9aca4314df
## Review A dedicated reviewer checked the rule description successfully for: - [ ] logical errors and incorrect information - [ ] information gaps and missing content - [ ] text style and tone - [ ] PR summary and labels follow [the guidelines](https://github.com/SonarSource/rspec/#to-modify-an-existing-rule) --------- Co-authored-by: Loris S <91723853+loris-s-sonarsource@users.noreply.github.com> Co-authored-by: leonardo-pilastri-sonarsource <115481625+leonardo-pilastri-sonarsource@users.noreply.github.com>
75 lines
1.9 KiB
Plaintext
75 lines
1.9 KiB
Plaintext
The variable `myObject` is equal to `null`, meaning it has no value:
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[source,java,diff-id=1,diff-type=noncompliant]
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----
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public void method() {
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Object myObject = null;
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System.out.println(myObject.toString()); // Noncompliant: myObject is null
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}
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----
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The parameter `input` might be `null` as suggested by the `if` condition:
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[source,java,diff-id=2,diff-type=noncompliant]
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----
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public void method(Object input)
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{
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if (input == null)
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{
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// ...
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}
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System.out.println(input.toString()); // Noncompliant
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}
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----
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The unboxing triggered in the return statement will throw a `NullPointerException`:
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[source,java,diff-id=3,diff-type=noncompliant]
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----
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public boolean method() {
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Boolean boxed = null;
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return boxed; // Noncompliant
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}
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----
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Both `conn` and `stmt` might be `null` in case an exception was thrown in the try{} block:
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[source,java,diff-id=4,diff-type=noncompliant]
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----
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Connection conn = null;
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Statement stmt = null;
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try {
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conn = DriverManager.getConnection(DB_URL,USER,PASS);
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stmt = conn.createStatement();
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// ...
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} catch(Exception e) {
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e.printStackTrace();
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} finally {
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stmt.close(); // Noncompliant
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conn.close(); // Noncompliant
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}
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----
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As `getName()` is annotated with `@CheckForNull`, there is a risk of `NullPointerException` here:
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[source,java,diff-id=5,diff-type=noncompliant]
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----
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@CheckForNull
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String getName() {...}
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public boolean isNameEmpty() {
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return getName().length() == 0; // Noncompliant
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}
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----
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As `merge(...)` parameter is annotated with `@Nonnull`, passing an identified potential null value (thanks to @CheckForNull) is not safe:
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[source,java,diff-id=6,diff-type=noncompliant]
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----
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private void merge(@Nonnull Color firstColor, @Nonnull Color secondColor) {...}
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public void append(@CheckForNull Color color) {
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merge(currentColor, color); // Noncompliant: color should be null-checked because merge(...) doesn't accept nullable parameters
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}
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----
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