java中如何将字符串数组转换成字符串（转）

String[] str = {"abc", "bcd", "def"};
StringBuffer sb = new StringBuffer();
for(int i = 0; i < str.length; i++){
 sb. append(str[i]);
}
String s = sb.toString();

char[]   data={‘a‘,‘b‘,‘c‘};   
String  s=new   String(data);

String[] s = {"a","b","c"};
List list= java.util.Arrays.asList(s);

List<String> list = new ArrayList<String>();
list.add("a1");
list.add("a2");
String[] toBeStored = list.toArray(new String[list.size()]);
for(String s : toBeStored) {
System.out.println(s);
} 

List<String> list = new ArrayList<String>();
list.add("a1");
list.add("a2");

String[] toBeStored = new String[al.size()];
list.toArray(toBeStored);
for (String s : toBeStored) {
System.out.println(s);
} 

List<String> list = new ArrayList<String>();
list.add("a1");
list.add("a2");

String[] toBeStored = new String[]{};
String[] str = al.toArray(toBeStored);
for (String s : str) {
System.out.println(s);
}