Don't substring twice. Use the found index twice instead: int idx = example.lastIndexOf("id\":\""); example = example.substring(idx + 5, ... ... <看更多>

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package codgen.row_functions;. import java.util.ArrayList;. public class Substr implements RowFunction {. private String param1, param2;. ... <看更多>

A practical reason is that it makes things easier in some common situations: If you want the operation to include everything until the end ... ... <看更多>