Chapter 4: Arrays and Strings

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Chapter 4 Arrays and Strings
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Basics of Arrays

• Declaration int myArray or int myArray
• Definition int myArray new int10
• Accessing num myArrayi I should be int
• Array bound check!!!
• Reusing the array myArray new int100
• Initializing int myArray 1, 2, 3
• Array length myArray.length
• Examples MorePrimes.java WeatherFan.java
• Array of characters char vowels a, e,
  I, o, u

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Strings

• String Literals This is a string
• Declare String String myString
• Initialize String String myString My String
• Arrays of Strings String names new
  String5
• String concatenation JoinStrings.java
• String matching MatchStrings.java Identity!
• String comparison SequenceString.java
• String searching FindCharacters.java
• Extracting Strings ExtractSubstring.java

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StringBuffer Class

• It is a class that looks like the String class
  but it is not a static one
• Operations (concat., etc.) are much more
  efficient using StringBuffer
• Default capacity is 16 StringBuffer buffer new
  StringBuffer()
• length() and capacity() may vary
• To concatenate use append()
• To insert use insert() buf.insert(5, ttt)
• To convert to String object use toString()