org.apache.calcite.sql

Class SqlCollation

java.lang.Object

org.apache.calcite.sql.SqlCollation

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

JavaCollation

public class SqlCollation
extends Object
implements Serializable

A SqlCollation is an object representing a Collate statement. It is immutable.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	SqlCollation.Coercibility A <character value expression> consisting of a column reference has the coercibility characteristic Implicit, with collating sequence as defined when the column was created.

Field Summary

Fields

Modifier and Type	Field and Description
static SqlCollation	COERCIBLE
protected String	collationName
static SqlCollation	IMPLICIT
protected Locale	locale
protected String	strength
protected SerializableCharset	wrappedCharset

Constructor Summary

Constructors

Constructor and Description
SqlCollation(SqlCollation.Coercibility coercibility) Creates a SqlCollation with the default collation name and the given coercibility.
SqlCollation(SqlCollation.Coercibility coercibility, Locale locale, Charset charset, String strength) Creates a Collation by its coercibility, locale, charset and strength.
SqlCollation(String collation, SqlCollation.Coercibility coercibility) Creates a Collation by its name and its coercibility.

Method Summary

Modifier and Type	Method and Description
boolean	equals(@Nullable Object o)
protected String	generateCollationName(Charset charset)
Charset	getCharset()
SqlCollation.Coercibility	getCoercibility()
protected static @Nullable SqlCollation	getCoercibilityDyadic(SqlCollation col1, SqlCollation col2) Returns the result for getCoercibilityDyadicComparison(org.apache.calcite.sql.SqlCollation, org.apache.calcite.sql.SqlCollation) and getCoercibilityDyadicOperator(org.apache.calcite.sql.SqlCollation, org.apache.calcite.sql.SqlCollation).
static String	getCoercibilityDyadicComparison(SqlCollation col1, SqlCollation col2) Returns the collating sequence (the collation name) to use for the resulting value of a comparison.
static @Nullable SqlCollation	getCoercibilityDyadicOperator(SqlCollation col1, SqlCollation col2) Returns the collating sequence (the collation name) and the coercibility for the resulting value of a dyadic operator.
static SqlCollation	getCoercibilityDyadicOperatorThrows(SqlCollation col1, SqlCollation col2) Returns the collating sequence (the collation name) and the coercibility for the resulting value of a dyadic operator.
String	getCollationName()
@Nullable Collator	getCollator() Returns the Collator to compare values having the current collation, or null if no specific Collator is needed, in which case String.compareTo(java.lang.String) will be used.
Locale	getLocale()
int	hashCode()
String	toString()
void	unparse(SqlWriter writer)

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

COERCIBLE

public static final SqlCollation COERCIBLE

IMPLICIT

public static final SqlCollation IMPLICIT

collationName

protected final String collationName

wrappedCharset

protected final SerializableCharset wrappedCharset

locale

protected final Locale locale

strength

protected final String strength

Constructor Detail

SqlCollation

public SqlCollation(SqlCollation.Coercibility coercibility)

Creates a SqlCollation with the default collation name and the given coercibility.

Parameters:

coercibility - Coercibility

SqlCollation

public SqlCollation(String collation,
                    SqlCollation.Coercibility coercibility)

Creates a Collation by its name and its coercibility.

Parameters:

collation - Collation specification

coercibility - Coercibility

SqlCollation

public SqlCollation(SqlCollation.Coercibility coercibility,
                    Locale locale,
                    Charset charset,
                    String strength)

Creates a Collation by its coercibility, locale, charset and strength.

Method Detail

equals

public boolean equals(@Nullable Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

generateCollationName

protected String generateCollationName(@UnderInitialization SqlCollation this,
                                       Charset charset)

getCoercibilityDyadicOperator

public static @Nullable SqlCollation getCoercibilityDyadicOperator(SqlCollation col1,
                                                                   SqlCollation col2)

Returns the collating sequence (the collation name) and the coercibility for the resulting value of a dyadic operator.

Parameters:

col1 - first operand for the dyadic operation

col2 - second operand for the dyadic operation

Returns:

the resulting collation sequence. The "no collating sequence" result is returned as null.

See Also:

SQL:1999 Part 2 Section 4.2.3 Table 2

getCoercibilityDyadicOperatorThrows

public static SqlCollation getCoercibilityDyadicOperatorThrows(SqlCollation col1,
                                                               SqlCollation col2)

Returns the collating sequence (the collation name) and the coercibility for the resulting value of a dyadic operator.

Parameters:

col1 - first operand for the dyadic operation

col2 - second operand for the dyadic operation

Returns:

the resulting collation sequence

Throws:

CalciteException - from CalciteResource.invalidCompare(java.lang.String, java.lang.String, java.lang.String, java.lang.String) or CalciteResource.differentCollations(java.lang.String, java.lang.String) if no collating sequence can be deduced

See Also:

SQL:1999 Part 2 Section 4.2.3 Table 2

getCoercibilityDyadicComparison

public static String getCoercibilityDyadicComparison(SqlCollation col1,
                                                     SqlCollation col2)

Returns the collating sequence (the collation name) to use for the resulting value of a comparison.

Parameters:

col1 - first operand for the dyadic operation

col2 - second operand for the dyadic operation

Returns:

the resulting collation sequence. If no collating sequence could be deduced throws a CalciteResource.invalidCompare(java.lang.String, java.lang.String, java.lang.String, java.lang.String)

See Also:

SQL:1999 Part 2 Section 4.2.3 Table 3

getCoercibilityDyadic

protected static @Nullable SqlCollation getCoercibilityDyadic(SqlCollation col1,
                                                              SqlCollation col2)

Returns the result for getCoercibilityDyadicComparison(org.apache.calcite.sql.SqlCollation, org.apache.calcite.sql.SqlCollation) and getCoercibilityDyadicOperator(org.apache.calcite.sql.SqlCollation, org.apache.calcite.sql.SqlCollation).

toString

public String toString()

Overrides:

toString in class Object

unparse

public void unparse(SqlWriter writer)

getCharset

public Charset getCharset()

getCollationName

public final String getCollationName()

getCoercibility

public final SqlCollation.Coercibility getCoercibility()

getLocale

public final Locale getLocale()

getCollator

@Pure
public @Nullable Collator getCollator()

Returns the Collator to compare values having the current collation, or null if no specific Collator is needed, in which case String.compareTo(java.lang.String) will be used.