A catch clause that only rethrows the caught exception has the same effect as omitting the catch altogether and letting it bubble up automatically, but with more code and the additional detriment of leaving maintainers scratching their heads.

Such clauses should either be eliminated or populated with the appropriate logic.

Noncompliant Code Example

public String readFile(File f) {
  StringBuilder sb = new StringBuilder();
  try {
    FileReader fileReader = new FileReader(fileName);
    BufferedReader bufferedReader = new BufferedReader(fileReader);

    while((line = bufferedReader.readLine()) != null) {
      //...
  }
  catch (IOException e) {  // Noncompliant
    throw e;
  }
  return sb.toString();
}

Compliant Solution

public String readFile(File f) {
  StringBuilder sb = new StringBuilder();
  try {
    FileReader fileReader = new FileReader(fileName);
    BufferedReader bufferedReader = new BufferedReader(fileReader);

    while((line = bufferedReader.readLine()) != null) {
      //...
  }
  catch (IOException e) {
    logger.LogError(e);
    throw e;
  }
  return sb.toString();
}

or

public String readFile(File f) throws IOException {
  StringBuilder sb = new StringBuilder();
  FileReader fileReader = new FileReader(fileName);
  BufferedReader bufferedReader = new BufferedReader(fileReader);

  while((line = bufferedReader.readLine()) != null) {
    //...

  return sb.toString();
}