Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 {@A2jk\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 6,PLzZ5
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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 7 SZR#L
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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 n&]w* (,
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分页支持类: [w f12P
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java代码: %*OJRL`
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package com.javaeye.common.util; 7Cf(y'w^
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import java.util.List; AHGcWS\,X
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publicclass PaginationSupport { #4M0%rN
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publicfinalstaticint PAGESIZE = 30; V{{x~Q9
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privateint pageSize = PAGESIZE; 3iw9jhK!W
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privateList items; Oe`t!&v
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privateint totalCount; ^%pwyY\t
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privateint[] indexes = newint[0]; [2V/v
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privateint startIndex = 0; 0
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public PaginationSupport(List items, int "[yiNJ"kt
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totalCount){ T"U t).
setPageSize(PAGESIZE); 8BDL{?Mu
setTotalCount(totalCount); Umg81!
setItems(items); WKsx|a]U
setStartIndex(0); n~j[Pw
} Sj?sw]3
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public PaginationSupport(List items, int <>s\tJ
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totalCount, int startIndex){ lvi:I+VgA
setPageSize(PAGESIZE); JB@VP{
setTotalCount(totalCount); U I C? S
setItems(items); "M^W:4_
setStartIndex(startIndex); DT4RodE$
} uszSFe]E
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public PaginationSupport(List items, int ^ {f^WL=
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totalCount, int pageSize, int startIndex){ 0(x@
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setPageSize(pageSize); -^v}T/Kl#
setTotalCount(totalCount); _#mqg]W '
setItems(items); bq-\'h
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setStartIndex(startIndex); :* b4/qpYv
} :g[x;Q[@
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publicList getItems(){ ~-wJ#E3g
return items; tL{~O=
} 0z7mre^Q
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publicvoid setItems(List items){ G6{A[O[
this.items = items; *J5RueUG
} |wQZ~Ux:
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publicint getPageSize(){ twmJ
return pageSize; n5*7~K"C
} a<TL&
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publicvoid setPageSize(int pageSize){ IQe[ CcM
this.pageSize = pageSize; :<k|u!b}y
} 'hw@l>1\9
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publicint getTotalCount(){ `e>F<{
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return totalCount; @n*D>g
} k=2l9C3Z
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publicvoid setTotalCount(int totalCount){ Gj`Y2X2r
if(totalCount > 0){ cE5Zxcn
this.totalCount = totalCount; ?^ezEpW
int count = totalCount / h./vTNMc
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pageSize; !r
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if(totalCount % pageSize > 0) )+4}Ix/q
count++; O) %kl
indexes = newint[count]; SoU'r]k1x
for(int i = 0; i < count; i++){ Pl&`&N;
indexes = pageSize * =v$s+`cP
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i; "UGj4^1f
} r5fkt>HZ
}else{ fhIj+/{_O
this.totalCount = 0; c_$&Uii
} p[F=L P
} Bye@5D
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publicint[] getIndexes(){ tW"ptU^9)
return indexes; k5QD5/Ej
} 'oZn<c`
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publicvoid setIndexes(int[] indexes){ ivz9R'
this.indexes = indexes; {-N90Oe
} <` j[;>O
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publicint getStartIndex(){ _% 9+U[@
return startIndex; ) v5n "W
} 7h9[-d6
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publicvoid setStartIndex(int startIndex){ [S&O-b8A
if(totalCount <= 0) fw v
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this.startIndex = 0; "Xk%3\{P
elseif(startIndex >= totalCount) +M
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this.startIndex = indexes J*~2:{=%
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[indexes.length - 1]; A='+tJa
elseif(startIndex < 0) Z F yX@#B9
this.startIndex = 0; *RbOQ86vP
else{ (&S[R{=^j
this.startIndex = indexes 4Re@ QOZ
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[startIndex / pageSize]; Jv^cOc
} G q:4rG|
} hf+/kc!>i
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publicint getNextIndex(){ Ms'TC;&PS
int nextIndex = getStartIndex() + 4IP\iw#w
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pageSize; /z)3gsF
if(nextIndex >= totalCount) r>:L$_]L
return getStartIndex(); U]! .~ji3
else xe gL!
return nextIndex; !E{GcK
} [zTYiNa
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publicint getPreviousIndex(){ 7hF,gl5
int previousIndex = getStartIndex() - u->@|tEq
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pageSize; g t^]32$
if(previousIndex < 0) yEpN,A
return0; $mI:Im`s
else ZA_zKJ[[7
return previousIndex; Y =g>r]2
} p17|ld`
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} [Zt#
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抽象业务类 cbh#E)['
java代码: @!":(@3[
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/** esh$*)1
* Created on 2005-7-12 ^Cc8F3os=
*/ A{4G@k+#d
package com.javaeye.common.business; LZUA+ x(
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import java.io.Serializable; ?z5ne??
import java.util.List; CQBT::
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import org.hibernate.Criteria; |{7e#ww]
import org.hibernate.HibernateException; ^sT+5M^
import org.hibernate.Session; ?#BZ `H
import org.hibernate.criterion.DetachedCriteria; JNxW6 cK
import org.hibernate.criterion.Projections; 2AXF$YjY
import Th7wP:iDP
~+pg^en
org.springframework.orm.hibernate3.HibernateCallback; H5AK n*'7
import Avs7(-L+s
8S.')<-f
org.springframework.orm.hibernate3.support.HibernateDaoS W+d9cM=
f.b8ZBNj>
upport; IOsXPf9@
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import com.javaeye.common.util.PaginationSupport; 670J{b
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public abstract class AbstractManager extends j*;*Ka w
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HibernateDaoSupport { m\*&2Na
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privateboolean cacheQueries = false; ``(}4a
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privateString queryCacheRegion; ;f".'9 l^
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publicvoid setCacheQueries(boolean Exep+x-
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cacheQueries){ '^Pq(b~
this.cacheQueries = cacheQueries; %PQldPL8
} u;+%Qh
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publicvoid setQueryCacheRegion(String $:f.Krj
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queryCacheRegion){ 6-*~t8
this.queryCacheRegion = O%YjWb
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queryCacheRegion; vQ:x%=]
} S}zC3
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publicvoid save(finalObject entity){ \3%W_vU_
getHibernateTemplate().save(entity); SW,q}-
} Hi]vHG(
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publicvoid persist(finalObject entity){ a);O3N/*I
getHibernateTemplate().save(entity); #2Ac
} H/^~<U#p
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publicvoid update(finalObject entity){ f*{M3"$E
getHibernateTemplate().update(entity); <)_:NRjBF&
} X!U]`Qh
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publicvoid delete(finalObject entity){ McT\ R{/
getHibernateTemplate().delete(entity); ky'|Wk6
} }7iUagN
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publicObject load(finalClass entity, ..??O^
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finalSerializable id){ fzLANya
return getHibernateTemplate().load ,]f) ,;=
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(entity, id); l*QIoRYFW
} - waX#UT=
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publicObject get(finalClass entity, xh{mca>?G
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finalSerializable id){ N1YgYL
return getHibernateTemplate().get )2)Zz +<
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(entity, id); NOF?LV
} @b]VCv0*f%
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publicList findAll(finalClass entity){ >oe4mW
return getHibernateTemplate().find("from w>v5oy8s-
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" + entity.getName()); >ysriPnQ
} .KFA218h*x
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publicList findByNamedQuery(finalString I_:t}3s
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namedQuery){ NU|qX {-
return getHibernateTemplate K1;zMh
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().findByNamedQuery(namedQuery); !-KCFMvT
} '!pAnsXfO
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publicList findByNamedQuery(finalString query, M,&tA1CH
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finalObject parameter){ cE^kpnVq|<
return getHibernateTemplate .H
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().findByNamedQuery(query, parameter); !K!)S^^Po?
} DD2adu^
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publicList findByNamedQuery(finalString query, \'[3^/('
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finalObject[] parameters){ Dp^"J85}
return getHibernateTemplate E
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().findByNamedQuery(query, parameters); 1JIG+ZN md
} }|AX_=a
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publicList find(finalString query){ |Es0[cU
return getHibernateTemplate().find U> W|(Y
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(query); =ntftSH
} j(&GVy^;?
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publicList find(finalString query, finalObject !zU/Hq{wcK
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parameter){ _jW>dU^B
return getHibernateTemplate().find 9p5= _
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(query, parameter); P%iP:16
} VXiui'/(
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public PaginationSupport findPageByCriteria '[%jjUU
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(final DetachedCriteria detachedCriteria){ CdZnD#F2
return findPageByCriteria >Dxe>Q'df
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); L"4]Tm>zq
} ;"D~W#0-v
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public PaginationSupport findPageByCriteria iZC>)&ax
]}.0el{
(final DetachedCriteria detachedCriteria, finalint 7vw;Egd@@-
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startIndex){ Cc2MYm8
return findPageByCriteria b(/j\NWC
[M`=HhJ4
(detachedCriteria, PaginationSupport.PAGESIZE, XJc
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startIndex); 2R\+}
} 7"#f!.E
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public PaginationSupport findPageByCriteria |88CBiu}
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(final DetachedCriteria detachedCriteria, finalint ubi~%
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pageSize, w;~>k%}j
finalint startIndex){ r|<6Aae&
return(PaginationSupport) r5[4h'f
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getHibernateTemplate().execute(new HibernateCallback(){ Nfg{,/O
publicObject doInHibernate c+~LpSQ
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(Session session)throws HibernateException { #,TELzUVE
Criteria criteria = 76_<xUt{
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detachedCriteria.getExecutableCriteria(session); Yc|uD-y
int totalCount = X{`1:c'x
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((Integer) criteria.setProjection(Projections.rowCount P8<hvMF
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()).uniqueResult()).intValue(); 5?w.rcN[j
criteria.setProjection RtwUb(wn6
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(null); "-P/jk
List items = <1K7@Tu
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criteria.setFirstResult(startIndex).setMaxResults `UQEXoB)
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(pageSize).list(); sCkO0dl8
PaginationSupport ps = (vnoP< 0
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new PaginationSupport(items, totalCount, pageSize, JYQ.EAsr!
"H$@b`)
startIndex); \ADLMj`F|
return ps; L:pUvcAc?
} O>%$q8x@i
}, true); ;
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} tvGlp)?.
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public List findAllByCriteria(final sBU_Ft
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DetachedCriteria detachedCriteria){ p31oL{D
return(List) getHibernateTemplate WFem#hq
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().execute(new HibernateCallback(){ 8ljuc5,J
publicObject doInHibernate uFo/s&6K
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(Session session)throws HibernateException { 2T?TM! \Q
Criteria criteria = zqf[Z3
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detachedCriteria.getExecutableCriteria(session); +?Ez}
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return criteria.list(); m8+:=0|$
} '60//"9>k/
}, true); `;cz;"
} :3O5ET'1
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public int getCountByCriteria(final ^BiPLQ
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DetachedCriteria detachedCriteria){ %J!NL0x_
Integer count = (Integer) ~)?|J
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getHibernateTemplate().execute(new HibernateCallback(){ c]NN'9G!{
publicObject doInHibernate 0m
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, D"]y~~I5
(Session session)throws HibernateException { WqQU@sA
Criteria criteria = #w|5jN?
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detachedCriteria.getExecutableCriteria(session); }LQC.!
return qnXTNs
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criteria.setProjection(Projections.rowCount n}q$f|4!
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()).uniqueResult(); uY]0dyI
} ?
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}, true); TF2KZL#A|
return count.intValue(); ve fU'
} n"Z |e tZ4
} Y{+3}drJE
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用户在web层构造查询条件detachedCriteria,和可选的 PIxjM>
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [0!{_E)<
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PaginationSupport的实例ps。 .&|L|q}
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ps.getItems()得到已分页好的结果集 <u0,Fp
ps.getIndexes()得到分页索引的数组 n[CoS
ps.getTotalCount()得到总结果数 M*`hDdS
ps.getStartIndex()当前分页索引 y/tSGkMv
ps.getNextIndex()下一页索引 $r15gfne>
ps.getPreviousIndex()上一页索引 F0.z i>5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 !8/gL
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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 &F6C
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一下代码重构了。 +|&0fGv;d9
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我把原本我的做法也提供出来供大家讨论吧: vyU!+mlc
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首先,为了实现分页查询,我封装了一个Page类: DFy1 bg
java代码: !_x*m@/
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/*Created on 2005-4-14*/ X<euD9?
package org.flyware.util.page; mb{q(WEPP
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/** ~ffwLgu!
* @author Joa Mudrg[@`
* JA6";fl;
*/ :<utq|#s
publicclass Page { IU9,
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/** imply if the page has previous page */ 1~Mn'O%
privateboolean hasPrePage; y6%<zhs
#PFO]j!_b
/** imply if the page has next page */ D^?_"wjW
privateboolean hasNextPage; MLS;SCl
u)~s4tP4
/** the number of every page */ 9rcI+q=E
privateint everyPage; sE9Ckc5
n)RM+g
/** the total page number */ BIfi:7I;Q
privateint totalPage; CDCC1B G"
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/** the number of current page */ ti9}*8
privateint currentPage; ;_tO+xL&
,8##OB(
/** the begin index of the records by the current DsQ/aG9c%
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query */ 4f {+pf^R
privateint beginIndex; c0[k T
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/** The default constructor */ AP w6
public Page(){ {ERjeuDm]
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} &t_h'JX&
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/** construct the page by everyPage (.Xr#;\(
* @param everyPage t)r1"oA
* */ D^$OCj\
public Page(int everyPage){ ? OsS`)T
this.everyPage = everyPage; y x;h
} X4Xf2aXI
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/** The whole constructor */ ?D=8{!R3
public Page(boolean hasPrePage, boolean hasNextPage, aYVDp{_
eq hAus?)
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int everyPage, int totalPage, ps+:</;Z
int currentPage, int beginIndex){ )4uq
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this.hasPrePage = hasPrePage; y<M]dd$
this.hasNextPage = hasNextPage; :hP58 }Q$
this.everyPage = everyPage; !01i%W'
this.totalPage = totalPage; h8.FX-0& =
this.currentPage = currentPage; eP= j.$
this.beginIndex = beginIndex; tcOnM w
} v}P!HczmMP
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/** 6LM9e0oxy
* @return 9v~5qv;
* Returns the beginIndex.
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*/ 61:9(*4~!F
publicint getBeginIndex(){ 40.AM1Z0f
return beginIndex; hdg<bZk:
} v[L[A3`"/
P)1EA;
/** ?Ib}
* @param beginIndex J]\^QMX
* The beginIndex to set. S@A<6
*/ or.\)(m#(
publicvoid setBeginIndex(int beginIndex){ 5"gL.Ez
this.beginIndex = beginIndex; 5^2TfG9
} bQ.nFa']
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/** e5OVq
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* @return *"T+G*~
* Returns the currentPage. {US>)I
*/ !*bdG(pK
publicint getCurrentPage(){ jw4TLc7p
return currentPage; OjATSmZ@@
} FmI;lVF0j
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/** 4 Py3I9
* @param currentPage D|TR!
* The currentPage to set. b1)\Zi
*/ veO?k.u(
publicvoid setCurrentPage(int currentPage){ Z =
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this.currentPage = currentPage; 61,O%lV
} O6]u!NqG
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/** gh61H:t kR
* @return <<<NXsH
* Returns the everyPage. pVz*ZQ[]
*/ PWG;&ma
publicint getEveryPage(){ 7LdzZS0OM
return everyPage; H:MUNc8i
} yHOqzq56
mu>] 9ZW
/** UR,?! rJ^B
* @param everyPage ^U{P3%uZ
* The everyPage to set. ;@4sd%L8V
*/ UN(3i(d
publicvoid setEveryPage(int everyPage){ A^L?_\e6
this.everyPage = everyPage; e^WqJ7j
} 5L3{w+V
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/** qK-qcPLsl
* @return L!vWRwZwC
* Returns the hasNextPage. W0?JVtq0Z
*/ |*1xrM:v~
publicboolean getHasNextPage(){ r\RFDj
return hasNextPage; >#?iO]).
} Om6Mmoqh
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/** k.Gl4
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* @param hasNextPage oX{@'B
* The hasNextPage to set. 9tAE#A
*/ B!iFmkCy
publicvoid setHasNextPage(boolean hasNextPage){ FE}s#n_Pd
this.hasNextPage = hasNextPage; kyu2)L2u
} !mae^A1
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/** q|Fjm]AF
* @return C (U
* Returns the hasPrePage. `GS cRhbh
*/ W1`Dx(g
publicboolean getHasPrePage(){ :mn(0
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return hasPrePage; pJocI_v9
} ->3uOF!q
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/** +K&?)?/=
* @param hasPrePage *?p
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* The hasPrePage to set. $r):d
*/ r;'i<t{P
publicvoid setHasPrePage(boolean hasPrePage){ bw020@O*
this.hasPrePage = hasPrePage; Z,SY
N?@
} (H2ylMpQt
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/** EoKo
* @return Returns the totalPage. LS{bg.e
* 0W_mCV
*/ X*)?LxTj
publicint getTotalPage(){ $8Ig&k|~8
return totalPage; d~sJ=)
} M6&~LI.We=
T:6K?$y?
/** P*7S3Td
* @param totalPage dB@FI
* The totalPage to set. X0!Bs-WFp
*/ Enu!u~1]F
publicvoid setTotalPage(int totalPage){ 'H!V54
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this.totalPage = totalPage; TqXge{r
} W oWBs)E
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*,0
} df^0{gNHx
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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 aDN.gMS
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个PageUtil,负责对Page对象进行构造: C/bxfp{?
java代码: B#QL M^
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/*Created on 2005-4-14*/ ma1(EJ/
package org.flyware.util.page; eVrnVPkM
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import org.apache.commons.logging.Log; Q*Y4m8wY
import org.apache.commons.logging.LogFactory; K[*h+YO
zUJx&5/
/** i},d[
* @author Joa ; 4l-M2
* fjcr<&{:
*/ Bpm,mp4g\#
publicclass PageUtil { 0e)lY='^_
}M^_Z#|,
privatestaticfinal Log logger = LogFactory.getLog xUQdVrFU
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(PageUtil.class); hI*`> 9l
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/** b/z'`?[
* Use the origin page to create a new page _a fciyso
* @param page y?"$(%3|
* @param totalRecords 4C6=77Jr
* @return )ni"qv~J
*/ 0T(O'v}.
publicstatic Page createPage(Page page, int E1#H{)G
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totalRecords){ N`f!D>b:dn
return createPage(page.getEveryPage(), Rq"VB.ef&{
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page.getCurrentPage(), totalRecords); 04P.p6
} $|rCrak;
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/** DE5d]3B
* the basic page utils not including exception z'?SRK5+
kea e.6[
handler ?Y%}(3y
* @param everyPage w8G7Jy
* @param currentPage LFl2uV"
* @param totalRecords BQ).`f";d
* @return page :sU!PF[<
*/ d:A\<F
publicstatic Page createPage(int everyPage, int ^g}L`9fL
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currentPage, int totalRecords){ jMTRcj];(
everyPage = getEveryPage(everyPage); 52da]BW<
currentPage = getCurrentPage(currentPage); wj}=@HS,3!
int beginIndex = getBeginIndex(everyPage, )t*S'R
<}<#W/
currentPage); qi(&8in
int totalPage = getTotalPage(everyPage, XAw2 X;F%
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totalRecords); ,m2A
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boolean hasNextPage = hasNextPage(currentPage, hT.4t,wa8
7We?P,A\;
totalPage); f$Gr`d
boolean hasPrePage = hasPrePage(currentPage); yZ?xt'tn
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returnnew Page(hasPrePage, hasNextPage, @P*ylB}?Q
everyPage, totalPage, ~o:rM/!Ba
currentPage, =s`XZkh
,?C|.5
beginIndex); &/ \O2Aw8
} CR%D\I$o
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privatestaticint getEveryPage(int everyPage){ d,zp`S
return everyPage == 0 ? 10 : everyPage; Q1aHIc
} 976E3u"Vt
" ]aQ Hh]f
privatestaticint getCurrentPage(int currentPage){ AEB/8%l};v
return currentPage == 0 ? 1 : currentPage; gmXy>{T
} &B?@@6
fx]\)0n
privatestaticint getBeginIndex(int everyPage, int [Bl
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_`TepX R
currentPage){ Rbx97(wK
return(currentPage - 1) * everyPage; QIR4<]/
} U*
-% M
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privatestaticint getTotalPage(int everyPage, int }9{dR4hD
hfJrQhmE
totalRecords){ H|grbTv,
int totalPage = 0; &mX5&e
Is4%}J!8
if(totalRecords % everyPage == 0) :Tlf4y:/w
totalPage = totalRecords / everyPage; *>EI2HX
else AQE
eIFH
totalPage = totalRecords / everyPage + 1 ; Y'tq m&}
6"BtfQ")
return totalPage; Q&oC]u(="&
} 5oVLv4Z9u
%M|Z}2qv
privatestaticboolean hasPrePage(int currentPage){ L4MxU 2
return currentPage == 1 ? false : true; xnJjCEZ
} aQz|!8Is
mgmWDtxN
privatestaticboolean hasNextPage(int currentPage, Ah6wU|_-g
pWWL{@ J
int totalPage){ %4?SY82
return currentPage == totalPage || totalPage == ZC3tbhV
<m?GJuQ'
0 ? false : true; *LY~l
} L!CX&
uPa/,"p
F?*Dr
} h$E\2lsE
aK8bKlZe
)B-MPuB
^VSt9&
yw;ghP;
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 UN
cYu9[
^n\9AE3
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 AZh@t?)
4^d+l.F
做法如下: BSx j~pun
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 AyQS4A.s[
w8eG;
的信息,和一个结果集List: w$w>N(e
java代码: ovhC42i
Z7tU0
jxRF" GD
/*Created on 2005-6-13*/ 8@Egy%_
package com.adt.bo; /#S4espE
W&fW5af9
import java.util.List; @4 zi]v
ek<PISlci
import org.flyware.util.page.Page; hQgk.$g
FRl3\ZDqrb
/** 'hwV
* @author Joa U%mkhWn
*/ e%P+KX
publicclass Result { 6F|Hg2tpz
DFt=%aV[
private Page page; _hAj2%SL
P!`Q_h6a
private List content; c8bca`
7\7 Brw4
/** yt/20a
* The default constructor 6%\7.h
*/ .ujs`9d_-
public Result(){ \_*?R,$3Y,
super(); S5:"_U
} |i,zY{GI+2
OqfhCNAY
/** n/9 LRZD|w
* The constructor using fields ^ l]]qdNr
* =:xV(GK}
* @param page 'Z*\1Ci
* @param content u)q2YLK8
*/ e3yorQ][
public Result(Page page, List content){ 5PPPd-'Z_
this.page = page; _H~pH7WU
this.content = content; @Og\SZhn
} w0a+8gexi
u+2xrzf
/** kjLsk-
* @return Returns the content. H(5S Kv5
*/ }aHB$}"!
publicList getContent(){ _~X8/p/Qh
return content; B-y0;0
} E%wV
[?|l X$<
/** lKh2LY=j
* @return Returns the page. VTy,43<
*/ _ 6+,R
public Page getPage(){
"?2
return page; aH5t.x79b
} I3}HNGvU
]t.WJC %
/** zh#OD{
* @param content ue6/EN;}
* The content to set. ,$MWk(S
*/ bm|Jb"T0b
public void setContent(List content){ Nt`F0
9S
this.content = content; Z/V`Z* fy
} UA69_E{JCH
LW83Y/7
/** _/QKWk&j
* @param page *([0"
* The page to set. boC>N
*/ h3UZ|B0=
publicvoid setPage(Page page){ Gx(K N57D
this.page = page; p?Z+z
} xWenKY,
} }AMYU>YE=
%8Z|/LGg
|:7EJkKZ
FT*yso:X/
6SW|H"!!
2. 编写业务逻辑接口,并实现它(UserManager, r)9i1rI+
_g^K$+F'}
UserManagerImpl) CI~hmL0
java代码: 5@R15q@c6n
~_dBND?
K]H"qG.K
/*Created on 2005-7-15*/ z. _C*c
package com.adt.service; d+YVyw.z
Q8}TNJsU
import net.sf.hibernate.HibernateException; \jF" nl
vc>^.#7
import org.flyware.util.page.Page; %T&&x2p^=?
uJ|5Ve
import com.adt.bo.Result; IEIxjek
#GDh/t2@
/** |*]X\UE
* @author Joa zCj*:n
*/ =#POMK".6
publicinterface UserManager { ((RpT0rP\
#whO2Mv
public Result listUser(Page page)throws fJF8/IQ4
V\k5h
HibernateException; 7)8rc(58
np'M4^E;
} {jx#^n&5R
;H m-,W
&geOFe}R
5H'b4Cyi`
(04j4teE
java代码: 6S! lD=
m5'__<
2kp|zX(
/*Created on 2005-7-15*/ :uT
fhr
package com.adt.service.impl; T_(e(5
=XRgT1>e
import java.util.List; .^9/ 0.g8t
XDrlJvrPL
import net.sf.hibernate.HibernateException; )'K!)?&d
Y>dg10=
import org.flyware.util.page.Page; BZ\EqB
import org.flyware.util.page.PageUtil; |$.sB|_
N
D:6x*+jah)
import com.adt.bo.Result; r0Y?X\l*
import com.adt.dao.UserDAO; {R1Cxt}
import com.adt.exception.ObjectNotFoundException; v:J.d5
import com.adt.service.UserManager; $E4O^0%/p
;K)?:
/** I).^,%>Z)
* @author Joa L!+[]tB
*/ )K\k6HC.
publicclass UserManagerImpl implements UserManager { 6&OonYsP
uc"[ qT(X
private UserDAO userDAO; My6]k?;}(
J<5vs3[9
/** a`h$lUb-
* @param userDAO The userDAO to set. gKm~cjCB`~
*/ F"@'(b
publicvoid setUserDAO(UserDAO userDAO){ 3$kv%uf{
this.userDAO = userDAO; x9&tlKKxf
} y?R <g^A
fbx;-He!
/* (non-Javadoc) +}G>M=t::
* @see com.adt.service.UserManager#listUser k. ?
T.9
8tFyNl`c
(org.flyware.util.page.Page) d~z<,_r5c
*/ C(%5,|6
public Result listUser(Page page)throws K_lCDiqG
d@>k\6%j
HibernateException, ObjectNotFoundException { bbPd&7
int totalRecords = userDAO.getUserCount(); i_ODgc`H
if(totalRecords == 0) um0}`Xq ^
throw new ObjectNotFoundException 1o6J9kCq^3
R=Ly49
("userNotExist"); n
nnA,
page = PageUtil.createPage(page, totalRecords); *V@MAt
List users = userDAO.getUserByPage(page); g9lg
returnnew Result(page, users); H{tOCYyD
} `bt)'ERO%#
.+JPtL
} kmwrv -W
K7&8;So
GE3U0w6WbK
$qyM
X[
>G3J3P(
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 OTFu4"]M
Ci#5@Q9#w
询,接下来编写UserDAO的代码: S>ylA U;N
3. UserDAO 和 UserDAOImpl: .pu`\BW>
java代码: ~NW5+M(u
t+)GB=C
\tw#pk
/*Created on 2005-7-15*/ j>Bk; f|
package com.adt.dao; OAnn`*5Up
OrH1fhh
import java.util.List; YDzF( ']o:
sp|y/r#
import org.flyware.util.page.Page; ? Ge*~d
~PAbLSL*u
import net.sf.hibernate.HibernateException; T I7Ty+s
/qQ2@k
/** ]#7Y@Yo
* @author Joa 4[EO[x4C
*/ v%8-Al^G
publicinterface UserDAO extends BaseDAO { ;0X|*w1JO
^CZ|ci6bX
publicList getUserByName(String name)throws #y9K-}u
^[\53\R~
HibernateException; Ew,wNR`
*1$~CC7
publicint getUserCount()throws HibernateException; .L TFa.jxA
hpi_0lMkI
publicList getUserByPage(Page page)throws <n~g+ps
!VZCM{
HibernateException; K'rs9v"K|
Nm:<rI,^
} N, +g/o\f
#1!BD!u
^fiRRFr[
md
+`#-D\O
czsoD)N
java代码: C"|_j?
d@`:9
G3
/t 6u"I~
/*Created on 2005-7-15*/ Hr,gV2n
package com.adt.dao.impl; 0}C}\1
ps;o[gB@5
import java.util.List; jxOVH+?l%
nhxd
import org.flyware.util.page.Page; X qva&/-
v5bb|o[{K
import net.sf.hibernate.HibernateException; vc1GmB
import net.sf.hibernate.Query; nz?BLO=
/Ta0}Y(y
import com.adt.dao.UserDAO; 3)MM5
bb$
EsxTBg
/** ~S{\wL53
* @author Joa ZC-evy
*/ WoG
public class UserDAOImpl extends BaseDAOHibernateImpl Oy`\8*Uy__
=xWW+w!r
implements UserDAO { oW1olmpp=
D~?*Xv]s~
/* (non-Javadoc) n[S*gX0
* @see com.adt.dao.UserDAO#getUserByName 7XC}C+
CpdY)SMSL
(java.lang.String) 5<8>G?Y
*/ f2e$BA
publicList getUserByName(String name)throws ]x{ H
_^sSI<&m
HibernateException { ^
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String querySentence = "FROM user in class !Kqj&y5
-ddatc|
com.adt.po.User WHERE user.name=:name"; x=|@AFI
Query query = getSession().createQuery {j4:.fD
w)SxwlW}
(querySentence); soK_l|z:J
query.setParameter("name", name); \D k^\-
return query.list(); =y/Lbe}:
} h pes
|N.q[>^R
/* (non-Javadoc) Bq=](<>>
* @see com.adt.dao.UserDAO#getUserCount() 4~MUc!
*/ NW
Qu-]P
publicint getUserCount()throws HibernateException { x(6.W"-S
int count = 0; A/6nVn
String querySentence = "SELECT count(*) FROM zQ^[=siZ}
6C}Z1lZl
user in class com.adt.po.User"; z#67rh{
Query query = getSession().createQuery nE.s
S5vMP
N
(querySentence); g
{wPw
count = ((Integer)query.iterate().next j`M<M[C*4N
BnY|t2r
()).intValue(); (&x\,19U$
return count; ?bi^h/f
} WZ-{K"56
Ybiz]1d
/* (non-Javadoc) Z+Zh;Ms
* @see com.adt.dao.UserDAO#getUserByPage %cjav
l_IX+4(@b|
(org.flyware.util.page.Page) l),13"?C(
*/ hpKc_|un
publicList getUserByPage(Page page)throws :WTvP$R
SvrV5X
HibernateException { tELnq#<6
String querySentence = "FROM user in class I4ct``Di
<xz-7EqbwX
com.adt.po.User"; P?ol]MwaB
Query query = getSession().createQuery z1A-EeT
!.N=Y;@lY
(querySentence); ~&|i'f[
query.setFirstResult(page.getBeginIndex()) c=E.-
.setMaxResults(page.getEveryPage()); Cagq0-:(p
return query.list(); E&v-(0
} jH/%Z5iu
LM`#S/h
}
0$uS)J\;K
ur5n{0#
+6E<+-N
o?8j*]
.v8=zi:7Y
至此,一个完整的分页程序完成。前台的只需要调用 N=x,96CF
\wd`6
userManager.listUser(page)即可得到一个Page对象和结果集对象 `N,Jiw;bw
~<R~Q:T
的综合体,而传入的参数page对象则可以由前台传入,如果用 ai2}vR
7nIMIkT:
webwork,甚至可以直接在配置文件中指定。 ZS;kCdL
ZXkAw sr
下面给出一个webwork调用示例: 7:<>#
java代码: Ds/zl Z
mJqP#Unik
=~*u(0sJa
/*Created on 2005-6-17*/ -p~B
-,
package com.adt.action.user; K|!)<6ZsG7
P1jkoJ
import java.util.List; c3mlO[(
{$.{VE+v5
import org.apache.commons.logging.Log; v:b%G?o
import org.apache.commons.logging.LogFactory; |9JYg7<
import org.flyware.util.page.Page; I<#kw)W!
4K% YS
import com.adt.bo.Result; "fwuvT
1
import com.adt.service.UserService; Yq.@7cJ
import com.opensymphony.xwork.Action; ,^T2hY`
5Ep
/** 3<lDsb(}0A
* @author Joa c" HCc]
*/ fTcRqov
publicclass ListUser implementsAction{ @UBp;pb}=h
]sE^=;Pv?
privatestaticfinal Log logger = LogFactory.getLog b`=rd 4cpU
9bvd1bKEW
(ListUser.class); Kep?=9r4+
?whp_
private UserService userService; xbIA97g-O,
5$w1[}UUd
private Page page; _E7eJSM.
@n3PCH6:Ao
privateList users; eIl&=gZ6>
Su~`jRN$
/* 3+'w% I
* (non-Javadoc) C<ljBz`,t
* ~a Rq\fx{
* @see com.opensymphony.xwork.Action#execute() Ja2.1v|r.
*/ nwYeOa/t
publicString execute()throwsException{ ,kI1"@Tu
Result result = userService.listUser(page); m-]"I8[
page = result.getPage(); xCD+qP^
users = result.getContent(); Z
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return SUCCESS; 1owoh,V6
} 6ZJQ '9f
&bNj/n/
/** P n DZi
* @return Returns the page. P*Nl3?T
*/ %-.GyG$i
public Page getPage(){ "tIx$?I
return page; ,'}ZcN2)
} _\zfXHp
\/%mabLK
/** CJ >=odK[
* @return Returns the users. hR2.w/2j
*/ K(Nk|gQ
publicList getUsers(){ XafyI*pOX
return users; E&AR=yqk
} w.jATMJ)F
X;0@41t'
/** /:)4tIV
* @param page *@Z'{V\
* The page to set. Z9y:}:j"
*/ ]0O$2 j_ 7
publicvoid setPage(Page page){ ZBWe,Xvq
this.page = page; yO)Qg*r
} el<nY"c
!.A>)+AK
/** g$qh(Z_s
* @param users nK[$ID
* The users to set. - =Hr|AhE
*/ m[XN,IE#u
publicvoid setUsers(List users){ rv[\2@}
this.users = users; wKN9HT
} 1*"Uc!7.%
ueOvBFgZ
/** &+sN=J.x
* @param userService S_atEmQ
* The userService to set. ZL
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*/ 3 ren1
publicvoid setUserService(UserService userService){ U7N<!6
this.userService = userService; H D>{UU?
} utXcfKdt
} i8]r}a
!WmpnPr1
9z?F_=PB!
@9L9c
k dqH36&<
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, @NF8?>!
f{J7a1 `_
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 "(5}=T@,
pfG:PrZ
么只需要: d$ /o\G
java代码: 0WFZx
Ad"
d0,I] "
"v06Fj>q
<?xml version="1.0"?> )]}*oO
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork B sAglem
We`axkC
1.0//EN" "http://www.opensymphony.com/xwork/xwork- *e R$
mMR[(
1.0.dtd"> 9D@Ez"xv
C<pF13*4
<xwork> = 2k+/0ZbP
la-+`
<package name="user" extends="webwork- ;4 &~i
Mo/xEB/O
interceptors"> ]loO 5
er_aol e
<!-- The default interceptor stack name W{`;][
;pNfdII(
--> (-
uk[["3
<default-interceptor-ref .'4*'i:
T F'ssD
name="myDefaultWebStack"/> 5]{YERa'
C'Ymz`iQ
<action name="listUser" `:2C9,Xu
Vo\d&}Q
class="com.adt.action.user.ListUser"> +$9w[ARN+
<param }K/[3X=B
-vMP{,
name="page.everyPage">10</param> 'K`)q6m
<result I|.B-$gH
,Ubnz
name="success">/user/user_list.jsp</result> $?GF]BT
</action> zUh(b=,
a8N!jQc_m
</package> 1ayxE(vMcX
mHP1.Z`
</xwork> :+YFO.7
b`2~
pyN PdEy
?vhW`LXNB
k`?n("j
5rc<ibGh
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 +5Mx0s(5
w9 NUm
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Y3thW@mD05
}>j$Wr_h
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 O&)Y3 O1
33; ytd
Nb$ )YMbA
`1P
&
!vsUL-
我写的一个用于分页的类,用了泛型了,hoho 0ul2rZc
Pvtf_Qo^
java代码: Z/0M9 Q%
>Nov9<p
R(:q^?
package com.intokr.util; )a.U|[:y[+
`a J[
!O
import java.util.List; 2@ad! h
CV` I.
/** { d/k0H
* 用于分页的类<br> q3;HfZ
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ,0~'#x>
* |OC6yN *P)
* @version 0.01 wk3yz6V2
* @author cheng )qKfTtN`
*/ n>@(gDq
public class Paginator<E> { ^v,^.>P
privateint count = 0; // 总记录数 0uZH H
privateint p = 1; // 页编号 Di&tm1R1
privateint num = 20; // 每页的记录数 2sXWeiJy;
privateList<E> results = null; // 结果 )'qZ6%
A5z`3T;1
/** Tx!mW-Lt
* 结果总数 K
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*/ p1Els/|
publicint getCount(){ WUHijHo5(8
return count; NZ
Xmrc{S
} :+u?A
b&!X#3(KT
publicvoid setCount(int count){ $idYG<],
this.count = count; @ )1u
} Kj'uTEM
s Ce{V*ua
/** HK }C<gg
* 本结果所在的页码,从1开始 M[X& Q
* 8&3G|m1-2
* @return Returns the pageNo. i |C'_gw`n
*/ @P%&Dha
publicint getP(){ wL}=$DN
return p; TEY%OIzU+
} M*t{?o/t;
RhYf+?2
/** nlJxF5/
* if(p<=0) p=1 s:Memvf
* zX)uC<
* @param p L"AZ,|wIk
*/ $oh}!Smt
publicvoid setP(int p){ {|
Tl3
if(p <= 0) D].1X0^hp
p = 1; w,^!kO0)~8
this.p = p; Ix}:!L
} Jz3u r)|
Og^b'Kx/
/** `,xKK+~YG-
* 每页记录数量 OJ&~uV >2
*/ ]mYY1%H8M
publicint getNum(){ 'H97D-86/
return num; n&&X{Rl
} o@"H3
gz
G!wFG-Y}
/** O{Wy;7i
* if(num<1) num=1 kvKbl;<
*/ z`'{l{
publicvoid setNum(int num){ @'dtlY5;
if(num < 1) YX-G>.Pc
num = 1; *;Sj&O
this.num = num; b1_HDC(
} IRD?.K]*
|LWG7
ZE
/** ]M#_o]
* 获得总页数 iFpJ/L
*/ .]P@{T||Y
publicint getPageNum(){ }ufH![|[r
return(count - 1) / num + 1; >=$( ,8"
}
85m_jmh[
tK0?9M.)
/** V
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* 获得本页的开始编号,为 (p-1)*num+1 [$f
*/ Bh<)e5lP:
publicint getStart(){ fsb_*sh&
return(p - 1) * num + 1; Q/L:0ovR
} :IvKxOv
qauk,t
/** 66!cfpM
* @return Returns the results. |h4aJv
*/ >}Fe9Y.o
publicList<E> getResults(){ 6f(K'v
return results; xV}-[W5sr'
} 6o!+E@V
b
?o?~Df&
public void setResults(List<E> results){ "1yXOy^2
this.results = results; Fn1|Wt*
} J1KV?aR
rISg`-
public String toString(){ p78X,44xg
StringBuilder buff = new StringBuilder *+rO3% ;t
;(5b5PA
(); iW9G0Ay
buff.append("{"); '+JU(x{CCl
buff.append("count:").append(count); M |6l
buff.append(",p:").append(p); B^Fe.t y
buff.append(",nump:").append(num); 09HlL=0q
buff.append(",results:").append ?%(:
j&(aoGl@
(results); $GB/}$fd&
buff.append("}"); AT+7!UGL
return buff.toString(); R,>LUa*u
} 2Sz?r d,0f
BUvE~l.,|
} $t}t'uJ
jv_z%`
Rf9;jwU