reflection api give overloading on function's return type

I am using reflection APIs to do some queries on Java methods. Below is the code snippet to find out the return type of calling, say new java.lang.StringBuilder().append('a'):

Class<?> c = Class.forName("java.lang.StringBuilder");
Method[] mList = c.getMethods();

for (int i = 0; i < mList.length; i++) {
    if (mList[i].getName() == "append" 
          && mList[i].getParameterTypes().length == 1 
          && mList[i].getParameterTypes()[0].getCanonicalName() == "char") {
        System.out.println(mList[i]);
    }
}

Oddly, the output gives

public java.lang.AbstractStringBuilder java.lang.StringBuilder.append(char)

public java.lang.Appendable java.lang.StringBuilder.append(char) throws java.io.IOException

public java.lang.StringBuilder java.lang.StringBuilder.append(char)

while the Java API Specification only gives StringBuilder as the return type. Does that mean the method append actually overloads on return type?