scriptella.expression
Class LineIterator

java.lang.Object
  scriptella.expression.LineIterator

All Implemented Interfaces:

java.io.Closeable, java.util.Iterator<java.lang.String>

public class LineIterator
extends java.lang.Object
implements java.util.Iterator<java.lang.String>, java.io.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

LineIterator(java.io.Reader reader)

LineIterator(java.io.Reader reader, PropertiesSubstitutor substitutor)

LineIterator(java.io.Reader reader, PropertiesSubstitutor substitutor, boolean trimLines)
Constructs iterator.

Method Summary

void	close()
protected java.lang.String	format(java.lang.String line) Applies additional formatting to the line read.
java.lang.String	getLineAt(int n) Returns specified line or null if EOF occured.
boolean	hasNext()
java.lang.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

Constructor Detail

LineIterator

public LineIterator(java.io.Reader reader)

LineIterator

public LineIterator(java.io.Reader reader,
                    PropertiesSubstitutor substitutor)

LineIterator

public LineIterator(java.io.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 Detail

hasNext

public boolean hasNext()
                throws RuntimeIOException

Specified by:

hasNext in interface java.util.Iterator<java.lang.String>

Returns:

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

Throws:

RuntimeIOException - if IO error occurs.

format

protected java.lang.String format(java.lang.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 java.lang.String next()
                      throws RuntimeIOException,
                             java.util.NoSuchElementException

Returns the next avalable line in a reader.

Specified by:

next in interface java.util.Iterator<java.lang.String>

Returns:

the next avalable line in a reader.

Throws:

RuntimeIOException - if IO error occurs.

java.util.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 java.lang.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 java.lang.UnsupportedOperationException

Specified by:

remove in interface java.util.Iterator<java.lang.String>

Throws:

java.lang.UnsupportedOperationException

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.io.Closeable

Throws:

java.io.IOException