"Hej, Amigo! Nog med att stöka! Här är dina uppgifter. De kommer att bli svårare än de tidigare, och de kommer säkerligen att förbättra din processor. Och det är verkligen något vi behöver. Om du stöter på svårigheter, kolla med dina kollegor. De kommer definitivt att hjälpa."
"Du har redan gjort allt? Tja, här är några övningar som är ännu svårare:"
20
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Java Core, nivå, lektion
Tracking changes
Read 2 file names from the console: file1 and file2.
Both files contain text, but file2 is an updated version of file1. Some of the lines are still the same.
You need to create a merged version of the lines by writing them to the lines list.
The ADDED and REMOVED labels can't be used consecutively—t
20
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Java Core, nivå, lektion
Your own FileWriter
Implement FileConsoleWriter's logic.
The FileConsoleWriter class must have a private FileWriter field called fileWriter.
The FileConsoleWriter class must have every constructor used to initialize fileWriter for writing.
The FileConsoleWriter class must have five write methods and one close method:
-
20
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Java Core, nivå, lektion
Introducing tags
Read from the console the name of a file containing HTML.
Example:
Info about Leela Leela Turanga
Supergirl
The main method's first parameter is a tag name. For example, "span".
Display all tags that match the speci
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Java Core, nivå, lektion
Calculating salaries
The first parameter of the main method is a file name.
Each line of the specified file has the following format:
name value
where [name] is a String and [value] is a double. [name] and [value] are separated by a space.
Find the sum of all the values for each name.
Display all the data, sorted by na
12
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Java Core, nivå, lektion
The richest
The first parameter of the main method is a file name.
Each line of the specified file has the following format:
name value
where [name] is a String and [value] is a double. [name] and [value] are separated by a space.
Find the sum of all the values for each name.
Display in alphabetical order the
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Java Core, nivå, lektion
John Johnson
The first parameter of the main method is a file name.
Each line of the specified file has the following format:
name month day year
where [name] is a String that can contain several words separated by spaces.
[month] is an int, [day] is an int, and [year] is an int.
The data is separated by spaces.
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Java Core, nivå, lektion
Searching for the right lines
Read a file name from the console.
Display all of the file's lines that contain only 2 words in the words list.
Close the streams.
Example: words contains the words A, B, and C
Lines:
C B A D // 3 words from words, rejected
A B A D // 3 words from words, rejected
D A D // 1 word from words, rejecte
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Java Core, nivå, lektion
Words with numbers
The main method's first parameter is file1 and the second is file2.
file1 contains lines with words separated by spaces.
Write to file2 all the words that contain numbers, for example, a1 or abc3d. Separate the words with spaces.
Close the streams.
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Java Core, nivå, lektion
Replacing numbers
1. In a static block, initialize map with (number, word) pairs from 0 to 12 inclusive.
For example, (0, "zero"), (1, "one"), (2, "two")
2. Read the file name from the console, and then read the contents of the file.
3. Use map to replace all of the numbers with words.
4. Display the result.
5. Close
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Java Core, nivå, lektion
Long words
The main method's first parameter is file1 and the second is file2.
file1 contains words separated by spaces.
Write to file2 a comma-separated list of words longer than 6 characters.
file2 should not end with a comma.
Close the streams.
Example output to file2:
lengthy,shortened,abbreviation
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Java Core, nivå, lektion
Mirror image
1. Read a file name from the console. Read the contents of the file.
2. For each line in the file:
2.1. reverse the order of all characters.
2.2. display the result.
3. Close the streams.
Example input file:
I'm a programmer.
Amigo
Example result:
.remmargorp a m'I
ogimA
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Java Core, nivå, lektion
Contextual advertising
Replace the System.out object in the main method with your own reader wrapper.
Your reader wrapper should display a contextual ad after every other call to println.
Call testString's existing printSomething() method.
Restore the System.out variable back to the original stream.
Ad text: "CodeGym - o
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Java Core, nivå, lektion
Correct the bug. Classes and interfaces
This program has just 1 logical error. Find and fix it.