49 lines
1.1 KiB
Java
49 lines
1.1 KiB
Java
// functional/LambdaExpressions.java
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// (c)2021 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://OnJava8.com for more book information.
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interface Description {
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String brief();
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}
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interface Body {
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String detailed(String head);
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}
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interface Multi {
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String twoArg(String head, Double d);
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}
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public class LambdaExpressions {
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static Body bod = h -> h + " No Parens!"; // [1]
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static Body bod2 = (h) -> h + " More details"; // [2]
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static Description desc = () -> "Short info"; // [3]
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static Multi mult = (h, n) -> h + n; // [4]
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static Description moreLines = () -> { // [5]
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System.out.println("moreLines()");
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return "from moreLines()";
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};
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public static void main(String[] args) {
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System.out.println(bod.detailed("Oh!"));
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System.out.println(bod2.detailed("Hi!"));
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System.out.println(desc.brief());
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System.out.println(mult.twoArg("Pi! ", 3.14159));
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System.out.println(moreLines.brief());
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}
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}
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/* Output:
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Oh! No Parens!
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Hi! More details
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Short info
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Pi! 3.14159
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moreLines()
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from moreLines()
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*/
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