org.checkerframework.framework.util

Class JavaExpressionParseUtil

java.lang.Object

org.checkerframework.framework.util.JavaExpressionParseUtil

public class JavaExpressionParseUtil
extends Object

Helper methods to parse a string that represents a restricted Java expression.

See the Checker Framework Manual:

Writing Java expressions as annotation arguments, Annotations whose argument is a Java expression (dependent type annotations)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	JavaExpressionParseUtil.JavaExpressionContext Context used to parse and viewpoint-adapt a Java expression.
static class	JavaExpressionParseUtil.JavaExpressionParseException An exception that indicates a parse error.

Field Summary

Fields

Modifier and Type	Field and Description
protected static Pattern	ANCHORED_PARAMETER_PATTERN Anchored pattern for a formal parameter use.
protected static String	PARAMETER_REGEX Regular expression for a formal parameter use.
protected static Pattern	UNANCHORED_PARAMETER_PATTERN Unanchored; can be used to find all formal parameter uses.

Constructor Summary

Constructors

Constructor and Description
JavaExpressionParseUtil()

Method Summary

Modifier and Type	Method and Description
static int	parameterIndex(String s) Returns the 1-based index of the formal parameter that occurs in s or -1 if no formal parameter occurs.
static List<Integer>	parameterIndices(String s) Returns a list of 1-based indices of all formal parameters that occur in s.
static JavaExpression	parse(String expression, JavaExpressionParseUtil.JavaExpressionContext context) Parse a string and viewpoint-adapt it to the given context.
static JavaExpression	parse(String expression, JavaExpressionParseUtil.JavaExpressionContext context, @Nullable TreePath localPath) Parse a string with respect to localPath and viewpoint-adapt it to the given context.

Methods inherited from class java.lang.Object

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

Field Detail

PARAMETER_REGEX

protected static final String PARAMETER_REGEX

Regular expression for a formal parameter use.

See Also:

Constant Field Values

ANCHORED_PARAMETER_PATTERN

protected static final Pattern ANCHORED_PARAMETER_PATTERN

Anchored pattern for a formal parameter use.

UNANCHORED_PARAMETER_PATTERN

protected static final Pattern UNANCHORED_PARAMETER_PATTERN

Unanchored; can be used to find all formal parameter uses.

Constructor Detail

JavaExpressionParseUtil

public JavaExpressionParseUtil()

Method Detail

parse

public static JavaExpression parse(String expression,
                                   JavaExpressionParseUtil.JavaExpressionContext context)
                            throws JavaExpressionParseUtil.JavaExpressionParseException

Parse a string and viewpoint-adapt it to the given context. Return its representation as a JavaExpression, or throw a JavaExpressionParseUtil.JavaExpressionParseException.

Parameters:

expression - a Java expression to parse

context - information about any receiver and arguments; also has a reference to the checker

Returns:

the JavaExpression for the given string

Throws:

JavaExpressionParseUtil.JavaExpressionParseException - if the string cannot be parsed

parse

public static JavaExpression parse(String expression,
                                   JavaExpressionParseUtil.JavaExpressionContext context,
                                   @Nullable TreePath localPath)
                            throws JavaExpressionParseUtil.JavaExpressionParseException

Parse a string with respect to localPath and viewpoint-adapt it to the given context. Return its representation as a JavaExpression, or throw a JavaExpressionParseUtil.JavaExpressionParseException.

If localPath is non-null, then identifiers are parsed as if the expression was written at the location of localPath. This means identifiers will be parsed to local variables in scope at localPath when possible. If localPath is null, then no identifier can be parsed to a local variable. In either case, the parameter syntax, e.g. #1, is always parsed to the arguments in context. This is because a parameter of a lambda can refer both to local variables in scope at its declaration and to a parameter of the lambda.

Parameters:

expression - a Java expression to parse

context - information about any receiver and arguments; also has a reference to the checker

localPath - if non-null, the expression is parsed as if it were written at this location

Returns:

the JavaExpression for the given string

Throws:

JavaExpressionParseUtil.JavaExpressionParseException - if the string cannot be parsed

parameterIndices

public static List<Integer> parameterIndices(String s)

Returns a list of 1-based indices of all formal parameters that occur in s. Each formal parameter occurs in s as a string like "#1" or "#4". This routine does not do proper parsing; for instance, if "#2" appears within a string in s, then 2 is in the result list. The result may contain duplicates.

Parameters:

s - a Java expression

Returns:

a list of 1-based indices of all formal parameters that occur in s

parameterIndex

public static int parameterIndex(String s)

Returns the 1-based index of the formal parameter that occurs in s or -1 if no formal parameter occurs.

Parameters:

s - a Java expression

Returns:

the 1-based indices of the formal parameter that occur in s or -1