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import org.checkerframework.checker.lock.qual.*;
public class Fields {
class MyClass {
public Object field;
}
static @GuardedBy("Fields.class") MyClass lockedStatically;
static synchronized void ssMethod() {
lockedStatically.field = new Object();
}
@GuardedBy("lockingObject") MyClass locked;
final Object lockingObject = new Object();
synchronized void wrongLock1() {
// locking over wrong lock
// :: error: (lock.not.held)
locked.field = new Object(); // error
}
synchronized void wrongLock2() {
// locking over wrong lock
synchronized (this) {
// :: error: (lock.not.held)
locked.field = new Object(); // error
}
}
void rightLock() {
synchronized (lockingObject) {
locked.field = new Object();
}
// accessing after the synchronized object
// :: error: (lock.not.held)
locked.field = new Object(); // error
}
@Holding("lockingObject")
void usingHolding() {
locked.field = new Object();
}
@GuardedBy("this") MyClass lockedByThis;
void wrongLocksb() {
// without locking
// :: error: (lock.not.held)
lockedByThis.field = new Object(); // error
synchronized (Fields.class) {
// :: error: (lock.not.held)
lockedByThis.field = new Object(); // error
}
}
void rightLockb() {
synchronized (this) {
lockedByThis.field = new Object();
}
// accessing after the synchronized object
// :: error: (lock.not.held)
lockedByThis.field = new Object(); // error
}
synchronized void synchronizedMethodb() {
lockedByThis.field = new Object();
}
void test() {
// synchronized over the right object
final Fields a = new Fields();
final Fields b = new Fields();
synchronized (this) {
lockedByThis.field = new Object();
// :: error: (lock.not.held)
a.lockedByThis.field = new Object(); // error
// :: error: (lock.not.held)
b.lockedByThis.field = new Object(); // error
}
synchronized (a) {
// :: error: (lock.not.held)
lockedByThis.field = new Object(); // error
a.lockedByThis.field = new Object();
// :: error: (lock.not.held)
b.lockedByThis.field = new Object(); // error
}
synchronized (b) {
// :: error: (lock.not.held)
lockedByThis.field = new Object(); // error
// :: error: (lock.not.held)
a.lockedByThis.field = new Object(); // error
b.lockedByThis.field = new Object();
}
}
}
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