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41 lines
627 B
41 lines
627 B
5 years ago
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A parameter of the overridden method is missing a @Nullable annotation present in the superclass.
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Action: choose a consistent annotation based on the desired invariant.
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Example:
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```java
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class A {
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int len(@Nullable String s) {
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if (s != null) {
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return s.length();
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} else {
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return 0;
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}
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}
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}
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class B extends A {
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int len(String s) { // @Nullable missing.
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return s.length();
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}
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}
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```
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A consistent use of @Nullable on parameters across subtyping should prevent runtime issue like in:
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```java
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public class Main {
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String s;
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int foo() {
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A a = new B();
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return a.len(s);
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}
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}
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```
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