Use a string literal that contains an embedded single-quote (') character in Android

The SQL standard specifies that single-quotes in strings are escaped by putting two single quotes in a row. 

Example:

INSERT INTO xyz VALUES('5 O''clock');

So use '' at the place of '. like

if(constraint.contains("'")) 
            constraint = constraint.replace("'", "''");

ContactsContract.Contacts.DISPLAY_NAME + " LIKE '"+constraint+"%'"