-C-O-N-C-E-P-T- Series : Java

Difference between using "" and toString() method for converting object value to String:

Case I - Using "":

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BigDecimal dec = new BigDecimal("1234567");
String str = "" + dec; // converting dec to String
System.out.println("str: "+str);

o/p:
str: 1234567
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BigDecimal dec = null;
String str = "" + dec; // converting dec to String
System.out.println("str: "+str);

o/p:
str: null
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Case II - Using toString() method:

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BigDecimal dec = new BigDecimal("1234567");
String str = null;

if( dec!=null ) {
str = dec.toString(); // converting dec to String
}

System.out.println("str: "+str);

o/p:
str: 1234567
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BigDecimal dec = null;
String str = null;

if( dec!=null ) {

str = dec.toString(); // converting dec to String

}

System.out.println("str: "+str);

o/p:
str: null
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In first case, we don't require null check, but doesn't has readability.
In second case, we require null check, but has readability.

Each one has its own ease of use.