Jython 2.7.4 · org.python.modules._io.OpenMode · APIdia, the JavaDoc alternative

Field Summary

Modifier and Type	Field and Description
public boolean	appending Whether this file is opened in appending mode ('a')
public boolean	binary Whether this file is opened in binary mode ('b')
public boolean	invalid Set true when any invalid symbol or combination is discovered
public String	message Error message describing the way in which the mode is invalid, or null if no problem has been found.
public final String	originalModeString Original string supplied as the mode
public boolean	other Whether the mode contained some other symbol from the allowed ones
public boolean	reading Whether this file is opened for reading ('r')
public boolean	text Whether this file is opened in text mode ('t')
public boolean	universal Whether this file is opened in universal newlines mode ('U')
public boolean	updating Whether this file is opened for updating ('+')
public boolean	writing Whether this file is opened for writing ('w')

Constructor Summary

Access	Constructor and Description
public	OpenMode(String mode) Decode the given string to an OpenMode object, checking for duplicate or unrecognised mode letters.

Method Summary

Modifier and Type	Method and Description
public void	checkValid() Call `validate()` and raise an exception if the mode string is not valid, as signalled by either `invalid` or `other` being `true` after that call.
public String	Returns: "r", "w", or "a" with optional "+". forFileIO() The mode string we need when constructing a `FileIO` initialised with the present mode.
public String	Returns: "", or "U". text() The mode string that a text file should claim to have, when initialised with the present mode.
public String	toString() Overrides java.lang.Object.toString. Returns a string representation of the object.
public void	validate() Adjust and validate the flags decoded from the mode string.
public void	validate(String argument to `open()` encoding, String argument to `open()` errors, String argument to `open()` newline) Perform additional validation of the flags relevant to text files.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll wait wait wait

Field Detail

appending	back to summary
public boolean appending Whether this file is opened in appending mode ('a')

binary	back to summary
public boolean binary Whether this file is opened in binary mode ('b')

invalid	back to summary
public boolean invalid Set true when any invalid symbol or combination is discovered

message	back to summary
public String message Error message describing the way in which the mode is invalid, or null if no problem has been found. This field may be set by the constructor (in the case of duplicate or unrecognised mode letters), by the `validate()` method, or by client code.

originalModeString	back to summary
public final String originalModeString Original string supplied as the mode

other	back to summary
public boolean other Whether the mode contained some other symbol from the allowed ones

reading	back to summary
public boolean reading Whether this file is opened for reading ('r')

text	back to summary
public boolean text Whether this file is opened in text mode ('t')

universal	back to summary
public boolean universal Whether this file is opened in universal newlines mode ('U')

updating	back to summary
public boolean updating Whether this file is opened for updating ('+')

writing	back to summary
public boolean writing Whether this file is opened for writing ('w')

Constructor Detail

OpenMode	back to summary
public OpenMode(String mode) Decode the given string to an OpenMode object, checking for duplicate or unrecognised mode letters. Valid letters are those in "rwa+btU". Errors in the mode string do not raise an exception, they simply generate an appropriate error message in `message`. After construction, a client should always call `validate()` to complete validity checks.

Method Detail

checkValid back to summary

checkValid	back to summary
public void checkValid() throws PyException Call `validate()` and raise an exception if the mode string is not valid, as signalled by either `invalid` or `other` being `true` after that call. If no more specific message has been assigned in `message`, report the original mode string. Exceptions PyException: `ValueError` if the mode string was invalid.

public void checkValid() throws PyException

Call validate() and raise an exception if the mode string is not valid, as signalled by either invalid or other being true after that call. If no more specific message has been assigned in message, report the original mode string.

Exceptions

PyException:: ValueError if the mode string was invalid.

forFileIO back to summary

forFileIO	back to summary
public String forFileIO() The mode string we need when constructing a `FileIO` initialised with the present mode. Note that this is not the same as the full open mode because it omits the text-based attributes. Returns:String "r", "w", or "a" with optional "+".

public String forFileIO()

The mode string we need when constructing a FileIO initialised with the present mode. Note that this is not the same as the full open mode because it omits the text-based attributes.

Returns:String: "r", "w", or "a" with optional "+".

text	back to summary
public String text() The mode string that a text file should claim to have, when initialised with the present mode. Note that this only contains text-based attributes. Since mode 't' has no effect, except to produce an error if specified with 'b', we don't reproduce it. Returns:String "", or "U".

text

back to summary

public String text()

The mode string that a text file should claim to have, when initialised with the present mode. Note that this only contains text-based attributes. Since mode 't' has no effect, except to produce an error if specified with 'b', we don't reproduce it.

Returns:String: "", or "U".

toString back to summary

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Doc from java.lang.Object.toString. Returns a string representation of the object. Satisfying this method's contract implies a non-`null` result must be returned. Returns:String a string representation of the object Annotations @Override

public String toString()

Overrides java.lang.Object.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object. Satisfying this method's contract implies a non-null result must be returned.

Returns:String

a string representation of the object

Annotations

@Override

validate back to summary

validate	back to summary
public void validate() Adjust and validate the flags decoded from the mode string. The method affects the flags where the presence of one flag implies another, then if the `invalid` flag is not already `true`, it checks the validity of the flags against combinations allowed by the Python `io.open()` function. In the case of a violation, it sets the `invalid` flag, and sets `message` to a descriptive message. The point of the qualification "if the `invalid` flag is not already `true`" is that the message should always describe the first problem discovered. If left blank, as in fact the constructor does, it will be filled by the generic message when `checkValid()` is finally called. Clients may override this method (by sub-classing) to express the validation correct in their context. The invalid combinations enforced here are those for the "raw" (ie non-text) file types: `universal & (writing \| appending)`, `text & binary`, `reading & writing`, `appending & (reading \| writing)` See also `validate(String, String, String)` for additional checks relevant to text files.

public void validate()

Adjust and validate the flags decoded from the mode string. The method affects the flags where the presence of one flag implies another, then if the invalid flag is not already true, it checks the validity of the flags against combinations allowed by the Python io.open() function. In the case of a violation, it sets the invalid flag, and sets message to a descriptive message. The point of the qualification "if the invalid flag is not already true" is that the message should always describe the first problem discovered. If left blank, as in fact the constructor does, it will be filled by the generic message when checkValid() is finally called. Clients may override this method (by sub-classing) to express the validation correct in their context.

The invalid combinations enforced here are those for the "raw" (ie non-text) file types:

universal & (writing | appending),
text & binary,
reading & writing,
appending & (reading | writing)

See also validate(String, String, String) for additional checks relevant to text files.

validate back to summary

validate	back to summary
public void validate(String encoding, String errors, String newline) Perform additional validation of the flags relevant to text files. If `invalid` is not already `true`, and the mode includes `binary`, then all the arguments to this call must be `null`. If the criterion is not met, then on return from the method, `invalid==true` and `message` is set to a standard error message. This is the standard additional validation applicable to text files. (By "standard" we mean the test and messages that CPython `io.open` uses.) Parameters encoding:String argument to `open()` errors:String argument to `open()` newline:String argument to `open()`

public void validate(String encoding, String errors, String newline)

Perform additional validation of the flags relevant to text files. If invalid is not already true, and the mode includes binary, then all the arguments to this call must be null. If the criterion is not met, then on return from the method, invalid==true and message is set to a standard error message. This is the standard additional validation applicable to text files. (By "standard" we mean the test and messages that CPython io.open uses.)

Parameters