Module org.postgresql.pljava

Package org.postgresql.pljava.sqlgen

Class Lexicals.Identifier

java.lang.Object

org.postgresql.pljava.sqlgen.Lexicals.Identifier

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

Lexicals.Identifier.Qualified, Lexicals.Identifier.Unqualified

Enclosing class:

Lexicals

public abstract static class Lexicals.Identifier
extends Object
implements Serializable

Class representing a SQL identifier. These have wild and wooly behavior depending on whether they were represented in the source in quoted form or not. Quoted ones are case-sensitive, and equals will only recognize exact matches. Non-quoted ones match case-insensitively; just to make this interesting, ISO SQL has one set of case-folding rules, while PostgreSQL has another. Also, a non-quoted identifier can match a quoted one, if the quoted one's exact spelling matches the non-quoted one's case-folded form.

For even more fun, the PostgreSQL rules depend on the server encoding. For any multibyte encoding, only the 26 ASCII uppercase letters are folded to lower, leaving all other characters alone. In single-byte encodings, more letters can be touched. But this code has to run in a javac annotation processor without knowledge of any particular database's server encoding. The recommended encoding, UTF-8, is multibyte, so the PostgreSQL rule will be taken to be: only the 26 ASCII letters, always.

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	Lexicals.Identifier.None	What is the name of an unnamed parameter or column?
static class	Lexicals.Identifier.Operator	Class representing an Identifier that names a PostgreSQL operator.
static final class	Lexicals.Identifier.Pseudo	Displays/deparses like a Simple identifier, but no singleton of this class matches anything but itself, to represent pseudo-identifiers like PUBLIC as a privilege grantee.
static class	Lexicals.Identifier.Qualified<T extends Lexicals.Identifier.Unqualified<T>>	Class representing a schema-qualified identifier.
static class	Lexicals.Identifier.Simple	Class representing an unqualified identifier in the form of a name (whether a case-insensitive "regular identifier" without quotes, or a delimited form).
static class	Lexicals.Identifier.Unqualified<T extends Lexicals.Identifier.Unqualified<T>>	Class representing a non-schema-qualified identifier, either the Simple form used for naming most things, or the Operator form specific to PostgreSQL operators.

Method Summary

Modifier and Type	Method	Description
abstract String	deparse(Charset cs)	This Identifier represented as it would be in SQL source.
boolean	equals(Object other)	Equality test with the case-sensitivity rules of SQL.
abstract boolean	equals(Object other, Messager msgr)	For use in an annotation processor, a version of equals that can take a Messager and use it to emit warnings.
boolean	isUnnamed()	Whether this instance represents the name of something unnamed.
String	toString()	Convert to String as by deparse passing a character set of UTF_8.

Methods inherited from class java.lang.Object

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

Method Details

deparse

public abstract String deparse(Charset cs)

This Identifier represented as it would be in SQL source.

The passed Charset indicates the character encoding in which the deparsed result will be stored; the method should verify that the characters can be encoded there, or use the Unicode delimited identifier form and escape the ones that cannot.

Returns:

The identifier, quoted, unless it is folding.

equals

public boolean equals(Object other)

Equality test with the case-sensitivity rules of SQL.

Overrides:

equals in class Object

Parameters:

other - Object to compare to

Returns:

true if two quoted Identifiers match exactly, or two non-quoted ones match in either the PostgreSQL or ISO SQL folded form, or a quoted one exactly matches either folded form of a non-quoted one.

equals

public abstract boolean equals(Object other,
 Messager msgr)

For use in an annotation processor, a version of equals that can take a Messager and use it to emit warnings. It will emit a warning whenever it compares two Identifiers that are equal by one or the other of PostgreSQL's or ISO SQL's rules but not both.

Parameters:

other - Object to compare to

msgr - a Messager to use for warnings; if null, no warnings will be generated.

Returns:

true if two quoted Identifiers match exactly, or two non-quoted ones match in either the PostgreSQL or ISO SQL folded form, or a quoted one exactly matches either folded form of a non-quoted one.

toString

public String toString()

Convert to String as by deparse passing a character set of UTF_8.

Overrides:

toString in class Object

isUnnamed

public boolean isUnnamed()

Whether this instance represents the name of something unnamed.

Returns:

false except where overridden

See Also:

• Lexicals.Identifier.None.isUnnamed()