Java – A better way to continue after an exception in Java

Let’s say I have to read from a file and then construct a java object from it.

PersonData p = new PersonData();
p.setName(readTokenAsString());
p.setAge(AgeConverter.createFromDateOfBirth(readTokenAsString()));   this throws a checked exception if the date of birth is mal-formed.

//... a list of methods that throws exception as AgeConverter

The behavior I want: If there is a problem with one property, ignore it and move on to the others.

I can think of a solution:

try {
  p.setAge1(...);
} catch (Exception e) {
  log and ignore
}

try {
  p.setAge2(...);
} catch (Exception e) {
  log and ignore
}

repeat for each attribute

Question:

Is there a better way to avoid duplication? Maybe functional style?

a) If I can’t modify the PersonData class, what’s the best approach.
b) If I could override the PersonData class, what would be the best approach.

Given your current statement, I will proceed as follows.

Define an @FunctionalInterface to which you can pass I/O logic:

@FunctionalInterface
public interface CheckedSupplier<T> {
    T getValue() throws Exception;
}

Define a practical method that uses @FunctionaInterface:

public static final <T> T getValueWithDefault(CheckedSupplier<T> supplier, T defaultValue) {
    try {
        return supplier.getValue();
    } catch (Exception e){
        return defaultValue;
    }
}

The practical method used is as follows:

PersonData p = new PersonData();
p.setName(getValueWithDefault(() -> readTokenAsString(), "default"));
p.setAge(getValueWithDefault(() -> AgeConverter.createFromDateOfBirth(readTokenAsString()), 0));

This solves the problem whether you want to modify the PersonData class or not.