summaryrefslogtreecommitdiff
path: root/src/main/FarmShell.java
blob: 82478ec6c3865f7d64a83719c7e5ca878802ed28 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

package main;

import java.io.IOException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Arrays;
import java.util.NoSuchElementException;
import java.util.Scanner;
import java.util.Set;

/**
 *
 * @author s123188
 */
public class FarmShell {
    
    private final Scanner scanner = new Scanner(System.in);
    
    Analyzor analyzor;
    
    /*
    private void printPrompt() {
        if (stream_cached == null) {
            // "dollars are worthless"
            System.out.print("$ ");
        } else if (stream_cached.isValid()) {
            // "we make money now by receiving tweets"
            System.out.print("€ ");
        } else {
            // "we previously made money, but not anymore"
            System.out.print("ƒ ");
        }
    }
*/
    /**
     * Processes commands from stdin until the exit command is received or EOF.
     */
    public void process_forever() {
        System.err.println("Entering interactive shell, type 'help' for help "
                + "or 'exit' to leave. '.' repeats the previous interactive "
                + "command.");
        // print prompt for reading first command
        //printPrompt();
        String lastLine = "";
        while (scanner.hasNextLine()) {
            String line = scanner.nextLine().trim();
            // repeat last command
            if (line.equals(".")) {
                line = lastLine;
            }
            if (!execute(line)) {
                // requested to terminate
                break;
            }
            if (!line.isEmpty()) {
                lastLine = line;
            }
            // print prompt for reading next line
            //printPrompt();
        }
        // prevent corrupted compressed files when exiting without a command
        throw new NoSuchElementException();
    }

    public boolean execute(String cmd) {
        String[] args = cmd.trim().split("\\s+", 2);
        if (!args[0].isEmpty()) {
            // non-empty command, let's see whether it makes sense?
            return execute(args);
        }
        return true;
    }

    /**
     * Executes a command with optional parameters.
     *
     * @param args An array with the first argument containing the command with
     * optional parameters in following arguments.
     * @return true if more commands are allowed to be executed, false
     * otherwise.
     */
    public boolean execute(String[] args) {
        //make a new Analyzor
        analyzor = new Analyzor();
        
        try {
            Command command = Command.fromString(args[0]);
            String[] params = Arrays.copyOfRange(args, 1, args.length);
            execute(command, params);
        } catch (IllegalArgumentException ex) {
            System.err.println(ex.getMessage());
        } catch (IOException ex) {
            System.err.println("Command " + args[0] + " failed with " + ex);
            ex.printStackTrace();
        } catch (NoSuchElementException ex) {
            // thrown by the "exit" command to signal exit
            return false;
        }
        // another satisfied customer, next!
        return true;
    }

    enum Command {
        
        query("make a query to the database; needed to do analysis", 1),
        filterbots("marks all users as bot or not"),
        sentiment("analyzes all tweets on positivity (about a brand)"),
        exit("Returns to shell"),
        help("Get help");

        private final String description;
        private final int paramCount;

        Command(String description) {
            this.description = description;
            this.paramCount = 0;
        }

        Command(String description, int paramCount) {
            this.description = description;
            this.paramCount = paramCount;
        }

        public String getDescription() {
            return description;
        }

        public int getParamCount() {
            return paramCount;
        }

        public static Command fromString(String command) {
            for (Command cmd : values()) {
                if (cmd.name().equals(command)) {
                    return cmd;
                }
            }
            throw new IllegalArgumentException("Unrecognized command. Hint: help");
        }
    };

    private final String[] HELP = new String[]{
        "Interactive TweetShell",
        "",
        "Available commands:"
    };

    private void execute(Command command, String[] params) throws IOException {
        if (params.length < command.getParamCount()) {
            throw new IllegalArgumentException("Expected "
                    + command.getParamCount() + " parameters, got only "
                    + params.length);
        }
        switch (command) {
            case query:
                analyzor.Query(params[0]);
                break;
            case filterbots:
                System.out.println("not yet implemented");
                break;
            case sentiment:
                analyzor.sentimentAnalysis();
                break;
            case help:
                for (String line : HELP) {
                    System.out.println(line);
                }
                for (Command cmd : Command.values()) {
                    System.out.printf("  %-10s", cmd.name());
                    if (!cmd.getDescription().isEmpty()) {
                        System.out.print(" " + cmd.getDescription());
                    }
                    if (cmd.getParamCount() == 1) {
                        System.out.print(" (1 arg)");
                    } else if (cmd.getParamCount() > 1) {
                        System.out.printf(" (%d args)", cmd.getParamCount());
                    }
                    System.out.println();
                }
                break;
            case exit:
                throw new NoSuchElementException();
            default:
                throw new AssertionError(command.name());
        }
    }
}