String StringBuilder Arrays ArrayList Miscellaneous
100
What is the equals() method?
This is the method used to compare two Strings.
100
What is 'append()'?
For classes that haven't overridden the toString method, this StringBuilder method appends the output from the default implementation of method toString defined in class Object.
100
What is contiguous/continuous memory?
Array member access offers improved access speed because of this memory layout.
100
What is 'java.util'?
The package for this class.
100
What is the diamond operator?
The name of the operator on the right where you were previously required to specify the data type.

ArrayList mylist = new ArrayList<>();
200
What is 'immutable'?
Since Java Strings cannot be changed, we call them this.
200
What is something that doesn't exist?
The trim() method of StringBuilder.
200
What are primitive and object data types?
These are the two types of data that an array can store.
200
What is an Object array?
This is the underlying data type used to store the data of the ArrayList.
200
What is 'creates a new length of the same size and copies the references of the values to the new array'?
Calling toArray() on an ArrayList does this to return the appropriate object.
300
What is the 'new' operator?
String objects created using this operator always refer to separate objects, even if they store the same sequence of characters.
300
What is 'subSequence()'?
This method is used to return a CharSequence that represents a substring of the StringBuilder value.
300
What is 'int'?
The data type used to specify the size of a dimension of an array.
300
What is the enhanced for loop?
The one iteration method that cannot be used if you are removing items from an ArrayList.
300
What is 'the comparison of the reference of the two objects'?
This is the default implementation of the equals() method of Object.
400
What is 'null'?
The literal value for String.
400
What are:
1. The position insertion point
2. The char[] to be inserted
3. The starting position in the char[]
4. The length to be copied from the char[]
?
The names of the arguments of this StringBuilder method call:

StringBuilder sb = new StringBuilder("123");
char[] name = {'J', 'a', 'v', 'a'};
sb.insert(1, name, 1, 3);
400
What is ArrayIndexOutOfBoundsException?
The error thrown when you attempt to access a nonexistent array index position.
400
What is 'clear()'?
Use this method to remove all elements of an ArrayList.
400
What is 'public boolean equals(Object object)'?
This is the method signature of the equals() method.
500
What are the 'start position' and the 'end position'?
The two arguments of the String.substring() method.
500
What is 'StringBuffer'?
The thread-safe version of StringBuilder.
500
What is 'length()'?
This method returns the number of components of the array.
500
What is 'true'?
An ArrayList can contain duplicate values. (T/F)
500
What is a shallow copy?
Cloning an ArrayList performs this type of copy.






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