43 lines
1.3 KiB
Java
43 lines
1.3 KiB
Java
//: typeinfo/ModifyingPrivateFields.java
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import java.lang.reflect.*;
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class WithPrivateFinalField {
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private int i = 1;
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private final String s = "I'm totally safe";
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private String s2 = "Am I safe?";
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@Override
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public String toString() {
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return "i = " + i + ", " + s + ", " + s2;
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}
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}
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public class ModifyingPrivateFields {
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public static void main(String[] args) throws Exception {
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WithPrivateFinalField pf = new WithPrivateFinalField();
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System.out.println(pf);
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Field f = pf.getClass().getDeclaredField("i");
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f.setAccessible(true);
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System.out.println("f.getInt(pf): " + f.getInt(pf));
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f.setInt(pf, 47);
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System.out.println(pf);
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f = pf.getClass().getDeclaredField("s");
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f.setAccessible(true);
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System.out.println("f.get(pf): " + f.get(pf));
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f.set(pf, "No, you're not!");
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System.out.println(pf);
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f = pf.getClass().getDeclaredField("s2");
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f.setAccessible(true);
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System.out.println("f.get(pf): " + f.get(pf));
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f.set(pf, "No, you're not!");
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System.out.println(pf);
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}
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} /* Output:
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i = 1, I'm totally safe, Am I safe?
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f.getInt(pf): 1
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i = 47, I'm totally safe, Am I safe?
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f.get(pf): I'm totally safe
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i = 47, I'm totally safe, Am I safe?
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f.get(pf): Am I safe?
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i = 47, I'm totally safe, No, you're not!
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*///:~
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