Google charts JSON无效

Question

下面的代码为Google图表返回json

public static DataTable generateDataTable(){
        // Create a data table,
        DataTable data = new DataTable();
        ArrayList cd = new ArrayList();
        cd.add(new ColumnDescription("name", ValueType.TEXT, "Animal name"));
        cd.add(new ColumnDescription("link", ValueType.TEXT, "Link to wikipedia"));
        cd.add(new ColumnDescription("population", ValueType.NUMBER, "Population size"));
        cd.add(new ColumnDescription("vegeterian", ValueType.BOOLEAN, "Vegetarian?"));

        data.addColumns(cd);

        // Fill the data table.
        try {
          data.addRowFromValues("Aye-aye", "http://en.wikipedia.org/wiki/Aye-aye", 100, true);
          data.addRowFromValues("Sloth", "http://en.wikipedia.org/wiki/Sloth", 300, true);
          data.addRowFromValues("Leopard", "http://en.wikipedia.org/wiki/Leopard", 50, false);
          data.addRowFromValues("Tiger", "http://en.wikipedia.org/wiki/Tiger", 80, false);
        } catch (TypeMismatchException e) {
          System.out.println("Invalid type!");
        }


        return data;
}

public static void main(String []args){
    String json = JsonRenderer.renderDataTable(generateDataTable(), false, false).toString();
    System.out.println(json);
}

但是返回的JSON

{cols:[{id:'name',label:'Animal name',type:'string',pattern:''},{id:'link',label:'Link to wikipedia',type:'string',pattern:''},{id:'population',label:'Population size',type:'number',pattern:''},{id:'vegeterian',label:'Vegetarian?',type:'boolean',pattern:''}]}

粘贴到http://jsonlint.com/中时无效

另外，返回的json {id:'name',label:'Animal name',type:'string',**pattern:''**}中显示的模式值是什么

Answer 1

谢谢你们的帮助。

我用Jackson解决了这个问题，它可以引用未引用的关键字

import org.codehaus.jackson.JsonFactory;
import org.codehaus.jackson.JsonNode;
import org.codehaus.jackson.JsonParser;  

JsonNode root = null;
String json = JsonRenderer.renderDataTable(generateDataTable(), true, false).toString();

        try{
            JsonParser parser = new JsonFactory().createJsonParser(json)
                .enable(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES)
                .enable(JsonParser.Feature.ALLOW_SINGLE_QUOTES);
                 root = new ObjectMapper().readTree(parser);
            }catch(Exception e){
                logger.error(e.getMessage());
            }

        response.getWriter().println(root.toString());

Answer 2

Google发送给您的是JavaScript object而不是JSON。

您需要找出一种将JavaScript object stringfy到JSON的方法。

看看this问题的答案。这可能会对你有帮助。