com.google.common.base
Class Ascii

java.lang.Object
  extended by com.google.common.base.Ascii

@GwtCompatible
public final class Ascii
extends Object

Static methods pertaining to ASCII characters (those in the range of values 0x00 through 0x7F), and to strings containing such characters.

ASCII utilities also exist in other classes of this package:

Since:
7
Author:
Craig Berry, Gregory Kick

Field Summary
static byte ACK
          Acknowledge: A communication control character transmitted by a receiver as an affirmative response to a sender.
static byte BEL
          Bell ('\a'): A character for use when there is a need to call for human attention.
static byte BS
          Backspace ('\b'): A format effector which controls the movement of the printing position one printing space backward on the same printing line.
static byte CAN
          Cancel: A control character used to indicate that the data with which it is sent is in error or is to be disregarded.
static byte CR
          Carriage Return ('\r'): A format effector which controls the movement of the printing position to the first printing position on the same printing line.
static byte DC1
          Device Controls: Characters for the control of ancillary devices associated with data processing or telecommunication systems, more especially switching devices "on" or "off." (If a single "stop" control is required to interrupt or turn off ancillary devices, DC4 is the preferred assignment.)
static byte DC2
           
static byte DC3
           
static byte DC4
           
static byte DEL
          Delete: This character is used primarily to "erase" or "obliterate" erroneous or unwanted characters in perforated tape.
static byte DLE
          Data Link Escape: A communication control character which will change the meaning of a limited number of contiguously following characters.
static byte EM
          End of Medium: A control character associated with the sent data which may be used to identify the physical end of the medium, or the end of the used, or wanted, portion of information recorded on a medium.
static byte ENQ
          Enquiry: A communication control character used in data communication systems as a request for a response from a remote station.
static byte EOT
          End of Transmission: A communication control character used to indicate the conclusion of a transmission, which may have contained one or more texts and any associated headings.
static byte ESC
          Escape: A control character intended to provide code extension (supplementary characters) in general information interchange.
static byte ETB
          End of Transmission Block: A communication control character used to indicate the end of a block of data for communication purposes.
static byte ETX
          End of Text: A communication control character used to terminate a sequence of characters started with STX and transmitted as an entity.
static byte FF
          Form Feed ('\f'): A format effector which controls the movement of the printing position to the first pre-determined printing line on the next form or page.
static byte FS
          File/Group/Record/Unit Separator: These information separators may be used within data in optional fashion, except that their hierarchical relationship shall be: FS is the most inclusive, then GS, then RS, and US is least inclusive.
static byte GS
           
static byte HT
          Horizontal Tabulation ('\t'): A format effector which controls the movement of the printing position to the next in a series of predetermined positions along the printing line.
static byte LF
          Line Feed ('\n'): A format effector which controls the movement of the printing position to the next printing line.
static int MAX
          The maximum value of an ASCII character.
static int MIN
          The minimum value of an ASCII character.
static byte NAK
          Negative Acknowledge: A communication control character transmitted by a receiver as a negative response to the sender.
static byte NL
          Alternate name for LF.
static byte NUL
          Null ('\0'): The all-zeros character which may serve to accomplish time fill and media fill.
static byte RS
           
static byte SI
          Shift In: A control character indicating that the code combinations which follow shall be interpreted according to the standard code table.
static byte SO
          Shift Out: A control character indicating that the code combinations which follow shall be interpreted as outside of the character set of the standard code table until a Shift In character is reached.
static byte SOH
          Start of Heading: A communication control character used at the beginning of a sequence of characters which constitute a machine-sensible address or routing information.
static byte SP
          Space: A normally non-printing graphic character used to separate words.
static byte SPACE
          Alternate name for SP.
static byte STX
          Start of Text: A communication control character which precedes a sequence of characters that is to be treated as an entity and entirely transmitted through to the ultimate destination.
static byte SUB
          Substitute: A character that may be substituted for a character which is determined to be invalid or in error.
static byte SYN
          Synchronous Idle: A communication control character used by a synchronous transmission system in the absence of any other character to provide a signal from which synchronism may be achieved or retained.
static byte US
           
static byte VT
          Vertical Tabulation ('\v'): A format effector which controls the movement of the printing position to the next in a series of predetermined printing lines.
static byte XOFF
          Transmission off.
static byte XON
          Transmission on/off: Although originally defined as DC1, this ASCII control character is now better known as the XON code used for software flow control in serial communications.
 
Method Summary
static boolean isLowerCase(char c)
          Indicates whether c is one of the twenty-six lowercase ASCII alphabetic characters between 'a' and 'z' inclusive.
static boolean isUpperCase(char c)
          Indicates whether c is one of the twenty-six uppercase ASCII alphabetic characters between 'A' and 'Z' inclusive.
static char toLowerCase(char c)
          If the argument is an uppercase ASCII character returns the lowercase equivalent.
static String toLowerCase(String string)
          Returns a copy of the input string in which all uppercase ASCII characters have been converted to lowercase.
static char toUpperCase(char c)
          If the argument is a lowercase ASCII character returns the uppercase equivalent.
static String toUpperCase(String string)
          Returns a copy of the input string in which all lowercase ASCII characters have been converted to uppercase.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

NUL

public static final byte NUL
Null ('\0'): The all-zeros character which may serve to accomplish time fill and media fill. Normally used as a C string terminator.

Although RFC 20 names this as "Null", note that it is distinct from the C/C++ "NULL" pointer.

Since:
8
See Also:
Constant Field Values

SOH

public static final byte SOH
Start of Heading: A communication control character used at the beginning of a sequence of characters which constitute a machine-sensible address or routing information. Such a sequence is referred to as the "heading." An STX character has the effect of terminating a heading.

Since:
8
See Also:
Constant Field Values

STX

public static final byte STX
Start of Text: A communication control character which precedes a sequence of characters that is to be treated as an entity and entirely transmitted through to the ultimate destination. Such a sequence is referred to as "text." STX may be used to terminate a sequence of characters started by SOH.

Since:
8
See Also:
Constant Field Values

ETX

public static final byte ETX
End of Text: A communication control character used to terminate a sequence of characters started with STX and transmitted as an entity.

Since:
8
See Also:
Constant Field Values

EOT

public static final byte EOT
End of Transmission: A communication control character used to indicate the conclusion of a transmission, which may have contained one or more texts and any associated headings.

Since:
8
See Also:
Constant Field Values

ENQ

public static final byte ENQ
Enquiry: A communication control character used in data communication systems as a request for a response from a remote station. It may be used as a "Who Are You" (WRU) to obtain identification, or may be used to obtain station status, or both.

Since:
8
See Also:
Constant Field Values

ACK

public static final byte ACK
Acknowledge: A communication control character transmitted by a receiver as an affirmative response to a sender.

Since:
8
See Also:
Constant Field Values

BEL

public static final byte BEL
Bell ('\a'): A character for use when there is a need to call for human attention. It may control alarm or attention devices.

Since:
8
See Also:
Constant Field Values

BS

public static final byte BS
Backspace ('\b'): A format effector which controls the movement of the printing position one printing space backward on the same printing line. (Applicable also to display devices.)

Since:
8
See Also:
Constant Field Values

HT

public static final byte HT
Horizontal Tabulation ('\t'): A format effector which controls the movement of the printing position to the next in a series of predetermined positions along the printing line. (Applicable also to display devices and the skip function on punched cards.)

Since:
8
See Also:
Constant Field Values

LF

public static final byte LF
Line Feed ('\n'): A format effector which controls the movement of the printing position to the next printing line. (Applicable also to display devices.) Where appropriate, this character may have the meaning "New Line" (NL), a format effector which controls the movement of the printing point to the first printing position on the next printing line. Use of this convention requires agreement between sender and recipient of data.

Since:
8
See Also:
Constant Field Values

NL

public static final byte NL
Alternate name for LF. (LF is preferred.)

Since:
8
See Also:
Constant Field Values

VT

public static final byte VT
Vertical Tabulation ('\v'): A format effector which controls the movement of the printing position to the next in a series of predetermined printing lines. (Applicable also to display devices.)

Since:
8
See Also:
Constant Field Values

FF

public static final byte FF
Form Feed ('\f'): A format effector which controls the movement of the printing position to the first pre-determined printing line on the next form or page. (Applicable also to display devices.)

Since:
8
See Also:
Constant Field Values

CR

public static final byte CR
Carriage Return ('\r'): A format effector which controls the movement of the printing position to the first printing position on the same printing line. (Applicable also to display devices.)

Since:
8
See Also:
Constant Field Values

SO

public static final byte SO
Shift Out: A control character indicating that the code combinations which follow shall be interpreted as outside of the character set of the standard code table until a Shift In character is reached.

Since:
8
See Also:
Constant Field Values

SI

public static final byte SI
Shift In: A control character indicating that the code combinations which follow shall be interpreted according to the standard code table.

Since:
8
See Also:
Constant Field Values

DLE

public static final byte DLE
Data Link Escape: A communication control character which will change the meaning of a limited number of contiguously following characters. It is used exclusively to provide supplementary controls in data communication networks.

Since:
8
See Also:
Constant Field Values

DC1

public static final byte DC1
Device Controls: Characters for the control of ancillary devices associated with data processing or telecommunication systems, more especially switching devices "on" or "off." (If a single "stop" control is required to interrupt or turn off ancillary devices, DC4 is the preferred assignment.)

Since:
8
See Also:
Constant Field Values

XON

public static final byte XON
Transmission on/off: Although originally defined as DC1, this ASCII control character is now better known as the XON code used for software flow control in serial communications. The main use is restarting the transmission after the communication has been stopped by the XOFF control code.

Since:
8
See Also:
Constant Field Values

DC2

public static final byte DC2
Since:
8
See Also:
DC1, Constant Field Values

DC3

public static final byte DC3
Since:
8
See Also:
DC1, Constant Field Values

XOFF

public static final byte XOFF
Transmission off. @see #XON

Since:
8
See Also:
Constant Field Values

DC4

public static final byte DC4
Since:
8
See Also:
DC1, Constant Field Values

NAK

public static final byte NAK
Negative Acknowledge: A communication control character transmitted by a receiver as a negative response to the sender.

Since:
8
See Also:
Constant Field Values

SYN

public static final byte SYN
Synchronous Idle: A communication control character used by a synchronous transmission system in the absence of any other character to provide a signal from which synchronism may be achieved or retained.

Since:
8
See Also:
Constant Field Values

ETB

public static final byte ETB
End of Transmission Block: A communication control character used to indicate the end of a block of data for communication purposes. ETB is used for blocking data where the block structure is not necessarily related to the processing format.

Since:
8
See Also:
Constant Field Values

CAN

public static final byte CAN
Cancel: A control character used to indicate that the data with which it is sent is in error or is to be disregarded.

Since:
8
See Also:
Constant Field Values

EM

public static final byte EM
End of Medium: A control character associated with the sent data which may be used to identify the physical end of the medium, or the end of the used, or wanted, portion of information recorded on a medium. (The position of this character does not necessarily correspond to the physical end of the medium.)

Since:
8
See Also:
Constant Field Values

SUB

public static final byte SUB
Substitute: A character that may be substituted for a character which is determined to be invalid or in error.

Since:
8
See Also:
Constant Field Values

ESC

public static final byte ESC
Escape: A control character intended to provide code extension (supplementary characters) in general information interchange. The Escape character itself is a prefix affecting the interpretation of a limited number of contiguously following characters.

Since:
8
See Also:
Constant Field Values

FS

public static final byte FS
File/Group/Record/Unit Separator: These information separators may be used within data in optional fashion, except that their hierarchical relationship shall be: FS is the most inclusive, then GS, then RS, and US is least inclusive. (The content and length of a File, Group, Record, or Unit are not specified.)

Since:
8
See Also:
Constant Field Values

GS

public static final byte GS
Since:
8
See Also:
FS, Constant Field Values

RS

public static final byte RS
Since:
8
See Also:
FS, Constant Field Values

US

public static final byte US
Since:
8
See Also:
FS, Constant Field Values

SP

public static final byte SP
Space: A normally non-printing graphic character used to separate words. It is also a format effector which controls the movement of the printing position, one printing position forward. (Applicable also to display devices.)

Since:
8
See Also:
Constant Field Values

SPACE

public static final byte SPACE
Alternate name for SP.

Since:
8
See Also:
Constant Field Values

DEL

public static final byte DEL
Delete: This character is used primarily to "erase" or "obliterate" erroneous or unwanted characters in perforated tape.

Since:
8
See Also:
Constant Field Values

MIN

@Beta
public static final int MIN
The minimum value of an ASCII character.

Since:
9
See Also:
Constant Field Values

MAX

@Beta
public static final int MAX
The maximum value of an ASCII character.

Since:
9
See Also:
Constant Field Values
Method Detail

toLowerCase

public static String toLowerCase(String string)
Returns a copy of the input string in which all uppercase ASCII characters have been converted to lowercase. All other characters are copied without modification.


toLowerCase

public static char toLowerCase(char c)
If the argument is an uppercase ASCII character returns the lowercase equivalent. Otherwise returns the argument.


toUpperCase

public static String toUpperCase(String string)
Returns a copy of the input string in which all lowercase ASCII characters have been converted to uppercase. All other characters are copied without modification.


toUpperCase

public static char toUpperCase(char c)
If the argument is a lowercase ASCII character returns the uppercase equivalent. Otherwise returns the argument.


isLowerCase

public static boolean isLowerCase(char c)
Indicates whether c is one of the twenty-six lowercase ASCII alphabetic characters between 'a' and 'z' inclusive. All others (including non-ASCII characters) return false.


isUpperCase

public static boolean isUpperCase(char c)
Indicates whether c is one of the twenty-six uppercase ASCII alphabetic characters between 'A' and 'Z' inclusive. All others (including non-ASCII characters) return false.