@Beta public final class CharStreams extends java.lang.Object
All method parameters must be non-null unless documented otherwise.
Some of the methods in this class take arguments with a generic type of
Readable & Closeable. A Reader implements both of
those interfaces. Similarly for Appendable & Closeable and
Writer.
| Modifier and Type | Method and Description |
|---|---|
static java.io.Writer |
asWriter(java.lang.Appendable target)
Returns a Writer that sends all output to the given
Appendable
target. |
static long |
copy(java.lang.Readable from,
java.lang.Appendable to)
Copies all characters between the
Readable and Appendable
objects. |
static java.io.Writer |
nullWriter()
Returns a
Writer that simply discards written chars. |
static java.util.List<java.lang.String> |
readLines(java.lang.Readable r)
Reads all of the lines from a
Readable object. |
static <T> T |
readLines(java.lang.Readable readable,
LineProcessor<T> processor)
Streams lines from a
Readable object, stopping when the processor
returns false or all lines have been read and returning the result
produced by the processor. |
static void |
skipFully(java.io.Reader reader,
long n)
Discards
n characters of data from the reader. |
static java.lang.String |
toString(java.lang.Readable r)
Reads all characters from a
Readable object into a String. |
public static long copy(java.lang.Readable from,
java.lang.Appendable to)
throws java.io.IOException
Readable and Appendable
objects. Does not close or flush either object.from - the object to read fromto - the object to write tojava.io.IOException - if an I/O error occurspublic static java.lang.String toString(java.lang.Readable r)
throws java.io.IOException
Readable object into a String.
Does not close the Readable.r - the object to read fromjava.io.IOException - if an I/O error occurspublic static java.util.List<java.lang.String> readLines(java.lang.Readable r)
throws java.io.IOException
Readable object. The lines do
not include line-termination characters, but do include other
leading and trailing whitespace.
Does not close the Readable. If reading files or resources you
should use the Files.readLines(java.io.File, java.nio.charset.Charset) and Resources.readLines(java.net.URL, java.nio.charset.Charset, com.google.common.io.LineProcessor<T>)
methods.
r - the object to read fromList containing all the linesjava.io.IOException - if an I/O error occurspublic static <T> T readLines(java.lang.Readable readable,
LineProcessor<T> processor)
throws java.io.IOException
Readable object, stopping when the processor
returns false or all lines have been read and returning the result
produced by the processor. Does not close readable. Note that this
method may not fully consume the contents of readable if the
processor stops processing early.java.io.IOException - if an I/O error occurspublic static void skipFully(java.io.Reader reader,
long n)
throws java.io.IOException
n characters of data from the reader. This method
will block until the full amount has been skipped. Does not close the
reader.reader - the reader to read fromn - the number of characters to skipjava.io.EOFException - if this stream reaches the end before skipping all
the charactersjava.io.IOException - if an I/O error occurspublic static java.io.Writer nullWriter()
Writer that simply discards written chars.public static java.io.Writer asWriter(java.lang.Appendable target)
Appendable
target. Closing the writer will close the target if it is Closeable, and flushing the writer will flush the target if it is Flushable.target - the object to which output will be sent