java.lang.Object
- org.openjdk.asmtools.jasm.ParseBase
- - org.openjdk.asmtools.jasm.Scanner

```
public class Scanner
extends ParseBase
```
A Scanner for Jasm tokens. Errors are reported to the environment object.
The scanner keeps track of the current token, the value of the current token (if any), and the start position of the current token.
The scan() method advances the scanner to the next token in the input.
The match() method is used to quickly match opening brackets (ie: '(', '{', or '[') with their closing counter part. This is useful during error recovery.
The compiler treats either "\n", "\r" or "\r\n" as the end of a line.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

protected static class Scanner.SyntaxError
SyntaxError is the generic error thrown for parsing problems.

Field Summary

Fields
Modifier and Type	Field	Description
`private char[]`	`buffer`
`protected int`	`ch`	The current character
`protected char`	`charValue`
`private int`	`count`
`protected java.lang.String`	`docComment`
`protected double`	`doubleValue`
`private java.util.function.Predicate<java.lang.Integer>`	`escapingAllowed`
`protected float`	`floatValue`
`protected java.lang.String`	`idValue`
`protected Environment`	`in`	Input stream
`protected boolean`	`inBits`
`protected int`	`intValue`
`protected long`	`longValue`
`private java.util.function.Predicate<java.lang.Integer>`	`noFunc`
`protected int`	`pos`	The position of the current token
`protected int`	`prevPos`	The position of the previous token
`protected int`	`radix`
`protected int`	`sign`
`protected java.lang.String`	`stringValue`
`protected JasmTokens.Token`	`token`	Current token
`private java.util.function.Predicate<java.lang.Integer>`	`yesAndProcessFunc`

Fields inherited from class org.openjdk.asmtools.jasm.ParseBase
debugFlag, env, parser, scanner

Constructor Summary

Constructors
Modifier Constructor Description

protected Scanner(Environment env)
main constructor.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`private java.lang.String`	`bufferString()`
`protected void`	`check(JasmTokens.Token t)`	Checks a token, throws an exception if not the same
`protected boolean`	`checkTokenIdent()`	Check the token may be identifier
`protected void`	`debugScan(java.lang.String dbstr)`
`protected void`	`expect(JasmTokens.Token t)`	Expects a token, scans the next token or throws an exception.
`static boolean`	`isUCDigit(int ch)`	Returns true if the character is a unicode digit.
`static boolean`	`isUCLetter(int ch)`	Returns true if the character is a Unicode letter.
`private void`	`putCh(int ch)`
`(package private) static java.lang.String`	`readableConstant(int t)`
`protected void`	`scan()`	scan Scan the next token.
`private void`	`scanCPRef()`	Scan a decimal at this point
`private java.lang.String`	`scanDocComment()`	Scan a doc comment.
`private int`	`scanEscapeChar()`	Scan an escape character.
`private void`	`scanIdentifier(char[] prefix)`	Scan an Identifier.
`protected void`	`scanModuleStatement()`
`private void`	`scanNumber()`	Scan a number.
`private void`	`scanReal()`	Scan a float.
`private void`	`scanString()`	Scan a string.
`private void`	`skipComment()`	Scan a comment.
`protected void`	`xscan()`

Methods inherited from class org.openjdk.asmtools.jasm.ParseBase
debugStr, enableDebug, init

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - in
```
protected Environment in
```
    Input stream
  - ch
```
protected int ch
```
    The current character
  - token
```
protected JasmTokens.Token token
```
    Current token
  - pos
```
protected int pos
```
    The position of the current token
  - charValue
```
protected char charValue
```
  - intValue
```
protected int intValue
```
  - longValue
```
protected long longValue
```
  - floatValue
```
protected float floatValue
```
  - doubleValue
```
protected double doubleValue
```
  - stringValue
```
protected java.lang.String stringValue
```
  - idValue
```
protected java.lang.String idValue
```
  - radix
```
protected int radix
```
  - docComment
```
protected java.lang.String docComment
```
  - count
```
private int count
```
  - buffer
```
private char[] buffer
```
  - escapingAllowed
```
private java.util.function.Predicate<java.lang.Integer> escapingAllowed
```
  - prevPos
```
protected int prevPos
```
    The position of the previous token
  - sign
```
protected int sign
```
  - inBits
```
protected boolean inBits
```
  - noFunc
```
private java.util.function.Predicate<java.lang.Integer> noFunc
```
  - yesAndProcessFunc
```
private java.util.function.Predicate<java.lang.Integer> yesAndProcessFunc
```
- Constructor Detail
  - Scanner
```
protected Scanner(Environment env)
           throws java.io.IOException
```
    main constructor. Create a scanner to scan an input stream.
    
    Throws:
    
    java.io.IOException
- Method Detail
  - scanModuleStatement
```
protected void scanModuleStatement()
                            throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - scan
```
protected void scan()
             throws java.io.IOException
```
    scan Scan the next token.
    
    Throws:
    
    java.io.IOException
  - checkTokenIdent
```
protected final boolean checkTokenIdent()
```
    Check the token may be identifier
  - readableConstant
```
static java.lang.String readableConstant(int t)
```
  - expect
```
protected final void expect(JasmTokens.Token t)
                     throws Scanner.SyntaxError,
                            java.io.IOException
```
    Expects a token, scans the next token or throws an exception.
    
    Throws:
    
    Scanner.SyntaxError
    
    java.io.IOException
  - check
```
protected final void check(JasmTokens.Token t)
                    throws Scanner.SyntaxError,
                           java.io.IOException
```
    Checks a token, throws an exception if not the same
    
    Throws:
    
    Scanner.SyntaxError
    
    java.io.IOException
  - putCh
```
private void putCh(int ch)
```
  - bufferString
```
private java.lang.String bufferString()
```
  - isUCDigit
```
public static boolean isUCDigit(int ch)
```
    Returns true if the character is a unicode digit.
    
    Parameters:
    
    ch - the character to be checked
  - isUCLetter
```
public static boolean isUCLetter(int ch)
```
    Returns true if the character is a Unicode letter.
    
    Parameters:
    
    ch - the character to be checked
  - skipComment
```
private void skipComment()
                  throws java.io.IOException
```
    Scan a comment. This method should be called once the initial /, * and the next character have been read.
    
    Throws:
    
    java.io.IOException
  - scanDocComment
```
private java.lang.String scanDocComment()
                                 throws java.io.IOException
```
    Scan a doc comment. This method should be called once the initial /, * and * have been read. It gathers the content of the comment (without leading spaces and '*'s) in the string buffer.
    
    Throws:
    
    java.io.IOException
  - scanCPRef
```
private void scanCPRef()
                throws java.io.IOException
```
    Scan a decimal at this point
    
    Throws:
    
    java.io.IOException
  - scanNumber
```
private void scanNumber()
                 throws java.io.IOException
```
    Scan a number. The first digit of the number should be the current character. We may be scanning hex, decimal, or octal at this point
    
    Throws:
    
    java.io.IOException
  - scanReal
```
private void scanReal()
               throws java.io.IOException
```
    Scan a float. We are either looking at the decimal, or we have already seen it and put it into the buffer. We haven't seen an exponent. Scan a float. Should be called with the current character is either the 'e', 'E' or '.'
    
    Throws:
    
    java.io.IOException
  - scanEscapeChar
```
private int scanEscapeChar()
                    throws java.io.IOException
```
    Scan an escape character.
    
    Returns:
    
    the character or '\\'
    
    Throws:
    
    java.io.IOException
  - scanString
```
private void scanString()
                 throws java.io.IOException
```
    Scan a string. The current character should be the opening " of the string.
    
    Throws:
    
    java.io.IOException
  - scanIdentifier
```
private void scanIdentifier(char[] prefix)
                     throws java.io.IOException
```
    Scan an Identifier. The current character should be the first character of the identifier.
    
    Throws:
    
    java.io.IOException
  - xscan
```
protected final void xscan()
                    throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - debugScan
```
protected void debugScan(java.lang.String dbstr)
```
    Overrides:
    
    debugScan in class ParseBase

Class Scanner

Nested Class Summary

Field Summary

Fields inherited from class org.openjdk.asmtools.jasm.ParseBase

Constructor Summary

Method Summary

Methods inherited from class org.openjdk.asmtools.jasm.ParseBase

Methods inherited from class java.lang.Object

Field Detail

in

ch

token

pos

charValue

intValue

longValue

floatValue

doubleValue

stringValue

idValue

radix

docComment

count

buffer

escapingAllowed

prevPos

sign

inBits

noFunc

yesAndProcessFunc

Constructor Detail

Scanner

Method Detail

scanModuleStatement

scan

checkTokenIdent

readableConstant

expect

check

putCh

bufferString

isUCDigit

isUCLetter

skipComment

scanDocComment

scanCPRef

scanNumber

scanReal

scanEscapeChar

scanString

scanIdentifier

xscan

debugScan