Attachment #209741 for bug #247564

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			"public class X {\n" +
			"  Object o;\n" +
			"  void foo() {\n" +
			"      o = null;\n" +
			"  }\n" +
			"  void foo1() {\n" + 
			"	 o.toString();\n" +

			"            if (field == null) { \n" +
			"                field = new Object();\n" +
			"            }\n" +
			"            field.toString(); // Wrong outcome was: Pot. NPE\n" +
			"            i--;\n" +
			"        }\n" +
			"    }\n" +

			"  }\n" +
			"  void foo1() {\n" +
			"    if (o == null) {\n" +
			"        o.toString(); // danger\n" +
			"        return;\n" +
			"    }\n" +
			"	 o.toString(); // safe\n" +

			"}\n"},
			"----------\n" + 
			"1. ERROR in X.java (at line 13)\n" + 
			"	o.toString(); // danger\n" + 
			"	^\n" + 
			"Null pointer access: The field o can only be null at this location\n" + 
			"----------\n" + 
			"2. ERROR in X.java (at line 22)\n" + 
			"	o.toString(); // uncertain\n" + 
			"	^\n" + 
			"Potential null pointer access: The field o may be null at this location\n" + 

			"  }\n" +
			"  void foo1() {\n" +
			"    if (o == null) {\n" +
			"        o.toString(); // danger\n" +
			"        return;\n" +
			"    }\n" +
			"	 o.toString(); // safe\n" +

			"}\n"},
			"----------\n" + 
			"1. ERROR in X.java (at line 39)\n" + 
			"	o.toString(); // danger\n" + 
			"	^\n" + 
			"Null pointer access: The field o can only be null at this location\n" + 
			"----------\n" + 
			"2. ERROR in X.java (at line 48)\n" + 
			"	o.toString(); // uncertain\n" + 
			"	^\n" + 
			"Potential null pointer access: The field o may be null at this location\n" + 

			"	 if (o == null) {\n" +	// don't know o's nullness, so silent
			"		o.toString();\n" + // report NPE
			"	 }\n" +
			"    local.toString();\n" + // try to diffuse status for o / o2
			"	 o.toString();\n" +	// already reported NPE above. So silent. Same behaviour as 'local'
			"	 if (o2 == null) {\n" + // report always false null check
			"		o2.toString();\n" + // dead code

			"	^\n" + 
			"Null pointer access: The field o can only be null at this location\n" + 
			"----------\n" + 
			"4. ERROR in X.java (at line 23)\n" + 
			"	if (o2 == null) {\n" + 
			"	    ^^\n" + 
			"Null comparison always yields false: The field o2 cannot be null at this location\n" + 
			"----------\n" + 
			"5. WARNING in X.java (at line 23)\n" + 
			"	if (o2 == null) {\n" + 
			"		o2.toString();\n" + 
			"	 }\n" + 

	);
}

// null analysis -- case for static final field initialized inside static block with different values
// check if the resetting works properly i.e. null status for constant fields should not be 
// reset on method calls. This test is for constructors
public void testBug247564b_6() {
	this.runNegativeTest(
		new String[] {

			"	 if (o == null) {\n" +	// don't know o's nullness, so silent
			"		o.toString();\n" + // report NPE
			"	 }\n" +
			"    local.toString();\n" + // try to diffuse status for o / o2
			"	 o.toString();\n" +	// already reported NPE above. So silent. Same behaviour as 'local'
			"	 if (o2 == null) {\n" + // report always false null check
			"		o2.toString();\n" + // dead code

			"	^\n" + 
			"Null pointer access: The field o can only be null at this location\n" + 
			"----------\n" + 
			"4. ERROR in X.java (at line 23)\n" + 
			"	if (o2 == null) {\n" + 
			"	    ^^\n" + 
			"Null comparison always yields false: The field o2 cannot be null at this location\n" + 
			"----------\n" + 
			"5. WARNING in X.java (at line 23)\n" + 
			"	if (o2 == null) {\n" + 
			"		o2.toString();\n" + 
			"	 }\n" + 

	);
}

// null analysis -- case for static final field initialized inside static block with different values
// check if the resetting works properly i.e. null status for constant fields should not be 
// reset on method calls. This test is for constructors
public void testBug247564b_6_2() {
	this.runNegativeTest(
		new String[] {

			"	 if (o == null) {\n" +	// don't know o's nullness, so silent
			"		o.toString();\n" + // report NPE
			"	 }\n" +
			"    local.toString();\n" + // try to diffuse status for o / o2
			"	 o.toString();\n" +	// already reported NPE above. So silent. Same behaviour as 'local'
			"	 if (o2 == null) {\n" + // report always false null check
			"		o2.toString();\n" + // dead code

			"	^\n" + 
			"Null pointer access: The field o can only be null at this location\n" + 
			"----------\n" + 
			"4. ERROR in X.java (at line 49)\n" + 
			"	if (o2 == null) {\n" + 
			"	    ^^\n" + 
			"Null comparison always yields false: The field o2 cannot be null at this location\n" + 
			"----------\n" + 
			"5. WARNING in X.java (at line 49)\n" + 
			"	if (o2 == null) {\n" + 
			"		o2.toString();\n" + 
			"	 }\n" + 

			"	 if (o1 == null) {\n" +	// can't be null, was dereferenced in static initializer
			"		o1.toString();\n" + // dead
			"	 }\n" +
			"    local.toString();\n" + // try to diffuse status for o1 / o2
			"	 o1.toString();\n" +	// safe
			"	 if (o2 == null) {\n" + // report always false null check
			"		o2.toString();\n" + // dead code

			"	                ^^^^^^^^^^^^^^^^^^^^^^\n" + 
			"Dead code\n" + 
			"----------\n" + 
			"6. ERROR in X.java (at line 23)\n" + 
			"	if (o2 == null) {\n" + 
			"	    ^^\n" + 
			"Null comparison always yields false: The field o2 cannot be null at this location\n" + 
			"----------\n" + 
			"7. WARNING in X.java (at line 23)\n" + 
			"	if (o2 == null) {\n" + 
			"		o2.toString();\n" + 
			"	 }\n" + 

			"	 if (o1 == null) {\n" +	// report redundant null check
			"		o1.toString();\n" + // report NPE
			"	 }\n" +
			"    local.toString();\n" + // try to diffuse status for o1 / o2
			"	 o1.toString();\n" +	// already reported NPE above. So silent. Same behaviour as 'local'
			"	 if (o2 == null) {\n" + // report always false null check
			"		o2.toString();\n" + // dead code

		"	^^\n" + 
		"Null pointer access: The field o1 can only be null at this location\n" + 
		"----------\n" + 
		"5. ERROR in X.java (at line 41)\n" + 
		"	if (o2 == null) {\n" + 
		"	    ^^\n" + 
		"Null comparison always yields false: The field o2 cannot be null at this location\n" + 
		"----------\n" + 
		"6. WARNING in X.java (at line 41)\n" + 
		"	if (o2 == null) {\n" + 
		"		o2.toString();\n" + 
		"	 }\n" + 

			"	 if (o1 == null) {\n" +	// report redundant null check
			"		o1.toString();\n" + // report NPE
			"	 }\n" +
			"    local.toString();\n" + // try to diffuse status for o1 / o2
			"	 o1.toString();\n" +	// already reported NPE above. So silent. Same behaviour as 'local'
			"	 if (o2 == null) {\n" + // report always false null check
			"		o2.toString();\n" + // dead code

		"	^^\n" + 
		"Null pointer access: The field o1 can only be null at this location\n" + 
		"----------\n" + 
		"5. ERROR in X.java (at line 19)\n" + 
		"	if (o2 == null) {\n" + 
		"	    ^^\n" + 
		"Null comparison always yields false: The field o2 cannot be null at this location\n" + 
		"----------\n" + 
		"6. WARNING in X.java (at line 19)\n" + 
		"	if (o2 == null) {\n" + 
		"		o2.toString();\n" + 
		"	 }\n" + 

	);
}

// null analysis -- test redundant instanceof warning for static final fields
public void testBug247564e_1() {
	this.runNegativeTest(
		new String[] {
			"X.java",
			"public class X {\n" +
			"  static final Object o = null;\n" +
			"  void foo() {\n" +
			"      if (o instanceof X) return;\n" +
			"  }\n" +
			"}"},
		"----------\n" + 
		"1. ERROR in X.java (at line 4)\n" + 
		"	if (o instanceof X) return;\n" + 
		"	    ^\n" + 
		"instanceof always yields false: The field o can only be null at this location\n" + 
		"----------\n",
		JavacTestOptions.Excuse.EclipseWarningConfiguredAsError);
}

// null analysis -- test potential null ptr access warning because of static field access through object returned by method call
public void testBug247564f() {
	Map compilerOptions = getCompilerOptions();

			"      if (this.field99 == null && this.field99.hashCode() == 0){}\n" +
			"	   this.field98 = null;\n" +
			"	}\n" +
			"	if (this.field98.hashCode() == 0) {}\n" +
			"	this.field97 = null;\n" +
			"	if (this.field97.hashCode() == 0) {}\n" +
			"	if (this.field100.hashCode() == 0) {}\n" +

}

// null analysis -- simple case for field for inner class
// to make sure that id's of local variables in inner classes don't conflict with those of fields.
public void testBug247564h_1() {
	this.runNegativeTest(
		new String[] {

}

// null analysis -- simple case for field for inner class
// to make sure that id's of local variables in inner classes don't conflict with those of fields.
public void testBug247564h_2() {
	this.runNegativeTest(
		new String[] {

			"	 class X2 {\n" +
			"	 	Object field4;\n" +
			"	 	Object field5;\n" +
			"	    void goo(Object var) {\n" +
			"    	   if (var == null && field4.toString() == \"\"){}\n" +
			"    	   if (var == null && field5.toString() == \"\"){}\n" +
			"    	   if (field3 == null && field3.toString() == \"\"){}\n" +
			"    	   if (field3 == null && field1.toString() == \"\"){}\n" +
			"       }\n" +
			"    }\n" +
			"    Object field22;\n" +
			"  }\n" +
			"}\n"},
		"----------\n" + 

			"    	if (X.field0 == null && X.field0.toString() == \"\"){}\n" +   // warn
			"    	if (this.field0 == null && X.field0.toString() == \"\"){}\n" +   // warn
			"    	if (X.field0 == null && this.field0.toString() == \"\"){}\n" +   // warn
			"    	if (X.field0 == null && getX().field0.toString() == \"\"){}\n" +   // no warn (diffused by getX() call)
			"  }\n" +
			"}\n" +
			"class Y{\n" +

			"  static Y getY(){ return new Y();}\n" +
			"  static X getX() { return new X();}\n" +
			"  static class XInner{\n" +
			"    static Object xinnerfield;\n" +
			"    XInner getXInner() { return new XInner();\n}" +
			"    void goo(Object var) {\n" +
			"    	if (new Y().getY().yField1 == null && field0.toString() == \"\"){}\n" +  // no warn
			"    	if (getY().yField1 == null && field0.toString() == \"\"){}\n" +  // no warn
			"    	if (new Y().getX().field0 == null && field0.toString() == \"\"){}\n" +   // warn

			"    	if (Y.xiny.field1 == null && Y.yField1.toString() == \"\"){}\n" +  // no warn
			"    	if (X.field0 == null && X.field0.toString() == \"\"){}\n" +   // warn
			"    	if (X.field0 == null && getX().field0.toString() == \"\"){}\n" +   // no warn
			"    }\n" +
			"  }\n" +
			"}\n" +
			"class Y{\n" +

	this.runNegativeTest(
		new String[] {
			"X.java",
			"class MyException extends Exception{}\n" +
			"public class X {\n" +
			"  private Object f;\n" +
			"	 void gooCalls() throws MyException{}\n" +

			"}\n"},
		"----------\n" + 
		"1. WARNING in X.java (at line 1)\n" + 
		"	class MyException extends Exception{}\n" + 
		"	      ^^^^^^^^^^^\n" + 
		"The serializable class MyException does not declare a static final serialVersionUID field of type long\n" + 
		"----------\n" + 
		"2. ERROR in X.java (at line 12)\n" + 
		"	f.toString();\n" + 
		"	^\n" + 
		"Potential null pointer access: The field f may be null at this location\n" + 

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