org.apache.calcite.sql.pretty

Class SqlPrettyWriter

java.lang.Object

org.apache.calcite.sql.pretty.SqlPrettyWriter

All Implemented Interfaces:

SqlWriter

public class SqlPrettyWriter
extends Object
implements SqlWriter

Pretty printer for SQL statements.

There are several options to control the format.

Formatting options

Option	Description	Default
SelectListItemsOnSeparateLines	Whether each item in the select clause is on its own line	false
CaseClausesOnNewLines	Whether the WHEN, THEN and ELSE clauses of a CASE expression appear at the start of a new line.	false
Indentation	Number of spaces to indent	4
KeywordsLowerCase	Whether to print keywords (SELECT, AS, etc.) in lower-case.	false
ParenthesizeAllExprs	Whether to enclose all expressions in parentheses, even if the operator has high enough precedence that the parentheses are not required. For example, the parentheses are required in the expression (a + b) c because the '*' operator has higher precedence than the '+' operator, and so without the parentheses, the expression would be equivalent to a + (b * c). The fully-parenthesized expression, ((a + b) * c) is unambiguous even if you don't know the precedence of every operator.
QuoteAllIdentifiers	Whether to quote all identifiers, even those which would be correct according to the rules of the SqlDialect if quotation marks were omitted.	true
SelectListItemsOnSeparateLines	Whether each item in the select clause is on its own line.	false
SubqueryStyle	Style for formatting sub-queries. Values are: Hyde, Black.	Hyde
LineLength	Set the desired maximum length for lines (to look nice in editors, printouts, etc.).	0

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	SqlPrettyWriter.FrameImpl Implementation of SqlWriter.Frame.

Nested classes/interfaces inherited from interface org.apache.calcite.sql.SqlWriter

SqlWriter.Frame, SqlWriter.FrameType, SqlWriter.FrameTypeEnum, SqlWriter.SubqueryStyle

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	alwaysUseParentheses
protected SqlPrettyWriter.FrameImpl	frame
protected static CalciteLogger	LOGGER
protected String	nextWhitespace
protected static String	NL
protected PrintWriter	pw

Constructor Summary

Constructors

Constructor and Description
SqlPrettyWriter(SqlDialect dialect)
SqlPrettyWriter(SqlDialect dialect, boolean alwaysUseParentheses)
SqlPrettyWriter(SqlDialect dialect, boolean alwaysUseParentheses, PrintWriter pw)

Method Summary

Methods

Modifier and Type	Method and Description
protected SqlPrettyWriter.FrameImpl	createListFrame(SqlWriter.FrameType frameType, String keyword, String open, String close) Creates a list frame.
void	describe(PrintWriter pw, boolean omitDefaults) Prints the property settings of this pretty-writer to a writer.
void	endFunCall(SqlWriter.Frame frame) Ends a list which is a call to a function.
void	endList(SqlWriter.Frame frame) Ends a list.
String	format(SqlNode node)
SqlDialect	getDialect() Returns the dialect of SQL.
int	getIndentation() Returns the offset for each level of indentation.
int	getLineLength()
void	identifier(String name) Prints an identifier, quoting as necessary.
boolean	inQuery() Returns whether we are currently in a query context (SELECT, INSERT, UNION, INTERSECT, EXCEPT, and the ORDER BY operator).
boolean	isAlwaysUseParentheses() Returns whether to enclose all expressions in parentheses, even if the operator has high enough precedence that the parentheses are not required.
boolean	isClauseStartsLine() Returns whether this writer should start each clause (e.g.
boolean	isKeywordsLowerCase() Returns whether to output all keywords (e.g.
boolean	isQuoteAllIdentifiers() Returns whether this writer should quote all identifiers, even those that do not contain mixed-case identifiers or punctuation.
boolean	isSelectListExtraIndentFlag()
boolean	isSelectListItemsOnSeparateLines() Returns whether the items in the SELECT clause should each be on a separate line.
boolean	isWhereListItemsOnSeparateLines()
void	keyword(String s) Prints a sequence of keywords.
void	literal(String s) Prints a literal, exactly as provided.
void	newlineAndIndent() Prints a new line, and indents.
void	print(int x) Prints an integer.
void	print(String s) Prints a string, preceded by whitespace if necessary.
void	reset() Resets this writer so that it can format another expression.
void	resetSettings() Resets all properties to their default values.
void	sep(String sep) Writes a list separator, unless the separator is "," and this is the first occurrence in the list.
void	sep(String sep, boolean printFirst) Writes a list separator.
void	setAlwaysUseParentheses(boolean b)
void	setCaseClausesOnNewLines(boolean caseClausesOnNewLines) Sets whether the WHEN, THEN and ELSE clauses of a CASE expression appear at the start of a new line.
void	setClauseStartsLine(boolean clauseStartsLine) Sets whether a clause (FROM, WHERE, GROUP BY, HAVING, WINDOW, ORDER BY) starts a new line.
void	setFormatOptions(SqlFormatOptions options)
void	setIndentation(int indentation) Sets the number of spaces indentation.
void	setKeywordsLowerCase(boolean b) Sets whether to print keywords (SELECT, AS, etc.) in lower-case.
void	setLineLength(int lineLength)
void	setNeedWhitespace(boolean needWhitespace) Sets whether whitespace is needed before the next token.
void	setQuoteAllIdentifiers(boolean b) Sets whether to quote all identifiers, even those which would be correct according to the rules of the SqlDialect if quotation marks were omitted.
void	setSelectListExtraIndentFlag(boolean b) Sets whether to use a fix for SELECT list indentations.
void	setSelectListItemsOnSeparateLines(boolean b) Sets whether each item in a SELECT list, GROUP BY list, or ORDER BY list is on its own line.
void	setSettings(Properties properties) Sets settings from a properties object.
void	setSubqueryStyle(SqlWriter.SubqueryStyle subqueryStyle) Sets the subquery style.
void	setWhereListItemsOnSeparateLines(boolean b) Sets whether to print a newline before each AND or OR (whichever is higher level) in WHERE clauses.
void	setWindowDeclListNewline(boolean windowDeclListNewline)
void	setWindowNewline(boolean windowNewline)
SqlWriter.Frame	startFunCall(String funName) Starts a list which is a call to a function.
SqlWriter.Frame	startList(SqlWriter.FrameTypeEnum frameType) Starts a list with no opening string.
SqlWriter.Frame	startList(SqlWriter.FrameType frameType, String open, String close) Starts a list.
protected SqlWriter.Frame	startList(SqlWriter.FrameType frameType, String keyword, String open, String close) Starts a list.
SqlWriter.Frame	startList(String open, String close) Starts a list.
protected boolean	tooLong(String s)
SqlString	toSqlString() Returns the contents of this writer as a 'certified kocher' SQL string.
String	toString()
protected void	whiteSpace()

Methods inherited from class java.lang.Object

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

Field Detail

LOGGER

protected static final CalciteLogger LOGGER

NL

protected static final String NL

pw

protected final PrintWriter pw

frame

protected SqlPrettyWriter.FrameImpl frame

nextWhitespace

protected String nextWhitespace

alwaysUseParentheses

protected boolean alwaysUseParentheses

Constructor Detail

SqlPrettyWriter

public SqlPrettyWriter(SqlDialect dialect,
               boolean alwaysUseParentheses,
               PrintWriter pw)

SqlPrettyWriter

public SqlPrettyWriter(SqlDialect dialect,
               boolean alwaysUseParentheses)

SqlPrettyWriter

public SqlPrettyWriter(SqlDialect dialect)

Method Detail

setCaseClausesOnNewLines

public void setCaseClausesOnNewLines(boolean caseClausesOnNewLines)

Sets whether the WHEN, THEN and ELSE clauses of a CASE expression appear at the start of a new line. The default is false.

setSubqueryStyle

public void setSubqueryStyle(SqlWriter.SubqueryStyle subqueryStyle)

Sets the subquery style. Default is SqlWriter.SubqueryStyle.HYDE.

setWindowNewline

public void setWindowNewline(boolean windowNewline)

setWindowDeclListNewline

public void setWindowDeclListNewline(boolean windowDeclListNewline)

getIndentation

public int getIndentation()

Description copied from interface: SqlWriter

Returns the offset for each level of indentation. Default 4.

Specified by:

getIndentation in interface SqlWriter

isAlwaysUseParentheses

public boolean isAlwaysUseParentheses()

Description copied from interface: SqlWriter

Returns whether to enclose all expressions in parentheses, even if the operator has high enough precedence that the parentheses are not required.

For example, the parentheses are required in the expression (a + b) * c because the '*' operator has higher precedence than the '+' operator, and so without the parentheses, the expression would be equivalent to a + (b * c). The fully-parenthesized expression, ((a + b) * c) is unambiguous even if you don't know the precedence of every operator.

Specified by:

isAlwaysUseParentheses in interface SqlWriter

inQuery

public boolean inQuery()

Description copied from interface: SqlWriter

Returns whether we are currently in a query context (SELECT, INSERT, UNION, INTERSECT, EXCEPT, and the ORDER BY operator).

Specified by:

inQuery in interface SqlWriter

isQuoteAllIdentifiers

public boolean isQuoteAllIdentifiers()

Description copied from interface: SqlWriter

Returns whether this writer should quote all identifiers, even those that do not contain mixed-case identifiers or punctuation.

Specified by:

isQuoteAllIdentifiers in interface SqlWriter

Returns:

whether to quote all identifiers

isClauseStartsLine

public boolean isClauseStartsLine()

Description copied from interface: SqlWriter

Returns whether this writer should start each clause (e.g. GROUP BY) on a new line.

Specified by:

isClauseStartsLine in interface SqlWriter

Returns:

whether to start each clause on a new line

isSelectListItemsOnSeparateLines

public boolean isSelectListItemsOnSeparateLines()

Description copied from interface: SqlWriter

Returns whether the items in the SELECT clause should each be on a separate line.

Specified by:

isSelectListItemsOnSeparateLines in interface SqlWriter

Returns:

whether to put each SELECT clause item on a new line

isWhereListItemsOnSeparateLines

public boolean isWhereListItemsOnSeparateLines()

isSelectListExtraIndentFlag

public boolean isSelectListExtraIndentFlag()

isKeywordsLowerCase

public boolean isKeywordsLowerCase()

Description copied from interface: SqlWriter

Returns whether to output all keywords (e.g. SELECT, GROUP BY) in lower case.

Specified by:

isKeywordsLowerCase in interface SqlWriter

Returns:

whether to output SQL keywords in lower case

getLineLength

public int getLineLength()

resetSettings

public void resetSettings()

Description copied from interface: SqlWriter

Resets all properties to their default values.

Specified by:

resetSettings in interface SqlWriter

reset

public void reset()

Description copied from interface: SqlWriter

Resets this writer so that it can format another expression. Does not affect formatting preferences (see SqlWriter.resetSettings()

Specified by:

reset in interface SqlWriter

setIndentation

public void setIndentation(int indentation)

Sets the number of spaces indentation.

See Also:

getIndentation()

describe

public void describe(PrintWriter pw,
            boolean omitDefaults)

Prints the property settings of this pretty-writer to a writer.

Parameters:

pw - Writer

omitDefaults - Whether to omit properties whose value is the same as the default

setSettings

public void setSettings(Properties properties)

Sets settings from a properties object.

setClauseStartsLine

public void setClauseStartsLine(boolean clauseStartsLine)

Sets whether a clause (FROM, WHERE, GROUP BY, HAVING, WINDOW, ORDER BY) starts a new line. Default is true. SELECT is always at the start of a line.

setSelectListItemsOnSeparateLines

public void setSelectListItemsOnSeparateLines(boolean b)

Sets whether each item in a SELECT list, GROUP BY list, or ORDER BY list is on its own line. Default false.

setSelectListExtraIndentFlag

public void setSelectListExtraIndentFlag(boolean b)

Sets whether to use a fix for SELECT list indentations.

• If set to "false":

   SELECT
       A as A
           B as B
           C as C
       D
   

• If set to "true":

   SELECT
       A as A
       B as B
       C as C
       D
   

setKeywordsLowerCase

public void setKeywordsLowerCase(boolean b)

Sets whether to print keywords (SELECT, AS, etc.) in lower-case. The default is false: keywords are printed in upper-case.

setWhereListItemsOnSeparateLines

public void setWhereListItemsOnSeparateLines(boolean b)

Sets whether to print a newline before each AND or OR (whichever is higher level) in WHERE clauses. NOTE: Ignored when alwaysUseParentheses is set to true.

setAlwaysUseParentheses

public void setAlwaysUseParentheses(boolean b)

newlineAndIndent

public void newlineAndIndent()

Description copied from interface: SqlWriter

Prints a new line, and indents.

Specified by:

newlineAndIndent in interface SqlWriter

setQuoteAllIdentifiers

public void setQuoteAllIdentifiers(boolean b)

Sets whether to quote all identifiers, even those which would be correct according to the rules of the SqlDialect if quotation marks were omitted.

Default true.

createListFrame

protected SqlPrettyWriter.FrameImpl createListFrame(SqlWriter.FrameType frameType,
                                        String keyword,
                                        String open,
                                        String close)

Creates a list frame.

Derived classes should override this method to specify the indentation of the list.

Parameters:

frameType - What type of list

keyword - The keyword to be printed at the start of the list

open - The string to print at the start of the list

close - The string to print at the end of the list

Returns:

A frame

startList

protected SqlWriter.Frame startList(SqlWriter.FrameType frameType,
                        String keyword,
                        String open,
                        String close)

Starts a list.

Parameters:

frameType - Type of list. For example, a SELECT list will be governed according to SELECT-list formatting preferences.

open - String to print at the start of the list; typically "(" or the empty string.

close - String to print at the end of the list.

endList

public void endList(SqlWriter.Frame frame)

Description copied from interface: SqlWriter

Ends a list.

Specified by:

endList in interface SqlWriter

Parameters:

frame - The frame which was created by SqlWriter.startList(java.lang.String, java.lang.String).

format

public String format(SqlNode node)

toString

public String toString()

Overrides:

toString in class Object

toSqlString

public SqlString toSqlString()

Description copied from interface: SqlWriter

Returns the contents of this writer as a 'certified kocher' SQL string.

Specified by:

toSqlString in interface SqlWriter

Returns:

SQL string

getDialect

public SqlDialect getDialect()

Description copied from interface: SqlWriter

Returns the dialect of SQL.

Specified by:

getDialect in interface SqlWriter

Returns:

SQL dialect

literal

public void literal(String s)

Description copied from interface: SqlWriter

Prints a literal, exactly as provided. Does not attempt to indent or convert to upper or lower case. Does not add quotation marks. Adds preceding whitespace if necessary.

Specified by:

literal in interface SqlWriter

keyword

public void keyword(String s)

Description copied from interface: SqlWriter

Prints a sequence of keywords. Must not start or end with space, but may contain a space. For example, keyword("SELECT"), keyword("CHARACTER SET").

Specified by:

keyword in interface SqlWriter

whiteSpace

protected void whiteSpace()

tooLong

protected boolean tooLong(String s)

print

public void print(String s)

Description copied from interface: SqlWriter

Prints a string, preceded by whitespace if necessary.

Specified by:

print in interface SqlWriter

print

public void print(int x)

Description copied from interface: SqlWriter

Prints an integer.

Specified by:

print in interface SqlWriter

Parameters:

x - Integer

identifier

public void identifier(String name)

Description copied from interface: SqlWriter

Prints an identifier, quoting as necessary.

Specified by:

identifier in interface SqlWriter

startFunCall

public SqlWriter.Frame startFunCall(String funName)

Description copied from interface: SqlWriter

Starts a list which is a call to a function.

Specified by:

startFunCall in interface SqlWriter

See Also:

SqlWriter.endFunCall(Frame)

endFunCall

public void endFunCall(SqlWriter.Frame frame)

Description copied from interface: SqlWriter

Ends a list which is a call to a function.

Specified by:

endFunCall in interface SqlWriter

Parameters:

frame - Frame

See Also:

SqlWriter.startFunCall(String)

startList

public SqlWriter.Frame startList(String open,
                        String close)

Description copied from interface: SqlWriter

Starts a list.

Specified by:

startList in interface SqlWriter

startList

public SqlWriter.Frame startList(SqlWriter.FrameTypeEnum frameType)

Description copied from interface: SqlWriter

Starts a list with no opening string.

Specified by:

startList in interface SqlWriter

Parameters:

frameType - Type of list. For example, a SELECT list will be

startList

public SqlWriter.Frame startList(SqlWriter.FrameType frameType,
                        String open,
                        String close)

Description copied from interface: SqlWriter

Starts a list.

Specified by:

startList in interface SqlWriter

Parameters:

frameType - Type of list. For example, a SELECT list will be governed according to SELECT-list formatting preferences.

open - String to start the list; typically "(" or the empty string.

close - String to close the list

sep

public void sep(String sep)

Description copied from interface: SqlWriter

Writes a list separator, unless the separator is "," and this is the first occurrence in the list.

Specified by:

sep in interface SqlWriter

Parameters:

sep - List separator, typically ",".

sep

public void sep(String sep,
       boolean printFirst)

Description copied from interface: SqlWriter

Writes a list separator.

Specified by:

sep in interface SqlWriter

Parameters:

sep - List separator, typically ","

printFirst - Whether to print the first occurrence of the separator

setNeedWhitespace

public void setNeedWhitespace(boolean needWhitespace)

Description copied from interface: SqlWriter

Sets whether whitespace is needed before the next token.

Specified by:

setNeedWhitespace in interface SqlWriter

setLineLength

public void setLineLength(int lineLength)

setFormatOptions

public void setFormatOptions(SqlFormatOptions options)