public class LayoutPreservingProperties
extends java.util.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 and Description |
---|
LayoutPreservingProperties()
Create a new, empty, Properties collection, with no defaults.
|
LayoutPreservingProperties(java.util.Properties defaults)
Create a new, empty, Properties collection, with the specified defaults.
|
Modifier and Type | Method and Description |
---|---|
void |
clear() |
java.lang.Object |
clone() |
boolean |
isRemoveComments()
Returns
true if comments are removed along with
properties, or false otherwise. |
void |
listLines(java.io.PrintStream out)
Echo the lines of the properties (including blanks and comments) to the
stream.
|
void |
load(java.io.InputStream inStream) |
java.lang.Object |
put(java.lang.Object key,
java.lang.Object value) |
java.lang.Object |
remove(java.lang.Object key) |
void |
saveAs(java.io.File dest)
Save the properties to a file.
|
java.lang.Object |
setProperty(java.lang.String key,
java.lang.String value) |
void |
setRemoveComments(boolean val)
Sets the behaviour for comments accompanying properties that
are being removed.
|
void |
store(java.io.OutputStream out,
java.lang.String header) |
getProperty, getProperty, list, list, load, loadFromXML, propertyNames, save, store, storeToXML, storeToXML, stringPropertyNames
public LayoutPreservingProperties()
public LayoutPreservingProperties(java.util.Properties defaults)
defaults
- the default property valuespublic boolean isRemoveComments()
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.true
if leading comments are removed when
a property is removed; false
otherwisepublic void setRemoveComments(boolean val)
true
, then when a property
is removed, the comment preceding it in the original file is
removed also.val
- true
if leading comments are to be
removed when a property is removed; false
otherwisepublic void load(java.io.InputStream inStream) throws java.io.IOException
load
in class java.util.Properties
java.io.IOException
public java.lang.Object put(java.lang.Object key, java.lang.Object value) throws java.lang.NullPointerException
put
in interface java.util.Map<java.lang.Object,java.lang.Object>
put
in class java.util.Hashtable<java.lang.Object,java.lang.Object>
java.lang.NullPointerException
public java.lang.Object setProperty(java.lang.String key, java.lang.String value) throws java.lang.NullPointerException
setProperty
in class java.util.Properties
java.lang.NullPointerException
public void clear()
clear
in interface java.util.Map<java.lang.Object,java.lang.Object>
clear
in class java.util.Hashtable<java.lang.Object,java.lang.Object>
public java.lang.Object remove(java.lang.Object key)
remove
in interface java.util.Map<java.lang.Object,java.lang.Object>
remove
in class java.util.Hashtable<java.lang.Object,java.lang.Object>
public java.lang.Object clone()
clone
in class java.util.Hashtable<java.lang.Object,java.lang.Object>
public void listLines(java.io.PrintStream out)
out
- the stream to write topublic void saveAs(java.io.File dest) throws java.io.IOException
dest
- the file to write tojava.io.IOException
public void store(java.io.OutputStream out, java.lang.String header) throws java.io.IOException
store
in class java.util.Properties
java.io.IOException