Termination of the given JBC could be disproven:

(0) Obligation:

JBC Problem based on JBC Program:

package simple.fib;

public class Fibonacci {

	public static void fib(int n) {
		int i = 0;
		int j = 1;
		int t = 0;
		while (j != n) {
			t = j+i;
			i = j;
			j = t;
		}
	}
}


package simple.fib;

public class Main {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		Fibonacci.fib(args.length);
	}

}

(1) JBCNonTerm (EQUIVALENT transformation)

Reached a loop using the following run:
0:

java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a112(lv_0_0)]
<simple.fib.Main.main||0: load ADDR args||args: a112|| ->
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a114
	String.CASE_INSENSITIVE_ORDER: o68
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	i123: [0,+inf)(2){0,+inf}
	a112([java.lang.String...]): length i123
	a114([java.io.ObjectStreamField|]): length iconst_0
	o68!: String$CaseInsensitiveComparator()
Relations: 

1:

java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a112(lv_0_0)]
<simple.fib.Main.main||1: arraylength|| - ||a112>
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a114
	String.CASE_INSENSITIVE_ORDER: o68
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	i123: [0,+inf)(2){0,+inf}
	a112([java.lang.String...]): length i123
	a114([java.io.ObjectStreamField|]): length iconst_0
	o68!: String$CaseInsensitiveComparator()
Relations: 

2:

java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a112(lv_0_0)]
<simple.fib.Main.main||2: simple.fib.Fibonacci.fib(I)V|| - ||i123>
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a114
	String.CASE_INSENSITIVE_ORDER: o68
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	i123: [0,+inf)(2){0,+inf}
	a112([java.lang.String...]): length i123
	a114([java.io.ObjectStreamField|]): length iconst_0
	o68!: String$CaseInsensitiveComparator()
Relations: 

3:

<simple.fib.Fibonacci.fib||0: push 0||n: i123|| ->
java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a112(lv_0_0)]
<simple.fib.Main.main||2: simple.fib.Fibonacci.fib|| - ||i123>
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a114
	String.CASE_INSENSITIVE_ORDER: o68
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	i123: [0,+inf)(2){0,+inf}
	a112([java.lang.String...]): length i123
	a114([java.io.ObjectStreamField|]): length iconst_0
	o68!: String$CaseInsensitiveComparator()
Relations: 

4:

<simple.fib.Fibonacci.fib||1: store INT to i||n: i123||iconst_0>
java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a112(lv_0_0)]
<simple.fib.Main.main||2: simple.fib.Fibonacci.fib|| - ||i123>
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a114
	String.CASE_INSENSITIVE_ORDER: o68
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	i123: [0,+inf)(2){0,+inf}
	a112([java.lang.String...]): length i123
	a114([java.io.ObjectStreamField|]): length iconst_0
	o68!: String$CaseInsensitiveComparator()
Relations: 

5:

<simple.fib.Fibonacci.fib||2: push 1||n: i123, i: iconst_0|| ->
java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a112(lv_0_0)]
<simple.fib.Main.main||2: simple.fib.Fibonacci.fib|| - ||i123>
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a114
	String.CASE_INSENSITIVE_ORDER: o68
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	i123: [0,+inf)(2){0,+inf}
	a112([java.lang.String...]): length i123
	a114([java.io.ObjectStreamField|]): length iconst_0
	o68!: String$CaseInsensitiveComparator()
Relations: 

6:

<simple.fib.Fibonacci.fib||3: store INT to j||n: i123, i: iconst_0||iconst_1>
java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a112(lv_0_0)]
<simple.fib.Main.main||2: simple.fib.Fibonacci.fib|| - ||i123>
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a114
	String.CASE_INSENSITIVE_ORDER: o68
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	i123: [0,+inf)(2){0,+inf}
	a112([java.lang.String...]): length i123
	a114([java.io.ObjectStreamField|]): length iconst_0
	o68!: String$CaseInsensitiveComparator()
Relations: 

7:

<simple.fib.Fibonacci.fib||4: push 0||n: i123, i: iconst_0, j: iconst_1|| ->
java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a112(lv_0_0)]
<simple.fib.Main.main||2: simple.fib.Fibonacci.fib|| - ||i123>
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a114
	String.CASE_INSENSITIVE_ORDER: o68
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	i123: [0,+inf)(2){0,+inf}
	a112([java.lang.String...]): length i123
	a114([java.io.ObjectStreamField|]): length iconst_0
	o68!: String$CaseInsensitiveComparator()
Relations: 

8:

<simple.fib.Fibonacci.fib||5: store INT to t||n: i123, i: iconst_0, j: iconst_1||iconst_0>
java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a112(lv_0_0)]
<simple.fib.Main.main||2: simple.fib.Fibonacci.fib|| - ||i123>
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a114
	String.CASE_INSENSITIVE_ORDER: o68
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	i123: [0,+inf)(2){0,+inf}
	a112([java.lang.String...]): length i123
	a114([java.io.ObjectStreamField|]): length iconst_0
	o68!: String$CaseInsensitiveComparator()
Relations: 

9:

<simple.fib.Fibonacci.fib||6: load INT j||n: i123, i: iconst_0, j: iconst_1|| ->
java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a112(lv_0_0)]
<simple.fib.Main.main||2: simple.fib.Fibonacci.fib|| - ||i123>
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a114
	String.CASE_INSENSITIVE_ORDER: o68
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	i123: [0,+inf)(2){0,+inf}
	a112([java.lang.String...]): length i123
	a114([java.io.ObjectStreamField|]): length iconst_0
	o68!: String$CaseInsensitiveComparator()
Relations: 

Start state of loop:

<simple.fib.Fibonacci.fib||6: load INT j||n: i17, i: i33, j: i34|| ->
java.lang.String = serialPersistentFields, CASE_INSENSITIVE_ORDER
[a39(lv_0_0)]
<simple.fib.Main.main||2: simple.fib.Fibonacci.fib|| - ||i17>
	String.serialVersionUID: iconstLong_-6849794470754667710
	String.serialPersistentFields: a38
	String.CASE_INSENSITIVE_ORDER: o30
	String$CaseInsensitiveComparator.serialVersionUID: iconstLong_8575799808933029326
	RuntimeException.serialVersionUID: iconstLong_-7034897190745766939
	Exception.serialVersionUID: iconstLong_-3387516993124229948
	Throwable.serialVersionUID: iconstLong_-3042686055658047285
	a38([java.io.ObjectStreamField|]): length iconst_0
	o30!: String$CaseInsensitiveComparator()
	i17: [0,+inf)(2){0,+inf}
	i33: [0,+inf)(4){0,+inf}
	i34: [1,+inf)(4){0,+inf}
	a39([java.lang.String...]): length i17
Relations: i34>iconst_0, i33>=iconst_0

In the loop head node, references [i34, i17] were interesting.
By SMT, we could prove
((0 <= initial_i17 and 0 <= initial_i33 and 1 <= initial_i34) and (((path1_i37 = (path1_i34 + path1_i33) and path1_i17 = res_i17 and path1_i34 = res_i33 and path1_i37 = res_i34 and path1_i17 = initial_i17 and path1_i33 = initial_i33 and path1_i34 = initial_i34) and path1_i34 > path1_i17) and (res_i37 = (res_i34 + res_i33) and !res_i34 != res_i17)))
to be UNSAT. Consequently, the loop will not terminate.

(2) NO