Oracle 1Z0-819 Certification Sample Questions and Answers

1Z0-819 PDF, 1Z0-819 Dumps PDF Free Download, 1Z0-819 Latest Dumps Free PDF, Java SE Developer PDF DumpsThe Oracle Java SE Developer (1Z0-819) Sample Question Set is designed to help you prepare for the Oracle Certified Professional - Java SE 11 Developer certification exam. To become familiar with the actual Oracle Certification exam environment, we suggest you try our Sample Oracle 1Z0-819 Certification Practice Exam.

This Oracle Java SE 11 Developer certification sample practice test and sample question set are designed for evaluation purposes only. If you want to test your Oracle 1Z0-819 knowledge to identify your areas of improvement and get familiar with the actual exam format, we suggest you prepare with the Premium Oracle Certified Professional - Java SE 11 Developer Certification Practice Exam. Our team of Oracle Java experts has designed Questions-Answers for this premium practice exam by collecting inputs from recently certified candidates. Our premium Oracle 1Z0-819 certification practice exam will boost your confidence as well as your actual Oracle Java SE Developer exam result.

Oracle 1Z0-819 Sample Questions:

01. To detect integer overflow when adding two int values in secure code, which approach is appropriate?
a) Use Math.addExact, which always throws on overflow.
b) Overflow does not happen with int in Java.
c) Cast both operands to short first.
d) Compare a + b > Integer.MAX_VALUE after the addition.
 
02. Files.deleteIfExists(path) is called on a path that does not exist.
What happens?
a) It throws IOException.
b) It throws NoSuchFileException.
c) It returns true.
d) It returns false and does not throw.
 
03. Which two module-info directives let ANOTHER module access this module's package types or members?
(Choose two.)
a) requires — declares a dependency on another module
b) requires transitive — re-exports a dependency
c) uses — consumes a service via ServiceLoader
d) exports — compile-time and run-time access to public types
e) opens — run-time reflective (deep) access
 
04. If ResourceBundle.getBundle("Msg") is called with no Locale argument, which locale is used?
a) Locale.ROOT is always used.
b) It throws because a locale is required.
c) Locale.getDefault(), the JVM default locale.
d) Locale.US is always used.
 
05. A developer calls con.setAutoCommit(false), runs two executeUpdate calls, then returns without calling commit.
What happens to the two updates?
a) They throw an SQLException immediately.
b) They stay uncommitted until commit is called.
c) They are committed after each executeUpdate.
d) They are committed automatically when the method returns.
 
06. What does Paths.get("/a/b").relativize(Paths.get("/a/b/c/d")) produce?
a) /a/b/c/d
b) ../../c/d
c) c/d
d) /a/b
 
07. new Locale("de").getDisplayLanguage(new Locale("fr")) returns the name of the German language expressed in French.
What kind of API is this?
a) A no-op that just returns "de".
b) A localization display-name lookup (it returns "allemand").
c) A currency-formatting call.
d) A compile error, because getDisplayLanguage takes no argument.
 
08. An object whose class does NOT implement Serializable is passed to ObjectOutputStream.writeObject.
When and what error occurs?
a) A ClassCastException.
b) Nothing — objects serialize by default.
c) A compile error.
d) A NotSerializableException is always thrown at runtime.
 
09. Why should exception messages and logs avoid raw sensitive data such as passwords, keys, or PII?
a) Logs may expose the data to lower-privilege viewers.
b) It measurably slows logging throughput.
c) Exceptions cannot carry String data.
d) Logging frameworks encrypt all output automatically.
 
10. Given String s1 = "hi"; String s2 = new String("hi");.
What are s1 == s2 and s1.equals(s2)?
a) Both are true.
b) Both are false.
c) s1 == s2 is true; s1.equals(s2) is false.
d) s1 == s2 is false; s1.equals(s2) is true.

Answers:

Question: 01

Answer: a

Question: 02

Answer: d

Question: 03

Answer: d, e

Question: 04

Answer: c

Question: 05

Answer: b

Question: 06

Answer: c

Question: 07

Answer: b

Question: 08

Answer: d

Question: 09

Answer: a

Question: 10

Answer: d

 

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