Always handle null values explicitly and consistently throughout your codebase to prevent null pointer exceptions. Follow these guidelines: 1. **Validate nulls early** using Preconditions to provide clear error messages: ```java // Use explicit null checks with informative messages Preconditions.checkNotNull(input, "Input cannot be null"); Preconditions.checkArgument(shape != null && shape.length > 0, "Invalid shape: %s", shape); ``` 2. **Document null behavior** clearly in Javadoc comments: ```java /** * Creates a buffer in the specified workspace. * @param workspace Optional memory workspace to define the buffer in, may be null * (buffer not created in workspace when null) */ public DataBuffer createBuffer(DataType dataType, long length, boolean initialize, MemoryWorkspace workspace) { // Implementation } ``` 3. **Handle nulls at the source** rather than requiring downstream methods to handle them, preventing defensive null checks throughout the codebase. 4. **Use appropriate types** for potentially null values from collections: ```java // Instead of: int numWords = (int) tokenizerConfig.get("num_words"); // Use: Integer numWords = (Integer) tokenizerConfig.get("num_words"); ``` 5. **Consider using annotations** like `@NonNull` or `@Nullable` to clearly indicate intent and enable static analysis tools to catch potential null issues. Following these practices helps prevent null pointer exceptions and makes code more robust and maintainable.