Properties JDK 1.6)

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publicsynchronized void clear () [Inherited From Hashtable]

Clears this hashtable so that it contains no keys.

publicsynchronized Object clone () [Inherited From Hashtable]

Creates a shallow copy of this hashtable.

publicsynchronized boolean contains (Object value) [Inherited From Hashtable]

Tests if some key maps into the specified value in this hashtable.

publicsynchronized boolean containsKey (Object key) [Inherited From Hashtable]

Tests if the specified object is a key in this hashtable.

Tests if the specified object is a key in this hashtable.
Returns: true if and only if the specified object is a key in this hashtable, as determined by the equals method; false otherwise.
Parameters:
- key - possible key
Throws:
- NullPointerException - if the key is null
See Also: Hashtable.contains(Object),

public boolean containsValue (Object value) [Inherited From Hashtable]

Returns true if this hashtable maps one or more keys to this value.

publicsynchronized Enumeration< V> elements () [Inherited From Hashtable] [Specified in Dictionary]

Returns an enumeration of the values in this hashtable.

public Set<Entry< K, V>> entrySet () [Inherited From Hashtable]

Returns a Set view of the mappings contained in this map.

publicsynchronized boolean equals (Object o) [Inherited From Hashtable]

Compares the specified Object with this Map for equality, as per the definition in the Map interface.

publicsynchronized V get (Object key) [Inherited From Hashtable] [Specified in Dictionary]

Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key.

More formally, if this map contains a mapping from a key k to a value v such that (key.equals(k)), then this method returns v; otherwise it returns null. (There can be at most one such mapping.)
Returns: the value to which the specified key is mapped, or {@code null} if this map contains no mapping for the key
Parameters:
- key - the key whose associated value is to be returned
Throws:
- NullPointerException - if the specified key is null
See Also: Hashtable.put(Object, Object),

public String getProperty (String key)

Searches for the property with the specified key in this property list.

Searches for the property with the specified key in this property list.
If the key is not found in this property list, the default property list,
and its defaults, recursively, are then checked. The method returns
null if the property is not found.
Returns: the value in this property list with the specified key value.
Parameters:
- key - the property key.
See Also: Properties.setProperty(java.lang.String, java.lang.String), Properties.defaults,

public String getProperty (String key, String defaultValue)

Searches for the property with the specified key in this property list.

publicsynchronized int hashCode () [Inherited From Hashtable]

Returns the hash code value for this Map as per the definition in the Map interface.

publicsynchronized boolean isEmpty () [Inherited From Hashtable] [Specified in Dictionary]

Tests if this hashtable maps no keys to values.

Tests if this hashtable maps no keys to values.
Returns: true if this hashtable maps no keys to values; false otherwise.

publicsynchronized Enumeration< K> keys () [Inherited From Hashtable] [Specified in Dictionary]

Returns an enumeration of the keys in this hashtable.

public Set< K> keySet () [Inherited From Hashtable]

Returns a Set view of the keys contained in this map.

public void list (PrintStream out)

Prints this property list out to the specified output stream.

public void list (PrintWriter out)

Prints this property list out to the specified output stream.

publicsynchronized void load (InputStream inStream) throws IOException

Reads a property list (key and element pairs) from the input byte stream.

publicsynchronized void load (Reader reader) throws IOException

Reads a property list (key and element pairs) from the input character stream in a simple line-oriented format.

Properties are processed in terms of lines. There are two kinds of line, natural lines and logical lines. A natural line is defined as a line of characters that is terminated either by a set of line terminator characters (\n or \r or \r\n) or by the end of the stream. A natural line may be either a blank line, a comment line, or hold all or some of a key-element pair. A logical line holds all the data of a key-element pair, which may be spread out across several adjacent natural lines by escaping the line terminator sequence with a backslash character \. Note that a comment line cannot be extended in this manner; every natural line that is a comment must have its own comment indicator, as described below. Lines are read from input until the end of the stream is reached.

A natural line that contains only white space characters is considered blank and is ignored. A comment line has an ASCII '#' or '!' as its first non-white space character; comment lines are also ignored and do not encode key-element information. In addition to line terminators, this format considers the characters space (' ', '\u0020'), tab ('\t', '\u0009'), and form feed ('\f', '\u000C') to be white space.

If a logical line is spread across several natural lines, the backslash escaping the line terminator sequence, the line terminator sequence, and any white space at the start of the following line have no affect on the key or element values. The remainder of the discussion of key and element parsing (when loading) will assume all the characters constituting the key and element appear on a single natural line after line continuation characters have been removed. Note that it is not sufficient to only examine the character preceding a line terminator sequence to decide if the line terminator is escaped; there must be an odd number of contiguous backslashes for the line terminator to be escaped. Since the input is processed from left to right, a non-zero even number of 2n contiguous backslashes before a line terminator (or elsewhere) encodes n backslashes after escape processing.

The key contains all of the characters in the line starting with the first non-white space character and up to, but not including, the first unescaped '=', ':', or white space character other than a line terminator. All of these key termination characters may be included in the key by escaping them with a preceding backslash character; for example,

\:\=

would be the two-character key ":=". Line terminator characters can be included using \r and \n escape sequences. Any white space after the key is skipped; if the first non-white space character after the key is '=' or ':', then it is ignored and any white space characters after it are also skipped. All remaining characters on the line become part of the associated element string; if there are no remaining characters, the element is the empty string "". Once the raw character sequences constituting the key and element are identified, escape processing is performed as described above.

As an example, each of the following three lines specifies the key "Truth" and the associated element value "Beauty":

 Truth = Beauty
        Truth:Beauty
 Truth                  :Beauty

As another example, the following three lines specify a single property:

 fruits                           apple, banana, pear, \
                                  cantaloupe, watermelon, \
                                  kiwi, mango

The key is "fruits" and the associated element is:

"apple, banana, pear, cantaloupe, watermelon, kiwi, mango"

Note that a space appears before each \ so that a space will appear after each comma in the final result; the \, line terminator, and leading white space on the continuation line are merely discarded and are not replaced by one or more other characters.

As a third example, the line:

cheeses

specifies that the key is "cheeses" and the associated element is the empty string "".

Characters in keys and elements can be represented in escape sequences similar to those used for character and string literals (see §3.3 and §3.10.6 of the Java Language Specification). The differences from the character escape sequences and Unicode escapes used for characters and strings are:

Octal escapes are not recognized.
The character sequence \b does not represent a backspace character.
The method does not treat a backslash character, \, before a non-valid escape character as an error; the backslash is silently dropped. For example, in a Java string the sequence "\z" would cause a compile time error. In contrast, this method silently drops the backslash. Therefore, this method treats the two character sequence "\b" as equivalent to the single character 'b'.
Escapes are not necessary for single and double quotes; however, by the rule above, single and double quote characters preceded by a backslash still yield single and double quote characters, respectively.
Only a single 'u' character is allowed in a Uniocde escape sequence.

The specified stream remains open after this method returns.
Parameters:
- reader - the input character stream.
Throws:
- IOException - if an error occurred when reading from the input stream.
- IllegalArgumentException - if a malformed Unicode escape appears in the input.
Since: 1.6

publicsynchronized void loadFromXML (InputStream in) throws IOException InvalidPropertiesFormatException

Loads all of the properties represented by the XML document on the specified input stream into this properties table.

The XML document must have the following DOCTYPE declaration:

 <!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd">

Furthermore, the document must satisfy the properties DTD described above.

The specified stream is closed after this method returns.
Parameters:
- in - the input stream from which to read the XML document.
Throws:
- IOException - if reading from the specified input stream results in an IOException.
- InvalidPropertiesFormatException - Data on input stream does not constitute a valid XML document with the mandated document type.
- NullPointerException - if in is null.
Since: 1.5
See Also: Properties.storeToXML(OutputStream, String, String),

public Enumeration<Object> propertyNames ()

Returns an enumeration of all the keys in this property list, including distinct keys in the default property list if a key of the same name has not already been found from the main properties list.

publicsynchronized V put ( K key, V value) [Inherited From Hashtable] [Specified in Dictionary]

Maps the specified key to the specified value in this hashtable.

Maps the specified key to the specified value in this hashtable. Neither the key nor the value can be null.

The value can be retrieved by calling the get method with a key that is equal to the original key.
Returns: the previous value of the specified key in this hashtable, or null if it did not have one
Parameters:
- key - the hashtable key
- value - the value
Throws:
- NullPointerException - if the key or value is null
See Also: Object.equals(Object), Hashtable.get(Object),

publicsynchronized void putAll (Map<Object, Object> t) [Inherited From Hashtable]

Copies all of the mappings from the specified map to this hashtable.

protected void rehash () [Inherited From Hashtable]

Increases the capacity of and internally reorganizes this hashtable, in order to accommodate and access its entries more efficiently.

publicsynchronized V remove (Object key) [Inherited From Hashtable] [Specified in Dictionary]

Removes the key (and its corresponding value) from this hashtable.

Removes the key (and its corresponding value) from this
hashtable. This method does nothing if the key is not in the hashtable.
Returns: the value to which the key had been mapped in this hashtable, or null if the key did not have a mapping
Parameters:
- key - the key that needs to be removed
Throws:
- NullPointerException - if the key is null

@Deprecated

publicsynchronized void ~~save~~ (OutputStream out, String comments)

Calls the store(OutputStream out, String comments) method and suppresses IOExceptions that were thrown.

Calls the store(OutputStream out, String comments) method
and suppresses IOExceptions that were thrown.
Parameters:
- out - an output stream.
- comments - a description of the property list.
Throws:
- ClassCastException - if this Properties object contains any keys or values that are not Strings.

publicsynchronized Object setProperty (String key, String value)

Calls the Hashtable method put.

Calls the Hashtable method put. Provided for
parallelism with the getProperty method. Enforces use of
strings for property keys and values. The value returned is the
result of the Hashtable call to put.
Returns: the previous value of the specified key in this property list, or null if it did not have one.
Parameters:
- key - the key to be placed into this property list.
- value - the value corresponding to key.
Since: 1.2
See Also: Properties.getProperty(java.lang.String),

publicsynchronized int size () [Inherited From Hashtable] [Specified in Dictionary]

Returns the number of keys in this hashtable.

public void store (OutputStream out, String comments) throws IOException

Writes this property list (key and element pairs) in this Properties table to the output stream in a format suitable for loading into a Properties table using the load(InputStream) method.

Properties from the defaults table of this Properties table (if any) are not written out by this method.

This method outputs the comments, properties keys and values in the same format as specified in store(Writer), with the following differences:

The stream is written using the ISO 8859-1 character encoding.
Characters not in Latin-1 in the comments are written as \uxxxx for their appropriate unicode hexadecimal value xxxx.
Characters less than \u0020 and characters greater than \u007E in property keys or values are written as \uxxxx for the appropriate hexadecimal value xxxx.

After the entries have been written, the output stream is flushed. The output stream remains open after this method returns.

Parameters:
- out - an output stream.
- comments - a description of the property list.
Throws:
- IOException - if writing this property list to the specified output stream throws an IOException.
- ClassCastException - if this Properties object contains any keys or values that are not Strings.
- NullPointerException - if out is null.
Since: 1.2

public void store (Writer writer, String comments) throws IOException

Writes this property list (key and element pairs) in this Properties table to the output character stream in a format suitable for using the load(Reader) method.

Properties from the defaults table of this Properties table (if any) are not written out by this method.

If the comments argument is not null, then an ASCII # character, the comments string, and a line separator are first written to the output stream. Thus, the comments can serve as an identifying comment. Any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a line feed in comments is replaced by a line separator generated by the Writer and if the next character in comments is not character # or character ! then an ASCII # is written out after that line separator.

Next, a comment line is always written, consisting of an ASCII # character, the current date and time (as if produced by the toString method of Date for the current time), and a line separator as generated by the Writer.

Then every entry in this Properties table is written out, one per line. For each entry the key string is written, then an ASCII =, then the associated element string. For the key, all space characters are written with a preceding \ character. For the element, leading space characters, but not embedded or trailing space characters, are written with a preceding \ character. The key and element characters #, !, =, and : are written with a preceding backslash to ensure that they are properly loaded.

After the entries have been written, the output stream is flushed. The output stream remains open after this method returns.

Parameters:
- writer - an output character stream writer.
- comments - a description of the property list.
Throws:
- IOException - if writing this property list to the specified output stream throws an IOException.
- ClassCastException - if this Properties object contains any keys or values that are not Strings.
- NullPointerException - if writer is null.
Since: 1.6

publicsynchronized void storeToXML (OutputStream os, String comment) throws IOException

Emits an XML document representing all of the properties contained in this table.

publicsynchronized void storeToXML (OutputStream os, String comment, String encoding) throws IOException

Emits an XML document representing all of the properties contained in this table, using the specified encoding.

The XML document will have the following DOCTYPE declaration:

 <!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd">

If the specified comment is null then no comment will be stored in the document.

The specified stream remains open after this method returns.
Parameters:
- os - the output stream on which to emit the XML document.
- comment - a description of the property list, or null if no comment is desired.
Throws:
- IOException - if writing to the specified output stream results in an IOException.
- NullPointerException - if os is null, or if encoding is null.
- ClassCastException - if this Properties object contains any keys or values that are not Strings.
Since: 1.5
See Also: Properties.loadFromXML(InputStream),

public Set<String> stringPropertyNames ()

Returns a set of keys in this property list where the key and its corresponding value are strings, including distinct keys in the default property list if a key of the same name has not already been found from the main properties list.

publicsynchronized String toString () [Inherited From Hashtable]

Returns a string representation of this Hashtable object in the form of a set of entries, enclosed in braces and separated by the ASCII characters ", " (comma and space).

public Collection< V> values () [Inherited From Hashtable]

Returns a Collection view of the values contained in this map.