blok类型数据查询

gjjs-bd-mybatis-support/src/main/java/com/brilliance/mda/support/mybatis/StringBlobTypeHandler.java

+package com.brilliance.mda.support.mybatis;
+
+import org.apache.ibatis.type.BaseTypeHandler;
+import org.apache.ibatis.type.JdbcType;
+import org.apache.ibatis.type.MappedJdbcTypes;
+import org.apache.ibatis.type.MappedTypes;
+import org.springframework.stereotype.Component;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.sql.*;
+
+/**
+ * @Description
+ * @Author s_guodong
+ * @Date 2023/8/24
+ */
+@MappedJdbcTypes(JdbcType.BLOB)
+@MappedTypes(String.class)
+@Component
+public class StringBlobTypeHandler extends BaseTypeHandler<String> {
+    @Override
+    public void setNonNullParameter(PreparedStatement ps, int i, String parameter, JdbcType jdbcType) throws SQLException {
+        // 声明一个输入流对象
+        ByteArrayInputStream bis = null;
+        String param = null;
+        if (parameter != null) {
+            //这里强转是因为知道了是String类型,可以看具体情况而定
+            param = parameter;
+        }
+        try {
+            // 把字符串转为字节流
+            bis = new ByteArrayInputStream(param.getBytes("utf-8"));
+        } catch (Exception e) {
+            throw new RuntimeException("Blob Encoding Error!");
+        } finally {
+            if (bis != null) {
+                try {
+                    bis.close();
+                } catch (IOException e) {
+                    throw new RuntimeException("Blob Encoding Error!");
+                }
+            }
+        }
+        ps.setBinaryStream(i, bis, param.length());
+    }
+
+    @Override
+    public String getNullableResult(ResultSet rs, String columnName) throws SQLException {
+        Blob blob = rs.getBlob(columnName);
+        String returnValue = null;
+        if (null != blob) {
+            returnValue = new String(blob.getBytes(1L, (int) blob.length()));
+        }
+        return returnValue;
+    }
+
+    @Override
+    public String getNullableResult(ResultSet rs, int columnIndex) throws SQLException {
+        Blob blob = rs.getBlob(columnIndex);
+        String returnValue = null;
+        if (null != blob) {
+            returnValue = new String(blob.getBytes(1L, (int) blob.length()));
+        }
+        return returnValue;
+    }
+
+    @Override
+    public String getNullableResult(CallableStatement cs, int columnIndex) throws SQLException {
+        Blob blob = cs.getBlob(columnIndex);
+        String returnValue = null;
+        if (null != blob) {
+            returnValue = new String(blob.getBytes(1L, (int) blob.length()));
+        }
+        return returnValue;
+    }
+
+
+}