Five Snippets: What Prints, and in What Order

Five short pieces. For each, write down everything printed and the order, or that it fails to compile. All five before the reveal.

java

// 1
try { System.out.print("a"); throw new RuntimeException(); }
catch (RuntimeException e) { System.out.print("b"); }
finally { System.out.print("c"); }

// 2
try { return 1; } finally { System.out.print("d"); }

// 3
try { throw new IOException(); }
catch (IOException e) { System.out.print("e"); }
catch (Exception e) { System.out.print("f"); }

// 4
try { throw new IOException(); }
catch (Exception e) { System.out.print("g"); }
catch (IOException e) { System.out.print("h"); }

// 5
try (Scanner s = new Scanner("x")) { System.out.print("i"); }
finally { System.out.print("j"); }

The five results

Each snippet, what it does, and the rule behind it
Snippet	Result	Rule
1	`abc`	`try` up to the throw, the matching `catch`, then `finally`
2	`d`, then returns 1	`finally` runs on every way out, including a `return`
3	`e`	First matching `catch` wins; the wider one is never reached
4	Does not compile	`IOException` is already covered by the `Exception` above it
5	`ij`	The resource closes before `finally`, and closing prints nothing

Snippet four is the one worth keeping. Ordering catch blocks from wide to narrow is a compile error rather than a silent problem, which is one of the few places Java refuses to let you write the unreachable version.