Class FileLinesCollection
- All Implemented Interfaces:
Iterable<MutableString>
,Collection<MutableString>
public class FileLinesCollection extends AbstractCollection<MutableString>
Collection
.
Warning: the lines returned by iterators generated by
instances of this class are not cacheable. The returned value is
a MutableString
instance that is reused
at each call, and that is modified by a call to hasNext()
.
Thus, for instance,
ObjectIterators.unwrap(fileLinesColletion.iterator());will not give the expected results. Use
allLines()
to get
the list of all lines (again, under the form of compact MutableString
s).
Note also that toString()
will return a single string containing all
file lines separated by the string associated with the system property line.separator
.
An instance of this class allows to access the lines of a file as a
Collection
. Using direct access is strongly discouraged (it will require a full scan of the file), but
the iterator()
can be fruitfully used to scan the file, and can be called any
number of times, as it opens an independent input stream at each call. For the
same reason, the returned iterator type (FileLinesCollection.FileLinesIterator
)
is Closeable
, and should be closed after usage.
Using a suitable constructor, it is possible
to specify that the file is compressed in gzip
format (in this case, it will be opened using a GZIPInputStream
).
Note that the first call to size()
will require a full file scan.
- Since:
- 0.9.2
- Author:
- Sebastiano Vigna
-
Nested Class Summary
Nested Classes Modifier and Type Class Description static class
FileLinesCollection.FileLinesIterator
An iterator over the lines of aFileLinesCollection
. -
Constructor Summary
Constructors Constructor Description FileLinesCollection(CharSequence filename, String encoding)
Creates a file-lines collection for the specified filename with the specified encoding.FileLinesCollection(CharSequence filename, String encoding, boolean zipped)
Creates a file-lines collection for the specified filename with the specified encoding, optionally assuming that the file is compressed usinggzip
format. -
Method Summary
Modifier and Type Method Description ObjectList<MutableString>
allLines()
Returns all lines of the file wrapped by this file-lines collection.FileLinesCollection.FileLinesIterator
iterator()
int
size()
Object[]
toArray()
<T> T[]
toArray(T[] a)
String
toString()
Methods inherited from class java.util.AbstractCollection
add, addAll, clear, contains, containsAll, isEmpty, remove, removeAll, retainAll
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
Methods inherited from interface java.util.Collection
equals, hashCode, parallelStream, removeIf, spliterator, stream, toArray
-
Constructor Details
-
FileLinesCollection
Creates a file-lines collection for the specified filename with the specified encoding.- Parameters:
filename
- a filename.encoding
- an encoding.
-
FileLinesCollection
Creates a file-lines collection for the specified filename with the specified encoding, optionally assuming that the file is compressed usinggzip
format.- Parameters:
filename
- a filename.encoding
- an encoding.zipped
- whetherfilename
is zipped.
-
-
Method Details
-
iterator
- Specified by:
iterator
in interfaceCollection<MutableString>
- Specified by:
iterator
in interfaceIterable<MutableString>
- Specified by:
iterator
in classAbstractCollection<MutableString>
-
size
public int size()- Specified by:
size
in interfaceCollection<MutableString>
- Specified by:
size
in classAbstractCollection<MutableString>
-
allLines
Returns all lines of the file wrapped by this file-lines collection.- Returns:
- all lines of the file wrapped by this file-lines collection.
-
toArray
- Specified by:
toArray
in interfaceCollection<MutableString>
- Overrides:
toArray
in classAbstractCollection<MutableString>
-
toArray
public <T> T[] toArray(T[] a)- Specified by:
toArray
in interfaceCollection<MutableString>
- Overrides:
toArray
in classAbstractCollection<MutableString>
-
toString
- Overrides:
toString
in classAbstractCollection<MutableString>
-