ByteParser (Starlink-UK API)

java.lang.Object
- nom.tam.util.ByteParser

```
public class ByteParser
extends Object
```
This class provides routines for efficient parsing of data stored in a byte array. This routine is optimized (in theory at least!) for efficiency rather than accuracy. The values read in for doubles or floats may differ in the last bit or so from the standard input utilities, especially in the case where a float is specified as a very long string of digits (substantially longer than the precision of the type).
The get methods generally are available with or without a length parameter specified. When a length parameter is specified only the bytes with the specified range from the current offset will be search for the number. If no length is specified, the entire buffer from the current offset will be searched.
The getString method returns a string with leading and trailing white space left intact. For all other get calls, leading white space is ignored. If fillFields is set, then the get methods check that only white space follows valid data and a FormatException is thrown if that is not the case. If fillFields is not set and valid data is found, then the methods return having read as much as possible. E.g., for the sequence "T123.258E13", a getBoolean, getInteger and getFloat call would return true, 123, and 2.58e12 when called in succession.

Constructor Summary

Constructors
Constructor and Description

ByteParser(byte[] input)
Construct a parser.

Constructors
Constructor and Description
`ByteParser(byte[] input)` Construct a parser.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`getBoolean()` Get a boolean value from the beginning of the buffer
`boolean`	`getBoolean(int length)` Get a boolean value from a specified region of the buffer
`byte[]`	`getBuffer()` Get the buffer being used by the parser
`double`	`getDouble()` Read in the buffer until a double is read.
`double`	`getDouble(int length)` Look for a double in the buffer.
`float`	`getFloat()` Get a floating point value from the buffer.
`float`	`getFloat(int length)` Get a floating point value in a region of the buffer
`int`	`getInt()` Look for an integer at the beginning of the buffer
`int`	`getInt(int length)` Convert a region of the buffer to an integer
`long`	`getLong(int length)` Look for a long in a specified region of the buffer
`int`	`getNumberLength()` Get the number of characters used to parse the previous number (or the length of the previous String returned).
`int`	`getOffset()` Get the current offset
`String`	`getString(int length)` Get a string
`boolean`	`isWhite(int length)` Is a region blank?
`void`	`setBuffer(byte[] buf)` Set the buffer for the parser
`void`	`setFillFields(boolean flag)` Do we require a field to completely fill up the specified length (with optional leading and trailing white space.
`void`	`setOffset(int offset)` Set the offset into the array.
`void`	`skip(int nBytes)` Skip bytes in the buffer
`int`	`skipWhite(int length)` Skip white space.

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

- Constructor Detail
  - ByteParser
```
public ByteParser(byte[] input)
```
    Construct a parser.
    
    Parameters:
    
    input - The byte array to be parsed. Note that the array can be re-used by refilling its contents and resetting the offset.
- Method Detail
  - setBuffer
```
public void setBuffer(byte[] buf)
```
    Set the buffer for the parser
  - getBuffer
```
public byte[] getBuffer()
```
    Get the buffer being used by the parser
  - setOffset
```
public void setOffset(int offset)
```
    Set the offset into the array.
    
    Parameters:
    
    offset - The desired offset from the beginning of the array.
  - setFillFields
```
public void setFillFields(boolean flag)
```
    Do we require a field to completely fill up the specified length (with optional leading and trailing white space.
    
    Parameters:
    
    flag - Is filling required?
  - getOffset
```
public int getOffset()
```
    Get the current offset
    
    Returns:
    
    The current offset within the buffer.
  - getNumberLength
```
public int getNumberLength()
```
    Get the number of characters used to parse the previous number (or the length of the previous String returned).
  - getDouble
```
public double getDouble()
                 throws FormatException
```
    Read in the buffer until a double is read. This will read the entire buffer if fillFields is set.
    
    Returns:
    
    The value found.
    
    Throws:
    
    FormatException
  - getDouble
```
public double getDouble(int length)
                 throws FormatException
```
    Look for a double in the buffer. Leading spaces are ignored.
    
    Parameters:
    
    length - The maximum number of characters used to parse this number. If fillFields is specified then exactly only whitespace may follow a valid double value.
    
    Throws:
    
    FormatException
  - getFloat
```
public float getFloat()
               throws FormatException
```
    Get a floating point value from the buffer. (see getDouble(int())
    
    Throws:
    
    FormatException
  - getFloat
```
public float getFloat(int length)
               throws FormatException
```
    Get a floating point value in a region of the buffer
    
    Throws:
    
    FormatException
  - getInt
```
public int getInt(int length)
           throws FormatException
```
    Convert a region of the buffer to an integer
    
    Throws:
    
    FormatException
  - getInt
```
public int getInt()
           throws FormatException
```
    Look for an integer at the beginning of the buffer
    
    Throws:
    
    FormatException
  - getLong
```
public long getLong(int length)
             throws FormatException
```
    Look for a long in a specified region of the buffer
    
    Throws:
    
    FormatException
  - getString
```
public String getString(int length)
```
    Get a string
    
    Parameters:
    
    length - The length of the string.
  - getBoolean
```
public boolean getBoolean()
                   throws FormatException
```
    Get a boolean value from the beginning of the buffer
    
    Throws:
    
    FormatException
  - getBoolean
```
public boolean getBoolean(int length)
                   throws FormatException
```
    Get a boolean value from a specified region of the buffer
    
    Throws:
    
    FormatException
  - skip
```
public void skip(int nBytes)
```
    Skip bytes in the buffer
  - skipWhite
```
public int skipWhite(int length)
```
    Skip white space. This routine skips with space in the input and returns the number of character skipped. White space is defined as ' ', '\t', '\n' or '\r'
    
    Parameters:
    
    length - The maximum number of characters to skip.
  - isWhite
```
public boolean isWhite(int length)
```
    Is a region blank?
    
    Parameters:
    
    length - The length of the region to be tested

Class ByteParser

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ByteParser

Method Detail

setBuffer

getBuffer

setOffset

setFillFields

getOffset

getNumberLength

getDouble

getDouble

getFloat

getFloat

getInt

getInt

getLong

getString

getBoolean

getBoolean

skip

skipWhite

isWhite