How to use

getProperty

method

in

java.lang.System

 public class JavaApplication1 {
 public static void main(String[] args) {
    System.out.println("Working Directory = " +
       System.getProperty("user.dir"));
 }
}

/**
 * Get the <em>profile value</em> indicated by the specified key from the
 * system properties.
 * @see System#getProperty(String)
 */
@Override
public String get(String key) {
  Assert.hasText(key, "'key' must not be empty");
  return System.getProperty(key);
}

/**
 * Writes the given lines of text to this sink with each line (including the last) terminated with
 * the operating system's default line separator. This method is equivalent to {@code
 * writeLines(lines, System.getProperty("line.separator"))}.
 *
 * @throws IOException if an I/O error occurs while writing to this sink
 * @since 22.0
 */
@Beta
public void writeLines(Stream<? extends CharSequence> lines) throws IOException {
 writeLines(lines, System.getProperty("line.separator"));
}

/**
 * Writes the given lines of text to this sink with each line (including the last) terminated with
 * the operating system's default line separator. This method is equivalent to {@code
 * writeLines(lines, System.getProperty("line.separator"))}.
 *
 * @throws IOException if an I/O error occurs while writing to this sink
 */
public void writeLines(Iterable<? extends CharSequence> lines) throws IOException {
 writeLines(lines, System.getProperty("line.separator"));
}

/**
 * Returns the current value for this system property by delegating to {@link
 * System#getProperty(String)}.
 */
public @Nullable String value() {
 return System.getProperty(key);
}

public void testWriteLinesStream_systemDefaultSeparator() throws IOException {
 String separator = System.getProperty("line.separator");
 sink.writeLines(lines.stream());
 assertContainsExpectedLines(separator);
}

@BeforeClass
public static void compilerAssumptions() {
  // JiBX compiler is currently not compatible with JDK 9
  Assume.assumeTrue(System.getProperty("java.version").startsWith("1.8."));
}

@BeforeClass
public static void compilerAssumptions() {
  // JiBX compiler is currently not compatible with JDK 9
  Assume.assumeTrue(System.getProperty("java.version").startsWith("1.8."));
}

public void testWriteLines_stream() throws IOException {
 sink.writeLines(ImmutableList.of("foo", "bar", "baz").stream());
 String separator = System.getProperty("line.separator");
 assertEquals("foo" + separator + "bar" + separator + "baz" + separator, sink.getString());
}

public void testWriteLines_systemDefaultSeparator() throws IOException {
 String separator = System.getProperty("line.separator");
 sink.writeLines(lines);
 assertContainsExpectedLines(separator);
}

@Test
public void verifyPropertiesAreAvailableInEnvironment() {
  String userHomeKey = "user.home";
  assertEquals(System.getProperty(userHomeKey), env.getProperty(userHomeKey));
  assertEquals("enigma", env.getProperty("explicit"));
}

@Test
@EnabledOnMac
void enabledIfWithSpelOsCheckInCustomComposedAnnotation() {
  String os = System.getProperty("os.name").toLowerCase();
  assertTrue(os.contains("mac"), "This test must be enabled on Mac OS");
  assertFalse(os.contains("win"), "This test must be disabled on Windows");
}

public void testWriteLines_withDefaultSeparator() throws IOException {
 sink.writeLines(ImmutableList.of("foo", "bar", "baz"));
 String separator = System.getProperty("line.separator");
 assertEquals("foo" + separator + "bar" + separator + "baz" + separator, sink.getString());
}

@Test
@DisabledOnMac
void disabledIfWithSpelOsCheckInCustomComposedAnnotation() {
  assertFalse(System.getProperty("os.name").contains("Mac"), "This test must be disabled on Mac OS");
}

@Parameterized.Parameters(name = "server [{0}]")
public static Object[][] arguments() {
  File base = new File(System.getProperty("java.io.tmpdir"));
  return new Object[][] {
      {new JettyHttpServer()},
      {new ReactorHttpServer()},
      {new TomcatHttpServer(base.getAbsolutePath())},
      {new UndertowHttpServer()}
  };
}

@Test
public void testPropertyPlaceholderConfigurerWithSystemPropertyFallback() {
  factory.registerBeanDefinition("tb", genericBeanDefinition(TestBean.class)
      .addPropertyValue("country", "${os.name}").getBeanDefinition());
  PropertyPlaceholderConfigurer ppc = new PropertyPlaceholderConfigurer();
  ppc.postProcessBeanFactory(factory);
  TestBean tb = (TestBean) factory.getBean("tb");
  assertEquals(System.getProperty("os.name"), tb.getCountry());
}

public void testGetValue() {
 for (StandardSystemProperty property : StandardSystemProperty.values()) {
  assertEquals(System.getProperty(property.key()), property.value());
 }
}

@Test
public void testCustomDestroyBean() throws Exception {
  beanFactory.getBean("custom-destroy");
  beanFactory.destroySingletons();
  assertNull(System.getProperty("security.destroy"));
}

@Test
public void testSpringDestroyBean() throws Exception {
  beanFactory.getBean("spring-destroy");
  beanFactory.destroySingletons();
  assertNull(System.getProperty("security.destroy"));
}

@Test
public void testCustomFactoryType() throws Exception {
  assertNull(beanFactory.getType("spring-factory"));
  assertNull(System.getProperty("factory.object.type"));
}