org.postgresql.core

Class Parser

java.lang.Object

org.postgresql.core.Parser

public class Parser
extends Object

Basic query parser infrastructure. Note: This class should not be considered as pgjdbc public API.

Author:

Michael Paesold ([email protected]), Christopher Deckers ([email protected])

Constructor Summary

Constructors

Constructor and Description
Parser()

Method Summary

Methods

Modifier and Type	Method and Description
static boolean	charTerminatesIdentifier(char c)
static boolean	isDollarQuoteContChar(char c) Checks if a character is valid as the second or later character of a dollar quoting tag.
static boolean	isDollarQuoteStartChar(char c) Checks if a character is valid as the start of a dollar quoting tag.
static boolean	isIdentifierContChar(char c) Checks if a character is valid as the second or later character of an identifier.
static boolean	isIdentifierStartChar(char c) Checks if a character is valid as the start of an identifier.
static boolean	isOperatorChar(char c)
static boolean	isSpace(char c)
static JdbcCallParseInfo	modifyJdbcCall(String jdbcSql, boolean stdStrings, int serverVersion, int protocolVersion) Converts JDBC-specific callable statement escapes { [? =] call <some_function> [(?, [?,..])] } into the PostgreSQL format which is select <some_function> (?, [?, ...]) as result or select * from <some_function> (?, [?, ...]) as result (7.3)
static int	parseBlockComment(char[] query, int offset) Test if the / character at offset starts a block comment, and return the position of the last / character.
static boolean	parseDeleteKeyword(char[] query, int offset) Parse string to check presence of DELETE keyword regardless of case.
static int	parseDollarQuotes(char[] query, int offset) Test if the dollar character ($) at the given offset starts a dollar-quoted string and return the offset of the ending dollar character.
static int	parseDoubleQuotes(char[] query, int offset) Find the end of the double-quoted string starting at the given offset.
static boolean	parseInsertKeyword(char[] query, int offset) Parse string to check presence of INSERT keyword regardless of case.
static List<NativeQuery>	parseJdbcSql(String query, boolean standardConformingStrings, boolean withParameters, boolean splitStatements, boolean isBatchedReWriteConfigured, String... returningColumnNames) Parses JDBC query into PostgreSQL's native format.
static int	parseLineComment(char[] query, int offset) Test if the - character at offset starts a -- style line comment, and return the position of the first \r or \n character.
static boolean	parseMoveKeyword(char[] query, int offset) Parse string to check presence of MOVE keyword regardless of case.
static boolean	parseReturningKeyword(char[] query, int offset) Parse string to check presence of RETURNING keyword regardless of case.
static boolean	parseSelectKeyword(char[] query, int offset) Parse string to check presence of SELECT keyword regardless of case.
static int	parseSingleQuotes(char[] query, int offset, boolean standardConformingStrings) Find the end of the single-quoted string starting at the given offset.
static boolean	parseUpdateKeyword(char[] query, int offset) Parse string to check presence of UPDATE keyword regardless of case.
static boolean	parseValuesKeyword(char[] query, int offset) Parse string to check presence of VALUES keyword regardless of case.
static boolean	parseWithKeyword(char[] query, int offset) Parse string to check presence of WITH keyword regardless of case.
static String	replaceProcessing(String p_sql, boolean replaceProcessingEnabled, boolean standardConformingStrings) Filter the SQL string of Java SQL Escape clauses.

Methods inherited from class java.lang.Object

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

Constructor Detail

Parser

public Parser()

Method Detail

parseJdbcSql

public static List<NativeQuery> parseJdbcSql(String query,
                             boolean standardConformingStrings,
                             boolean withParameters,
                             boolean splitStatements,
                             boolean isBatchedReWriteConfigured,
                             String... returningColumnNames)
                                      throws SQLException

Parses JDBC query into PostgreSQL's native format. Several queries might be given if separated by semicolon.

Parameters:

query - jdbc query to parse

standardConformingStrings - whether to allow backslashes to be used as escape characters in single quote literals

withParameters - whether to replace ?, ? with $1, $2, etc

splitStatements - whether to split statements by semicolon

isBatchedReWriteConfigured - whether re-write optimization is enabled

returningColumnNames - for simple insert, update, delete add returning with given column names

Returns:

list of native queries

Throws:

SQLException - if unable to add returning clause (invalid column names)

parseSingleQuotes

public static int parseSingleQuotes(char[] query,
                    int offset,
                    boolean standardConformingStrings)

Find the end of the single-quoted string starting at the given offset. Note: for 'single '' quote in string', this method currently returns the offset of first ' character after the initial one. The caller must call the method a second time for the second part of the quoted string.

Parameters:

query - query

offset - start offset

standardConformingStrings - standard conforming strings

Returns:

position of the end of the single-quoted string

parseDoubleQuotes

public static int parseDoubleQuotes(char[] query,
                    int offset)

Find the end of the double-quoted string starting at the given offset. Note: for "double "" quote in string", this method currently returns the offset of first " character after the initial one. The caller must call the method a second time for the second part of the quoted string.

Parameters:

query - query

offset - start offset

Returns:

position of the end of the double-quoted string

parseDollarQuotes

public static int parseDollarQuotes(char[] query,
                    int offset)

Test if the dollar character ($) at the given offset starts a dollar-quoted string and return the offset of the ending dollar character.

Parameters:

query - query

offset - start offset

Returns:

offset of the ending dollar character

parseLineComment

public static int parseLineComment(char[] query,
                   int offset)

Test if the - character at offset starts a -- style line comment, and return the position of the first \r or \n character.

Parameters:

query - query

offset - start offset

Returns:

position of the first \r or \n character

parseBlockComment

public static int parseBlockComment(char[] query,
                    int offset)

Test if the / character at offset starts a block comment, and return the position of the last / character.

Parameters:

query - query

offset - start offset

Returns:

position of the last / character

parseDeleteKeyword

public static boolean parseDeleteKeyword(char[] query,
                         int offset)

Parse string to check presence of DELETE keyword regardless of case. The initial character is assumed to have been matched.

Parameters:

query - char[] of the query statement

offset - position of query to start checking

Returns:

boolean indicates presence of word

parseInsertKeyword

public static boolean parseInsertKeyword(char[] query,
                         int offset)

Parse string to check presence of INSERT keyword regardless of case.

Parameters:

query - char[] of the query statement

offset - position of query to start checking

Returns:

boolean indicates presence of word

parseMoveKeyword

public static boolean parseMoveKeyword(char[] query,
                       int offset)

Parse string to check presence of MOVE keyword regardless of case.

Parameters:

query - char[] of the query statement

offset - position of query to start checking

Returns:

boolean indicates presence of word

parseReturningKeyword

public static boolean parseReturningKeyword(char[] query,
                            int offset)

Parse string to check presence of RETURNING keyword regardless of case.

Parameters:

query - char[] of the query statement

offset - position of query to start checking

Returns:

boolean indicates presence of word

parseSelectKeyword

public static boolean parseSelectKeyword(char[] query,
                         int offset)

Parse string to check presence of SELECT keyword regardless of case.

Parameters:

query - char[] of the query statement

offset - position of query to start checking

Returns:

boolean indicates presence of word

parseUpdateKeyword

public static boolean parseUpdateKeyword(char[] query,
                         int offset)

Parse string to check presence of UPDATE keyword regardless of case.

Parameters:

query - char[] of the query statement

offset - position of query to start checking

Returns:

boolean indicates presence of word

parseValuesKeyword

public static boolean parseValuesKeyword(char[] query,
                         int offset)

Parse string to check presence of VALUES keyword regardless of case.

Parameters:

query - char[] of the query statement

offset - position of query to start checking

Returns:

boolean indicates presence of word

parseWithKeyword

public static boolean parseWithKeyword(char[] query,
                       int offset)

Parse string to check presence of WITH keyword regardless of case.

Parameters:

query - char[] of the query statement

offset - position of query to start checking

Returns:

boolean indicates presence of word

isSpace

public static boolean isSpace(char c)

Parameters:

c - character

Returns:

true if the character is a whitespace character as defined in the backend's parser

isOperatorChar

public static boolean isOperatorChar(char c)

Parameters:

c - character

Returns:

true if the given character is a valid character for an operator in the backend's parser

isIdentifierStartChar

public static boolean isIdentifierStartChar(char c)

Checks if a character is valid as the start of an identifier. PostgreSQL 9.4 allows column names like _, ‿, ⁀, ⁔, ︳, ︴, ﹍, ﹎, ﹏, ＿, so it is assumed isJavaIdentifierPart is good enough for PostgreSQL.

Parameters:

c - the character to check

Returns:

true if valid as first character of an identifier; false if not

See Also:

Identifiers and Key Words

isIdentifierContChar

public static boolean isIdentifierContChar(char c)

Checks if a character is valid as the second or later character of an identifier.

Parameters:

c - the character to check

Returns:

true if valid as second or later character of an identifier; false if not

charTerminatesIdentifier

public static boolean charTerminatesIdentifier(char c)

Parameters:

c - character

Returns:

true if the character terminates an identifier

isDollarQuoteStartChar

public static boolean isDollarQuoteStartChar(char c)

Checks if a character is valid as the start of a dollar quoting tag.

Parameters:

c - the character to check

Returns:

true if valid as first character of a dollar quoting tag; false if not

isDollarQuoteContChar

public static boolean isDollarQuoteContChar(char c)

Checks if a character is valid as the second or later character of a dollar quoting tag.

Parameters:

c - the character to check

Returns:

true if valid as second or later character of a dollar quoting tag; false if not

modifyJdbcCall

public static JdbcCallParseInfo modifyJdbcCall(String jdbcSql,
                               boolean stdStrings,
                               int serverVersion,
                               int protocolVersion)
                                        throws SQLException

Converts JDBC-specific callable statement escapes { [? =] call <some_function> [(?, [?,..])] } into the PostgreSQL format which is select <some_function> (?, [?, ...]) as result or select * from <some_function> (?, [?, ...]) as result (7.3)

Parameters:

jdbcSql - sql text with JDBC escapes

stdStrings - if backslash in single quotes should be regular character or escape one

serverVersion - server version

protocolVersion - protocol version

Returns:

SQL in appropriate for given server format

Throws:

SQLException - if given SQL is malformed

replaceProcessing

public static String replaceProcessing(String p_sql,
                       boolean replaceProcessingEnabled,
                       boolean standardConformingStrings)
                                throws SQLException

Filter the SQL string of Java SQL Escape clauses.

Currently implemented Escape clauses are those mentioned in 11.3 in the specification. Basically we look through the sql string for {d xxx}, {t xxx}, {ts xxx}, {oj xxx} or {fn xxx} in non-string sql code. When we find them, we just strip the escape part leaving only the xxx part. So, something like "select * from x where d={d '2001-10-09'}" would return "select * from x where d= '2001-10-09'".

Parameters:

p_sql - the original query text

replaceProcessingEnabled - whether replace_processing_enabled is on

standardConformingStrings - whether standard_conforming_strings is on

Returns:

PostgreSQL-compatible SQL

Throws:

SQLException - if given SQL is wrong