数组Array转成List的几种方法

数组->List (StringArrayTest.java)

import java.util.Arrays;
import java.util.List;
import java.util.ArrayList;

public class StringArrayTest
{
   public static void main(String[] args)
   {
      String[] words = {"ace", "boom", "crew", "dog", "eon"};

      List wordList = Arrays.asList(words);

      for (String e : wordList)
      {
         System.out.println(e);
      }
   }
}import java.util.Arrays;
import java.util.List;
import java.util.ArrayList;

public class StringArrayTest
{
   public static void main(String[] args)
   {
      String[] words = {"ace", "boom", "crew", "dog", "eon"};

      List wordList = Arrays.asList(words);

      for (String e : wordList)
      {
         System.out.println(e);
      }
   }
}

比较傻的做法
String[] words={...};
List<String> list = new ArrayList(words.length);
for(String e: words){
list.add(e);
}

collections method
import java.util.Collections;
List myList = new ArrayList();
String myStringArray= new String[]{"dsdsa","pipe","little"};
Collections.addAll(myList,myStringArray);


java list用法,去除字符串数组中重复值
import java.util.Arrays;
import java.util.List;
import java.util.LinkedList;

public class ArrayTest {
  
    public static List printMap1(String[] s) {
        List<String> list =  new LinkedList<String>();
        List<String> list2 = Arrays.asList(s);
        list.addAll(list2);
        return list;
      
    }
  
    public static String[] array_unique(String[] a) {
        // array_unique
        List<String> list = new LinkedList<String>();
        for(int i = 0; i < a.length; i++) {
            if(!list.contains(a[i])) {
                list.add(a[i]);
            }
        }
        return (String[])list.toArray(new String[list.size()]);
    }
  
    public static void main(String[] args) {
        String[] ar = {"dd","cc","ee","ff","gg","cc","ee"};
        String[] s = array_unique(ar);
        for(String aa : s) {
            System.out.println(aa);
        }
        List list3 = printMap1(ar);
        for(Object o : list3) {
            System.out.println(o);
        }
    }  
}
Integer 数组转成 int 数组
Integer[] objs  -> int[] iobjs
Commons-lang 项目中的 ArrayList 的 toPrimitive 支持做 Java 中所有原生类型的数据转换，包括 int/float/double/char/short/byte
import org.apache.commons.lang.ArrayUtils;

Integer[] objs = ....;
int[] iobjs = ArrayUtils.toPrimitive(objs);

使用 Arrays.copyOf 进行数组复制
import java.util.Arrays;

public class ArrayCopy {
  public static void main(String args[]) {
    System.out.printf("Before (original)\t%s%n", Arrays.toString(args));
    String copy[] = Arrays.copyOf(args, 4);
    System.out.printf("Before (copy)\t\t%s%n", Arrays.toString(copy));
    copy[0] = "A";
    copy[1] = "B";
    copy[2] = "C";
    copy[3] = "D";
    System.out.printf("After (original)\t%s%n", Arrays.toString(args));
    System.out.printf("After (copy)\t\t%s%n", Arrays.toString(copy));
  }
}

Java 删除字符串右边的空格
public static String rightTrim(String data)
{
if(data==null)
return null;

char[]arr=data.toCharArray();
char[] newArr=new char[1];
int pos=0;
//worst algorithm ever. but works!
for (int i = 0; i < arr.length; i++)
{
pos=(arr.length-1)-i;
// System.out.println("pos["+pos+"] i["+i+"] ["+arr[pos]+"]");
if(arr[pos]!=' ')
{
newArr= new char[pos+1];
System.arraycopy(arr, 0, newArr, 0, pos+1);
break;
}

}

return new String(newArr);
}