Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 TdhfX {nk
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 y>o:5':;'
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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 ,d"T2Hy
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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 jqUVERbc
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分页支持类: l6M?[
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java代码: ,Py\Cp=Dw
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package com.javaeye.common.util; K#3^GB3P
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import java.util.List; L+t
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publicclass PaginationSupport { }$ y.qqG
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publicfinalstaticint PAGESIZE = 30; ,@*5x'auK
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privateint pageSize = PAGESIZE; $LP(\T([
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privateList items; Z{8%Cln
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privateint totalCount; p=+Y7NE)
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privateint[] indexes = newint[0]; 5'!fi]Z
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privateint startIndex = 0; .k#PrT1C
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public PaginationSupport(List items, int dXyMRGRUq
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totalCount){ kZ9Gl!g
setPageSize(PAGESIZE); r=j?0k '}]
setTotalCount(totalCount); 5ibr1zs
setItems(items); Yy~x`P'g!
setStartIndex(0); e$LC
} 9Po>laT
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public PaginationSupport(List items, int +3,7 Apj
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totalCount, int startIndex){ Agd"m4!
setPageSize(PAGESIZE); <bcf"0A
setTotalCount(totalCount); 0\mf1{$"!7
setItems(items); _Sjj|j
setStartIndex(startIndex); vfSPgUB)
} ,='Ihi
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public PaginationSupport(List items, int _L,~WYRo
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totalCount, int pageSize, int startIndex){ &A:&2sP8
setPageSize(pageSize); Dj/Hz\
setTotalCount(totalCount); Df"PNUwA"
setItems(items); w1Bkz\95
setStartIndex(startIndex); rCJ$Pl9R
} .ATpwFal
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publicList getItems(){ ]&D dy&V
return items; C eEhe
} 7mtx^
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publicvoid setItems(List items){ 9Og
this.items = items; :7{GOx
} [I;C6p
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publicint getPageSize(){ 2j
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return pageSize; ;CO qu#(
} l!1_~!{y
1 |z4]R,<
publicvoid setPageSize(int pageSize){ jHEP1rNHE
this.pageSize = pageSize; `8ob Xb
} lhM5a
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publicint getTotalCount(){ A6z2KVk
return totalCount; S{llpp{E
} 1
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publicvoid setTotalCount(int totalCount){ 7\@c1e*e
if(totalCount > 0){ IlJ"t`Z9)
this.totalCount = totalCount; :1d;jx>
int count = totalCount / <gPM/4$G
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pageSize; ~,,r\Y+
if(totalCount % pageSize > 0) L IKuK#
count++; -axKnfj
indexes = newint[count]; \: ZDY(>1
for(int i = 0; i < count; i++){ a3n
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indexes = pageSize * E"}%$=yK
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i; Q7amp:JFb
} i59}6u_f
}else{ -|x7<$Hw
this.totalCount = 0; -.Wwo(4
} drpx"d[c
} =LGM[Z3$s
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publicint[] getIndexes(){ ,wf_o%'eW
return indexes; x,: k/]
} Ztk%uc8_lM
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publicvoid setIndexes(int[] indexes){ L1_O!EQ
this.indexes = indexes; aj|3(2;Kp
} ll}_EUF|
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publicint getStartIndex(){ <\nM5-wR
return startIndex; ^5Y<evjm
} 7(5d$ W
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publicvoid setStartIndex(int startIndex){ E2l"e?AN~
if(totalCount <= 0) h~QQ-
this.startIndex = 0; -8)C6"V{
elseif(startIndex >= totalCount) aP (~l_
this.startIndex = indexes aGWO3Nk
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[indexes.length - 1]; !UT!PX)
elseif(startIndex < 0) 2V8"jc
this.startIndex = 0; e O~p"d-|
else{ Ju5Dd\
this.startIndex = indexes `D3q!e
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[startIndex / pageSize]; ;\"5)S
} 5%wA"_
} q'fOlq
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publicint getNextIndex(){ iTevl>p!
int nextIndex = getStartIndex() + ipG 0ie+
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pageSize; J3+qnT8X
if(nextIndex >= totalCount) ,1~B7Zd
return getStartIndex(); ((?"2 }1r
else TlO=dLR7d
return nextIndex; Obu 6k[BE.
} =2*2$
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publicint getPreviousIndex(){ P:J|![
int previousIndex = getStartIndex() - } A6z%|d
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pageSize; 3]iw3M
if(previousIndex < 0) ZT"vVX-)G
return0; o^5UHFxTCB
else uih8ZmRt
return previousIndex; lhQMR(w^
} Nnn~7
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} bs}SFT L
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抽象业务类 MF$Dx| Tcj
java代码: 'oGMr=gp<&
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/** s o: o
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* Created on 2005-7-12 O*2{V]Y
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*/ +-x+c:
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package com.javaeye.common.business; Lcg1X3$G
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import java.io.Serializable; F" G+/c/L
import java.util.List; BGNZE{K4"
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import org.hibernate.Criteria; o8g]ho
import org.hibernate.HibernateException; H
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import org.hibernate.Session; "1dpv\
import org.hibernate.criterion.DetachedCriteria; )#Ecm<.^
import org.hibernate.criterion.Projections; !#1UTa
import lib^JJF
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org.springframework.orm.hibernate3.HibernateCallback; mE+=H]`.p
import PMiu "
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org.springframework.orm.hibernate3.support.HibernateDaoS H>\lE2
1)e[F#|
upport; '[[IalQ?
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import com.javaeye.common.util.PaginationSupport; zzC{I@b
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public abstract class AbstractManager extends nbw8YO(=
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HibernateDaoSupport { 2#R0Bd
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privateboolean cacheQueries = false; 5a5JOl$8
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privateString queryCacheRegion; YYe<StyH
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publicvoid setCacheQueries(boolean !~m PxGY
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cacheQueries){ \*fXPJ4
this.cacheQueries = cacheQueries; OK@yMGz1I
} %Zeb#//Jz
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publicvoid setQueryCacheRegion(String V+u0J"/8
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queryCacheRegion){ g|]Hm*
this.queryCacheRegion = pB VzmQF
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queryCacheRegion; `)i4ZmE|
} Pr/q?qZY
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publicvoid save(finalObject entity){ !(_qM
getHibernateTemplate().save(entity); r-hb]!t
} +nYF9z2
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publicvoid persist(finalObject entity){ 5uM`4xkj
getHibernateTemplate().save(entity); uE#"wm'J
} 0LWV.OIIC
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publicvoid update(finalObject entity){ \O>;,(>i
getHibernateTemplate().update(entity); `j6O
} k
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publicvoid delete(finalObject entity){ M\08 7k
getHibernateTemplate().delete(entity); SR4 mbQ:
} &61h*s
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publicObject load(finalClass entity, rB =c
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finalSerializable id){ EP{ji"/7[
return getHibernateTemplate().load AB.ZmR9|
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(entity, id); {ZUgyGE{
} 7%|HtBXv^
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publicObject get(finalClass entity, $3Sm?
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finalSerializable id){ ~. 5[
return getHibernateTemplate().get n}J!?zZc
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(entity, id); ad<ZdO*h
} Xq$9H@.
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publicList findAll(finalClass entity){ q] '2'"k
return getHibernateTemplate().find("from !imjfkG
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" + entity.getName()); AHplvksb
} e1H2w?
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publicList findByNamedQuery(finalString 8$ _8Yva"e
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namedQuery){ 0[-@<w ^j
return getHibernateTemplate `9DW}
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().findByNamedQuery(namedQuery); DPWnvd
} )5<c8lzp
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publicList findByNamedQuery(finalString query, xf3/J{n3
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finalObject parameter){ gGbJk&E
return getHibernateTemplate 9!Bz)dJ3
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().findByNamedQuery(query, parameter); JF9r[%
} Tu=~iQ
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publicList findByNamedQuery(finalString query, 2()/l9.O'
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finalObject[] parameters){ ]2mfby
return getHibernateTemplate dJ7 !je1N*
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().findByNamedQuery(query, parameters); .#Lu/w' -M
} ?fvK<0S`
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publicList find(finalString query){ @=6$ImU
return getHibernateTemplate().find "IzM:
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(query);
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} %xN91j["
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publicList find(finalString query, finalObject b59NMGn
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parameter){ A~wVY
return getHibernateTemplate().find pLpWc~#
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(query, parameter); 3W@ta1
} ;TCT%j`^o
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public PaginationSupport findPageByCriteria .10$n*
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(final DetachedCriteria detachedCriteria){ $+w -r#,
return findPageByCriteria ds'7zxy/
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 0t0m?rVW
} l\t<_p/I)^
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public PaginationSupport findPageByCriteria a>)|SfsE
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(final DetachedCriteria detachedCriteria, finalint j<-YK4.t
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startIndex){ ^r^) &]
return findPageByCriteria O`'r:W
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(detachedCriteria, PaginationSupport.PAGESIZE, 5H/D~hr&
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startIndex); f26hB;n
} JrwR:_+|
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public PaginationSupport findPageByCriteria E3 aj
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(final DetachedCriteria detachedCriteria, finalint oz?pE[[tm
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pageSize, oGqbk x
finalint startIndex){ j#
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return(PaginationSupport) oTxE]a,
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getHibernateTemplate().execute(new HibernateCallback(){ S,^)\=v
publicObject doInHibernate r(
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(Session session)throws HibernateException { "']|o ~B
Criteria criteria = c>yqq'
//-;uEO
detachedCriteria.getExecutableCriteria(session); U<.,"`=l
int totalCount = +jGSD@32>
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((Integer) criteria.setProjection(Projections.rowCount W3 2]#M=
>Ef{e6
()).uniqueResult()).intValue(); .a]9 rQQ&_
criteria.setProjection ~Jx0#+z9V
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(null); (@;=[5+
List items = gSXidh}^
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criteria.setFirstResult(startIndex).setMaxResults ^U]B&+m
;wj8:9
;
(pageSize).list(); QX|y};7\e
PaginationSupport ps = :6y;U
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new PaginationSupport(items, totalCount, pageSize, I?Ct@yxhF'
"/qm,$
startIndex); I2<5#|CXpZ
return ps; >sm<$'vZ/
} -)$5[jM]
}, true); )~H&YINhn
} #Bi8>S
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public List findAllByCriteria(final ad,pHJ`
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DetachedCriteria detachedCriteria){ 5 p! rZ
return(List) getHibernateTemplate \ 3HB
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().execute(new HibernateCallback(){ QK@[b3-h1
publicObject doInHibernate T6fm`uL&L
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(Session session)throws HibernateException { ]U)Yg
Criteria criteria = 9a3mN(<
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detachedCriteria.getExecutableCriteria(session); \9T/%[r#
return criteria.list(); ud:5_*
} ?'+kZ|
}, true); .Arcsg
} xdkC>o4>
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public int getCountByCriteria(final K *xca(6
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DetachedCriteria detachedCriteria){ \9`76*X6
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Integer count = (Integer) V"DilV$v
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getHibernateTemplate().execute(new HibernateCallback(){ Va3/#is'
publicObject doInHibernate 8a,pDE
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(Session session)throws HibernateException { x4%1P w
Criteria criteria = [ T!0ka
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detachedCriteria.getExecutableCriteria(session); $hq'9}ASOL
return SVJt= M
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criteria.setProjection(Projections.rowCount $Z[W}7{pt#
)H|cri~D
()).uniqueResult(); c-q=Ct
} 8D6rShx =
}, true); G"D=ozr
return count.intValue(); WI}cXXUKm0
} caXSt2|'
} =@y
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用户在web层构造查询条件detachedCriteria,和可选的 =Cg1I\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ['jr+gIfQ
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PaginationSupport的实例ps。 ZYo?b"6A
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ps.getItems()得到已分页好的结果集 R8C#DB
ps.getIndexes()得到分页索引的数组 E)z=85;_p
ps.getTotalCount()得到总结果数 TAp8x
ps.getStartIndex()当前分页索引 ]mT2a8`c.r
ps.getNextIndex()下一页索引 \_l4li
ps.getPreviousIndex()上一页索引 Ze"m;T
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 g#b9xTGJ^
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Df5!z \dx
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一下代码重构了。 #$ooV1E
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我把原本我的做法也提供出来供大家讨论吧: rBUWzpE"
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首先,为了实现分页查询,我封装了一个Page类: i)th] 1K%
java代码: E_-QGE/1
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/*Created on 2005-4-14*/ ;DXg
package org.flyware.util.page; e6gLYhf&
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/** hI 1or4V
* @author Joa \dJOZ2J<z
* TX).*%f[r
*/ N~~
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publicclass Page { 9Yd"Y-
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/** imply if the page has previous page */ :JIJ!Xn)
privateboolean hasPrePage; 0)rayzv
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/** imply if the page has next page */ 2;ju/9x
privateboolean hasNextPage; "/nbcQ*s*E
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/** the number of every page */ #7['M;_
privateint everyPage; `!Yd$=*c_&
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/** the total page number */ %U6A"?To
privateint totalPage; DIw9ov>k
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/** the number of current page */ 53WCF[
privateint currentPage; __Zex5Y#-
mx5#K\
/** the begin index of the records by the current qPBOt;N
)kD B*(?
query */ nrg$V>pD
privateint beginIndex; nzU;Bi^m
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/** The default constructor */ mgMa)yc!dp
public Page(){ otX/sg.B*
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} 3JEg3|M(
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/** construct the page by everyPage `BVXF#sb
* @param everyPage K[yP{01
* */ 0.)q5B`
public Page(int everyPage){ foUB/&Ee
this.everyPage = everyPage; 0<93i
} -9Dr;2\
:!Nx'F9a
/** The whole constructor */ #>6Jsnv1
public Page(boolean hasPrePage, boolean hasNextPage, u|LDN*#DW
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% {-r'Yi%
int everyPage, int totalPage, 2"HG6"Rr
int currentPage, int beginIndex){ 5W0s9yD
this.hasPrePage = hasPrePage; 0n}v"61q
this.hasNextPage = hasNextPage; (67byO{
this.everyPage = everyPage; f,x;t-o+R
this.totalPage = totalPage; q%LjOPE
V
this.currentPage = currentPage; [*M':
this.beginIndex = beginIndex; -^3uQa<zN^
} -lrcb/)Gz
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/**
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* @return Z~F*$jn
* Returns the beginIndex. )-0+O=v
*/ /_qHF-
publicint getBeginIndex(){ #Vu;R5GZ}
return beginIndex; 1'N<ITb
} C]Y%dQh+a
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/** @lWYc`>}
* @param beginIndex D|*yeS4>
* The beginIndex to set. K|Eelhm
*/ $01csj
publicvoid setBeginIndex(int beginIndex){ &u~Pp=kv
this.beginIndex = beginIndex; y)"rh /;
} #0PZa$kM(o
n
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/** CF
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* @return zU0SlRFu
* Returns the currentPage. H32o7]lT
*/ 9c%CCZ
publicint getCurrentPage(){ \t5_V)P
return currentPage; XOLE=zdSp
} KY}H-
ltlo$`PR
/** hw.>HT|.N
* @param currentPage bYoBJ
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* The currentPage to set. 8
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*/ w51l;2$des
publicvoid setCurrentPage(int currentPage){ U>OAtiq JX
this.currentPage = currentPage; D(OJr5Gg
} 1$+8wDVwad
@+l=R|
/** J?EDz,
* @return 8t. QFze?
* Returns the everyPage. I&m' a
*/ o2'Wu:Y"
publicint getEveryPage(){ 8N+T=c
return everyPage; .cHkh^EDY
} %`QgG
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/** 8d2\H*a9~
* @param everyPage `a!9_%|8
* The everyPage to set. C
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*/ KyyVO"
publicvoid setEveryPage(int everyPage){ z:$ibk4#h
this.everyPage = everyPage; )P>/g*
} }Z{FPW.QK
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/** YCQ$X
* @return uT'l.*W6i
* Returns the hasNextPage. >:4`y"0
*/ jCXBp>9$M
publicboolean getHasNextPage(){ &q@brX<,=
return hasNextPage; .6T0d
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} %<x!mE x
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/** P%H Dz
* @param hasNextPage Fe4>G8uuwn
* The hasNextPage to set. 1.+6x4%rV
*/ =JW-EQ6[T
publicvoid setHasNextPage(boolean hasNextPage){ e0h[(3bXs$
this.hasNextPage = hasNextPage; +'-.c"
} vg5_@7
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/** EEnl'
* @return M2N8?Ycv3
* Returns the hasPrePage. HFI0\*xn(
*/ g&85L$
publicboolean getHasPrePage(){ KN[;z2i
return hasPrePage; S<-nlBs.
} 0#Lmajs
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/** W7
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* @param hasPrePage k}Q<#
* The hasPrePage to set. I8j:{*h
*/ kaXq.
publicvoid setHasPrePage(boolean hasPrePage){ pmvd%X\f
this.hasPrePage = hasPrePage; ];4!0\M
} U: Wet,
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/** gK9d `5
* @return Returns the totalPage. !{(Bc8
hT
* *<!q@r<d
*/ &H]/'i-
publicint getTotalPage(){ RG""/x;
return totalPage; *;]}`r
} }ePl&-9T
y/c3x*l.xL
/** <JH,B91
* @param totalPage ?KOw~-u
* The totalPage to set. jT=|!,Pn
*/ <y] 67:"<v
publicvoid setTotalPage(int totalPage){ QcW8A ,\q
this.totalPage = totalPage; 8"9&x}
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} uT4|43<
G
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} M@{#yEP
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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 +IWH7 qRtp
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个PageUtil,负责对Page对象进行构造: ~cCMLK em
java代码: @)uV Fw"\
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/*Created on 2005-4-14*/ UGI<V!
package org.flyware.util.page; w CB*v<*
v={{$=/t
import org.apache.commons.logging.Log; KDq="=q
import org.apache.commons.logging.LogFactory; o~IAZU39
~qrSHn}+PU
/**
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* @author Joa p8_^6wfg
* tLTavE[@
*/ O*~z@"\
publicclass PageUtil {
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privatestaticfinal Log logger = LogFactory.getLog $M 8&&M
>ep<W<b
(PageUtil.class); 0bDc
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/** d"9tP&
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* Use the origin page to create a new page >8"Svt$
* @param page M% \T5
* @param totalRecords ]=qauf>3
* @return oCaYmi=:
*/ &sWr)>vs
publicstatic Page createPage(Page page, int p8~lGuH
!%,7*F(
totalRecords){ jU j\<aW
return createPage(page.getEveryPage(), P3&s<mh
*9EwZwE_K
page.getCurrentPage(), totalRecords); Yt]`>C[|D
} 2!J#XzR0W
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/** 7 H
* the basic page utils not including exception y9 {7+]
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handler |l;
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* @param everyPage WzN c=@[W
* @param currentPage #T_!-;(Z
* @param totalRecords #ODP+>-IjB
* @return page \5r^D|Rp}
*/ vn^O m-\
publicstatic Page createPage(int everyPage, int vPNbV
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currentPage, int totalRecords){ l#KcmOz
everyPage = getEveryPage(everyPage); mrP48#Y+l
currentPage = getCurrentPage(currentPage); S{+t>en
int beginIndex = getBeginIndex(everyPage, x|0C0a\"A
2`$*HPj+G
currentPage); gT+g@\u[
int totalPage = getTotalPage(everyPage, a|7C6#iz$
/:4J
totalRecords); @.eN+o9|
boolean hasNextPage = hasNextPage(currentPage, XIl<rN@-
Jw;~ $
totalPage); @*YF!LdU{M
boolean hasPrePage = hasPrePage(currentPage); 5E'/8xp bB
rv*{[K
returnnew Page(hasPrePage, hasNextPage, L3, /7
everyPage, totalPage, 6VGY4j}:(
currentPage, :2?g_
"`49m7q1H
beginIndex); kw#X,hP
} (u@:PiU/eP
aj&L
Z DD6
privatestaticint getEveryPage(int everyPage){ oRWje#4O
return everyPage == 0 ? 10 : everyPage; =OHX5:Z
} 5~[7|Y
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privatestaticint getCurrentPage(int currentPage){ I@cw=_EQL
return currentPage == 0 ? 1 : currentPage; S;% &X
} ,<Q
pWV_KS
privatestaticint getBeginIndex(int everyPage, int d?*]/ZiR
=
j1Jl^[
currentPage){ >a?Bk4w
return(currentPage - 1) * everyPage; v1OVrk>s>
} fvC,P#z'|
Ss>pNH@c
privatestaticint getTotalPage(int everyPage, int |U|>YA1[b
J\@6YU[A
totalRecords){ R.^]{ 5
int totalPage = 0; ^^N|:80
Jl~ *@0(
if(totalRecords % everyPage == 0) ( eTrqI`
totalPage = totalRecords / everyPage; 'Lrn<
else 6m:$mhA5
totalPage = totalRecords / everyPage + 1 ; GmH DG-
7?Wte&C];p
return totalPage; ..)J6L5l
} $l]:2!R
qIi
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privatestaticboolean hasPrePage(int currentPage){ _i05'_
return currentPage == 1 ? false : true; [:y:_ECs6
} T8o](:B~
m)Plv+R}
privatestaticboolean hasNextPage(int currentPage, fqgp{(`@>
6gV*G
int totalPage){ #r'MfTr
return currentPage == totalPage || totalPage == &b} \).5E
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0 ? false : true; ~[ufL25K
} B0@
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e|]e\Or>
XGl2rX&
} nI*.(+h
<fUo@]Lv
S^rf^%
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h=#w< @
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。 `B)@
_,J+b R+b
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 hq=;ZI
|7|S>h^
做法如下: Hl$W+e|tj
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 NrqJf-ldo
<s9{o
uZ
的信息,和一个结果集List: b>uD-CSA
java代码: (;{X-c}?
_SBbd9
Z 1HH0{q-A
/*Created on 2005-6-13*/ y :;.r:
package com.adt.bo; 9;@p2t*v
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import java.util.List; ^&>B,;Wu
7ch9Pf
import org.flyware.util.page.Page; mLhM_=
47q>
q
/** p'R<yB)V
* @author Joa o2!738
*/ Nfa&r
publicclass Result { S{=5nR9 j
/WN YS
private Page page; `_\KN_-%Vu
I C
private List content; [HILK`@@
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/** | b'Ut)E
* The default constructor E%mEfj7
*/ nfEbu4|
public Result(){ W==~9
super(); 2R/|/>T v
} 9!( 8o
T\l`Y-vu
/** *tXyd<_Hd
* The constructor using fields &6sF wK
* *9'3 `^l
* @param page @:>"VP<(
* @param content Z
[!"x&H]h
*/ -#Z df|
public Result(Page page, List content){ ^DYS~I%s
this.page = page; 5$9$R(KU
this.content = content; *&_*G~>D
} 0 +=sBk (
NqD]p{>Y
/** tV)CDA&Z
* @return Returns the content. zgb$@JC
*/ '_c/CNs
publicList getContent(){ 'z$N{p40m
return content; 7+HK_wNi
} $TIeeTB
:j&enP5R(q
/** ~o'1PAW7
* @return Returns the page. xUdF.c
*/ YSD G!
public Page getPage(){ y7HFmGM
return page; x%mRDm~-
} ~gI%lORqN
dFz"wvu` o
/** 9?l a5
* @param content dtTn]}J
* The content to set. 3TwjC:Yhv2
*/ VF?H0}YSHb
public void setContent(List content){ '/>Mr!H#
this.content = content; Wiis<^)
} DDrR9}k
hP6f
/** B;9,Qbb
* @param page !l[;,l
* The page to set. F[ E'R.:
*/ '@{:FrG*U
publicvoid setPage(Page page){ o 4F'z
this.page = page; MPB[~#:
} 7b"fpB
} |
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u^2`$W
alb3oipOB
Y%
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2. 编写业务逻辑接口,并实现它(UserManager, @O#!W]6NT6
Cut~k"lv
UserManagerImpl) >_}isCd,
java代码: @|Pm%K`1
_(m72o0g>>
D \ rns+
/*Created on 2005-7-15*/ |1@O>GG
package com.adt.service; j,YrM?Xdo
tT]@yo|?e/
import net.sf.hibernate.HibernateException; 6"-$WUlg
nb_/1{F
import org.flyware.util.page.Page; $ f:uBhM
o5Oig
import com.adt.bo.Result; -E7mt`:d
Z
'5itN^
/** YSnh2 Bq
* @author Joa J9T2 p\5
*/ 7@c!4hmrU
publicinterface UserManager { Myc-lCE
$LXa]
public Result listUser(Page page)throws XCM!8x?K
Jm4uj&}3
HibernateException; Y'/6T]a
\[G'cE
} ifn=De3+
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O nXo0PV/(
{it.F4.
Ct=bZW"j/
java代码: IyO0~Vx>
O=Su
E/q
kQ+y9@=/g
/*Created on 2005-7-15*/ PZ]tl
package com.adt.service.impl; 5_9`v@-4_
w{tA{ {
import java.util.List; A{_CU-,
v47' dC
import net.sf.hibernate.HibernateException; J jAxNviG
WuK<?1meN
import org.flyware.util.page.Page; V!:!c]8F
import org.flyware.util.page.PageUtil; e:G~P
u`
>.wZEQ6QK
import com.adt.bo.Result; eT%x(P
import com.adt.dao.UserDAO; D,IT>^[^7
import com.adt.exception.ObjectNotFoundException; HlE8AbEg
import com.adt.service.UserManager; J&6p/'UPZ
p3P8@M
/** P& 1$SWNyW
* @author Joa w:zo
\
*/ <K)]kf
publicclass UserManagerImpl implements UserManager { zjoo;(?D|
J6#h~fp v
private UserDAO userDAO; 6mcb'hy
QSaDa@OV
/** JC'3x9_<z
* @param userDAO The userDAO to set. SQ)BS/8A
*/ ;lmg0dtJ
publicvoid setUserDAO(UserDAO userDAO){ m=}h7&5 p
this.userDAO = userDAO; hj];a,Br&
} aImzK/
)"TVR{I%B
/* (non-Javadoc) {C w.?JU
* @see com.adt.service.UserManager#listUser %M
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Jt$YSp=!!
(org.flyware.util.page.Page) &g?GF\Y
*/ g1t6XVS$9
public Result listUser(Page page)throws QFnuu-82"
ld(60?z>FH
HibernateException, ObjectNotFoundException { i9 aR#
int totalRecords = userDAO.getUserCount(); I[E 6N2
if(totalRecords == 0) b`e_}^,c
throw new ObjectNotFoundException Ug*B[q/
~&~4{
("userNotExist"); c|<F8n
page = PageUtil.createPage(page, totalRecords); hNc8uV{r=
List users = userDAO.getUserByPage(page); CVO_F=;
returnnew Result(page, users); nf
pO
} ,!>
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} Yo %U{/e
t'K+)OK
th{J;a
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 + }"+
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询,接下来编写UserDAO的代码: V_3oAu54s{
3. UserDAO 和 UserDAOImpl: [FhYQI
java代码: +c8`N'~
|k~AGc
[>NMuwtG
/*Created on 2005-7-15*/ -UEi
package com.adt.dao; _sy{rnaqvb
4`?PtRX
import java.util.List; 5 =;cN9M@
|ts0j/A]Pi
import org.flyware.util.page.Page; ]{=y8]7
bB4FjC':
import net.sf.hibernate.HibernateException; 2>jk@~Z1:u
+xuv+mo
/** X&[Zk5DU*
* @author Joa KaEaJ
*/ kO)Y|zQ
publicinterface UserDAO extends BaseDAO { !WXV1S
,OlS>>,
publicList getUserByName(String name)throws |2'WSAWG
">T\]V$R
HibernateException; -+ F,L8
&/m^}x/_W
publicint getUserCount()throws HibernateException; k*_Gg
'n h^;
publicList getUserByPage(Page page)throws `NhG|g
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HibernateException; v
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'7oR|I
} &Sb)a
zgFL/a<
oY ~q^Y
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((Av3{05H&
java代码: ta95]|z"j
8i$|j~M a
l!gX-U%-
/*Created on 2005-7-15*/ (P E.v1T
package com.adt.dao.impl; a;5clonB
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q3
import java.util.List; <<
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hXFT(J=
import org.flyware.util.page.Page; xjBY6Ylz
KsGW@Ho:
import net.sf.hibernate.HibernateException; 9'(^Coq
import net.sf.hibernate.Query; UD14q~ (1Z
io\t>_
import com.adt.dao.UserDAO; EkV#i
:Xy51p`.;]
/** NcbW"Qv3
* @author Joa Z>UM gu3c
*/ ;8=Bee4
public class UserDAOImpl extends BaseDAOHibernateImpl <LZ#A@]71
"~ =O`5V
implements UserDAO { S?Cd,WxT
m>Z3p7!N}
/* (non-Javadoc) O-.G("
* @see com.adt.dao.UserDAO#getUserByName KHP/Y{mH
!L+b{
(java.lang.String) ~_0XG0oA
*/ 2iKteJ@h)
publicList getUserByName(String name)throws E6R\DM
kJ%a;p`O
HibernateException { 4,@jSr|I3i
String querySentence = "FROM user in class pj7al;
xjD$i'V+
com.adt.po.User WHERE user.name=:name"; K:e[#b8:R
Query query = getSession().createQuery S*n5d >;
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(querySentence); Tcv/EST
query.setParameter("name", name); {li
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return query.list(); AaU!a
} 'uzHI@i
9e.v[K~
/* (non-Javadoc) 43g1/,klm
* @see com.adt.dao.UserDAO#getUserCount() zA?AX1%Wa
*/ 3u t<o-
publicint getUserCount()throws HibernateException { ^fN/
int count = 0; ?*UWg[
String querySentence = "SELECT count(*) FROM R`o
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kbvF
9#
user in class com.adt.po.User"; -+i7T^@|
Query query = getSession().createQuery -p0*R<t
c0l?+:0M
(querySentence); 16N|
count = ((Integer)query.iterate().next 7}NvO"u
f/z]kfgw
()).intValue(); >mtwXmI
return count; Zqf
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} F <iV;+
9s!R_R&W.
/* (non-Javadoc) ;dfIzi
* @see com.adt.dao.UserDAO#getUserByPage \PZ;y=]p}
]N\D^`iQ
(org.flyware.util.page.Page) K}N~KDW R|
*/ d" 0&=/
publicList getUserByPage(Page page)throws Ya~Th)'>q
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HibernateException { ^N^s|c'
String querySentence = "FROM user in class s(Wys^[g
-|u
yJh
com.adt.po.User"; nm_taER
Query query = getSession().createQuery /?j
kVy*"
N2|NYDQs
(querySentence); yXIJeo"
query.setFirstResult(page.getBeginIndex()) j"Ew)6j
.setMaxResults(page.getEveryPage()); 00SS<iX
return query.list(); @K S .H
} [j
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} KbciRRf!k
~Hd* Xl
g/FT6+&T.
Kc@Sw{JR#7
zRgGSxn
至此,一个完整的分页程序完成。前台的只需要调用 ZmkH55Cn
!]fSS)\H
userManager.listUser(page)即可得到一个Page对象和结果集对象 1Ke9H!_P
dEI!r1~n
的综合体,而传入的参数page对象则可以由前台传入,如果用 yK"HHdYTV
=eS?`|
webwork,甚至可以直接在配置文件中指定。 0dsL%G~/N
RH7!3ye
下面给出一个webwork调用示例: zFDtC-GF
java代码: pVzr]WFx
+~:OUR*>
b&Laxki
/*Created on 2005-6-17*/ 2dB]Lw@s
package com.adt.action.user; K:VZ#U(_
B>S>t5$
import java.util.List; CQmozh-
^U*1_|Jh
import org.apache.commons.logging.Log; (7&b)"y
import org.apache.commons.logging.LogFactory;
JJs*2y
import org.flyware.util.page.Page; egr"og{
?|_i"*]l
import com.adt.bo.Result; oLq N
import com.adt.service.UserService; '6g-]rE[
import com.opensymphony.xwork.Action; M$!-B,1BX
{KK/mAp{
/** Yi[MoYe/K
* @author Joa rf`xY4I\
*/ RFSwX*!
publicclass ListUser implementsAction{ o!&+ _BKw
Brd9"M|d
privatestaticfinal Log logger = LogFactory.getLog / $s(OFbi#
M^e}w!U
(ListUser.class); 5yj# 9H
bVa?yWb.
private UserService userService; Q`;eI
a6U
OZz!8-|wE
private Page page; i6P$>8jBQ-
k=d0%}
`M(
privateList users; ^ rUq{
J,=ZUh@M
/* 1U^KN~!
* (non-Javadoc) eJ ^I+?h
* Ejf5M\o
* @see com.opensymphony.xwork.Action#execute() LylCr{s7
*/ Xx2t0AIB
publicString execute()throwsException{ D6fd(=t1Z
Result result = userService.listUser(page); 'qG-)2
t
page = result.getPage(); ox\D04:M
users = result.getContent(); R>&8%%#
return SUCCESS; \P"Ol\@
} y!rJ}e
darbL_1
/** 5}! 36SO\
* @return Returns the page. r1}1lJ>7H
*/ \MdieO*
public Page getPage(){ Eht8~"fj
return page; ][#|5UK8L
} .RAyi>\e
CvEIcm=t
/** lOe|]pQ.,
* @return Returns the users. t.
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*/ =8rNOi
publicList getUsers(){ {9Ok^O
return users; JBZ1DZAWC
} f/\S:x-B
7[K3kUm[
/** :>_oOn[ _
* @param page *DZ7,$LQ~D
* The page to set. \}Iq-Je
*/ Y7I\<JG<
publicvoid setPage(Page page){ 0V^I.S/q
this.page = page; F0r2=f(?
} agkKm?xIL
7|_2@4-W6
/** 3-1a+7fD
* @param users .j>MsQP#\C
* The users to set. OA} r*Wz
*/ 23,pVo
publicvoid setUsers(List users){ v9KsE2Ei
this.users = users; P&@,Z#\
} 7xux%:BN
A;&YPHB
/** /EegP@[
* @param userService _Y}cK|3
* The userService to set. 7&%HE\
*/ ab.B?bx
publicvoid setUserService(UserService userService){ \j BA4?(S
this.userService = userService; 0@y`iZ]
1S
} Q00v(6V46
} :("@U,
oe3=QE
l%?4L/J)#
ylS6D
guf*>qNr
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, Q
8;JvCz
Dfc%
jWbA
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 2+C:Em0yI
;4GGXT++L
么只需要: f4F%\ "
java代码: 19pFNg'kA
.5s^a.e'O
3c(mZ
<?xml version="1.0"?> Br42Qo2"T>
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Hi/[
V\e1NS
1.0//EN" "http://www.opensymphony.com/xwork/xwork- sX3qrRY
PX2b(fR8_O
1.0.dtd"> iWFtb)3B
>ke.ZZV?
<xwork> =YfzB!ld
j(K)CHH
<package name="user" extends="webwork- FUJ<gqL
/0fHkj/J=B
interceptors"> L%<]gJtrO
ZJF+./vN
<!-- The default interceptor stack name `g)
B*Om\I
--> H Vhd#Q;
<default-interceptor-ref UugR
K=}Eupn=
name="myDefaultWebStack"/> qbCU&G|)
f1elzANy
<action name="listUser" :PY6J}:
1CSGG'J]E
class="com.adt.action.user.ListUser"> ]\oT({$6B
<param 1;i|GXY:h
G-K{
name="page.everyPage">10</param> ^;9l3P{
<result =n_z `I
,oSn<$%/q
name="success">/user/user_list.jsp</result> qN9 ?$\
</action> F7nwVDc*
}A;YM1^$
</package> jt: *Y
4<)*a]\c5M
</xwork> Z#(Y%6[u
i "X" -)#
:F#^Q%-IS
7#oq|5
V[]Pya|s+
8O60pB;4
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 8bs' Ek{'o
kumo%TXB&
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。 *PB /I4>{
BS,EW
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 @g+v2(f2v
0=t2|,}
.J&89I]U
S'w}Ir
Y
9z*xS
我写的一个用于分页的类,用了泛型了,hoho 05\0g9
'irwecd8
java代码: `
"-P g5
4GeN<9~YS
t%5bDdo
package com.intokr.util; [e@m-/B
OI78wG
import java.util.List; j!oX\Y-: &
}Qe(6'l_
/** A:2CP&*
* 用于分页的类<br> ^,vFxN--q
* 可以用于传递查询的结果也可以用于传送查询的参数<br> !Fxn1Z,
* +]NpcE'
* @version 0.01 W&D{0 i`y
* @author cheng #R31VQwK5
*/ % WXl*
public class Paginator<E> { S1@r.z2L
privateint count = 0; // 总记录数 ,aBy1K
privateint p = 1; // 页编号 {hN<Ot
privateint num = 20; // 每页的记录数 !7Qj8YmS
privateList<E> results = null; // 结果 I|K!hQ"m
:oC;.u<*8
/** *8;<w~
* 结果总数 ' S,g3
*/ gzH;`,
publicint getCount(){ * a1q M?
return count; `k8j FB C
} }NGP!
x?u@
j7[
publicvoid setCount(int count){ S?a4IK
this.count = count; iC^91!<
} w`+-xT%
H.C*IL9
/** \w1',"l`
* 本结果所在的页码,从1开始 ?OoI63&
* Z)=S>06X Q
* @return Returns the pageNo. k\*?<g
*/ n5BD0q
publicint getP(){ t0v>J9
return p; 7r)]9_[(
} !O}e)t
9%3+\[s1
/** Ie=gI+2
* if(p<=0) p=1 K"5q387!
* 61&{I>~1
* @param p 7IkEud
*/ ht>/7.p]
publicvoid setP(int p){ $]}K ;
if(p <= 0) ;#IrHR*Bk
p = 1; K7(k_4
this.p = p; >hq{:m
} O'#;Ge/,
j%Z5[{!/,X
/** C2=PGq
* 每页记录数量 LikCIO
*/ matm>3n
publicint getNum(){ 4x4[
return num; h)j#?\KYm9
} 3vAP&i'I
<gH-`3J6
/** 0pW;H|h
* if(num<1) num=1 ]GCw3r(!
*/ 1|ddG010
publicvoid setNum(int num){ ot!m=s
if(num < 1) .V0fbHYTJ
num = 1; G?\eO&QG{"
this.num = num; Ex*{iJ;\
} {}iS5[H]
u8|CeA
/** I?%q`GyP5
* 获得总页数 Qy4Pw\
*/ ,WnZ^R/n
publicint getPageNum(){ '/9MN;_
return(count - 1) / num + 1; wxj}k7_(`A
} QfPw50N;
g+QIhur
/** `_ M+=*}
* 获得本页的开始编号,为 (p-1)*num+1 KU0Ad);e
*/ q(hBqU W
publicint getStart(){ 9kqR-T|Q
return(p - 1) * num + 1; fZsw+PSy
} OK`^DIr5l
PvjZoF["
/** `U\l: ~]e
* @return Returns the results. T3"'`Sd9;
*/ Z,O-P9jC
publicList<E> getResults(){ fz|_c*&64
return results; fGs\R]
} sMUpkU-
7F~g A74h
public void setResults(List<E> results){ ;qbK[3.
this.results = results; /k RCCs8t}
} 52Dgul
5A|dhw
public String toString(){ xt"-Jmox
StringBuilder buff = new StringBuilder ;1nXJ{jKw
{r|RH"|?Z(
(); 88[u^aC
buff.append("{"); Q!=`|X|:
buff.append("count:").append(count); 60A!Gob
buff.append(",p:").append(p); 4t/ ?b
buff.append(",nump:").append(num); h?B1Emlq
buff.append(",results:").append l. l)w
EowzEGq!a5
(results); _!Tjb^
buff.append("}"); <Uf`'X\e6
return buff.toString(); Cd]A1<6s
} a&)!zhVP
gE=9K @
} 8==M{M/eM
k W
8>VnW
2P@6Qe
?