logback-android/src/main/java/ch/qos/logback/core/joran/action/PropertyAction.java
public void begin(InterpretationContext ec, String localName,
      Attributes attributes) {

    if ("substitutionProperty".equals(localName)) {
      addWarn("[substitutionProperty] element has been deprecated. Please use the [property] element instead.");
    }

    String name = attributes.getValue(NAME_ATTRIBUTE);
    String value = attributes.getValue(VALUE_ATTRIBUTE);
    String scopeStr = attributes.getValue(SCOPE_ATTRIBUTE);

    Scope scope = ActionUtil.stringToScope(scopeStr);

    if (checkFileAttributeSanity(attributes)) {
      String file = attributes.getValue(FILE_ATTRIBUTE);
      file = ec.subst(file);
      try {
        FileInputStream istream = new FileInputStream(file);
        loadAndSetProperties(ec, istream, scope);
      } catch (FileNotFoundException e) {
        addError("Could not find properties file [" + file + "].");
      } catch (IOException e1) {
        addError("Could not read properties file [" + file + "].", e1);
      }
    } else if (checkResourceAttributeSanity(attributes)) {
      String resource = attributes.getValue(RESOURCE_ATTRIBUTE);
      resource = ec.subst(resource);
      URL resourceURL = Loader.getResourceBySelfClassLoader(resource);
      if (resourceURL == null) {
        addError("Could not find resource [" + resource + "].");
      } else {
        try {
          InputStream istream = resourceURL.openStream();
          loadAndSetProperties(ec, istream, scope);
        } catch (IOException e) {
          addError("Could not read resource file [" + resource + "].", e);
        }
      }
    } else if (checkValueNameAttributesSanity(attributes)) {
      value = RegularEscapeUtil.basicEscape(value);
      // now remove both leading and trailing spaces
      value = value.trim();
      value = ec.subst(value);
      ActionUtil.setProperty(ec, name, value, scope);

    } else {
      addError(INVALID_ATTRIBUTES);
    }
  }
public void begin(InterpretationContext ec, String localName,
      Attributes attributes) {

    if ("substitutionProperty".equals(localName)) {
      addWarn("[substitutionProperty] element has been deprecated. Please use the [property] element instead.");
    }

    String name = attributes.getValue(NAME_ATTRIBUTE);
    String value = attributes.getValue(VALUE_ATTRIBUTE);
    String scopeStr = attributes.getValue(SCOPE_ATTRIBUTE);

    Scope scope = ActionUtil.stringToScope(scopeStr);

    if (checkFileAttributeSanity(attributes)) {
      String file = attributes.getValue(FILE_ATTRIBUTE);
      file = ec.subst(file);
      try {
        FileInputStream istream = new FileInputStream(file);
        loadAndSetProperties(ec, istream, scope);
      } catch (FileNotFoundException e) {
        addError("Could not find properties file [" + file + "].");
      } catch (IOException e1) {
        addError("Could not read properties file [" + file + "].", e1);
      }
    } else if (checkResourceAttributeSanity(attributes)) {
      String resource = attributes.getValue(RESOURCE_ATTRIBUTE);
      resource = ec.subst(resource);
      URL resourceURL = Loader.getResourceBySelfClassLoader(resource);
      if (resourceURL == null) {
        addError("Could not find resource [" + resource + "].");
      } else {
        try {
          InputStream istream = resourceURL.openStream();
          loadAndSetProperties(ec, istream, scope);
        } catch (IOException e) {
          addError("Could not read resource file [" + resource + "].", e);
        }
      }
    } else if (checkValueNameAttributesSanity(attributes)) {
      value = RegularEscapeUtil.basicEscape(value);
      // now remove both leading and trailing spaces
      value = value.trim();
      value = ec.subst(value);
      ActionUtil.setProperty(ec, name, value, scope);

    } else {
      addError(INVALID_ATTRIBUTES);
    }
  }
Set a new property for the execution context by name, value pair, or adds
all the properties found in the given file.