CharacterRangeInfo (Java SE 25 & JDK 25)
Description: declaration: module: java.base, package: java.lang.classfile.attribute, interface: CharacterRangeInfo
Keywords: java.lang.classfile.attribute.CharacterRangeInfo interface

# Interface CharacterRangeInfo

public sealed interface CharacterRangeInfo
Models a single character range entry in the `CharacterRangeTableAttribute`.

Each character range entry associates a range of indices in the code array with a range of character positions in the source file. A character position in the source file is represented by a line number and a column number, and its value is encoded as `lineNumber << 10 + columnNumber`. Note that column numbers are not the same as byte indices in a column as multibyte characters may be present in the source file. Each character range entry includes a flag which indicates what kind of range is described: statement, assignment, method call, etc.

Since:
  24
See Also:
  - `CharacterRangeTableAttribute.characterRangeTable()`
  - `CharacterRange`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `int`
  `characterRangeEnd()`
  Returns the encoded end of character positions in the source file, exclusive.
  `int`
  `characterRangeStart()`
  Returns the encoded start of character positions in the source file, inclusive.
  `int`
  `endPc()`
  Returns the end of indices in the code array, exclusive.
  `int`
  `flags()`
  Returns the flags of this character range entry.
  `static CharacterRangeInfo`
  `of(int startPc, int endPc, int characterRangeStart, int characterRangeEnd, int flags)`
  Returns a character range entry.
  `int`
  `startPc()`
  Returns the start of indices in the code array, inclusive.

- ## Method Details

  - ### startPc

    int startPc()
    Returns the start of indices in the code array, inclusive.
    Returns:
      the start of indices in the code array, inclusive
    See Also:
      - `CharacterRange.startScope()`

  - ### endPc

    int endPc()
    Returns the end of indices in the code array, exclusive.
    Returns:
      the end of indices in the code array, exclusive
    See Also:
      - `CharacterRange.endScope()`

  - ### characterRangeStart

    int characterRangeStart()
    Returns the encoded start of character positions in the source file, inclusive.
    Returns:
      the encoded start of character positions in the source file, inclusive

  - ### characterRangeEnd

    int characterRangeEnd()
    Returns the encoded end of character positions in the source file, exclusive.
    Returns:
      the encoded end of character positions in the source file, exclusive

  - ### flags

    int flags()
    Returns the flags of this character range entry.

    The value of the flags item describes the kind of range. Multiple flags may be set within flags.

    - `CharacterRange.FLAG_STATEMENT` Range is a Statement (except ExpressionStatement), StatementExpression (JLS 14.8), as well as each `VariableDeclaratorId = VariableInitializer` of LocalVariableDeclarationStatement (JLS 14.4) or FieldDeclaration (JLS 8.3) in the grammar.
    - `CharacterRange.FLAG_BLOCK` Range is a Block in the grammar.
    - `CharacterRange.FLAG_ASSIGNMENT` Range is an assignment expression - `Expression1 AssignmentOperator Expression1` in the grammar as well as increment and decrement expressions (both prefix and postfix).
    - `CharacterRange.FLAG_FLOW_CONTROLLER` An expression whose value will affect control flow. `Flowcon` in the following:

          if ( Flowcon ) Statement [else Statement]
          for ( ForInitOpt ; [Flowcon] ; ForUpdateOpt ) Statement
          while ( Flowcon ) Statement
          do Statement while ( Flowcon ) ;
          switch ( Flowcon ) { SwitchBlockStatementGroups }
          Flowcon || Expression3
          Flowcon && Expression3
          Flowcon ? Expression : Expression1

    - `CharacterRange.FLAG_FLOW_TARGET` Statement or expression effected by a CRT_FLOW_CONTROLLER. `Flowtarg` in the following:

          if ( Flowcon ) Flowtarg [else Flowtarg]
          for ( ForInitOpt ; [Flowcon] ; ForUpdateOpt ) Flowtarg
          while ( Flowcon ) Flowtarg
          do Flowtarg while ( Flowcon ) ;
          Flowcon || Flowtarg
          Flowcon && Flowtarg
          Flowcon ? Flowtarg : Flowtarg

    - `CharacterRange.FLAG_INVOKE` Method invocation. For example: Identifier Arguments.
    - `CharacterRange.FLAG_CREATE` New object creation. For example: new Creator.
    - `CharacterRange.FLAG_BRANCH_TRUE` A condition encoded in the branch instruction immediately contained in the code range for this item is not inverted towards the corresponding branch condition in the source code. I.e. actual jump occurs if and only if the the source code branch condition evaluates to true. Entries of this type are produced only for conditions that are listed in the description of CRT_FLOW_CONTROLLER flag. The source range for the entry contains flow controlling expression. start_pc field for an entry of this type must point to a branch instruction: if_acmp<cond>, if_icmp<cond>, if<cond>, ifnonull, ifnull or goto. CRT_BRANCH_TRUE and CRT_BRANCH_FALSE are special kinds of entries that can be used to determine what branch of a condition was chosen during the runtime.
    - `CharacterRange.FLAG_BRANCH_FALSE` A condition encoded in the branch instruction immediately contained in the code range for this item is inverted towards the corresponding branch condition in the source code. I.e. actual jump occurs if and only if the the source code branch condition evaluates to false. Entries of this type are produced only for conditions that are listed in the description of CRT_FLOW_CONTROLLER flag. The source range for the entry contains flow controlling expression. start_pc field for an entry of this type must point to a branch instruction: if_acmp<cond>, if_icmp<cond>, if<cond>, ifnonull, ifnull or goto.

    All bits of the flags item not assigned above are reserved for future use. They should be set to zero in generated class files and should be ignored by Java virtual machine implementations.

    Returns:
      the flags of this character range entry
    See Also:
      - `CharacterRange.flags()`

  - ### of

    static CharacterRangeInfo of(int startPc, int endPc, int characterRangeStart, int characterRangeEnd, int flags)
    Returns a character range entry.
    API Note:
      The created entry cannot be written to a `CodeBuilder`. Use `CodeBuilder::characterRange` instead.
    Parameters:
      `startPc` - the start of indices in the code array, inclusive
      `endPc` - the end of indices in the code array, exclusive
      `characterRangeStart` - the encoded start of character positions in the source file, inclusive
      `characterRangeEnd` - the encoded end of character positions in the source file, exclusive
      `flags` - the flags of this entry
    Returns:
      a character range entry