count; i++){ s{/nO)
indexes = pageSize * U:>O6"
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} _D:/?=y;e
}else{ 5v3B8 @CsA
this.totalCount = 0; n RGH58
} ^vPa{+N
} f6XWA_[i@
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publicint[] getIndexes(){ &ke4":7X
return indexes; ";~#epPkX
} /[q@=X&
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publicvoid setIndexes(int[] indexes){ l^_X?L@
this.indexes = indexes; g41LpplX
} f,1rmX1
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publicint getStartIndex(){ ZoUfQ!2*
return startIndex; l|K8+5L
} ei5 S <n
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publicvoid setStartIndex(int startIndex){ GgtL./m
if(totalCount <= 0) WO{N@f^
this.startIndex = 0; wFvilF
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elseif(startIndex >= totalCount) +k>v^sz
this.startIndex = indexes 84{<]y
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[indexes.length - 1]; UY+~xzm
elseif(startIndex < 0) /b*@dy
this.startIndex = 0; kC+A7k6
else{ X;1q1X)K
this.startIndex = indexes ;2iZX=P`n
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[startIndex / pageSize]; IV*}w"r
} L?P8/]DGp
} Zy#r<j]T
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publicint getNextIndex(){ Li'T{0)1)
int nextIndex = getStartIndex() + f 6q@
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pageSize; !y),| #7P
if(nextIndex >= totalCount) %:y-"m1\u$
return getStartIndex(); YMWy5 \
else h {m]n!
return nextIndex; YT_kMy>
} &F:7U!
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publicint getPreviousIndex(){ gR6:J
int previousIndex = getStartIndex() - %*uqtw8
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pageSize; HGKm?'['
if(previousIndex < 0) ;gc2vDMv
return0; o
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else +n:#Uf)
return previousIndex; M}c_KFMV
} ?>&8,p17
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} oqE
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抽象业务类 +vuW9
java代码: lz( 9pz
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/** :G-1VtE n
* Created on 2005-7-12 JdAjKN
*/ X bg7mj9c
package com.javaeye.common.business; &Jn%2[;
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import java.io.Serializable; YlA=?
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import java.util.List; Bm?Ku7}.
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import org.hibernate.Criteria; +]{X-R
import org.hibernate.HibernateException; C
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import org.hibernate.Session; ZDb`]c4(
import org.hibernate.criterion.DetachedCriteria; $?A]!Y;
import org.hibernate.criterion.Projections; ufo?ZFq@$L
import 'ZJ6p0
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org.springframework.orm.hibernate3.HibernateCallback; <(iOzn
import #:yZJS9f9
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org.springframework.orm.hibernate3.support.HibernateDaoS <@yyx7
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upport; ~\^8
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import com.javaeye.common.util.PaginationSupport; itvwmI,m\
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public abstract class AbstractManager extends *Dn{MD7,M
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HibernateDaoSupport { sPw(+m*C
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privateboolean cacheQueries = false; ^KlOD_GN|
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privateString queryCacheRegion; /t/q$X
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publicvoid setCacheQueries(boolean fx|9*|E
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cacheQueries){ -Av/L>TxlI
this.cacheQueries = cacheQueries; kb6v2 ^8H
} Yv;aQF"a
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publicvoid setQueryCacheRegion(String [ M'1aBx^
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queryCacheRegion){ u>E+HxUJ
this.queryCacheRegion = &yN<@.
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queryCacheRegion; I|M*yObl6
} pr?/rXw
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publicvoid save(finalObject entity){ ]+Vcu zq/
getHibernateTemplate().save(entity); Pv'x|p*
} 3l^pY18H'
; YRZg|Zw
publicvoid persist(finalObject entity){ k (R4-"@
getHibernateTemplate().save(entity); `MD/CFl4
} Fzu{,b
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publicvoid update(finalObject entity){ !d^`YEfE
getHibernateTemplate().update(entity); PTP2QAt
} t|q=NK/
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publicvoid delete(finalObject entity){ Ysu/7o4
getHibernateTemplate().delete(entity); D,a%Je-r,
} 7w, FA
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publicObject load(finalClass entity, yxbTcZ
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finalSerializable id){ k#xpY!'7
return getHibernateTemplate().load #9OP.4
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(entity, id); N &=2 /
} _+iz?|U
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publicObject get(finalClass entity, fx:KH:q3
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finalSerializable id){ ,~(}lvqVH
return getHibernateTemplate().get $:!T/*p*
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(entity, id); zi
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} oE1]vX
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publicList findAll(finalClass entity){ *(B[J
return getHibernateTemplate().find("from "|`9{/]
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" + entity.getName());
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} RI3{>|*
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publicList findByNamedQuery(finalString 4&hqeY3
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namedQuery){ \/'n[3x
return getHibernateTemplate CL :M>(
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().findByNamedQuery(namedQuery); _x6E_i-(
} k=2l9C3Z
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publicList findByNamedQuery(finalString query, A5<Z&Y[
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finalObject parameter){ ZM`P~N1?)g
return getHibernateTemplate A>%UYA
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().findByNamedQuery(query, parameter); l~TIFmHkh%
} \Rqh|T<D
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publicList findByNamedQuery(finalString query, p6*a1^lU6
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finalObject[] parameters){ Cmx2/N
return getHibernateTemplate m_02"'
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().findByNamedQuery(query, parameters); f\_!N
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} vLFaZ^(
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publicList find(finalString query){ 'ag6B(0Z
return getHibernateTemplate().find :#:O(K1PW
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(query); qL5#.bR
} :8Ts'OGwI
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publicList find(finalString query, finalObject
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parameter){ P,;b'-5C
return getHibernateTemplate().find JRjMt-7H_
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(query, parameter); 1;:t~Y
} 4IP\iw#w
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public PaginationSupport findPageByCriteria >+jbMAYSq
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(final DetachedCriteria detachedCriteria){ RJ}yf|d-C
return findPageByCriteria M`+e'vdw
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 0I>?_?~l6
} c."bTq4tJ
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public PaginationSupport findPageByCriteria ;;w6b:}-c
@>#{WI:"~
(final DetachedCriteria detachedCriteria, finalint ]Z$TzT&@%
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startIndex){ vJj:9KcP>h
return findPageByCriteria aEEz4,x_
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(detachedCriteria, PaginationSupport.PAGESIZE, 9!xD~(Kr
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startIndex); [}p
} x ?f0Hk+
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public PaginationSupport findPageByCriteria .YjrV+om1
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(final DetachedCriteria detachedCriteria, finalint AFINm%\/0
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pageSize, Z[})40[M
finalint startIndex){ z{`6#
return(PaginationSupport) e+F}9HR7
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getHibernateTemplate().execute(new HibernateCallback(){ )RA\kZ "
publicObject doInHibernate rb *C-NutE
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(Session session)throws HibernateException { 1!>bhH}{D
Criteria criteria = SaR}\Up
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detachedCriteria.getExecutableCriteria(session); %="~\1y
int totalCount = YeRcf`
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((Integer) criteria.setProjection(Projections.rowCount k1f3?l
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()).uniqueResult()).intValue(); QmH/yy3.%
criteria.setProjection 4Q$j]U&b
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(null); iO%Zd[
List items = I%;Rn:zl
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criteria.setFirstResult(startIndex).setMaxResults :S QDqG
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(pageSize).list(); ERp:EZ'
PaginationSupport ps = $kxu;I
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new PaginationSupport(items, totalCount, pageSize, $xRo<,OV+
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startIndex); \3t,|%v
return ps; QO5OnYh
} _L*f8e8
}, true); PU^[HC*K
} SW,q}-
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public List findAllByCriteria(final =gW"#ZjL){
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DetachedCriteria detachedCriteria){ u{g]gA8s
return(List) getHibernateTemplate 5*JV )[
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().execute(new HibernateCallback(){ Jq#[uX
publicObject doInHibernate dzgs%qtK
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(Session session)throws HibernateException { #C"7
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Criteria criteria = H,(F1+~d
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detachedCriteria.getExecutableCriteria(session); a4yOe*Ak,F
return criteria.list(); c *.G]nRc
} k!Vn4?B"k
}, true); Q8 -3RgAw
} ,"@w>WL<9
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public int getCountByCriteria(final I") H~
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DetachedCriteria detachedCriteria){ `ifb<T
Integer count = (Integer) d-hbvLn
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getHibernateTemplate().execute(new HibernateCallback(){ Bp&6x;MJf
publicObject doInHibernate zXQVUhL6
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(Session session)throws HibernateException { ktN%!Mh\
Criteria criteria = $=\d1%_R|
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detachedCriteria.getExecutableCriteria(session); A)OdQFet(
return D._{E*vg
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criteria.setProjection(Projections.rowCount \^yXc*C
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()).uniqueResult(); '^hsH1
} *:?QB8YJ
}, true); -y%QRO(
return count.intValue(); j0AwL7
} <sa #|Y$
} ]GcV0&|
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用户在web层构造查询条件detachedCriteria,和可选的 :*=Ns[Y
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 @]*[c})/
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PaginationSupport的实例ps。 3] N q@t
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ps.getItems()得到已分页好的结果集 gglf\)E;}E
ps.getIndexes()得到分页索引的数组 (/-lV&eR
ps.getTotalCount()得到总结果数 ;"D~W#0-v
ps.getStartIndex()当前分页索引 b)d^ `J
ps.getNextIndex()下一页索引 B`#*o<eb
ps.getPreviousIndex()上一页索引 2_wvC
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }4Zkf<#7$
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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 5lGQ#r
7"#f!.E
一下代码重构了。 d)\2U{
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我把原本我的做法也提供出来供大家讨论吧: W-1sU g[AN
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首先,为了实现分页查询,我封装了一个Page类: 55^tfu
java代码: W8y$Ve8m
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/*Created on 2005-4-14*/ 6s5yyy=L%~
package org.flyware.util.page; +^Fp&K+^
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/** ;>8kPG
* @author Joa #,TELzUVE
* X~Cq
*/ /p,{?~0mj
publicclass Page {
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0t+])>
/** imply if the page has previous page */ 7|Xe&o<n
privateboolean hasPrePage; p3 e|j
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/** imply if the page has next page */ _H8*ReFG
privateboolean hasNextPage; Zb"jB$58
0iV;g`%
/** the number of every page */ Yh$fQ:yi\&
privateint everyPage; drI\iae{^
<*_o0;h|
/** the total page number */ d+0^u(gc!8
privateint totalPage; nZxSMN0]
&8n?
/** the number of current page */ ?~Pv3'%d
privateint currentPage; Y([d;_#P
-R :X<eb
/** the begin index of the records by the current "b`7[ ;a
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query */ &atyDFJ'
privateint beginIndex; Q(e{~
]*
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/** The default constructor */ eVx~n(m!}
public Page(){ -x{&an=
6A?8tm/0
} F\-Si!~oOz
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/** construct the page by everyPage hl<y4y&|
* @param everyPage r%|A$=[Q
* */ xG1?F_]
public Page(int everyPage){ I|T7+{5z
this.everyPage = everyPage; l!:^6i
} cJ2PI
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/** The whole constructor */ 0<Q*7aY
public Page(boolean hasPrePage, boolean hasNextPage, )b0];&hw]
7h`^N5H.q
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int everyPage, int totalPage, `;cz;"
int currentPage, int beginIndex){ :3O5ET'1
this.hasPrePage = hasPrePage; KUFz:&wK
this.hasNextPage = hasNextPage; G|*G9nQ
this.everyPage = everyPage; 1O0X-C,wo$
this.totalPage = totalPage; bb1f/C%
this.currentPage = currentPage; |z*>ixK
this.beginIndex = beginIndex; #x)8f3I
} (hN?:q?'
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/** Ha)np
* @return =k_UjwgN^
* Returns the beginIndex. r^5jh1
*/ \<V)-eB
publicint getBeginIndex(){ En\Z#0,V
return beginIndex; P0 b4Hq3
} ({ k7#1
h8
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/** (A4&k{C_
* @param beginIndex P,ydt
* The beginIndex to set. ^V.'^=l
*/ h/?6=D{
publicvoid setBeginIndex(int beginIndex){ SY T$3|a
this.beginIndex = beginIndex; ;MPKJS68@
} 9go))&`PJL
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/** CmnHh~%
* @return F>-}*o
* Returns the currentPage. m#n]Wgp'
*/ J^:n* C
publicint getCurrentPage(){ M4:s;@qZ.
return currentPage; ~},W8\C>
} ,Xtj;@~-
#&BS
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/** 8UM0vNk
* @param currentPage X~L!e}Rz
* The currentPage to set. U&W"Ea=R/
*/ sLhDO'kM
publicvoid setCurrentPage(int currentPage){ D/:3RZF
this.currentPage = currentPage; EO:avH.*0
} MI*Sq\-i
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/** "
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* @return 'RLOV
* Returns the everyPage. 0Oap39
*/ ti2
publicint getEveryPage(){ ^P$7A]!
return everyPage; A ~&+F>Z
} "~\*If
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/** {7X~!e|w
* @param everyPage S>t>6&A
* The everyPage to set. GFL-.?
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*/ <\aU"_D
publicvoid setEveryPage(int everyPage){ zy>}L #
this.everyPage = everyPage; l$M +.GB<
} "b%FmM
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/** ]sL45k2W
* @return zP nC=h|g
* Returns the hasNextPage. D=&K&6rr
*/ 2f..sNz
publicboolean getHasNextPage(){ '5rUe\k
return hasNextPage; Le@?
/
}
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/** ^73=7PZ
* @param hasNextPage T4GW1NP
* The hasNextPage to set. &J(!8y*QyE
*/ !G+u j(
publicvoid setHasNextPage(boolean hasNextPage){ <[hz?:G"$
this.hasNextPage = hasNextPage; ny1 \4C
} &HL{LnLP@/
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/** j04/[V)
* @return w+_Wc~f
* Returns the hasPrePage. 7#pZa.B)k
*/ Funj!x'uE
publicboolean getHasPrePage(){ j@ v-|
return hasPrePage;
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} p;`N\.ld
' ^a!`"Bc
/** ;rHz;]si
* @param hasPrePage /b{HG7i\
* The hasPrePage to set. /aOlYqM(>
*/ C +@ i
publicvoid setHasPrePage(boolean hasPrePage){ fSI %c3
this.hasPrePage = hasPrePage; * nCx[
} I?M@5u
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/** x+^Vg3 q
* @return Returns the totalPage. 4_Y!el H)
* 5;Ia$lm=y
*/ %6i=lyH-
publicint getTotalPage(){ `~nCbUUee
return totalPage; =]b9X7}
} gZ` DT
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/** |Fp'/~|w2d
* @param totalPage wd+O5Lr.R
* The totalPage to set. .bfST.OA
*/ H,|YLKg-|
publicvoid setTotalPage(int totalPage){ 4z0L ke
this.totalPage = totalPage; 2.qpt'p[
} >{XScxaB`
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} e1^l.>2d6
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 s=U\_koyH
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个PageUtil,负责对Page对象进行构造: [YE?OQ7#
java代码: FL&dv
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/*Created on 2005-4-14*/ a}yR p
package org.flyware.util.page; VDn:SGj5
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import org.apache.commons.logging.Log; <kbnu7?a*
import org.apache.commons.logging.LogFactory; q+%!<]7X
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/** b1)\Zi
* @author Joa v,0<9!'v
* 7d9Z/J@>
*/ /7vE>mSY
publicclass PageUtil { 0WXVc
**HrWM%?8o
privatestaticfinal Log logger = LogFactory.getLog !NA`g7'
6t$N78U
(PageUtil.class); .vaJ Avg
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/** NWnWk
* Use the origin page to create a new page U8[Qw}T P
* @param page eJaUmK:
* @param totalRecords dEET}s\
* @return Gh+f1)\FA"
*/ a7*COh
publicstatic Page createPage(Page page, int xB,/dMdTj
Hz? ,#>{
totalRecords){
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return createPage(page.getEveryPage(), 8_X.c
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page.getCurrentPage(), totalRecords); ~'{VaYk]v
} |0]YA
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/**
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* the basic page utils not including exception RNe9h lr
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handler Z9f/-|r5
* @param everyPage h[y*CzG
* @param currentPage xD^wTtT
* @param totalRecords v^\JWPR/
* @return page PJ;.31u
*/ O!,Ca1N
publicstatic Page createPage(int everyPage, int 1yJ75/
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currentPage, int totalRecords){ yWmrdvL
everyPage = getEveryPage(everyPage); R`
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currentPage = getCurrentPage(currentPage); sX!3_'-
int beginIndex = getBeginIndex(everyPage, y:C)%cv}*
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currentPage); 6N?#b66
int totalPage = getTotalPage(everyPage, {dBB{.hX
"R8.P/ 3
totalRecords); ?0uOR*y'
boolean hasNextPage = hasNextPage(currentPage, re/xs~
dB@FI
totalPage); L7<+LA)s0
boolean hasPrePage = hasPrePage(currentPage); r:73uRk
]~'9
returnnew Page(hasPrePage, hasNextPage, blUY.{NN3
everyPage, totalPage, {N"*olx
currentPage, ;}UzJe ,S
3hH>U%`-
beginIndex); t@6w$5:}
} ygMd$0:MN
:Jm!=U%'Z
privatestaticint getEveryPage(int everyPage){ ma1(EJ/
return everyPage == 0 ? 10 : everyPage; ]W+)ee|D
} ?THa5%8f
,}u,)7
privatestaticint getCurrentPage(int currentPage){ 0u>yT?jP
return currentPage == 0 ? 1 : currentPage; X=JFWzC
} (X*'y*:
' 4,y
privatestaticint getBeginIndex(int everyPage, int xm^N8
) sRN!~
currentPage){ RXUA!=e
return(currentPage - 1) * everyPage; Ywmyr[Uh'
} lK "'nLL
3xP~~j;7
privatestaticint getTotalPage(int everyPage, int mZ]P[lQ'5
@51z-T
totalRecords){ N`f!D>b:dn
int totalPage = 0; U[IQ1AEr
h>~jQ&\M
if(totalRecords % everyPage == 0) [+y&HNf
totalPage = totalRecords / everyPage; L^6"'#
else UVz=QEuYb
totalPage = totalRecords / everyPage + 1 ; VIb;96$Or
,?Ok[G!cm
return totalPage; H3!,d`D.N
} jMTRcj];(
cZ6?P`X
privatestaticboolean hasPrePage(int currentPage){ <_=JMA5
return currentPage == 1 ? false : true; ,;9ak-$8p
} |Uc<;> l
B.V?s,U
privatestaticboolean hasNextPage(int currentPage, ^cB49s+{e
th5
X?so
int totalPage){ u9esdOv
return currentPage == totalPage || totalPage == c]GQU
$$k7_rs
0 ? false : true; &/ \O2Aw8
} >Kz_My9
iU.!oeR?
976E3u"Vt
} >_rzT9gX&
eL<m.06cfY
es.jh
;7;zhJs1t
U*
-% M
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。 ,Y`'myL8W
<]Ij(+J;
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 7xX;MB&
|E46vup
做法如下: ^`l"'6
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 N7d17c.
5
OAmES;Ck$(
的信息,和一个结果集List: j9{O0[v
java代码: jjJc1 p0
MDMtOfe|
Dm7Y#)%8
/*Created on 2005-6-13*/ .}IK}A/-
package com.adt.bo; ;b, -$A
Nr>c'TH
import java.util.List; 1~["{u
uPa/,"p
import org.flyware.util.page.Page; yd7lcb
[
Xjs21-t%
/** v p"%IW
* @author Joa o?:;8]sr!
*/ cpE25
publicclass Result { Q%M'[L?[
y#hga5
private Page page; i_j9/k
8[6ny=S`
private List content; w$w>N(e
XNc"kp? z
/** Q'n(^tbL
* The default constructor /#S4espE
*/ tIz<+T_
public Result(){ -X"5G
super(); \zk?$'d
} 8m#}S\m
P<j4\zJ
/** 0EL\Hd
* The constructor using fields p)?qJ2c|
* m#5|J@]
* @param page .ujs`9d_-
* @param content (SgEt
*/ O,F]\
public Result(Page page, List content){ K;@RUy~
this.page = page; yj}bY?4I
this.content = content; ]jVIpGM
} VxUvvJ{-v
kPx]u\
/** @Og\SZhn
* @return Returns the content. ?$"x^=te7
*/ kjLsk-
publicList getContent(){ d-6sC@PB
return content; #}[Sj-Vp
} x'E'jh%
aJuj7y-
/** d&PE,$XC
* @return Returns the page. ?V&Ld$db
*/ w6WGFQ_ %
public Page getPage(){ h/0<:eZ*
return page; Mr5('9%
} jQ.>2-;H9
"K}W^J9v
/** &.cGj@1!J
* @param content [M7iJcwt
* The content to set. ?MV[=LPL
*/ h3UZ|B0=
public void setContent(List content){ j:rs+1bc
this.content = content; ;w>3,ub(0
} t7C!}'g&'
eeI9[lTw
/** U(S@1i(
* @param page _g^K$+F'}
* The page to set.
m+72C]9
*/ 7.lK$J:
publicvoid setPage(Page page){ z. _C*c
this.page = page; G:h;C].
} %9~kA5Qj
} ??$i*
)9A<fwpN
.v
#0cQX+.
dN$D6*
0]:*v?
2. 编写业务逻辑接口,并实现它(UserManager, &;NNUT>Q
W[[YOK1T
UserManagerImpl) Gg}LC+Y
java代码: Pjj;.c 7_j
Y-neD?V N
JL]k:i^`A
/*Created on 2005-7-15*/ ^V XXq
package com.adt.service; 32iWYN
a!^-~pH:
import net.sf.hibernate.HibernateException; (_%JF[W
(<>Sz(
import org.flyware.util.page.Page; eBSn1n
Ol/2%UJXL
import com.adt.bo.Result; IJ
#v"! D
Vne.HFXA
/** v:J.d5
* @author Joa st'?3A
*/ -pU\"$nuxH
publicinterface UserManager { I).^,%>Z)
YV ZSKU
public Result listUser(Page page)throws g`~lIt[=
My6]k?;}(
HibernateException; (7Ca\H3$
6M<mOhp@}n
}
6>N u=~
qed!C
#r:Kg&W2FO
*Y^Y
!+*?pq
java代码: M*T# 5
2fL88/'
7z P
/*Created on 2005-7-15*/ p-(ADQS
package com.adt.service.impl; 9V4V}[%
'bY|$\I
import java.util.List; @R-~zOv
@x-GbK?
import net.sf.hibernate.HibernateException; n
nnA,
Kj<<&_B.H
import org.flyware.util.page.Page; B,VSFpPx
import org.flyware.util.page.PageUtil; gx>mKSzy
f@.Q%+!4
import com.adt.bo.Result; GE3U0w6WbK
import com.adt.dao.UserDAO; Bdk{.oh6
import com.adt.exception.ObjectNotFoundException; 5@&i:vs5y
import com.adt.service.UserManager; OHtZ"^YG
YT 03>!B
/** ~E6+2t*
* @author Joa ``YL]
<<
*/ ;|$]Qq
publicclass UserManagerImpl implements UserManager { /jL{JF>I
XY t8vJ
private UserDAO userDAO; CR<pB)F?a
!\k#{
1[!
/** ]#7Y@Yo
* @param userDAO The userDAO to set. W 9:{pQG
*/ w-Q 6
-
publicvoid setUserDAO(UserDAO userDAO){ ^CZ|ci6bX
this.userDAO = userDAO; N n-6/]d#
} ?28GQyk4
+fQ$~vr{'
/* (non-Javadoc) <!HDtN
* @see com.adt.service.UserManager#listUser 0@/E%T1c"
:)V0zHo&(
(org.flyware.util.page.Page) |(w#NE5
*/ c"&!=@
public Result listUser(Page page)throws 8RT0&[
Qc<O; #
HibernateException, ObjectNotFoundException { U
&k3
int totalRecords = userDAO.getUserCount(); K[;,/:Y
if(totalRecords == 0) |/Q. "d
throw new ObjectNotFoundException {kO:HhUg
Q+js2?7^
("userNotExist"); F4{. 7BT
page = PageUtil.createPage(page, totalRecords); $mg h.3z0
List users = userDAO.getUserByPage(page); l#f]KLv4N_
returnnew Result(page, users); a|{<#<6n(
} "uERa(i
..{^"`FQ
} 5<8>G?Y
_q4dgi z
:<3;7R'5
!Kqj&y5
N<r0I-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ZrT|~$*m`
soK_l|z:J
询,接下来编写UserDAO的代码: U5%]nT"[]
3. UserDAO 和 UserDAOImpl: mNB ]e5;N
java代码: Y$5v3E\uc
]1$AAmQH
p.Yg-CA
/*Created on 2005-7-15*/ KEB>}_[
package com.adt.dao; c)~|#v
X"59`Yh
import java.util.List; d"uM7PMs7x
T<,tC"
import org.flyware.util.page.Page; ,(?4T~
U.} =j'Us+
import net.sf.hibernate.HibernateException; 5W'|qmJ
j0NPd^
/** GB Un" _J
* @author Joa l_IX+4(@b|
*/ [<Puh
publicinterface UserDAO extends BaseDAO { 5 :>
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publicList getUserByName(String name)throws 'B:De"_(N
&,|uTIs
HibernateException; I4ct``Di
,fLe%RP
publicint getUserCount()throws HibernateException; \K=PIcH
~&|i'f[
publicList getUserByPage(Page page)throws ~u1JR`y
Y0'^S<ox
HibernateException; LM`#S/h
}+3~y'k
} 6%axbB
v65r@)\`
j0M;2 3@[
c(JO;=,@9
2M`Ni&v
java代码: 7:<>#
l/M+JT~R
.l'QCW9
/*Created on 2005-7-15*/ x&p=vUuukP
package com.adt.dao.impl; (#BA{9T,^
3F3?be
import java.util.List; 3".W
|a3b2x,
import org.flyware.util.page.Page; sIM`Q%
1yf&ck1R
import net.sf.hibernate.HibernateException; u^9,u/gj
import net.sf.hibernate.Query; ymqhI\>y#
Vngi8%YWp
import com.adt.dao.UserDAO; 4QDzG~N4)|
O#k+.LU
/** ?whp_
* @author Joa dD!SgK [Jv
*/ 3e:y?hpeL
public class UserDAOImpl extends BaseDAOHibernateImpl ]|(?i ,p
U[u6UG
implements UserDAO { U)6JJv
W3kilhZ
/* (non-Javadoc) a WC
sLH
* @see com.adt.dao.UserDAO#getUserByName To95WG7G
kE}Ib4]J
(java.lang.String) V00zk`PH
*/ b1"wQM9
publicList getUserByName(String name)throws <Do89
7va%-&.&t
HibernateException { Z )I4U
String querySentence = "FROM user in class Q=E6ZxH5;
~Fh(4'
com.adt.po.User WHERE user.name=:name"; Urr1K)
Query query = getSession().createQuery &/"
qOZAs
t!$/r]XM h
(querySentence); 2J5dZYW
query.setParameter("name", name); *@Z'{V\
return query.list(); aJts
} &-9D.'WzP
bBf+z7iyc
/* (non-Javadoc) 1zffPC8jl
* @see com.adt.dao.UserDAO#getUserCount() !.A>)+AK
*/ +J}M$eQ
publicint getUserCount()throws HibernateException { Y;WrfO$J
int count = 0; rv[\2@}
String querySentence = "SELECT count(*) FROM l%O-c}X
gkjZX
wp
user in class com.adt.po.User"; =G`m7!Q)
Query query = getSession().createQuery }\ F>z
)_ y{^kn3^
(querySentence); VI4d/2e
count = ((Integer)query.iterate().next OkM>
??Lxb% 7R
()).intValue(); Z'~5L_.]Ai
return count; =W6P>r_
} {+ m)*3~w
UTz;Sw?~hw
/* (non-Javadoc) BdTj0{S1u
* @see com.adt.dao.UserDAO#getUserByPage sC$X7h(Q+
:5(TOF
(org.flyware.util.page.Page) (0S"ZT
*/ >3JOQ;:d8
publicList getUserByPage(Page page)throws `i}\k
6\`,blkX
HibernateException { otOl7XF
String querySentence = "FROM user in class +1Uw <~
hN.#ui5 $
com.adt.po.User"; rtI4W
Query query = getSession().createQuery z<ek?0?yS
_R]1J0
(querySentence); SOm~];[
query.setFirstResult(page.getBeginIndex()) &45.*l|mo
.setMaxResults(page.getEveryPage()); 1Dbe0u
return query.list(); HTC7fS
} P
_ SJK
lIf Our
} k;)L-ge9
6l=n&YO
$6_J`7
@U&|38
`s+qz
至此,一个完整的分页程序完成。前台的只需要调用 6Hz=VhQrN
2XE4w# [j
userManager.listUser(page)即可得到一个Page对象和结果集对象 9SrV,~zD
`@ObM[0p(
的综合体,而传入的参数page对象则可以由前台传入,如果用 @=9QV3D
:{sX8U%
webwork,甚至可以直接在配置文件中指定。 DCNuvrZ
wiutUb
Y
下面给出一个webwork调用示例: jj^CW"IB
java代码: N>/U%01a
2]7nw1&
29E^]IL?
/*Created on 2005-6-17*/ }/=VnCfU
package com.adt.action.user; <%!@cE+y
/q> "">
import java.util.List; cgU7)`0j
67#;.}4a
import org.apache.commons.logging.Log; 55#H A?cR
import org.apache.commons.logging.LogFactory; ci$o~b6V
import org.flyware.util.page.Page; ]-O:| q>]
vX{]_
import com.adt.bo.Result; iQA
f
import com.adt.service.UserService; 2nwP-i
import com.opensymphony.xwork.Action; -O ej6sILO
kY*D s;
/** iR_X,&p
* @author Joa nTLdknh"
*/ /{Nx%PqL
publicclass ListUser implementsAction{ #"TTI
vd0
S3 &L
privatestaticfinal Log logger = LogFactory.getLog ~*H!zKIx
D@!#79:)
(ListUser.class); rHP5;j<]
7^ER?@:W
private UserService userService; "6.kZ$`%
D].1X0^hp
private Page page; O7E0{8
JD,/oL.KA
privateList users; Ru2kC} Dx!
Z5+qb
/* <zrGPwk
* (non-Javadoc) o@"H3
gz
* :dB6/@fW
* @see com.opensymphony.xwork.Action#execute()
d':c
*/ @'dtlY5;
publicString execute()throwsException{ c\7~_w2
Result result = userService.listUser(page); @<;0h|
page = result.getPage(); $O=m/l$
users = result.getContent(); 85-00m ~
return SUCCESS; /JJU-A(
} E7ixl~
@=:( b"Sg
/** z^@98:x
* @return Returns the page. aO6w:IO
*/ r;SA1n#
public Page getPage(){ )nQA) uz
return page; O\8_;Gc;
} r,a V11{
UhXZ^k3
/** }GRZCX>
* @return Returns the users. 8 Zhx&
*/ :OQx;>'
publicList getUsers(){ #[ipJ %
return users; c/%i,N\5
} 9Eu.Y
bC&*U|de
/** ?%(:
* @param page #+>8gq^5
* The page to set. ~QQi{92
*/ G&y< lh
publicvoid setPage(Page page){ {d|e@`"T
this.page = page; ^Q0%_V,
} ;Hk{bz(
lpi^<LQ@l
/** * `1W})
* @param users dn!#c=
* The users to set. u?,M`w0'
*/ }V:ZGP#!'
publicvoid setUsers(List users){ js^+ {~
this.users = users; V $Y=JK@
} ]6#bp,
41dB4Td5t
/** G6@XRib3
* @param userService X?kw=x{2P
* The userService to set. 8=\}#F
*/ m?*}yM
publicvoid setUserService(UserService userService){ }JPLhr|d^
this.userService = userService; F/.nr
} jjLx60|{
} RKru
hF
3}hJ`xQ
jAXKp
b
Q &~|P}
$DS|jnpV
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, dA03,s
T%q@jv{c
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 P-]u&m/6
VCf/EkC
么只需要: x#)CH}J
java代码: r8%"#<]/
n[+$a)$8
}%)]b*3
<?xml version="1.0"?> }o,-@R~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork g$S|CqRG
Bl$Hg,in-
1.0//EN" "http://www.opensymphony.com/xwork/xwork- dQ#$(<v[
C"7-lz
1.0.dtd"> T@H<Fm_
FHOF6}if
<xwork> H"5=z7w
^L?2y/
<package name="user" extends="webwork- !
mb<z^>5
IEmjWw4
interceptors"> 9Ib#A
y
<] x
<!-- The default interceptor stack name W#Eg\nT
"rVf{
--> Gov]^?^D-
<default-interceptor-ref 3q-Xj:FP
ZVIlVuZ}
name="myDefaultWebStack"/> Qo\+FkhYq
(/$a*$
<action name="listUser" i K,^|Q8
lY$9-Q(
class="com.adt.action.user.ListUser"> JavSR1_
<param nq%GLUH
B>r>z5
name="page.everyPage">10</param> 6<SX%Bc~
<result
JRr'81\
e|
Sw+fhy<
name="success">/user/user_list.jsp</result> | K w}S/F
</action> >Q#\X=a>
"30R%oL]=
</package> _z6 " C8W
~0V,B1a
</xwork> #-7w|
HDQH7Bs
`xsU'Wd^<
]I:h4hgw
WfH4*e
hZtJ LY
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 (5h+b_eB
?4sF:Y+\
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 w,VUWja
x.%x|6G*
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ^oXLk&d
q[5&
Bhf4 /$
d9pZg=$8
~#PC(g
我写的一个用于分页的类,用了泛型了,hoho a&C}'e"
#,;X2% c
java代码: ;@s'JSPt
9-hVlQ~|
VWT\wAL
package com.intokr.util; `3'4_@7s9
#G\;)pT
import java.util.List; 0u=FlQ
}h
~9JLqN"
/** Dl=qss~g+
* 用于分页的类<br> '[`pU>9
* 可以用于传递查询的结果也可以用于传送查询的参数<br> IgNL1KRD
* 2>'/!/+R
* @version 0.01 {hi'LA-4@
* @author cheng <~iA{sY)O
*/ Av,E|C
public class Paginator<E> { m$H(l4wB>
privateint count = 0; // 总记录数 n+H);Dg<8
privateint p = 1; // 页编号 :M9 E
privateint num = 20; // 每页的记录数 C,G$C7$%
privateList<E> results = null; // 结果 Kn4x_9
69JC!du
/** S T25RJC
* 结果总数 +?y9EZB%
*/ BjAmM*k
publicint getCount(){ m8NKuhu
return count; Uv%?z0F<C
} [O\[,E"K
<p\iB'y
publicvoid setCount(int count){ D>m!R[!o
this.count = count; G;yh$n<"
} B,avI&7M;S
jLCZ
JSK
/** ylPDM7Ka
* 本结果所在的页码,从1开始 Ai 5|N
* " twq#Alx
* @return Returns the pageNo. > ?<C+ZHh
*/ _'"$,~ZWY
publicint getP(){ |nq}#
return p; WbH#@]+DN
} ).uR@j
*Rj(~Q/t
/** Nlk'
* if(p<=0) p=1 e{fm7Cc)D
* 3e7P
w`gLl
* @param p u!D AeE
*/ -$+`v<[r
publicvoid setP(int p){ GEQ3r'B|
if(p <= 0) -9> oB
p = 1; 9Bw.Ih[Z
this.p = p; C3z#A3&J
} lCC(N?%Q
Qz9*o
/** ^L +@oS
* 每页记录数量 3gNVnmZG
*/ uSU[Y,'x
publicint getNum(){ rA6lyzJ
return num; 9e>Dqlv
} \g<=n&S?
;8J+Q0V
/** b%"Lwqdr7
* if(num<1) num=1 W&Pp5KR
*/ lx"#S'^~
publicvoid setNum(int num){ $2lPUQZ<5
if(num < 1) 'mR9Uqq\
num = 1; 4 g}'/
this.num = num; -`<