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 * 
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package com.google.refine.commands.expr;

import java.io.IOException;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.fasterxml.jackson.annotation.JsonProperty;

import com.google.refine.ProjectManager;
import com.google.refine.commands.Command;
import com.google.refine.preference.TopList;

public class GetStarredExpressionsCommand extends Command {

    protected static class Expression {

        @JsonProperty("code")
        protected String code;

        protected Expression(String c) {
            code = c;
        }
    }

    protected static class ExpressionList {

        @JsonProperty("expressions")
        protected List<Expression> expressions;

        protected ExpressionList(List<Expression> e) {
            expressions = e;
        }
    }

    public static ExpressionList getExpressionsList() {
        TopList topList = (TopList) ProjectManager.singleton.getPreferenceStore().get("scripting.starred-expressions");
        List<String> starredExpressions = topList == null ? Collections.emptyList() : topList.getList();
        return new ExpressionList(starredExpressions.stream().map(e -> new Expression(e)).collect(Collectors.toList()));
    }

    @Override
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        try {
            respondJSON(response, getExpressionsList());
        } catch (Exception e) {
            respondException(response, e);
        }
    }
}
