CharSequence[]
に参照をキャストすることはできませんString[]
。
あなたはその状況でのみそれをキャストすることができます:
CharSequence[] charSequencesAsString = new String[] { "test" };
String[] result = (String[]) charSequencesAsString;
System.out.println(Arrays.toString(result));
問題を解決する安全な方法:
public static void main(String[] args) {
CharSequence[] charSequencesAsString = new String[] { "test" };
CharSequence[] charSequencesAsCharSequence = new CharSequence[] { "test" };
CharSequence[] charSequencesAsStringBuilder = new StringBuilder[] { new StringBuilder("Test") };
String[] stringsFromStrings = convertToStringArray(charSequencesAsString);
String[] stringsFromCharSequence = convertToStringArray(charSequencesAsCharSequence);
String[] stringsFromStringBuilder = convertToStringArray(charSequencesAsStringBuilder);
System.out.println("Same array after conversion: " + (stringsFromStrings == charSequencesAsString));
System.out.println("Same array after conversion: " + (stringsFromCharSequence == charSequencesAsCharSequence));
System.out.println("Same array after conversion: " + (stringsFromStringBuilder == charSequencesAsStringBuilder));
}
public static String[] convertToStringArray(CharSequence[] charSequences) {
if (charSequences instanceof String[]) {
return (String[]) charSequences;
}
String[] strings = new String[charSequences.length];
for (int index = 0; index < charSequences.length; index++) {
strings[index] = charSequences[index].toString();
}
return strings;
}