Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .wYx_
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 t5[{ihv~:
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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 9KD2C>d<
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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 -`#L rO;n
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分页支持类: G8eAj%88
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java代码: yQ6{-:`)
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package com.javaeye.common.util; /.Gx
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import java.util.List; q'{E $V)E
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publicclass PaginationSupport { $wC]S4C
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publicfinalstaticint PAGESIZE = 30; .(nq"&u-*
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privateint pageSize = PAGESIZE; e)>Z&e,3
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privateList items; 8V^gOUF.
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privateint totalCount; k45xtKS>d
= DvnfT<
privateint[] indexes = newint[0]; qDNqd
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privateint startIndex = 0; ,8EeSnI
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public PaginationSupport(List items, int 1rT}mm/e;
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totalCount){ n%@xnB$ZX
setPageSize(PAGESIZE); )T
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setTotalCount(totalCount); d v"
setItems(items); |L<oKMZY
setStartIndex(0); \S1WF?<,
} ogDyrY}]
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public PaginationSupport(List items, int xOPSw|!w
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totalCount, int startIndex){ y}nM'$p
setPageSize(PAGESIZE); S\s1}`pNm
setTotalCount(totalCount); ]p@7[8}
setItems(items); o+q4Vg9&
setStartIndex(startIndex);
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} %GjF;dJ
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public PaginationSupport(List items, int `N
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p*n$iroy_{
totalCount, int pageSize, int startIndex){ V'\4sPt
setPageSize(pageSize); a'XCT@B
setTotalCount(totalCount); P[aB}<1f0
setItems(items); Vad(PS0
setStartIndex(startIndex); ~Og'IRf
} IiS1ubNtZ
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publicList getItems(){ @ U:WWTzf
return items; Q/-YLf.
} o#Rao#bD:
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publicvoid setItems(List items){ F2OU[Z,-]
this.items = items; *cq#>rN
} 'xvV;bi
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publicint getPageSize(){ 1m|1eAGS{
return pageSize; PBR+NHrZ
} H Viu7kue`
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publicvoid setPageSize(int pageSize){ QWxCNt:^?
this.pageSize = pageSize; cSoZq4
} k;l^wM
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publicint getTotalCount(){ Y=/HsG\W]
return totalCount; !\RR UH*
} ^4c2}>f
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publicvoid setTotalCount(int totalCount){ >0T0K`o
if(totalCount > 0){ }0}J
this.totalCount = totalCount; : :e=6i
int count = totalCount / V]`V3cy1+3
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pageSize; 82efqzT
if(totalCount % pageSize > 0) W^P%k:anK
count++; .@ /5Ln
indexes = newint[count]; ?(;ygjyx
for(int i = 0; i < count; i++){ 6D/5vM1
indexes = pageSize * %t:1)]2
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i; w~&bpCB!
} Kx ?}%@b
}else{ x!]ZVl]
this.totalCount = 0; hRtnO|Z6
} $BkdC'D
} ,dK% [
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publicint[] getIndexes(){ eNi.d;8F
return indexes; VCkhK9(N
} jFbz:aUF
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publicvoid setIndexes(int[] indexes){ @_h/%>0
this.indexes = indexes; u.1u/o1"
} 5-5qm[.;
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publicint getStartIndex(){ U_Emp[
return startIndex; RR*z3i`PP
} UIIunA9
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publicvoid setStartIndex(int startIndex){ dD@T}^j *|
if(totalCount <= 0) sW@4r/F>:D
this.startIndex = 0; UOT~L4G
elseif(startIndex >= totalCount) +twJHf_U
this.startIndex = indexes e8--qV#<
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[indexes.length - 1]; J$]d%p_I
elseif(startIndex < 0) kG@1jMPtQ
this.startIndex = 0; FwmE1,
else{ on\0i{0l8
this.startIndex = indexes >eW HPO
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[startIndex / pageSize]; PHT;%;m=
} w!8h4U.
;
} \7jcZ~FBX%
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publicint getNextIndex(){ y85GKysT
int nextIndex = getStartIndex() + &*T57tE
"((6)U#
pageSize; htkn#s~=
if(nextIndex >= totalCount) s:i$ s")
return getStartIndex(); (B7M*e
else /J wQ5
return nextIndex; }V6}>!Sb
} 9iUkvnphh
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publicint getPreviousIndex(){ 6 @'v6 1'
int previousIndex = getStartIndex() - vAHJP$x
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;,
pageSize; Go+f0aig
if(previousIndex < 0) enDjP
return0; i[T!{<
else q71Tg
return previousIndex; ;,'eO i
} N r
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} +wS?Z5%mU
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抽象业务类 CP["N(fF
java代码: mWfzL'*
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/** eiJ $}\qJL
* Created on 2005-7-12 !xA;(<K[^
*/ @]gP"Pp
package com.javaeye.common.business; ZMy,<wk
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import java.io.Serializable; }+,1G!?z
import java.util.List; )LKutN?tBy
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import org.hibernate.Criteria; s-3vp
import org.hibernate.HibernateException; ,K,n{3]
import org.hibernate.Session; !1-:1Whz8
import org.hibernate.criterion.DetachedCriteria; QE m6#y
import org.hibernate.criterion.Projections; Z_ak4C
import #e{l:!uS\
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org.springframework.orm.hibernate3.HibernateCallback; o3qBRT0[R
import M,3sK!`>
}9:d(B9;
org.springframework.orm.hibernate3.support.HibernateDaoS |r%6;8A]i
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upport; u\Tq5PYXt
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import com.javaeye.common.util.PaginationSupport; '\[GquK;P
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public abstract class AbstractManager extends :>\ i
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HibernateDaoSupport { @'7'3+ c
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privateboolean cacheQueries = false; CRw.UC\
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privateString queryCacheRegion;
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publicvoid setCacheQueries(boolean Fnzv&
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cacheQueries){ tF
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this.cacheQueries = cacheQueries; k-*H=km
} L|u\3.:
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publicvoid setQueryCacheRegion(String ;SagN
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queryCacheRegion){ Nw/4z$].J
this.queryCacheRegion = =NQDxt}
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queryCacheRegion; g-bHf]'
} wC}anq>>
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publicvoid save(finalObject entity){ J)"2^?!&B
getHibernateTemplate().save(entity); /hQTV!\u
} 0h_ 9
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publicvoid persist(finalObject entity){ L(fOe3
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getHibernateTemplate().save(entity); g\,pZ]0i
} [?Cv^t${+
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publicvoid update(finalObject entity){ H"=%|/1M0
getHibernateTemplate().update(entity); kD8$ir'UYG
} ^yb3L1y
.!/DM-C
publicvoid delete(finalObject entity){ X6)-1.T&
getHibernateTemplate().delete(entity); ;%0$3a
} &z+nNkr?yN
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publicObject load(finalClass entity, |Rd?s0u
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finalSerializable id){ SDwTGQ/0
return getHibernateTemplate().load ^KM' O8
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(entity, id); &CpxD."8x
} G%jgr"]\z
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publicObject get(finalClass entity, !KKkw4
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finalSerializable id){ V|gW%Z,j
return getHibernateTemplate().get >B!E 6ah
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(entity, id); m9 o{y6_j*
} %JF^@\E!|
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publicList findAll(finalClass entity){ `*g(_EZsS
return getHibernateTemplate().find("from ,&e0~
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" + entity.getName()); ($pN OGH
} MKf|(6;~
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publicList findByNamedQuery(finalString _kg<KD=P
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namedQuery){ @a$_F3W
return getHibernateTemplate LmWZ43Z"@
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().findByNamedQuery(namedQuery); BZ*',\o
} j)xRzImu
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publicList findByNamedQuery(finalString query, Y3=5J\d!a
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finalObject parameter){ Iv+JEuIi
return getHibernateTemplate ,h,OUo]LIY
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().findByNamedQuery(query, parameter); c!*yxzs\
}
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publicList findByNamedQuery(finalString query, Ne#FBRu5
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finalObject[] parameters){ `@TWZ%f6
return getHibernateTemplate d9e_slx
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().findByNamedQuery(query, parameters); v3O+ ;4
} 7^)8DwAl
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publicList find(finalString query){ 0)F.Y,L
return getHibernateTemplate().find '5V}Z3zJ/
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(query); .j^tFvN~L
} iZY4+
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publicList find(finalString query, finalObject M$_E:u&D
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parameter){ ~wYGTm=(n
return getHibernateTemplate().find x3DUz
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(query, parameter); 3r^Ls[ey
} S!WG|75B
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public PaginationSupport findPageByCriteria 2iM]t&^<+
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(final DetachedCriteria detachedCriteria){ =r|e]4
return findPageByCriteria idsBw!DB
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); J([Y4Em5
} Y*VF1M,2_
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public PaginationSupport findPageByCriteria )R6h
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(final DetachedCriteria detachedCriteria, finalint +FomAs1*f
)qSjI_qt5
startIndex){ ]31>0yj[Q
return findPageByCriteria %#t*3[
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(detachedCriteria, PaginationSupport.PAGESIZE, I]GGmN
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startIndex); u00w'=pe)
} 5 EhOvt8
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public PaginationSupport findPageByCriteria TOT#l6yqdd
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(final DetachedCriteria detachedCriteria, finalint O06 2c)vIY
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pageSize, ,3XlX(P
finalint startIndex){ 6v"WI@b4
return(PaginationSupport) '/="bSF
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getHibernateTemplate().execute(new HibernateCallback(){ A@uU*]TqJ8
publicObject doInHibernate f/7on|bv
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(Session session)throws HibernateException { qu\cU(H|
Criteria criteria = ,V^2Oa
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detachedCriteria.getExecutableCriteria(session); =kzuU1s
int totalCount = lA{JpH_Y8s
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((Integer) criteria.setProjection(Projections.rowCount -kF8ZF
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()).uniqueResult()).intValue(); o$QC:%[#
criteria.setProjection A"tE~m;"7
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(null); 6Y`rQ/F
List items = 7Pe<0K)s(
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criteria.setFirstResult(startIndex).setMaxResults
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(pageSize).list(); r01u3!
PaginationSupport ps = *iX PG9XZ
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new PaginationSupport(items, totalCount, pageSize, >sjvE4s
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startIndex); n'To:
return ps; "D,}|
} &=*sN`
}, true); R$h
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} %i6/=
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public List findAllByCriteria(final l{I.l
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DetachedCriteria detachedCriteria){ IM$ d~C
return(List) getHibernateTemplate Wr3z%1
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().execute(new HibernateCallback(){ =;"e Z
publicObject doInHibernate W7W(jMH
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(Session session)throws HibernateException { 5BJn_<
Criteria criteria = H Y~[/H+:
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detachedCriteria.getExecutableCriteria(session); iNs@8<=$T
return criteria.list(); cG"wj$'w
} *(s0X[-
}, true); Cxd^i
} h,\5C/
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public int getCountByCriteria(final KV 8Ok
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DetachedCriteria detachedCriteria){ %I=/
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Integer count = (Integer) u4tv=+jh
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getHibernateTemplate().execute(new HibernateCallback(){ {%_D>y
publicObject doInHibernate W|Cs{rBc?
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(Session session)throws HibernateException { ov<vSc<u
Criteria criteria = O7]kcA
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detachedCriteria.getExecutableCriteria(session); T[evh]koB
return H|S hi /
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criteria.setProjection(Projections.rowCount 3*T/ 7\
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()).uniqueResult(); g"~`\xhx
} EQe$~}[
}, true); SdF+b+P]
return count.intValue(); J%]5C}v \
} 1#3eY?Nb
} K]1|#`n
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用户在web层构造查询条件detachedCriteria,和可选的 U;A,W$<9
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Kum" }ux
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PaginationSupport的实例ps。 *k,{[b
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ps.getItems()得到已分页好的结果集 ykRd+H-t
ps.getIndexes()得到分页索引的数组 HzL~B#
ps.getTotalCount()得到总结果数 %ikPz~(
ps.getStartIndex()当前分页索引 ~|[i64V<^
ps.getNextIndex()下一页索引 ![!,i\x
ps.getPreviousIndex()上一页索引 nq,:UYNJ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 EL%P v1
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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 6B]i}nFH{+
f,kV
一下代码重构了。 )gz]F_
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我把原本我的做法也提供出来供大家讨论吧: aeVd.`lxM
1Q=L/keP
首先,为了实现分页查询,我封装了一个Page类: /oZvm
java代码: 9@?|rje9
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/*Created on 2005-4-14*/ V*r/0|vd
package org.flyware.util.page; }+}Cl T
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/** Z<W f/
* @author Joa ;s #I b_
* i1X!G|Awfv
*/ P'[ISGt
publicclass Page { fu{v(^
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/** imply if the page has previous page */ S?zP;
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privateboolean hasPrePage; [0 rH/{
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/** imply if the page has next page */ #S]O|$&*
privateboolean hasNextPage; *%\Xw*\0
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/** the number of every page */ x?]fHin_
privateint everyPage; ul
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/** the total page number */ @=}NMoNH
privateint totalPage; w#_7,*6]
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/** the number of current page */ ;dtA-EfOZ
privateint currentPage; fLeHn,*,"
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/** the begin index of the records by the current mKE'l'9A_
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query */ EiP N44(
privateint beginIndex; ]T(qk
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/** The default constructor */ vXZP>
public Page(){ ?%%vQ?
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} ]k BC,m(
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/** construct the page by everyPage N"0>)tG
* @param everyPage gK"(;Jih$
* */ G^z>2P
public Page(int everyPage){ ,Y#f0
this.everyPage = everyPage; <Fv7JPN%
} cp"{W-Q{$
*3h_'3yo@
/** The whole constructor */ VZe'6?#
public Page(boolean hasPrePage, boolean hasNextPage, DZ $O%
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int everyPage, int totalPage, asE.!g?
int currentPage, int beginIndex){
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this.hasPrePage = hasPrePage; fh66Gn,
this.hasNextPage = hasNextPage; 4#t=%}
this.everyPage = everyPage; WRRR "Q$
this.totalPage = totalPage; !b+!] 2~g}
this.currentPage = currentPage; P(o>UDy
this.beginIndex = beginIndex; T!pA$eE
} :o87<)
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/** !HtW~8|:
* @return oA:`=f%\
* Returns the beginIndex. .
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*/ ]dV$H
publicint getBeginIndex(){ ++ 5!8Nv
return beginIndex; a<]vHC7
} >]A#_p
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/** n
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* @param beginIndex hQz1zG`z7
* The beginIndex to set. ~0o>B$xJ
*/ sO!m,pK(
publicvoid setBeginIndex(int beginIndex){ |9BX
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this.beginIndex = beginIndex; c>T)Rc
} 7VdxQ T
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/** F7/%,vf
* @return uJ fXe
* Returns the currentPage. ]l3Y=Cl
*/ T-iQ!D~
publicint getCurrentPage(){ V}~',o<m
return currentPage; |N3#of(
} %sPq*w.
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/** %Na`\`L{F
* @param currentPage cBU3Q<^
* The currentPage to set. hBifn\dFr
*/ ah(k!0PV
publicvoid setCurrentPage(int currentPage){ dDAl n+
this.currentPage = currentPage; DeeV;?:
} epG =)gd=8
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/** +D[C.is>]}
* @return 5`lVC$cP
* Returns the everyPage. 0zsmZ]b5E
*/ O%aHQL%Sz
publicint getEveryPage(){ obv_?i1
return everyPage; (yeWArQ
} ]US!3R^
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/** +tG'
* @param everyPage \.GA"_y
* The everyPage to set. SL\15`[{
*/ fP8bWZ{
publicvoid setEveryPage(int everyPage){ C*11?B[
this.everyPage = everyPage; '$z@40u
} SLH;iqPT
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/** ^>eV}I5ak
* @return u6:$AA
* Returns the hasNextPage. <K>qK]|C
*/ m,6[;
publicboolean getHasNextPage(){ fEtBodA)
return hasNextPage; T{N8 K K
} o{l]n*
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/** 9[
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* @param hasNextPage EN,}[^Z
* The hasNextPage to set. 'z=d&K
*/ 6(Ntt
publicvoid setHasNextPage(boolean hasNextPage){ nQg_1+
this.hasNextPage = hasNextPage; LY#V)f
} Q)8I(*
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/** 9C!b
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* @return <^942y-=
* Returns the hasPrePage. 9T1-{s
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*/ [o7Qr?RN
publicboolean getHasPrePage(){ =+[`9
return hasPrePage; F[)tg#}@G
} g&8-X?^Q
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/** q]s_ hWWv
* @param hasPrePage t\v~ A0
* The hasPrePage to set. *<h )q)HS
*/ ~~m(CJ4S
publicvoid setHasPrePage(boolean hasPrePage){ f|3LeOyz
this.hasPrePage = hasPrePage; ~0}d=d5g
} ^7t1'A8e<
*/|<5X;xIA
/** d7 :=axo,
* @return Returns the totalPage. 'TA
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* pTncx%!W5
*/ kjOkPp
publicint getTotalPage(){ lg{/5gQG
return totalPage; 1F+JyZK}w
} )@=fGN Dt
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/** ''q#zEf6
* @param totalPage P{: 5i%qC
* The totalPage to set. k%aJ%(
*/ SO<9?uk.
publicvoid setTotalPage(int totalPage){ hrXk 7}9
this.totalPage = totalPage; FMWM:
} .*J /F$
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} YlR9
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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 A!}Ps"Z
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个PageUtil,负责对Page对象进行构造: fP$rOJ)P
java代码: "g!ek3w(
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/*Created on 2005-4-14*/ 8==_43
package org.flyware.util.page; F6>oGmLy
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import org.apache.commons.logging.Log; .S4%Q9l
import org.apache.commons.logging.LogFactory; k-)Ls~#+
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/** }KEr@h,N
* @author Joa (Ap?ixrR_
* )#`&[9d-
*/ bU/YU0ZIT
publicclass PageUtil { 'T;;-M3*
h
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privatestaticfinal Log logger = LogFactory.getLog Ry? f; s
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(PageUtil.class); N:Ir63X*#
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/** k^zU;
* Use the origin page to create a new page .>LJ(Sx9b
* @param page Z'|k M!
* @param totalRecords dfZ`M^NU
* @return s .+`"rK
*/ Q\btl/?
publicstatic Page createPage(Page page, int Wr'1Y7z
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totalRecords){ ,R-aO= %
return createPage(page.getEveryPage(), P>03 DkbB
b #Llu$
page.getCurrentPage(), totalRecords); =hY/Yr%P
} 4U u`1gtz
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/** jX^_(Kg
* the basic page utils not including exception #Jr4LQ@A9
6&
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handler
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* @param everyPage v2="j
* @param currentPage 'E\4/0 !
* @param totalRecords su3Wk,MLP
* @return page xJA{Hws
*/ oArJ%Y>
publicstatic Page createPage(int everyPage, int `;j$]
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currentPage, int totalRecords){ ~qK/w0=j
everyPage = getEveryPage(everyPage); \)ZCB7|
currentPage = getCurrentPage(currentPage); }<*KM)%
int beginIndex = getBeginIndex(everyPage, G^eXJusOv
81w"*G5AM
currentPage); c%1{l]
int totalPage = getTotalPage(everyPage, ;WgUhA
;q
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totalRecords); _rmKvSD%
boolean hasNextPage = hasNextPage(currentPage, e^$JGh2
15r=d
totalPage); {w7/M]m-
boolean hasPrePage = hasPrePage(currentPage); ExeZj8U
E=`/}2
returnnew Page(hasPrePage, hasNextPage, c5:X$k\
everyPage, totalPage, Z[eWey_
currentPage, DgY
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|"+Ufw^
beginIndex); `3@?)xa
} l,zhBnD
h[Uo6`
privatestaticint getEveryPage(int everyPage){ <1
;pyw
y
return everyPage == 0 ? 10 : everyPage; e+MQmWA'F
} yrd1J$
vTTXeS-b
privatestaticint getCurrentPage(int currentPage){ T k@ ~w
return currentPage == 0 ? 1 : currentPage; U.JE \/
} i83[':
Q|e-)FS)
privatestaticint getBeginIndex(int everyPage, int
90K&oof?M
UM<s#t`\3
currentPage){ ^)(tO$S
return(currentPage - 1) * everyPage; m;t&P58f
} +'nMy"j1
)4m`Ya,E3
privatestaticint getTotalPage(int everyPage, int d`=LZio
<Y2$'ETD
totalRecords){ 4u"Bll
int totalPage = 0; D2=zrU3Y64
b};o:
if(totalRecords % everyPage == 0) Rd|8=`)
totalPage = totalRecords / everyPage; OHrzN']
else '$?!>HN4
totalPage = totalRecords / everyPage + 1 ; oR/_{#Mz"
\ Ce*5h
return totalPage; )ax>*
} /?($W|9+l
;mvVo-r*q
privatestaticboolean hasPrePage(int currentPage){ +.OdrvN4)
return currentPage == 1 ? false : true;
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} c*(^:#"9
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privatestaticboolean hasNextPage(int currentPage, m^=El7+
N/--6)5~0
int totalPage){ T[#q0bv
return currentPage == totalPage || totalPage == ?~!9\dek,
n?;rWq"
0 ? false : true; xu%eg]
} 1<5Ug8q
HIx%c5^
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} Vxu V`Plf
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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。 :2&"ak>N
ODhq
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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 xwi6#>
c+ByEP4EG
做法如下: x~wS/y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 -a &<Un/
4e#$-V
的信息,和一个结果集List: w6WPfy(/2
java代码: )%3T1
D/
j@D,2B;
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/*Created on 2005-6-13*/ XM,slQ
package com.adt.bo; qb/}&J7+
o. ;Vrc
import java.util.List; ^_<|~
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import org.flyware.util.page.Page; Y#tur`N
y&-QLX L
/** nosD1sS.K8
* @author Joa B4wRwrVI>
*/ [~ 2imS
publicclass Result { nw0#gDI|
/ of K7/
private Page page; 2J8:_Ql3I
u+KZ. n/
private List content; :dAd5v2f
q!?*M?Oz
/** a6^_iSk
* The default constructor "Y=`w,~~
*/ T'@+MA) ~
public Result(){ >m..
super(); oPM*VTMA
} 13`Mt1R
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/** Zd-6_,r
* The constructor using fields
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* y& 1@d+Lf
* @param page ?1a9k@[t
* @param content % hvK;B?Y|
*/ Jk6}hUH,
public Result(Page page, List content){ \m
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this.page = page; $2L6:&.P,
this.content = content; 6CIzT.
} -p.\fvip
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/** va'F '|
* @return Returns the content. e)g&q'O
*/ n=vDEX:'
publicList getContent(){ *{!Y_FrL
return content; hW<v5!,
} @qq"X'3t
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/** HOF$(86zqA
* @return Returns the page. X["xC3 i
*/ G+t:]\
public Page getPage(){ %dFJ'[jDL
return page; h%Nd89//
} ,7]hjf_h
q1( [mHZ
/** n]ba1t8ZA
* @param content '=n?^EPE3
* The content to set. 4^F%bXJ)
*/ N+rU|iMa.
public void setContent(List content){ t'l4$}(
this.content = content; MmR6V#@:
} ]f0'YLG
.Dr!\.hL
/** c{BAQZVc
* @param page wG3b{0
* The page to set. =abcLrf2G
*/ jk03 Hd
publicvoid setPage(Page page){ 7RL J
this.page = page; MQ-u9=ys
} {;c'@U
} :aej.>I0
-}|L<~
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E
d?2ORr|m=
2. 编写业务逻辑接口,并实现它(UserManager, Cp6S2v I
T8x)i\<
UserManagerImpl) Og/aTR<;=
java代码: $`E?=L`$
q[,p#uJ]
yu6{ 6[
/*Created on 2005-7-15*/ O -1O@:}c
package com.adt.service; J**(7d
~v.mbh
import net.sf.hibernate.HibernateException; vSH,fS-n
Q'/sP 5Pj
import org.flyware.util.page.Page; d+D~NA[M
oLT#'42+H
import com.adt.bo.Result; L7-BuW}&
1
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/** ew~Z/ A
* @author Joa >v.fH6P,}
*/ P1Hab2%+
publicinterface UserManager { wtY)(ka
sFTAE1|
public Result listUser(Page page)throws tQ|c.`)W
olE(#}7V
HibernateException; 7~e,"^>T
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} w\bwa!3Y
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d:(Ex^^
L,[Q/$S8
java代码: ny5P*yWEh
1;ttwF>G7
9|1msg4
/*Created on 2005-7-15*/ im2mA8OH
package com.adt.service.impl; eU1F7LS
ez,.-@O
import java.util.List; 9Da{|FyrD
gyw=1q+
import net.sf.hibernate.HibernateException; |LZ;2 i
Z-PBCU
import org.flyware.util.page.Page; '~D4%WKT
import org.flyware.util.page.PageUtil; Z7a@$n3h
>^s2$@J?p
import com.adt.bo.Result; _QL|pLf-
import com.adt.dao.UserDAO; u}@N
Qeg
import com.adt.exception.ObjectNotFoundException; ba|xf@=&
import com.adt.service.UserManager; K81X32Lm'
d`^3fr'.4A
/** J:@gmo`M;V
* @author Joa )D+BvJ Y"
*/ $ZM'dIk?
publicclass UserManagerImpl implements UserManager { #n>U7j9`O
.G{cx=;
private UserDAO userDAO; 3K
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/** z9aR/:W}
* @param userDAO The userDAO to set. |]?f6^|4
*/ F1#{(uW
publicvoid setUserDAO(UserDAO userDAO){ q`*.F#/4c
this.userDAO = userDAO; |[?Otv
} ieZ$@3#&z
u#76w74
/* (non-Javadoc) Y)sB]!hx
* @see com.adt.service.UserManager#listUser )p\`H;7*V4
jJ#D`iog5
(org.flyware.util.page.Page) >v+1v
*/ s2O()u-
public Result listUser(Page page)throws t1w5U+z
COh#/-`\1
HibernateException, ObjectNotFoundException { q\EYsN</;
int totalRecords = userDAO.getUserCount(); 8^UF0>`'
if(totalRecords == 0) jY=y<R_oK
throw new ObjectNotFoundException J&A1]T4d
Ib..X&N2
("userNotExist"); ZmsYRk~@-
page = PageUtil.createPage(page, totalRecords); 1Wpu
List users = userDAO.getUserByPage(page); vB7Gx>BQd
returnnew Result(page, users); Fv^zSoi2
} ZNBowZI
`UsJaoR#f
} ?Lg<)B9
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ojM'8z0Hn
32ki ?\P
vi##E0,N'^
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 tWIOy6`
:r
q~5hK
询,接下来编写UserDAO的代码: eFiG:LS7
3. UserDAO 和 UserDAOImpl: 5iA>Z!sP[
java代码: 50_[hC&C)
wH~A>
4*(
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cr
/*Created on 2005-7-15*/ cGV%=N^BE<
package com.adt.dao; KQfWpHwfj
xuXPVJdi
import java.util.List; <XLae'R
$g>bp<9v4
import org.flyware.util.page.Page; syX?O'xJ
DTezG':
import net.sf.hibernate.HibernateException; ~+\=X`y
H$I~Vz[\yb
/** r2RJb6
* @author Joa +f/
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*/ b}qfOgd5
publicinterface UserDAO extends BaseDAO { ~J].~^[
5M5Bm[X
publicList getUserByName(String name)throws |S8$NI2
eo]nkyYDP
HibernateException; A%D'Z85
-
!aT:0m$:9c
publicint getUserCount()throws HibernateException; "@G[:(BoB<
{)qr3-EM#
publicList getUserByPage(Page page)throws -}6ew@GE
IW\^-LI.
HibernateException; _[6sr7H!
@aS)=|Ls\
} 0F)v9EK(W4
sC3Vj(d!i
fu!T4{2
$ar^U
m,HE4`g
java代码: ai<qK3!O
9`f@"%h
$FPq8$V
/*Created on 2005-7-15*/ (.#nl}fA
package com.adt.dao.impl; X_78;T)uA
ys`-QlkB
import java.util.List; fG0ZVV!
tX^6R
import org.flyware.util.page.Page; ]aPf-O*
do8[wej<:
import net.sf.hibernate.HibernateException; ](JrEg$K
import net.sf.hibernate.Query; 6_`Bo%
f/Y&)#g>k
import com.adt.dao.UserDAO; [5&k{*}}
=`+D/
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/** yr%[IX]R
* @author Joa .)/."V
*/ eA&