(String, String)의 형태로 저장하는 단순화된 컬렉션클래스 Properties

Properties

HashMap의 구버전인 Hashtable을 상속받아 구현한것.

키와값을 (Object, Object)로 저장하는데 비해 Properties는 (String, String)의 형태로 저장하는 단순화된 컬렉션클래스.

주로 환경설정과 같은 속성 저장하는데 사용

https://standout.tistory.com/1377

HashTable 보다 새버전인 HashMap

 

 

 

 

Properties()
빈 Properties 객체를 생성합니다.

Properties properties = new Properties();

Properties(Properties defaults)
주어진 defaults를 가진 새로운 Properties 객체를 생성합니다.

Properties defaults = new Properties();
defaults.setProperty("defaultKey", "defaultValue");

Properties properties = new Properties(defaults);

String getProperty(String key)
주어진 키에 대한 값을 반환합니다.

Properties properties = new Properties();
properties.setProperty("key", "value");

String value = properties.getProperty("key");

String getProperty(String key, String defaultValue)
주어진 키에 대한 값을 반환하되, 해당 키가 존재하지 않을 경우 기본값을 반환합니다.

Properties properties = new Properties();
properties.setProperty("key", "value");

String value = properties.getProperty("nonExistingKey", "defaultValue");

void list(PrintStream out)
모든 속성을 출력합니다.

Properties properties = new Properties();
properties.setProperty("key1", "value1");
properties.setProperty("key2", "value2");

properties.list(System.out);

void list(PrintWriter out)
모든 속성을 출력합니다.

Properties properties = new Properties();
properties.setProperty("key1", "value1");
properties.setProperty("key2", "value2");

properties.list(new PrintWriter(System.out));

void load(InputStream inStream)
속성 목록을 InputStream으로부터 읽어들입니다.

Properties properties = new Properties();
try (InputStream inputStream = new FileInputStream("config.properties")) {
    properties.load(inputStream);
} catch (IOException e) {
    e.printStackTrace();
}

void load(Reader reader)
속성 목록을 Reader로부터 읽어들입니다.

Properties properties = new Properties();
try (Reader reader = new FileReader("config.properties")) {
    properties.load(reader);
} catch (IOException e) {
    e.printStackTrace();
}

void loadFromXML(InputStream in)
XML 속성 목록을 InputStream으로부터 읽어들입니다.

Properties properties = new Properties();
try (InputStream inputStream = new FileInputStream("config.xml")) {
    properties.loadFromXML(inputStream);
} catch (IOException e) {
    e.printStackTrace();
}

Enumeration peopertyNames()
속성 키의 열거형을 반환합니다.

Properties properties = new Properties();
Enumeration<?> enumeration = properties.propertyNames();

void save(OutputStream out, String header)
속성 목록을 OutputStream에 저장합니다.

Properties properties = new Properties();
try (OutputStream outputStream = new FileOutputStream("output.properties")) {
    properties.save(outputStream, "Header Comment");
} catch (IOException e) {
    e.printStackTrace();
}

Object setProperty(String key, String value)
지정된 키와 값으로 속성을 설정합니다.

Properties properties = new Properties();
properties.setProperty("key", "value");

void store(OutpurStream out, String comments)
속성 목록을 OutputStream에 저장합니다.

Properties properties = new Properties();
try (OutputStream outputStream = new FileOutputStream("output.properties")) {
    properties.store(outputStream, "Comments");
} catch (IOException e) {
    e.printStackTrace();
}

voi store(Writer writer, String comments)
속성 목록을 Writer에 저장합니다.

Properties properties = new Properties();
try (Writer writer = new FileWriter("output.properties")) {
    properties.store(writer, "Comments");
} catch (IOException e) {
    e.printStackTrace();
}

void storeToXML(OutputStream os, String comment)
XML 형식의 속성 목록을 OutputStream에 저장합니다.

Properties properties = new Properties();
try (OutputStream outputStream = new FileOutputStream("output.xml")) {
    properties.storeToXML(outputStream, "Comment");
} catch (IOException e) {
    e.printStackTrace();
}

void storeToXML(OutputStream os, String comment, String encoding)
XML 형식의 속성 목록을 OutputStream에 저장합니다.

Properties properties = new Properties();
try (OutputStream outputStream = new FileOutputStream("output.xml")) {
    properties.storeToXML(outputStream, "Comment", "UTF-8");
} catch (IOException e) {
    e.printStackTrace();
}

Set stringPropertyNames()
속성 키의 집합을 반환합니다.

Properties properties = new Properties();
Set<String> stringPropertyNames = properties.stringPropertyNames();