dw.io
Class Reader
dw.io.Reader
The class supports reading characters from a stream.
All Known Subclasses
Properties
lines
:
List
(Read Only)
The method reads the whole input stream, parses it and returns a list of strings.
Using this method on large feeds is inherently unsafe and may lead to an out-of-memory condition. Instead use
method readLine() and process one line at a time.
Deprecated:
Use readLines()
string
:
String
(Read Only)
The method reads the whole input stream as one string and returns it.
Using this method is unsafe if the length of the input stream is not known and may lead to an out-of-memory
condition. Instead use method readN(Number).
Deprecated:
Use readString()
Constructor Summary
Reader(stream
:
InputStream)
Create a reader from a stream using UTF-8 character encoding.
Reader(stream
:
InputStream, encoding
:
String)
Create a reader from a stream using the specified character encoding.
Method Summary
close()
:
void
Closes the reader.
readLines()
:
List
The method reads the whole input stream, parses it and returns a list of strings.
readString()
:
String
The method reads the whole input stream as one string and returns it.
ready()
:
boolean
Identifies if this stream is ready to be read.
Methods inherited from class
Object
assign, create, create, defineProperties, defineProperty, entries, freeze, fromEntries, getOwnPropertyDescriptor, getOwnPropertyNames, getOwnPropertySymbols, getPrototypeOf, hasOwnProperty, is, isExtensible, isFrozen, isPrototypeOf, isSealed, keys, preventExtensions, propertyIsEnumerable, seal, setPrototypeOf, toLocaleString, toString, valueOf, values
Constructor Detail
Reader
public Reader(source
:
String)
Creates a reader from a string.
Parameters:
source
-
the source string.
Reader
public Reader(stream
:
InputStream)
Create a reader from a stream using UTF-8 character encoding.
Parameters:
stream
-
the input stream to use.
Method Detail
getLines
getLines()
:
List
The method reads the whole input stream, parses it and returns a list of strings.
Using this method on large feeds is inherently unsafe and may lead to an out-of-memory condition. Instead use
method readLine() and process one line at a time.
Deprecated:
Use readLines()
Returns:
a list of strings
getString
getString()
:
String
The method reads the whole input stream as one string and returns it.
Using this method is unsafe if the length of the input stream is not known and may lead to an out-of-memory
condition. Instead use method readN(Number).
Deprecated:
Use readString()
Returns:
a string, which represents the whole content of the InputStream
Throws:
IOException
-
if something went wrong while reading from the underlying stream
read
read()
:
String
Reads a single character from the stream. The method returns null if the end of the stream is reached.
Returns:
a single character in a string, or null if the end of the stream is reached
read
Reads multiple characters from the stream as string. The actual number of characters that were read can be
determined from the length of the returned string. If the end of the stream is reached and no more characters can
be read, the method exits with an exception.
Deprecated:
use readN(Number) instead which does not throw an exception if the stream is exhausted
Parameters:
length
-
the number of characters to read.
Returns:
a string whose length is controlled by the length parameter. The actual number of characters that were read can be determined from the length of the returned string.
Throws:
an
-
exception if the stream is exhausted
readLine
readLine()
:
String
Reads the next line.
Returns:
A String containing the contents of the line, not including any line termination characters, or null if the end of the stream has been reached.
readLines
readLines()
:
List
The method reads the whole input stream, parses it and returns a list of strings.
Using this method on large feeds is inherently unsafe and may lead to an out-of-memory condition. Instead use
method readLine() and process one line at a time.
Returns:
a list of strings
readN
Reads n characters from the stream as string. The actual number of characters that were read can be determined
from the length of the returned string. If the end of the stream is reached and no more characters can be read,
the method returns null.
Parameters:
n
-
the number of characters to read
Returns:
a string whose maximum length is controlled by the n parameter, or null if the end of the stream is reached and no more characters can be read
readString
readString()
:
String
The method reads the whole input stream as one string and returns it.
Using this method is unsafe if the length of the input stream is not known and may lead to an out-of-memory
condition. Instead use method readN(Number).
Returns:
a string, which represents the whole content of the InputStream
Throws:
IOException
-
if something went wrong while reading from the underlying stream
ready
ready()
:
boolean
Identifies if this stream is ready to be read.
Returns:
true guarantees that the stream is ready to read without waiting for input. A false response means that the stream may or may not block to wait for input. Note that returning false does not guarantee that the next read() will block.
skip
skip(n
:
Number)
:
void
Skips the specified number of characters in the stream.
Parameters:
n
-
the number of characters to skip.