Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 V7.EDE2A3
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 '/mwXvl
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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 8{'L:yzMY
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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 Q\}5q3
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分页支持类: }oU0J
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java代码: i0hF9M
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package com.javaeye.common.util; ?EdF&^[3rD
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import java.util.List; x5s Yo\
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publicclass PaginationSupport { >%t"VpvR
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publicfinalstaticint PAGESIZE = 30; ,_HVPE
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privateint pageSize = PAGESIZE; sdrALl;w|
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privateList items; +n7bbuxj(X
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privateint totalCount; d(<[$3.
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privateint[] indexes = newint[0]; +eQg+@u
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privateint startIndex = 0; !CUrpr/*
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public PaginationSupport(List items, int Q!WXFS
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totalCount){ B\`4TU}kE
setPageSize(PAGESIZE); 4vF1
setTotalCount(totalCount); UH2fP G
setItems(items); rz5AIe>Hm
setStartIndex(0); Cjdw@v0;
} 7xqTTN6h
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public PaginationSupport(List items, int JHBX'1GQa
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totalCount, int startIndex){ um~U_&>
setPageSize(PAGESIZE); T|[zk.8=E
setTotalCount(totalCount); <7-3j{065
setItems(items); 4vC
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setStartIndex(startIndex); gy0l@ 5 N
} [BWA$5D)Ny
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public PaginationSupport(List items, int Dm2&}{&K
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totalCount, int pageSize, int startIndex){ Z$"E|nRN
setPageSize(pageSize); qX>mOW^gT8
setTotalCount(totalCount); !/2uO5
setItems(items); d?)k<!fJk
setStartIndex(startIndex); M|xd9kA^
} <'f+nC=2
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publicList getItems(){ MF69n,(o
return items; i|2CZ
} =f4>vo}@k
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publicvoid setItems(List items){ VXX7Y?!
this.items = items; 8cI<~|4_
} _HjS!(lMk
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publicint getPageSize(){ #l2KJ7AMK
return pageSize; m`_s_#
} cgY+xd@
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publicvoid setPageSize(int pageSize){ /{il;/Vj
this.pageSize = pageSize; O7vJ`K(!
} h'%iY6!fA
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publicint getTotalCount(){ 6ZKSet8
return totalCount; kbu.KU+
} 4;_aFn
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publicvoid setTotalCount(int totalCount){ Ls51U 7
if(totalCount > 0){ l7vU{Fd-h^
this.totalCount = totalCount; X!6oviT|m
int count = totalCount / re[v}cB
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pageSize; l<X8Ooan#{
if(totalCount % pageSize > 0) =zBc@VTp
count++; c{4Y?SSx
indexes = newint[count]; Y~,ZBl,
for(int i = 0; i < count; i++){ HFlMx
indexes = pageSize * ^I! u H1G
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} Oc A;+}>
}else{ /fh[_!qN
this.totalCount = 0; 'wA4}f
} @
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} I.'(n8*
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publicint[] getIndexes(){ K%i9S;~
return indexes; `YL)[t? V
} +s$` kl
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publicvoid setIndexes(int[] indexes){ T*pcS'?'
this.indexes = indexes; ,.6)y1!
} :^bjn3b
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publicint getStartIndex(){ ZF@T,i9
return startIndex; dkUh[yo"H
} 8>4@g!9E
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publicvoid setStartIndex(int startIndex){ e:`d)GE
if(totalCount <= 0) #" &<^
this.startIndex = 0; %0&c0vT
elseif(startIndex >= totalCount) u/6b.hDO
this.startIndex = indexes ^VL",Nt
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[indexes.length - 1]; 0Tp,b (;n
elseif(startIndex < 0) 3+~m 9:9
this.startIndex = 0; L>@:Xo@
else{ `%@|sK2
this.startIndex = indexes 2,T^L(]
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[startIndex / pageSize]; + 0DPhc
} @T 5dPmn
} o%j[]P@4G
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publicint getNextIndex(){ #I
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int nextIndex = getStartIndex() + w%' 8bH!
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pageSize; LWX,u
if(nextIndex >= totalCount) 5oOF|IYi
return getStartIndex(); I
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else iCXKi7
return nextIndex; RvXK?mL4F
} vHmsS\\~9
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publicint getPreviousIndex(){ .G/>X%X
int previousIndex = getStartIndex() - MdKkj[#
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pageSize; og$%`o:{
if(previousIndex < 0) jXH?os%
return0; hAi`2GP.
else CO5>Q o
return previousIndex; -5X*y4#
} a]]>(Txc
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抽象业务类 SSrYFu"
java代码: 8n2MZ9p]
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/** %D_pTD\
* Created on 2005-7-12 0r/pZ3/
*/ z
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package com.javaeye.common.business; DMXm$PU4V
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import java.io.Serializable; \g;o9}@3~
import java.util.List; y/9aI/O'
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import org.hibernate.Criteria; ZvVrbj&
import org.hibernate.HibernateException; %4#Q3YlyD
import org.hibernate.Session; *f ;">(`o*
import org.hibernate.criterion.DetachedCriteria; 3*<?'O7I0
import org.hibernate.criterion.Projections; 9V/:1I0?&0
import vj#Y /B
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org.springframework.orm.hibernate3.HibernateCallback; A8jj]J+
import NW%u#MZ[h
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org.springframework.orm.hibernate3.support.HibernateDaoS Bsc
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upport; @o/126(k
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import com.javaeye.common.util.PaginationSupport; 7FBaN7l
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public abstract class AbstractManager extends 2Y-NxW^]
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HibernateDaoSupport { }bA@QEJ
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privateboolean cacheQueries = false; ?nc:B]=pTY
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privateString queryCacheRegion; B{6wf)[O
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publicvoid setCacheQueries(boolean +[_mSt
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cacheQueries){ &CcUr#|
this.cacheQueries = cacheQueries; s%OPoRE
} \LbBK ~l-I
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publicvoid setQueryCacheRegion(String 1RM@~I$0
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queryCacheRegion){ Ng 3r`S"_<
this.queryCacheRegion = 2M`:/ shq
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queryCacheRegion; >u=Dc.lX
} tX'2 $}
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publicvoid save(finalObject entity){ KP*cb6vA
getHibernateTemplate().save(entity); +J;T= p
} [5T{`&
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publicvoid persist(finalObject entity){ F15Yn
getHibernateTemplate().save(entity); &4}Uaxt)
} 8H7=vk+
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publicvoid update(finalObject entity){ 8Ts_;uId
getHibernateTemplate().update(entity); g*-%.fNA
} N:%
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publicvoid delete(finalObject entity){ Z6\H4,k&
getHibernateTemplate().delete(entity); 24b?6^8~k
} U5!~@XjG>
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publicObject load(finalClass entity, q:a-tdv2
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finalSerializable id){ !QXPn}q^0
return getHibernateTemplate().load {I^@BW-
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(entity, id); n=1_- )
} -Ed<Kl
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publicObject get(finalClass entity, b2vCr F;
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finalSerializable id){ G W@g
return getHibernateTemplate().get EH~t<
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(entity, id); mR3-+dB/
} s1kG:h2|$
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publicList findAll(finalClass entity){ A(v5VvgZE
return getHibernateTemplate().find("from {1Hs5bg@
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" + entity.getName()); EZb_8<DH
} *i,@d&J y]
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publicList findByNamedQuery(finalString TRzL":
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namedQuery){ e,8[fp-7
return getHibernateTemplate 3z~d7J
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().findByNamedQuery(namedQuery); Zog&:]P'F
} !E.CpfaC
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publicList findByNamedQuery(finalString query, ic=tVs
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finalObject parameter){ &|Cd1z#?
return getHibernateTemplate $ts1XIK%
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().findByNamedQuery(query, parameter); HY>zgf,0
} ?Jy/]j5fI
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publicList findByNamedQuery(finalString query, W\1V`\gF
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finalObject[] parameters){ 0/TP`3$X#"
return getHibernateTemplate ({!S!k
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().findByNamedQuery(query, parameters); YDWV=/
} `x:8m?q05
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publicList find(finalString query){ )Rc
return getHibernateTemplate().find &qMt07
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(query); >j6"\1E+Dz
} #dhce0m
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publicList find(finalString query, finalObject pSKwXx
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parameter){ 5v_vv'~
return getHibernateTemplate().find M"!{Dx~
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(query, parameter); hUP?r/B
} d3jzGJrU}
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public PaginationSupport findPageByCriteria p:?h)'bA<
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(final DetachedCriteria detachedCriteria){ `NB6Of*/
return findPageByCriteria w0&|8y
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); =x3T+)qCNX
} `;HZO8
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public PaginationSupport findPageByCriteria ln*jak RrC
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(final DetachedCriteria detachedCriteria, finalint PTP0 _|K
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startIndex){ GWW#\0*Bn
return findPageByCriteria a%*W(
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(detachedCriteria, PaginationSupport.PAGESIZE, |*>s%nF|
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startIndex); b"pN; v
} /C6$B)w_*{
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public PaginationSupport findPageByCriteria HyYol*
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(final DetachedCriteria detachedCriteria, finalint z*e`2n#\
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pageSize, `b*x}HP$
finalint startIndex){ M~l\rg8
return(PaginationSupport) vn1*D-?
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getHibernateTemplate().execute(new HibernateCallback(){ r,Tq";N'
publicObject doInHibernate }DFZ9,gQ
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(Session session)throws HibernateException { AYsiaSTRqW
Criteria criteria = u3C0!{v
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detachedCriteria.getExecutableCriteria(session); Y,M2D
int totalCount = b NR@d'U
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((Integer) criteria.setProjection(Projections.rowCount /RemLJP
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()).uniqueResult()).intValue(); &xE+PfX
criteria.setProjection s8+{##"1
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(null); jZR2Nx}16
List items = v9MliD'
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criteria.setFirstResult(startIndex).setMaxResults +ux170Cd3
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(pageSize).list(); %@^9(xTE
PaginationSupport ps = Pf#DBW*
q'KXn0IY#
new PaginationSupport(items, totalCount, pageSize, DbrK,'b%
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startIndex); 4P=)u}{]^#
return ps; d~;U-
} KvmXRf*z
}, true); HE@P<
} 6ANAoWg*
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public List findAllByCriteria(final 9)J)r\
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DetachedCriteria detachedCriteria){ 91|~KR)
return(List) getHibernateTemplate %
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().execute(new HibernateCallback(){ IeAUVRS)
publicObject doInHibernate Xu& v3Y~k
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(Session session)throws HibernateException { =~q Xzq
Criteria criteria = UQnv#a>
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detachedCriteria.getExecutableCriteria(session); d(F4-kBd
return criteria.list(); :~\ y<
} p!7(ayu
}, true); Voo_
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} N{?Qkkgx
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public int getCountByCriteria(final VWW(=j
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DetachedCriteria detachedCriteria){ ,B$e'KQ
Integer count = (Integer) 7'RU\0QG
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getHibernateTemplate().execute(new HibernateCallback(){ /vAA]n8
publicObject doInHibernate &Vbcwv@
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(Session session)throws HibernateException { ~' q&rvk`
Criteria criteria = kY#sQz}8
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detachedCriteria.getExecutableCriteria(session); b X4]/4%
return lB(P+yY,/'
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criteria.setProjection(Projections.rowCount /Y8{?
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()).uniqueResult(); B+lnxr0t
} gsVm)mkd
}, true); [-h=L
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return count.intValue(); [-2Tj)P
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} .83z =
} k@Bn}r
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用户在web层构造查询条件detachedCriteria,和可选的 ]?V2L`/
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 !uN_<!
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PaginationSupport的实例ps。 z6'l" D'h
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ps.getItems()得到已分页好的结果集 DHh30b$c
ps.getIndexes()得到分页索引的数组 ;k8U5=6a
ps.getTotalCount()得到总结果数 X@Yl<9|i
ps.getStartIndex()当前分页索引 lQ| i
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ps.getNextIndex()下一页索引 \<x{U3q5
ps.getPreviousIndex()上一页索引 {%QWv%|
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 T9]:,
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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 7jYW3
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一下代码重构了。 HfA@tZ5q|U
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我把原本我的做法也提供出来供大家讨论吧: zN>tSdNkI-
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首先,为了实现分页查询,我封装了一个Page类: Rs53R$PIR
java代码: +6\1
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/*Created on 2005-4-14*/ )Q c>NF0
package org.flyware.util.page; v Yw$m#@
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/** Kr74|W=
* @author Joa rB.LG'GG]
* W(jP??up
*/ ])mYE
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publicclass Page { e*pYlm
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/** imply if the page has previous page */ 7hl,dtn7
privateboolean hasPrePage; cfUG)-]P~
}+BbwBm&
/** imply if the page has next page */ RyZy2^0<
privateboolean hasNextPage; EALgBv>#ZL
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/** the number of every page */ )U:W
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privateint everyPage; kqp*o+Oz',
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/** the total page number */ 8% `Jf`
privateint totalPage; 3<ry/{#%
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/** the number of current page */
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privateint currentPage; +{@hD+
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/** the begin index of the records by the current #B8V2_M
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query */ rPF2IS(5
privateint beginIndex; zn/b\X/
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/** The default constructor */ b[ .pD3
public Page(){ zM++Z*
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} mE3M$2}
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/** construct the page by everyPage QHbjZJ
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* @param everyPage AOR(1Qyo
* */ p$zj2W+sN
public Page(int everyPage){ p^9u8T4l1
this.everyPage = everyPage; o 9{~F`{p
} hT[w" &3
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/** The whole constructor */ D|X@aUp8}
public Page(boolean hasPrePage, boolean hasNextPage, /|aD,JVN"
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int everyPage, int totalPage, GB`
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int currentPage, int beginIndex){ k)B]|,g7G0
this.hasPrePage = hasPrePage; yZqX[U
this.hasNextPage = hasNextPage; |-.r9;-b
this.everyPage = everyPage; E:S (v
this.totalPage = totalPage; kc}&\y
this.currentPage = currentPage; g;t>jgX
this.beginIndex = beginIndex; G|.5.FK^
} Yp8GW1@
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/** aW7)}"j4
* @return ew\ZF qA;
* Returns the beginIndex. Q*l_QnfG
*/ +!)v=NY
publicint getBeginIndex(){ GN@(!V#/4
return beginIndex; K*fh`Kz
} +N>&b%
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/** @/0-`Y@?
* @param beginIndex ^{w]r5d
* The beginIndex to set. o%$'-N
*/ Bd-@@d.H<
publicvoid setBeginIndex(int beginIndex){ LSW1,}/B
this.beginIndex = beginIndex; +6+!M_0wA
} 2JS&zF
ucgp=bye
/** j3)fmlA
* @return UsBtk
* Returns the currentPage. j5]6CG_
*/ l[Rl:k!
publicint getCurrentPage(){
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return currentPage; Qlgii_?#@
} =RH7 j
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/** oJbMUEQQq
* @param currentPage w8>
* The currentPage to set. t&L+]I'P3
*/ )H`1CcT
publicvoid setCurrentPage(int currentPage){ 6[l{@*r"
this.currentPage = currentPage; ELqpIXq#
} `dK%I
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/** 6;vfl*
* @return 1*ui|fuK
* Returns the everyPage. <zh N7="
*/ C
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publicint getEveryPage(){ Mo_(WSs
return everyPage; @O Rk
} euc|G Xs
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/** yp.\KLq8)
* @param everyPage UA]U_P$c
* The everyPage to set. Jx_BjkF
*/ yJGM"$
publicvoid setEveryPage(int everyPage){ |ZuS"'3_w
this.everyPage = everyPage; 1T@#gE["Ic
} o2#_CdU
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/** ^ ;XJG9a0\
* @return ?7"6dp_K
* Returns the hasNextPage. 7"0l>0 \
*/ k x26nDT(
publicboolean getHasNextPage(){ Y}Gf%Xi,
return hasNextPage; YdNmnB%J
} | Xv]s61
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/** )S2GPn7
* @param hasNextPage 7U_OUUg
* The hasNextPage to set. |SfmQ;
*/ 9et%Hn.K'
publicvoid setHasNextPage(boolean hasNextPage){ N5\]VCX
this.hasNextPage = hasNextPage; @XRN#_{
} 7C"&f *lEi
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/** n~|sMpd,M1
* @return &q0s8'qA
* Returns the hasPrePage. a-<&(jV
*/ /6PL
publicboolean getHasPrePage(){ #)hJ.0~3
return hasPrePage; Bp>Z?"hTe
} (viGL|Ogn
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/** ^a+H`RD
* @param hasPrePage sj& j\<(
* The hasPrePage to set. C`LHFqv
*/ lZ![?t}2`
publicvoid setHasPrePage(boolean hasPrePage){ q"O4}4`
this.hasPrePage = hasPrePage; zEYT,l
} mxQPOu
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/** r[}5<S Q
* @return Returns the totalPage. ,8^QV3
* /$NZj"#
*/ o+j~~P
publicint getTotalPage(){ <+\
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return totalPage; M!j: 2dT"
} B(TE?[ #
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/** oYn|>`+6:y
* @param totalPage CV
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* The totalPage to set. VA^yv1We
*/ \sZT[42
publicvoid setTotalPage(int totalPage){ +M^+qt;]V
this.totalPage = totalPage; 3+>;$
} +J<igb!S
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} v62M8r,Y
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ap y#8]
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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 WY)*3?
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个PageUtil,负责对Page对象进行构造: 6<
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java代码: y/(60H,{{
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/*Created on 2005-4-14*/ 7j22KQ|EX^
package org.flyware.util.page; |k ]{WCD]
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import org.apache.commons.logging.Log; w#Di
import org.apache.commons.logging.LogFactory; `BOG e;pl
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/** 8,^2'dK34
* @author Joa MaS"V`NI
* Q]v><
*/ n |e=7?H8
publicclass PageUtil { +8#hi5e
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privatestaticfinal Log logger = LogFactory.getLog aHR&6zj4
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(PageUtil.class); (+w>hCI
h.%)RW?
/** $9%UAqk9
* Use the origin page to create a new page @cC@(M~Ru
* @param page 9H6%\#rw
* @param totalRecords fDU_eyt/Z'
* @return A`nw(f_/
*/ {I:nza
publicstatic Page createPage(Page page, int "1iLfQ
zZ*\v
totalRecords){ 2iV/?.<Z&
return createPage(page.getEveryPage(), b\9MM
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page.getCurrentPage(), totalRecords); }F<=
} )@,zG(t5;
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/** /nas~{B
* the basic page utils not including exception 4/J"}S
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handler ?[z@R4at
* @param everyPage T5gL
* @param currentPage 7~2c"WE
* @param totalRecords D%%@+3a
* @return page JMVh\($,x
*/ 4;D>s8dgG
publicstatic Page createPage(int everyPage, int E$1P H)
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currentPage, int totalRecords){ T}r}uw`
everyPage = getEveryPage(everyPage); =`W#R
currentPage = getCurrentPage(currentPage); 7~
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int beginIndex = getBeginIndex(everyPage, :|PI_
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currentPage); *:tfz*FG$G
int totalPage = getTotalPage(everyPage, V|`w/P9g4
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totalRecords); eX3|<Bf
boolean hasNextPage = hasNextPage(currentPage, 3@8Zy:[8<
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totalPage); oa
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boolean hasPrePage = hasPrePage(currentPage); d:{#Dk#
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returnnew Page(hasPrePage, hasNextPage, z5q(
everyPage, totalPage, >Nr~7s
currentPage, 1P6!E*z\
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beginIndex); e4<[|B!O
} o)r%4YOL
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privatestaticint getEveryPage(int everyPage){ qtYVX:M@,
return everyPage == 0 ? 10 : everyPage; h'|J$
} =OR"Bd:O
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privatestaticint getCurrentPage(int currentPage){ >m'n#=yap
return currentPage == 0 ? 1 : currentPage; DNmP> ~
} (*Fb/
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privatestaticint getBeginIndex(int everyPage, int MNWuw;:v
4khc*fh
currentPage){ C
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return(currentPage - 1) * everyPage; V:*6R/Ft
} C]GW u~QF
R
Y ";SfYb
privatestaticint getTotalPage(int everyPage, int rcU*6`IWA
''3b[<
totalRecords){ dk[MT'DV
int totalPage = 0; aYrbB#
6)j/"9oY
if(totalRecords % everyPage == 0) dSPye z
totalPage = totalRecords / everyPage; ;tG@ 6
else lSK<LytB
totalPage = totalRecords / everyPage + 1 ; r$<4_*
e{E8_2d
return totalPage; ("txj[v-/
} -]!zj#&
:/~TV
privatestaticboolean hasPrePage(int currentPage){ >^TcO
return currentPage == 1 ? false : true; {}DoRpq=
} :{'%I#k2
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privatestaticboolean hasNextPage(int currentPage, Qoom[@$
6u[
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int totalPage){ . g8db d
return currentPage == totalPage || totalPage == r";;Fk#5
y|2y!&o,!
0 ? false : true; MCO`\"`l
} ~Sc{\ZJl
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} zn2Qp
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Z>(K|3_
j7sRmQCl
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。 UtYwG#/w
U C..)9
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 7 DW_G
TS49{^d$
做法如下: :`<ME/"YE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 o3,}X@p
\SyG#.$
的信息,和一个结果集List: -APbN(Vi
java代码: :O/QgGZN$
R}T\<6Y
s]'EIw}mo
/*Created on 2005-6-13*/ {2T;^+KE
package com.adt.bo; qj:\)#I
A40Q~X
import java.util.List; R>y/Y<5=
H*E4+3y
import org.flyware.util.page.Page; ..;ep2jSs
s_4y^w]aX
/** "pTU&He
* @author Joa ),5|Ves;t[
*/ _0h)O
publicclass Result { L.Tu7+M4
c$b~?Mx
private Page page; %[WOQ.Sh
Y0xn}:%K
private List content; SI9PgC
]CGH )4Pe
/** 49-wFF
* The default constructor N-YCOSUu
*/ ='Fh^]*5
public Result(){ "a=dx|
Z
super(); 6S&OE k
} DW>|'w %
=cWg39$(I
/** xV>sc;PEb
* The constructor using fields {pz7ADK<
* J?_-Dg(=
* @param page mIah[~G
* @param content /4{IxQk
*/ vu|-}v?:
public Result(Page page, List content){ -h%1rw
this.page = page; 4gh`
>
this.content = content; x9 i^_3Z
} TxvvCV^
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/** $5N\sdyZxg
* @return Returns the content. s}g3*_"
*/ tf4clzSTa
publicList getContent(){ ]:}x 4O#
return content; 6oy[0hj
} *yqke<o9)
Wo7`gf_ (
/** 5Mz6/&`
* @return Returns the page. vEC#W43l
*/ .Zm de*b
public Page getPage(){ *^i"q\n5(
return page; u]MQ(@HHF
} fir#5,*q|
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/** (o518fmR
* @param content +6Ye'IOG
* The content to set. 9" cyZO
*/ 35n'sVn
public void setContent(List content){ 9O|k|FD
this.content = content; yII+#?D
} (7w95xI
nQ08(8
/** N4$ K{
* @param page Ls/*&u
* The page to set. |u_fVQj
*/ d5#z\E??
publicvoid setPage(Page page){ &x)n K
this.page = page; >9,:i)m_
} K8{ef
} ui<Mnm_T;d
y1#*c$ O
sGO+O$J
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2. 编写业务逻辑接口,并实现它(UserManager, =k##*%
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UserManagerImpl) !dOpLUh l
java代码: C=x70Y/
k|3hs('y|
cQrXrij;!
/*Created on 2005-7-15*/ 349BQ5ND
package com.adt.service; 9yWSlbPr]
Kj/Lcx;bh
import net.sf.hibernate.HibernateException; x\aCZ
V<Co!2S
import org.flyware.util.page.Page; hQwUwfoe@
(je`sV
import com.adt.bo.Result; TFDzTD
jKb4d9aX
/** N14Q4v-*x
* @author Joa FB2{qG3
*/ Wn&9R
j
publicinterface UserManager { =kjD ]+l
3u/ GrsF
public Result listUser(Page page)throws N*SUA4bnuM
@`XbM7D 5
HibernateException; EAV6qW\r5]
h(p cGE
} O:Wd
,3_
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:+!4h
&Xh=bM'/%m
uTNy{RBD+
java代码: uoTc c|Kc
KN'twPFq
\0.!al0
/*Created on 2005-7-15*/ 't+'rG6x
package com.adt.service.impl; =Y*zF>#lP
=\)76xC20
import java.util.List; \?[ m%$A
i4lB]k
import net.sf.hibernate.HibernateException; &n]]OPo
<.:mp1,8V
import org.flyware.util.page.Page; <vd}oiB@
import org.flyware.util.page.PageUtil; 85BB{T;
}c=YiH,o
import com.adt.bo.Result; EpK7VW
import com.adt.dao.UserDAO; ]0=THq\H
import com.adt.exception.ObjectNotFoundException; sNZOm $
import com.adt.service.UserManager; J|CCTXT
3{M0iNc1
/** .p%V]Ka
* @author Joa O)c3Lm-w
*/ o.wXaS8
publicclass UserManagerImpl implements UserManager { WF-^pfRq~
I].ddR%
private UserDAO userDAO; 7>f)pfLM
~^>g<YR[
/** (dP9`Na]
* @param userDAO The userDAO to set. K0\`0E^,
*/ kH?PEA! \
publicvoid setUserDAO(UserDAO userDAO){ Ymm*p,`
this.userDAO = userDAO; _ygdv\^Tet
} !'Ww%ZL\
.J?RaH{i
/* (non-Javadoc) ik5"9b-\<
* @see com.adt.service.UserManager#listUser I5E+=.T*ar
x\pygzQ/
(org.flyware.util.page.Page) :=\`P
*/ d?><+!a
public Result listUser(Page page)throws |nY+Nen7
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HibernateException, ObjectNotFoundException { e}ivvs2
int totalRecords = userDAO.getUserCount(); $]MOAj"LH
if(totalRecords == 0) U04)XfO;]
throw new ObjectNotFoundException !,{-q)'D
-BH T'zq1S
("userNotExist"); KN~Rep cz@
page = PageUtil.createPage(page, totalRecords); uFL!*#A
List users = userDAO.getUserByPage(page); @%!Gj{
returnnew Result(page, users); Y#FSU#a$<
} z8
K#G%,:
y1#QP3'Z1
} 2[Xe:)d
06I(01M1
%>t4ib_8
*_"lXcG.
orhzeOi\
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 i}@5<&J
=Ds&ArG
询,接下来编写UserDAO的代码: ~zDFL15w
3. UserDAO 和 UserDAOImpl: JC9OL.Ob
java代码: [Vj|fy4
SDO~g ~NTp
+'aG{/J
/*Created on 2005-7-15*/ :|Bzbn=N2
package com.adt.dao; t![972.&
1pT/`x
import java.util.List; 5;A=8bryU
^9XAWj"
import org.flyware.util.page.Page; 2ZKy7p0/
:-~x~ah-
import net.sf.hibernate.HibernateException; KJ_L>$
]*
|UN#utw{^Y
/** A/.z. K
* @author Joa >Sm#-4B-
*/ *2Q x69`
publicinterface UserDAO extends BaseDAO { *-gmWATC6
jR{t=da
publicList getUserByName(String name)throws wV'_{/WM
29NP!W
/g
HibernateException; Hr/J6kyB)
Z$S0X$q}
publicint getUserCount()throws HibernateException; B|S X?X
Yy_mX}\x
publicList getUserByPage(Page page)throws :s|xa u=
6+Y@dJnPT
HibernateException; Ps~)l#gue
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} $B`bsJ
W |+&K0M
SpZmwa #\
g$mqAz<
%Gm4,+8P3o
java代码: WiFZY*iu5
h|ja67VG
@@|H8mP}H
/*Created on 2005-7-15*/ 3Ael
package com.adt.dao.impl; %j ?7O00@
hYh~[Kr^@^
import java.util.List; 6H:EBj54?
{=_xze)
import org.flyware.util.page.Page; Y4*?QBYA
*'R2Lo<C
import net.sf.hibernate.HibernateException; I#|ib
import net.sf.hibernate.Query; OgkbN`
(Jk:Qz5
import com.adt.dao.UserDAO; 1 w9Aoc
i(kr#XsU
/** 42 Sk`
* @author Joa LdyE*u_
*/ &XSe&1
public class UserDAOImpl extends BaseDAOHibernateImpl c1StA
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implements UserDAO { T4}q%%7l
%`:+A?zL
/* (non-Javadoc) KQ.cd]6
* @see com.adt.dao.UserDAO#getUserByName IFWP&20
U6 H@l#
(java.lang.String) O9F#gO|!
*/ Y+"Gx;F>
publicList getUserByName(String name)throws JDB Ni+t
}fz;La:b
HibernateException { *1_A$14l
String querySentence = "FROM user in class XPcx"zv\
5<?/M<i
com.adt.po.User WHERE user.name=:name"; ]BBjFs4#
Query query = getSession().createQuery ]yA_N>k2K
^Xslj
(querySentence); SMh[7lU`
query.setParameter("name", name); }Yp]A
return query.list(); =JB1 ]b{|
} YCNpJGM
jI807g+
/* (non-Javadoc) }ABHGr5[
* @see com.adt.dao.UserDAO#getUserCount() q.PXO3T
*/ ~kPZh1n`
publicint getUserCount()throws HibernateException { U+g<lgH1J
int count = 0; D~ %h3HM
String querySentence = "SELECT count(*) FROM 6-uB[$ko
PWs=0.Wj
user in class com.adt.po.User"; sxQMfbN
Query query = getSession().createQuery S31+ j:"
G-sA)WOF
(querySentence); 84maX'
count = ((Integer)query.iterate().next k'+Mc%pg4E
]}dAm S/
()).intValue(); !:Clzlg
return count; Q
GDfX_
} kM/;R)3t4/
;923^*\:F{
/* (non-Javadoc) Mhze!!
* @see com.adt.dao.UserDAO#getUserByPage b
`.h+=3
JV9Ft,xk
(org.flyware.util.page.Page) X.!|#FWb+
*/ !Ql&Ls
publicList getUserByPage(Page page)throws z c,Q
lDhuL;9e
HibernateException { /h73'"SpDy
String querySentence = "FROM user in class Iw) 'Yyg
qluaop
com.adt.po.User"; HCKj8-*
Query query = getSession().createQuery k/V:QdD Sb
5R7DD 5c[
(querySentence); _ ?Z :m
query.setFirstResult(page.getBeginIndex()) C8.MoFfhe
.setMaxResults(page.getEveryPage()); =qVD"Z]z
return query.list(); ?]u=5gqUU
} {H%1sI
;]Bkw6o
} ~b.e9FhdA
S4BU !
w@ =U f7
Og~3eL[1%C
au 5qbP
至此,一个完整的分页程序完成。前台的只需要调用 ;p 'Ej'E
%{M&"M v
userManager.listUser(page)即可得到一个Page对象和结果集对象 :0RfA%
yjxv D
的综合体,而传入的参数page对象则可以由前台传入,如果用 96
!e:TU
q%A.)1<'_
webwork,甚至可以直接在配置文件中指定。 lGtTZcg
4Fpu68y
下面给出一个webwork调用示例: Vtr5<:eEx
java代码:
S^4T#/
p/!P kKJ
"kT?9&