org.teiid.query.sql.lang
Class From

java.lang.Object
  extended by org.teiid.query.sql.lang.From
All Implemented Interfaces:
java.lang.Cloneable, LanguageObject

public class From
extends java.lang.Object
implements LanguageObject

Represents a FROM clause in a SELECT query. The from clause holds a set of FROM subclauses. Each FROM subclause can be either a single group (UnaryFromClause) or a join predicate (JoinPredicate).


Nested Class Summary
 
Nested classes/interfaces inherited from interface org.teiid.query.sql.LanguageObject
LanguageObject.Util
 
Constructor Summary
From()
          Constructs a default instance of this class.
From(java.util.List parameters)
          Constructs an instance of this class from an ordered set of from clauses
 
Method Summary
 void acceptVisitor(LanguageVisitor visitor)
          Method for accepting a visitor.
 void addClause(FromClause clause)
          Add a clause to the FROM
 void addClauses(java.util.Collection clauses)
          Add clauses to the FROM
 void addGroup(GroupSymbol group)
          Adds a new group to the list (it will be wrapped in a UnaryFromClause)
 void addGroups(java.util.Collection<GroupSymbol> groups)
          Adds a new collection of groups to the list
 java.lang.Object clone()
          Return copy of this From clause.
 boolean containsGroup(GroupSymbol group)
          Checks if a group is in the From
 boolean equals(java.lang.Object obj)
          Compare two Froms for equality.
 java.util.List getClauses()
          Get all the clauses in FROM
 java.util.List<GroupSymbol> getGroups()
          Returns an ordered list of the groups in all sub-clauses.
 int hashCode()
          Get hashcode for From.
 void setClauses(java.util.List clauses)
          Set all the clauses
 java.lang.String toString()
          Returns a string representation of an instance of this class.
 
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

From

public From()
Constructs a default instance of this class.


From

public From(java.util.List parameters)
Constructs an instance of this class from an ordered set of from clauses

Parameters:
parameters - The ordered list of from clauses
Method Detail

addClause

public void addClause(FromClause clause)
Add a clause to the FROM

Parameters:
clause - Add a clause to the FROM

addClauses

public void addClauses(java.util.Collection clauses)
Add clauses to the FROM

Parameters:
clauses - Collection of FromClauses

getClauses

public java.util.List getClauses()
Get all the clauses in FROM

Returns:
List of FromClause

setClauses

public void setClauses(java.util.List clauses)
Set all the clauses

Parameters:
clauses - List of FromClause

addGroup

public void addGroup(GroupSymbol group)
Adds a new group to the list (it will be wrapped in a UnaryFromClause)

Parameters:
group - Group to add

addGroups

public void addGroups(java.util.Collection<GroupSymbol> groups)
Adds a new collection of groups to the list

Parameters:
groups - Collection of GroupSymbol

getGroups

public java.util.List<GroupSymbol> getGroups()
Returns an ordered list of the groups in all sub-clauses.

Returns:
List of GroupSymbol

containsGroup

public boolean containsGroup(GroupSymbol group)
Checks if a group is in the From

Parameters:
group - Group to check for
Returns:
True if the From contains the group

acceptVisitor

public void acceptVisitor(LanguageVisitor visitor)
Description copied from interface: LanguageObject
Method for accepting a visitor. It is the responsibility of the language object to call back on the visitor.

Specified by:
acceptVisitor in interface LanguageObject
Parameters:
visitor - Visitor being used

clone

public java.lang.Object clone()
Return copy of this From clause.

Specified by:
clone in interface LanguageObject
Overrides:
clone in class java.lang.Object
Returns:
Deep clone of this object

equals

public boolean equals(java.lang.Object obj)
Compare two Froms for equality. Order is not important in the from, so this is a set comparison.

Overrides:
equals in class java.lang.Object

hashCode

public int hashCode()
Get hashcode for From. WARNING: The hash code relies on the variables in the select, so changing the variables will change the hash code, causing a select to be lost in a hash structure. Do not hash a From if you plan to change it.

Overrides:
hashCode in class java.lang.Object

toString

public java.lang.String toString()
Returns a string representation of an instance of this class.

Overrides:
toString in class java.lang.Object
Returns:
String representation of object


Copyright © 2011. All Rights Reserved.