3. string foo = “ABCDE”; 4. foo.substring(3); 5. foo.concat(“XYZ”); 6. Type the value of foo at line 6.()
5. String foo = “base”; 6. foo.substring(0,3); 7. foo.concat(“ket”) 8. Type the value of foo at line 8.()
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public class Delta { static boolean foo(char c) { System.out.print(c); return true; } public static void main( String[] argv ) { int i =0; for ( foo(‘A’); foo(‘B’)&&(i<2); foo(‘C’)){ i++ ; foo(‘D’); } } } What is the result?() A、 ABDCBDCBB、 ABCDABCDC、 Compilation fails.D、 An exception is thrown at runtime.
public class Test { public static void main(String args[]) { class Foo { public int i = 3; } Object o = (Object)new Foo(); Foo foo = (Foo)o; System.out.println(“i = “ + foo.i); } } What is the result?() A、 i = 3B、 Compilation fails.C、 A ClassCastException is thrown at line 6.D、 A ClassCastException is thrown at line 7.
Given the JSP code: and the Classic tag handler code: 5. public int doStartTag() throws JspException { 6. // insert code here 7. // return int 8. } Assume there are no other "foo" attributes in the web application. Which invocation on the pageContextobject,inserted at line 6,assigns "bar" to the variable x?()A、String x = (String) pageContext.getAttribute("foo")B、String x = (String) pageContext.getRequestScope("foo")C、It is NOT possible to access the pageContext object from within doStartTagD、String x = (String) pageContext.getRequest().getAttribute("foo")E、String x = (String) pageContext.getAttribute("foo", PageContext.ANY_SCOPE)
String foo = “blue”; Booleanbar = new Boolean [1]; if (bar[0]) { foo = “green”; } What is the result?() A、 Foo has the value of “”B、 Foo has the value of null.C、 Foo has the value of “blue”D、 Foo has the value of “green”E、 An exception is thrown.F、 The code will not compile.
public class test( public static void main(stringargs){ string foo = args [1]; string foo = args ; string foo = args ; } ) And command line invocation: Java Test red green blue What is the result? () A、 Baz has the value of “”B、 Baz has the value of nullC、 Baz has the value of “red”D、 Baz has the value of “blue”E、 Bax has the value of “green”F、 The program throws an exception.
int index = 1; String [] test = new String[3]; String foo = test[index]; What is the result?() A、 Foo has the value “”B、 Foo has the value nullC、 An exception is thrownD、 The code will not compile