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【Java4】一些工具

 2 years ago
source link: https://www.guofei.site/2016/06/20/java4.html
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版权声明：本文作者是郭飞。转载随意，但需要标明原文链接，并通知本人
原文链接：https://www.guofei.site/2016/06/20/java4.html

Edit

druid：解析sql

pom.xml

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.2.8</version>
</dependency>

import com.alibaba.druid.DbType;
import com.alibaba.druid.sql.SQLUtils;
import com.alibaba.druid.sql.ast.SQLStatement;
import com.alibaba.druid.sql.ast.expr.SQLAggregateExpr;
import com.alibaba.druid.sql.ast.expr.SQLMethodInvokeExpr;
import com.alibaba.druid.sql.ast.statement.*;
import com.alibaba.druid.sql.visitor.SchemaStatVisitor;
import com.alibaba.druid.stat.TableStat.Column;
import com.alibaba.druid.util.JdbcConstants;
import org.junit.Test;

import java.util.ArrayList;
import java.util.List;


public class ColumnsParser {
    DbType dbType = JdbcConstants.MYSQL; //ODPS


    String sql=
            //"select col1_1 col1_4,sum(col1_2,3) col1_4,col1_2, my_func(col1_3,1) col9 " +
            //"from table1 " +
            //"where col2=3 and col2_2 in (select col9 from table2) " +
            //"group by col3 " +
            //"order by col4";

     "select col1 as col1_1,col2 col2_2,greatest(col1_3,col1_4,5),col1_3,sum(col1_5) col3 from table1 t1 where col4=1 group by col5 order by col6";

    //sql ="select col1 /*\n" +
    //        "    comments1*/, col2 /**/\n" +
    //        "    ,col3/* comments2*/ from table1\n" +
    //        "    where col4 in ('a','b','c')-- and col2=1" +
    //        "and col3=5";

    //sql = "INSERT INTO students (name, sex, age) VALUES (\"王刚\", \"男\", 21);";

    //sql="select col1 as col1_1,col2 col2_2,greatest(col3_3,1,5) col3 from table1 t1";


    List<SQLStatement> stmtList = SQLUtils.parseStatements(sql, dbType);

    @Test
    public void tst1() {
        System.out.println(sql);
        SchemaStatVisitor statVisitor = SQLUtils.createSchemaStatVisitor(dbType);
        SQLStatement stmt = stmtList.get(0);
        stmt.accept(statVisitor);


        System.out.println(statVisitor.getTables().toString());
        //用了哪些表{table1=Select}, {table2=Insert}
        System.out.println(statVisitor.getTables().keySet());
        //[table1]


        System.out.println(statVisitor.getColumns().toString());
        //用了哪些字段[table1.col1, table1.col2, table1.col3_3]

        //如何使用的函数
        System.out.println(statVisitor.getFunctions());
        //[greatest(col1_3, col1_4, 5)]
        SQLMethodInvokeExpr sqlMethodInvokeExpr = statVisitor.getFunctions().get(0);
        System.out.println(sqlMethodInvokeExpr.getArguments()); // 函数的入参 [col1_3, 1]
        System.out.println(sqlMethodInvokeExpr.getMethodName()); // 函数本身  my_func


        //聚合函数
        System.out.println(statVisitor.getAggregateFunctions().toString());
        //[sum(col1_2, 3)]
        SQLAggregateExpr sqlAggregateExpr = statVisitor.getAggregateFunctions().get(0);
        System.out.println(sqlAggregateExpr.getMethodName()); // 方法，例如sum
        System.out.println(sqlAggregateExpr.getArguments()); // 入参


        //where 条件
        System.out.println(statVisitor.getConditions().toString());
        //[table1.col2 = 3, table1.col2_2 IN]

        //groupby哪些字段
        System.out.println(statVisitor.getGroupByColumns().toString());
        //orderby哪些字段
        System.out.println(statVisitor.getOrderByColumns().toString());


        System.out.println(statVisitor.getParameters());// 不知道啥
        System.out.println(statVisitor.getRelationships());//不知道啥


        System.out.println("找到select");


        for (Column col : statVisitor.getColumns()) {
            System.out.println("" + col + col.isSelect());
            System.out.println("" + col + col.isGroupBy());
            System.out.println("" + col + col.isHaving());
            System.out.println("" + col + col.isJoin());
            System.out.println("" + col + col.isWhere());
            System.out.println("unique: " + col + col.isUnique()); // 不知道是啥
            System.out.println("update: " + col + col.isUpdate()); // 不知道是啥


            System.out.println("getAttributes" + col + col.getFullName()); // table.col
            System.out.println("getAttributes" + col + col.getName()); // col
            System.out.println("getAttributes" + col + col.getTable()); // table
            System.out.println("getAttributes" + col + col.getAttributes()); // 不知道啥，空
            System.out.println("getAttributes" + col + col.getDataType()); // null
        }

    }


    @Test
    public void tst2() {
        String sql_text = "select col1 as col1_1,col2 col2_2,greatest(col1_3,col1_4,5),col1_3,sum(col1_5) col3 from table1 t1 where col4=1 group by col5 order by col6";

        List<SQLStatement> statements = SQLUtils.parseStatements(sql_text, dbType);
        SQLStatement statement = statements.get(0);

        //判断它是什么语句
        System.out.println(statement instanceof SQLSelectStatement);
        System.out.println(statement instanceof SQLUpdateStatement);
        System.out.println(statement instanceof SQLDeleteStatement);
        System.out.println(statement instanceof SQLInsertStatement);


        //    取出select
        SQLSelectStatement selectStatement = (SQLSelectStatement) statement;
        SQLSelectQueryBlock queryBlock = selectStatement.getSelect().getFirstQueryBlock();
        SQLSelectQuery sqlSelectQuery = selectStatement.getSelect().getQuery();

        //成功取出 select
        System.out.println(queryBlock.getSelectList());
        System.out.println(queryBlock.getFrom());
        System.out.println(queryBlock.getInto());
        System.out.println(queryBlock.getWhere());
        System.out.println(queryBlock.getGroupBy());
        System.out.println(queryBlock.getOrderBy());
        System.out.println(queryBlock.getLimit());


        System.out.println("看看select:");
        //    看看select
        for (SQLSelectItem i : queryBlock.getSelectList()) {
            System.out.println(i);
        }
    }

    @Test
    public void tst3() {
        /*目标
        sql_type: select/insert/update/delete
        table_name
        column_name
        type：select，groupBy，orderBy
        function 完整。
        function 仅函数名。如果没有函数，则显示 direct
         */
    }

}

读写文件

public ArrayList<String> readFile(String file) throws IOException {
    ArrayList<String> context = new ArrayList<String>();
    BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
    String text;
    while ((text = bufferedReader.readLine()) != null) {
        context.add(text);
    }
    return context;
}

public void writeFile(String file, ArrayList<String> data) throws IOException {
    BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(file));
    for (String line : data) {
        bufferedWriter.write(line);
    }
    bufferedWriter.close();
}

FileUtils

package com.guofei9987.tst_read.utils;


import com.opencsv.CSVReader;
import com.opencsv.CSVReaderBuilder;
import org.springframework.util.StringUtils;

import java.io.*;
import java.nio.charset.Charset;
import java.nio.file.Files;
import java.util.*;


/**
 * 用法：
 * List<String> context = FileUtils.getContentListByLine("ill/illname_model_word.txt");
 **/


public class FileUtils {

    public static Charset charset = Charset.defaultCharset(); // 这里用来改编码格式

    public static byte[] getFileBytes(String fileName) {
        try {
            File file = new File(Objects.requireNonNull(FileUtils.class.getClassLoader().getResource(fileName)).toURI());
            if (file.isFile()) {
                return Files.readAllBytes(file.toPath());
            }
        } catch (Exception e) {
            System.out.println("warn: " + e.getMessage() + e);
        }
        return null;
    }

    public static String getContentStringByLine(String filePath) {
        return String.join("\n", getContentListByLine(filePath));
    }


    public static List<String> getContentListByLine(String filePath) {
        List<String> res = new ArrayList<>();
        fillCollectionByLine(res, filePath);
        return res;
    }

    public static Set<String> getContentSetByLine(String filePath) {
        Set<String> res = new HashSet<>();
        fillCollectionByLine(res, filePath);
        return res;
    }

    private static void fillCollectionByLine(Collection<String> collection, String filePath) {
        try {
            InputStream stream = FileUtils.class.getClassLoader().getResourceAsStream(filePath);
            assert stream != null;
            BufferedReader breader = new BufferedReader(new InputStreamReader(stream, charset));
            String str;
            while ((str = breader.readLine()) != null) {
                if (!StringUtils.hasText(str)) {
                    continue;
                }
                collection.add(str);
            }
            breader.close();
            stream.close();
        } catch (IOException e) {
            System.out.println("warn: " + e.getMessage() + e);
        }
    }

    public static ArrayList<ArrayList<String>> getContentCSVByLine(String filePath) {
        ArrayList<ArrayList<String>> res = new ArrayList<ArrayList<String>>();
        InputStream stream = FileUtils.class.getClassLoader().getResourceAsStream(filePath);
        BufferedReader bufferedReader;
        try {
            assert stream != null;
            bufferedReader = new BufferedReader(new InputStreamReader(stream, charset));
            CSVReader csvReader = new CSVReaderBuilder(bufferedReader).build();

            for (String[] strings : csvReader) {

                res.add(new ArrayList<String>(Arrays.asList(strings)));
                //Arrays.stream(strings).filter(StringUtils::hasText).forEach(collection::add);
            }
        } catch (Exception e) {
            System.out.println("warn: " + e.getMessage() + e);

        }
        return res;
    }




    public static Map<String, byte[]> getPathBytes(String dirName) {
        // 获取一个目录下所有文件内容( byte array )
        Map<String, byte[]> res = new HashMap<>();
        try {
            File dir = new File(Objects.requireNonNull(FileUtils.class.getClassLoader().getResource(dirName)).toURI());
            for (File file : Objects.requireNonNull(dir.listFiles())) {
                if (file.isFile()) {
                    byte[] bytes = Files.readAllBytes(file.toPath());
                    res.put(file.getName(), bytes);
                }
            }
        } catch (Exception e) {
            System.out.println("warn: " + e.getMessage() + e);
        }
        return res;
    }

    public static Map<String, String> getPathString(String dirName) {
        Map<String, String> res = new HashMap<>();
        Map<String, byte[]> res1 = getPathBytes(dirName);
        for (Map.Entry<String, byte[]> entry : res1.entrySet()) {
            res.put(entry.getKey(), new String(entry.getValue()));
        }
        return res;
    }

}

jieba

<dependency>
    <groupId>com.huaban</groupId>
    <artifactId>jieba-analysis</artifactId>
    <version>1.0.2</version>
</dependency>

public class AbstractSegmenter extends AbstractPmmlPredictor {
    static {
        //加载自定义的词典进词库
        Path path = Paths.get(new File(Hospital.class.getClassLoader().getResource("keywords/keyword_hospital_ends1.txt").getPath()).getAbsolutePath());
        WordDictionary.getInstance().loadUserDict(path);
    }

    public JiebaSegmenter segmenter = new JiebaSegmenter();

    @Test
    public void tstSegment() {
        String text = "商品和服务";
        List<SegToken> cut = segmenter.process(text, JiebaSegmenter.SegMode.SEARCH);
        System.out.println(cut);
    }
}

杂七杂八

字符串

写入文件

String path="/Users/guofei/git/results.txt";
BufferedWriter bw = new BufferedWriter(new FileWriter(path));
String ss = "测试数据";
bw.write(ss);
bw.newLine();  //换行用

//关闭流
bw.close();
System.out.println("写入成功");

正则

import java.util.regex.Matcher;
import java.util.regex.Pattern;


// 找到所有匹配的子字符串
String regStr = "\\d+";
Pattern p = Pattern.compile(regStr);
String data = "111a222b333";
Matcher matcher = p.matcher("111a222b333");
while (matcher.find()) {
    String s = matcher.group().trim();
    if (StringUtils.hasText(s)) {
        System.out.println(s);
    }
}


boolean isMatch = Pattern.matches(pattern, content);

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