Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 la^K|!|
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 gplrJaH@
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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[0CVWs,
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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"gX>e~
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分页支持类: QpS7nGev
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java代码: {*<%6?
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package com.javaeye.common.util; -e0?1.A$
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import java.util.List; vw-y:,5`t8
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publicclass PaginationSupport { x]4>f[>*>
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publicfinalstaticint PAGESIZE = 30; O]61guxro
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privateint pageSize = PAGESIZE; OgHqF,0MN
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privateList items; I\IDt~
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privateint totalCount; F4ylD5Y!
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privateint[] indexes = newint[0]; n{M-t@r7
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privateint startIndex = 0; jBd=!4n
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public PaginationSupport(List items, int k$kxw_N5d
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totalCount){ }
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setPageSize(PAGESIZE); S5YEz
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setTotalCount(totalCount); )lJi7 ^,
setItems(items); ]c]^(C
setStartIndex(0); 'Axe:8LA'
} t5 P8?q\
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public PaginationSupport(List items, int u}rJqZ
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totalCount, int startIndex){ 7Rc>LI*
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setPageSize(PAGESIZE); 6:Y2z!MLO
setTotalCount(totalCount); vjA!+_I6
setItems(items); @twi<U_
setStartIndex(startIndex); r>sXvzv
} \c!e_rZ
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public PaginationSupport(List items, int #<#-B v
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totalCount, int pageSize, int startIndex){ l j+p}dt
setPageSize(pageSize); m9\~dD
setTotalCount(totalCount); @CoUFdbz
setItems(items); Zb'a+8[
setStartIndex(startIndex); H;ujB \+
} j8^zE,Z
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publicList getItems(){ 1{1mL-I;
return items; ['3E'q,4&
} #nmh=G?\Sm
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publicvoid setItems(List items){ .
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this.items = items; CdtCxy5
} /-(OJN5F^
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publicint getPageSize(){ mXyg\5
return pageSize; Vo|[Z)MO`
} ~ftR:F|9
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publicvoid setPageSize(int pageSize){ 7loWqZ
this.pageSize = pageSize; V6k Dyl(
} ='-/JH~
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publicint getTotalCount(){ w@\4ft6d
return totalCount; Yjl:i*u/
} 8Au W>7_
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publicvoid setTotalCount(int totalCount){ 7f<@+&
if(totalCount > 0){ Ht@5@(W]I
this.totalCount = totalCount; *qxv"PptX
int count = totalCount / W*,$0 t
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pageSize; 3T[zieX
if(totalCount % pageSize > 0) czB),vooz
count++; F;Q'R|HQ
indexes = newint[count]; j(M.7Z7^
for(int i = 0; i < count; i++){ K~fWZT3]
indexes = pageSize * }Nma %6PfV
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} 5,\|XQA5!
}else{ PWO5R]
this.totalCount = 0; Q9Go}}n
} m6Qm }""
} Z|A+\#'
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publicint[] getIndexes(){ LKZv#b[h
return indexes; p}Bh
} Owv}lJ
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publicvoid setIndexes(int[] indexes){ JIf.d($
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this.indexes = indexes; [ fs.D /
} S %wdXe
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publicint getStartIndex(){ >LB*5
return startIndex; z$Qy<_l
} \3hFb,/4k
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publicvoid setStartIndex(int startIndex){ @ 0/EKWF
if(totalCount <= 0) GC(QV}9z"
this.startIndex = 0; #IJ6pg>K
elseif(startIndex >= totalCount) X +/^s)
this.startIndex = indexes \KKE&3=
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[indexes.length - 1]; <S12=<c?'
elseif(startIndex < 0) DU-dIqi
this.startIndex = 0; o@L
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else{ (?i4P5s[!
this.startIndex = indexes e488}h6#m
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[startIndex / pageSize]; |EY1$qItid
} &y-z[GR[{
} D}N4*L1
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publicint getNextIndex(){ db>"2EE
int nextIndex = getStartIndex() + klTRuU(
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pageSize; Oe;1f#`5
if(nextIndex >= totalCount) Fz5eCe\B
return getStartIndex(); *|gl1S
else P~PM $e
return nextIndex; f9O_M1=|lo
} =p dLh
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publicint getPreviousIndex(){ }n
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int previousIndex = getStartIndex() - (@bq@0g
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pageSize; 9Fg:
if(previousIndex < 0) ={jj'X9
return0; iEbW[sX[4
else 7Q~$&G
return previousIndex; *9`k$'
} A[^k4>
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} DW)X3A(^
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抽象业务类 gOp81)
java代码: a;&0u>
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/** om6`>I*
* Created on 2005-7-12 Vygh|UEo
*/ b$tf9$f
package com.javaeye.common.business; GKG:iR)
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import java.io.Serializable; qVvnl
import java.util.List; :j`XU
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import org.hibernate.Criteria; =!/T4Oo
import org.hibernate.HibernateException; jV<5GWq
import org.hibernate.Session; N5tFEV'G
import org.hibernate.criterion.DetachedCriteria; ]jR-<l8I-
import org.hibernate.criterion.Projections; Yfy";C7X
import QHtN_Q_F
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org.springframework.orm.hibernate3.HibernateCallback; fr8';Jm
import @[Wf!8_
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org.springframework.orm.hibernate3.support.HibernateDaoS GbvbGEG
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upport; V3/OKI\o
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import com.javaeye.common.util.PaginationSupport; =r&i`L{]
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public abstract class AbstractManager extends |_a^+!P
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HibernateDaoSupport { "Q{7X[$$^
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privateboolean cacheQueries = false; U?Vik
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privateString queryCacheRegion; T7 (d
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publicvoid setCacheQueries(boolean C\ 34R
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cacheQueries){ v(,YqT>q@U
this.cacheQueries = cacheQueries; {RD9j1
} "J`#
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publicvoid setQueryCacheRegion(String J@rBrKC
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queryCacheRegion){ D"{%[;J
this.queryCacheRegion = s1X?]A
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queryCacheRegion; X& XD2o"rt
} Q{~;4+ZD
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publicvoid save(finalObject entity){ B.);Ju
getHibernateTemplate().save(entity); g$z6*bL
} +Edq4QYwR
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publicvoid persist(finalObject entity){ p#>,{
getHibernateTemplate().save(entity); \^lDd~MWG
} !)`m mr
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publicvoid update(finalObject entity){ HLqDI lL
getHibernateTemplate().update(entity); )?(_vrc<
} SN$3cg]z
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publicvoid delete(finalObject entity){ yEVnG`
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getHibernateTemplate().delete(entity); <4I`|D3@
} E:P_CDSd]
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publicObject load(finalClass entity, k7 Ne(4P
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finalSerializable id){ On,z#A
return getHibernateTemplate().load Z/OERO
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(entity, id); ,X\qlT5C
} fyq%-Tj
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publicObject get(finalClass entity, ;rXZ?"
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finalSerializable id){ tHFUV\D;,
return getHibernateTemplate().get EIOP+9zP
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(entity, id); k?_uv
} k:&B
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publicList findAll(finalClass entity){ "}0)~,{xB
return getHibernateTemplate().find("from Ls&-8
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" + entity.getName()); Y{8}z
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} JRDIGS_~
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publicList findByNamedQuery(finalString /^`do3a}
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namedQuery){ o3le[6C/8=
return getHibernateTemplate DyRU$U
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().findByNamedQuery(namedQuery); =bQ\BY#
} Bey9P)_Of
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publicList findByNamedQuery(finalString query, gbu)bqu2x
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finalObject parameter){ 0 R>!jw
return getHibernateTemplate O#)YbaE
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().findByNamedQuery(query, parameter); hh-sm8
} 9Wdx"g52_D
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publicList findByNamedQuery(finalString query, -hGLGF??
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finalObject[] parameters){ w1+
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return getHibernateTemplate &InFC5A
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().findByNamedQuery(query, parameters); (^~~&/U_U$
} +y 48.5
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publicList find(finalString query){ ~{t<g;F
return getHibernateTemplate().find .nei9Y*
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(query); =@d->d
} _F2ofB'
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publicList find(finalString query, finalObject 5W09>C>OC
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parameter){ id>2G
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return getHibernateTemplate().find *^ua2s.
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(query, parameter); #eKH'fE
} "?'9\<>
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public PaginationSupport findPageByCriteria )1!0'j99.
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(final DetachedCriteria detachedCriteria){ ye4GHAm,p
return findPageByCriteria 4?c0rC<
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); <4-g2.\
} >|1-o;UU
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public PaginationSupport findPageByCriteria 9{-H/YS\_s
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(final DetachedCriteria detachedCriteria, finalint pzT`.#N:M
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startIndex){ u/J1Z>0
return findPageByCriteria tSVS ogGd
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(detachedCriteria, PaginationSupport.PAGESIZE, cEGR?4z
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startIndex); <lRjh7
} )~ ^`[`
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public PaginationSupport findPageByCriteria p uW
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(final DetachedCriteria detachedCriteria, finalint $NBQv6#:
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pageSize, ;S'1fci6
finalint startIndex){ x}O J~Yk]
return(PaginationSupport) ]ts^h~BZ$
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getHibernateTemplate().execute(new HibernateCallback(){ $|I hO
publicObject doInHibernate (XV+aQ \A
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(Session session)throws HibernateException { p & i+i
Criteria criteria = MSe>1L2=
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detachedCriteria.getExecutableCriteria(session); ]<u%jTQREd
int totalCount = cEK#5
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((Integer) criteria.setProjection(Projections.rowCount hcR^?
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()).uniqueResult()).intValue(); #r@>.S=U]
criteria.setProjection .i1|U8" X
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(null); p\tA&>3-
List items = "J2v8c
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criteria.setFirstResult(startIndex).setMaxResults }&^1")2t
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(pageSize).list(); BuOe'$F
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PaginationSupport ps = ;7(vqm<V2~
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new PaginationSupport(items, totalCount, pageSize, vg5fMH9ZZ
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startIndex); 07>D G#
return ps; -~
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} Q}1qt4xy*
}, true); -#r=
} |wyua@2
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public List findAllByCriteria(final }s.\B
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DetachedCriteria detachedCriteria){ A%~t[ H
return(List) getHibernateTemplate "P$')uwE
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().execute(new HibernateCallback(){ lN_b&92
publicObject doInHibernate gj82qy\:
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(Session session)throws HibernateException { J5}?<Dd:
Criteria criteria = Z*.rv t
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detachedCriteria.getExecutableCriteria(session); +#6f)H(P]
return criteria.list(); R xc
} ONLhQJCb
}, true); M[L@ej
} g>{t>B%v^K
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public int getCountByCriteria(final kE1k@h#/
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DetachedCriteria detachedCriteria){ (i-L:
Integer count = (Integer) srH.$Y;~
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getHibernateTemplate().execute(new HibernateCallback(){ ZpZoOdjslV
publicObject doInHibernate NFI~vkk'G
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(Session session)throws HibernateException { a)!R4
Criteria criteria = (mx}6A
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detachedCriteria.getExecutableCriteria(session); 9 $zx<O
return
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criteria.setProjection(Projections.rowCount ?]>;Wr
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()).uniqueResult(); O)`ye5>v
} \4uj!LgTb
}, true); 8cj}9}k
return count.intValue(); ngzQVaB9
} GZ.KL!,R!
} cpx:4R,
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用户在web层构造查询条件detachedCriteria,和可选的 unyU|B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 y~wN:
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PaginationSupport的实例ps。 Q>uJ:[x+
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ps.getItems()得到已分页好的结果集 kuv+ TN
ps.getIndexes()得到分页索引的数组 1z@{4)
ps.getTotalCount()得到总结果数 S*H
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ps.getStartIndex()当前分页索引 \_/dfmlIZ
ps.getNextIndex()下一页索引 MFqb_q+
ps.getPreviousIndex()上一页索引 3*oZol/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 GsIqUM#R
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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 yRt7&,}zL
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一下代码重构了。 ?F|F~A8dr
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我把原本我的做法也提供出来供大家讨论吧: Om2w+yU
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首先,为了实现分页查询,我封装了一个Page类: O?iLLfs
java代码: H )Ze{N
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/*Created on 2005-4-14*/ |^gnT`+
package org.flyware.util.page; m5cRHo<9Y
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/** ]i8t
* @author Joa .v['INK9
* o RK:{?Y
*/ %t]{C06w+{
publicclass Page { Z5[g[Q
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/** imply if the page has previous page */ yER
privateboolean hasPrePage; Eopb##o
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/** imply if the page has next page */ z]!w@:
privateboolean hasNextPage; i ~rb-~o
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/** the number of every page */ dHtEyF
privateint everyPage; +_ny{i`'
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/** the total page number */ fD%20P`.
privateint totalPage; 2j$~lI
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/** the number of current page */ )oZ2,]us!
privateint currentPage; ?B<.d8i
Myh?=:1~(c
/** the begin index of the records by the current f\H1$q\p\
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query */ 1eI_F8I U
privateint beginIndex; &a'LOq+r'
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/** The default constructor */ @I?:x4
public Page(){ HP:[aR!2P
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} D{JwZL@7k2
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/** construct the page by everyPage ~Jlq.S'
* @param everyPage =:\5*
* */ SA?1*dw)
public Page(int everyPage){ =D)ADZ\<r
this.everyPage = everyPage; T2|os{U
} Us% _'}(/U
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/** The whole constructor */ KIY9?B=+
public Page(boolean hasPrePage, boolean hasNextPage, o 9d|XY_
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int everyPage, int totalPage, _.SpU`>/f
int currentPage, int beginIndex){ [<nd+3E
this.hasPrePage = hasPrePage; )-25?B
this.hasNextPage = hasNextPage; `tl -] ^Y2
this.everyPage = everyPage; BqtN=
this.totalPage = totalPage; p:3w8#)MZ
this.currentPage = currentPage; wcGv#J],
this.beginIndex = beginIndex; n/YnISt
} ulfs Z:
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/** 6sT(t8[
* @return Y[W]YPs
* Returns the beginIndex. JX`>N(K4\
*/ BJ{?S{"6%G
publicint getBeginIndex(){ *?+2%zP
return beginIndex; N:,V{Pw
} k;r[m,$
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/** (iht
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* @param beginIndex h;~NA}>
* The beginIndex to set. 1G'pT$5&
*/ co'qVsOiH
publicvoid setBeginIndex(int beginIndex){ "e/"$z'ca
this.beginIndex = beginIndex; =`l><
} "+hUt
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/** \jAI~|3
* @return $paE6X^
* Returns the currentPage. m3XT8F*&
*/ (Z8wMy&:
publicint getCurrentPage(){ ed#>q;jX
return currentPage; S(0JBGC
} 7mL1$i6=
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/** .GWN~iR(
* @param currentPage Hio+k^
* The currentPage to set. ](`:<>c
*/ AG"iS<u
publicvoid setCurrentPage(int currentPage){ pqe%tRH{
this.currentPage = currentPage; FA;B:O@:'
} JvS
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/** bnV)f<
* @return TJuS)AZ
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* Returns the everyPage. /mwDVP<z /
*/ S5~(3I
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publicint getEveryPage(){ a~zh5==QD
return everyPage; D3y4e8+Z'
} MI~QXy,
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/** R9UC0D:-x
* @param everyPage V=c?V/pl
* The everyPage to set. <ILi38%Y
*/
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publicvoid setEveryPage(int everyPage){ #*3 vE& p
this.everyPage = everyPage; p$<){,R
} ,? Q1JZPy@
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/** /K_*Drk>
* @return 01IfvK
* Returns the hasNextPage. Gi&/`vm
*/ (V"7H
publicboolean getHasNextPage(){ @9\E
return hasNextPage; EdZNmL3cB
} z]j_,3Hff
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/** HN<e)E38
* @param hasNextPage ?yA
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* The hasNextPage to set. _V` QvnT}
*/ WrR8TYq9D]
publicvoid setHasNextPage(boolean hasNextPage){ {(h!JeQ
this.hasNextPage = hasNextPage; 7*4i0{]
} <lWBhrz
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/** x_= 3!)
* @return A64c,Uv
* Returns the hasPrePage. h9rrkV9
*/ ,u14R]
publicboolean getHasPrePage(){ uC2 5pH"
return hasPrePage; +\J+?jOC4S
} .C1g Dry]
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/** #?~G\Ux0/
* @param hasPrePage ,Uy~O(Ft
* The hasPrePage to set. sO)!}#,
*/ zhU^~4F
publicvoid setHasPrePage(boolean hasPrePage){ g5
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this.hasPrePage = hasPrePage; ^;@!\Rc
} vQ[ TcV
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/** e{.P2rnh
* @return Returns the totalPage. xP 3>8Y
* SnoEi~Da
*/ ,;yaYF6|/
publicint getTotalPage(){ t<cWMx5ra
return totalPage; ?y^ ix+M
} IOl0=+p
f1t?<=3Ek<
/** !KHbsOT?9
* @param totalPage ;\iu*1>Z,&
* The totalPage to set. @! jpJ}
*/ Y }8HJTMB
publicvoid setTotalPage(int totalPage){ 2-:` lrVd
this.totalPage = totalPage; Bhe0z|&
} B:)vPO+ d
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} RR>G}u9np
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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 dz?Ey~;M
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个PageUtil,负责对Page对象进行构造: ^1XnnQa
java代码: ~bfjP2
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/*Created on 2005-4-14*/ ZMch2 U8
package org.flyware.util.page; 5WI0[7
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import org.apache.commons.logging.Log; D+*_iM6[-
import org.apache.commons.logging.LogFactory; K Z0%J5
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/** u6*mHkM
* @author Joa ['l}*
* !3o]mBH8
*/ Y+3r{OI
publicclass PageUtil { wodff_l
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privatestaticfinal Log logger = LogFactory.getLog 5I5#LQv0
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(PageUtil.class); ae]
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/** 1i
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* Use the origin page to create a new page =7zvp,B
* @param page
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* @param totalRecords ]$A6krfh|
* @return E D_J8+
*/ </qli-fXB}
publicstatic Page createPage(Page page, int J8hH#7WMS
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totalRecords){ =z2g}X
return createPage(page.getEveryPage(), ]ov"&,J
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page.getCurrentPage(), totalRecords); BEii:05
} !:|D[1m
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/** 0,m@BsK
* the basic page utils not including exception AkBEE
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handler |A:+[35
* @param everyPage "@&I*1&
* @param currentPage YGkk"gFIA
* @param totalRecords L(3}
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* @return page 9jrlB0
*/ IaRq6=[
publicstatic Page createPage(int everyPage, int 50`<[w<J
q
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currentPage, int totalRecords){ vv`,H~M6
everyPage = getEveryPage(everyPage); K$~Ja
currentPage = getCurrentPage(currentPage); =%d0MZD
int beginIndex = getBeginIndex(everyPage, W
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currentPage); [f-<M@id/
int totalPage = getTotalPage(everyPage, 3?yq*uE}
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totalRecords); c +]5[6
boolean hasNextPage = hasNextPage(currentPage, +q)B4A'J!
EP]O J$6I
totalPage); l1}HJmom
boolean hasPrePage = hasPrePage(currentPage); o%?~9rf]]
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returnnew Page(hasPrePage, hasNextPage,
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everyPage, totalPage, YN5p@b=FX
currentPage, __,}/|K2
@m ?&7{y#?
beginIndex); -wn(J5NnR
} Xq.GvZS`
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privatestaticint getEveryPage(int everyPage){ YX6[m6LU
return everyPage == 0 ? 10 : everyPage; F$>^pw
} RyN?Sn5)
;NrU|g/ksX
privatestaticint getCurrentPage(int currentPage){ "pkn
return currentPage == 0 ? 1 : currentPage; x-ZCaa}O
} c!>",rce
T\$r|
privatestaticint getBeginIndex(int everyPage, int oA$]%
H%`|yUE(
currentPage){ /mFa*~dj2
return(currentPage - 1) * everyPage; g+92}$_
} vhu5w#]u*
~JxAo\2i
privatestaticint getTotalPage(int everyPage, int #kL4Rm;
B}2 JK9
totalRecords){ Km,:7#aV
int totalPage = 0; St~a/Lq6
`1)n2<B
if(totalRecords % everyPage == 0) 7%Ii:5Bp
totalPage = totalRecords / everyPage; (% f2ZNen
else (= ,w$
totalPage = totalRecords / everyPage + 1 ; rQD7ZN_ R
ttC+`0+H
return totalPage; ~:lN("9OI
} }e0)=*;l
Zk75GC
privatestaticboolean hasPrePage(int currentPage){ P*sb@y>}O
return currentPage == 1 ? false : true; 334tg'2]
} dEM=U;
iWu^m+"k
privatestaticboolean hasNextPage(int currentPage, rJ}k!}G
i2+vUl|;Z
int totalPage){ 5$p7y:
return currentPage == totalPage || totalPage == ]NgEN
Hze~oAP+
0 ? false : true; ]R s
} h>A}vI*:
c<j+"
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} by%k*y
Cz1o@rt
%O_Ed
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+~]LvZtI_
~J,e^$u
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。 ^N_ ?&pgy
[EU\-
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 CNF3".a
#9)D.d|5
做法如下: $f]dL};
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 YXWlg%s
~g[<A?0=y
的信息,和一个结果集List: 8rA?X*|S!
java代码: &WGG
kn
m^Xq<`e"<
`jyBF
/*Created on 2005-6-13*/ pJ 7="n
package com.adt.bo; >rb8A6
2pQdDbm
import java.util.List; Jv9yy~
W6[# q%o
import org.flyware.util.page.Page; z?i{2Fz6
X6g{qz Hg_
/** V}UYr Va#9
* @author Joa !K$qh{n
*/ />\6_kT
publicclass Result { K<Qy1y~[
>*aqYNft
private Page page; 9F^rXY.
El)WjcmH
private List content; G*lkVQ6?
SYsbe 5j
/** !Cv:,q
* The default constructor NN;'QiE
*/ ]aF!0Fln~
public Result(){ 79JU
super(); f.&((z?rC
} IJt8*
cw
d*{NAq'9X
/** -N]%)Hy
* The constructor using fields l
/\n7:
* M;Dk$B{;R
* @param page HQOz
* @param content '6&a8&:
*/ 9s}y*Vp
public Result(Page page, List content){ B Ctm05
this.page = page; j\S}TaH0e
this.content = content; };=44E'7
} CnA0^JX
AT%@T|
/** 4Cdl^4(LT
* @return Returns the content. !{,
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*/ pNzSy"Y$
publicList getContent(){ IT\lkF2
return content;
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} ?QXc,*=N
O~WT$
/** lZa L=HS#L
* @return Returns the page. c/q -WEKL
*/ m|5yET
public Page getPage(){ w0FkKJV
return page; $J]b+Bp
} X^;LiwQv
oI6l `K$
/** T+y3Ph--^
* @param content aA5rvP+
* The content to set. 09psqXU@I
*/ @a{1vT9b
public void setContent(List content){ N$i|[>`j
this.content = content;
`>mT/Rmb@
} LYv$U;*+
hD5G\TR.
/** mSu1/?PS
* @param page rcWr0q
* The page to set. Jm l4EW7
*/ (\=iKE4#
publicvoid setPage(Page page){ OYsG#
this.page = page; M!e$h?vB
} n
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} j5yxdjx9
6fOh *
H[a1n' "<:
^l(Kj3gM
"7*cF>FE 8
2. 编写业务逻辑接口,并实现它(UserManager, Mk -Rl
#~SQujgB
UserManagerImpl) vQ/&iAyut
java代码: Xt!%W
8=%%C:
zu~E}
/*Created on 2005-7-15*/ wSMP^kG
package com.adt.service; /5y*ZIq]e
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import net.sf.hibernate.HibernateException; >,Zf3M
V>`xTQG
import org.flyware.util.page.Page; vl'2O7
%0z&k!P
import com.adt.bo.Result; SbLx`]rI
#$GDKK
/** :$`"M#vMX
* @author Joa `]{/(pIgW;
*/ !\0UEC
publicinterface UserManager { )aOPR|+
HktvUJ(Ii
public Result listUser(Page page)throws -|l^- Qf!
-2dk8]KB]
HibernateException; <3;Sq~^
) DzbJ}
} Fj`6v"h
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=psX2?%L
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java代码: kAEm#oz=g
xt%-<%s %f
4EO,9#0
/*Created on 2005-7-15*/ U2DE"
package com.adt.service.impl; YmS}*>oz
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import java.util.List; ]&')#YO
Ighd,G-
import net.sf.hibernate.HibernateException; bk**% ]
[_&\wHX
import org.flyware.util.page.Page; 1?6;Oc^
import org.flyware.util.page.PageUtil; [HKTXF{n
i U^tv_1
import com.adt.bo.Result; <4gT8kQ$x
import com.adt.dao.UserDAO; .."=
import com.adt.exception.ObjectNotFoundException; ;BsPms@U
import com.adt.service.UserManager; RN0@Q~oTI
@c<*l+Qc
/** BnLM ;5
>
* @author Joa ?(&)p~o
*/ VPB,8zb]
publicclass UserManagerImpl implements UserManager { bN6FhKg|
cI9} YSk
private UserDAO userDAO; ~v2E<S3
<mm.b
/** ^MyuD?va
* @param userDAO The userDAO to set. M>pcG.6V
*/ !);kjXQS?
publicvoid setUserDAO(UserDAO userDAO){ ]vJ]
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this.userDAO = userDAO; J!$q"0G'WT
} Fu*~{n
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/* (non-Javadoc) hcvWf\4'#q
* @see com.adt.service.UserManager#listUser t,*hxzD"
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(org.flyware.util.page.Page) &TmN^R>
*/ #PzRhanX
public Result listUser(Page page)throws p nS{W
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HibernateException, ObjectNotFoundException { E1U~ew
int totalRecords = userDAO.getUserCount(); A8?uCkG
if(totalRecords == 0) &*wN@e(c
throw new ObjectNotFoundException @O7hY8",
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("userNotExist"); q;dg,Om
page = PageUtil.createPage(page, totalRecords); wt;7+
List users = userDAO.getUserByPage(page); w&eX)!
returnnew Result(page, users); vjy 59m
} yw|O,V<4N
d]JiJgfa%
} %1uY
hrpql_9.
#S57SD
2qY`*Y.2
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 0] 'Bd`e
XwKB+Yj0
询,接下来编写UserDAO的代码: r sf +dC
3. UserDAO 和 UserDAOImpl: ]V,wIyC
java代码: Sga/i?!
nATEv2:G
Voi`OCut
/*Created on 2005-7-15*/ fdIO'L_
package com.adt.dao; > .L\ >
1 m)WM,L
import java.util.List; gpB pG
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import org.flyware.util.page.Page; UN7>c0B
g1JBssw&m
import net.sf.hibernate.HibernateException; }B=`nbgIG7
_raj
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/** n%o"n?e
* @author Joa lx8@;9fLy
*/ B'( /W@
publicinterface UserDAO extends BaseDAO { O7p>"Bh
c#?JW:^|Df
publicList getUserByName(String name)throws j'#Y$d1.
H"_ZqEg
HibernateException; :zXkQQD8`
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publicint getUserCount()throws HibernateException; kW"6Gc&HUN
;++CMTza]
publicList getUserByPage(Page page)throws 5&WYL
).[Mnt/Ft
HibernateException; (^fiw%#
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} W7k\j&x
1+1Z]!nG#!
"0JG96&\
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7^}np^[HB
java代码: 2f'3Vjp~G
| |=q"h3(
&tT*GjPwg;
/*Created on 2005-7-15*/ ?lg
package com.adt.dao.impl; w)A@
fiuF!<#;6
import java.util.List; ys+ AY^/
GCn^+`.h1t
import org.flyware.util.page.Page; `:hEc<_/
1]wx Ru
import net.sf.hibernate.HibernateException; ?[n{M
import net.sf.hibernate.Query; }bQqln)#
ku=o$I8K
import com.adt.dao.UserDAO; J7FCW^-`3
B3Id}[V
/** Xr54/.{&@
* @author Joa fAHK<G4
*/ f>LwsP
public class UserDAOImpl extends BaseDAOHibernateImpl '~2S BX?J
02U5N(s
implements UserDAO { Z x9oj
dd+[FU
/* (non-Javadoc) =YZyH4eI
* @see com.adt.dao.UserDAO#getUserByName 1Ner1EKGp
u)]]9G
_8
(java.lang.String) Z83A1`!.|
*/ RcQo1
publicList getUserByName(String name)throws !&f(Xs
vYT%e:8)q
HibernateException { Nqih LUv
String querySentence = "FROM user in class =|lw~CW
k 7 !{p
com.adt.po.User WHERE user.name=:name"; 4CR.=
Query query = getSession().createQuery {0J TN%e
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[
(querySentence); :JBvCyj4PE
query.setParameter("name", name); Qqt<
return query.list(); %nU8 Ca
} QLx]%E\
s bf\;_!
/* (non-Javadoc) *h=|KOS
* @see com.adt.dao.UserDAO#getUserCount() Ep/kb-~-
*/ [nQ<pTg~r
publicint getUserCount()throws HibernateException { N1dp%b9W(
int count = 0; 9cJzL"yi
String querySentence = "SELECT count(*) FROM y'ZRoakz)
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user in class com.adt.po.User"; Z)RoFD1]C
Query query = getSession().createQuery SDY!! .
NXQdy g,
(querySentence); y:TLGQ0
count = ((Integer)query.iterate().next JTH8vk:@
Jvysvi{8
()).intValue(); %G~f>
return count; cN/8b0C
} =c{/ Z
Jh3(5d"MV
/* (non-Javadoc) !<psK[
* @see com.adt.dao.UserDAO#getUserByPage sq6|J])GgU
"xS?#^a
(org.flyware.util.page.Page) `(j}2X'[
*/ Hu"?wZj
publicList getUserByPage(Page page)throws 2Z3c` /k
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HibernateException { &yFt@g]
String querySentence = "FROM user in class ~(2G7x)
&"v h=Z-
com.adt.po.User"; "Dbjp5_
Query query = getSession().createQuery 0E9LZOw4T
Mz}yf5{f
(querySentence); -5 -X[`cF
query.setFirstResult(page.getBeginIndex()) S`yY<1[O
.setMaxResults(page.getEveryPage()); N
O|&nqq,>
return query.list(); ]YF[W`2h
} YG<7Zv
_<?lP$Xr
} <^}{sdOyu
VH&6Tm1
^P&)2m:s
Z!Y ^iN
pgK)
至此,一个完整的分页程序完成。前台的只需要调用 V\nQHzjF<6
-3 }
userManager.listUser(page)即可得到一个Page对象和结果集对象 +we3BE.
@pueM+(L&
的综合体,而传入的参数page对象则可以由前台传入,如果用 b"-eQb
p #:.,;
webwork,甚至可以直接在配置文件中指定。 b[<Q_7~2
v#EXlpS
下面给出一个webwork调用示例: =i jGB~
java代码:
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<;
$i@~$m7d-
s'yA^
VPf
/*Created on 2005-6-17*/ $xT'cl/IH
package com.adt.action.user; ] -O/{FIv
xviz{M9g
import java.util.List; wy3{>A Z(
ADoxma@
import org.apache.commons.logging.Log; oi4tj.!J
import org.apache.commons.logging.LogFactory; *c} MI
e'&
import org.flyware.util.page.Page; D{~mJDUzK
9o7E/wP
import com.adt.bo.Result; Rn={:u4
import com.adt.service.UserService; jBexEdH
import com.opensymphony.xwork.Action; MqXN,n+`k
SooSOOAx[
/** Z/=x(I0
* @author Joa m09
Bds
*/ {b4+ Yc
publicclass ListUser implementsAction{ (dO, +~
Rg! [ic !
privatestaticfinal Log logger = LogFactory.getLog g`)2I+L7
.@{W6
/I
(ListUser.class); 9N^&~O|1
zItf>j7|Z
private UserService userService; $_,?SXM
SdF*"]t
private Page page; so h3d
7[)4k7
privateList users; ,}%+5yH
2lw0'
/* D.G+*h@ g
* (non-Javadoc) a@_.uD
* #7OUqp
* @see com.opensymphony.xwork.Action#execute() { Z<4
*/ F5Tah{
publicString execute()throwsException{ b?U!<s.
Result result = userService.listUser(page); %H\i}}PTe
page = result.getPage(); lUXxpv1m
users = result.getContent(); U[9`:aV;
return SUCCESS; aagN-/mgm
} Cs$wgm*
l_JPkM(mJw
/** pNFL;k+p}
* @return Returns the page. 56(S[
*/ Y=JfV
public Page getPage(){ Nq>74q]}n8
return page; Ct[{>asun
} xcO Si>
&mj98
/** H:x=v4NgsU
* @return Returns the users. b!VaEK
*/ +o)o4l%3
publicList getUsers(){ E.kGBA;a?
return users; MH|!tkW>:
} ES72yh]
FJl#NOp&
/** _1[5~Pnh
* @param page (C/2shr 8
* The page to set. ON~jt[
*/ 9J%
~?k
publicvoid setPage(Page page){ @]u nqCO
this.page = page; H8j#rC#&pm
} !gv/ jdF
#)`N
/** X
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* @param users Y85M$]e,
* The users to set. <^+~?KDZM
*/ H)S&sx#q]
publicvoid setUsers(List users){ iTi]D2jC
this.users = users; `Y`Ujr\6
} n2\;`9zm
1t{h)fwi
/** e_6VPVa
* @param userService (i4=}Kn2
* The userService to set. .XR`iXY
*/ YX38*Ml+V
publicvoid setUserService(UserService userService){ dXgj
this.userService = userService; zk8s?$
} e
W&;r&26
} gZ6]\l]J{
uev$5jlX
/Y("Q#Ueq
)`?Es8uW
+$M%"=tk
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, qQC<oR
wzhM/Lmo\z
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 :eqDEmr>
\"B oTi'2!
么只需要: /*J}7
java代码: is K~=
fNOsB^Y
t b5k|
<?xml version="1.0"?> kW>Q9Nc=V
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork z+5l:f
~[bS+]d!
1.0//EN" "http://www.opensymphony.com/xwork/xwork- i{zg{$ U
BG!;9Z{u
1.0.dtd"> M^I*;{w6i
\},="
<xwork> )3g7dtq}
jH26-b<
<package name="user" extends="webwork- ,Oojh;P_
&