SCJP題庫第078題

A developer is creating a class Book, that needs to access class Paper. The Paper class is deployed in a JAR named myLib.jar. Which three, taken independently, will allow the developer to use the Paper class while compiling the Book class? (Choose Three.)

A. The JAR file is located at $JAVA_HOME/jre/classes/myLib.jar.

B. The JAR file is located at $JAVA_HOME/jre/lib/ext/myLib.jar.

C. The JAR file is located at /foo/myLib.jar and a classpath environment variable is set that includes /foo/myLib.jar/Paper.class.

D. The JAR file is located at /foo/myLib.jar and a classpath environment variable is set that includes /foo/myLib.jar.

E. The JAR file is located at /foo/myLib.jar and the Book class is compiled using javac –cp /foo/myLib.jar/Paper Book.java

F. The JAR file is located at /foo/myLib.jar and the Book class is compiled using javac -d /foo/myLib.jar Book.java

G. The JAR file is located at foo/myLib.jar and the Book class is compiled using javac –classpath /foo/myLib.jar Book.java

 

Ans: BDG

 

解說:

一個程式發展者正在建立一個類別Book，這個類別必須存取類別Paper，類別Paper被佈署在一個名為myLib.jar的JAR檔案，下列那三個可以分別地被這個發展者用來使用類別Paper，在編譯類別Book時

$JAVA_HOME/jre/lib/ext是Java執行環境預設放置JAR檔的地方

若不是放在這個地方，就要配合classpath的設定或指定，如答案BDG