How do you check if a string exists in a file Java?

How do you check if a string exists in a file Java?

? To check a string for the pattern, you can use the String. indexOf() method….how to check if a string exists in a file

  1. Read in the file, line by line.
  2. Check each line for the pattern.
  3. If you find the pattern, print the “found” message.
  4. At the end, if you never found it, print the “not found” message.

How do you search for a word in Java?

JAVA Program

  1. public class SearchStringEmp {
  2. public static void main(String[] args) {
  3. String strOrig = “Hello readers”;
  4. int intIndex = strOrig. indexOf(“Hello”);
  5. if(intIndex == – 1) {
  6. System. out. println(“Hello not found”);
  7. } else {
  8. System. out. println(“Found Hello at index “+ intIndex);

How do I search for a specific word in a large text file?

Search for specifc words in huge log files or txt files

  1. Open cmd/powershell.
  2. Navigate to the location of the log file.
  3. Type the command: type u*.log |find /i “word to search” >> c:tempoutput.txt.

How do I find a word in a string in Java?

The String is a sequence of characters and a class in Java. To find a word in the string, we are using indexOf() and contains() methods of String class. The indexOf() method is used to find an index of the specified substring in the present string.

How do you check if a directory contains a file Java?

To test to see if a file or directory exists, use the “ exists() ” method of the Java java. io. File class, as shown here: File tempFile = new File( “c:/temp/temp.

How do you check directory is exist or not in Java?

io. File. exists() is used to check whether a file or a directory exists or not. This method returns true if the file or directory specified by the abstract path name exists and false if it does not exist.

How do I search a text file?

In many applications, you can use the Ctrl + F shortcut keys to open the Find option. On an Apple running macOS, you can use Command + F to open the find option. Finding text in a Word document.

Is Java a directory or file?

The isDirectory() function is a part of File class in Java . This function determines whether the is a file or directory denoted by the abstract filename is Directory or not. The function returns true if the abstract file path is Directory else returns false. Parameters: This method does not accept any parameter.

How do I find the path in Java?


  1. Select Start, select Control Panel. double click System, and select the Advanced tab.
  2. Click Environment Variables.
  3. In the Edit System Variable (or New System Variable) window, specify the value of the PATH environment variable.

How to read string from user in Java?

ArgumentException: The path is a zero-length string,contains only white space,or one or more invalid characters as defined by InvalidPathChars.

  • ArgumentNullException: The path is null.
  • PathTooLongException: The specified path,file name,or both exceed the system-defined maximum length.
  • DirectoryNotFoundException: The specified path is invalid.
  • How to search for a special character in Java String?

    indexOf (char c) : It searches the index of specified character within a given string. It starts searching from beginning to the end of the string (from left to right) and returns the corresponding index if found otherwise returns -1. Note: If given string contains multiple occurrence of specified character then it returns index of only first occurrence of specified character.

    How do you scramble a string in Java?

    public class Shuffle { public static void main(String[] args) { Shuffle s = new Shuffle(); s.shuffle(“hello”); } public void shuffle(String input) { List characters = new ArrayList (); for(char c:input.toCharArray()) { characters.add(c); } StringBuilder output = new StringBuilder(input.length()); while(characters.size()!=0) { int randPicker = (int) (Math.random()*characters.size()); output.append(characters.remove(randPicker)); } System.out.println(output.toString

    How to access string in file by position in Java?

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