Mixing
How to convert String back to Object List in Java
0
How to convert the string back to object? I have the following class:
class Test {
String name;
String value;
String testing;
@Override
public String toString() {
return "Test{" +
"name='" + name + ''' +
", value='" + value + ''' +
", testing='" + testing + ''' +
'}';
}
}
class Testing {
private List<Test> testing = new ArrayList<Test>();
handling(testing.toString())
public String handling(String testing) {
// do some handling and return a string
}
}
ArrayList testing must handled by convert to string, for example, after that, we get the following string:
[Test{name='name1', value='value1', testing='testing1'}, Test{name='name2', value='value2', testing='testing2'}, Test{name='name3', value='value3', testing='testing3'}]
then how to convert the string back to object list of Test?
Can anyone help on it?
java string list
asked Nov 19 '18 at 13:36
ratzip
4571721
add a comment |
0
How to convert the string back to object? I have the following class:
class Test {
String name;
String value;
String testing;
@Override
public String toString() {
return "Test{" +
"name='" + name + ''' +
", value='" + value + ''' +
", testing='" + testing + ''' +
'}';
}
}
class Testing {
private List<Test> testing = new ArrayList<Test>();
handling(testing.toString())
public String handling(String testing) {
// do some handling and return a string
}
}
ArrayList testing must handled by convert to string, for example, after that, we get the following string:
[Test{name='name1', value='value1', testing='testing1'}, Test{name='name2', value='value2', testing='testing2'}, Test{name='name3', value='value3', testing='testing3'}]
then how to convert the string back to object list of Test?
Can anyone help on it?
java string list
asked Nov 19 '18 at 13:36
ratzip
4571721
Not sure why you really need this, since you have the originalList<Test>within scope, but you could always add a static utility method to yourTestclass that would de-serialize a givenStringrepresentation back into aTestinstance.
– Mena
Nov 19 '18 at 13:38
3
If this is for some kind of text-based api I'd recommend using JSON which is easier to parse especially since there are a lot of libraries for that. If you use your own custom text representation then you'll have to provide your own custom parser as well.
– Thomas
Nov 19 '18 at 13:43
2
You shouldn't use toString() to serialize your objects. Instead of this just use Jackson to serialize objects to JSON and back from JSON to POJO. You objects should implement Serializable for it.
– Vlad
Nov 19 '18 at 13:43
it is not Json actually
– ratzip
Nov 19 '18 at 13:44
No, it is not JSON, but it could/should be. Otherwise you have to write a parser for it yourself.
– tevemadar
Nov 19 '18 at 13:45
add a comment |
0
0
0
1
How to convert the string back to object? I have the following class:
class Test {
String name;
String value;
String testing;
@Override
public String toString() {
return "Test{" +
"name='" + name + ''' +
", value='" + value + ''' +
", testing='" + testing + ''' +
'}';
}
}
class Testing {
private List<Test> testing = new ArrayList<Test>();
handling(testing.toString())
public String handling(String testing) {
// do some handling and return a string
}
}
ArrayList testing must handled by convert to string, for example, after that, we get the following string:
[Test{name='name1', value='value1', testing='testing1'}, Test{name='name2', value='value2', testing='testing2'}, Test{name='name3', value='value3', testing='testing3'}]
then how to convert the string back to object list of Test?
Can anyone help on it?
java string list
asked Nov 19 '18 at 13:36
ratzip
4571721
How to convert the string back to object? I have the following class:
class Test {
String name;
String value;
String testing;
@Override
public String toString() {
return "Test{" +
"name='" + name + ''' +
", value='" + value + ''' +
", testing='" + testing + ''' +
'}';
}
}
class Testing {
private List<Test> testing = new ArrayList<Test>();
handling(testing.toString())
public String handling(String testing) {
// do some handling and return a string
}
}
ArrayList testing must handled by convert to string, for example, after that, we get the following string:
[Test{name='name1', value='value1', testing='testing1'}, Test{name='name2', value='value2', testing='testing2'}, Test{name='name3', value='value3', testing='testing3'}]
then how to convert the string back to object list of Test?
Can anyone help on it?
java string list
java string list
asked Nov 19 '18 at 13:36
ratzip
4571721
asked Nov 19 '18 at 13:36
ratzip
4571721
asked Nov 19 '18 at 13:36
ratzip
4571721
asked Nov 19 '18 at 13:36
ratzip
4571721
asked Nov 19 '18 at 13:36
ratzip
4571721
4571721
Not sure why you really need this, since you have the originalList<Test>within scope, but you could always add a static utility method to yourTestclass that would de-serialize a givenStringrepresentation back into aTestinstance.
– Mena
Nov 19 '18 at 13:38
3
If this is for some kind of text-based api I'd recommend using JSON which is easier to parse especially since there are a lot of libraries for that. If you use your own custom text representation then you'll have to provide your own custom parser as well.
– Thomas
Nov 19 '18 at 13:43
2
You shouldn't use toString() to serialize your objects. Instead of this just use Jackson to serialize objects to JSON and back from JSON to POJO. You objects should implement Serializable for it.
– Vlad
Nov 19 '18 at 13:43
it is not Json actually
– ratzip
Nov 19 '18 at 13:44
No, it is not JSON, but it could/should be. Otherwise you have to write a parser for it yourself.
– tevemadar
Nov 19 '18 at 13:45
add a comment |
Not sure why you really need this, since you have the originalList<Test>within scope, but you could always add a static utility method to yourTestclass that would de-serialize a givenStringrepresentation back into aTestinstance.
– Mena
Nov 19 '18 at 13:38
3
If this is for some kind of text-based api I'd recommend using JSON which is easier to parse especially since there are a lot of libraries for that. If you use your own custom text representation then you'll have to provide your own custom parser as well.
– Thomas
Nov 19 '18 at 13:43
2
You shouldn't use toString() to serialize your objects. Instead of this just use Jackson to serialize objects to JSON and back from JSON to POJO. You objects should implement Serializable for it.
– Vlad
Nov 19 '18 at 13:43
it is not Json actually
– ratzip
Nov 19 '18 at 13:44
No, it is not JSON, but it could/should be. Otherwise you have to write a parser for it yourself.
– tevemadar
Nov 19 '18 at 13:45
Not sure why you really need this, since you have the original
List<Test> within scope, but you could always add a static utility method to your Test class that would de-serialize a given String representation back into a Test instance.– Mena
Nov 19 '18 at 13:38
Not sure why you really need this, since you have the original
List<Test> within scope, but you could always add a static utility method to your Test class that would de-serialize a given String representation back into a Test instance.– Mena
Nov 19 '18 at 13:38
3
3
If this is for some kind of text-based api I'd recommend using JSON which is easier to parse especially since there are a lot of libraries for that. If you use your own custom text representation then you'll have to provide your own custom parser as well.
– Thomas
Nov 19 '18 at 13:43
If this is for some kind of text-based api I'd recommend using JSON which is easier to parse especially since there are a lot of libraries for that. If you use your own custom text representation then you'll have to provide your own custom parser as well.
– Thomas
Nov 19 '18 at 13:43
2
2
You shouldn't use toString() to serialize your objects. Instead of this just use Jackson to serialize objects to JSON and back from JSON to POJO. You objects should implement Serializable for it.
– Vlad
Nov 19 '18 at 13:43
You shouldn't use toString() to serialize your objects. Instead of this just use Jackson to serialize objects to JSON and back from JSON to POJO. You objects should implement Serializable for it.
– Vlad
Nov 19 '18 at 13:43
it is not Json actually
– ratzip
Nov 19 '18 at 13:44
it is not Json actually
– ratzip
Nov 19 '18 at 13:44
No, it is not JSON, but it could/should be. Otherwise you have to write a parser for it yourself.
– tevemadar
Nov 19 '18 at 13:45
No, it is not JSON, but it could/should be. Otherwise you have to write a parser for it yourself.
– tevemadar
Nov 19 '18 at 13:45
add a comment |
2 Answers
2
active
oldest
votes
1
If you don't need exactly that toString pattern, but only need to convert your Object to something human-readable and than back to an Object, you could marshal to json and parse back to Object seamlessly with something like Jackson ObjectMapper. See https://www.baeldung.com/jackson-object-mapper-tutorial for a quick-start.
answered Nov 19 '18 at 13:45
Davide
1125
add a comment |
0
You can create an additional constructor and call them with the string:
class Test {
private String name;
private String value;
private String testing;
Test(string objString) {
Pattern pattern = Pattern.compile("name=('.+'), value=('.+), testing=('.+')");
Matcher matcher = pattern.matcher(objString);
if (matcher.matches()) {
name = matcher.group(1);
value = matcher.group(2);
testing = matcher.group(3);
} else {
throw new ArgumentException("Cannot parse""):
}
}
@Override
public String toString() {
return "Test{" +
"name='" + name + ''' +
", value='" + value + ''' +
", testing='" + testing + ''' +
'}';
}
}
class Testing {
doTesting(List<Test> testing) {
List<String> testingAsString = new ArrayList<String>();
// To string
for (Test t : testing) {
testingAsString.add(t.toString());
}
List<Test> clonedTesting = new ArrayList<Test>();
// To Test
for (String t : testingAsString) {
clonedTesting.add(new Test(t));
}
// Here every test string is again an object of type Test
for (Test t : clonedTesting) {
System.out.println(t);
}
}
}
answered Nov 19 '18 at 13:51
Kevin Wallis
3,07031533
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
1
If you don't need exactly that toString pattern, but only need to convert your Object to something human-readable and than back to an Object, you could marshal to json and parse back to Object seamlessly with something like Jackson ObjectMapper. See https://www.baeldung.com/jackson-object-mapper-tutorial for a quick-start.
answered Nov 19 '18 at 13:45
Davide
1125
add a comment |
1
If you don't need exactly that toString pattern, but only need to convert your Object to something human-readable and than back to an Object, you could marshal to json and parse back to Object seamlessly with something like Jackson ObjectMapper. See https://www.baeldung.com/jackson-object-mapper-tutorial for a quick-start.
answered Nov 19 '18 at 13:45
Davide
1125
add a comment |
1
1
1
If you don't need exactly that toString pattern, but only need to convert your Object to something human-readable and than back to an Object, you could marshal to json and parse back to Object seamlessly with something like Jackson ObjectMapper. See https://www.baeldung.com/jackson-object-mapper-tutorial for a quick-start.
answered Nov 19 '18 at 13:45
Davide
1125
If you don't need exactly that toString pattern, but only need to convert your Object to something human-readable and than back to an Object, you could marshal to json and parse back to Object seamlessly with something like Jackson ObjectMapper. See https://www.baeldung.com/jackson-object-mapper-tutorial for a quick-start.
answered Nov 19 '18 at 13:45
Davide
1125
answered Nov 19 '18 at 13:45
Davide
1125
answered Nov 19 '18 at 13:45
Davide
1125
answered Nov 19 '18 at 13:45
Davide
1125
1125
add a comment |
add a comment |
0
You can create an additional constructor and call them with the string:
class Test {
private String name;
private String value;
private String testing;
Test(string objString) {
Pattern pattern = Pattern.compile("name=('.+'), value=('.+), testing=('.+')");
Matcher matcher = pattern.matcher(objString);
if (matcher.matches()) {
name = matcher.group(1);
value = matcher.group(2);
testing = matcher.group(3);
} else {
throw new ArgumentException("Cannot parse""):
}
}
@Override
public String toString() {
return "Test{" +
"name='" + name + ''' +
", value='" + value + ''' +
", testing='" + testing + ''' +
'}';
}
}
class Testing {
doTesting(List<Test> testing) {
List<String> testingAsString = new ArrayList<String>();
// To string
for (Test t : testing) {
testingAsString.add(t.toString());
}
List<Test> clonedTesting = new ArrayList<Test>();
// To Test
for (String t : testingAsString) {
clonedTesting.add(new Test(t));
}
// Here every test string is again an object of type Test
for (Test t : clonedTesting) {
System.out.println(t);
}
}
}
answered Nov 19 '18 at 13:51
Kevin Wallis
3,07031533
add a comment |
0
You can create an additional constructor and call them with the string:
class Test {
private String name;
private String value;
private String testing;
Test(string objString) {
Pattern pattern = Pattern.compile("name=('.+'), value=('.+), testing=('.+')");
Matcher matcher = pattern.matcher(objString);
if (matcher.matches()) {
name = matcher.group(1);
value = matcher.group(2);
testing = matcher.group(3);
} else {
throw new ArgumentException("Cannot parse""):
}
}
@Override
public String toString() {
return "Test{" +
"name='" + name + ''' +
", value='" + value + ''' +
", testing='" + testing + ''' +
'}';
}
}
class Testing {
doTesting(List<Test> testing) {
List<String> testingAsString = new ArrayList<String>();
// To string
for (Test t : testing) {
testingAsString.add(t.toString());
}
List<Test> clonedTesting = new ArrayList<Test>();
// To Test
for (String t : testingAsString) {
clonedTesting.add(new Test(t));
}
// Here every test string is again an object of type Test
for (Test t : clonedTesting) {
System.out.println(t);
}
}
}
answered Nov 19 '18 at 13:51
Kevin Wallis
3,07031533
add a comment |
0
0
0
You can create an additional constructor and call them with the string:
class Test {
private String name;
private String value;
private String testing;
Test(string objString) {
Pattern pattern = Pattern.compile("name=('.+'), value=('.+), testing=('.+')");
Matcher matcher = pattern.matcher(objString);
if (matcher.matches()) {
name = matcher.group(1);
value = matcher.group(2);
testing = matcher.group(3);
} else {
throw new ArgumentException("Cannot parse""):
}
}
@Override
public String toString() {
return "Test{" +
"name='" + name + ''' +
", value='" + value + ''' +
", testing='" + testing + ''' +
'}';
}
}
class Testing {
doTesting(List<Test> testing) {
List<String> testingAsString = new ArrayList<String>();
// To string
for (Test t : testing) {
testingAsString.add(t.toString());
}
List<Test> clonedTesting = new ArrayList<Test>();
// To Test
for (String t : testingAsString) {
clonedTesting.add(new Test(t));
}
// Here every test string is again an object of type Test
for (Test t : clonedTesting) {
System.out.println(t);
}
}
}
answered Nov 19 '18 at 13:51
Kevin Wallis
3,07031533
You can create an additional constructor and call them with the string:
class Test {
private String name;
private String value;
private String testing;
Test(string objString) {
Pattern pattern = Pattern.compile("name=('.+'), value=('.+), testing=('.+')");
Matcher matcher = pattern.matcher(objString);
if (matcher.matches()) {
name = matcher.group(1);
value = matcher.group(2);
testing = matcher.group(3);
} else {
throw new ArgumentException("Cannot parse""):
}
}
@Override
public String toString() {
return "Test{" +
"name='" + name + ''' +
", value='" + value + ''' +
", testing='" + testing + ''' +
'}';
}
}
class Testing {
doTesting(List<Test> testing) {
List<String> testingAsString = new ArrayList<String>();
// To string
for (Test t : testing) {
testingAsString.add(t.toString());
}
List<Test> clonedTesting = new ArrayList<Test>();
// To Test
for (String t : testingAsString) {
clonedTesting.add(new Test(t));
}
// Here every test string is again an object of type Test
for (Test t : clonedTesting) {
System.out.println(t);
}
}
}
answered Nov 19 '18 at 13:51
Kevin Wallis
3,07031533
edited Nov 19 '18 at 13:57
answered Nov 19 '18 at 13:51
Kevin Wallis
3,07031533
answered Nov 19 '18 at 13:51
Kevin Wallis
3,07031533
answered Nov 19 '18 at 13:51
Kevin Wallis
3,07031533
3,07031533
add a comment |
add a comment |
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Not sure why you really need this, since you have the original
List<Test>within scope, but you could always add a static utility method to yourTestclass that would de-serialize a givenStringrepresentation back into aTestinstance.– Mena
Nov 19 '18 at 13:38
3
If this is for some kind of text-based api I'd recommend using JSON which is easier to parse especially since there are a lot of libraries for that. If you use your own custom text representation then you'll have to provide your own custom parser as well.
– Thomas
Nov 19 '18 at 13:43
2
You shouldn't use toString() to serialize your objects. Instead of this just use Jackson to serialize objects to JSON and back from JSON to POJO. You objects should implement Serializable for it.
– Vlad
Nov 19 '18 at 13:43
it is not Json actually
– ratzip
Nov 19 '18 at 13:44
No, it is not JSON, but it could/should be. Otherwise you have to write a parser for it yourself.
– tevemadar
Nov 19 '18 at 13:45