有时 Properties.load() 跳过行

Question

Properties.load() skip the second line of InputStream in the following case. Is it a bug or normal behaviour of Java?

public class PropTest {
    public static void main(String[] args) throws Exception {
        propTest("Test1", "prop=cat,\\" + System.lineSeparator() + "dog");
        propTest("Test2", "prop=cat,\\  " + System.lineSeparator() + "dog");
    }
    public static void propTest(String name, String test) throws Exception {
        ByteArrayInputStream stream = new ByteArrayInputStream(test.getBytes());
        Properties properties = new Properties();
        properties.load(stream);
        System.out.println(properties.get("prop"));
    }
}

Running this code results the following:

cat,dog

cat,

Answer 1

According to the Properties file format

A property value can span several lines if each line is terminated by a backslash ('\') character.

You have a trailing space in the second version. So the line isn't continued. Note the whitespace rules, which are a bit confusing.

White space that appears between the property name and property value is ignored,

and

White space at the beginning of the line is also ignored.

So that means white space at the end of the line isn't explicitly ignored.