@Override
	public boolean equals(Object obj) {

		if (obj == null) {
			return false;
		}
		if (this == obj) {
			return true;
		}
		if (getClass() != obj.getClass()) {
			return false;
		}

		ProgramNode other = (ProgramNode) obj;
		if (!SystemUtilities.isEqual(parentModule, other.parentModule)) {
			return false;
		}

		// Note: 'group' is a DB object--there can be only one
		return SystemUtilities.isEqual(group, other.group);
	}
Returns whether some other object is "equal to" this one.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/programtree/ProgramNode.java