Package scriptella.expression

Class LineIterator

java.lang.Object

scriptella.expression.LineIterator

All Implemented Interfaces:

Closeable, AutoCloseable, Iterator<String>

Direct Known Subclasses:

TrackingLineIterator

public class LineIterator
extends Object
implements Iterator<String>, Closeable

An Iterator over the lines in a Reader, additionally properties substitution is performed.

This class change the contract of hasNext() method by throwing RuntimeIOException on IOException.

Decorators should override format(String) method.

This class is not threadsafe.

Version:

1.0

Author:

Fyodor Kupolov

See Also:

• PropertiesSubstitutor

Constructor Summary

Constructors

Constructor	Description
LineIterator(Reader reader)
LineIterator(Reader reader, PropertiesSubstitutor substitutor)
LineIterator(Reader reader, PropertiesSubstitutor substitutor, boolean trimLines)	Constructs iterator.

Method Summary

Modifier and Type	Method	Description
void	close()
protected String	format(String line)	Applies additional formatting to the line read.
String	getLineAt(int n)	Returns specified line or null if EOF occured.
boolean	hasNext()
String	next()	Returns the next avalable line in a reader.
void	remove()
int	skip(int n)	Skips N lines.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Iterator

forEachRemaining

Constructor Details

LineIterator

public LineIterator(Reader reader)

LineIterator

public LineIterator(Reader reader,
 PropertiesSubstitutor substitutor)

LineIterator

public LineIterator(Reader reader,
 PropertiesSubstitutor substitutor,
 boolean trimLines)

Constructs iterator.

Parameters:

reader - reader to iterate.

substitutor - substitutor to use to expand properties or null to disable substitution.

trimLines - true if the returned lines should be trimmed.

Method Details

hasNext

public boolean hasNext()
                throws RuntimeIOException

Specified by:

hasNext in interface Iterator<String>

Returns:

true if a line is available for reading by next()

Throws:

RuntimeIOException - if IO error occurs.

format

protected String format(String line)

Applies additional formatting to the line read.

May be overriden by decorators.

Parameters:

line - line of text, nulls allowed.

Returns:

formatted line.

next

public String next()
            throws RuntimeIOException,
NoSuchElementException

Returns the next avalable line in a reader.

Specified by:

next in interface Iterator<String>

Returns:

the next avalable line in a reader.

Throws:

RuntimeIOException - if IO error occurs.

NoSuchElementException - if has no more elements.

skip

public int skip(int n)

Skips N lines.

Parameters:

n - number of lines to skip.

Returns:

the actual number of lines skipped.

getLineAt

public String getLineAt(int n)

Returns specified line or null if EOF occured.

Parameters:

n - line number relative to the current line in the input. n>=0

Returns:

line n.

remove

public void remove()
            throws UnsupportedOperationException

Specified by:

remove in interface Iterator<String>

Throws:

UnsupportedOperationException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException