应用Java泛型和反射导出CSV文件

项目中有需求要把数据导出为CSV文件,因为不同的类有不同的属性,为了代码简单,应用Java的泛型和反射,写了一个函数,完成导出功能。

public <T> void saveFile(List<T> list, String outFile) throws IOException {

        if (list == null || list.isEmpty()) {

            return;

        }

        if (StringUtils.isEmpty(outFile)) {

            throw new IllegalArgumentException("outfile is null");

        }

        boolean isFirst = true;

        BufferedWriter out = null;

        try {

            out = new BufferedWriter(new FileWriter(outFile));

            for (T t : list) {

                StringBuilder sb1 = new StringBuilder();

                StringBuilder sb2 = new StringBuilder();

                Class clazz = (Class) t.getClass();

                Field[] fs = clazz.getDeclaredFields();

                for (int i = 0; i < fs.length; i++) {

                    Field f = fs[i];

                    f.setAccessible(true);

                    try {

                        if (isFirst) {

                            sb1.append(f.getName());

                            sb1.append(",");

                        }

                        Object val = f.get(t);

                        if (val == null) {

                            sb2.append("");

                        } else {

                            sb2.append(val.toString());

                        }

                        sb2.append(",");

                    } catch (IllegalArgumentException | IllegalAccessException e) {

                        e.printStackTrace();

                    }

                }

                if (isFirst) {

                    out.write(sb1.toString());

                    isFirst = false;

                    out.newLine();

                }

                out.write(sb2.toString());

                out.newLine();

            }

        } catch (IOException e1) {

            throw e1;

        } finally {

            try {

                if (out != null) {

                    out.close();

                }

            } catch (IOException e2) {

                throw e2;

            }

        }

    }

 

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