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Java9 Samples

From:

http://hg.openjdk.java.net/kulla/dev/langtools/file/cf2fa1607bd0/repl/samples

In [ ]:
import java.util.*;
int n = 12;
int p = 0, c = 1, a; 
List<Integer> list = new ArrayList<>();

while (n-- > 0) {
    list.add(c);
    a = p + c;
    p = c;
    c = a;
}

System.out.println(list);
In [ ]:
int var1 = 2
int meth2() { 
    return var1+2; 
}

++var1
    
class class3 { 
    int meth4() { 
        return var1 * meth2(); 
    } 
}

System.out.println(new class3().meth4())
In [ ]:
int passCnt
int failCnt
int unexpectedCnt

void check(boolean pass) {
  if (pass) {
    System.out.println("pass");
    ++passCnt;
  } else {
    System.out.println("FAIL");
    ++failCnt;
  }
}

void expectError(boolean huh) {
  System.out.println("Should not be here, should be error");
  ++unexpectedCnt;
}

int m() { return 100; }
int m(int x) { return x; }
int m(int x, int y) { return x * y; }

check(m(5,4) == 20);
check(m(7) == 7);
check(m() == 100);
int m(int x) { return x * 100; }
check(m(3) == 300);
check(m() == 100);
check(m(5,4) == 20);
int m() { return 1234; }
check(m() == 1234);
double m(int x, int y) { return x + y; }
check(m(2,3) == 5.0);
double m(double x, double y) { return y - x; }
check(m(2.0,3.0) == 1.0);
check(m(2,3) == 5.0);
System.out.println((passCnt==10 && failCnt==0 && unexpectedCnt==0)? 
    "Test passes!" : 
    "Test FAILED! Pass: " + passCnt + ", Fail: " + failCnt + ", Unexpected: " + unexpectedCnt)
In [3]:
int passCnt;
int failCnt;
int unexpectedCnt;
/*
void check(boolean pass) {
  if (pass) {
    System.out.println("pass");
    ++passCnt;
  } else {
    System.out.println("FAIL");
    ++failCnt;
  }
}
*/
/*
void expectError(boolean huh) {
  System.out.println("Should not be here, should be error");
  ++unexpectedCnt;
}
*/
int x;
//int mu() { return x * 4; }
//class C {
//  String v() { return "#" + mu(); }
//}
//new C();
//check($1.v().equals("#0"))
    /*
int x = 10
check($1.v().equals("#40"))
C c = new C()
check(c.v().equals("#40"))
int mu() { return x * 3; }
check(c.v().equals("#30"))
class C {
  String v() { return "@@" + mu(); }
}
check($1.v().equals("@@30"))
c = new C()
check(c.v().equals("@@30"))
double x = 2.5
check(x == 2.5)
*/
/*
expectError(mu() == 30)
c = new C()
expectError(c.v().equals("@@30"))
int mu() { return (int) (x * 10); }
check(mu() == 25)
c = new C()
check(c.v().equals("@@25"))
double mu() { return x * 2.0; }
check(mu() == 5.0)
check($1.v().equals("@@5.0"))
c = new C()
check(c.v().equals("@@5.0"))
class C {
  Object v() { return mu(); }
}
//check($1 == null)  //TODO fix update of temp vars
C d = new C()
check(d.v().equals(5.0))

System.out.println((passCnt==13 && failCnt==0 && unexpectedCnt==0)? 
    "Test passes!" : 
    "Test FAILED! Pass: " + passCnt + ", Fail: " + failCnt + ", Unexpected: " + unexpectedCnt)
    */
System.out.println("Ok")

 System.out.println("Ok")
Ok
In [2]:
System.out.println("Ok")

 System.out.println("Ok")
Ok
In [5]:
class Tree {
    Tree left;
    Tree right;
    int value;
    
    Tree(int value) {
        this.value = value;
    }
}

Tree tree = new Tree(10);
tree.left = new Tree(2);

 tree.left = new Tree(2);
|  Expression value is: Tree@33e5ccce
|    assigned to temporary variable $1 of type Tree
Out[5]:
Tree@33e5ccce
In [6]:
tree.left.value

 tree.left.value
|  Expression value is: 2
|    assigned to temporary variable $2 of type int
Out[6]:
2
In [3]:
$2

 $2
|  Variable $2 of type int has value 2
Out[3]:
2
In [1]:
System.out.println(y)

 System.out.println(y)
|  Error:
|  cannot find symbol
|    symbol:   variable y
|  System.out.println(y)
|                     ^
In [2]:
System.out.println(1/0)

 System.out.println(1/0)
|  java.lang.ArithmeticException thrown: / by zero
|        at (#9:1)
In [5]:
System.out.println("ok")

 System.out.println("ok")
ok
In [20]:
%%python

kernel.javawrapper.child.send("varia")
kernel.javawrapper.child.sendcontrol('t')
kernel.javawrapper.child.sendeof()
In [17]:
System.out.println("ok")

 variaSystem.out.println("ok")
|  Error:
|  package variaSystem does not exist
|  variaSystem.out.println("ok")
|  ^-------------^
In [2]:
/help

 /help
Type a Java language expression, statement, or declaration.
Or type one of the following commands:

/l  or /list [all]                -- list the source you have typed
       /seteditor <executable>    -- set the external editor command to use
/e  or /edit <name or id>         -- edit a source entry referenced by name or id
/s  or /save [all|history] <file> -- save the source you have typed
/o  or /open <file>               -- open a file as source input
/v  or /vars                      -- list the declared variables and their values
/m  or /methods                   -- list the declared methods and their signatures
/c  or /classes                   -- list the declared classes
/x  or /exit                      -- exit the REPL
/r  or /reset                     -- reset everything in the REPL
/f  or /feedback <level>          -- feedback information: off, concise, normal, verbose, default, or ?
/p  or /prompt                    -- toggle display of a prompt
/cp or /classpath <path>          -- add a path to the classpath
/h  or /history                   -- history of what you have typed
       /setstart <file>           -- read file and set as the new start-up definitions
       /savestart <file>          -- save the default start-up definitions to the file
/?  or /help                      -- this help message

Supported shortcuts include:
<tab>       -- show possible completions for the current text
Shift-<tab> -- for current method or constructor invocation, show a synopsis of the method/constructor
In [22]:
/help

 /classes
In [8]:
/help

 /help
Type a Java language expression, statement, or declaration.
Or type one of the following commands:

/l  or /list [all]                -- list the source you have typed
       /seteditor <executable>    -- set the external editor command to use
/e  or /edit <name or id>         -- edit a source entry referenced by name or id
/s  or /save [all|history] <file> -- save the source you have typed
/o  or /open <file>               -- open a file as source input
/v  or /vars                      -- list the declared variables and their values
/m  or /methods                   -- list the declared methods and their signatures
/c  or /classes                   -- list the declared classes
/x  or /exit                      -- exit the REPL
/r  or /reset                     -- reset everything in the REPL
/f  or /feedback <level>          -- feedback information: off, concise, normal, verbose, default, or ?
/p  or /prompt                    -- toggle display of a prompt
/cp or /classpath <path>          -- add a path to the classpath
/h  or /history                   -- history of what you have typed
       /setstart <file>           -- read file and set as the new start-up definitions
       /savestart <file>          -- save the default start-up definitions to the file
/?  or /help                      -- this help message

Supported shortcuts include:
<tab>       -- show possible completions for the current text
Shift-<tab> -- for current method or constructor invocation, show a synopsis of the method/constructor
In [ ]:
%%python

kernel.javawrapper.child.read(10)
In [1]:
int variable_name = 1;

 int variable_name = 1;
|  Added variable variable_name of type int with initial value 1
In [3]:
variable_name

 variable_name
|  Variable variable_name of type int has value 1
Out[3]:
1
In [4]:
variable_name

 variable_name
|  Variable variable_name of type int has value 1
Out[4]:
1
In [5]:
variable_name

 variable_name
|  Variable variable_name of type int has value 1
Out[5]:
1
In [9]:
variable_name

 variable_name
|  Variable variable_name of type int has value 1
Out[9]:
1