Java Requires Chilkat v11.1.0+

Unicode Escape

Demonstrates options for unicode escaping non-us-ascii chars and emojis. Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Crypt2;
import com.chilkatsoft.chilkat2.StringBuilder;

public class ChilkatExample {

    public static void main(String[] args) {
        StringBuilder sb = new StringBuilder();
        try {
            sb.loadFile("qa_data/txt/utf16_emojis_accented_jap.txt", "utf-16");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        String original = sb.getAsString();

        // The above file contains the following text, which includes some emoji's,
        // Japanese chars, and accented chars.

        // 🧠
        // 🔐
        // ✅
        // ⚠️
        // ❌
        // ✓
        // 中
        // é xyz à
        // abc 私 は ん ghi

        Crypt2 crypt = new Crypt2();

        // Charset is not used for unicode escaping.  Set it to "utf-8", but it means nothing.
        String charsetNotUsed = "utf-8";

        // Indicate the desired format/style of Unicode escaping.
        // Choose JSON-style (JavaScript-style) Unicode escape sequences by using "unicodeescape"
        String encoding = "unicodeescape";

        String escaped = crypt.encodeString(original, charsetNotUsed, encoding);
        System.out.println(escaped);

        // Output:
        // \ud83e\udde0
        // \ud83d\udd10
        // \u2705
        // \u26a0\ufe0f
        // \u274c
        // \u2713
        // \u4e2d
        // \u00e9 xyz \u00e0
        // abc \u79c1 \u306f \u3093 ghi

        // Revert back to the unescaped chars:
        String unescaped = crypt.decodeString(escaped, charsetNotUsed, encoding);
        System.out.println(unescaped);

        // -----------------------------------------------------------------------------------------
        // Do the same, but use uppercase letters (A-F) in the hex values.
        encoding = "unicodeescape-upper";
        escaped = crypt.encodeString(original, charsetNotUsed, encoding);
        System.out.println(escaped);

        // Output:
        // \uD83E\uDDE0
        // \uD83D\uDD10
        // \u2705
        // \u26A0\uFE0F
        // \u274C
        // \u2713
        // \u4E2D
        // \u00E9 xyz \u00E0
        // abc \u79C1 \u306F \u3093 ghi

        // Revert back to the unescaped chars:
        unescaped = crypt.decodeString(escaped, charsetNotUsed, encoding);
        System.out.println(unescaped);

        // -----------------------------------------------------------------------------------------
        //  ECMAScript (JavaScript) “code point escape” syntax

        encoding = "unicodeescape-curly";
        escaped = crypt.encodeString(original, charsetNotUsed, encoding);
        System.out.println(escaped);

        // Output:
        // \\u{d83e}\\u{dde0}
        // \\u{d83d}\\u{dd10}
        // \\u{2705}
        // \\u{26a0}\\u{fe0f}
        // \\u{274c}
        // \\u{2713}
        // \\u{4e2d}
        // \\u{00e9} xyz \\u{00e0}
        // abc \\u{79c1} \\u{306f} \\u{3093} ghi

        // Revert back to the unescaped chars:
        unescaped = crypt.decodeString(escaped, charsetNotUsed, encoding);
        System.out.println(unescaped);

        // -----------------------------------------------------------------------------------------
        // Do the same, but use uppercase letters (A-F) in the hex values.
        encoding = "unicodeescape-curly-upper";
        escaped = crypt.encodeString(original, charsetNotUsed, encoding);
        System.out.println(escaped);

        // Output:
        // \\u{D83E}\\u{DDE0}
        // \\u{D83D}\\u{DD10}
        // \\u{2705}
        // \\u{26A0}\\u{FE0F}
        // \\u{274C}
        // \\u{2713}
        // \\u{4E2D}
        // \\u{00E9} xyz \\u{00E0}
        // abc \\u{79C1} \\u{306F} \\u{3093} ghi

        // Revert back to the unescaped chars:
        unescaped = crypt.decodeString(escaped, charsetNotUsed, encoding);
        System.out.println(unescaped);

        // -----------------------------------------------------------------------------------------
        // Unicode code point notation or U+ notation

        encoding = "unicodeescape-plus";
        escaped = crypt.encodeString(original, charsetNotUsed, encoding);
        System.out.println(escaped);

        // Output:
        // u+1f9e0
        // u+1f510
        // u+2705
        // u+26a0u+fe0f
        // u+274c
        // u+2713
        // u+4e2d
        // u+00e9 xyz u+00e0
        // abc u+79c1 u+306f u+3093 ghi

        // Chilkat cannot unescape the Unicode code point notation or U+ notation.
        // For this style, Chilkat only goes in one direction, which is to escape.

        // To emit uppercase hex, specify unicodeescape-plus-upper
        encoding = "unicodeescape-plus-upper";
        // ...
        // ...

        // -----------------------------------------------------------------------------------------
        // HTML hexadecimal character reference

        encoding = "unicodeescape-htmlhex";
        escaped = crypt.encodeString(original, charsetNotUsed, encoding);
        System.out.println(escaped);

        // Output:
        // 🧠
        // 🔐
        // ✅
        // ⚠️
        // ❌
        // ✓
        // 中
        // é xyz à
        // abc 私 は ん ghi

        // Revert back to the unescaped chars:
        unescaped = crypt.decodeString(escaped, charsetNotUsed, encoding);
        System.out.println(unescaped);

        // -----------------------------------------------------------------------------------------
        // HTML decimal character reference

        encoding = "unicodeescape-htmldec";
        escaped = crypt.encodeString(original, charsetNotUsed, encoding);
        System.out.println(escaped);

        // Output:
        // 🧠
        // 🔐
        // ✅
        // ⚠️
        // ❌
        // ✓
        // 中
        // é xyz à
        // abc 私 は ん ghi

        // Revert back to the unescaped chars:
        unescaped = crypt.decodeString(escaped, charsetNotUsed, encoding);
        System.out.println(unescaped);

        // -----------------------------------------------------------------------------------------
        // Hex in Angle Brackets

        encoding = "unicodeescape-angle";
        escaped = crypt.encodeString(original, charsetNotUsed, encoding);
        System.out.println(escaped);

        // Output:
        // <1f9e0>
        // <1f510>
        // <2705>
        // <26a0><fe0f>
        // <274c>
        // <2713>
        // <4e2d>
        // <e9> xyz <e0>
        // abc <79c1> <306f> <3093> ghi

        // Chilkat cannot unescape the angle bracket notation.
        // For this style, Chilkat only goes in one direction, which is to escape.
    }
}