Nullability fine-tuning based on IntelliJ IDEA 2018.3 inspection

Issue: SPR-15540

(cherry picked from commit bf272b0b21)

spring-jdbc/src/main/java/org/springframework/jdbc/core/namedparam/NamedParameterUtils.java

@@ -111,25 +111,25 @@ public abstract class NamedParameterUtils {
 			char c = statement[i];
 			if (c == ':' || c == '&') {
 				int j = i + 1;
-				if (j < statement.length && statement[j] == ':' && c == ':') {
+				if (c == ':' && j < statement.length && statement[j] == ':') {
 					// Postgres-style "::" casting operator should be skipped
 					i = i + 2;
 					continue;
 				}
 				String parameter = null;
-				if (j < statement.length && c == ':' && statement[j] == '{') {
+				if (c == ':' && j < statement.length && statement[j] == '{') {
 					// :{x} style parameter
-					while (j < statement.length && statement[j] != '}') {
+					while (statement[j] != '}') {
 						j++;
+						if (j >= statement.length) {
+							throw new InvalidDataAccessApiUsageException("Non-terminated named parameter declaration " +
+									"at position " + i + " in statement: " + sql);
+						}
 						if (statement[j] == ':' || statement[j] == '{') {
 							throw new InvalidDataAccessApiUsageException("Parameter name contains invalid character '" +
 									statement[j] + "' at position " + i + " in statement: " + sql);
 						}
 					}
-					if (j >= statement.length) {
-						throw new InvalidDataAccessApiUsageException(
-								"Non-terminated named parameter declaration at position " + i + " in statement: " + sql);
-					}
 					if (j - i > 2) {
 						parameter = sql.substring(i + 2, j);
 						namedParameterCount = addNewNamedParameter(namedParameters, namedParameterCount, parameter);
@@ -202,7 +202,7 @@ public abstract class NamedParameterUtils {
 	}
 
 	/**
-	 * Skip over comments and quoted names present in an SQL statement
+	 * Skip over comments and quoted names present in an SQL statement.
 	 * @param statement character array containing SQL statement
 	 * @param position current position of statement
 	 * @return next position to process after any comments or quotes are skipped

spring-jdbc/src/main/java/org/springframework/jdbc/object/RdbmsOperation.java

@@ -211,7 +211,7 @@ public abstract class RdbmsOperation implements InitializingBean {
 	 * Set the column names of the auto-generated keys.
 	 * @see java.sql.Connection#prepareStatement(String, String[])
 	 */
-	public void setGeneratedKeysColumnNames(String... names) {
+	public void setGeneratedKeysColumnNames(@Nullable String... names) {
 		if (isCompiled()) {
 			throw new InvalidDataAccessApiUsageException(
 					"The column names for the generated keys must be set before the operation is compiled");
@@ -230,7 +230,7 @@ public abstract class RdbmsOperation implements InitializingBean {
 	/**
 	 * Set the SQL executed by this operation.
 	 */
-	public void setSql(String sql) {
+	public void setSql(@Nullable String sql) {
 		this.sql = sql;
 	}
 
@@ -297,7 +297,7 @@ public abstract class RdbmsOperation implements InitializingBean {
 	 * Add one or more declared parameters. Used for configuring this operation
 	 * when used in a bean factory.  Each parameter will specify SQL type and (optionally)
 	 * the parameter's name.
-	 * @param parameters Array containing the declared {@link SqlParameter} objects
+	 * @param parameters an array containing the declared {@link SqlParameter} objects
 	 * @see #declaredParameters
 	 */
 	public void setParameters(SqlParameter... parameters) {

spring-jdbc/src/main/java/org/springframework/jdbc/object/SqlCall.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -40,13 +40,6 @@ import org.springframework.util.Assert;
  */
 public abstract class SqlCall extends RdbmsOperation {
 
-	/**
-	 * Object enabling us to create CallableStatementCreators
-	 * efficiently, based on this class's declared parameters.
-	 */
-	@Nullable
-	private CallableStatementCreatorFactory callableStatementFactory;
-
 	/**
 	 * Flag used to indicate that this call is for a function and to
 	 * use the {? = call get_invoice_count(?)} syntax.
@@ -54,20 +47,26 @@ public abstract class SqlCall extends RdbmsOperation {
 	private boolean function = false;
 
 	/**
-	 * Flag used to indicate that the sql for this call should be used exactly as it is
-	 * defined.  No need to add the escape syntax and parameter place holders.
+	 * Flag used to indicate that the sql for this call should be used exactly as
+	 * it is defined. No need to add the escape syntax and parameter place holders.
 	 */
 	private boolean sqlReadyForUse = false;
 
 	/**
 	 * Call string as defined in java.sql.CallableStatement.
-	 * String of form {call add_invoice(?, ?, ?)}
-	 * or {? = call get_invoice_count(?)} if isFunction is set to true
-	 * Updated after each parameter is added.
+	 * String of form {call add_invoice(?, ?, ?)} or {? = call get_invoice_count(?)}
+	 * if isFunction is set to true. Updated after each parameter is added.
 	 */
 	@Nullable
 	private String callString;
 
+	/**
+	 * Object enabling us to create CallableStatementCreators
+	 * efficiently, based on this class's declared parameters.
+	 */
+	@Nullable
+	private CallableStatementCreatorFactory callableStatementFactory;
+
 
 	/**
 	 * Constructor to allow use as a JavaBean.
@@ -83,8 +82,8 @@ public abstract class SqlCall extends RdbmsOperation {
 	/**
 	 * Create a new SqlCall object with SQL, but without parameters.
 	 * Must add parameters or settle with none.
-	 * @param ds DataSource to obtain connections from
-	 * @param sql SQL to execute
+	 * @param ds the DataSource to obtain connections from
+	 * @param sql the SQL to execute
 	 */
 	public SqlCall(DataSource ds, String sql) {
 		setDataSource(ds);
@@ -103,7 +102,7 @@ public abstract class SqlCall extends RdbmsOperation {
 	 * Return whether this call is for a function.
 	 */
 	public boolean isFunction() {
-		return function;
+		return this.function;
 	}
 
 	/**
@@ -117,7 +116,7 @@ public abstract class SqlCall extends RdbmsOperation {
 	 * Return whether the SQL can be used as is.
 	 */
 	public boolean isSqlReadyForUse() {
-		return sqlReadyForUse;
+		return this.sqlReadyForUse;
 	}
 
 
@@ -129,30 +128,32 @@ public abstract class SqlCall extends RdbmsOperation {
 	@Override
 	protected final void compileInternal() {
 		if (isSqlReadyForUse()) {
-			this.callString = getSql();
+			this.callString = resolveSql();
 		}
 		else {
+			StringBuilder callString = new StringBuilder(32);
 			List<SqlParameter> parameters = getDeclaredParameters();
 			int parameterCount = 0;
 			if (isFunction()) {
-				this.callString = "{? = call " + getSql() + "(";
+				callString.append("{? = call ").append(resolveSql()).append('(');
 				parameterCount = -1;
 			}
 			else {
-				this.callString = "{call " + getSql() + "(";
+				callString.append("{call ").append(resolveSql()).append('(');
 			}
 			for (SqlParameter parameter : parameters) {
-				if (!(parameter.isResultsParameter())) {
+				if (!parameter.isResultsParameter()) {
 					if (parameterCount > 0) {
-						this.callString += ", ";
+						callString.append(", ");
 					}
 					if (parameterCount >= 0) {
-						this.callString += "?";
+						callString.append('?');
 					}
 					parameterCount++;
 				}
 			}
-			this.callString += ")}";
+			callString.append(")}");
+			this.callString = callString.toString();
 		}
 		if (logger.isDebugEnabled()) {
 			logger.debug("Compiled stored procedure. Call string is [" + this.callString + "]");