Writer
abstract class Writer : Appendable, Closeable, Flushable
| kotlin.Any | |
| ↳ | java.io.Writer |
Abstract class for writing to character streams. The only methods that a subclass must implement are write(char[], int, int), flush(), and close(). Most subclasses, however, will override some of the methods defined here in order to provide higher efficiency, additional functionality, or both.
Summary
| Protected constructors | |
|---|---|
Writer()Creates a new character-stream writer whose critical sections will synchronize on the writer itself. |
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Creates a new character-stream writer whose critical sections will synchronize on the given object. |
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| Public methods | |
|---|---|
| open Writer |
Appends the specified character to this writer. |
| open Writer |
append(csq: CharSequence?)Appends the specified character sequence to this writer. |
| open Writer |
append(csq: CharSequence?, start: Int, end: Int)Appends a subsequence of the specified character sequence to this writer. |
| abstract Unit |
close()Closes the stream, flushing it first. |
| abstract Unit |
flush()Flushes the stream. |
| open static Writer! |
Returns a new |
| open Unit |
Writes an array of characters. |
| abstract Unit |
Writes a portion of an array of characters. |
| open Unit |
Writes a single character. |
| open Unit |
Writes a string. |
| open Unit |
Writes a portion of a string. |
| Properties | |
|---|---|
| Any! |
The object used to synchronize operations on this stream. |
Protected constructors
Writer
protected Writer()
Creates a new character-stream writer whose critical sections will synchronize on the writer itself.
Writer
protected Writer(lock: Any!)
Creates a new character-stream writer whose critical sections will synchronize on the given object.
| Parameters | |
|---|---|
lock |
Any!: Object to synchronize on |
Public methods
append
open fun append(c: Char): Writer
Appends the specified character to this writer.
An invocation of this method of the form out.append(c) behaves in exactly the same way as the invocation
out.write(c)
| Parameters | |
|---|---|
c |
Char: The 16-bit character to append |
| Return | |
|---|---|
Writer |
This writer |
| Exceptions | |
|---|---|
java.io.IOException |
If an I/O error occurs |
append
open fun append(csq: CharSequence?): Writer
Appends the specified character sequence to this writer.
An invocation of this method of the form out.append(csq) behaves in exactly the same way as the invocation
out.write(csq.toString())
Depending on the specification of toString for the character sequence csq, the entire sequence may not be appended. For instance, invoking the toString method of a character buffer will return a subsequence whose content depends upon the buffer's position and limit.
| Parameters | |
|---|---|
csq |
CharSequence?: The character sequence to append. If csq is null, then the four characters "null" are appended to this writer. |
| Return | |
|---|---|
Writer |
This writer |
| Exceptions | |
|---|---|
java.io.IOException |
If an I/O error occurs |
append
open fun append(
csq: CharSequence?,
start: Int,
end: Int
): Writer
Appends a subsequence of the specified character sequence to this writer. Appendable.
An invocation of this method of the form out.append(csq, start, end) when csq is not null behaves in exactly the same way as the invocation
<code>out.write(csq.subSequence(start, end).toString()) </code>
| Parameters | |
|---|---|
csq |
CharSequence?: The character sequence from which a subsequence will be appended. If csq is null, then characters will be appended as if csq contained the four characters "null". |
start |
Int: The index of the first character in the subsequence |
end |
Int: The index of the character following the last character in the subsequence |
| Return | |
|---|---|
Writer |
This writer |
| Exceptions | |
|---|---|
java.lang.IndexOutOfBoundsException |
If start or end are negative, start is greater than end, or end is greater than csq.length() |
java.io.IOException |
If an I/O error occurs |
close
abstract fun close(): Unit
Closes the stream, flushing it first. Once the stream has been closed, further write() or flush() invocations will cause an IOException to be thrown. Closing a previously closed stream has no effect.
| Exceptions | |
|---|---|
java.lang.Exception |
if this resource cannot be closed |
java.io.IOException |
If an I/O error occurs |
flush
abstract fun flush(): Unit
Flushes the stream. If the stream has saved any characters from the various write() methods in a buffer, write them immediately to their intended destination. Then, if that destination is another character or byte stream, flush it. Thus one flush() invocation will flush all the buffers in a chain of Writers and OutputStreams.
If the intended destination of this stream is an abstraction provided by the underlying operating system, for example a file, then flushing the stream guarantees only that bytes previously written to the stream are passed to the operating system for writing; it does not guarantee that they are actually written to a physical device such as a disk drive.
| Exceptions | |
|---|---|
java.io.IOException |
If an I/O error occurs |
nullWriter
open static fun nullWriter(): Writer!
Returns a new Writer which discards all characters. The returned stream is initially open. The stream is closed by calling the close() method. Subsequent calls to close() have no effect.
While the stream is open, the append(char), append(CharSequence), append(CharSequence, int, int), flush(), write(int), write(char[]), and write(char[], int, int) methods do nothing. After the stream has been closed, these methods all throw IOException.
The object used to synchronize operations on the returned Writer is not specified.
| Return | |
|---|---|
Writer! |
a Writer which discards all characters |
write
open fun write(cbuf: CharArray!): Unit
Writes an array of characters.
| Parameters | |
|---|---|
cbuf |
CharArray!: Array of characters to be written |
| Exceptions | |
|---|---|
java.io.IOException |
If an I/O error occurs |
write
abstract fun write(
cbuf: CharArray!,
off: Int,
len: Int
): Unit
Writes a portion of an array of characters.
| Parameters | |
|---|---|
cbuf |
CharArray!: Array of characters |
off |
Int: Offset from which to start writing characters |
len |
Int: Number of characters to write |
| Exceptions | |
|---|---|
java.lang.IndexOutOfBoundsException |
Implementations should throw this exception if off is negative, or len is negative, or off + len is negative or greater than the length of the given array |
java.io.IOException |
If an I/O error occurs |
write
open fun write(c: Int): Unit
Writes a single character. The character to be written is contained in the 16 low-order bits of the given integer value; the 16 high-order bits are ignored.
Subclasses that intend to support efficient single-character output should override this method.
| Parameters | |
|---|---|
c |
Int: int specifying a character to be written |
| Exceptions | |
|---|---|
java.io.IOException |
If an I/O error occurs |
write
open fun write(str: String!): Unit
Writes a string.
| Parameters | |
|---|---|
str |
String!: String to be written |
| Exceptions | |
|---|---|
java.io.IOException |
If an I/O error occurs |
write
open fun write(
str: String!,
off: Int,
len: Int
): Unit
Writes a portion of a string.
| Parameters | |
|---|---|
str |
String!: A String |
off |
Int: Offset from which to start writing characters |
len |
Int: Number of characters to write |
| Exceptions | |
|---|---|
java.lang.IndexOutOfBoundsException |
Implementations should throw this exception if off is negative, or len is negative, or off + len is negative or greater than the length of the given string |
java.io.IOException |
If an I/O error occurs |
Properties
lock
protected var lock: Any!
The object used to synchronize operations on this stream. For efficiency, a character-stream object may use an object other than itself to protect critical sections. A subclass should therefore use the object in this field rather than this or a synchronized method.