Java 8 processing character stitching has NULL problem

We must deal with character stitching during the development process. If the stitching characters are empty, NULL will appear, so what should we do. Let's use the Java8 attribute to deal with it.

		String a = "Shanghai";
        String b =null;
                 String C = "Huaihai Road";
        String value = MessageFormat.format("{0}{1}{2}",Optional.ofNullable(a).orElse("")
                ,Optional.ofNullable(b).orElse("")
                ,Optional.ofNullable(c).orElse(""));

        System.out.println("---->"+a+b+c);
        System.out.println("****"+value);

It can be seen that optional.ofnullable (xx) .orelse (""); When the xx parameter is empty, we can use "" by default afterwards, and it can also be replaced with other default values.

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