JavaCopExplosion.java

import com.sun.tools.javac.util.List;
import org.checkerframework.checker.nullness.qual.*;

@org.checkerframework.framework.qual.DefaultQualifier(Nullable.class)
class Explosion {
    public static class ExplosiveException extends Exception {}

    @NonNull Integer m_nni = 1;
    final String m_astring;

    Explosion() {
        // m_nni = 1;\
        m_astring = "hi";
        try {
            throw new RuntimeException();
        } catch (Exception e) {
            System.out.println(m_astring.length());
        }
        return;
    }

    static void main(String @NonNull [] args) {
        @NonNull String s = "Dan";
        String s2;
        s2 = null;
        //:: warning: (known.nonnull)
        if (s2 != null || s != null) {
            //:: error: (assignment.type.incompatible)
            s = s2;
        } else {
            s = new String("Levitan");
        }
        s2 = args[0];
        //:: error: (dereference.of.nullable)
        System.out.println("Possibly cause null pointer with this: " + s2.length());
        //:: warning: (known.nonnull)
        if (s2 == null) {
            // do nothing
        } else {
            System.out.println("Can't cause null pointer here: " + s2.length());
            s = s2;
        }
        //:: warning: (known.nonnull)
        if (s == null ? s2 != null : s2 != null) {
            s = s2;
        }
        System.out.println("Hello " + s);
        System.out.println("Hello " + s.length());
        f();
    }

    private static int f() {
        while (true) {
            try {
                throw new ExplosiveException();
            } finally {
                // break;
                return 1;
                // throw new RuntimeException();
            }
        }
    }

    public static int foo() {
        final int v;
        int x;
        Integer z;
        Integer y;
        @NonNull Integer nnz = 3;
        z = new Integer(5);
        try {
            x = 3;
            x = 5;
            // y = z;
            nnz = z;
            z = null;
            //:: error: (assignment.type.incompatible)
            nnz = z;

            while (z == null) {
                break;
            }
            //:: error: (assignment.type.incompatible)
            nnz = z;
            while (z == null) {
                // do nothing
            }
            nnz = z;
            // v = 1;
            return 1;
            // v = 2;
            // throw new RuntimeException ();
        } catch (NullPointerException e) {
            e.printStackTrace();
            // e = null;
            // v = 1;
        } catch (RuntimeException e) {
            // nnz = z;
            // v = 2;
        } finally {
            // v = 1 + x;
        }
        return 1;
        // return v + x;
    }

    private void bar(List<@NonNull String> ss, String b, String c) {
        @NonNull String a;
        //:: error: (iterating.over.nullable)
        for (@NonNull String s : ss) {
            a = s;
        }
        if (b == null || b.length() == 0) {
            System.out.println("hey");
        }
        if (b != null) {
            //:: error: (dereference.of.nullable)
            for (; b.length() > 0; b = null) {
                System.out.println(b.length());
            }
        }
    }
}