init

linter/BlankPrintlnCheck.java

@@ -0,0 +1,19 @@
+// Nik Johnson
+// 2-24-2024
+// TA: Andy Ruan
+
+import java.util.*;
+
+// checks lines for the characters "System.out.println("")"
+public class BlankPrintlnCheck implements Check {
+
+    // if the line being checked has a blank println statement, return a new error (code 3)
+    // takes line and line number
+    // returns error inside optional 
+    public Optional<Error> lint(String line, int lineNumber) {
+        if (line.contains("System.out.println(\"\")")) {
+            return Optional.of(new Error(3, lineNumber, "Line contains blank print statement"));
+        }
+        return Optional.empty();
+    }
+}

linter/BreakCheck.java

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+// Nik Johnson
+// 2-24-2024
+// TA: Andy Ruan
+
+import java.util.*;
+
+// checks Strings for the characters "break" that come BEFORE the characters "//"
+public class BreakCheck implements Check {
+    
+    // if the line being checked has "break" in it 
+    // after removing all single line comments, return a new error (code 2)
+    // takes line and line number
+    // returns error inside optional
+    public Optional<Error> lint(String line, int lineNumber) {
+        String input = line;
+        String output = input.replaceAll("//.*", "");
+
+        if (output.contains("break")) {
+            return Optional.of(new Error(2, lineNumber, "we cant use break in this class bro"));
+        }
+        return Optional.empty();
+    }
+}

linter/Check.java

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+import java.util.*;
+
+// A common interface for linters that can check a single line of code
+// Every Check will check for its own type of error on a single line of code.
+public interface Check {
+	// Checks for this Check's error condition on this line with this line number.
+	// If an error exists on this line, returns an Optional with an Error present 
+	// indicating an error occurred. If no errors are present, returns an empty Optional.
+	public Optional<Error> lint(String line, int lineNumber);
+}
+

linter/Error.java

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+// Nik Johnson
+// 2-24-2024
+// TA: Andy Ruan
+
+/*
+Defining an object called Error, which has the fields:
+code: the errors code, represented by an int
+lineNumber: the line where the error occurred
+message: a description of the error
+*/
+public class Error {
+
+	private int code;
+	private int lineNumber;
+	private String message;
+
+	// construct an error with its fields
+	public Error(int code, int lineNumber, String message) {
+		this.code = code;
+		this.lineNumber = lineNumber;
+		this.message = message;
+	}
+
+	// format an error and its information nicely
+	public String toString() {
+		return ("(Line: " + lineNumber + ") " + "has error code " + code + "\n" + message);
+	}
+
+	// return line where the error occurs
+	public int getLineNumber() {
+		return this.lineNumber;
+	}
+
+	// return the error code (a number)
+	public int getCode() {
+		return this.code;
+	}
+
+	// return the errors description
+	public String getMessage() {
+		return this.message;
+	}
+}

linter/Linter.java

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+// Nik Johnson
+// 2-24-2024
+// TA: Andy Ruan
+
+import java.util.*;
+import java.io.*;
+
+// file-based linting object, linting based on checks defined in a list
+public class Linter {
+
+    private List<Check> checks;
+
+    // constructor, takes list of checks to perform
+    public Linter(List<Check> checks) {
+        this.checks = checks;
+    }
+
+    // compile list of errors based on output of check classes
+    // takes filename to perform checks on
+    // return list of errors present in that file
+    public List<Error> lint(String fileName) throws FileNotFoundException {
+        File toBeChecked = new File(fileName);
+        Scanner fileScanner = new Scanner(toBeChecked);
+        List<Error> errors = new ArrayList<>();
+        int lineNumber = 1;
+        while (fileScanner.hasNext()) {
+            String line = fileScanner.nextLine();
+            for (Check check : checks) {
+                Optional<Error> error = check.lint(line, lineNumber);
+                if (error.isPresent()) {
+                    errors.add(error.get());
+                }
+            }
+            lineNumber++;
+        }
+        fileScanner.close();
+        return errors;
+    }
+}

linter/LinterMain.java

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+// Nik Johnson
+// 2-24-2024
+// TA: Andy Ruan
+
+import java.util.*;
+import java.io.*;
+
+public class LinterMain {
+    public static final String FILE_NAME = "TestFile.txt";
+
+    public static void main(String[] args) throws FileNotFoundException {
+        List<Check> checks = new ArrayList<>();
+        checks.add(new LongLineCheck());
+        checks.add(new BreakCheck());
+        checks.add(new BlankPrintlnCheck());
+        Linter linter = new Linter(checks);
+        List<Error> errors = linter.lint(FILE_NAME);
+        for (Error e : errors) {
+            System.out.println(e);
+        }
+    }
+}

linter/LongLineCheck.java

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+// Nik Johnson
+// 2-24-2024
+// TA: Andy Ruan
+
+import java.util.*;
+
+// long line checker
+public class LongLineCheck implements Check {
+
+    // if the line being checked is 100 characters or longer, return a new error (code 1)
+    // takes line and line number
+    // returns error inside optional
+    public Optional<Error> lint(String line, int lineNumber) {
+        if (line.length() >= 100) {
+            return Optional.of(new Error(1, lineNumber, 
+            "Line length exceeded maximum length of 100 characters"));
+        }
+
+        return Optional.empty();
+    }
+}

linter/TestFile.java

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+public class TestFile {
+    public static void main(String[] args) {
+        System.out.println("This is a really really really long line that should fail the long line check");
+        while (true) {
+            System.out.println("");
+            break;
+        }
+        // break
+    }
+}

linter/TestFile.txt

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+package com.example;
+
+public class Example {
+    public static void main(String[] args) {
+        int x = 5;
+        while (x < 10) {
+            System.out.println("Hello, world!");
+            break;
+        }
+        for (int i = 0; i < 10; i++) {
+            if (i % 2 == 0) {
+                continue;
+            } else {
+                System.out.println(i);
+            }
+        }
+        try {
+            throw new Exception("Test");
+        } catch (Exception e) {
+            System.out.println("Caught an exception: " + e.getMessage());
+        } finally {
+            System.out.println("Finally block executed.");
+        }
+        for (int j = 0; j < 100; j++) {
+            if (j % 2 == 0) {
+                break;
+            } else {
+                System.out.println(j);
+            }
+        }
+        while (x > 5) {
+            System.out.println("Hello, world!");
+            break;
+        }
+        if (x % 2 == 0) {
+            continue;
+        } else {
+            System.out.println(x);
+        }
+        for (int k = 0; k < 1000; k++) {
+            if (k % 2 == 0) {
+                break;
+            } else {
+                System.out.println(k);
+            }
+        }
+        while (x > 5) {
+            System.out.println("Hello, world!");
+            break;
+        }
+        if (x % 2 == 0) {
+            continue;
+        } else {
+            System.out.println(x);
+        }
+        for (int l = 0; l < 10000; l++) {
+            if (l % 2 == 0) {
+                break;
+            } else {
+                System.out.println(l);
+            }
+        }
+        while (x > 5) {
+            System.out.println("Hello, world!");
+            break;
+        }
+        if (x % 2 == 0) {
+            continue;
+        } else {
+            System.out.println(x);
+        }
+        for (int m = 0; m < 100000; m++) {
+            if (m % 2 == 0) {
+                break;
+            } else {
+                System.out.println(m);
+            }
+        }
+        while (x > 5) {
+            System.out.println("Hello, world!");
+            break;
+        }
+        if (x % 2 == 0) {
+            continue;
+        } else {
+            System.out.println(x);
+        }
+    }
+}