org.apache.tools.ant.util
public class LayoutPreservingProperties extends Properties
A Properties collection which preserves comments and whitespace present in the input stream from which it was loaded.
The class defers the usual work of the java.util.Properties class to there, but it also keeps track of the contents of the input stream from which it was loaded (if applicable), so that it can write out the properties in as close a form as possible to the input.
If no changes occur to property values, the output should be the same as the input, except for the leading date stamp, as normal for a properties file. Properties added are appended to the file. Properties whose values are changed are changed in place. Properties that are removed are excised. If theremoveComments
flag is set,
then the comments immediately preceding the property are also removed.
If a second set of properties is loaded into an existing set, the lines of the second set are added to the end. Note however, that if a property already stored is present in a stream subsequently loaded, then that property is removed before the new value is set. For example, consider the file
# the first line alpha=one # the second line beta=two
This file is loaded, and then the following is also loaded into the
same LayoutPreservingProperties
object
# association beta=band # and finally gamma=raysThe resulting collection sequence of logical lines depends on whether or not
removeComments
was set at the time the second stream
is loaded. If it is set, then the resulting list of lines is
# the first line alpha=one # association beta=band # and finally gamma=rays
If the flag is not set, then the comment "the second line" is retained,
although the key-value pair beta=two
is removed.
Constructor Summary | |
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LayoutPreservingProperties()
Create a new, empty, Properties collection, with no defaults. | |
LayoutPreservingProperties(Properties defaults)
Create a new, empty, Properties collection, with the specified defaults. |
Method Summary | |
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void | clear() |
Object | clone() |
boolean | isRemoveComments()
Returns true if comments are removed along with
properties, or false otherwise. |
void | listLines(PrintStream out)
Echo the lines of the properties (including blanks and comments) to the
stream. |
void | load(InputStream inStream) |
Object | put(Object key, Object value) |
Object | remove(Object key) |
void | saveAs(File dest)
Save the properties to a file. |
Object | setProperty(String key, String value) |
void | setRemoveComments(boolean val)
Sets the behaviour for comments accompanying properties that
are being removed. |
void | store(OutputStream out, String header) |
Parameters: defaults the default property values
true
if comments are removed along with
properties, or false
otherwise. If
true
, then when a property is removed, the comment
preceding it in the original file is removed also.Returns: true
if leading comments are removed when
a property is removed; false
otherwise
Parameters: out the stream to write to
Parameters: dest the file to write to
true
, then when a property
is removed, the comment preceding it in the original file is
removed also.Parameters: val true
if leading comments are to be
removed when a property is removed; false
otherwise