implementation level refactoring

[Vivek504]

Extract method refactoring

Class: org.apache.pdfbox.io.ScratchFile
Reason for refactoring: Complex method - Cyclomatic complexity of enlarge() method is 9.
Explanation of refactoring: Method is divided into multiple methods to reduce the cyclomatic complexity.

Decompose conditional refactoring

Class: org.apache.pdfbox.io.MemoryUsageSetting
Reason for refactoring: Complex Conditional - The conditional expression locUseMainMemory && (locMaxStorageBytes > -1) && ((locMaxMainMemoryBytes == -1) || (locMaxMainMemoryBytes > locMaxStorageBytes)) is complex.
Explanation of refactoring: Introduced new methods for conditional logic.

Introduce explaining variable refactoring

Class: org.apache.pdfbox.io.IOUtils
Reason for refactoring: Long Statement

1. The length of the statement "final MethodHandle nonNullTest=lookup.findStatic(Objects.class,"nonNull",methodType(boolean.class,Object.class)).asType(methodType(boolean.class,cleanerClass));" is 160.
2. The length of the statement "final MethodHandle unmapper=filterReturnValue(directBufferCleanerMethod,guardWithTest(nonNullTest,cleanMethod,noop)).asType(methodType(void.class,ByteBuffer.class));" is 165.

Explanation of refactoring: Complicated expressions are replaced by explaining variables.