overwrite a value inside a file in java -

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i create matrix of integers inside file using this,and want overwrite value after creating it,this code:

    import java.io.file; import java.io.filewriter;  public class main {     public static void main(string[] args) {     file file = new file("foo/file.txt");     filewriter writer = null;     try {         file.createnewfile();         writer = new filewriter(file);         (int = 0; < 5; i++) {         (int j = 0; j < 5; j++) {              writer.write(string.valueof(0) + " ");          }         writer.write("\n");         }     } catch (exception e) {         e.printstacktrace();     }     try {         (int = 0; < 5; i++) {         (int j = 0; j < 5; j++) {             if (i == 3)             writer.write(string.valueof(1) + " ");          }         }         writer.close();     } catch (exception e) {         e.printstacktrace();     }      } }

any suggestions? thanks.

sadly there no way replace 1 value in normal file situation. need form of reading in writing on file.

a best practice in java in scenario store contents in data structure. should use type of matrix in case, array of arrays 

int[][] values = new int[x][y];

once created reading file in, need write file same code.

if memory becomes issue, might need stream reading , writing use of temporary file.

i hope helps!


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