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How can I parse invalid JSON to Java Object using Pojo Class

I'm not sure what format this object is in but can I parse the following invalid JSON object to Java class Pojo? I tried doing it using Jackson but since it's invalid, I was wondering if pojo class would work?
{
name: (sindey, crosby)
game: "Hockey"
type: athlete
}
The file would have multiple objects of this format

Geesh, don't recognise this format! If you want to use Jackson you could pre-process you data to wrap the values... perhaps a regex to catpure the groups and wrap the values in quotes something like (name|type):\s(.+) => $1: "$2"
I was wondering if pojo class would work?
Sure, you could make that work with a simple parser; plenty of room for improvement, but something like this would do it:
Record record = null;
var records = new LinkedList<>();
// I'm using a reader as example, but just provide lines any way you like
while ((line = reader.readLine()) != null) {
line = line.trim();
// may need to skip empty lines if you have them in your file...
if (line.equals("{")) {
record = new Record();
records.add(record);
} else {
// may need substrings if your data contains ":"
var tokens = line.split(":");
var field = tokens[0];
var value = tokens[1];
if (field.equals("name")) {
// perhaps shuffle the format to something nicer here..
record.setName(value);
}
/// same for game and type fields...
}
}

Reading a csv file into an array in Java (the add method not working)

I am trying to implement a csv reader into my class in Java using eclipse. I keep getting an error for the add method "add(Person) in the type list is not applicable for the arguments (String[]). What am I doing wrong?
public static List<Person> readPersons(String fileName)
throws FileNotFoundException {
int count = 0;
List<Person[]> content = new ArrayList<>();
try(BufferedReader cv = new BufferedReader(new FileReader(fileName))){
String line = "";
while ((line = cv.readLine()) != null) {
content.add(line.split(","));
}
} catch (FileNotFoundException e) {
}
return content;
}
Also, how do I implement this FileNotFoundException extender? It is required in the program.

The line.split( "," ) method will return an array of strings.
What it does is: The original string line is split into an array of strings. In that array, every string is a substring of line which is separated by a comma.
For example, if line is "Peter,Smith,38", the following array of strings will be returned: [ "Peter", "Smith", "38" ].
But, since your List only can contain objects of the type Person, it cannot take the String[] array returned by line.split( "," ).
So assuming you have an Constructor for Person that looks like this: Person( String firstName, String secondName, int age ) you would have to change your while loop to something like this:
while ( ( line = cv.readLine( ) ) != null )
{
// Get the data from the CSV object
String[] csvData = line.split( "," );
// Create a Person object with the retrieved data
Person personFromCsvLine = new Person( csvData[0], csvData[1], Integer.parseInt( csvData[2] );
// Now you can add the person object to your list
content.add( personFromCsvLine );
}

The answer by be-ta is correct.
I would like to point out that for reading a CSV you might want to consider using an existing solution in your code, like:
Apache Commons CSV
Jackson CsvMapper
Example code
These libraries will help with quoted / unquoted columns and conversion of values to the proper datatypes.

How to write ArrayList<Object> to a csv file

I have a ArrayList<Metadata> and i want to know if there is a Java API for working with CSV files which has a write method which accepts a ArrayList<> as parameter similar to LinqToCsv in .Net. As i know OpenCSV is available but the CsvWriter class doesn't accept a collection.
My Metadata Class is
public class Metadata{
private String page;
private String document;
private String loan;
private String type;
}
ArrayList<Metadata> record = new ArrayList<Metadata>();
once i populate the record, i want to write each row into a csv file.
Please suggest.

Surely there'll be a heap of APIs that will do this for you, but why not do it yourself for such a simple case? It will save you a dependency, which is a good thing for any project of any size.
Create a toCsvRow() method in Metadata that joins the strings separated by a comma.
public String toCsvRow() {
return Stream.of(page, document, loan, type)
.map(value -> value.replaceAll("\"", "\"\""))
.map(value -> Stream.of("\"", ",").anyMatch(value::contains) ? "\"" + value + "\"" : value)
.collect(Collectors.joining(","));
}
Collect the result of this method for every Metadata object separated by a new line.
String recordAsCsv = record.stream()
.map(Metadata::toCsvRow)
.collect(Collectors.joining(System.getProperty("line.separator")));
EDIT
Should you not be so fortunate as to have Java 8 and the Stream API at your disposal, this would be almost as simple using a traditional List.
public String toCsvRow() {
String csvRow = "";
for (String value : Arrays.asList(page, document, loan, type)) {
String processed = value;
if (value.contains("\"") || value.contains(",")) {
processed = "\"" + value.replaceAll("\"", "\"\"") + "\"";
}
csvRow += "," + processed;
}
return csvRow.substring(1);
}

By using CSVWriter, you could convert the ArrayList to an array, and pass that to the writer .
csvWriter.writeNext(record.toArray(new String[record.size()]));

If you have an ArrayList of Objects (Metadata in your case) you would use the BeanToCSV instead of the CSVWriter.
You can look at the BeanToCSVTest in the opencsv source code for examples of how to use it.

How to replace a specific word from String in Java

How to replace "{{customer}}" from this string "Congrats {{customer}}, you become the potential winner of auction" with "xyz".
Thanks in advance,
Suggestion appreciated.

like this?
String string = "Congrats {{customer}}";
String newValue = string.replace("{{customer}}", "xyz");
// 'string' remains the same..but 'newValue' has the replacement.
System.out.println(newValue);

Use the replace method on the String object to do this. Since String is immutable it will return a new object instance with the replaced text. Example:
String myString = "Congrats {{customer}}";
myString = myString.replace("{{customer}}","John");
System.out.println(myString);
Output:
Congrats John
See also the String javadoc for many more useful utility methods.

That looks like a mustache template.
See https://github.com/spullara/mustache.java
Typically, in your case:
HashMap<String, Object> scopes = new HashMap<String, Object>();
scopes.put("customer", "xyz");
Writer writer = new OutputStreamWriter(System.out);
MustacheFactory mf = new DefaultMustacheFactory();
Mustache mustache = mf.compile(new StringReader("Congrats {{customer}}, you become the potential winner of auction"), "example");
mustache.execute(writer, scopes);
writer.flush();

Using resources, you can use method like this:
String customer = "Joe Doe";
String textHello;
textHello = String.format(getString(R.string.hello_customer), customer);
where hello_customer is your string resorce strings.xml.
strings.xml part should look like this:
<string name="hello_customer">Congrats %1$s, you become the potential winner of auction with \"xyz\".</string>

Is there a way to render a string like 'Hello, %(name)s' % {'name':'Felix'} in Java?

In Python we can do this easily:
data = {'name':'Felix'}
s = 'Hello, %(name)s' % data
s
'Hello, Felix'
Is there a similar way in Java to implement the same thing?
PS:
Sorry for the unclear question. the use case is : we have a map which stores the key-values, the Template only need to specify a key in the map, then the value of the key will be in the place where the key is in the template.

AFAIK you can use String#format for this:
String name = "Felix";
String s = String.format("Hello, %s", name);
System.out.println(s);
This will print
Hello, Felix
More info about how to use the formatting of String#format can be found on java.util.Formatter syntax

You want String.format method.
String data = "Hello, %s";
String updated = String.format(data, "Felix");

If you want to replace only Strings with Strings then code from second part of my answer will be better
Java Formatter class doesn't support %(key)s form, but instead you can use %index$s where index is counted from 1 like in this example
System.out.format("%3$s, %2$s, %1s", "a", "b", "c");
// indexes 1 2 3
output:
c, b, a
So all you need to do is create some array that will contain values used in pattern and change key names to its corresponding indexes (increased by 1 since first index used by Formatter is written as 1$ not as 0$ like we would expect for arrays indexes).
Here is example of method that will do it for you
// I made this Pattern static and put it outside of method to compile it only once,
// also it will match every (xxx) that has % before it, but wont include %
static Pattern formatPattern = Pattern.compile("(?<=%)\\(([^)]+)\\)");
public static String format(String pattern, Map<String, ?> map) {
StringBuffer sb = new StringBuffer();
List<Object> valuesList = new ArrayList<>();
Matcher m = formatPattern.matcher(pattern);
while (m.find()) {
String key = m.group(1);//group 1 contains part inside parenthesis
Object value = map.get(key);
// If map doesn't contain key, value will be null.
// If you want to react somehow to null value like throw some
// Exception
// now is the good time.
if (valuesList.contains(value)) {
m.appendReplacement(sb, (valuesList.indexOf(value) + 1) + "\\$");
} else {
valuesList.add(value);
m.appendReplacement(sb, valuesList.size() + "\\$");
}
}
m.appendTail(sb);
return String.format(sb.toString(), valuesList.toArray());
}
usage
Map<String, Object> map = new HashMap<>();
map.put("name", "Felix");
map.put("age", 70);
String myPattern =
"Hi %(emptyKey)s! My name is %(name)s %(name)s and I am %(age)s years old";
System.out.println(format(myPattern, map));
output:
Hi null! My name is Felix Felix and I am 70 years old
As you can see you can use same key few times (in our case name) and if your map wont contain key used in your String pattern (like emptyKey) it will be replaced with null.
Above version was meant to let you set type of data like s d and so on, but if your data will always be replaced with Strings, then you can skip String.format(sb.toString(), valuesList.toArray()) and replace all your keys with values earlier.
Here is simpler version that will accept only map with <String,String> key-value relationship.
static Pattern stringsPattern = Pattern.compile("%\\(([^)]+)\\)s\\b");
public static String formatStrings(String pattern, Map<String, String> map) {
StringBuffer sb = new StringBuffer();
Matcher m = stringsPattern.matcher(pattern);
while (m.find()) {
// we can't use null as replacement so we need to convert it to String
// first. We can do it with String.valueOf method
m.appendReplacement(sb, String.valueOf(map.get(m.group(1))));
}
m.appendTail(sb);
return sb.toString();
}

Under this use case, you need a template engine like velocity or freemarker to use a Map-like data structure to render a string template, there is no builtin module in java to do that. like this(with velocity):
public static void main(String[] args) {
Context context = new VelocityContext();
context.put("appid", "9876543d1");
context.put("ds", "2013-09-11");
StringWriter sw = new StringWriter();
String template = "APPID is ${appid} and DS is ${ds}";
Velocity.evaluate(context, sw, "velocity", template);
System.out.println(sw.toString());
}

If you want more advanced techniques like i18n support, you can use the advanced Message Format features
ex:
in langage properties files you add the property 'template' wich is your message
template = At {2,time,short} on {2,date,long}, \
we detected {1,number,integer} spaceships on \
the planet {0}.
then you can format your valriables pass the arguments in an array:
Object[] messageArguments = {
"Mars",
new Integer(7),
new Date()
};
You call the formatter it this way:
MessageFormat formatter = new MessageFormat("");
formatter.setLocale(currentLocale);
formatter.applyPattern(messages.getString("template"));
String output = formatter.format(messageArguments);
the detailed example is here
http://docs.oracle.com/javase/tutorial/i18n/format/messageFormat.html