SubjectCallable.java

package com.hwlcn.security.subject.support;

import com.hwlcn.security.subject.Subject;
import com.hwlcn.security.util.ThreadState;

import java.util.concurrent.Callable;

public class SubjectCallable<V> implements Callable<V> {

    protected final ThreadState threadState;
    private final Callable<V> callable;

    public SubjectCallable(Subject subject, Callable<V> delegate) {
        this(new SubjectThreadState(subject), delegate);
    }

    protected SubjectCallable(ThreadState threadState, Callable<V> delegate) {
        if (threadState == null) {
            throw new IllegalArgumentException("ThreadState argument cannot be null.");
        }
        this.threadState = threadState;
        if (delegate == null) {
            throw new IllegalArgumentException("Callable delegate instance cannot be null.");
        }
        this.callable = delegate;
    }

    public V call() throws Exception {
        try {
            threadState.bind();
            return doCall(this.callable);
        } finally {
            threadState.restore();
        }
    }

    protected V doCall(Callable<V> target) throws Exception {
        return target.call();
    }
}