Is there an effective way to convert java map values to comma separated string using guava or StringUtils?
有没有一种有效的方法可以使用guava或StringUtils将Java映射值转换为逗号分隔的字符串?
Map<String, String> testMap = new HashMap<>();
testMap.put("key1", "val1");
testMap.put("key2", "val2");
looking for a way to convert testMap to a String -> "val1,val2".
寻找将testMap转换为String的方法 - >“val1,val2”。
7 个解决方案
#1
11
Here's how to do it in Java 8 (doesn't require Guava, StringUtils, or other external libraries):
以下是如何在Java 8中执行此操作(不需要Guava,StringUtils或其他外部库):
testMap.values().stream().map(Object::toString).collect(Collectors.joining(","));
#2
9
Guava: Joiner.on(',').join(map.values())
.
Guava:Joiner.on(',')。join(map.values())。
#3
2
You can use StringUtils
:
您可以使用StringUtils:
final Map<String, String> testMap = new LinkedHashMap<String, String>();
testMap.put("key1", "val1");
testMap.put("key2", "val2");
String csv = StringUtils.join(testMap.values(), ',')); // "val1,val2"
Note that I changed the HashMap
to a LinkedHashMap
, in order to keep the insertion order.
请注意,我将HashMap更改为LinkedHashMap,以保持插入顺序。
#4
1
OK, here's my guess in case you want something like this (there's no clarification in your Question). This is done without Guava or StringUtils:
好的,这是我的猜测,以防你想要这样的事情(你的问题没有澄清)。这是在没有Guava或StringUtils的情况下完成的:
Map<Integer, Integer> map = new HashMap<Integer, Integer>();
map.put(1, 2);
map.put(3, 4);
System.out.println(map.toString());
Output:
输出:
{1=2, 3=4}
If you want to display the values
as a comma separated list, you could use this:
如果要将值显示为以逗号分隔的列表,可以使用以下命令:
System.out.println(map.values().toString());
Output:
输出:
[2, 4]
PS: Remove the []
s with .replaceAll()
if you want
PS:如果需要,可以使用.replaceAll()删除[]
#5
1
You can use makeString()
in Eclipse Collections.
您可以在Eclipse集合中使用makeString()。
MutableMap<String, String> testMap = new UnifiedMap<String, String>();
testMap.put("key1", "val1");
testMap.put("key2", "val2");
String commaAndSpace = testMap.makeString();
Assert.assertTrue(commaAndSpace.equals("val1, val2")
|| commaAndSpace.equals("val2, val1"));
String comma = testMap.makeString(",");
Assert.assertTrue(comma.equals("val1,val2")
|| comma.equals("val2,val1"));
If you cannot convert your Map
to an Eclipse Collections type, you can use MapAdapter
.
如果无法将Map转换为Eclipse Collections类型,则可以使用MapAdapter。
MapAdapter.adapt(testMap).makeString();
Note: I am a committer for Eclipse collections.
注意:我是Eclipse集合的提交者。
#6
0
If you are using spring MVC then this might work for you.
如果您使用的是Spring MVC,那么这可能对您有用。
import org.springframework.util.StringUtils;
Map<String, String> groups = //List of Maps
List<String> targetList = new ArrayList<String>(groups).values());
String csv = StringUtils.arrayToCommaDelimitedString(targetList.toArray());
Output: abc,def,ghi
输出:abc,def,ghi
#7
0
Map
has a function values()
to get all values. map.values() are string type so pass to string joiner. Example:
Map有一个函数values()来获取所有值。 map.values()是字符串类型,因此传递给字符串joiner。例:
Map<String, String> testMap = new HashMap<>();
testMap.put("key1", "val1");
testMap.put("key2", "val2");
String valueString = String.join(",",map.values()); //val1,val2
#1
11
Here's how to do it in Java 8 (doesn't require Guava, StringUtils, or other external libraries):
以下是如何在Java 8中执行此操作(不需要Guava,StringUtils或其他外部库):
testMap.values().stream().map(Object::toString).collect(Collectors.joining(","));
#2
9
Guava: Joiner.on(',').join(map.values())
.
Guava:Joiner.on(',')。join(map.values())。
#3
2
You can use StringUtils
:
您可以使用StringUtils:
final Map<String, String> testMap = new LinkedHashMap<String, String>();
testMap.put("key1", "val1");
testMap.put("key2", "val2");
String csv = StringUtils.join(testMap.values(), ',')); // "val1,val2"
Note that I changed the HashMap
to a LinkedHashMap
, in order to keep the insertion order.
请注意,我将HashMap更改为LinkedHashMap,以保持插入顺序。
#4
1
OK, here's my guess in case you want something like this (there's no clarification in your Question). This is done without Guava or StringUtils:
好的,这是我的猜测,以防你想要这样的事情(你的问题没有澄清)。这是在没有Guava或StringUtils的情况下完成的:
Map<Integer, Integer> map = new HashMap<Integer, Integer>();
map.put(1, 2);
map.put(3, 4);
System.out.println(map.toString());
Output:
输出:
{1=2, 3=4}
If you want to display the values
as a comma separated list, you could use this:
如果要将值显示为以逗号分隔的列表,可以使用以下命令:
System.out.println(map.values().toString());
Output:
输出:
[2, 4]
PS: Remove the []
s with .replaceAll()
if you want
PS:如果需要,可以使用.replaceAll()删除[]
#5
1
You can use makeString()
in Eclipse Collections.
您可以在Eclipse集合中使用makeString()。
MutableMap<String, String> testMap = new UnifiedMap<String, String>();
testMap.put("key1", "val1");
testMap.put("key2", "val2");
String commaAndSpace = testMap.makeString();
Assert.assertTrue(commaAndSpace.equals("val1, val2")
|| commaAndSpace.equals("val2, val1"));
String comma = testMap.makeString(",");
Assert.assertTrue(comma.equals("val1,val2")
|| comma.equals("val2,val1"));
If you cannot convert your Map
to an Eclipse Collections type, you can use MapAdapter
.
如果无法将Map转换为Eclipse Collections类型,则可以使用MapAdapter。
MapAdapter.adapt(testMap).makeString();
Note: I am a committer for Eclipse collections.
注意:我是Eclipse集合的提交者。
#6
0
If you are using spring MVC then this might work for you.
如果您使用的是Spring MVC,那么这可能对您有用。
import org.springframework.util.StringUtils;
Map<String, String> groups = //List of Maps
List<String> targetList = new ArrayList<String>(groups).values());
String csv = StringUtils.arrayToCommaDelimitedString(targetList.toArray());
Output: abc,def,ghi
输出:abc,def,ghi
#7
0
Map
has a function values()
to get all values. map.values() are string type so pass to string joiner. Example:
Map有一个函数values()来获取所有值。 map.values()是字符串类型,因此传递给字符串joiner。例:
Map<String, String> testMap = new HashMap<>();
testMap.put("key1", "val1");
testMap.put("key2", "val2");
String valueString = String.join(",",map.values()); //val1,val2