Packages This Package Prev Next Index
§3.6 Class Properties
public class java.util.Properties
extends java.util.Hashtable (I-§3.4)
{
// Fields
protected Properties defaults; §3.6.1
// Constructors
public Properties(); §3.6.2
public Properties(Properties defaults); §3.6.3
// Methods
public String getProperty(String key); §3.6.4
public String getProperty(String key, String defaultValue); §3.6.5
public void list(PrintStream out); §3.6.6
public void load(InputStream in); §3.6.7
public Enumeration propertyNames(); §3.6.8
public void save(OutputStream out, String header); §3.6.9
}
The Properties class represents a persistent set of properties. The Properties can be saved to a
stream or loaded from a stream. Each key and and its corresponding value in the property
list is a string.
A property list can contain another property list as its "defaults"; this second property list
is searched if the property key is not found in the original property list.
defaults
protected Properties defaults
- A property list which contains contains default values for any keys not
found in this property list.
Properties
public Properties()
- Creates an empty property list with no default values.
Properties
public Properties(Properties defaults)
- Creates an empty property list with the specified defaults.
- Parameters:
defaults
-
the defaults
getProperty
public String getProperty(String key)
- Searches for the property with the specified key in this property list.
- Parameters:
key
-
the property key
- Returns:
- the value in this property list with the specified key value. If the key is
not found in this property list, the default property list (I-§3.6.1), and
its defaults, recursively, are then checked. The method returns null if
the property is not found.
getProperty
public String getProperty(String key, String defaultValue)
- Searches for the property with the specified key in this property list.
- Parameters:
key
-
the hashtable key
defaultValue
-
a default value
- Returns:
- the value in this property list with the specified key value. If the key is
not found in this property list, the default property list (I-§3.6.1), and
its defaults, recursively, are then checked. The method returns the
default value argument if the property is not found.
list
public void list(PrintStream out)
- Prints this property list out to the specified output stream. This method is
useful for debugging.
- Parameters:
out
-
an output stream
load
public void load(InputStream in)
throws IOException
- Reads a property list from an input stream.
- Parameters:
in
-
the input stream
- Throws
- IOException (I-§2.29)
- If an error occurred when reading from the input stream.
propertyNames
public Enumeration propertyNames()
- Returns:
- An enumeration (I-§3.11) of all the keys in this property list, including the keys in the default property list (I-§3.6.1).
save
public void save(OutputStream out, String header)
- Stores this property list to the specified output stream. The string header is
printed as a comment at the beginning of the stream.
- Parameters:
out
-
an output stream
header
-
a description of the property list
Packages This Package Prev Next Index
Java API Document (HTML generated by dkramer on April 22, 1996)
Copyright © 1996 Sun Microsystems, Inc.
All rights reserved
Please send any comments or corrections to doug.kramer@sun.com