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So, blah defines an instance field called Neither Think of it like identical twins, they might share commonality, but just because one get’s sick, doesn’t mean the other will, they are their own self contained instance.<\/p>\n IF you want to share information between classes, you should consider providing a reference to the class with the information you want to share, for example…<\/p>\n But I’d really like to see a use case for something so drastic…<\/p>\n Lets assume…<\/p>\n Now in your code, you do something like…<\/p>\n Okay, so far, so good. Now imagine, somewhere else in your code, you do…<\/p>\n …But why hasn’t the screen updated? Because This is pain in the debugger to find, even when you know what you are looking for, because there is no accountability, any class that extends label<\/code> but does not initialise it<\/p>\npublic abstract class Blah \n{\n protected JLabel label;\n}\n<\/code><\/pre>\nBlahChildOne<\/code> initialises the label<\/code> from Blah<\/code><\/p>\npublic class BlahChildOne extends Blah\n{\n public BlahChildOne()\n {\n label = new JLabel();\n }\n}\n<\/code><\/pre>\nBlahChildTwo<\/code> does not initialises the label<\/code> from Blah<\/code>, so it is still null<\/code>…<\/p>\npublic class BlahChildTwo extends Blah\n{\n public BlahChildTwo()\n {\n label.setText(\"Fred\");\n }\n}\n<\/code><\/pre>\nBlahChildOne<\/code> or BlahChildTwo<\/code> share information between them (they have commonality through inheritance from Blah<\/code>, but the actually information is each owns).<\/p>\npublic class BlahChildTwo extends Blah\n{\n public BlahChildTwo(Blah blah)\n {\n label = blah.label;\n label.setText(\"Fred\");\n }\n}\n<\/code><\/pre>\nWhy
static<\/code> is consider bad<\/strong><\/h2>\npublic abstract class Blah \n{\n protected static JLabel label;\n}\n<\/code><\/pre>\nBlahChildOne bco = new BlahChildOne();\nadd(bco.label); \/\/ It the label to the screen...\nBlahChildTwo bct = new BlahChildTwo();\n<\/code><\/pre>\nBlahChildOne bco = new BlahChildOne();\nBlahChildTwo bct = new BlahChildTwo();\n<\/code><\/pre>\nBlah#label<\/code> is no longer pointing to the JLabel<\/code> which you previously added to the screen, you’ve lost that reference.<\/p>\nBlah<\/code> can create a new instance of JLabel<\/code> and assign it to label<\/code>.<\/p>\n<\/p><\/div>\n